JP5355091B2 - System and method for correcting pressure fluctuations using a motor - Google Patents

Abstract

Systems and methods for compensating for pressure increase which may occur in various enclosed spaces of a pumping apparatus are disclosed. Embodiments of the present invention may compensate for pressure increases in chambers of a pumping apparatus by moving a pumping means of the pumping apparatus to adjust the volume of the chamber to compensate for a pressure increase in the chamber. More specifically, in one embodiment, to account for unwanted pressure increases to the fluid in a dispense chamber the dispense motor may be reversed to back out piston to compensate for any pressure increase in the dispense chamber.

Description

(Related application)
This application was filed on December 2, 2005 by the inventors George Gonnella, James Cedrone, Raymond Zagars and Robert McLoughlin, whose name is “System and Method for Correcting United States”. The priority of patent application 60 / 741,681 is claimed, the entire contents of which are expressly incorporated herein by reference for all purposes. This application was filed on February 4, 2005 as Raymond A.D. This is a continuation-in-part of US patent application Ser. No. 11 / 051,576 filed by Zagars et al., Whose name is “Pump Controller for Precision Pumping Apparatus”, the latter of which was invented on November 23, 1999. Filed by Zagars et al., A divisional application of US Patent Application No. 09 / 447,604, entitled “Pump Controller for Precision Pumping Apparatus”, which was filed on November 23, 1998. Claiming the benefit of priority of Patent Act Section 119 of provisional patent application 60 / 109,568, the entire contents of which are expressly incorporated herein by reference for all purposes.

(Technical field of the invention)
The present invention relates generally to fluid pumps. More specifically, embodiments of the present invention relate to multi-stage pumps. More specifically, embodiments of the present invention relate to the correction of pressure fluctuations caused by operation of components within pumps used in semiconductor manufacturing.

  There are a number of applications where precise control of fluid volume and / or speed is required when fluid is dispensed by the pumping device. In semiconductor processing, it is important to control the amount and rate of photochemicals such as, for example, photoresist chemicals when they are applied to a semiconductor wafer. Coatings applied to semiconductor wafers during processing generally require flatness across the surface of the wafer, measured in angstroms. The rate at which processing chemicals are applied to the wafer must be controlled so that the processing liquid is applied uniformly.

  Many photochemicals used in the semiconductor industry today are very expensive and often cost $ 1000 per liter. Therefore, it is preferred that a minimal but sufficient amount of chemical is used so that the chemical is not degraded by the pumping device. Current multi-stage pumps can cause rapid pressure spikes in the liquid. For example, negative pressure spikes can promote gasification and bubble formation in chemicals and can cause defects during wafer coating. Similarly, positive pressure spikes can cause premature polymer cross-linking, which can also be a coating defect.

  Such pressure spikes and subsequent pressure drops may degrade the fluid as described above (ie, may adversely change the physical properties of the fluid). In addition, pressure spikes can lead to an increase in fluid pressure, causing the dispensing pump to dispense more fluid than intended, or cause fluid to be dispensed in a form that has unsuitable dynamic characteristics.

  More specifically, when a mixing space is created in the pump device by closing the valve, closing the valve may increase the pressure in the mixing space. This pressure increase can be particularly detrimental when it occurs in a dispensing chamber containing fluid waiting to be dispensed. Therefore, a method for compensating for the pressure increase due to the movement of the valve in the pump device is desired.

  A system and method that compensates for pressure increases (or drops) that may occur in various enclosed spaces of a pump device. Embodiments of the present invention operate by increasing the pressure in the chamber of the pump device by operating the pump means of the pump device to adjust the chamber volume to compensate for the pressure increase (or decrease) in the chamber. Can be compensated. More specifically, in one embodiment, in order to compensate for unwanted pressure rises on the fluid in the distribution chamber, the dispensing motor is counter-rotated to return the piston to compensate for any pressure rise in the distribution chamber. It is possible.

  Embodiments of the present invention provide systems and methods for correcting pressure fluctuations that substantially eliminate or reduce the disadvantages of previously developed pump systems and methods. More specifically, embodiments of the present invention provide systems for correcting pressure fluctuations in a chamber caused by the operation of various mechanisms or components incorporated in a multi-stage pump or device used with a multi-stage pump, and Provide a method.

  One embodiment of the present invention can compensate for pressure changes in the distribution chamber caused by closing the purge valve before the start of the distribution segment. This correction is accomplished by reversing the dispensing motor so that the volume in the dispensing chamber increases by approximately the purge valve hold-up capacity.

  Another embodiment of the present invention is to reverse the dispensing motor by rotating it further to a further distance and by rotating the dispensing motor forward by an amount equal to this further distance before the dispensing segment. Make the last movement forward.

  Embodiments of the present invention can provide the advantage that the desired reference pressure for dispensing can be achieved in the dispensing chamber prior to the dispensing segment.

  Other embodiments of the present invention can provide the ability to compensate for differences in devices used with multi-stage pumps, such as head pressure differences between systems.

  Certain embodiments of the present invention provide benefits by compensating for any backlash that may occur in the drive assembly of the dispensing motor so that the impact on backlash dispensing is negligible.

  These and other aspects of the invention will be better appreciated and understood by reference to the following description and the accompanying drawings. While various embodiments of the invention and numerous specific details thereof have been shown, the following description is intended to be illustrative and not limiting. Numerous substitutions, improvements, additions, or rearrangements can be made within the scope of the present invention, and the present invention encompasses all such substitutions, improvements, additions, or rearrangements.

  The invention and its advantages are more fully understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals indicate like features.

  Preferred embodiments of the invention are illustrated in the drawings, wherein like reference numerals are used for like or corresponding elements of the various drawings.

  Embodiments of the present invention relate to a pump system that uses a pump to accurately dispense fluid, which can be a single stage pump or a multi-stage ("multi-stage") pump. More specifically, embodiments of the present invention can compensate for pressure increases (or drops) that can occur in various enclosed spaces of the pump device. Embodiments of the present invention can compensate for pressure fluctuations in the chamber of the pump apparatus by operating the pump means of the pump apparatus to adjust the volume of the chamber to compensate for pressure fluctuations. More specifically, in one embodiment, in order to compensate for the unwanted pressure rise on the fluid in the distribution chamber, the dispensing motor is rotated back to return the piston to compensate for any pressure increase in the distribution chamber. It is possible. An embodiment of such a pump system is described in US Provisional Patent Application No. 60 / 742,435 by inventors James Cedrone, George Gonella, and Iraj Gashgaee, entitled “System and Method for Multi-pump with Reduced Feduced Feduced Fed”. (Filed Dec. 5, 2005), which is incorporated herein by reference in its entirety.

  FIG. 1 is a diagram illustrating one embodiment of the pump system 10. The pump system 10 can include a fluid source 15, a pump controller 20, and a multi-stage pump 100 that act together to distribute fluid onto the wafer 25. The operation of the multi-stage pump 100 can be controlled by the pump controller 20, which is mounted on the multi-stage pump 100 or 1 for communicating communication control signals, data, or other information. It can be connected to the multistage pump 100 via one or more communication links. In addition, the function of the pump controller 20 can be distributed between the on-board controller and another controller. The pump controller 20 includes a set of control instructions 30 that control the operation of the multi-stage pump 100 (eg, RAM, ROM, flash memory, optical disk, magnetic drive, or other computer readable medium). Can be included. A processor 35 (eg, a CPU, ASIC, RISC, DSP, or other processor) can execute the instructions. An example of a processor is a TMS320F2812PGFA 16-bit DSP from Texas Instruments (a company based in Dallas, Texas). In the embodiment of FIG. 1, controller 20 communicates with multi-stage pump 100 via communication links 40 and 45. Communication links 40 and 45 may be a network (eg, Ethernet, wireless network, global area network, DeviceNet network, or other network known or developed in the prior art), bus (eg, SCSI bus), Or it can be another communication link. The controller 20 can be implemented as an on-board PCB board, a remote controller, or in any other suitable manner. The pump controller 20 can include suitable interfaces (eg, network interfaces, I / O interfaces, analog-to-digital converters, and other components) for communicating with the multi-stage pump 100. In addition, the pump controller 20 is not shown for the sake of brevity and includes various computer components known in the prior art, including a processor, memory, interface, display device, peripheral device, or other computer components. Can be included. The pump controller 20 controls the various valves and motors in the multi-stage pump so that the multi-stage pump accurately dispenses fluids including low viscosity fluids (ie, less than 100 centipoise) or other fluids. Can do. US Patent Application No. 60 / 741,657 by Cedrone et al., Entitled “I / O Interface System and Method for a Pump” (filed December 2, 2005), and US Patent Application No. _________ (__________) [ENTG18] -1], connecting the pump controller 20 to various interfaces and manufacturing tools using an I / O interface connector as disclosed in the name "I / O Systems, Methods and Devices for Interfacing a Pump Controller" All patent applications are hereby incorporated by reference in their entirety.

  FIG. 2 is a view showing the multistage pump 100. The multi-stage pump 100 includes a supply stage 105 and a separate distribution stage 110. From a fluid flow perspective, the filter 120 is located between the supply stage 105 and the distribution stage 110 to filter impurities from the process fluid. For example, multiple valves, including inlet valve 125, shut-off valve 130, barrier valve 135, purge valve 140, vent valve 145, and outlet valve 147, can control fluid flow through multi-stage pump 100. The dispensing stage 110 may further include a pressure sensor 112 that measures the pressure of the fluid in the dispensing stage 110. The pressure measured by the pressure sensor 112 can be used to control the speed of various pumps, as described below. Exemplary pressure sensors include ceramic and polymer piezoresistive and capacitive pressure sensors, including those manufactured by Metallux AG, Cove, Germany. According to one embodiment, the surface of the pressure sensor 112 that contacts the process fluid is a perfluoropolymer. The pump 100 can include additional pressure sensors, such as a pressure sensor that reads the pressure in the supply chamber 155.

  Supply stage 105 and distribution stage 110 may include a rolling diaphragm pump that feeds fluid into multi-stage pump 100. The supply stage pump 150 (“supply pump 150”) includes, for example, a supply chamber 155 that collects fluid, a supply stage diaphragm 160 that operates within the supply chamber 155 to discharge fluid, and a piston that operates the supply stage diaphragm 160. 165, a lead screw 170, and a step motor 175. The lead screw 170 is coupled to the step motor 175 via a nut, gear, or other mechanism to provide energy from the motor to the lead screw 170. According to one embodiment, supply motor 170 rotates the nut and then rotates lead screw 170 to actuate piston 165. Dispensing stage pump 180 (“dispensing pump 180”) can similarly include a dispensing chamber 185, a dispensing stage diaphragm 190, a piston 192, a lead screw 195, and a dispensing motor 200. The dispensing motor 200 can drive the lead screw 195 via a threaded nut (e.g., a Torlon or other material nut).

