JP2001271878A - Positioning device for vibration control base - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost positioning device for a vibration control base, capable of accurately controlling the height position of a vibration control table, without needing a sensor in the vibration control base having a fixed base, the vibration control table supported in a moving direction determined state to the fixed base; an air pressure holding mechanism formed between the fixed base and the vibration control table to advance/retreat the vibration control table relative to the fixed base by the force of compressed air; and a compressed air source for supplying compressed air to the air pressure holding mechanism. SOLUTION: This positioning device for the vibration control base is provided with a regulator installed between the air pressure holding mechanism and the compressed air source with the capability of regulating the pressure of the compressed air supplied to the air pressure-holding mechanism, in order to control the pressure of compressed air supplied to the air pressure holding mechanism; a pressure-regulating member provided in a position adjustable manner inside the regulator and charging the pressure of the compressed air supplied from the regulator to the air pressure holding mechanism, by its movement; and a pressure-regulating member moving mechanism provided between the pressure-regulating member and the vibration control table to move the pressure-regulating member by the movement of the vibration control table in a determined direction to the fixed base.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration table, and more particularly to an apparatus for positioning a vibration-isolating table.

[0002]

[Prior art and its problems] As one type of anti-vibration table,
In general, the anti-vibration table is supported so as to be movable in the vertical direction with respect to the fixed base, and the anti-vibration table is moved between the fixed base and the anti-vibration table by the force of compressed air. There is known a type provided with an air pressure holding mechanism for moving forward and backward. The pneumatic holding mechanism is formed by, for example, a rolling diaphragm.

Conventionally, in this vibration isolating table, the height position of the vibration isolating table is detected using various sensors, and the supply air pressure to the air pressure holding mechanism is controlled in accordance with the detection result.
The height position of the vibration isolation table was controlled within a certain range. However, an apparatus using a sensor requires a precise sensor and its feedback system when attempting to precisely control the height position of the vibration isolation table, and is inevitably expensive.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an inexpensive vibration-isolation table positioning apparatus which can precisely control the height position of an anti-vibration table without requiring a sensor.

[0005]

SUMMARY OF THE INVENTION A positioning device for a vibration isolating table according to the present invention includes a fixed base; a vibration isolating table supported in a fixed direction with respect to the fixed base; An air pressure holding mechanism for moving the vibration isolating table back and forth with respect to the fixed base by the force of the compressed air; a compressed air source for supplying compressed air to the air pressure holding mechanism; A regulator that is capable of adjusting the pressure of compressed air supplied to the air pressure holding mechanism; a pressure adjusting member that is provided in the regulator so as to be adjustable in position and that changes the pressure of compressed air supplied from the regulator to the air pressure holding mechanism by movement thereof; A pressure adjusting member moving mechanism that is provided between the pressure adjusting member and the vibration isolation table and moves the pressure adjustment member by moving the vibration isolation table in a predetermined direction with respect to the fixed base. It is characterized in that was. According to this configuration, since the pressure adjusting member in the regulator is moved by the movement of the anti-vibration table, the position of the anti-vibration table can be stabilized without requiring a complicated sensor or feedback system.

It is desirable that the pressure adjusting member moving mechanism does not transmit the vibration of the regulator in a direction other than the moving direction of the vibration isolating table to the vibration isolating table. Thereby, the positional accuracy of the vibration isolation table can be increased.

As a configuration for preventing the vibration of the regulator from being transmitted to the vibration isolating table, for example, the pressure regulating member can be moved along the moving direction of the vibration isolating table with respect to the fixed base. The slide shaft extends parallel to the direction of movement of the vibration isolating table, and has one end connected to the pressure regulating member and the other end abutting on the vibration isolating table, and penetrating through the inside and outside of the housing of the regulator. And a guide hole having a diameter larger than that of the slide shaft, which is inserted movably in the axial direction. When compressed air is being supplied to the regulator by the compressed air source, air is discharged from the gap between the slide shaft and the guide hole to the outside of the regulator, and the slide shaft and the guide hole are kept out of contact with the air. By connecting the pressure-adjusting member and the vibration isolating table with a slide shaft supported with an air bearing in between, a movement of the vibration isolating table in a predetermined direction with respect to the fixed base is slid. The pressure regulating member can be moved sensitively with almost no dynamic resistance. On the other hand, since the slide shaft and the housing of the regulator are not directly in contact with each other, the vibration on the regulator side can be hardly transmitted to the vibration isolating table via the slide shaft.

