RU2029447C1 - Coordinate table - Google Patents

Abstract

FIELD: mechanical engineering. SUBSTANCE: coordinate table is provided with hydrostatic guides of cylindrical shape, each of them being fitted with two hydrostatic supports placed at base distance from each other. Each support incorporates two high-pressure chambers placed in vertical plane and two high-pressure chambers positioned in horizontal plane. Each chamber is hydraulic joined to pump station through magneto-rheological choke. Low-pressure chambers are placed around each high-pressure chamber. For increase of positioning precision, reliability and speed of action hydrostatic guides of cylindrical shape are sealed by means of tightening elements made in the form of flexible thin-walled shells in the form of bodies of revolution mounted for rolling between hydrostatic guide of cylindrical shape and corresponding carriage. Magneto-rheological chokes are manufactured in the form of magnetic field inductor. EFFECT: increased positioning precision, reliability and speed of action. 8 cl, 18 dwg

Description

 The invention relates to mechanical engineering and can be used, for example, in installations of ionic, electronic, X-ray and photolithography, in the construction of various microscopes, coordinate measuring machines.

 Known coordinate table for moving products in the space of a coordinate measuring machine, containing hydrostatic guides sealed at the ends with sealing elements of a cuff type, a drive, a drive control device made in the form of electro-hydraulic converters, a device for measuring the position of the coordinate table.

A disadvantage of the known table is the long time for its precise positioning due to the fact that electro-hydraulic converters that control the flow of working fluid contain movable, inertial elements. Due to the presence of a relatively rough one-stage positioning system, only the drives of the coordinate table, the accuracy of its positioning is low. The presence of large friction forces in the guides, for example, in cuff-type sealing elements, leads to the same result. Due to the presence of significant friction forces, the working surfaces of the table elements are destroyed, which leads to clogging of wear products of both the guides and the throttling channels of the electro-hydraulic drive control device. As a consequence of this - their failure (jamming) and a decrease in the reliability of the coordinate table as a whole. The presence in the design of the coordinate table of widely known hydrostatic guides operating on mineral oils does not allow for continuous adjustment of the product in the automatic mode or constant stabilization of its position in space along six spatial coordinates in the process of its operation - X, Y, Z, α _x , α _y , α _z . In addition, when setting up the coordinate table, it is necessary to set the parallelism of the guides with high accuracy, to establish and maintain constant flow of the working fluid through their manual type flow controllers, and during the operation of the coordinate table, their additional periodic adjustment is required, which is very laborious and inconvenient.

 The closest technical solution to the invention adopted as a prototype is a precision coordinate table device containing a fixed base on which a lower carriage is mounted on two hydrostatic guides sealed with sliding cuff-type sealing elements and welded metal bellows and equipped with manual hydraulic inlet chokes, the upper carriage mounted on the lower carriage with the ability to move on two similar hydrostatic x guides in the direction perpendicular to the direction of movement of the lower carriage drive in the form of two hydraulic cylinders, causing the carriage, drive the electrohydraulic type of control device, two-coordinate measuring device, position coordinate table, the pumping station, is hydraulically connected with a drive device upratvleniya, rails by flexible elastic pipelines.

In the design of such a coordinate table, large forces of resistance to its movement arise, which are determined by significant friction forces in the sealing elements of the hydrostatic guides and the hydraulic cylinders of the coordinate table, sealed with sliding lip seals. Moreover, the hydraulic cylinder rods are additionally sealed against leakage of the working fluid into the process volume (vacuum chamber) by metal bellows, from which additional resistance forces arise due to their elastic deformation, changing both in magnitude and direction. In addition, when moving the carriages of the coordinate table, resistance forces arise from elastic deformation of the walls of the flexible pipelines, preventing it from moving. As a result of this, the starting currents of the hydraulic motor increase, leads to an increase in the dead zone of the coordinate table, which is directly proportional to the forces of resistance to movement, and significantly reduces positioning accuracy, and energy consumption increases. The dynamic characteristics of the coordinate table deteriorate, for example, the smoothness of movement, the nature and magnitude of the transition characteristics, etc. The presence in the design of the coordinate table of well-known typical hydrostatic guides does not allow for continuous adjustment of their time in automatic mode or continuous automatic stabilization of the position of the product mounted on the upper carriage along six spatial coordinates - X, Y, Z, α _x , α _y , α _z .

 Due to the fact that the hydraulic table control device uses electro-hydraulic transducers that contain moving inertial elements moving in a viscous medium, such as membranes, springs, electromagnets, spools, which therefore have a large response time, the speed of the coordinate table hydraulic drives is significantly reduced. The use of flexible flexible hoses as pipelines leads to the same result due to the elastic deformation of the walls. The presence of significant frictional forces and variable cyclic loads in the sealing nodes of hydrostatic guides and hydraulic cylinders, as well as in the moving elements of their control devices, leads to rapid wear of friction surfaces, clogging of wear products of the throttling channels of hydrostatic guides, regulators of the flow rate of the working fluid of hydrostatic guides, control devices for hydraulic actuators of electro-hydraulic type and failure of these devices, and therefore, to reduce the reliability of dinati table as a whole.

 The aim of the invention is to increase the accuracy of positioning, speed, reliability, expansion of functionality, improvement of dynamic characteristics and technological settings of the coordinate table.

 The goal is achieved in that the coordinate table is equipped with hydrostatic guides of cylindrical shape, each of which is equipped with two hydrostatic supports located at a basic distance from each other, each of which consists of two high-pressure chambers located in the vertical plane and two located in the horizontal plane, each of the high-pressure chambers is hydraulically connected to the pumping station through a magnetorheological throttle, located around each high-pressure chamber s low pressure chamber. In order to improve positioning accuracy, reliability and speed, cylindrical hydrostatic guides are sealed with sealing elements made in the form of elastic thin-walled shells in the form of bodies of revolution, installed with the possibility of rolling between a cylindrical hydrostatic guide and the corresponding carriage. In addition, in order to improve positioning accuracy, speed, reliability and improve dynamic characteristics, the drives are made in the form of two pairs of hydraulic motors for driving the lower and upper carriages, respectively, and each of the pairs of hydraulic motors is equipped with two pushers connected to opposite sides of the respective carriages sealed in the housings hydraulic motors using elastic thin-walled shells in the form of bodies of revolution, installed with the possibility of rolling the latter between the pusher and hydraulic motors and housings, each pair of hydraulic motors fluidly connected to the pumping station via magnetorheological distributor consisting of four magnetorheological throttles, included in a bridge circuit.