  According to other embodiments, supply stage 105 and dispensing stage 110 can be a variety of other pumps, including pneumatic or hydraulically operated pumps, hydraulic pumps, or other pumps. One embodiment of a multi-stage pump using a pneumatically operated pump for the feed stage and a stepper motor driven hydraulic pump is described in US patent application Ser. No. 11 / 051,576. It should be noted that the use of a motor in both stages provides the benefit of eliminating hydraulic piping, control systems, and fluids, thereby reducing space and potential leakage.

  Supply motor 175 and distribution motor 200 may be any suitable motor. According to one embodiment, the distribution motor 200 is a permanent-magnet synchronous motor (“PMSM”). PMSM used field-oriented control (“FOC”) in motor 200, controller-equipped multi-stage pump 100, or a separate pump controller (as shown in FIG. 1). It can be controlled by a digital signal processor (“DSP”) or other type of position / velocity control known in the prior art. The PMSM 200 may further include an encoder (eg, a fine line rotary position encoder) for feeding back the position of the distribution motor 200 in real time. Using the position sensor provides accurate and repeatable control of the position of the piston 192, resulting in accurate and repeatable control of fluid movement within the dispensing chamber 185. For example, according to one embodiment, a 2000 line encoder that provides 8000 pulses to the DSP can be used to accurately measure and control at a 0.045 degree rotation angle. In addition, the PMSM can operate at low speed with little or no vibration. The supply motor 175 can also be a PMSM or a step motor. It should also be noted that the feed pump can include a home sensor that indicates when the feed pump is in its reference position.

  FIG. 3A is a diagrammatic illustration of one embodiment of a pump assembly for multi-stage pump 100. The multi-stage pump 100 can include a distribution block 205 that defines various fluid flow paths through the multi-stage pump 100 and at least partially defines a supply chamber 155 and a distribution chamber 185. The distribution pump block 205 may be an integral block of PTFE, modified PTFE, or other material, according to one embodiment. Because these materials do not react or only minimally react with many process fluids, by using these materials, the flow path and pump chamber, along with the minimum additional hardware, can be distributed to the distribution block 205. Can be machined directly in. Thus, distribution block 205 reduces the need for piping by providing an integral fluid manifold.

  The distribution block 205 includes various external inlets and outlets, including, for example, an inlet 210 that receives fluid, a vent outlet 215 for discharging fluid into the vent segment, and a distribution outlet 220 through which fluid is distributed into the distribution segment. Can be included. The distribution block 205 does not include an external purge outlet in the embodiment of FIG. 3A (as shown in FIGS. 4A and 4B) such that the purged fluid is returned to the supply chamber. In embodiments, the fluid can be purged to the outside. In US Provisional Patent Application No. 60 / 741,667, filed by Iraj Gashgaee, entitled “O-Ring-Less Low Profile Fitting and Assembly Thereof” (filed December 2, 2005), fluid at the exterior entrance and exit of distribution block 205 One embodiment of a pipe fitting that can be used to connect to a conduit is disclosed and is incorporated herein by reference in its entirety.

  The distribution block 205 sends fluid to the supply pump, distribution pump, and filter 120. The pump cover 225 can prevent the supply motor 175 and distribution motor 200 from being damaged, and the piston housing 227 protects the piston 165 and piston 192, according to one embodiment of the present invention, polyethylene or other It can be formed of a polymer. The valve plate 230 can be configured to direct a fluid flow to various components of the multi-stage pump 100 (eg, inlet valve 125, shut-off valve 130, barrier valve 135, purge valve in FIG. 2). 140 and vent valve 145) provide a valve housing. According to one embodiment, each of inlet valve 125, shut-off valve 130, barrier valve 135, purge valve 140, and vent valve 145 is at least partially integrated with valve plate 230 and pressure or vacuum is applied to the corresponding diaphragm. Is a diaphragm valve that is opened or closed by being applied. In other embodiments, some valves can be external to the distribution block 205 or placed in additional valve plates. According to one embodiment, a sheet of PTFE is sandwiched between the valve plate 230 and the distribution block 205 to form the various valve diaphragms. The valve plate 230 includes a valve control inlet for each valve to apply pressure or vacuum to the corresponding diaphragm. For example, the inlet 235 corresponds to the barrier valve 135, the inlet 240 corresponds to the purge valve 140, the inlet 245 corresponds to the shut-off valve 130, the inlet 250 corresponds to the vent valve 145, and the inlet 255 corresponds to the inlet valve 125 (in this case, the outlet Valve 147 is external). The selective application of pressure or vacuum to the inlet opens and closes the corresponding valve.

  Valve control gas and vacuum are provided to the valve plate 230 via a valve control supply line 260, which passes from the valve control manifold (in the area under the top cover 263 or housing cover 225) through the distribution block 205. Extending to the valve plate 230. The valve control gas supply inlet 265 provides pressurized gas to the valve control manifold, and the vacuum inlet 270 provides vacuum (or low pressure) to the valve control manifold. The valve control manifold acts as a three-way valve to send pressurized gas or vacuum through supply line 260 to the appropriate inlet of valve plate 230 to activate the corresponding valve. In one embodiment, disclosed in U.S. Patent Application _________ by Gashgaee et al., Entitled "Fixed Volume Valve System" (the _________ application) [ENTG1770-1] (incorporated herein by reference in its entirety). Such valve plates can be used to reduce valve hold-up capacity, eliminate volume fluctuations due to vacuum fluctuations, relax vacuum requirements, and reduce stress on the valve diaphragm.

  FIG. 3B is a diagram illustrating another embodiment of the multi-stage pump 100. Many of the functions shown in FIG. 3B are similar to those described above in connection with FIG. 3A. Note that the embodiment of FIG. 3B includes several functions to prevent fluid drops from entering the area of the multi-stage pump 100 that houses the electronics. Fluid drops may occur, for example, when an operator attaches or detaches a tube to the inlet 210, outlet 215, or vent 220. The “drip-proof” feature prevents potentially harmful chemical drops from entering the pump, especially the electronics chamber, and necessarily makes the pump “waterproof” (eg, usable in fluids without leakage). Designed to be unnecessary. According to other embodiments, the pump can be completely sealed.

  According to one embodiment, the dispensing block 205 can include a vertically projecting flange or lip 272 that projects outwardly from the edge of the dispensing block 205 that contacts the top cover 263. On the top edge, according to one embodiment, the top of the top cover 263 is flush with the top surface of the lip 272. This allows drops near the top interface of the dispensing block 205 and top cover 263 to flow onto the dispensing block 205 rather than through the interface. On the side, the top cover 263 is flush with the bottom of the lip 272 or is offset inward from the outer surface of the lip 272. As a result, the droplets flow not to between the top cover 263 and the distribution block 205 but to the corner formed by the top cover 263 and the lip 272. In addition, a seal is disposed between the top edge of the top cover 263 and the back plate 271 so that droplets do not leak between the top cover 263 and the back plate 271.

  The distribution block 205 can also include an inclined feature 273 that includes an inclined surface defined within the distribution block 205 that is inclined downwardly away from the area of the pump 100 that houses the electronics. As a result, drops near the top of the dispensing block 205 are directed away from the electronics. In addition, the pump cover 225 is offset slightly inward from the outer edge of the distribution block 205 so that drops flowing on the sides of the pump 100 flow beyond the interface of the pump cover 225 and other parts of the pump 100. You can also.

  According to one embodiment of the present invention, wherever the metal cover interfaces with the distribution block 205, the vertical surface of the metal cover is offset slightly inward from the vertical surface of the corresponding distribution block 205 (e.g., 1/64 inch, 0.396875 mm). In addition, the multi-stage pump 100 can include seals, tilt features, and other features to prevent drops from entering the portion of the multi-stage pump 100 that houses the electronics. Further, as shown in FIG. 4A (discussed below), the backplate 271 can include functionality for an additional “drip-proof” multi-stage pump 100.

  FIG. 4A is a diagrammatic representation of one embodiment of a multi-stage pump 100 with a block 205 made transparent to show a defined fluid flow path. Distribution block 205 defines various chambers and fluid flow paths for multi-stage pump 100. According to one embodiment, supply chamber 155 and distribution chamber 185 can be machined directly into distribution block 205. In addition, various flow paths can be machined into the distribution block 205. A fluid flow path 275 (shown in FIG. 5C) extends from the inlet 210 to the inlet valve. A fluid flow path 280 extends from the inlet valve to the supply chamber 155 and completes the path from the inlet 210 to the supply pump 150. An inlet valve 125 in the valve housing 230 regulates the flow between the inlet 210 and the supply pump 150. The flow path 285 sends fluid from the supply pump 150 to the shut-off valve 130 in the valve plate 230. The output of the shut-off valve 130 is sent to the filter 120 via another path (not shown). Fluid flows from the filter 120 through a flow path that connects the filter 120 to the vent valve 145 and the barrier valve 135. The output of the vent valve 145 is sent to the vent outlet 215, and the output of the barrier valve 135 is sent to the distribution pump 180 via the flow path 290. The distribution pump can output fluid through the flow path 295 to the outlet 220 during the distribution segment or through the flow path 300 to the purge valve at the purge segment. During the purge segment, fluid can be returned to feed pump 150 via flow path 305. Since the fluid flow path can be formed directly in a block of PTFE (or other material), the distribution block 205 acts as piping for the process fluid between the various components of the multi-stage pump 100. Which eliminates or reduces the need for additional tubing. In other cases, a tube can be inserted into the distribution block 205 to define a fluid flow path. FIG. 4B is a diagrammatic representation of the distribution block 205 made transparent to show some of the internal flow paths, according to one embodiment.

  Returning to FIG. 4A, FIG. 4A includes a supply stage motor 190, a distribution pump 180, and a supply motor 200 and a valve control manifold 302 with the pump cover 225 and top cover 263 removed so that the supply pump 150 is visible. A multi-stage pump 100 is also shown. According to one embodiment of the invention, supply pump 150, distribution pump 180, and a portion of valve plate 230 use a bar (eg, a metal bar) inserted into a corresponding cavity in distribution block 205. , Can be connected to the distribution block 205. Each bar can include one or more threaded holes for receiving screws. As an example, the dispensing motor 200 and the piston housing 227 go through one or more screws (eg, screws 275 and screws 280) that thread through threaded holes in the dispensing block 205 and into corresponding holes in the bar 285, respectively. It can be placed on the distribution block 205. Note that this mechanism for the coupling element to the distribution block 205 is provided as an example, and any suitable attachment mechanism can be used.

