JPH11190306A - Air slide device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high thrust at a low cost by providing a fixed member having a linear guide surface, a slide table capable of reciprocating along the guide surface by a hydrostatic bearing, and the first and second air pressure chambers arranged in the reciprocating direction, and controlling the air pressure to impart a thrust to the table by the pressure difference between the pressure chambers. SOLUTION: A slide table 10 is supported in no contact on a horizontal fixed member 1 by a hydrostatic bearing 20, and the air pressure of an air pressure chamber 30 between the fixed member 1 and the table 10 is variably controlled by an air pressure control system. When the air pressures of first and second air chambers 31, 32 partitioned by a partitioning plate 3 are equal to each other, the table 10 is rested on the fixed member 1, and when the solenoid valve of the pressure chamber 31 is opened to reduce the air pressure of the pressure chamber 31, a thrust for moving the table to right by the air pressure difference between the pressure chambers 31, 32 acts on the table 10. The movement of the table 10 is performed in non-contact state to the fixed member 1 and also by the same thrust as by an air cylinder, a high thrust can be provided at a low cost with excellent flexibility.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air slide device used in a semiconductor manufacturing technology field, a precision product shape measurement technology field, and the like.

[0002]

2. Description of the Related Art An air slide device used as a high-precision positioning device, a transfer device, or a position adjustment device in a semiconductor manufacturing field, a liquid crystal manufacturing field, or the like is a slide table that reciprocates horizontally in front, rear, left, and right directions, or a vertical slide table. A vertically moving slide table is held in a non-contact manner by an air static pressure bearing on a fixed member that also serves as a guide, and the slide table is moved back and forth, right and left by a linear motor or ball screw, or up and down. Widespread.

In the conventional air slide device shown in FIG. 12, a slide table 70 is moved in a horizontal direction by a linear motor 71 which is an actuator of an air static pressure bearing. The slide table 70 includes a horizontal upper plate 70a and side plates 70b fixed to both lower surfaces thereof.
And the inner peripheral surfaces of the upper plate 70a and the side plate 70b are fitted to both ends of the guide rail 72 as a fixing member, and the static pressure bearing 74 is constituted by the static pressure air supply nozzle 73 provided on the inner peripheral surface. doing. The linear motor 71 includes a coil 71a fixed to the center of the guide rail 72 and a permanent magnet 71b fixed to the center of the lower surface of the upper plate 70a. The slide table 70 supported in a non-contact manner moves in the horizontal direction along the guide rail 72.

The conventional air slide device shown in FIG. 13 holds a Z-axis table 80, which is a slide table, on a vertical guide rail 81 by means of a hydrostatic bearing (not shown) so as to be vertically movable. It is moved up and down by a ball screw 82. The ball screw 82 is screwed onto the Z-axis table 80 and driven by a forward / reverse rotation motor 83. It should be noted that a reduction gear and an electromagnetic brake (not shown) for preventing the natural fall of the Z-axis table 80 are also used in this type of air slide device.

[0005]

In the air slide device shown in FIG. 12, the slide table is supported by a static pressure bearing and driven in a non-contact manner by a linear motor as an actuator of the air static pressure bearing. Although the table can be moved, the entire apparatus becomes expensive because a linear motor is used as the table drive source. Further, the linear motor has a low thrust because the magnetic gap between the permanent magnet and the coil core is as large as about 6 mm, and is not suitable for a slide table to which a large addition is applied.

In the air slide apparatus shown in FIG. 13, the load applied to the Z-axis table directly acts on the ball screw and acts as a moment load on the guide rail, so that a large load is moved up and down, although not as much as a linear motor. Is difficult, and the moment load applied to the guide rail shortens the life of the table.

It is an object of the present invention to provide a long-life air slide device in which a slide table supported by a hydrostatic bearing is moved horizontally or vertically by a low-cost, high-thrust actuator.

[0008]

The technical means for achieving the above object of the present invention is a non-contact support which can reciprocate along the guide surface by a fixed member having a linear guide surface and a hydrostatic bearing. A slide table, first and second air pressure chambers arranged in the direction of the reciprocal movement, and an air pressure control system for variably controlling the air pressure of the air pressure chamber. And a thrust is applied to the slide table by an air pressure difference of the second air pressure chamber.

