JPH0776576B2 - Position control valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is a novel non-linear operation in which a return operation is performed rapidly when the reference position is largely deviated, and the return operation is gentle when the reference position is approached. The present invention relates to a mold position control method and a position control valve utilizing the method.

(Prior art and its problems) Generally, the vibration isolation device is in a stable state at the reference position, but becomes unstable or chattering occurs when the supply / exhaust amount of the vibration isolation device rapidly increases at the reference position. It will be easier. Therefore, in order to stabilize the servo mechanism that controls the position of the vibration isolation device, it is common to adjust the state parameter to a stable region by using an orifice or the like. However, this method has a problem in that the anti-vibration device is regulated by the orifice and the rise of the anti-vibration device is delayed, or the operation time is delayed.

(Object of the Invention) The present invention has been made in view of the drawbacks of the conventional example,
When the target position is largely deviated from the reference position, the inflow / outflow amount of air in the position control actuator such as the cylinder or air spring is increased to perform a rapid return operation, and the position is close to the reference position. It is another object of the present invention to provide a non-linear type position control valve in which the amount of inflow and outflow of air in the actuator is narrowed so that the return operation is slowed to prevent an early return to the reference position and chattering.

(Means for Solving Problems) The present invention is directed to solving the problems according to the first item; (a) A cylinder for supporting a vibration isolation table main body or a position control actuator such as an air spring is connected. A valve body having an I / O port, an exhaust for releasing the atmosphere, and an import connected to a compressed air source, and (b) moving in the valve body in conjunction with the movement of the vibration isolation table body. When the plunger closes the import and the plunger is in contact with the valve, the I / O port is exhausted. And the import is not connected either, the reference position of the vibration isolation table main body is set by this, the vibration isolation table main body moves out of the reference position due to the load reduction, and the I / O port and the exhaust for atmosphere release are connected. ,position Is returned to the anti-vibration table body reference position pressure is reduced in the control actuator, conversely, the import and I / O port from the anti-vibration table body reference position when the load is increased out on the opposite side is connected,
It is configured such that the compressed air source supplies air to the position control actuator to return the vibration isolation table body to the reference position.
Consists of a directional valve, and I / O when there is a large deviation from the reference position of the vibration isolation table body
If the supply / exhaust volume of the port is large and the deviation from the reference position is small, the supply / exhaust volume of the I / O port is changed according to the size of the positional deviation so that the supply / exhaust volume of the I / O port becomes small. A flow channel structure is provided.

In the second item, the I / O chamber (3) communicating with the position control actuator (2) such as a cylinder or an air spring supporting the vibration isolation table body (1) is adopted in the second section. An import chamber (5) communicating with the compressed air source (4) and an exhaust chamber (6) for releasing the air in the position control actuator (2) to the atmosphere are provided in the valve body (7), and the import chamber (5) The air supply opening (8) of the I / O chamber (3) that can be opened to the side is pressed and urged toward the I / O chamber (3) side, and becomes tapered toward the I / O chamber (3). Open / close valve (9
a) is arranged so that it can be opened and closed, and the slide cylinder part (9a) protruding toward the small diameter side of the tapered on-off valve (9a) is moved from the I / O chamber (3) to the exhaust chamber (6).
Insert it so that the outer peripheral surface becomes airtight, and insert the exhaust chamber and I / O chamber (6) into the slide cylinder (9a).
A plunger that has a communication hole (14) for connecting to and slides along with the movement of the vibration isolation table body (1), and its insertion end is constantly urged in a direction away from the slide cylinder part (9a). (10) Exhaust chamber (6)
The cone-shaped valve (10
(a) is openably and closably arranged in the exhaust chamber side opening (14a) of the communication hole (14).

In the third section; the I / O chamber (3) communicating with the position control actuator (2) such as a cylinder or an air spring supporting the vibration isolation table body (1); The import chamber (5) communicating with the compressed air source (4) and the exhaust chamber (6) for releasing the air in the air spring (2) to the atmosphere are provided in the valve body (7) and opened in the import chamber (5). The air supply opening (8) of the I / O chamber (3) is provided with a flat plate-shaped on-off valve (9b) that is biased toward the I / O chamber (3) side, and the vibration isolation table body (1) The insertion end of the I / O chamber (3) protrudes and sinks into the import chamber (5) side according to the movement of the
The plunger (10) that pushes the flat-shaped on-off valve (9b) into the import chamber (5) at the insertion end surface at the time of protrusion is slidably inserted into the valve body (7), and the insertion end of the plunger (10) is The tip part is the I / O room (3)
As the large diameter part (12) with a diameter slightly smaller than the inner diameter of
A small gap is formed between 2) and the I / O chamber (3), and the part adjacent to the large diameter part (12) of the plunger (10) is smaller in diameter than the large diameter part (12). 13), a communication hole (14) communicating with the exhaust chamber (6) from the insertion end surface of the plunger (10) that abuts the flat valve (9b) is bored in the plunger (10).