In the pressure adjusting member moving mechanism, the vibration isolating table further has a contact surface with a slide shaft orthogonal to the moving direction, and the slide shaft abuts on the contact surface of the vibration isolating table. It is desirable to have a spherical contact portion in contact. According to this configuration, since the contact area between the anti-vibration table and the slide shaft is minimized, excess vibration on the regulator side is not easily transmitted to the anti-vibration table, but the pressing force by the anti-vibration table is reliably applied to the slide shaft. Can be transmitted.

In the positioning apparatus for a vibration isolating table according to the present invention, the regulator includes: a primary pressure inlet connected to the compressed air source so as to allow air flow; a secondary pressure chamber connected to the air pressure holding mechanism and air flow. A main valve for opening and closing between the primary pressure inlet and the secondary pressure chamber; a pilot chamber having a bleed hole through which compressed air in the secondary pressure chamber can flow and communicating with the outside; a secondary pressure chamber and a pilot pressure chamber The main valve is opened when moving to the secondary pressure chamber side,
A floating piston that closes the main valve when moving to the pilot pressure chamber side; air that flows from the secondary pressure chamber to the outside when the floating piston moves to the pilot pressure chamber side and the main valve is closed; A pressure regulating member is interposed between the pilot valve and a slide shaft to control the introduction of air from the secondary pressure chamber to the pilot pressure chamber; It is preferable to provide a measuring capsule that expands and contracts according to the pressure of the pressure chamber to open and close the pilot valve. In this configuration, the pilot valve moves in accordance with the movement of the vibration isolating table, and the degree of opening changes. As a result, the opening / closing timing of the main valve changes, and the pressure of the compressed air taken out from the secondary pressure chamber is prevented. It can be adjusted according to the position of the swing table.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, an anti-vibration table 10 formed in a plane rectangular shape is supported on a fixed base 20 so as to be movable vertically (up and down).
A set of a pneumatic holding mechanism 30 and a regulator 40 is provided at each of the four corners between the zero and the fixed base 20.

Each of the pneumatic holding mechanisms 30 includes an upper body 3
1 and a lower body 32, a peripheral portion of a rolling diaphragm 33 is sandwiched and held between the upper body 31 and the lower body 32, and the rolling diaphragm 33 is
The variable volume pressure chamber 34 is formed in the lower part of. A block 11 that extends into the upper body 31 and contacts the rolling diaphragm 33 is fixed to the lower surface of the vibration isolation table 10, and the vibration isolation table 10 moves up and down according to the pressure in the variable volume pressure chamber 34. At the upper end of the upper body 31, when the pressure in the variable volume pressure chamber 34 is equal to or less than a predetermined value,
Receiving surface 35 that is in contact with and supports the lower surface of vibration isolation table 10
Are formed.

Referring to FIGS. 2 and 3, details of the regulator 40 which is set with each of the air pressure holding mechanisms 30 will be described. A box-shaped holding frame 21 for fixing each regulator 40 is fixed to the fixed base 20, and an opening 22 is formed in an upper portion of the holding frame 21. Regulator 40
Are, in order from the top in FIG. 3, reference numerals 41a, 41b, 41c,
It has a housing 41 made of four members attached with 41d,
A cylindrical insertion portion 23 having an external thread formed on an outer peripheral surface is fixed to an upper portion of the uppermost housing 41a. The regulator 40 inserts the insertion portion 23 into the opening 22, and screws the lock nut 24 into the male screw of the insertion portion 23 protruding from the opening 22, so that the holding frame 21.
That is, it is fixed to the fixed base 20.

The lowermost housing 41 d of each regulator 40 has a primary pressure inlet 42 and a secondary pressure outlet 43.
Are formed, and a secondary pressure chamber 44 communicating with the secondary pressure outlet 43 is formed. The primary pressure inlet 42 is connected to a compressed air source 90 via an air flow passage 92 so as to allow air to flow therethrough, and the secondary pressure outlet 43 and the secondary pressure chamber 44 are connected to an air pressure holding mechanism via an air flow passage 93. It is connected to 30 variable volume pressure chambers 34 so that air can flow therethrough. A communication passage 46 between the primary pressure inlet 42 and the secondary pressure outlet 43 (secondary pressure chamber 44) is opened and closed by a main valve 47. 47 closes the communication passage 46.

The uppermost housing 41a and the housing 4
A control chamber 50 communicating with the secondary pressure chamber 44 via a communication passage 49 is formed between the control chambers 1b, and a measuring capsule (pressure regulating member) 51 is located in the control chamber 50. The measuring capsule 51 is a hollow container made of an elastic material, and changes its size in accordance with a pressure difference with the outside.