  The back plate 271 may include an inwardly extending tab (eg, a bracket 274) on which the top cover 263 and the pump 225 rest, according to one embodiment of the present invention. Since the top cover 263 and the pump cover 225 overlap the bracket 274 (eg, at the bottom and back edges of the top cover 263 and the top and back edges of the pump cover 225), the bottom edge of the top cover 263 and the pump cover Prevent droplets from flowing into the area of the electronics in any space between the top edge of 225 or on the back edge of top cover 263 and pump cover 225.

  The manifold 302 may include a set of solenoid valves that selectively direct pressure / vacuum to the valve plate 230 according to one embodiment of the invention. When a particular solenoid is turned on and a vacuum or pressure is directed to the valve, the solenoid generates heat according to the implementation. According to one embodiment, the manifold 302 is separated from the distribution block 205 and in particular the distribution chamber 185, under the printed-circuit board (mounted on the backplate 271 and better shown in FIG. 4C). Placed on. The manifold 302 can be mounted on the bracket and can be further mounted on the back plate 271 or connected to the back plate 271. This helps to prevent the heat from the solenoids in the manifold 302 from affecting the fluid in the distribution block 205. The backplate 271 can be made of stainless steel, machined aluminum, or other materials that can dissipate heat from the manifold 302 and the PCB. In other words, the back plate 271 can act as a heat dissipation bracket for the manifold 302 and the PCB. The pump 100 can be further mounted on a surface or other structure that can conduct heat by the back plate 271. Accordingly, the back plate 271 and the structure to which it is attached acts as a heat sink for the manifold 302 and pump 100 electronics.

  FIG. 4C is a diagrammatic representation of the multi-stage pump 100 showing a supply line 260 for providing pressure or vacuum to the valve plate 230. As described in connection with FIG. 3, the valves in the valve plate 230 can be configured to allow fluid to flow to the various components of the multi-stage pump 100. Valve operation is controlled by a valve control manifold 302 that directs pressure or vacuum to the respective supply line 260. Each supply line 260 can include a mounting component (an example of a mounting component is shown at 318) having a small orifice. The orifice can be smaller in diameter than the corresponding supply line 260 to which the attachment 318 is attached. In one embodiment, the orifice diameter may be approximately 0.010 inches. Accordingly, the orifice of the attachment 318 can serve to limit the supply line 260. The orifice in each supply line 260 mitigates the effects of a sudden pressure difference between the application of pressure to the supply line and the application of vacuum, and thus the application of pressure to the valve and the application of vacuum. A smooth transition between is possible. That is, the orifice helps to mitigate the effect of pressure changes on the downstream valve diaphragm. As a result, the valve can be opened and closed more smoothly and slowly, the pressure transition that can be caused by opening and closing the valve can be made smoother, and the life of the valve itself can be extended.

  FIG. 4C also shows a PCB 397 to which the manifold 302 can be coupled. Manifold 302 receives signals from PCB board 397 and supplies vacuum / pressure directly to various supply lines 260 to control the valves of multi-stage pump 100 according to one embodiment of the invention. Open and close the solenoid. Also, as shown in FIG. 4C, the manifold 302 can be placed at the distal end of the PCB 397 from the distribution block 205 to reduce the effect of heat on the fluid in the distribution block 205. In addition, heat generating components can be located on the side of the PCB away from the distribution block 205, within a feasible range subject to PCB design and spatial constraints. Reduce the impact. Heat from manifold 302 and PCB 397 can be dissipated by backplate 271. FIG. 4D is a diagrammatic illustration of one embodiment of pump 100 with manifold 302 mounted directly on distribution block 205.

  Here, it will be useful to describe the operation of the multi-stage pump 100. During operation of multi-stage pump 100, the valves of multi-stage pump 100 are opened and closed to flow and restrict fluid to various portions of multi-stage pump 100. According to one embodiment, these valves can be pneumatically actuated (ie, gas driven) diaphragms that open and close based on pressure or vacuum asserts. It should be noted that any suitable valve can be used in other embodiments of the invention.

  In the following, an overview of the various stages of operation of the multi-stage pump 100 is provided. In addition, although the multistage pump 100 is not limited to this, Michael Clarke, Robert F., etc. Based on McLoughlin, and US Patent Application No. 11 / 502,729 by Marc Laverdière, entitled “Systems And Methods For Fluid Flow Control In Animulation Lithography System, dated 6th month” Control and sequence the valves and control pressure, each of which is incorporated herein by reference in its entirety. According to one embodiment, the multi-stage pump 100 includes a preparation segment, a dispensing segment, a fill segment, a prefiltration segment, a filtration segment, a vent segment, a purge segment, and a static purge segment. Can do. During the supply segment, the inlet valve 125 is opened and the supply stage pump 150 operates (eg, pulls) the supply stage diaphragm 160 to draw fluid into the supply chamber 155. When the supply chamber 155 is filled with a sufficient amount of fluid, the inlet valve 125 is closed. During the filtration segment, feed stage pump 150 operates feed stage diaphragm 160 to exhaust fluid from feed chamber 155. The isolation valve 130 and barrier valve 135 are opened to allow fluid to flow through the filter 120 to the distribution chamber 185. According to one embodiment, the isolation valve 130 is first opened (eg, in the “pre-filtration segment”) to create pressure in the filter 120 and then the barrier valve 135 is opened to allow fluid to flow into the distribution chamber. 185 can flow. According to other embodiments, both the shut-off valve 130 and the barrier valve 135 can be opened to operate the supply pump to create pressure on the distribution side of the filter. During the filtration segment, the dispensing pump 180 can be directed to its reference position. US Provisional Patent Application No. 60 / 630,384 by Laverdiere et al., “System and Method for a Variable Home Position Disposition System” (filed Nov. 23, 2004), and PCT Application No. PCT Application No. PCT No. 5 / PCT No. PCT No. 5 by PCT No. PCT Application No. PCT Application No. PCT Application No. Of the distribution pump as described in the No., name “System And Method For Variable Home Position Disposition System” (which is incorporated herein by reference in its entirety). The reference position provides the maximum usable capacity for the dispensing cycle, but is less than the maximum usable capacity that the dispensing pump can provide. Can be set. The reference position is selected based on various parameters for the dispensing cycle so as to reduce the unused holdup capacity of the multistage pump 100. The supply pump 150 may similarly be a reference position that provides a capacity that is less than the maximum usable capacity.

  At the beginning of the vent segment, the shut-off valve 130 is opened, the barrier valve 135 is closed, and the vent valve 145 is opened. In another embodiment, the barrier valve 135 can remain open in the vent segment and close at the end of the vent segment. If the barrier valve is opened during this time, the pressure in the distribution chamber, which can be measured by the pressure sensor 112, is affected by the pressure in the filter 120, so that the controller can grasp the pressure. Supply stage pump 150 applies pressure to the fluid and removes bubbles from filter 120 through an open vent valve 145. The feed stage pump 150 can be controlled to vent at a predetermined rate, and the venting rate can be lowered as the venting time is increased, thereby accurately controlling the amount of unnecessary venting. be able to. If the feed pump is a pneumatic pump, fluid flow restrictions can be imposed in the vent fluid path, and the air pressure applied to the feed pump is raised or lowered to maintain the "vent" set pressure Can provide some control of other uncontrolled methods.

  At the beginning of the purge segment, the shut-off valve 130 is closed and the barrier valve 135 is closed if open at the vent segment, the vent valve 145 is closed, the purge valve 140 is opened, and the inlet valve 125 is opened. The The distribution pump 180 applies pressure to the fluid in the distribution chamber 185 and vents bubbles through the purge valve 140. During the static purge segment, the dispense pump 180 is stopped, but the purge valve 140 remains open to continue air venting. Any excess fluid removed during the purge or static purge segment is routed from the multi-stage pump 100 (eg, returned to the fluid source or discarded) or recirculated to the supply stage pump 150. Can do. During the preparation segment, the inlet valve 125, the shutoff valve 130 and the barrier valve 135 are opened and the purge valve 140 is shut off so that the feed stage pump 150 can reach the ambient pressure of the source (eg, source bottle). Can do. According to another embodiment, all valves can be closed in the preparation segment.

  During the dispensing segment, the outlet valve 147 is opened and the dispensing pump 180 applies pressure to the fluid in the dispensing chamber 185. Since the outlet valve 147 can respond to control more slowly than the dispensing pump 180, the outlet valve 147 can be opened first and the dispensing motor 200 can be started after a predetermined time. This prevents the dispensing pump 180 from pushing fluid through the partially open outlet valve 147. In addition, this prevents the fluid from moving upward through the dispensing nozzle by the opening of the valve, and then prevents the fluid from moving forward by the operation of the motor. In other embodiments, outlet valve 147 can be opened and dispensing by dispensing pump 180 can begin at the same time.

  A suckback segment can be further performed to remove excess fluid in the dispensing nozzle. During the suckback segment, the outlet valve 147 can be closed and a secondary motor or vacuum can be used to draw excess fluid from the outlet nozzle. Alternatively, the outlet valve 147 can be left open and the dispensing motor 200 can be rotated back to return the fluid to the dispensing chamber. The suckback segment helps prevent excess fluid from dripping onto the wafer.

  Referring temporarily to FIG. 5, this figure shows the time adjustment of the valves and dispense motor for various operations of the multi-stage pump 100 of FIG. Although multiple valves are shown to be closed simultaneously during a segment change, valve closure may be slightly spaced (eg, 100 milliseconds) to reduce pressure spikes. it can. For example, between the vent segment and the purge segment, the shut-off valve 130 can be closed just before the vent valve 145. It should be noted that different valve timings may be used in various embodiments of the present invention. In addition, some of the segments can be performed together (eg, the filling / dispensing stage can be performed simultaneously, where both the inlet and outlet valves open during the dispensing / filling segment) be able to). Furthermore, it should be noted that a particular segment need not be repeated for each cycle. For example, the purge segment and the static purge segment are not performed every cycle. Similarly, vent segments are not performed every cycle.

  The opening and closing of various valves can cause pressure spikes in the fluid within the multi-stage pump 100. Since the outlet valve 147 is closed during the static purge segment, closing the purge valve 140 at the end of the static purge segment can, for example, increase the pressure in the distribution chamber 185. This can occur because a small amount of fluid can be drained when each valve is closed. More specifically, in many cases, before the fluid is dispensed from the chamber 185, the multi-stage pump 100 is purged and / or static so that it is not subject to sputtering or other perturbations during fluid dispensing. A purge cycle is used to purge air from the distribution chamber 185. Note that at the end of the static purge cycle, the purge valve 140 is closed to seal the dispensing chamber 185 in preparation for the beginning of dispensing. When the purge valve 140 is closed, an excess amount of fluid (approximately equal to the purge valve 140 hold-up volume) is forced into the distribution chamber 185, after which the pressure of the fluid in the distribution chamber 185 is reduced to the fluid pressure. Raise above reference pressure for dispensing. This excessive pressure (beyond the baseline) may cause problems with subsequent fluid distribution. These problems are adversely affected when low pressures are applied, as the pressure rise caused by the closure of the purge valve 140 may be at a greater rate than the reference pressure required for dispensing.