 For the same purpose, a pair of hydraulic motors leading the upper carriage is hydraulically connected to the magnetorheological distributor and the pump station through two pairs of hydraulic transmission units, and cylindrical hydrostatic guides mounted on the lower carriage are hydraulically connected to the pump station through two other pairs of hydraulic transmission units, the latter made in the form of hollow pushers located coaxially and parallel to the direction of movement of the lower carriage in each pair of hydraulic transmission units, simply connected to the lower carriage and sealed in the bodies of the hydraulic transmission units using thin-walled shells in the form of bodies of revolution mounted with the possibility of rolling between hollow pushers and the bodies of the hydraulic transmission units. In order to expand functionality, increase reliability, speed and reduce energy consumption by creating gradient magnetic field forces, magnetorheological chokes are made in the form of a magnetic field inductor enclosed by a magnetic circuit consisting of a glass, a pole cylindrical spacer and a pole washer forming a cylindrical annular throttling channel, trapezium-shaped teeth are made on at least one of the pole parts of the magnetic circuit, the troughs of which are filled with a diamagnet th material. In order to increase reliability and speed, the sealing elements are made in the form of elastic thin-walled shells in the form of axial bodies of revolution. In order to increase reliability and expand the functionality of the coordinate table, the pole cylindrical spacer of the magnetorheological choke is made thin-walled from a ferromagnetic elastic material. For the same purpose, the annular part of the pole washer of the magnetorheological throttle is equipped with a partition with channels for diverting the working fluid and stops of diamagnetic material, and the inside of the thin-walled pole cylindrical spacer from the side of the pole washer is equipped with a partition of ferromagnetic material, and the pole spacer is mounted with axial movement.

 Figure 1 shows the structural diagram of the coordinate table, top view; in FIG. 2 shows a section aa in figure 1 - in the vertical plane of the hydrostatic guide of the lower carriage of the coordinate table; figure 3 is a section bB in figure 2 - along the axis of the hydrostatic support hydrostatic guide; in FIG. 4 - section bb in figure 2 - low-pressure chambers hydrostatic guide; in Fig.5 - node I in Fig.2 - fastening the sealing element of the hydrostatic guide; in Fig.6 is a section GG in Fig.2 - in the horizontal plane of the hydrostatic guide of the lower carriage of the coordinate table; in Fig.7 - section DD in Fig.1 - in the vertical plane of the hydraulic motor coordinate table; in Fig.8 is a section EE in Fig.7 - a hydraulic motor in the place of connection of the pipeline; in Fig.9 - node II in Fig.7 - mounting the sealing element of the hydraulic motor; figure 10 - section FJ in figure 1 - in the vertical plane of the hydraulic unit; in Fig.11 - node III in Fig.10 - fastening the sealing element of the hydraulic transmission unit; in Fig.12 - section II; in Fig.10 - hydraulic transmission unit at the junction of the hollow pusher with the bottom carriage of the coordinate table; on Fig - magnetorheological dispenser; on Fig is a section of a magnetorheological distributor along the channel of the removal of the working fluid; on Fig - section KK in Fig.13; in Fig.16 - magnetorheological throttle; in Fig.17 - magnetorheological choke with a thin-walled cylindrical pole spacer made of ferromagnetic elastic material; Fig. 18 shows a magnetorheological choke with a baffle in a pole washer and a thin-walled cylindrical pole spacer.

 The coordinate table (Fig. 1) contains a fixed base 1, a lower carriage 2 mounted for movement on a fixed base, an upper carriage 3 mounted on a lower carriage with the ability to move perpendicular to the direction of movement of the lower carriage, four hydrostatic guides 4-7 of a cylindrical shape, four hydraulic motors 8-11, eight hydraulic transmission units 12-19, two magnetorheological distributors 20,21, three pumping stations 22,23,24, coordinate table drive control system 25, control system 26 phenomena hydrostatic guides of the coordinate table, system 27 for measuring the movement of the coordinate table. The lower carriage 2 is mounted on a fixed base 1 with the ability to move along two hydrostatic rails 4,5, and the upper carriage 3 - along two hydrostatic rails 6,7. In addition, hydrostatic guides 4,5 of a cylindrical shape for moving the lower carriage 2 are hydraulically connected to the pump station 22, and hydrostatic guides 6,7 of a cylindrical shape for moving the upper carriage 3 are hydraulically connected also to the pump station 22 through two pairs of hydraulic transmission units 12,13 and 14.15 mounted on a fixed base 1 coaxially and parallel to the direction of movement of the lower carriage 2 in each pair of hydraulic transmission units 12,13 and 14,15. To drive the lower carriage 2, a pair of hydraulic motors 10,11 is mounted on a fixed base, connected to opposite sides of the lower carriage, mounted coaxially and parallel to the direction of its movement and hydraulically connected to the pump station 23 through a magnetorheological distributor 20. To drive the upper carriage 3 on the lower carriage 2 a pair of hydraulic motors 8.9 is fixed, connected to opposite sides of the upper carriage 3 and hydraulically connected to the pumping station 24 through two pairs of hydraulic transmission units 16.17 and 18.19, mounted on a fixed base 1 coaxially in each pair and installed parallel to the direction of movement of the lower carriage 2, and through the magnetorheological distributor 21.

 The fixed base 1 serves to fix on it cylindrical hydrostatic guides 4,5 for moving the lower carriage 2, hydraulic motors 10,11 and four pairs of hydraulic transmission units 12,13 and 14,15, and 16,17, and 18,19.

 The lower carriage 2 serves to secure a cylindrical hydrostatic guide 6,7 on it to move the upper carriage 3, two hydraulic motors 8,9, provides movement of the product mounted on the upper carriage 3, in the X direction and contains a plate 28, two cases 29, fixed on the plate 28, four cylindrical cups 30, mounted on each end of the housing 29, the rack 31 and four racks 32.

 The upper carriage 3 is used to install products and mirrors on it of the system 27 for measuring the movement of the coordinate table and moving it in the Y direction and contains a plate 33, two racks 34, two cases 29, mounted on the plate 33, four cylindrical glasses 30, mounted on each end housing 29.

 Hydrostatic guides 4,5 and 6,7 [Fig.2-6] of a cylindrical shape are designed to move along them the lower carriage 2 and the upper carriage 3, respectively, and contain a cylindrical rod 35 mounted on two adjustable supports 36, along the longitudinal axis of which are located on the base distance from each other are two hydrostatic supports 37 and 38. Each of the latter consists of two high-pressure chambers 39.40 and 41.42 located respectively in the vertical plane and two high-pressure chambers 43.44 and 45.46 respectively pressure, respectively, and around each high-pressure chamber are four chambers 47 of low pressure (discharge). The latter are hydraulically connected to the corresponding high-pressure chamber through a radial annular throttling channel 48 formed by the outer cylindrical surface of the hydrostatic support 37.38 and the inner cylindrical surface of the housing 29, located coaxially. At the entrances to each of the 39,40,41,42,43,44,45,466 high-pressure chambers, magnetorheological chokes 49,50,51,52,53,54,55,56, respectively, are installed, fastened in four on two opposite ends cylindrical rod 35 using flanges 57 and 58. High-pressure chambers 39,40,41,42,43,44,45,46 are hydraulically connected by hydraulic channels 59 to magnetorheological chokes 49,50,51,52,53,54,55,56 respectively, and the latter are hydraulically connected to the supply pipelines 60 through flanges 61. The low-pressure (discharge) chambers 47 are hydraulically connected to the discharge pipes by wires 62 by hydrochannels 63. The cavities of hydrostatic guides 4,5,6,7 formed by a cylindrical rod 35 and a cylindrical surface of the housing 29 are sealed from the side of its ends by sealing elements 64 in the form of thin-walled elastic shells in the form of bodies of revolution, which can be rolled between the housing 29 and a cylindrical rod 35. One end of the sealing element 64 is attached to the housing 29 using a cylindrical cup 30, an elastic gasket 65 and a rigid ring 66, and the other to the cylindrical rod 35 of the elastic pad 67 and the rigid ring 68.