Here, the fixing member is a horizontal guide rail that supports the slide table so as to be movable in the front-rear and left-right directions, or a vertical guide rail that supports the slide table so as to be movable in the vertical direction. is there. At least one of the fixed member and the slide table is provided with an air supply nozzle for supplying static air forming a static pressure bearing, and the slide table is movably supported by the fixed member in a non-contact manner. In this case, the air pressure chamber corresponds to the cylinder chamber of the air cylinder, and the slide table corresponds to the piston of the air cylinder, so that a large thrust (driving force) by the air pressure can be applied to the slide table. As described above, the present invention eliminates the linear motor used as the driving means of the conventional air slide apparatus of this type, and employs a driving source using air.
The point that the slide table moves while being supported in a non-contact manner by the hydrostatic bearing is the same as the conventional one.However, large thrust is obtained by using the air drive for both drive and support, and high accuracy and durability An inexpensive air slide device has been realized.

According to a second aspect of the present invention, an exhaust hole for avoiding mutual interference between the air of the static pressure bearing and the air of the air pressure chamber is provided at a boundary between the static pressure bearing and the air pressure chamber between the fixed member and the slide table. It is provided to maintain the functions of the static pressure bearing and the air pressure chamber.

According to a third aspect of the present invention, the first air pressure chamber and the second
By supplying high-pressure air to one of the air pressure chambers or exhausting one of the first air pressure chamber and the second air pressure chamber,
A thrust is applied to the slide table.
In this case, an air supply nozzle and an exhaust nozzle are connected to both the first air pressure chamber and the second air pressure chamber, so that the above air supply and exhaust operation is performed smoothly.

According to a fourth aspect of the present invention, the fixing member has a horizontal magnetic substrate and a partition plate fixed on the substrate, and the slide table has a hollow box shape with an opening at a lower surface.
An air pressure chamber divided into a first air pressure chamber and a second air pressure chamber by the partition plate is formed in the internal space by housing the partition plate in the internal space of the slide table. I do. In this case, the partition plate of the fixing member can exhibit not only a partition function of bisecting the air pressure chamber but also a guide function at the time of horizontal movement of the slide table. Further, by forming a hydrostatic bearing between the end surface of the partition plate and the inner wall surface of the slide table, the movement of the slide table is made smoother and more stable. Become.

According to a sixth aspect of the present invention, the fixed member has a vertical guide member, and a static pressure bearing and first and second air pressure chambers are formed between the guide member and the slide table, thereby forming the slide table. It is characterized by moving vertically along the guide member. When the slide table is moved up and down in this way, as in the invention of claim 7, between the fixed member and the vertically movable slide table,
It is desirable to install an air static pressure slide bearing that absorbs the impact of the slide table drop.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Each embodiment will be described in order with reference to FIGS. FIGS. 1 to 9 show an embodiment of an air slide device having a horizontal slide structure.
FIGS. 0 and 11 show an embodiment of an air slide device having a vertical slide structure. In each of the embodiments, functionally identical portions are denoted by the same reference numerals.

In the air slide apparatus of the first embodiment shown in FIGS. 1 to 4, a slide table 10 is supported on a horizontal fixed member 1 by a static pressure bearing 20 in a non-contact manner. Air pressure chamber 30 formed between
Is variably controlled by the air pressure control system 40 to reciprocate the slide table 10 in the horizontal direction (the left and right direction in FIG. 1) along the fixed member 1.

The fixing member 1 has a stationary, for example, horizontal magnetic substrate 2 and a partition plate 3 fixed to the center of the upper surface of the substrate 2. The slide table 10 is a rectangular hollow box having an opening on the lower surface, that is, the surface facing the substrate 2.
As shown in (1), when the slide table 10 is put on the substrate 2, the partition plate 3 is accommodated in the internal space of the slide table 10. At a plurality of locations on the lower surface of the slide table 10, air supply ports of static pressure air supply nozzles 21 are formed, from which static pressure air is jetted toward the upper surface of the substrate 2, so that the slide table 10 does not contact the substrate 2. The supporting hydrostatic bearing 20 is formed. A permanent magnet 22 is embedded on the lower surface of the slide table 10. The permanent magnet 22 balances the attraction force for magnetically attracting the magnetic substrate 2 and the repulsive force of the hydrostatic bearing 20 on the slide table 10. 10 is kept in a stable non-contact state.

