JP4045325B2 - Apparatus and method for reducing power consumption of oil diffusion pump - Google Patents

Description

  The present invention relates to means and apparatus for reducing the power consumption of an oil diffusion pump.

In general, the oil diffusion pump is configured as shown in FIG. 5, and the oil 4 heated by the heater 5 is vaporized and blown from the jet 3 to the inner wall surface of the oil diffusion pump main body 1. The air is blown off in the traveling direction of the jet and exhausted from the exhaust port 8.
Since the outer wall surface of the oil diffusion pump main body 1 is cooled by the water cooling pipe 2, the oil 4 adhering to the inner wall is condensed and returned to the lower side of the oil diffusion pump main body 1, reheated, vaporized again, and circulated.

  The heater 5 is wired from the primary power source via the breaker 7 and the electromagnetic switch 6, and the heater is supplied with electric power necessary to obtain a desired exhaust performance. In general, the heater voltage and the heater current are constant and the maximum power. However, as disclosed in, for example, Patent Documents 1 to 3, the oil temperature is monitored by a thermocouple and the heater is detected by this signal. There is also a method of adjusting the output power.

  Patent Document 1 provides a terminal for measuring the working fluid temperature and a terminal for measuring the nozzle temperature, and controls the power supplied to the heater based on the detection signal, thereby accurately determining the pump start time and stop time. Management prevents wasteful power consumption and enhances pump performance.

  In Patent Document 2, the power supplied to the heater during operation is controlled by a constant temperature control method, and the power supplied is always maintained at a predetermined minimum power or higher so that oil contamination does not occur even when a disturbance occurs. Is to control.

Patent Document 3 obtains in advance the data regarding the ultimate pressure value in the chamber and the operation time for reaching the ultimate pressure value corresponding to the oil temperature of the hydraulic oil as a plurality of data for a plurality of corresponding oil temperatures. The energy consumption is efficiently suppressed by operating the hydraulic oil temperature corresponding to the matching data by obtaining the matching data from a plurality of data corresponding to the target vacuum degree and arrival time condition. .
JP 62-23600 JP-A-9-88899 JP 2003-97500 A

  There is a proportional relationship between the heater power and the critical back pressure and maximum displacement of the oil diffusion pump. The higher the heater power, the higher the critical back pressure and the larger the maximum displacement, but the exhaust speed and ultimate pressure are not necessarily proportional to the heater power. It cannot be said that it is a relationship, and tends to depend on the shape of the jet 3 and the like. Therefore, it is desirable to lower the heater power when the performance of the auxiliary pump is high and the gas flow rate introduced when the oil diffusion pump is used is significantly smaller than the maximum displacement of the oil diffusion pump. However, since the oil diffusion pump is designed so that it can be installed in various devices, some devices require an unnecessarily large amount of power. Here, the auxiliary pump is a vacuum pump for maintaining the back pressure of the oil diffusion pump below a critical value, and is also used as a roughing pump.

  In addition, as disclosed in Patent Documents 1 to 3, there is a problem that the optimum oil temperature cannot be uniquely determined by the method in which the heater is equipped with a temperature regulator and the supplied power is controlled. This is because the measurement temperature varies depending on the oil temperature measurement position, and is due to the fact that it is difficult to measure the exact oil temperature. Furthermore, individual differences in the oil diffusion pump jet 3 and changes over time, or oil 4 usage time and changes over time can cause individual differences of up to ± 5 ° C. Even in the case of an apparatus, it is necessary to individually set the temperature, and it has been difficult to mass sell an apparatus for reducing power consumption by adjusting the temperature.

  In addition, since the oil temperature tends to decrease as the deterioration of the oil 4 progresses, there is a problem that the power consumption increases as the deterioration of the oil 4 progresses. Deteriorated hydraulic oil needs to be replaced, but the method of monitoring the oil temperature and controlling the power supply does not notice the deterioration and increases the power supply to maintain the oil temperature, so miss the time to replace the hydraulic oil Not only will unnecessary power be wasted. If not only the oil temperature but also the supplied power is monitored during the operation of the oil diffusion pump, it is possible to appropriately determine the timing of replacing the hydraulic oil, but a separate instrument for constantly monitoring the supplied power is required.