 Hydraulic motors 8-11 (Figs. 7-9) are intended for the precision movement of the upper carriage 3 in the Y direction and the lower carriage 2 in the X direction, respectively. They are installed in pairs and coaxially in each pair. The hydraulic motor includes a cylindrical body 69, mounted in an adjustable support 70 and connected to the pipe 71 through a gasket 72 and a sleeve 73, a hollow cylindrical pusher 74, plugged by a plug 75 and fixedly mounted on the rack 31 or 34, a cylindrical cup 76, mounted coaxially on the end of the cylindrical body 69, a sealing element 77 in the form of an elastic thin-walled shell in the form of a body of revolution, mounted with the possibility of rolling between the cylindrical body 69 and the hollow cylindrical pusher 74, and and the end of the sealing element 77 is fixed to the hollow cylindrical pusher 74 with a sleeve 78, a nut 79, a rigid ring 80 and an elastic gasket 81, and the other in a cylindrical body 69 with a cylindrical glass 76, a rigid ring 82 and an elastic gasket 83.

 Hydraulic transmission units 12-19 (Fig.10-12) are designed to provide a rigid, almost elastically non-deformable, movable hydraulic connection of the elements of the coordinate table. They are installed in pairs and coaxially in each pair. The hydraulic transmission unit includes a cylindrical body 84, mounted in an adjustable support 85, connected to the pipe 86, a cylindrical cup 87, mounted on the end of the cylindrical body 84, a hollow cylindrical pusher 88, rigidly mounted on the rack 32, and the inner cavity of the hollow cylindrical pusher 88 is hydraulically connected to the cavity of the cylindrical body 84, the sealing element 89 in the form of an elastic thin-walled shell in the form of a body of revolution, mounted with the possibility of rolling between the cylindrical a casing 84 and a hollow cylindrical pusher 88. One end of the sealing element 89 is fixed to the hollow cylindrical pusher 88 with a rigid ring 90, an elastic gasket 91, a nut 92 and a sleeve 93, and the other on a cylindrical body 84 with a cylindrical glass 87, a rigid ring 94 and an elastic gasket 95. The rack 32 through two hydraulic channels 96 are hydraulically connected to two pipelines 97 using gaskets 98 and bushings 99.

 Magnetorheological distributors 20,21 (Fig.13-15) are designed to control hydraulic motors 10.11 and 8.9 drives of the lower carriage 2 and the upper carriage 3, respectively. The magnetorheological distributor comprises a housing 100 in which four magnetorheological chokes 101-104 are mounted, connected in a bridge circuit, each of which is sealed in the housing 100 by two rings 105. A boss 106 and a flange 107 are mounted in the axial direction between each magnetorheological choke 101,104 and the housing 100. having a hydrochannel 108. Magnetorheological chokes 102,103 are installed in the housing 100 in the axial direction through the boss 106, and two pairs of magnetorheological chokes 101,102 and 103,104 are separated in each pair by a flange 109, having conductive waterway groove 110. The discharge line 111 is attached to the housing 100 via a gasket 112 and fluidically connects the valve with the respective magnetorheological pumping station. The magnetorheological chokes 101,104 are hydraulically connected to the discharge pipe 111 by the hydraulic channels 113 in the housing 100 and the hydraulic channels 108 in the flanges 107. The supply pipe 114, which hydraulically connects a pair of magnetorheological chokes 102,103 to the corresponding pump station, is fixed to the housing 100 through the gasket 112. The supply pipe 114 is hydraulically connected to magnetorheological chokes 102,103 through hydraulic channels 115 and 116 in the housing 100. Pipelines 117 and 118 are mounted on the housing 100 through gaskets 112 and are hydraulically connected ares magnetorheological inductors 101,102 and 103,104, respectively, through water channels 110 in the flanges 109 and through the water channels 120,121 in the body 100 with the respective hydraulic motors. Through four channels 119 in the housing 100, the control electric signals are supplied to the magnetic field inductors 129 of the magnetorheological chokes 101,102,103,104.

 Pumping stations 22,23,24 (figure 1) are designed to provide the necessary constant flow rate of the working fluid — magnetorheological suspension in the hydraulic line of consumers and create the required pressure values in high-pressure chambers of hydrostatic guides and in hydraulic motors. They provide the work of hydrostatic guides 4,5,6,7 of a cylindrical shape, hydraulic motors 10,11 leading the lower carriage 2, hydraulic motors 8,9 leading the upper carriage 3, respectively. Each pump station contains a hydraulic pump 122, a safety valve 123, a pressure gauge 124, a tank 125, a working fluid - magnetorheological suspension 126 and a heat exchanger 127.

 The coordinate table drive control system 25 (FIG. 1) is designed to control precision movements along the X and Y coordinates of the lower carriage 2 and the upper carriage 3 of the coordinate table by means of hydraulic motors 10.11 and 8.9 and magnetorheological distributors 20.21, respectively.

The control system 26 of the guides of the coordinate table (Fig. 1) is designed to control adjustment movements along the coordinates X, Y, Z, α _x , α _y , α _{z of} hydrostatic guides 4,5,6,7 of a cylindrical shape necessary to move the lower carriage 2 and the upper carriage 3, respectively, by means of the respective magnetorheological chokes mounted on their ends.

The system 27 for measuring the movement of the coordinate table (Fig. 1) is designed for continuous non-contact measurement of the values of the current coordinates (X, Y, Z, α _x , α _y , α _z ) of the spatial position of the coordinate table and determining the direction of its movement. It contains a mirror 128, mounted on a plate 33 of the upper carriage 3, a six-coordinate interferometer with an electronic unit for the initial processing of information.

 Magnetorheological chokes 49-56 and 101-104 (Fig. 16) are designed to control the flow rate of the working fluid - magnetorheological suspension, supplied to the high-pressure chambers of hydrostatic guides and hydraulic motors of the coordinate table. The magnetorheological choke comprises a magnetic field inductor 129, enclosed by a magnetic circuit consisting of a cup 130, a cylindrical pole spacer 131, a pole washer 132, forming a cylindrical annular throttling channel 133, and on the cylindrical pole spacer 131 there are made trapezium teeth 134 whose troughs are filled with diamagnetic material . The magnetic field inductor 129 is sealed between the cup 130 and the pole washer 132 with gaskets 135. The pole washer 132 and the cup 130 are connected by a ring 136, and the pole cylindrical spacer 131 is attached to the cup 130 by a screw 137 through the washer 138.