An air pressure chamber 30 is formed by the internal space of the slide table 10 supported on the substrate 2 in a non-contact manner and the substrate 2, and the air pressure chamber 30 is divided by the partition plate 3 into a first air pressure chamber 31.
And the second air pressure chamber 32. Both end surfaces of the partition plate 3 are used as guide surfaces when the slide table 10 moves horizontally on the substrate 2. On both end faces of the partition plate 3, static pressure air supply nozzles 23 are formed as shown partially by broken lines in FIG.
The static pressure bearing 24 is formed by ejecting the static pressure air toward the inner wall surface. At the tip of the nozzle 23 of the partition plate 3, FIG.
As shown in FIG. 1, a radial shallow groove is provided to evenly supply static pressure air to the inner wall surface of the slide table 10. This is the same for the nozzle 21 on the lower surface of the slide table 10 (see FIG. 1). Air supply to the nozzles 23 of the partition plate 3 is performed by a hose 25 connected to the substrate 2, and air supply to the nozzles 21 of the slide table 10 is performed by a hose 26 connected to the slide table 10.

First air pressure chamber 3 partitioned by partition plate 3
Supply and exhaust to the first and second air pressure chambers 32 are performed by first and second supply hoses 41 and 42 and first and second exhaust hoses 4 connected to both right and left ends of the slide table 10.
It is performed at 3, 44. Each of the exhaust hoses 43 and 44 is provided with, for example, a solenoid valve 45 or 46 for adjusting the air flow rate. Air pressure control system 4 using each of these hoses
No. 0 moves the slide table 10 supported on the fixed member 1 in a non-contact manner by a static pressure bearing in the horizontal direction as follows.

When the first and second air pressure chambers 31 and 32 have the same air pressure, the slide table 10 is supported on the fixed member 1 in a non-contact manner and is stationary. When the slide table 10 is moved from this state, for example, to the right in FIG. 2, the solenoid valve 45 of the first exhaust hose 43 connected to the first pressure chamber 31 is opened to lower the air pressure in the first air pressure chamber 31. . Then, a thrust for moving the slide table 10 rightward in FIG. 2 acts on the slide table 10 due to an air pressure difference between the two air pressure chambers 31 and 32. Alternatively, a thrust for moving the slide table 10 rightward in FIG. 2 can be generated by supplying high-pressure air from the second supply hose 42 to the second air pressure chamber 32 and increasing the air pressure.

The movement of the slide table 10 as described above is performed in a non-contact state with the fixed member 1 and with the same thrust as the air cylinder, so that a high thrust can be obtained. Therefore, this air slide device can be applied even when handling a large load. Such a position detection during the movement of the slide table 10 can be performed in a non-contact and highly accurate manner by installing a linear scale or a laser measuring device (not shown) in the movement direction.
Then, by feeding back the detected position signal to the drive system, precise positioning can be performed.

The maximum moving distance of the slide table 10 is determined by the width of the partition plate 3 having the hydrostatic bearing function in the left-right direction in FIG. 1 and the width of the internal space of the slide table 10.
Although such a table maximum movement distance cannot be increased as compared with the third embodiment of FIG. 7 described later due to the restriction of the movement accuracy, in a table that moves in a relatively small range such as a positioning table of a bonding machine for semiconductor manufacturing. Is no problem.

The air slide device of the second embodiment shown in FIGS. 5 and 6 is a means for avoiding the interference of air between the static pressure bearings 20 and 24 of the first embodiment and the air pressure chamber 30. And exhaust holes 27 and 28 are provided. For example, the exhaust hole 27 opened on the lower surface of the slide table 10
Is formed at an appropriate position between the air supply port of the nozzle 21 and the air pressure chamber 30, and the air supplied from the nozzle 21 and the air pressure chamber 3 are formed.
The high-pressure air from 0 is exhausted from the intermediate exhaust hole 27 so that they do not interfere with each other. As a result, the air pressure states of the static pressure bearing 20 and the air pressure chamber 30 are properly maintained without interference from each other, and the performance of the air slide device is stabilized. For the same purpose, a pair of exhaust holes 28 opened on both end surfaces of the partition plate 3 are formed on both sides of the nozzle 23 so as to avoid interference between the air supplied from the air supply nozzle 23 and the air in the air pressure chamber 30. Let it. Thereby, the air pressure state of the static pressure bearing 24 and the air pressure state of the air pressure chamber 30 are properly maintained without interference with each other, and the performance of the air slide device is stabilized.