  More specifically, the pressure increase due to closure of the purge valve 140 results in “spitting” of the fluid onto the wafer, so that pressure does not decrease during subsequent dispensing segments, Double dispensing or other unwanted fluid dynamics may occur. In addition, since this pressure increase may not be constant during the operation of the multi-stage pump 100, these pressure increases may cause the amount of fluid dispensed or dispensed during subsequent dispensing segments. Other properties may vary. These variations in dispensing can result in wafer scrap and wafer reprocessing. Embodiments of the present invention compensate for pressure increases due to the closure of various valves in the system to achieve the desired starting pressure for initiating the dispensing segment and should be achieved in the dispensing chamber 185 prior to dispensing. Allowing all reference pressures compensates for head pressure differences and other differences in equipment between systems.

  In one embodiment, during the static purge segment, the dispensing motor 200 is reverse rotated to return the piston 192 a predetermined distance to compensate for the unnecessary pressure rise on the fluid in the dispensing chamber 185 to provide a barrier valve 135. , Purge valve 140, and / or any pressure increase caused by other sources that may cause a pressure increase in distribution chamber 185 may be compensated. The pressure in the distribution chamber 185 was determined by US Patent Application No. 11 / 292,559 by George Gonella and James Cedrone, entitled “System and Method for Control of Fluid Pressure” (filed December 2, 2005), and George Gonell. No. 11 / 364,286 by James Cedrone, named “System and Method for Monitoring Operation of a Pump” (filed Feb. 28, 2006), both incorporated herein. As such, it can be controlled by adjusting the speed of the supply pump 150.

  Accordingly, embodiments of the present invention provide a multi-stage pump characterized by gentle fluid handling. By compensating for pressure fluctuations in the dispensing chamber before the dispensing segment, potentially damaging pressure spikes can be avoided or reduced. Embodiments of the present invention can also use other pump control mechanisms and valve timing to help reduce the adverse effects of pressure on the process fluid and pressure fluctuations.

  To that end, attention is focused on systems and methods for compensating for pressure rises or drops that may occur in various enclosed spaces of the pump apparatus. Embodiments of the present invention increase or decrease the pressure in the chamber of the pump device by operating the pump means of the pump device to adjust the volume of the chamber to compensate for the pressure increase or decrease in the chamber. Can be compensated for. More specifically, in one embodiment, in order to compensate for unwanted pressure rises on the fluid in the distribution chamber, the distribution motor is rotated back to return the piston to compensate for any pressure increase in the distribution chamber. .

  These pressure fluctuation reductions can be better understood with reference to FIG. 6, which illustrates the pressure profile in the distribution chamber 185 for operation of a multi-stage pump, according to one embodiment of the present invention. It is a figure which shows an example. At point 440, dispensing begins and dispensing pump 180 pushes fluid out of the outlet. The distribution ends at point 445. Since the dispensing pump 180 is generally not involved at this stage, the pressure in the dispensing chamber 185 remains substantially constant during the filling phase. At point 450, the filtration phase begins and the feed phase motor 175 rotates forward at a predetermined speed to push fluid out of the feed chamber 155. As can be seen from FIG. 6, the pressure in the distribution chamber 185 begins to rise and reaches a predetermined set point at point 455. When the pressure in the distribution chamber 185 reaches the set value, the distribution motor 200 reverses at a constant speed, increasing the available capacity in the distribution chamber 185. In the relatively flat portion of the pressure profile between point 455 and point 460, the speed of the supply motor 175 is increased when the pressure falls below the set value and is reduced when the set value is reached. Thereby, the pressure in the distribution chamber 185 is maintained at a substantially constant pressure. At point 460, the dispensing motor 200 reaches its reference position and the end of the filtration stage. The sudden pressure spike at point 460 is caused by the closure of the barrier valve 135 at the end of filtration.

  After the vent and purge segment and before the end of the static purge segment, the purge valve 140 is closed and begins to produce a pressure spike at point 1500 in the pressure profile. As shown in the figure, between points 1500 and 1502 of the pressure profile, the pressure in the dispensing chamber 185 can increase significantly due to this closure. The pressure increase due to the closure of the purge valve 140 is usually unstable and depends on the temperature and fluid viscosity of the system used with the multi-stage pump 100.

  In order to compensate for the pressure increase that occurs between points 1500 and 1502, the dispensing motor 200 is rotated back to return the piston 192 a predetermined distance to provide a barrier valve 135, purge valve 140, and / or other source. Any pressure increase that occurs can be compensated. In some cases, the purge valve 140 can be closed after some time, which may be desirable for a certain time delay before the dispensing motor 200 is reverse rotated. Thus, the time between points 1500 and 1504 on the pressure profile reflects the delay between the signal to close the purge valve 140 and the reverse rotation of the dispensing motor 200. This delay time is sufficient to allow the purge valve 140 to be fully closed and to stabilize the pressure in the dispensing chamber 185, and can be about 50 milliseconds.

  Since the hold-up capacity of the purge valve 140 can be a known amount (eg, within manufacturing tolerances), the distribution motor 200 is rotated backward to return the piston 192a to the compensation distance, and the capacity of the distribution chamber 185 is reduced to the purge valve 140. Can be increased approximately equal to the hold-up capacity. Since the dimensions of the distribution chamber 185 and the piston 192 are also known quantities, it is possible to reversely rotate the distribution motor 200 by a specific motor increment, and reversely rotate the motor 200 by this motor increment. As a result, the capacity of the distribution chamber 185 is increased by the hold-up capacity of the purge valve 140.

  By the action of returning the piston 192 due to the reverse rotation of the distribution motor 200, the pressure in the distribution chamber 185 drops from the point 1504 to near the reference pressure necessary for distribution at the point 1506. In many cases, this pressure correction may be sufficient to obtain a satisfactory distribution in subsequent distribution stages. Depending on the type of motor used in the distribution motor 200 or the type of valve used in the purge valve 140, the distribution motor 200 is rotated in the reverse direction so as to increase the capacity of the distribution motor 185. There may be a space, that is, “backlash” in the drive mechanism of the motor 200. This “backlash” may exist between components of the dispensing motor 200, such as a motor nut assembly, when the dispensing motor 200 is actuated forward during the dispensing segment to push fluid from the dispensing pump 180. A specific amount of slack or space that may need to be removed before the drive assembly of the dispensing motor 200 can be physically activated so that the piston 192 moves. Since the amount of backlash can vary, it can be difficult to compensate for this backlash when determining how far to move the piston 192 to obtain the desired dispense pressure. Thus, this backlash in the drive assembly of dispense motor 200 may cause variations in the amount of fluid dispensed into each dispense segment.

  As a result, the last motion of the dispensing motor 200 is forwarded before the dispensing segment so that the amount of backlash in the drive assembly of the dispensing motor 200 is substantially negligible or reduced to a non-existing level. It may be desirable to be Thus, in some embodiments, to compensate for unwanted backlash in the drive motor assembly of the dispense pump 200, the dispense motor 200 is reverse rotated to return the piston 192 a predetermined distance to provide a barrier valve 135, Any pressure increase caused by the purge valve 140 and / or other sources that may cause a pressure increase in the distribution chamber 185 may be compensated, and the piston 192 may be returned by an overshoot distance. It is possible to reverse the dispense motor 192 to add an overshoot capacity to the dispense chamber 185. Distributing motor 200 can then operate in the forward direction to move piston 192 in the forward direction by an amount approximately equal to the overshoot distance. This provides approximately the desired reference pressure in the dispensing chamber 185, and the final motion of the dispensing motor 200 prior to dispensing is forward, removing virtually any backlash from the drive assembly of the dispensing motor 200.

  Still referring to FIG. 6, as described above, a pressure spike starting at point 1500 in the pressure profile can be caused by the closure of the purge valve 140. In order to compensate for the pressure rise that occurs between points 1500 and 1502, the dispensing motor 200 is reverse rotated after a delay to return the piston 192 back a predetermined distance to close the purge valve 140 (and / or other source). It is possible to compensate for the pressure rise caused by and the further overshoot distance. As described above, the compensation distance can increase the volume of the distribution chamber 185 to an amount approximately equal to the hold-up volume of the purge valve 140. The overshoot distance can increase the capacity of the distribution chamber 185 to an amount approximately equal to the hold-up capacity of the purge valve 140, or can be increased to a greater or lesser amount, depending on the particular implementation. It is.

  Due to the action of returning the piston 192 by the compensation distance and the overshoot distance due to the reverse rotation of the distribution motor 200, the pressure in the distribution chamber 185 drops from the point 1504 to the point 1508. Distributing motor 200 then operates in the forward direction to move piston 192 in the forward direction by an amount approximately equal to the overshoot distance. In some cases, it may be desirable to be able to stop the dispensing motor 200 almost completely before operating the dispensing motor 200 in the forward direction, and this delay may be about 50 milliseconds. Due to the action of the forward rotation of the piston 192 by the forward rotation operation of the distribution motor 200, the pressure in the distribution chamber 185 increases from the point 1510 to near the reference pressure required for distribution at the point 1512, while before the distribution segment. Most of the backlash is removed from the drive assembly of the dispense motor 200 so that the final movement of the dispense motor 200 is forward. The reverse and forward operation of the dispensing motor 200 at the end of the static purge segment is shown in the time adjustment diagram of FIG.

  Embodiments of the present invention can be more clearly described with reference to FIG. 7, which illustrates a distribution chamber in a particular segment operating a multi-stage pump, according to one embodiment of the present invention. FIG. 185 shows an example of a pressure profile at 185. Line 1520 shows the reference pressure required for fluid distribution, which can be any desired pressure, but is generally 0 psi (eg, gauge), or atmospheric pressure. At point 1522, during the purge segment, the pressure in the distribution chamber 185 may be slightly higher than the reference pressure 1520. Dispensing motor 200 may stop at the end of the purge segment and the pressure in dispensing chamber 185 may begin to decrease at point 1524 and decrease to approximately reference pressure 1520 at point 1526. Note that before the static purge segment ends, a valve in the pump 100, such as the purge valve 140, can be closed, causing a pressure spike between points 1528 and 1530 of the pressure profile.