  Currently, environmental problems are tight in all fields and energy saving is required. As described above, the conventional oil diffusion pump is designed to be mounted on various devices, and a large amount of electric power has been input. As described above, there is a problem in that the amount of electric power may be excessive depending on the vacuum device to be mounted.

  An object of the present invention is to solve the above-described problems of the conventional apparatus, and to provide an apparatus that can achieve the required power amount and exhaust performance most suitable for various apparatuses.

  In view of the problem that the amount of input power in the conventional oil diffusion pump is excessive depending on the mounted vacuum device, the present invention reduces the input power to the oil diffusion pump while considering the exhaust performance of the oil diffusion pump. By cutting off intermittently and reducing the amount of power consumption for the cut-off time, the balance between the performance in terms of power consumption and the exhaust performance is intended to be improved.

  According to a first aspect of the present invention, in an oil diffusion pump that exhausts a suction gas by ejecting a steam flow of hydraulic oil heated by a heater from a jet, electric power supplied to the heater is based on a control signal input in advance. It is a power consumption reduction device for an oil diffusion pump that cuts off intermittently. The power consumption reduction device is composed of a power regulator connected to the heater and a timer connected to the power regulator, so that intermittent power is periodically supplied to the heater based on the ON / OFF ratio transmitted by the timer. I made it.

  In the first aspect, the ON / OFF ratio input to the timer is set based on previously measured data. Here, the actually measured data includes at least data related to the exhaust performance of the oil diffusion pump. The timer is set so that the ON / OFF ratio is minimized so that the oil diffusion pump does not interfere with use, that is, the exhaust performance satisfies a predetermined value. The exhaust performance of the oil diffusion pump was at least one of the critical back pressure, maximum displacement, exhaust speed, and ultimate pressure of the oil diffusion pump. Here, the ON / OFF ratio immediately before the oil temperature of the oil diffusion pump decreases is set in the timer. Furthermore, the oil diffusion pump may be equipped with a heat insulating means, and an ON / OFF ratio that reduces the amount of input power for the oil temperature raised by the heat insulating means may be set in the timer.

  The second aspect of the present invention is an oil diffusion pump that exhausts intake gas by injecting a steam flow of hydraulic oil heated by a heater from a jet, and the input power to the heater is input at a signal ratio input in advance. It is an oil diffusion pump provided with the control apparatus which controls ON / OFF.

  The third aspect of the present invention is a method for reducing power consumption used in an oil diffusion pump that exhausts intake gas by injecting a vapor flow of hydraulic oil heated by a heater from a jet, and turning on the electric power supplied to the heater Determining the minimum ON / OFF ratio at which the exhaust performance of the oil diffusion pump satisfies a predetermined value, and the heater periodically with the minimum ON / OFF ratio. This is a method for reducing the amount of power consumed by the oil diffusion pump, comprising the step of supplying intermittent power to the oil diffusion pump.

  By intermittently cutting off the electric power input to the oil diffusion pump in the present invention, it becomes possible to efficiently reduce the power consumption of the oil diffusion pump. Moreover, the power consumption of the existing oil diffusion pump can be significantly reduced only by mounting the power regulator and timer of the present invention as a unit.

  Embodiments of the present invention will be described below with reference to the drawings. The same parts as those in FIG. In FIG. 1, 9 is a power regulator and 10 is a timer. The input power is sent to the heater 5 via the power regulator 9. The timer 10 transmits a pre-input ON / OFF ratio and ON / OFF cycle to the power regulator 9, and the power regulator 9 intermittently supplies power to the heater 5 based on a signal generated by the timer 10. Supply. The ON / OFF ratio and ON / OFF cycle input to the timer may be set freely, and the power regulator 9 supplies power to the heater in the ON signal and cuts off power supplied to the heater in the OFF signal. . Although not shown, a detector for measuring the exhaust performance and an oil 4 in the vicinity of the oil 4 are provided as necessary in order to acquire data for determining the ON / OFF ratio to be input in advance. Both or one of the detectors for measuring the temperature are provided.