The air slide apparatus according to the third embodiment shown in FIGS. 7 to 9 has a pair of guide plates 2 parallel to the moving direction of the slide table 10 on both sides of the upper surface of the substrate 2 of the horizontal fixing member 1.
9, the slide table 10 is moved between the pair of guide plates 29. In this case, the partition plate 3 is used only to divide the air pressure chamber 30 between the slide table 10 and the substrate 2 into two. The hydrostatic bearing 20 is constituted by the nozzle 21 formed on the lower surface of the slide table 10 and the substrate 2, and the nozzle 21 ′ formed on the outer surface of the side wall of the slide table 10 facing the guide plate 29.
And the guide plate 29 constitute a hydrostatic bearing 24 '.

In the air slide apparatus according to the fourth embodiment shown in FIG. 10, a slide table 110 is non-contactly supported on a vertically arranged fixing member 101 by a static pressure bearing 120.
The air pressure in an air pressure chamber 130 formed between the slide table 110 and the slide table 110 is variably controlled by an air pressure control system 140 to reciprocate the slide table 110 in the vertical direction. The fixing member 101 in this case has a vertical casing 103 having a bottom plate 102, and the lower portion of the slide table 110 is inserted into the casing 103, and the casing 1
A static pressure bearing 120 is formed by a static pressure air supply nozzle 121 provided on the inner wall surface of the slide table 03 and a side surface of the slide table 110. The air pressure chamber 130 is provided on the slide table 11.
The first air pressure chamber 13 is formed by a flange 104 extending from the first air pressure chamber 13.
The first and second air pressure chambers 132 are vertically divided into two. An air supply hose 141, 142 and an exhaust hose 143, 144 are connected to the first and second air pressure chambers 131, 132, respectively, and the exhaust hoses 143, 144 are connected to the solenoid valve 14 respectively.
5,146.

The air pressure in the upper and lower air pressure chambers 131 and 132 is controlled by the air pressure control system 140 so that the slide table 110 can be stopped and moved up and down. When the slide table 110 is stationary, the air pressures of the upper and lower air pressure chambers 131 and 132 are controlled so as to correct its own weight and load. The vertical movement of the slide table 110 is performed by controlling the opening and closing of the solenoid valves 145 and 146 or by controlling the air supply air pressure from the air supply hoses 141 and 142. Such vertical movement of the slide table 110 can be performed with high accuracy because it is inexpensive because air pressure is used, and high thrust is obtained, and is performed in a non-contact support state by the hydrostatic bearing 120. Further, the position of the vertical movement of the slide table 110 can be detected by the linear scale 50 fixed to the slide table 110 in the vertical direction and the measurement head 51 fixed to the casing 103, and the detection signal is fed back to the drive system to achieve precision. Positioning is possible.

In the vertically moving slide table 110, the difference in air pressure between the upper and lower air pressure chambers 131 and 132 may become excessive due to the relationship between the weight of the slide table 110 and the applied load. In such a case, an exhaust hole 52 may be formed in the casing 103 between the upper and lower air pressure chambers 131 and 132 to prevent air from flowing from one air pressure chamber to the other air pressure chamber. .

In addition, since a large load is applied to the slide table 110, the downward movement thereof is likely to be unstable, and a sudden descent tends to cause an impact, so that FIG. Casing 1 as shown
It is preferable that the hydrostatic thrust bearing 60 be constituted by a space provided between the bottom plate 102 of FIG. The hydrostatic thrust bearing 60 is
A static pressure air supply nozzle 61 and an exhaust nozzle 62.