 The magnetorheological throttle in FIG. 17 is intended to expand the control range of the flow rate of the working fluid — the magnetorheological slurry supplied to the high-pressure chambers of the hydrostatic guides and the hydraulic motors of the coordinate table, as well as to increase reliability and expand functionality. It contains a magnetic field inductor 129, enclosed by a magnetic circuit consisting of a cup 130, a thin-walled pole cylindrical spacer 139 made of ferromagnetic elastic material, a pole washer 140, forming a cylindrical annular throttling channel 133, and the teeth 134 made in the form of a trapezoid are made on the pole washer 140 troughs filled with diamagnetic material. The magnetic field inductor 129 is sealed between the cup 130 and the pole washer 140 with gaskets 135. The pole washer 140 and the cup 130 are connected by a ring 136, and a thin-walled pole cylindrical spacer 139 is attached to the cup 130 by a screw 137 through the washer 138.

 The magnetorheological choke in FIG. 18 is intended to expand the range of regulation of the flow rate of the working fluid — the magnetorheological suspension supplied to the high-pressure chambers of the hydrostatic guides and the hydraulic motors of the coordinate table, as well as to increase reliability and expand the functionality. It contains a magnetic field inductor 129 covered by a magnetic circuit consisting of a cup 130, a pole washer 141, on the inner cylindrical surface of which teeth 134 are made in the form of a trapezoid, the troughs of which are filled with diamagnetic material, a thin-walled pole cylindrical spacer 139, in which from the side of the pole washer 141 a partition 142 made of ferromagnetic material is installed, and the pole cylindrical spacer 139 is installed with the possibility of axial movement, and in the annular part of the pole washer 141 installed campus 143 with outlet channels of the working fluid on which fixed abutments 144 of diamagnetic material. The magnetic field inductor 129 is sealed between the cup 130 and the pole washer 141 by gaskets 135. The pole washer 141 and the cup 130 are connected by a ring 136, and the thin-walled pole cylindrical spacer 139 is attached to the cup 130 by a screw 137 through the washer 138.

 The coordinate table works as follows.

 Initially, a constant flow rate of the working fluid — magnetorheological slurry 126 — is supplied to each of the chambers 39-46 (FIGS. 1, 2, 6) of a high-pressure cylindrical hydrostatic guide from the hydraulic pump 122 of the pump station 22. Moreover, to supply the hydrostatic guides 4,5 to the lower carriages 2 working fluid — magnetorheological slurry 126 flows through inlet pipelines 60 through flange 61, magnetorheological chokes 49-56, hydraulic channels 59, high pressure chambers 39-46, radial ring throttles channels 48, chambers 47 of low pressure (discharge) and is discharged through the discharge pipelines 62 to the tank 125 of the pump station 22 through the heat exchanger 127. To supply the hydrostatic guides 6.7 of the cylindrical shape of the upper carriage 3, the working fluid — magnetorheological suspension 126 flows through the hydraulic transmission units 12, 13, inlet pipelines 60, flanges 61, magnetorheological chokes 49-56, hydrochannels 59, high pressure chambers 39-46, radial ring throttling channels 48, low pressure chambers 47 (discharge) and are discharged into the pumping tank 125 with 22 through the discharge pipelines 62, the hydraulic transfer units 15.14 and the heat exchanger 127 of the pump station 22. Under the action of the generated high pressure in the chambers 39-46 of the hydrostatic guides 4,5,6,7 of the cylindrical shape of the housing 29, rigidly connected to the plates 28,33 respectively, the lower carriage 2 and the upper carriage 3, "pop up" on the hydrostatic bearings 37.38 and can move along the hydrostatic guides 4,5,6,7 from the hydraulic motors 8,9 and 10,11.

 To move the bottom carriage 2, for example, to the right along the X axis, the flow rate of the working fluid — magnetorheological suspension 126 from the hydraulic pump 122 of the pump station 23 enters through the supply pipe 114 through the magnetorheological distributor 20 into the hydraulic motor 11. Moreover, in the cylindrical body 69 (Fig. 7) a pressure is created that acts on the end of the pusher 74, drowned by the plug 75, the pusher 74 is rigidly connected to the lower carriage 2 by the other end 2. Moreover, magnetorheological chokes 101,103 (Fig. 13) are magnetorheological distribution The actuator 20 is in the “closed” state, and the magnetorheological chokes 102,104 of the magnetorheological distributor 20 are in the “open” state. As a result of the movement of the lower carriage 2, the working fluid — magnetorheological suspension 126 is displaced from the hydraulic motor 10 by the end of the pusher 74, plugged by the plug 75, into the tank 125 of the pump station 23 through the magnetorheological distributor 20, outlet pipe 107, heat exchanger 127. To move the lower carriage 2, for example, to the left along the X axis, the state of the magnetorheological chokes 101,102,103,104 of the magnetorheological distributor 20 must be reversed - the magnetorheological chokes 101,103 are in the "open" state, and Theoretical chokes 102.104 - in the closed state. In this case, the flow rate of the working fluid — the magnetorheological suspension 126 from the hydraulic pump 122 of the pump station 23 — enters the hydraulic motor 10 through the magnetorheological distributor 20, forcing the pusher 74, rigidly connected to the lower carriage 2, to move. The working fluid — the magnetorheological suspension 126 is forced out by the end of the plunger 74 of the hydraulic motor 11 , merges into the tank 125 of the pumping station 23 through the magnetorheological distributor 20, the discharge pipe 111 and the heat exchanger 127. The operating procedure of the drive, moving the The upper carriage 3 along the Y axis is carried out similarly to the movement of the lower carriage 2 along the X axis. Moreover, the flow of the working fluid — magnetorheological slurry 126 from the hydraulic pump 122 of the pump station 24 goes to the hydraulic motors 8 and 9 and is diverted from them through the hydraulic transmission units 16,17 and 18, nineteen.

=

· μ(I) (1) где R_МРД ^(I) - гидравлическое сопротивление магнитореологического дросселя;
I - ток в индукторе магнитного поля;
Δ Р_МРД - перепад давления на магнитореологическом дросселе;
q_МРД - расход через магнитореологический дроссель;
l - длина дросселирующего цилиндрического канала магнитореологического дросселя в направлении течения магнитореологической суспензии;
D - средний диаметр дросселирующего цилиндрического канала;
S - кольцевой зазор дросселирующего цилиндрического канала;
μ (I) - зависимость динамической вязкости от тока в индукторе магнитного поля.The principle of operation of magnetorheological chokes 101-104 in magnetorheological distributors 20 and 21 and magnetorheological chokes 49-56 in hydrostatic guides 4-7 is based on the use of the magnetorheological effect - a reversible change in dynamic viscosity up to solidification of a suspension of finely dispersed ferromagnetic particles in a liquid medium - magnetorheological suspension 126 under the action of an external magnetic field superimposed on it when flowing in a cylindrical annular throttling channels 133 (Fig.16-18) magnet halogen chokes. As a result of this effect, the hydraulic resistance of the magnetorheological chokes changes
R _MRD (I) =

=

Μ (I) (1) where R _МРД ^(I) is the hydraulic resistance of the magnetorheological throttle;
I is the current in the magnetic field inductor;
Δ R _MRD - pressure drop across the magnetorheological throttle;
q _MRD - flow rate through the magnetorheological throttle;
l is the length of the throttling cylindrical channel of the magnetorheological throttle in the direction of flow of the magnetorheological suspension;
D is the average diameter of the throttling cylindrical channel;
S is the annular gap of the throttling cylindrical channel;
μ (I) is the dependence of the dynamic viscosity on the current in the magnetic field inductor.