  In the embodiment, energy saving is achieved by mounting the timer 10 and the power regulator 9 in the oil diffusion pump, but the power consumption reduction means of the present invention intermittently cuts off the energy input to the oil diffusion pump. It is not limited to this as long as it does. For example, instead of the power regulator 9, the electromagnetic switch 6 may be turned on / off using a timer, a relay, or the like. However, in that case, the contact life of the electromagnetic switch 6 and the noise during operation are sufficient. It is necessary to consider. Moreover, energy saving of the existing oil diffusion pump can be achieved only by unitizing and mounting the timer 10 and the power regulator 9.

  By supplying intermittent energy to the oil diffusion pump, it is possible to cut wasteful power that has been excessively applied, and to promote an energy saving effect. This is because the oil temperature does not drop suddenly even if the energy input to the hydraulic oil is cut off. By supplying energy for a certain time again immediately before the temperature decreases. This makes it possible to maintain a constant temperature while intermittently omitting the input of energy.

  What is necessary is just to determine suitably the time and space | interval which interrupts | blocks input energy according to the objective from the balance of an energy saving effect and exhaust performance.

Hereinafter, a specific embodiment in the case of trying to obtain an energy saving effect using the timer 10 and the power regulator 9 shown in FIG. 1 will be exemplified.
In the first embodiment, the ON / OFF ratio and the ON / OFF cycle immediately before the oil temperature of the oil diffusion pump is lowered are detected and set in the timer 10.

  The ON / OFF ratio and ON / OFF cycle set in the timer 10 are obtained from experimental data according to the flowchart of FIG. First, the oil temperature t1 at the time of continuously supplying constant electric power to the conventional oil diffusion pump is measured. Further, an oil temperature t2 at which it is determined that the temperature has decreased is set in advance. The temperature unit for determining that the oil temperature has decreased need not be a unit of 1 ° C. or a sufficient unit of 1 ° C., and a decrease of 1 to 3 ° C. may be determined as a decrease in oil temperature. However, it is desirable to appropriately determine this temperature unit as necessary.

  Next, the timer 10 and the power regulator 9 of FIG. 1 are connected, the ON time is shortened, and the amount of time is set as the OFF time. By gradually shortening the ON time, the ON / OFF ratio is changed to reduce the input power amount, and the oil temperature tn is measured and compared with t2 at each stage. At this time, it is obvious that if the ON time is significantly shortened, that is, if the OFF time is lengthened, the exhaust performance of the oil diffusion pump significantly decreases. Is desirable and efficient. In the flowchart shown in the figure, the OFF time is increased by 1%, but the ratio may be appropriately selected. Further, the ON / OFF cycle does not need to be in units of hundredths of seconds or sufficient units of one second, but may be in units of several seconds or tens of seconds. It is preferable that the cycle is not too short in consideration of the delay of the input power at the time of startup. However, since it is necessary to set the time unit so that the oil temperature does not fluctuate by increasing the time unit, it is desirable to adjust it appropriately.

  When the ON time is shortened, that is, when the OFF time is lengthened, the ON / OFF ratio at which the measured temperature tn is lower than the oil temperature t2 at which it is determined that the temperature has decreased is reached. Since the oil temperature is decreasing at this time ratio, it can be considered as a branch point where the exhaust performance starts to have a noticeable effect, so it is efficient to consider the time ratio before this stage as the optimum. . In the flowchart of the figure, if the measured temperature tm when the measured oil temperature tn is equal to or lower than t2, the ON / OFF ratio at that time is measured, and if the measured oil temperature tm is smaller than t2, the measurement is performed one step before. The calculated ON / OFF ratio is obtained.