The air slide device of the fifth embodiment shown in FIG. 11 is adapted to the case where the weight of the slide table 110 of FIG. The slide table 110 is moved upward simply by increasing the air pressure in the air pressure chamber 130 '. In such an air slide device, the slide table 11
Hydrostatic thrust bearing 60 'for absorbing shock when moving up and down 0
And the slide table 110
It is desirable to install between these flanges.

[0029]

According to the present invention, the slide table supported on the fixed member by the hydrostatic bearing is slid by the air pressure control of the air pressure chamber formed between the slide table and the fixed member. Because it can move with high precision and can obtain high thrust by air pressure drive similar to an air cylinder,
An inexpensive and versatile air slide device that can sufficiently cope with an increase in the weight and load of the slide table can be provided.

Further, by providing the static pressure bearing between the fixed member and the slide table with an exhaust hole for avoiding the interference between the air and the air pressure chamber, the function of the static pressure bearing and the air pressure difference is stabilized and the slide table is provided. High-precision movement and its control are facilitated.

When a static pressure thrust bearing is installed in an air slide device for moving the slide table up and down, even if the weight of the slide table or the load increases, the shock at the time of movement of the slide table is absorbed by the static pressure thrust bearing. A stable movement of the slide table and a highly reliable air slide device can be provided.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing an air slide device according to a first embodiment of the present invention.

FIG. 2 is a front view including a partial cross section of the apparatus in FIG. 1;

FIG. 3 is a sectional view taken along the line AA of FIG. 2;

FIG. 4 is an exploded front view of the apparatus shown in FIG. 1 during assembly.

FIG. 5 is a partial sectional view of an air slide device according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view along the line BB in FIG. 5;

FIG. 7 is a plan view schematically showing an air slide device according to a third embodiment of the present invention.

FIG. 8 is a sectional view taken along the line CC of FIG. 7;

FIG. 9 is a sectional view taken along the line DD in FIG. 9;

FIG. 10 is a front view schematically showing an air slide device according to a fourth embodiment of the present invention.

FIG. 11 is a front view schematically showing an air slide device according to a fifth embodiment of the present invention.

FIG. 12 is a plan view schematically showing a conventional air slide device.

FIG. 13 is a side view schematically showing another conventional air slide device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 101 Fixed member 20, 120 Static pressure bearing 30 Air pressure chamber 31 First air pressure chamber 32 Second air pressure chamber 40, 140 Air pressure control system 60 Static pressure thrust bearing

Claims (7)

[Claims] 1. A fixed member having a linear guide surface, a slide table supported by a static pressure bearing so as to be reciprocally movable along the guide surface, and a first table arranged in the direction of the reciprocal movement. And a second air pressure chamber, and an air pressure control system for variably controlling the air pressure in the air pressure chamber, and applying a thrust to the slide table by the difference in air pressure between the first and second air pressure chambers. An air slide device, characterized in that: 2. An exhaust hole for avoiding mutual interference between the air of the static pressure bearing and the air of the air pressure chamber is provided at a boundary between the static pressure bearing and the air pressure chamber between the fixed member and the slide table. The air slide device according to claim 1, wherein 3. A slide table by supplying high-pressure air to one of the first air pressure chamber and the second air pressure chamber or exhausting one of the first air pressure chamber and the second air pressure chamber. 3. The air slide device according to claim 1, wherein a thrust is applied to the air slide device. 4. The fixing member has a horizontal magnetic substrate and a partition plate fixed on the substrate, and the slide table has a hollow box shape with an opening at a lower surface, and is provided in an internal space of the slide table. An air pressure chamber divided into a first air pressure chamber and a second air pressure chamber by the partition plate by accommodating the partition plate is formed in the internal space. 3. An air slide device. 5. The air slide device according to claim 4, wherein a hydrostatic bearing is formed between an end surface of the partition plate and an inner wall surface of the slide table facing each other. 6. The fixing member has a vertical guide member, a static pressure bearing and first and second air pressure chambers are formed between the guide member and the slide table, and the slide table is moved along the guide member. 4. The air slide device according to claim 1, wherein the air slide device is moved vertically. 7. The air slide device according to claim 6, wherein a static pressure thrust bearing for absorbing an impact due to a drop of the slide table is provided between the fixed member and the slide table.