  The dispense motor 200 can then be rotated back to operate the piston 192 by a compensation distance and an overshoot distance (as described above), and the pressure in the dispense chamber 185 can be reduced to a point 1532 in the pressure profile. 1534 and the reference pressure 1520 or less. To return the pressure in the dispensing chamber 185 to approximately the reference pressure 1520 and remove backlash from the drive assembly of the dispensing motor 200, the dispensing motor 200 can be operated in a forward direction approximately equal to the overshoot distance. This action causes the pressure in dispensing chamber 185 to return to reference pressure 1520 between points 1536 and 1538 of the pressure profile. Thus, the pressure in the dispensing chamber 185 returns to substantially the reference pressure required for dispensing and the backlash can be removed from the drive assembly of the dispensing motor 200 to achieve the desired dispensing in the subsequent dispensing segment. Is possible.

  Although the above-described embodiments of the present invention have been described primarily with respect to compensation for pressure rise caused by closing the purge valve during a static purge segment, these same techniques have been applied to operate the multi-stage pump 100. It is possible to compensate for the pressure increase or decrease caused by almost any stage, whether external or internal to the multi-stage pump 100, and in particular the flow to / from the distribution chamber 185. It will be apparent that it can be useful in correcting pressure fluctuations in the distribution chamber 185 caused by opening and closing valves in the path.

  In addition, using these same techniques, it is possible to achieve the desired reference pressure in the distribution chamber 185 by compensating for variations in other devices used with the multi-stage pump 100. In order to better compensate for these differences in equipment or other variations in the process, identification of the invention, such as equipment used inside or outside the environment or multi-stage pump 100, the reference pressure required for the distribution chamber 185 The side surface or deformation, compensation distance, overshoot distance, delay time, and the like can be set by the user of the pump 100.

  Further, embodiments of the present invention can use pressure transducer 112 to achieve a desired reference pressure in dispensing chamber 185 as well. For example, until the desired reference pressure (measured by pressure transducer 112) in distribution chamber 185 is achieved to compensate for any pressure rise caused by closure of purge valve 140 (and / or other sources). The piston 192 can be returned (or advanced). Similarly, prior to dispensing, to reduce the amount of backlash in the drive assembly of dispensing motor 200 to a level that is substantially negligible or nonexistent, piston 193 is adjusted so that the pressure in dispensing chamber 185 is at the reference pressure. It is possible to return to below and then move forward until the pressure in the dispensing chamber 185 rises to the reference pressure required for dispensing.

  In addition to being able to compensate for pressure fluctuations in the fluid as described above, in addition, so that pressure spikes in the process fluid, or other pressure fluctuations, do not close the valve and create an entrainment space, Moreover, it can reduce by preventing a valve from opening between mixing spaces. During the entire dispensing cycle (eg, from dispensing segment to dispensing segment) of the multi-stage pump 100, the position of the valves within the multi-stage pump 100 can often change. During these countless changes, unnecessary pressure spikes and pressure drops may occur. These pressure fluctuations not only harm sensitive process chemicals, but in addition, the opening and closing of these valves can cause disruptions or changes in the fluid distribution. For example, a sudden pressure rise in the holdup volume caused by the opening of one or more internal valves connected to the distribution chamber 185 causes a corresponding pressure drop in the fluid in the distribution chamber 185, In some cases, bubbles may be generated, and these may affect the subsequent distribution.

  In order to improve the pressure fluctuations caused by the opening and closing of the various valves in the multi-stage pump 100, the opening and closing of the various valves and / or the operation and deactivation of the motor can be tailored to reduce these pressure spikes. . Overall, to avoid pressure fluctuations based on embodiments of the present invention, if possible, never close the valve so that there is no closed or mixed space in the fluid path, and this is important However, if it can be avoided, the valve is not opened between the two mixing spaces. Conversely, if there is an open fluid path to a region outside the multi-stage pump 100, or if there is an open fluid path to the atmosphere or conditions outside the multi-stage pump 100 (eg; outlet valve 147, vent Any valve opening should be avoided (except when the valve 145 or the inlet valve 125 is opened).

  Another way to represent general guidelines for opening and closing valves in the multi-stage pump 100 according to embodiments of the present invention is the change in capacity (opened) that may result from valve opening during operation of the multi-stage pump 100. The barrier valve only when an external valve such as the inlet valve 125, vent valve 145, or outlet valve 147 is opened to discharge any pressure change caused by the internal valve holdup capacity). Opening a valve inside the multi-stage pump 100 such as 135 or purge valve 140. These guidelines also contemplate other aspects, and when opening a valve in the multi-stage pump 100, the valve must be opened from the outside to the inside (ie, the outside valve is opened before the inside valve). On the other hand, when closing the valve in the multi-stage pump 100, the valve must be closed from the inside to the outside (ie, the inner valve must be closed before the outer valve). .

  In addition, in some embodiments, certain valves may be fully opened and closed before another change occurs (eg, valve opening or closing, motor start or stop) occurs (eg, is initiated). The specific change to ensure that the motor is fully started or stopped, or that the pressure in the system or part of the system is at approximately zero psi (eg, gauge) or non-zero level. Sufficient time is used during In many cases the delay must be between 100 and 300 milliseconds in order to be able to open and close the valves in the multistage pump 100 almost completely, but the actual delay to be used for a particular application or implementation of these techniques. May depend at least in part on the viscosity of the fluid being utilized by the multi-stage pump 100, along with a wide variety of factors.

  The above guidelines can be better understood with reference to FIGS. 8A and 8B, which serve to improve pressure fluctuations during operation of the multi-stage pump 100. FIG. 6 illustrates one embodiment of valve and motor timing for various segments of operation. 8A and 8B are not drawn to scale, and regardless of the drawing of these figures, each numbered segment has a different or unique length of time (including zero time). And the length of each of the labeled segments depends on the user's technique implemented, the type of valve used in the multi-stage pump 100 (eg, how long it takes to open and close these valves). Note that it can be based on a wide variety of factors such as

  Referring to FIG. 8A, at time 2010, the ready segment signal may indicate that multi-stage pump 100 is ready to dispense, some time later than time 2010, one or more at time 2020. Can be transmitted to open the inlet valve 125, operate the dispensing motor 200 in the forward direction to dispense fluid, and reversely rotate the filling motor 175 to draw fluid into the filling chamber 155. is there. After time 2020 but before time 2022 (eg, during segment 2), the outlet valve 147 is opened so that a signal can be sent to allow fluid to be dispensed from the outlet valve 147.

By reading the present disclosure, the time adjustment of the valve signal and the motor signal can be varied based on the time required to operate the various valves or motors, and this approach can be used with the multi-stage pump 100 or other. It will be clear that it is implemented in relation to other factors. For example, in FIG. 8A, in this embodiment, the outlet valve 147 can operate faster than the distribution motor 200, and therefore, after sending a signal to operate the distribution motor 200 in the forward direction, the outlet valve 147 is turned on. It is possible to send a signal to open, so the opening of the outlet valve 147 and the operation of the dispensing motor 200 are timed so that they substantially match to achieve a better dispensing. It is desirable. It should be noted that other valves and motors may have different operating speeds, etc., so different time adjustments may be used for these different valves and motors. For example, a signal to open the outlet valve 147 can be transmitted earlier or substantially simultaneously with a signal to activate the dispensing motor 200, and similarly, a signal to close the outlet valve 147 can be transmitted to the dispensing motor 200. Can be transmitted earlier, later than or simultaneously with the signal to stop the transmission.

  Accordingly, it is possible to dispense fluid from the multi-stage pump 200 between times 2020 and 2030. Based on the approach being performed by the multi-stage pump 200, the speed of operation of the dispensing motor 200 is between the times 2020 and 2030 so that different amounts of fluid can be dispensed at different points between the times 2020 and 2030. (E.g., in each of segments 2-6). For example, the dispensing motor 200 operates faster between the segments 2 than during the segments 6 and correspondingly more fluid is dispensed from the multistage pump 200 in the segments 2 than in the segments 6. It is possible to operate the distribution motor based on a polynomial function. After the dispensing segment occurs, a signal is sent before time 2030 to close outlet valve 147, and at a subsequent time 2030, a signal is sent to stop dispensing motor 200.

  Similarly, between times 2020 and 2050 (eg, segments 2-7), the fill motor 175 can be rotated backwards to fill the supply chamber 155 with fluid. Then, at time 2050, a signal is sent to stop the filling motor 175, after which the filling segment ends. Entry between time 2050 and time 2060 (eg, segment 9, delay 0) before other actions are taken to apply pressure to the fill champ 155 to return it to approximately zero psi (eg, gauge). It is possible to keep the valve open. In one embodiment, this delay can be about 10 milliseconds. In another embodiment, the time between time 2050 and time 2060 can be varied and can be based on an indication of the pressure in the fill chamber 155. For example, a pressure transducer can be used to measure the pressure in the fill chamber 155. Segment 10 can begin at time 2060 when the pressure transducer indicates that fill chamber 155 has reached zero psi.

  Then, at time 2060, a signal is sent to open the shut-off valve 130, and after a suitable delay (eg, about 250 milliseconds) long enough to fully open the shut-off valve 130, the signal is sent at time 2070. Then, the barrier valve 135 is opened. Again, after a suitable delay (eg, about 250 milliseconds) long enough to fully open the barrier valve 135, at time 2080, a signal is sent to close the inlet valve 125. At a time 2090, a signal may be sent to activate the fill motor 175 after a suitable delay (e.g., about 350 milliseconds) sufficient to completely close the inlet valve 125; A signal is sent to cause dispensing motor 200 to operate so that fill motor 175 is activated during filtration and filtration segments (eg, segments 13 and 14 and dispense motor 200 is activated during filtration segments (eg, segment 14). The time between time 2090 and time 2010 is a pre-filter segment or set time for motor operation to allow the pressure of the filtered fluid to reach a predetermined set point Alternatively, it can be a set distance or determined using a pressure transducer as described above.

  Alternatively, the pressure of the fluid can be measured using a pressure transducer, and the filtration segment 14 is started at time 2100 when the pressure transducer indicates that the pressure of the fluid has reached a set point. Is possible. Embodiments of these processes are described in US Patent Application No. 11 / 292,559 by George Gonella and James Cedrone, named “System and Method for Control of Fluid Pressure” (filed December 2, 2005), and George Gonella. No. 11 / 364,286, James Cedrone, entitled “System and Method for Monitoring Operation of a Pump”, both of which are incorporated herein by reference.

  After the filtration segment, at time 2110, one or more signals are sent to stop the fill motor 175 and the dispense motor 200. The length between time 2100 and time 2110 (eg, filtration segment 14) can be varied based on the desired filtration rate, speed of fill motor 175 and dispense motor 200, fluid viscosity, and the like. In one embodiment, the filtration segment may end at time 2110 when the dispensing motor 200 has reached the reference position.