The housing 41a is provided with the above-described insertion portion 23.
Is formed integrally, and a slide shaft 52 is supported in a guide hole 45a formed in the shaft portion 45 so as to be vertically movable. The inner diameter of the guide hole 45a is slightly larger than the outer diameter of the slide shaft 52, and there is a slight gap between the guide hole 45a and the slide shaft 52. Compressed air source 9
When compressed air is supplied from 0 to the regulator 40, the air is discharged through this gap, and the slide pressure 52 is moved up and down without mechanical contact with the guide hole 45a by the discharged air pressure. . That is,
The slide shaft 52 is in a state of being slidably guided by the housing 41 via an air bearing.

A measuring capsule 51 is fixed to the lower end of the slide shaft 52, and the position of the measuring capsule 51 in the control room 50 changes as the slide shaft 52 moves up and down. Also, the slide shaft 5
At the upper end of 2, a contact protrusion 53 is provided which comes into contact with the regulator contact surface 10 a which is the lower surface of the vibration isolation table 10. The regulator contact surface 10a is formed as a plane orthogonal to the moving direction of the vibration isolating table 10 with respect to the fixed base 20, and the contact protrusion 53 on the slide shaft 52 side has a spherical end. Therefore, the contact protrusion 53
And the contact area of the regulator contact surface 10a of the vibration isolation table 10 is minimized.

A pilot diaphragm 63 and a control diaphragm 6 are provided between the housings 41b and 41c and between the housings 41c and 11d, respectively.
4 is sandwiched, and a pilot pressure chamber 65 is formed by the housing 41 b and the pilot diaphragm 63. A floating piston 61 is supported at the center of the pilot diaphragm 63 and the control diaphragm 64.

The pilot valve (pressure regulating member) 60 has its upper end in contact with the lower surface of the measuring capsule 51, and its lower end valve portion enters the pilot pressure chamber 65 through a communication passage 66 formed in the housing 41b. I'm coming. The pilot valve 60 is moved by a leaf spring 68 engaged near its upper end.
It is always pressed against the lower surface of the measuring capsule 51. The leaf spring 68 is fixed to the housing 11b by a fixing screw 69. From the above configuration, when the measuring capsule 51 expands and contracts, the pilot valve 60
Alternatively, when the measuring capsule 51 is moved up and down via the slide shaft 52, its vertical position changes.
Depending on the vertical position of the pilot valve 60, the communication path 66
, That is, the flow path area between the control chamber 50 and the pilot pressure chamber 65 changes. The pilot pressure chamber 65 communicates with the outside air through a bleed hole 70.

The floating piston 61 has a retainer plate 71 along a pilot diaphragm 63, a retainer plate 72 along a control diaphragm 64, a center block 73 sandwiched between these plates, and a balance weight 74. , An exhaust hole 75 opened to the secondary pressure chamber 44 side. The exhaust hole 75 is connected to the pilot diaphragm 63 and the control diaphragm 6 through a radial passage 76.
The relief chamber 77 communicates with the outside air through a relief hole 78. The opening end of the exhaust hole 75 to the secondary pressure chamber 44 is opened and closed by a relief valve 79. The relief valve 79 is integrated with the main valve 47 by a connecting shaft 79a. The upward movement of the integral member of the relief valve 79 and the main valve 47 is restricted when the main valve 47 closes the communication passage 46. When the floating piston 61 further moves upward toward the pilot pressure chamber 65 with respect to the relief valve 79 whose movement is restricted, the relief valve 79 opens the exhaust hole 75, and the secondary pressure chamber 44 , Radial passage 7
6. It is communicated with the outside air through the relief chamber 77 and the relief hole 78. That is, the relief valve 79 and the exhaust hole 75
The main valve 47 is connected to each air flow passage from
Constitutes an exhaust mechanism for discharging the air in the secondary pressure chamber 44 to the outside when is closed.

In the pilot diaphragm 63 and the control diaphragm 64, the pressure receiving area of the pilot diaphragm 63 is set larger than that of the pilot diaphragm 63. The floating piston 61 is urged by a compression spring 80 inserted between its upper surface and the housing 41b in a direction opposite to the direction in which the main valve 47 is urged by the compression spring 48. The force of the compression spring 80 is stronger than the force of the compression spring 48.