In the fourth item, there is an I / O chamber (3) communicating with a position control actuator (2) such as a cylinder or an air spring that supports the vibration isolation table body (1). The import chamber (5) communicating with the compressed air source (4) and the exhaust chamber (6) for releasing the air in the air spring (2) to the atmosphere are provided in the valve body (7) and opened in the import chamber (5). In the air supply opening (8) of the I / O chamber (3), a spherical opening / closing valve (9c) that is biased toward the I / O chamber (3) side is provided, and the vibration isolation table main body (1) In accordance with the movement, the insertion end of the I / O chamber (3) protrudes and sinks into the import chamber (5) side,
When projecting, the plunger (10) that pushes the spherical on-off valve (9c) into the import chamber (5) at its insertion end surface is slidably inserted into the valve body (7), and the tip of the insertion end of the plunger (10) is inserted. I / O room (3)
As the large diameter part (12) with a diameter slightly smaller than the inner diameter of
A small gap is formed between 2) and the I / O chamber (3), and the part adjacent to the large diameter part (12) of the plunger (10) is smaller in diameter than the large diameter part (12). 13) and a communication hole (1) that communicates with the exhaust chamber (6) from the insertion end face of the plunger (10) that abuts the spherical on-off valve (9c).
Drill 4) into the plunger (10).

In the fifth item; in the second to fourth items, one end of the operating arm (28) for operating the plunger (10) is swingably supported by the valve body (A). The technical means of installing the actuating part (29) abutting on the vibration isolation table main body (1) on the actuating arm (28) so that the mounting position can be changed on the free end side is adopted.

(Operation) When a load such as a device is placed on the vibration isolation table body (1), the vibration isolation table body (1) sinks according to the load.

Then, the plunger (10) of the valve (A) for the vibration isolation device is pushed down together with the vibration isolation table body (1), and the plunger (1)
The insertion end of (0) pushes down the on-off valve (9) to connect the import chamber (5) and the I / O chamber (3).

Then, compressed air is supplied from the import chamber (5) through the I / O chamber (3) to the actuator (2), and the vibration isolation table body (1) is pushed up.

Here, when the amount of pushing down the vibration isolation table main body (1) is large, a large amount of compressed air suddenly flows into the actuator (2) to rapidly push up the vibration isolation table main body (1).

When the anti-vibration table body (1) is pushed up to near the reference position (O), the plunger (10) also rises accordingly and the opening / closing valve (9) opens the I / O chamber (3) and the import chamber (5). Is gradually closed to suppress the inflow of compressed air from the import chamber (5) to the I / O chamber (3). As a result, the vibration isolation table main body (1) is gradually pushed up toward the reference position (O), and the soft landing is performed at the reference position (O).

Conversely, if the load is removed, the vibration isolation table body (1) rises, but if the amount of rise is large, the plunger (10)
Rises, the exhaust chamber (6) of the I / O chamber (3) communicates, air in the actuator (2) suddenly escapes, and the vibration isolation table body (1) rapidly descends.

When the plunger (10) is lowered near the reference position (O), the communication state between the I / O chamber (3) and the exhaust chamber (6) is gradually closed to restrict the escape of air. Soft land on (O).