· μ(I) = P_н-P(I) (2) где Р_н - давление гидронасоса (давление перед магнитореологическим дросселем);
Р(I) - давление, например, в камере высокого давления гидростатической направляющей (давление за магнитореологическим дросселем);
q_МРД - const;
P_н - const, позволяющую пояснить принцип осуществления управляемых юстировочных перемещений гидростатических направляющих 4,5,6,7 цилиндрической формы и принцип работы магнитореологического следящего гидропривода координатного стола. Так, независимо управляя величинами давления рабочей жидкости P(I) во всех камерах высокого давления гидростатических направляющих цилиндрической формы, можно непрерывно в процессе работы стола управлять величинами их подъемной силы, а следовательно, пространственным положением нижней и верхней кареток координатного стола.Thus, by ensuring a constant flow rate q of the _{MAJP of the} magnetorheological suspension through the magnetorheological throttle, a fundamental analytical dependence is obtained
ΔP _MRD (I) = q _MRD

Μ (I) = P _n -P (I) (2) where P _n is the pressure of the hydraulic pump (pressure in front of the magnetorheological throttle);
P (I) is the pressure, for example, in the high-pressure chamber of the hydrostatic guide (pressure behind the magnetorheological throttle);
q _mrd - const;
P _n - const, which allows to explain the principle of controlled adjustment movements of hydrostatic guides 4,5,6,7 of a cylindrical shape and the principle of operation of a magnetorheological servo hydraulic drive coordinate table. So, independently controlling the pressure values of the working fluid P (I) in all high-pressure chambers of cylindrical hydrostatic guides, it is possible to continuously control the values of their lifting force during the operation of the table, and therefore the spatial position of the lower and upper carriages of the coordinate table.

The precision positioning of the coordinate table in six coordinates: three linear - X, Y, Z (Fig. 1) and three angular - α _x , α _y , α _{z is} carried out in two stages. First, the coordinate table is positioned relative to the "rough" positioning step, including hydraulic motors 8-11. Upon reaching a positioning accuracy equal to the dead zone of the coordinate table, the adjustment process begins using the step of "exact" positioning across all six spatial coordinates, based on a targeted change in the dynamic viscosity of the cylindrical working fluid flowing in hydrostatic guides 4-7 - magnetorheological suspension 126 under by the action of an external magnetic field superimposed on it in magnetorheological chokes 49-56 and associated HAND redistribution of the pressure in the high pressure chambers 39-46 of hydrostatic guides of cylindrical shape, resulting in a corresponding change in the radial throttle annular channel 48 and hence to the parallel displacement or inclination of the bottom of the carriage 2 and the carriage 3 upper coordinate table. For example, alignment movement along the Y axis (FIG. 1) can only be achieved by changing the magnitude of the radial annular throttling channel 48 located between the horizontal pressure chambers 43-46 (FIG. 6) and the low-pressure chambers 47 of the hydrostatic guides 4,5 of the cylindrical forms. The adjustment turn around the Y axis (Fig. 1) is carried out by changing the magnitude of the radial annular throttling channel 48 located between the vertical chambers 39-42 (Fig. 2) of high pressure and the low-pressure chambers 47 of the hydrostatic guides 4,5 of a cylindrical shape. Similarly, by changing the corresponding values of the radial annular throttling channels 48 of the hydrostatic guides 6.7 of a cylindrical shape, it is possible to carry out precise movements along and turning around the spatial axes X, Y, Z. As an example, we consider the process of "accurate" positioning of the coordinate table in the ZOY plane (Fig. 1) and the operation of the cylindrical hydrostatic guide 6. The hydrostatic guide 7 should work similarly.

, а управляющие сигналы при этом следующие: U₁ = U_z - U_Δz ; U₂ = U_z + U_Δz U₃=U

-U

; U₄=U

+U

. Управляющие сигналы U₁, U₂, U₃,U₄ вырабатываются цифроаналоговыми преобразователями. Преобразованные управляющие сигналы U₁...U₄ в соответствующие управляющие токовые сигналы I₁. . .I₄ подаются на индуктор 129 магнитного поля магнитореологических дросселей 49-56. Наложение магнитного поля на рабочую жидкость - магнитореологическую суспензию 126, протекающую через магнитореологические дроссели 49-56 по цилиндрическому кольцевому дросселирующему каналу 133, приводит к повышению ее динамической вязкости, а следовательно, к увеличению гидравлического сопротивления магнитореологического дросселя (см.формулу (1)). В результате возрастает перепад давления Δ Р_МРД (см.формулу (2)) на магнитореологическом дросселе, что позволяет регулировать давление в камерах 39-46 высокого давления. В результате подачи управляющих токовых сигналов I₁ на магнитореологические дроссели 49,51, а I₂ на магнитореологические дроссели 50,52 в соответствующих камерах 39,41 высокого давления величина давления возрастает, а в камерах 40,42 - давление уменьшается, что вызывает перемещение верхней каретки 3 вверх по оси Z.Let, for example, you need to move the upper carriage 3 up along the Z axis and rotate around the X axis. From the six-coordinate laser interferometer, which constantly monitors the spatial position of the coordinate table, the current coordinates (X, Y, Z, α _x , α _y , α _z ) are received in the form of analog signals from its photodetectors to an electronic unit for the initial processing of information, where they are converted into a digital code and compared with the programmed digital codes of coordinates of the coordinate table, i.e. in this case, the digital codes come from the coordinate table displacement measuring system 27 along the coordinates Z and α _x , are compared in the coordinate table guide control system 26 with the programmed digital coordinate codes Z 'and α _x ′, and the value and sign of the coordinate mismatch are determined (ΔZ = Z '= Z; Δα _x = α _x ′ -α _x ). After comparison in the coordinate table guide system 26 for controlling the guiding table, the digital coordinates ΔZ and Δα _{x of the} coordinate mismatch, taking into account the signs, are simultaneously digital codes of control actions, which, in accordance with the guide control algorithm, must be supplied as converted analog current signals to the corresponding magnetic field inductors 129 magnetorheological chokes 49-56 hydrostatic guides 6.7. In the case under consideration, Δ Z = (Z '- Z)> 0 and Δα _x = (α _x ′ -α _x )> 0, therefore, the equivalent control actions are U _Δz and U