The apparatus having the above configuration operates as follows.
It is assumed that the air pressure holding mechanisms 30 and the regulators 40 at the four corners of the vibration isolation table 10 are adjusted to perform the same operation. First, a stable state in which no special external force is applied to the vibration isolation table 10 will be described.

Before the compressed air is supplied to the air pressure holding mechanism 30, the vibration isolating table 10 is supported in contact with the receiving surface 35. At this time, the force of the compression spring 80 is
, The main valve 47 opens the communication passage 46 via the floating piston 61 and the relief valve 79.

The compressed air from the compressed air source 90 is supplied to the primary pressure inlet 42 of the regulator 40 through the air flow passage 92.
, The primary pressure supplied to the primary pressure inlet 42 enters the secondary pressure chamber 44 through the communication passage 46, and the pressure in the secondary pressure chamber 44 increases. When the pressure in the secondary pressure chamber 44 exceeds a certain value, the floating piston 61 rises against the force of the compression spring 80. Then, the main valve 47 is raised by the force of the compression spring 48, and the communication area with the communication passage 46 is reduced, and the main valve 47 eventually closes the communication passage 46. When the floating piston 61 further rises, the relief valve 79 moves away from the exhaust hole 75 of the floating piston 61, and the air in the secondary pressure chamber 44 is discharged from the relief hole 78.

When the pressure in the secondary pressure chamber 44 increases, the pressure is applied to the control chamber 50 through the communication passage 49, and the measuring capsule 51 is moved by the pressure.
Shrinks. Then, the pilot valve 60 narrows or closes the flow area with the communication passage 66. Then pilot pressure chamber 6
5 communicates with the atmosphere through the bleed hole 70,
The pressure in the pilot pressure chamber 65 decreases and the pilot pressure chamber 6
Since the pressure difference between the pressure chamber 5 and the secondary pressure chamber 44 increases, the floating piston 61 further increases the tendency to ascend. Therefore, the main valve 47 closes the communication passage 46, and the pressure in the secondary pressure chamber 44 decreases.

When the pressure in the secondary pressure chamber 44 decreases, the floating piston 61 moves the relief valve 7 by the force of the compression spring 80.
Descend to the 9th side. Then, first, the exhaust hole 75 of the floating piston 61 is closed by the relief valve 79, and when the floating piston 61 further descends, the relief valve 79 and the main valve 4
7, the communication passage 46 is opened. Therefore, air flows again from the primary pressure inlet 42 to the secondary pressure chamber 44, and the pressure in the secondary pressure chamber 44 increases. The decrease in the pressure in the secondary pressure chamber 44 is also applied to the control chamber 50. As a result, the measuring capsule 51 expands, the pilot valve 60 opens, and the pressure in the pilot pressure chamber 65 also decreases. The speed is lower than that of the secondary pressure chamber 44, so that the floating piston 61 operates and drops in response to the pressure drop of the secondary pressure chamber 44, and opens the main valve 47. As a result of the above operations being continuously performed, when the compressed air source 90 is operated, the secondary pressure taken out from the secondary pressure outlet 43 is constant, and the constant pressure is set in the variable volume pressure chamber 34. The position of the anti-vibration table 10 is kept constant.

In the present apparatus, when the anti-vibration table 10 is moved up and down for some reason from the above stable state,
By changing the secondary pressure of the compressed air taken out from the secondary pressure outlet 43, the height position of the vibration isolation table 10 can be maintained so as not to move excessively. That is, when a force for vertically moving the vibration isolating table 10 is applied, the slide shaft 52 that makes the contact protrusion 53 contact the regulator contact surface 10a moves vertically, and the measuring capsule 51 in the control chamber 50 is moved. The vertical position of changes. When the vertical position of the measuring capsule 51 changes, the pilot valve 6
0 also moves up and down to change the opening degree, and as a result, the magnitude of the secondary pressure taken out from the secondary pressure outlet 43 is adjusted.