  Although no time may be required (eg, no delay), after a delay suitable to completely stop the fill motor 175 and dispensing motor 200, a signal is sent at time 2120 to vent valve 145. Open. Turning to FIG. 8B, after a suitable delay (eg, about 225 milliseconds) to fully open the vent valve 145, a signal is sent to the fill motor 175 at time 2130 to identify the vent segment (eg, segment 17). It is possible to operate the step motor 175 for During the vent segment, it is possible to keep the barrier valve 135 open during the vent segment so that the pressure of the fluid in the multi-stage pump 100 is monitored by the pressure transducer 112, but the barrier valve 135 is At 2130, it may be closed before the vent segment begins.

  At the end of the vent segment, at time 2140, a signal is sent to stop the fill motor 175. If necessary, provide a delay (eg, about 100 milliseconds) between times 2140 and 2142 to properly dissipate the fluid pressure if, for example, the fluid pressure in the vent segment is high Is possible. In one embodiment, a time between times 2142 and 2150 can be used to zero pressure transducer 112, and this time can be about 10 milliseconds.

Then, at time 2150, a signal is sent to close the barrier valve 135 . After time 2150, a suitable delay (approximately 250 milliseconds) is provided so that the barrier valve 135 can be completely closed. Then, at time 2160, a signal is sent to close shut-off valve 130, and after a suitable delay (eg, about 250 milliseconds) to completely shut off shut-off valve 130, at time 2170, the signal is sent The vent valve 145 is closed. A suitable delay (e.g., about 250 milliseconds) is provided to allow the vent valve 145 to be fully closed, and then at time 2180, a signal is sent to open the inlet valve 125 and the inlet valve 125 After a delay suitable for fully opening (approximately 250 milliseconds), at time 2190, a signal is sent to open the purge valve 140.

  After a suitable delay (eg, about 250 milliseconds) to fully open vent valve 145, at time 2200, a signal is sent to start dispense motor 200 for the purge segment (eg, segment 25). After a time for the purge segment, which may depend on the technique, at time 2210, a signal is sent to stop the dispensing motor 200 and terminate the purge segment. Between times 2210 and 2212, a sufficient amount of time (e.g., measured using predetermined or pressure transducer 112) (e.g., measured using predetermined or pressure transducer 112) such that the pressure in distribution chamber 185 can stabilize at approximately zero psi. , Approximately 10 milliseconds). Subsequently, at time 2220, a signal may be sent to close the purge valve 140, and after providing a sufficient delay (eg, 250 milliseconds) to fully close the purge valve 140, the time At 2230, a signal can be sent to close the inlet valve 125. After actuating dispensing motor 200 to compensate for any pressure fluctuations caused by valve closure in multistage pump 100 (as described above), multistage pump 100 is ready to dispense again at time 2010. It is possible.

  Note that there may be some delay between the preparation segment and the distribution segment. Barrier valve 135 and shut-off valve 130 can be closed when multi-stage pump 100 enters the preparation segment, so that subsequent multi-stages regardless of whether dispensing is initiated during or after filling. It is possible to direct fluid to the fill chamber 155 without affecting the pump distribution.

  The filling of the filling chamber while the multistage pump 100 is in a ready state can be more clearly described with reference to FIGS. 9A and 9B, which show the pressure during operation of the multistage pump 100. FIG. 5 shows another embodiment of valve and motor timing for various segments of operation of multi-stage pump 100 that serve to improve variability.

  Referring to FIG. 9A, at time 3010, the ready segment signal can indicate that multi-stage pump 100 is ready to dispense, and at some later time, at time 3012, the signal is sent and exited. The valve 147 can be opened. After a suitable delay to open the outlet valve 147, at time 3020, one or more signals are transmitted to operate the dispensing motor 200 in a forward direction to dispense fluid from the outlet valve 147 and also to a filling motor 175 is reversed to draw fluid into the fill chamber 155 (the inlet valve 125 can remain open from its previous fill segment and is described in detail below). At time 3030, a signal is transmitted to stop dispensing motor 200, and at time 3040, a signal is transmitted to close outlet valve 147.

  By reading the present disclosure, the time adjustment of the valve signal and the motor signal can be varied based on the time required to operate the various valves or motors, and this approach can be used with the multi-stage pump 100 or others. It will be clear that it is implemented in relation to other factors. For example, in this embodiment (as shown in FIG. 8A), the outlet valve 147 can operate faster than the distribution motor 200, so after sending a signal to operate the distribution motor 200 in the forward direction. , It is possible to send a signal to open the outlet valve 147, so the opening of the outlet valve 147 and the operation of the dispensing motor 200 are substantially matched to achieve a better dispensing. It is desirable to adjust the time. It should be noted that other valves and motors may have different operating speeds, etc., so different time adjustments may be used for these different valves and motors. For example, a signal to open the outlet valve 147 can be transmitted earlier than or substantially simultaneously with a signal to activate the dispensing motor, and similarly, a signal to close the outlet valve 200 causes the dispensing motor 200 to close. It is possible to transmit earlier, later or simultaneously with the signal to be stopped.

Accordingly, it is possible to dispense fluid from the multi-stage pump 200 between times 3020 and 3030. Based on the approach being performed by the multi-stage pump 200, the speed of operation of the dispensing motor 200 is between time 3020 and 3030 so that different amounts of fluid can be dispensed at different points between times 3020 and 3030. (E.g., in each of segments 2-6). For example, the distribution motor 200 can be operated more rapidly between segments 2 than during segment 6 and correspondingly more fluid can be distributed in segment 2 than in segment 6. It is possible to operate based on After the dispensing segment occurs, a signal is sent before time 3030 to close outlet valve 147 and at a subsequent time 3030 , a signal is sent to stop dispensing motor 200.

  Similarly, between the times 3020 and 3050 (eg, segments 2-7), the fill motor 175 can be reversed to fill the supply chamber 155 with fluid. Then, at time 3050, a signal is sent to stop the fill motor 175, after which the fill segment ends. Inlet valve between time 3050 and time 3060 (eg, segment 9, delay 0) before any other action is taken to apply pressure to fill chamber 155 to return to approximately zero psi (eg, gauge). Can be left open. In one embodiment, this delay can be about 10 milliseconds. In another embodiment, the time between time 3050 and time 3060 can be varied and can be based on an indication of the pressure in the fill chamber 155. For example, a pressure transducer can be used to measure the pressure in the fill chamber 155. Segment 10 can begin at time 3060 when the pressure transducer indicates that fill chamber 155 has reached zero psi.

  Then, at time 3060, a signal is transmitted to open shut-off valve 130, and at time 3070, a signal is transmitted to open barrier valve 135. Then, at time 3080, a signal may be sent to close the inlet valve 125, after which time 3090 may be sent to activate the fill motor 175, and at time 3100, pre-filtration and A signal can be sent to activate the dispensing motor 200 such that the fill motor 175 is activated during the filtration segment and the dispense motor 200 is activated during the filtration segment.

  After the filtration segment, at time 3110, one or more signals are sent to stop the fill motor 175 and the dispense motor 200. At time 3120, a signal is sent to open vent valve 145. Turning to FIG. 9B, at time 3130, a signal can be sent to the fill motor 175 to activate the step motor 175 for the vent segment. At the end of the vent segment, at time 3140, a signal is sent to stop the fill motor 175. Then, at time 3150, a signal is sent to close barrier valve 125, at time 3160, a signal is sent to close shut-off valve 130, and at time 3170, vent valve 145 is closed.

  At time 3180, a signal is sent to open the inlet valve 125, and then at time 3190, a signal is sent to open the purge valve 140. Then, at time 3200, a signal can be sent to the distribution motor 200 to start the distribution motor 200 for the purge segment, and after the purge segment, at time 3210, a signal is sent to stop the distribution motor 200. can do.

  Subsequently, at time 3220, a signal may be sent to close purge valve 140, and then at time 3230, a signal may be sent to close inlet valve 125. After actuating dispensing motor 200 to compensate for any pressure fluctuations caused by valve closure in multistage pump 100 (as described above), multistage pump 100 is ready to dispense again at time 3010. It is possible.

At time 3010, when multi-stage pump 100 enters the preparation segment, fluid is drawn into fill chamber 155 while a signal is sent to open inlet valve 125 so that multi-stage pump 100 is ready. However, it is possible to reversely rotate the filling motor 175 by transmitting another signal. During the preparation segment, the filling chamber 155 is filled with fluid, but the barrier valve 135 and the shutoff valve 130 are closed to substantially separate the filling chamber 155 from the dispensing chamber 185, so that this filling is performed on the preparation segment. At any point following entry, there is no impact on the ability of the multi-stage pump 100 to dispense fluid. Furthermore, if dispensing is initiated before filling is complete, this filling can continue substantially simultaneously with the dispensing of fluid from the multi-stage pump 100.

  When the multi-stage pump 100 first enters the preparation segment, the pressure in the dispensing chamber 185 can be approximately the desired pressure for the dispensing segment. Note that since there is some delay between entering the preparation segment and the start of the dispensing segment, the pressure in the dispensing chamber 185 will cause the characteristics of the dispensing stage diaphragm 190 in the dispensing chamber 185, temperature changes, or Based on various other factors, it can vary in the preparation segment. As a result, when the dispensing segment is initiated, the pressure in the dispensing chamber 185 may drift relatively greatly from the reference pressure required for dispensing.

This drift can be explained more clearly with reference to FIGS. 10A and 10B. FIG. 10A is a diagram illustrating an example of a pressure profile in the distribution chamber 185 showing the pressure drift in the distribution chamber during the preparation segment. As described above with reference to FIGS. 9A and 9B , at approximately point 4010, corrections for any pressure changes caused by valve operation or another cause may be made. This pressure correction can correct the pressure in dispensing chamber 185 to near the reference pressure (represented by line 4030) required for dispensing at point 4020, at which point multistage pump 100 is ready. It is possible to enter a segment. As shown, after entering the preparation segment at approximately point 4020, the pressure in dispensing chamber 185 may increase uniformly due to various factors as described above. Then, when a subsequent dispensing segment occurs, the pressure drifting from this reference pressure 4030 may cause insufficient dispensing.

  In addition, the time delay between entry into the preparation segment and subsequent distribution segments can vary, and the pressure drift in the distribution chamber 185 can be correlated with the time of delay, so between different delays. Due to the different amounts of drift that occur in each, the distribution that occurs in each successive distribution segment may differ. Thus, this pressure drift may also affect the repeat of accurate dispensing of the multi-stage pump 100 and, as a result, may hinder the use of the multi-stage pump 100 in process process iterations. Therefore, substantially maintaining the reference pressure during the preparatory segment of the multi-stage pump 100 improves the reproducibility of distribution in and subsequent distribution segments, while achieving acceptable fluid dynamics. It may be desirable to do so.