, and the control signals are as follows: U ₁ = U _z - U _Δz ; U ₂ = U _z + U _Δz U ₃ = U

-U

; U ₄ = U

+ U

. The control signals U ₁ , U ₂ , U ₃ , U _{4 are} generated by digital-to-analog converters. The converted control signals U ₁ ... U ₄ into the corresponding control current signals I ₁ . . .I ₄ are supplied to the magnetic field inductor 129 of the magnetorheological chokes 49-56. The application of a magnetic field to the working fluid — magnetorheological slurry 126, flowing through magnetorheological chokes 49-56 through a cylindrical annular throttling channel 133, increases its dynamic viscosity and, consequently, increases the hydraulic resistance of the magnetorheological choke (see formula (1)). As a result, P increases Δ _MRD pressure drop (sm.formulu (2)) to the magnetorheological throttle that allows to adjust the pressure in the high pressure chambers 39-46. As a result of the supply of control current signals I ₁ to the magnetorheological chokes 49.51, and I ₂ to the magnetorheological chokes 50.52 in the corresponding pressure chambers 39.41, the pressure increases, and in the chambers 40.42 the pressure decreases, which causes the upper carriages 3 up along the Z axis.

As a result of this, lifting forces arise due to the pressure difference in the vertical high-pressure chambers 39,40,41,42 of cylindrical hydrostatic guides. As a result of this, the housings 29, which are rigidly connected to the upper carriage 3, move in the direction of the Z axis. As a result of the supply of control current signals I ₃ to magnetorological chokes 50.51, and I ₄ to magnetorheological chokes 49.52 in the corresponding high-pressure chambers 40.41 the pressure increases, and in the chambers 39,42 the pressure decreases, which causes an angular rotation of the upper carriage 3 around the axis X.

Due to this redistribution of pressures, a lifting force arises due to the pressure difference in the vertical high pressure chambers 41,42 and a lowering force due to the pressure difference in the vertical high pressure chambers 39,40, which causes the bodies 29 rigidly connected to the upper carriage 3 to unfold around the X axis. The upper carriage 3 moves in such a way until the digital codes ΔZ and Δα _{x of the} coordinate mismatch become zero. In the considered example of adjustment movement using the step of "exact" positioning of the coordinate table in the ZOY plane, a mismatch of the current coordinates along the Y axis can occur, which is eliminated by the adjustment movement carried out by hydrostatic guides 4,5 of cylindrical shape, working similarly, only in this case pressure redistribution occurs in horizontal chambers 43-46 high pressure. Thus, it is possible to carry out continuous adjustment movements along six coordinates - X, Y, Z, α _x , α _y , α _z .

+

+

(3)
где f_тр - площадь проходного сечения трубопровода;
d_тр - внутренний диаметр трубопровода;
L_тр - суммарная длина соединительного трубопровода;
Е_тр - модуль упругости материала трубопровода;
F_тр - площадь толкателей гидродвигателей;
α_тр - толщина стенки трубопровода;
h - ход толкателя гидродвигателя;
Е_ж. - объемный модуль упругости рабочей жидкости.Four pairs of coaxially located hydraulic transmission units 12 and 13, 14 and 15, 16 and 17, 18 and 19 are introduced in order to exclude carriage turns on hydrostatic guides 4,5,6,7 arising from different-sized working pressures in the housings 69 hydraulic motors 8,9,10,11, as well as in the cases of 84 hydraulic transmission units 12,13,14,15,16,17,18,19. The coordinate table due to the small radial stiffness of the used rolling elastic sealing elements 64,77,89 in the form of thin-walled shells in the form of bodies of revolution is unloaded from the forces of resistance to movement. A thin-walled shell under the pressure of the working fluid is pressed against the cylindrical surfaces of the cups 30.76.87, the rod 35 and the pushers 74 and 88, covering it. As a result, the inner and outer surfaces of the shell do not experience friction during the movement of the coordinate table. To increase speed and reliability, sealing elements 64.77.89 in the form of thin-walled shells in the form of bodies of revolution can be reinforced in the axial direction, for example, with fiberglass threads, which significantly increases their axial stiffness and pressure loading. Thanks to the use of hydraulic transmission units 12-19, a movable, but at the same time rigid (almost elastically non-deformable) pipeline for supplying a working fluid — magnetorheological suspension 126 to hydraulic motors 8.9 and hydrostatic guides 6.7 of a cylindrical shape mounted on a movable lower carriage 2 is realized. this does not require time to create an additional expense to compensate for the elastic deformation of the walls of the pipelines (as, for example, the case with rubber hoses), which is significant increases the speed of the actuator, and hence the coordinate table as a whole, in addition, does not introduce any undesirable disturbances (vibrations, etc.) on the moving carriage the sudden change in the operating pressures in the pipes. The total compressibility coefficient of the pipeline and the working fluid located in the pipeline and the cavities of the hydraulic motors is
C _{compression mp} = f _mp

+

+

(3)
where f _Tr - the flow area of the pipeline;
d _Tr - the inner diameter of the pipeline;
L _Tr - the total length of the connecting pipeline;
E _Tr - the modulus of elasticity of the material of the pipeline;
F _Tr - the area of the pushers of hydraulic motors;
α _Tr - the wall thickness of the pipeline;
h is the stroke of the pusher of the hydraulic motor;
E _w . - volumetric modulus of elasticity of the working fluid.

(4) где Δ Р - перепад давления на толкателях гидродвигателя;
t - время.Loss of flow to compensate for elastic deformation of the pipeline and the working fluid in the cavities of hydraulic motors
Q _{compression mp} = C _{compression mp}

(4) where Δ P is the pressure drop across the hydraulic drive pushers;
t is time.

+ Q_сж.тр+Q_сж.об.+Q_ут (5) где Х - перемещение толкателей;
Q_сж.об - потери расхода на компенсацию осевого упругого деформирования герметизирующего эластичного элемента (тонкостенная оболочка);
Q_ут - потери расхода на компенсацию утечек рабочей жидкости (равны нулю, так как утечек нет и полная герметизация).Required fluid flow rate
Q _p = F _t

+ Q _{compression tr} + Q _compression + Q _ut (5) where X is the movement of the pushers;
Q _compress.ob - loss of flow for compensation of axial elastic deformation of the sealing elastic element (thin-walled shell);
Q _ut - loss of flow to compensate for leaks of the working fluid (equal to zero, since there are no leaks and complete sealing).