For example, when the anti-vibration table 10 is moved downward from the stable state, the measuring capsule 51 is moved via the slide shaft 52 which receives the downward moving force.
0, the pilot valve 60 which contacts the lower part of the measuring capsule 51 also moves downward,
The flow path area (opening degree) between 0 and the pilot pressure chamber 65 increases. Then, when the pressure in the secondary pressure chamber 44 rises,
The flow rate of the air supplied from the secondary pressure chamber 44 to the pilot pressure chamber 65 via the control chamber 50 increases (the timing at which the pilot valve 60 closes is delayed), and the secondary pressure chamber 44
And the pilot pressure chamber 65 hardly has a pressure difference. That is, the tendency of the floating piston 61 to move upward is suppressed, and unless the internal pressure of the secondary pressure chamber 44 becomes higher than the above-mentioned stable state, the main valve 47 closes and the relief valve 78 closes the secondary pressure chamber 44. Air is not exhausted. as a result,
The secondary pressure of the compressed air taken out from the secondary pressure outlet 43 of the regulator 40 increases, and accordingly, the pressure in the variable volume pressure chamber 34 increases, and the vibration isolation table 10 rises again. When the vibration isolating table 10 rises, the measuring capsule 51 moves upward, so that the opening degree of the pilot valve 60 returns to its original state, and the secondary pressure taken out from the secondary pressure outlet 43 also returns to its original state.

Conversely, from the above-mentioned stable state, the vibration isolating table 1
When 0 is moved upward, the load of the vibration isolating table 10 on the contact protrusion 53 is eliminated or reduced, so that the measuring capsule 51 is moved upward by the internal pressure of the control chamber 50, and the pilot valve 60 is also moved upward. To control room 5
The flow path area (opening) between the pressure chamber 0 and the pilot pressure chamber 65 is reduced. Then, when the pressure in the secondary pressure chamber 44 rises,
The flow rate of air supplied from the secondary pressure chamber 44 to the pilot pressure chamber 65 via the control chamber 50 is reduced (or the timing at which the pilot valve 60 closes is advanced), and the secondary pressure chamber 44 and the pilot pressure chamber 65 are closed. The pressure difference tends to increase. That is, the tendency of the floating piston 61 to move upward increases, and in a state where the internal pressure of the secondary pressure chamber 44 is lower than the above-mentioned stable state, the main valve 47 closes and the relief hole 78 is closed.
From the secondary pressure chamber 44 is discharged. as a result,
The pressure (secondary pressure) of the compressed air taken out from the secondary pressure outlet 43 decreases, and accordingly, the pressure in the variable volume pressure chamber 34 decreases, and the vibration isolation table 10 lowers again. When the vibration isolating table 10 is lowered, the measuring capsule 51 moves downward, so that the opening degree of the pilot valve 60 returns to its original state, and the secondary pressure taken out from the secondary pressure outlet 43 also returns to its original state.

As a result of the above operations being repeated, the height position of the vibration isolating table 10 is controlled within a narrow range. As described above, in the present apparatus, the regulator 40 controls the air pressure holding mechanism 3.
A pressure adjusting member (measuring capsule 51, pilot valve 60) for adjusting the pressure of the compressed air supplied to
Since the interlocking is performed so as to move in accordance with the movement of the anti-vibration table 10, the position of the anti-vibration table 10 can be stabilized without requiring a complicated sensor or feedback system.

Further, in the present apparatus, the slide shaft 52 for connecting the measuring capsule 51 and the pilot valve 60 to the vibration isolating table 10 is inserted with a gap between the guide hole 45a on the housing 41 side and is compressed. When the air source 90 is operated, the slide shaft 52 and the housing 41 are configured not to come into contact with each other due to the pressure of the air discharged from the gap to the outside. Since the slide shaft 52 is in a state of being guided through an air bearing, the pilot valve 60 is opened via the slide shaft 52 with respect to the vertical movement of the vibration isolation table 10 with respect to the fixed base 20. The degree can be changed sensitively. On the other hand, the vibration generated in the direction different from the moving direction of the anti-vibration table 10, which is generated on the side of the fixed base 20 to which the housing 41 of the regulator 40 is fixed, is not transmitted to the anti-vibration table 10 via the slide shaft 52. Therefore, the position control accuracy of the vibration isolation table 10 can be increased.

Each of the slide shafts 52 is in contact with the regulator contact surface 10a of the vibration isolating table 10 by a contact projection 53 on a spherical outer surface. While following movement sensitively,
In a plane direction orthogonal to the vertical direction, a force is not easily transmitted from the contact protrusion 53 to the vibration isolating table 10.
For this reason, the vibration of the fixed base 20 side to the vibration isolating table 10 is more difficult to be transmitted to the vibration isolating table 10 in combination with the support of the slide shaft 52 via the air bearing.