  If the ON / OFF ratio immediately before the oil temperature decreases as described above is obtained, the critical back pressure and the maximum displacement at this ON / OFF ratio are measured by experiment. Measurement of the critical back pressure and maximum displacement is serious because it causes a back flow of oil to the exhausted system when using the oil diffusion pump. It is desirable to understand the situation and take a margin.

  Compare the critical back pressure and maximum displacement with the situation when using a normal oil diffusion pump, and if there is no problem in use, measure the exhaust speed and ultimate pressure. In general, the exhaust speed and the ultimate pressure are not closely related to the input power, and if the oil temperature decreases by about 1 to 3 ° C., it is difficult to think of a significant decrease in performance, but it is desirable to confirm that there is no problem in use.

If the exhaust performance such as critical back pressure, maximum displacement, exhaust speed, and ultimate pressure is not a problem in use, the OFF time of the power input to the heater 5 at this time is divided by the sum of the ON time and the OFF time. , 100 can be considered as the power consumption reduction rate.
If there are problems in use in exhaust performance such as critical back pressure, maximum displacement, exhaust speed, ultimate pressure, etc. in the ON / OFF ratio immediately before the oil temperature decreases, the ON / OFF of the previous stage is further The exhaust performance is measured by the ratio, and the optimum ON / OFF ratio may be obtained.

  Further, when the heater 5 is ON / OFF controlled, if the lower part of the oil diffusion pump main body 1 is covered with a heat insulating material as shown in FIG. Since heat can be cut off, an improvement in power consumption reduction effect can be expected.

In the second embodiment, an ON / OFF ratio and an ON / OFF cycle for reducing the input power amount to such an extent that the exhaust performance of the oil diffusion pump does not hinder the use are detected and set in the timer 10.
The ON / OFF ratio and ON / OFF cycle set in the timer 10 are acquired from experimental data according to the flowchart of FIG. By gradually increasing the OFF time, measuring the required exhaust performance such as critical back pressure, maximum displacement, exhaust speed, ultimate pressure, etc., and setting the timer 10 to the ON / OFF ratio immediately before the exhaust performance is affected The energy saving effect is increased. In the flowchart of FIG. 2, the OFF time is increased by 1% as in FIG. 2, but the ratio may be appropriately selected. The ON / OFF cycle may be selected as appropriate.

  In the third embodiment, a heat insulating means is mounted on the oil diffusion pump, and the ON / OFF ratio and the ON / OFF cycle for reducing the input electric energy for the temperature rise of the hydraulic oil by the heat insulating means are detected and set in the timer 10 To do. For example, when the heat insulating material 11 shown in FIG. 1 is covered at the lower part of the oil diffusion pump main body 1, heat leaking to the outside can be cut off, so that even when the input power is the same, the hydraulic oil is higher than when no heat insulating material is used. Temperature is maintained. If the hydraulic oil temperature obtained without using heat insulation is the hydraulic oil temperature that can be normally obtained, the excess amount of the heated oil energy is input, so the excessive amount of power is intermittently supplied. Reduce by cutting off power.

  The ON / OFF ratio and ON / OFF cycle set in the timer 10 are obtained from experimental data according to the flowchart of FIG. First, the oil temperature t1 when a constant constant power is supplied without using the heat insulation means and the oil temperature t3 when the constant constant power is supplied using the heat insulation means are measured. Next, the oil temperature tn is measured by gradually increasing the OFF time of the timer 10 and compared with t1. In the flowchart of FIG. 2, the OFF time is increased by 1% as in FIG. 2, but the ratio may be appropriately selected. The ON / OFF cycle may be selected as appropriate. This operation is repeated until the measured oil temperature becomes t1 or less. If the measured oil temperature tm at this time is equal to t1, the ON / OFF ratio at that time is determined. If the measured oil temperature tm is smaller than t1, one step before The ON / OFF ratio measured in the above may be set in the timer 10. Since the ON / OFF ratio set by the above means only reduces the amount of electric power for excessive input, it is not necessary to check the exhaust performance, but the exhaust performance may be confirmed just in case.