  In one embodiment, to maintain a reference pressure during the preparation segment, the dispensing motor 200 can be controlled to compensate for upward (or downward) pressure drift that may occur in the dispensing chamber 185. More specifically, the dispense motor 200 can be controlled to maintain a substantially reference pressure within the dispense chamber 185 using “dead band” closed loop pressure control. Referring temporarily to FIG. 2, the pressure sensor 112 can report pressure readings to the pump controller 20 at regular intervals. Pump controller 20 can send a signal to dispense motor 200 to move dispense motor 200 if the reported pressure deviates from the desired reference pressure by a certain amount or tolerance. By reversing (or forward) this dispensing motor by the minimum distance detectable by motor 20 (motor increment), piston 192 and dispensing stage diaphragm 190 are returned to cause the pressure in dispensing chamber 185 to be reduced accordingly. It is possible to descend (or ascend) by the amount.

  The frequency at which the pressure sensor 112 can sample and report the pressure in the dispensing chamber 185 can be somewhat faster compared to the operating speed of the dispensing motor 200 so that another pressure measurement can be made by the pump controller 20. Before the value is received or processed, the pump controller 20 is activated by the pressure sensor 112 during a particular time window that sends a signal to the dispense motor 200 so that the dispense motor 200 can complete its movement. It is possible to either not process the reported pressure measurements or to disable the pressure sensor 112. Alternatively, the pump controller 20 can be waited until the dispensing motor 200 detects that it has completed its movement before processing the pressure measurement reported by the pressure sensor 112. In many embodiments, the sampling interval at which the pressure sensor 112 samples the pressure in the dispensing chamber 185, and the measurement of this pressure measurement may be about 30 kHz, about 10 kHz, or other intervals. .

  The above-described embodiment is not without problems. In some cases, one or more of these embodiments may exhibit significant variation during distribution when the time delay between entry into the ready segment and subsequent distribution segments varies as described above. is there. To some extent, these problems are reduced and reproducibility is improved by using a fixed time interval between entry into the preparation segment and subsequent distributions, but this may be the case if you are implementing a specific process. It is not always suitable.

  In order to maintain substantially the reference pressure during the preparation segment of the multi-stage pump 100 while increasing dispensing repeatability, in some embodiments, the dispensing motor 200 is controlled using closed loop pressure control. The pressure drift that can occur in the distribution chamber 185 can be compensated. The pressure sensor 112 can report pressure readings to the controller 20 at regular intervals (as described above, in one embodiment, approximately 30 kHz, approximately 10 kHz, or another interval). If the reported pressure is higher (or lower) than the desired reference pressure, the pump controller 20 sends a signal to the distribution motor 200 to reverse (or forward) the distribution motor 200 by the motor increment. ) To return the piston 192 and the dispensing stage diaphragm 190 to lower (or increase) the pressure in the dispensing chamber 185. This pressure monitoring and correction can occur almost continuously until the start of the dispensing segment. In this manner, the inside of the distribution chamber 185 can be maintained at a substantially desired reference pressure.

  As described above, the frequency at which the pressure sensor 112 can sample and report the pressure in the dispensing chamber 185 can be somewhat faster compared to the operating speed of the dispensing motor 200. To compensate for this difference, the pump controller 20 does not process the pressure measurement reported by the pressure sensor 112 during a particular time window that sends a signal to the dispensing motor 200 or causes the pressure sensor 112 to As a result, dispense motor 200 can complete its movement before another pressure measurement is received or processed by pressure sensor 112. Alternatively, the pump controller 20 detects that the dispense motor 200 has completed its movement before processing the pressure measurement reported by the pressure sensor 112 or until the pump controller 20 receives a notification. Can be made to wait.

  The beneficial effect of substantially maintaining the reference pressure using one embodiment of the closed loop control system as described above can be readily understood with reference to FIG. 10B, which is illustrated in FIG. FIG. 3 is a diagram illustrating an example of a pressure profile in a distribution chamber 185 when an embodiment of a control system is used. Correction for any pressure change caused by valve operation or another cause can be made at approximately point 4050, as described above with reference to FIGS. This pressure correction can correct the pressure in dispensing chamber 185 to near the reference pressure (represented by line 4040) required for dispensing at point 4060, at which point multistage pump 100 is ready. It is possible to enter a segment. After entering the preparation segment at approximately point 4060, one embodiment of a closed loop control system can compensate for any pressure drift in the preparation segment to substantially maintain the desired reference temperature. For example, at point 4070, the closed loop control system can detect a pressure increase and compensate for this pressure increase to substantially maintain the reference pressure 4040. Similarly, at points 4080, 4090, 4100, and 4110, the closed loop control system compensates for pressure drift in the dispensing chamber 185 to substantially maintain the desired reference pressure 4040 regardless of the length of the preparation segment. (Note: points 4080, 4090, 4100, and 4110 are only representative and other pressure corrections by the closed loop control system are shown in FIG. Is not described as such). As a result, during the preparation segment, the closed-loop control system keeps the distribution chamber 185 approximately at the desired reference pressure 4040 so that a more sufficient distribution can be achieved in subsequent distribution segments.

  However, to achieve this more sufficient distribution during subsequent distribution segments, when the distribution motor 200 is activated to distribute fluid from the distribution chamber 185, compensation for compensation is provided to substantially reduce the reference pressure. Sometimes it is desirable to keep it. More specifically, at a point 4060 immediately after the pressure correction occurs and the multistage pump 100 first enters the preparation segment, the dispensing stage diaphragm 190 may be in the initial state. In order to achieve the desired dispensing from this initial position, the dispensing stage diaphragm 190 must be moved to the dispensing position. However, as described above, after correcting for pressure drift, the dispensing stage diaphragm 190 may be in a second position that is different from the initial position. In some embodiments, this difference must be compensated for in the dispensing segment by moving the dispensing stage diaphragm 190 to the dispensing position to achieve the desired dispensing. In other words, to achieve the desired dispensing, after any pressure drift correction occurs in the dispensing segment, the dispensing stage diaphragm 190 is moved from its second position to the multi-stage pump 100 first into the preparation segment. It is possible to move to the initial position of the dispensing stage diaphragm 190 when it enters, and then to move the dispensing stage diaphragm 190 by the distance from the initial position to the dispensing position.

  In one embodiment, when the multi-stage pump 100 first enters the preparation segment, the pump controller 20 calculates the initial distance (distribution distance) and moves the distribution motor 200 to achieve the desired distribution. It is possible to make it. While the multi-stage pump 100 is in the preparation segment, the pump controller 20 may record the distance (corrected distance) that the dispensing motor 200 has moved to compensate for any pressure drift that occurred during the preparation segment. Is possible. During the dispensing phase, to achieve the desired dispensing, the pump controller 20 can send a signal to the dispensing motor 200 and move it by the correction distance plus (or minus) the dispensing distance. It is.

  However, in other cases, it may not be desirable to compensate for these pressure corrections when the dispensing motor 200 is activated to dispense fluid from the dispensing chamber 185. More specifically, at stage 4060, pressure correction occurs, and dispensing stage diaphragm 190 can be in the initial position immediately after multistage pump 100 first enters the preparation segment. In order to achieve the desired dispensing from this initial position, the dispensing stage diaphragm 190 must be moved by the dispensing distance. As described above, after correcting for pressure drift, the dispensing stage diaphragm 190 may be in a second position that is different from the initial position. In some embodiments, it is possible to achieve the desired dispensing by simply moving the dispensing stage diaphragm 190 by the dispensing distance (starting from the second position).

  In one embodiment, when the multi-stage pump 100 first enters the preparation segment, the pump controller 20 can calculate the initial distance and move the dispensing motor 200 to achieve the desired dispensing. It is. Then, during the dispensing phase, to achieve the desired dispensing, the pump controller 20 sends a signal to the dispensing motor 200 to the distance traveled by the dispensing motor 200 to compensate for pressure drift in the preparation segment. Regardless, it is possible to move this initial distance.

  Choosing one of the above-described embodiments to be used or applied to any given environment is such as a system, apparatus, or empirical conditions to be used with the selected embodiment, among others. It will be clear that it depends on a number of factors. Also, although the above-described control system embodiments to substantially maintain the reference pressure have been described with respect to compensating for the increase in pressure drift during the preparation segment, these same system and method embodiments have many. It will also be apparent that it is equally applicable to compensation for pressure drift rises or drops in the preparation segment of stage pump 100 or other segments. Furthermore, although embodiments of the present invention are described with respect to multi-stage pump 100, these inventions (eg, control methods, etc.) are equally good for single-stage or substantially other types of pump devices. It will be understood that the invention is applicable to and can be used in these devices.

  It would be useful to describe an example such as a single stage pumping device that can be used in connection with various embodiments of the present invention. FIG. 11 is a diagram illustrating one embodiment of a pump assembly for pump 4000. The pump 4000 can be similar to one of the multi-stage pumps 100 described above in the case of a dispensing stage and includes a rolling diaphragm pump driven by a stepper brushless DC motor or other motor. Can do. The pump 4000 can include a distribution block 4005 that defines various fluid flow paths through the pump 4000 and at least partially defines a pump chamber. The dispensing pump block 4005 may be an integral block of PTFE, modified PTFE, or other material, according to one embodiment. Because these materials do not react or only minimally react with other process fluids, by using these materials, the flow path and pump chamber, together with minimal additional hardware, is distributed block 4005. Can be machined directly in. Accordingly, distribution block 4005 reduces the need for piping by providing an integral fluid manifold.

The distribution block 4005 has various external inlets and outlets including, for example, an inlet 4010 that receives fluid, a vent / purge outlet 4015 for purge / vent fluid, and a distribution outlet 4020 through which fluid is distributed into the distribution segment. Can be included. In the example of FIG. 11, the distribution block 4005 includes an external purge outlet 4010 so that the pump has only one chamber. US Provisional Patent Application No. 60 / 741,667 by Iraj Gashgaee, “O-Ring-Less Low Profile Fittings and Fitting Assembly Theof” (filed December 2, 2005), and U.S. provisional application by Iraj Gashgae 11 / 602,513 , entitled “O-Ring-Less Low Profile Fittings and Assemblies” (filed on Nov. 20, 2006 ), used to connect the external inlet and outlet of distribution block 4005 to the fluid line One embodiment of a possible pipe fitting is disclosed, which is incorporated herein by reference in its entirety.