=

(6) где I_тр.дв - ток трогания гидродвигателя или гидростатической направляющей, подаваемый на соответствующие магнитореологические дроссели координатного стола;
(К_д˙К_у) - коэффициент усиления системы измерения положения координатного стола;
К_д - коэффициент передачи датчика положения координатного стола;
К_у - коэффициент усиления измерительного усилителя;
Т_напр - сила трения в направляющих координатного стола;
Т_г - сила сопротивления, возникающая от герметизирующих элементов привода и гидростатических направляющих координатного стола;
Т_сопр - сила сопротивлению перемещению координатного стола, возникающая от воздействия атмосферного давления на герметизирующие элементы привода и гидростатических направляющих, веса стола и т.д.Thus, according to formula (3), the smaller the compressibility coefficient of the pipeline, the more it is possible to assume a larger gradient of the pressure drop across the hydraulic motor followers, i.e. to create the required pressure drop for moving hydraulic motors in a shorter time t and thereby increase the speed of the coordinate table. In addition, due to a significant decrease (almost to zero) of the resistance forces to the movement of the coordinate table arising from the operation of sealing elastic elements, the dead zone of the coordinate table is significantly reduced:
δ _t =

=

(6) where I _tr.dv is the starting current of the hydraulic motor or hydrostatic guide supplied to the corresponding magnetorheological chokes of the coordinate table;
(K _d ˙K _y ) is the gain of the coordinate table position measuring system;
To _d - the transmission coefficient of the position sensor of the coordinate table;
To _y is the gain of the measuring amplifier;
T _nap - the friction force in the guides of the coordinate table;
T _g - resistance force arising from the sealing elements of the drive and hydrostatic guides of the coordinate table;
T _sop - the resistance to movement of the coordinate table arising from the influence of atmospheric pressure on the sealing elements of the drive and hydrostatic guides, the weight of the table, etc.

 Therefore, according to the formula (6), the accuracy of positioning is increased. In addition, speed and reliability are ensured by the absence of movable inertial elements, for example, membranes, spools, springs, electromagnet anchors, etc., in the magnetorheological distributor and magnetorheological chokes, which require time-consuming operation. Thanks to the use of magnetorheological throttles, the range of regulation of working pressures in the chambers 39-46 of hydrostatic guides extends, which expands the functionality of the coordinate table, namely, increases the load capacity.

 Magnetorheological chokes 49-56, 101-104 (Fig.16, 17, 18) work as follows.

 The working fluid - magnetorheological suspension 126 under a certain pressure enters the cylindrical annular throttling channel 133, passes it and enters the hydraulic line of the connected hydraulic unit. Passing through a cylindrical annular throttling channel 133, the working fluid experiences resistance to its movement, since the gradient forces of the magnetic field counteract the force of the shear flow arising from the pressure drop across the magnetorheological throttle. At the same time, by adjusting the magnitude of the current supplying the magnetic field inductor 129 within the proportional portion of the magnetization curve of the working fluid — magnetorheological slurry 126, it is possible to control the resistance to the flow of fluid and thereby its flow rate through the magnetorheological choke or pressure drop across it. When the working fluid flows along the axis of the annular throttling channel as a result of the presence of a magnetic circuit on the cylindrical pole spacer 131 or pole washer 132, forming a cylindrical annular throttling channel 133, teeth 134 (magnetic field concentrators), a number of zones with an increased magnetic field gradient appear. In addition, due to the gradient forces, the magnetic field between the teeth is curved. Due to the presence of teeth in the annular gap, gradient magnetic field forces are created, which allow more effective, that is, less energy, impact on the ferromagnetic particles of the magnetorheological suspension 126. The dents of the teeth 134 are filled with diamagnetic material, which prevents clogging of the depressions by ferromagnetic particles and ensures the preservation of a large range regulating the differential pressure on the magnetorheological throttle during its operation, i.e. increases the reliability of the coordinate table as a whole, increases the carrying capacity of hydrostatic guides of a cylindrical shape.

·

При внезапном возрастании давления или расхода на входе магнитореологического дросселя, например, при возникновении каких-либо неполадок в работе насосной станции 22, 23, 24 увеличивается мгновенное значение давления, которое воздействует на внутреннюю поверхность тонкостенной цилиндрической полюсной проставки 139. Вследствие расклинивающего воздействия со стороны рабочей жидкости происходит уменьшение величины цилиндрического кольцевого дросселирующего канала 133 и пропорциональное этому уменьшение расхода через магнитореологический дроссель. Кроме того, воздействие магнитного поля на рабочую жидкость при этом возрастает и, следовательно, расход через магнитореологический дроссель еще больше уменьшается, т.е. происходит стабилизация расхода через магнитореологический дроссель. Надежность магнитореологического дросселя, а следовательно, и координатного стола в целом повышается вследствие стабилизации расходных характеристик магнитореологического дросселя. Для расширения функциональных возможностей координатного стола и повышения его надежности в полюсной шайбе 141 (фиг.18) установлена перегородка 143 из ферромагнитного материала с упорами 144 из диамагнитного материала, а в тонкостенной цилиндрической полюсной проставке 139 из эластичного ферромагнитного материала - перегородка 142 из ферромагнитного материала, что позволяет при изменении тока в индукторе 129 магнитного поля тонкостенной центральной части полюсной цилиндрической проставки 139 изменять длину цилиндрического кольцевого дросселирующего канала 133 в направлении течения рабочей жидкости от минимального значения при нулевом токе до максимального при максимальном. При этом радиальные размеры цилиндрического кольцевого дросселирующего канала 133 не изменяются и подобраны таким образом, чтобы рабочая жидкость - магнитореологическая суспензия 126 при максимально возможном изменении тока в индукторе 129 находилась в насыщенном состоянии. Таким образом, возможно дополнительное увеличение диапазона регулирования перепада давления на магнитореологическом дросселе путем широкого изменения длины цилиндрического кольцевого дросселирующего канала 133:
ΔP_МРД(I) = P_н-P(I) =

· μ(I)·l(I)
При максимальном токе в индукторе 129 магнитного поля тонкостенная цилиндрическая полюсная проставка 139 с установленной в ней перегородкой 142 прижимается к упорам 144 из диамагнитного материала, установленным на перегородке 143. Установка упоров 144 из диамагнитного материала позволяет избежать соприкосновения отдельных частей магнитопровода и замыкания всего магнитного потока только через перегородку 143 полюсной шайбы 141 и перегородку 142, установленную в торцовой части тонкостенной цилиндрической полюсной проставки 139 (т.е. минуя цилиндрический кольцевой дросселирующий канал 133). Замыкание магнитного потока приводит к прекращению какого-либо регулирования перепада давления на магнитореологическом дросселе и тем самым к снижению надежности магнитореологического дросселя, а следовательно, и координатного стола в целом. Увеличение диапазона регулирования магнитореологического дросселя позволяет создать большую разность давлений в камерах 39-46 (фиг. 1,2,6) высокого давления гидростатических направляющих 4-7 цилиндрической формы, что позволяет повысить их грузоподъемность, т.е. вес перемещаемого объекта.To further expand the range of pressure regulation in high-pressure chambers, and therefore, increase the load capacity of cylindrical hydrostatic guides, the cylindrical pole spacer 139 (Fig. 17) of the magnetorheological throttle is made of thin-walled ferromagnetic elastic material. This allows you to change the magnitude of the cylindrical annular throttling channel 133 when changing the current in the magnetic field inductor 129 from the maximum value at zero current to the minimum at maximum current. The elasticity of the pole cylindrical spacer 139 is selected so that when the maximum possible change in current in the inductor 129 of the magnetic field, the working fluid — magnetorheological suspension 126 is in a state close to magnetic saturation. Thus, it is possible to further increase the control range of the differential pressure across the magnetorheological throttle at a constant flow rate through it through a wide change in the value of the cylindrical annular throttling channel 133:
ΔP _mrd (I) = P _n -P (I) =