Next, the power regulator 9 and timer 10 shown in FIG. 1 are unitized and installed in an existing oil diffusion pump that continuously inputs the maximum power of the heater, and the result of actual power saving of the oil diffusion pump is illustrated. To do.
First, the ON / OFF ratio immediately before the oil temperature decreased was detected according to the flowchart shown in FIG. The oil temperature t1 when operating in the same manner as before without installing the power saving unit is 249 ° C. As a result of setting the oil temperature t2 to determine that the temperature has decreased to 247 ° C and the ON / OFF cycle to 50 seconds, 4: 1 was detected as the ON / OFF ratio immediately before the temperature decreased. FIG. 11 shows the measurement result of the oil temperature. Hereinafter, the operation data of an existing oil diffusion pump not equipped with a power saving unit is assumed to be standard time data. The standard with jacket is the operation data when the heat insulating material shown in 11 of FIG. 1 is used for the oil diffusion pump shown in FIG. 5. Since the oil temperature higher than the standard time is maintained, the third embodiment is used. Thus, the input power amount for the temperature rise may be reduced.

Next, the exhaust performance at an ON / OFF ratio of 4: 1 and an ON / OFF cycle of 50 seconds was measured and compared with the exhaust performance at the standard time. The results are shown in FIGS.
FIG. 6 shows the exhaust velocity, FIG. 7 shows the maximum displacement, and FIG. 8 shows the ultimate pressure and critical back pressure. From the figure, it can be seen that the exhaust speed, the maximum displacement, and the ultimate pressure when using the power saving unit are almost equal to the standard time, but only the critical back pressure is lower than the standard time. However, the critical back pressure of the oil diffusion pump should generally be 13 Pa or higher, and the ultimate pressure of the auxiliary pump connected to the oil diffusion pump is much lower than 13 Pa, so it is measured as the critical back pressure when using the power saving unit. 25.3 Pa is a value which has no problem at all. Therefore, there is no problem in the exhaust performance, and the timer 10 may be used with an ON / OFF ratio of 4: 1 and an ON / OFF cycle of 50 seconds.

  FIG. 9 shows the time change of the oil temperature, and is a result of comparing the rise at the standard time and when using the power saving unit. Compared to the standard time, there was a slight delay in starting up when using the power-saving unit. Although there is no problem in using the actual oil diffusion pump, if you want to speed up the start-up, the maximum power of the heater is continuously supplied without using the ON / OFF control until the oil temperature reaches the specified level after the start of operation. do it.

  FIG. 10 shows the time change of the oil temperature when the ON / OFF ratio is changed with the same ON / OFF ratio. The ON / OFF ratio was set to 4: 1. From the figure, it can be seen that a higher oil temperature is maintained when the ON / OFF cycle is 50 seconds than when the ON / OFF cycle is 10 seconds. Since this is considered to be caused by the delay of the input power at the time of rising as described above, it is desirable to select the ON / OFF cycle from the actually measured data.

  From the above, by supplying intermittent power with an ON / OFF ratio of 4: 1 and an ON / OFF cycle of 50 seconds, it has become possible to reduce power consumption by 20% while maintaining the exhaust performance of the existing oil diffusion pump. .

  By providing the oil diffusion pump with the timer 10 and the power adjuster 9 according to the present invention, it is possible to adjust the optimum power input amount to the heater 5. Thereby, the power consumption can be reduced as much as possible and energy saving can be achieved by making the performance optimal for the performance of the auxiliary pump of the vacuum device to which the oil diffusion pump is attached and the exhaust performance in use.

  In heater control using a temperature regulator, the reliability of the measured oil temperature is not high, or the oil temperature changes over time. In some cases, the exhaust performance may be hindered. However, the present invention does not feed back the change in oil temperature over time to the power control. It is possible to obtain. Further, since it is not necessary to feed back the temperature measurement result by a thermocouple or the like arranged in the pump, it contributes to simplification and cost reduction of the apparatus. Furthermore, since the replacement timing of the hydraulic oil can be determined appropriately, there is no problem of increasing the power consumption and maintaining the oil temperature without noticing the deterioration of the hydraulic oil as seen in the conventional temperature adjustment control. In addition, since the embodiment measures the difference in the oil temperature, the measurement error due to the measurement position of the hydraulic oil temperature can be ignored.