  The distribution block 4005 is from the inlet to the inlet valve (eg, defined at least in part by the valve plate 4030), from the inlet valve to the pump chamber, from the pump chamber to the vent / purge valve, and from the pump chamber to the outlet 4020. Send fluid. The pump cover 4225 can prevent damage to the pump motor, and the piston housing 4027 can provide protection for the piston and is formed of polyethylene or other polymer according to one embodiment of the invention. be able to. The valve plate 4030 provides a valve housing for a system of valves (eg, inlet valves and purge / vent valves) that can be configured to direct fluid flow to the various components of the pump 4000. The valve plate 4030 and corresponding valves can be formed in a manner similar to that described in connection with the valve plate 230 described above. According to one embodiment, each of the inlet valve and the purge / vent valve is at least partially integrated into the valve plate 4030 and is opened or closed by applying pressure or vacuum to the corresponding diaphragm. It is a valve. In other embodiments, some valves can be external to the distribution block 4005 or placed in additional valve plates. According to one embodiment, a sheet of PTFE is sandwiched between the valve plate 4030 and the distribution block 4005 to form various valve diaphragms. The valve plate 4030 includes a valve control inlet (not shown) at each valve to apply pressure or vacuum to the corresponding diaphragm.

  Similar to multi-stage pump 100, pump 4000 includes several functions to prevent fluid drops from entering the area of multi-stage pump 100 that houses the electronics. The “drip-proof” function can include a protruding lip, a tilt function, a seal between components, a metal / polymer interface, and other functions described above to separate the electronics from the drop. The electronics and manifold can be configured in the same manner as described above to reduce thermal effects on the fluid in the pump chamber. Thus, similar functions, such as those used in multi-stage pumps, to reduce form factor and thermal effects and prevent fluids from entering the electronics housing can be used for single-stage pumps.

  In addition, many of the control methods described above can be used with the pump 4000 to provide a substantially sufficient distribution. For example, by controlling the valve of pump 4000 using an embodiment of the present invention, the time during which the fluid path through the pump device is closed (eg, relative to the outside of the pump device) is substantially minimized. It is possible to ensure the operation of the valve system of the pump device based on a valve sequence that is configured to be suppressed. Further, in certain embodiments, a sufficient amount of time is used during valve 4000 operation to change the state of the valve so that the particular valve is fully opened or closed before another change is disclosed. It can be so. For example, the operation of the motor of pump 4000 can be delayed for a sufficient amount of time so that the inlet valve of pump 4000 can be fully opened before the filling phase.

  Similarly, embodiments of the system and method for compensating for pressure drift that may occur in the chamber of the pump apparatus can apply substantially equal effectiveness to the pump 4000. Based on the pressure detected in the distribution chamber, the distribution motor can be controlled to keep the distribution chamber approximately at the reference pressure prior to distribution. The control loop repeatedly determines whether the pressure in the dispensing chamber is different from the desired pressure (eg, high or low), and in such cases, adjusts the operation of the pump means to approximately achieve the desired pressure in the dispensing chamber. It is possible to use it so that it may be kept at the

  Adjustment of the pressure in the chamber of the pump 4000 can occur at virtually any time, but can be particularly useful before the dispensing segment is started. More specifically, when the pump 4000 first enters the preparation segment, the pressure in the dispensing chamber 185 is the desired pressure for subsequent dispensing segments (eg, the dispensing pressure measured from calibration or previous dispensing) or its The reference pressure that is a fraction can be approximated. With this desired dispensing pressure, it is possible to achieve a dispensing having the desired set of properties, such as the desired flow rate, flow rate, etc. By directing the fluid in the dispensing chamber 185 to the desired reference pressure at any time before the outlet valve opens, the followability and variability of the components of the pump 4000 are adequately compensated before the dispensing segment. Distribution can be achieved.

  However, since there is some delay between entering the preparation segment and the start of the dispensing segment, the pressure in the pump 4000 chamber may vary during the dispensing segment based on various factors. In order to prevent this pressure drift, embodiments of the present invention can be used so that the interior of the pump 4000 chamber is substantially held at the desired reference pressure and sufficient distribution is achieved in subsequent distribution segments. is there.

  In addition to controlling pressure drift within a single stage pump, embodiments of the present invention may be used to distribute chambers resulting from the operation of various mechanisms or components within the pump 4000 or devices used with the pump 4000. It is also possible to compensate for pressure fluctuations.

  One embodiment of the present invention is able to compensate for pressure changes in the pump chamber caused by closure of the purge or vent valve prior to the start of the dispensing segment (or other segment). This compensation is substantially the same as that described above with respect to multi-stage pump 100, when the purge or inlet valve is closed, the chamber capacity of pump 4000 increases substantially by the hold-up capacity of that valve. Thus, it is achieved by rotating the motor of the pump 4000 in the reverse direction.

  Accordingly, embodiments of the present invention provide a pumping device that is characterized by gentle fluid handling. By sequencing the opening and closing of the valves in the pumping device and / or the operation of the motor, possibly damaging pressure spikes can be avoided or reduced. Embodiments of the present invention can also use other pump control mechanisms and valve timing adjustments to help reduce the adverse effects of pressure on the process fluid.

  In the foregoing specification, the invention has been described with reference to specific embodiments. It will be appreciated by those skilled in the art that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and drawings are to be regarded in an illustrative rather than restrictive sense, and all such modifications are intended to be included within the scope of the present invention. .

  Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. It should be noted that benefits, advantages, solutions to problems, and any components that may give rise to, or become more obvious, any benefit, advantage, or solution are important or necessary for any or all of the claims, Or should not be construed as an essential function or component.

FIG. 1 is a diagram showing an embodiment of a pump system. FIG. 2 is a diagram illustrating a multi-stage pump (“multi-stage pump”), according to one embodiment of the present invention. 3A, 3B, 4A, 4C, and 4D show various embodiments of a multi-stage pump. 3A, 3B, 4A, 4C, and 4D show various embodiments of a multi-stage pump. 3A, 3B, 4A, 4C, and 4D show various embodiments of a multi-stage pump. It is the figure which showed one Embodiment of the distribution block. 3A, 3B, 4A, 4C, and 4D show various embodiments of a multi-stage pump. 3A, 3B, 4A, 4C, and 4D show various embodiments of a multi-stage pump. FIG. 5 illustrates valve and motor timing for one embodiment of the present invention. FIG. 6 is a diagram of an example pressure profile for an embodiment of an actuation sequence used by the pump. FIG. 7 is an illustration of an example of a partial pressure profile of one embodiment of an actuation sequence used by the pump. 8A and 8B show one embodiment of valve and motor timing for various segments of pump operation. 8A and 8B show one embodiment of valve and motor timing for various segments of pump operation. 9A and 9B are diagrams illustrating one embodiment of valve and motor timing for various segments of pump operation. 9A and 9B are diagrams illustrating one embodiment of valve and motor timing for various segments of pump operation. 10A and 10B are diagrams of an example of a pressure profile that is part of one embodiment of the actuation sequence used by the pump. 10A and 10B are diagrams of an example of a pressure profile that is part of one embodiment of the actuation sequence used by the pump. FIG. 11 is a diagram showing an embodiment of a pump system.

Claims (18)

Introducing a fluid into the distribution chamber of the pump device;
Moving the diaphragm of the pump means of the pump device to adjust the volume of the distribution chamber to compensate for pressure fluctuations from a reference pressure in the distribution chamber, the diaphragm comprising a motor Method that is moved directly using.   The method of claim 1, wherein the pressure fluctuation is a pressure drop due to valve opening or valve closing.   The pressure variation is approximately proportional to the hold-up volume of the valve, and the diaphragm is moved to increase the volume of the dispensing chamber by an amount substantially equal to the hold-up volume of the valve. The method described in 1.   4. The diaphragm of claim 3, wherein the diaphragm is moved to increase the volume of the distribution chamber by approximately an overshoot volume and then moved to decrease the volume of the distribution chamber by approximately the overshoot volume. Method.   4. The method of claim 3, wherein the diaphragm is moved to increase the volume of the distribution chamber until a desired pressure is achieved in the distribution chamber.   The diaphragm is moved to increase the volume of the distribution chamber until a pressure lower than the desired pressure is achieved in the distribution chamber, and then approximately in the distribution chamber until the desired pressure is achieved. 4. The method of claim 3, wherein the method is moved to reduce volume. Introducing fluid into the distribution chamber of the pump device;
Computer readable including translatable instructions for moving the diaphragm of the pumping means of the pumping device to adjust the volume of the dispensing chamber to compensate for pressure variations from a reference pressure in the dispensing chamber A medium,
The diaphragm is a computer readable medium that is moved directly using a motor.   The computer readable medium of claim 7, wherein the pressure fluctuation is a pressure drop due to valve opening or valve closing.   The pressure rise is approximately proportional to the hold-up volume of the valve, and the diaphragm is moved to increase the volume of the dispensing chamber by an amount substantially equal to the hold-up volume of the valve. The computer-readable medium according to claim 8.   The computer of claim 9, wherein the diaphragm is moved to increase the volume of the distribution chamber by approximately an overshoot volume and then moved to decrease the volume of the distribution chamber by approximately the overshoot volume. A readable medium.   The computer readable medium of claim 9, wherein the diaphragm is moved to increase the volume of the distribution chamber until a desired pressure is achieved in the distribution chamber.   The diaphragm is moved to increase the volume of the distribution chamber until a pressure lower than the desired pressure is achieved in the distribution chamber, and then approximately in the distribution chamber until the desired pressure is achieved. The computer-readable medium of claim 9, wherein the computer-readable medium is moved to reduce capacity. A pumping device comprising a supply chamber, a dispensing chamber operable to receive a fluid for dispensing, and a pump means in the dispensing chamber, the pumping means operable to directly operate the diaphragm A pump device comprising a diaphragm coupled to a simple motor;
A controller configured to adjust movement of the pump means of the pump device to adjust the volume of the distribution chamber to compensate for pressure fluctuations from a reference pressure in the distribution chamber. .   The system of claim 13, wherein the pressure fluctuation is a pressure drop due to valve opening or valve closing.   The pressure variation is approximately proportional to the hold-up volume of the valve, and adjusting the volume of the distribution chamber increases the volume of the distribution chamber by an amount approximately equal to the hold-up volume of the valve. The system of claim 14, comprising moving the diaphragm.   Adjusting the volume of the distribution chamber moves the diaphragm to increase the volume of the distribution chamber by approximately the overshoot volume, and then moves to decrease the volume of the distribution chamber by approximately the overshoot volume. 16. The system of claim 15, comprising:   16. The system of claim 15, wherein adjusting the volume of the distribution chamber includes moving the diaphragm to increase the volume of the chamber until a desired pressure is achieved in the distribution chamber.   Adjusting the volume of the distribution chamber moves the diaphragm to increase the volume of the distribution chamber until a pressure lower than the desired pressure is achieved in the distribution chamber, and then approximately the desired pressure The system of claim 15, comprising moving the diaphragm to reduce the volume of the dispensing chamber until is achieved.

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