[0032]

As described above, according to the present invention, the height position of the vibration isolation table can be precisely controlled by a simple mechanism.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a vibration-isolation table positioning apparatus according to the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is an enlarged sectional view of a regulator part of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Vibration-proof table 10a Regulator contact surface 20 Fixed base 21 Holding frame 22 Opening 30 Air pressure holding mechanism 34 Variable volume pressure chamber 40 Regulator 41 (41a to 41d) Housing 42 Primary pressure inlet 43 Secondary pressure outlet 44 Secondary Pressure chamber 45 Shaft 45a Guide hole 46 49 66 Communication passage 47 Main valve 48 Compression spring 50 Control chamber 51 Measuring capsule (pressure regulating member) 52 Slide shaft 53 Contact protrusion 60 Pilot valve (pressure regulating member) 61 Floating piston 65 Pilot pressure chamber 68 Leaf spring 70 Bleed hole 75 Exhaust hole 76 Radial passage 77 Relief chamber 78 Relief hole 79 Relief valve 80 Compression spring 90 Compressed air source

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F16K 17/02 F16K 17/04 H 17/04 17/06 B 17/06 17/164 17/164 17 / 34 F 17/34 F16M 5/00 D F16M 5/00 7/00 B 7/00 J F15B 11/06 H F term (reference) 3H059 AA06 AA07 AA17 BB05 BB06 CA13 CA15 CB12 CB14 CC02 CD05 CD13 DD06 DD07 DD14 FF04 3H060 AA02 BB01 BB04 BB10 CC07 DB12 DC05 DD02 DD04 DD05 DD12 DD17 EE04 FF03 FF06 HH06 3H089 AA58 CC01 DA02 DB03 GG03 HH05 JJ20 3J048 AA02 AD02 BE02 CB09 DA01 EA13

Claims (5)

[Claims] A fixed base; an anti-vibration table supported in a fixed direction with respect to the fixed base; formed between the fixed base and the anti-vibration table; A compressed air source for supplying compressed air to the air pressure holding mechanism; a compressed air source provided between the air pressure holding mechanism and the compressed air source to supply compressed air to the air pressure holding mechanism. A regulator capable of adjusting the pressure;
A pressure adjusting member that changes the compressed air pressure supplied from the regulator to the air pressure holding mechanism by the movement; and a pressure adjusting member that is provided between the pressure adjusting member and the vibration isolation table, and moves the vibration isolation table in a predetermined direction with respect to the fixed base. A positioning device for an anti-vibration table, comprising: a pressure adjusting member moving mechanism that moves the pressure adjusting member. 2. The vibration isolating table positioning device according to claim 1, wherein the pressure adjusting member moving mechanism does not transmit the vibration of the regulator in a direction other than the moving direction of the vibration isolating table to the vibration isolating table. Positioning device. 3. The positioning device for a vibration isolating table according to claim 2, wherein the pressure adjusting member is movable along a moving direction of the vibration isolating table with respect to the fixed base. A slide shaft extending parallel to the movement direction of the vibration isolating table, one end of which is connected to the pressure regulating member and the other end of which is in contact with the vibration isolating table; A guide hole having a diameter larger than that of the slide shaft, which is inserted so as to be movable in the axial direction; and when the compressed air source supplies compressed air to the regulator, a gap between the slide shaft and the guide hole. Air is discharged from the regulator to the outside of the regulator, and the air keeps the slide shaft and the guide hole out of contact with each other. 4. The positioning device for a vibration isolation table according to claim 3, wherein the vibration isolation table has a contact surface with a slide shaft orthogonal to a moving direction of the table. An apparatus for positioning a vibration isolating table having a spherical contact portion abutting against a contact surface of a shaking table. 5. The positioning device for a vibration isolator according to claim 1, wherein the regulator comprises: a primary pressure inlet connected to the compressed air source so as to allow air to flow therethrough; and the air pressure holding mechanism. A main pressure valve that opens and closes between the primary pressure inlet and the secondary pressure chamber; and a bleed hole through which compressed air in the secondary pressure chamber can flow and communicates with the outside. A pilot chamber having: a main valve that is moved according to a pressure difference between the secondary pressure chamber and the pilot pressure chamber, opens the main valve while moving to the secondary pressure chamber side, and moves to the pilot pressure chamber side. A floating piston for closing the main valve when the main valve is closed; and an exhaust mechanism for discharging the air from the secondary pressure chamber to the outside when the floating piston moves to the pilot pressure chamber and the main valve is closed. Having the pressure regulating member, A pilot valve for controlling the introduction of air from the secondary pressure chamber to the pilot pressure chamber; and a pilot valve interposed between the pilot valve and the slide shaft, which expands and contracts in accordance with the pressure of the secondary pressure chamber. And a measuring capsule to be opened and closed.