·

With a sudden increase in pressure or flow rate at the inlet of the magnetorheological throttle, for example, if there are any malfunctions in the operation of the pump station 22, 23, 24, the instantaneous pressure increases, which affects the inner surface of the thin-walled cylindrical pole spacer 139. Due to the wedging effect from the working of liquid there is a decrease in the value of the cylindrical annular throttling channel 133 and a proportional decrease in flow through magnetorheological throttle. In addition, the effect of the magnetic field on the working fluid increases in this case and, therefore, the flow rate through the magnetorheological throttle is further reduced, i.e. there is a stabilization of flow through the magnetorheological throttle. The reliability of the magnetorheological choke, and therefore the coordinate table as a whole, is enhanced due to the stabilization of the flow characteristics of the magnetorheological choke. To expand the functionality of the coordinate table and increase its reliability, a partition plate 143 of ferromagnetic material with stops 144 of diamagnetic material is installed in the pole washer 141 (Fig. 18), and a partition 142 of ferromagnetic material is installed in the thin-walled cylindrical pole spacer 139 of elastic ferromagnetic material, which allows you to change the length of the cylindrical ring chokes when changing the current in the magnetic field inductor 129 of the thin-walled central part of the pole cylindrical spacer 139 channel 133 in the direction of flow of the working fluid from the minimum value at zero current to the maximum at maximum. In this case, the radial dimensions of the cylindrical annular throttling channel 133 do not change and are selected so that the working fluid is magnetorheological suspension 126 at the maximum possible change in current in the inductor 129 was in a saturated state. Thus, it is possible to further increase the control range of the differential pressure across the magnetorheological throttle by a wide change in the length of the cylindrical annular throttling channel 133:
ΔP _MRD (I) = P _n -P (I) =

Μ (I) l (I)
At the maximum current in the magnetic field inductor 129, a thin-walled cylindrical pole spacer 139 with a septum 142 installed in it is pressed against the stops 144 of diamagnetic material mounted on the partition 143. The installation of the stops 144 of diamagnetic material allows you to avoid contact of individual parts of the magnetic circuit and short circuit of the entire magnetic flux through the partition 143 of the pole washer 141 and the partition 142 installed in the end part of the thin-walled cylindrical pole spacer 139 (i.e., bypassing the cylinder throttle ring throttle channel 133). The closure of the magnetic flux leads to the cessation of any regulation of the pressure drop across the magnetorheological throttle, and thereby to a decrease in the reliability of the magnetorheological throttle, and, consequently, to the coordinate table as a whole. The increase in the control range of the magnetorheological throttle allows you to create a large pressure difference in the chambers 39-46 (Fig. 1,2,6) of high pressure hydrostatic guides 4-7 of a cylindrical shape, which allows to increase their load capacity, i.e. weight of the moved object.

Claims (8)

 1. COORDINATE TABLE containing upper and lower carriages, a fixed base on which the lower carriage is mounted on two hydrostatic guides with sealing elements, the upper carriage is mounted on the lower carriage with the ability to move on two hydrostatic guides with sealing elements in the direction perpendicular to the direction of movement of the lower carriages, drives of upper and lower carriages with hydraulic cylinders in housings with sealing elements and with distributors for connection with us with a station, a control unit and a table position measuring device, characterized in that the hydrostatic guides of the upper and lower carriages are cylindrical in shape, each of the cylindrical guides is provided with two hydrostatic supports, each of which is made in the form of four high pressure chambers and low pressure chambers, moreover, two high-pressure chambers are located in a plane perpendicular to the surface of the fixed base, the other two high-pressure chambers are placed in the plane, steam the surface of the fixed base, and the low-pressure chambers are located around each high-pressure chamber, while each high-pressure chamber is equipped with a magnetorheological choke at the inlet for connection with the pump station.  2. The table according to claim 1, characterized in that each sealing element of a hydrostatic guide of cylindrical shape is made in the form of an elastic thin-walled shell in the form of a body of revolution, mounted with the possibility of rolling between the hydrostatic guide and the corresponding carriage.  3. The table according to claims 1 and 2, characterized in that the hydraulic cylinder of the drive of each carriage is made in the form of two hydraulic motors with pushers mounted coaxially on two opposite sides of the carriage, and the sealing element of the body of the hydraulic motor of each carriage is made in the form of an elastic thin-walled shell in the form of a body rotation installed with the possibility of rolling between the pusher and the inner wall of the housing, and the drive distributor of each carriage is made in the form of four magnetorheological chokes, included in m Stow scheme.  4. The table according to claims 1 to 3, characterized in that the two hydraulic motors of the upper carriage drive are equipped with two pairs of hydraulic transmission units in housings with sealing elements for hydraulic connection with the distributor and the pump station, and the hydrostatic guides of the cylindrical shape of the upper carriage are equipped with two pairs of hydraulic transmission nodes in housings with sealing elements for hydraulic connection with the pumping station, made in the form of hollow pushers located coaxially in a plane parallel to board the movement of the lower carriage, while the sealing elements of the bodies of the hydraulic transmission units are made in the form of thin-walled shells in the form of bodies of revolution installed with the possibility of rolling between hollow pushers and the inner walls of the bodies of the hydraulic transmission units.  5. The table according to claims 1 to 4, characterized in that each magnetorheological choke is made in the form of a magnetic field inductor and magnetic circuit installed to ensure coverage of the inductor and made in the form of a glass, a pole cylindrical spacer and a pole washer, placed with the formation of a cylindrical throttling channel moreover, on the surface of at least one of the pole elements of the magnetic circuit, trapezoidal teeth are made, in the hollows between which there is a layer of diamagnetic material.  6. The table according to claims 1 to 5, characterized in that the thin-walled shell in the form of a body of revolution of each sealing element is reinforced, for example, with fiberglass threads in the longitudinal direction.  7. The table according to claims 1 to 6, characterized in that the pole cylindrical spacer of the magnetic circuit of each magnetorheological inductor is made of thin-walled ferromagnetic elastic material.  8. The table according to claims 1 to 7, characterized in that the pole washer of the magnetic circuit of each magnetorheological throttle is equipped with a baffle installed inside it with channels for draining the working fluid and stops of diamagnetic material, and the pole cylindrical spacer of the magnetic circuit is equipped with a ferromagnetic baffle on the side of the pole washer material and installed with the possibility of axial movement.

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