  In the conventional method for setting the oil temperature, it was necessary to individually set an appropriate oil temperature even for the vacuum device of the same type and the same application. Since it is possible to operate with the same ON / OFF time ratio uniquely, it is easy to unitize the timer 9 and the power regulator 10 that are optimally set in advance and sell them as a single unit.

  Further, in the above embodiment, the operation is performed by controlling the ON / OFF ratio and its cycle. However, for example, a configuration in which only the OFF width is controlled with the ON width being constant may be used. It is good also as a structure which controls only ON width | variety by making constant. Further, some of the controls described above may be combined.

The figure which shows the oil diffusion pump of this invention Flowchart of the first embodiment of the present invention Flowchart of the second embodiment of the present invention Flowchart of the third embodiment of the present invention Diagram showing a conventional oil diffusion pump Diagram showing comparison of exhaust speed between standard time and power saving unit Diagram showing maximum displacement comparison between standard time and power saving unit Figure showing comparison of ultimate pressure and critical back pressure when using standard and power-saving units Diagram showing rise comparison between standard time and power saving unit Diagram showing ON / OFF cycle comparison Diagram showing oil temperature

Explanation of symbols

1 Oil diffusion pump body
2 Water cooling pipe
3 Jet
4 oil
5 Heater
6 Electromagnetic switch
7 Breaker
8 Discharge port
9 Power regulator
10 timer
11 Insulation

Claims (7)

Oil diffusion that intermittently cuts off the electric power supplied to the heater based on pre-input control data in an oil diffusion pump that exhausts the suction gas by injecting a vapor flow of hydraulic oil heated by the heater from a jet A power consumption reduction device for a pump,
A power regulator connected to the heater, and a timer connected to the power regulator,
The timer is set to turn on / off the power regulator according to the pre-input control data,
An ON / OFF ratio and a cycle time set in the timer are set based on data measured in advance, and an apparatus for reducing power consumption of an oil diffusion pump.
2. The power consumption reduction device according to claim 1, wherein the previously measured data represents a relationship between at least the ON / OFF ratio and cycle time and the exhaust performance of the oil diffusion pump. Quantity reduction device.
2. The power consumption reduction device according to claim 1, wherein the previously measured data is a minimum in which at least one of critical back pressure, maximum exhaust amount, exhaust speed, and ultimate pressure, which are exhaust performance of the oil diffusion pump, satisfies a predetermined value. An oil diffusion pump power consumption reduction device characterized by expressing the ON / OFF ratio of the oil diffusion pump.
The power consumption reduction device according to any one of claims 1 to 3 , wherein the previously measured data represents an ON / OFF ratio immediately before the oil temperature of the oil diffusion pump decreases. To reduce power consumption.
The power consumption reduction device according to claim 1,
Insulating means mounted on the oil diffusion pump is provided, and the previously measured data represents an ON / OFF ratio for reducing the input power amount of the oil temperature raised by the insulating means. Power consumption reduction device.
An oil diffusion pump that exhausts a suction gas by injecting a steam flow of heated hydraulic oil from a jet,
The oil diffusion pump provided with the heater which heats this hydraulic fluid, and the power consumption reduction apparatus as described in any one of Claim 1 to 5 connected to the electric power feeding line of this heater.
A method for reducing power consumption used in an oil diffusion pump that exhausts a suction gas by injecting a vapor flow of hydraulic oil heated by a heater from a jet,
Deriving the minimum ON / OFF ratio at which the exhaust performance of the oil diffusion pump satisfies a predetermined value with respect to the relationship between the ON / OFF ratio and cycle time of the electric power supplied to the heater and the exhaust performance of the oil diffusion pump; And a method for reducing the amount of power consumption, comprising the step of periodically supplying intermittent power to the heater at the minimum ON / OFF ratio.

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