(Examples) The present invention will be described below with reference to illustrated examples. The vibration isolation table main body (1) is supported by a position control actuator (2) such as a cylinder or an air spring. When the actuator (2) is, for example, an air spring, a rubber spring portion (15) is provided. It is composed of a pressure vessel (17). Hereinafter, the air spring will be described as the actuator (2), but the actuator is not limited to this. In the valve body (7) of the position control valve (A) in the first embodiment, an exhaust (18) for releasing the air in the air spring (2) to the atmosphere,
Import (20) to connect with compressed air source (4) and I / O port (1 to connect to pressure vessel (17) of air spring (2)
9) is provided, and further, an exhaust chamber (6) communicating with the exhaust (18) and an I / O in the valve body (7) are provided.
I / O room (3) communicating with O port (19) and import (2
An import chamber (5) communicating with (0) is provided. The air supply opening (8) of the I / O chamber (3) which can be opened to the import chamber (5) is urged by the pressure spring (21) toward the I / O chamber (3) side, and the I / O is urged. A taper-shaped on-off valve (9a) that gradually narrows toward the chamber (3) is provided so as to be openable and closable, and the taper portion is inserted into the air supply opening (8). A slide cylinder (9d) is provided on the small diameter side of the taper on-off valve (9a) so as to project from the slide cylinder (9d).
d) is inserted from the I / O chamber (3) to the exhaust chamber (6) so that the outer peripheral surface is airtight. Exhaust chamber (6) and I / O chamber (3) in slide cylinder (9d)
A communication hole (14) for connecting the I / O chamber (3) and the I / O chamber side opening (3a) opening to the I / O chamber (3) has a small diameter around the I / O port ( 19). On the other hand, the plunger (10) is slid according to the movement of the vibration isolation table main body (1), and the insertion end of the plunger (10) is constantly urged by the compression spring (26) in the direction away from the slide cylinder (9d). One end is arranged in the exhaust chamber (6). At the insertion end of this plunger (10), a conical valve (10
a) is provided so as to project and is arranged so as to open and close the exhaust chamber side opening (14a) of the communication hole (14). An abutment rod (25) is screwed to the projecting end of the plunger (10) and is in constant contact with the vibration isolation table body (1).

Then, when the load on the vibration isolation table main body (1) is removed, the vibration isolation table main body (1) moves upward as shown in FIG. 2, but following this, the compression spring (26) The action moves the plunger (10) in the direction to pull it out, and the plunger (10)
Of the conical valve (10a) is released from the exhaust side opening (14a) formed in the slide cylinder (9d), the I / O chamber (3) and the exhaust chamber (6) communicate with each other, and the air spring ( Air in the pressure vessel (17) of 2) passes from the I / O chamber (3) to the exhaust chamber (6) through the communication hole (14), is released to the atmosphere, and the pressure in the air spring (2) decreases. To do. At this time, when the amount of rise of the vibration isolation table main body (1) is large, the exhaust side opening (14a) is completely opened, and as a result, the pressure drop in the air spring (2) suddenly occurs, and the vibration isolation table main body ( The descent in 1) will be performed rapidly. This is indicated by the solid line in Figure 12 (b).
Indicate. When the vibration isolation table main body (1) reaches near the reference position (O), the conical valve (10a) gradually closes the exhaust side opening (14a) and suppresses the outflow of air. As a result, the anti-vibration table main body (1) gradually descends toward the reference position (O), and finally soft-landes to the reference position (O). This state is shown in Fig. 3, and the I / O port (1
The state of air supply in 9) is shown in the region (b) of Fig. 12 (the portion where the inclination angle is gentle).

On the contrary, as shown in FIG. 4, when the vibration isolation table main body (1) is pushed down by a load, the plunger (10) is also pushed down accordingly, and the tapered open / close valve is resisted against the pressing spring (21). (9a) is also pushed down. Then, the import room (5) and the I / O room (3) communicate with each other, and the import room (5)
The compressed air from the compressed air source (4) is supplied to the pressure vessel (17) of the air spring (2) through the I / O chamber (3), and the vibration isolation table body (1) is pushed up. Act on. Here, when the amount of pushing down the main body of the vibration isolation table (1) is large, the taper-shaped on-off valve (9a) is largely protruded into the import chamber (5), and the air supply opening (8) is greatly opened, resulting in a sudden opening. Compressed air flows into the I / O chamber (3) and the main body of the vibration isolation table (1)
Push up sharply. The state of exhaust of the I / O port (19) at this time is shown in Fig. 12 (c). When the anti-vibration table body (1) is pushed up to near the reference position (O), the plunger (10) and the taper on-off valve (9a) are also raised by the action of the compression spring (26) and the pressing spring (21). However, as it approaches the reference position (O), the air supply opening (8) is gradually closed by the tapered on-off valve (9a), and the compression from the import chamber (5) to the I / O chamber (3) is performed. The inflow of air is suppressed, and the vibration isolation table main body (1) is gradually pushed up toward the reference position (O) to soft-land to the reference position (O). The exhaust state of the I / O port (19) at this time is the area (d) in FIG. (Note that the above-mentioned area (b) and area (d) are shown only by solid lines, but the other two areas are also the same.) Next, a second embodiment of the present invention will be described. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In this case, instead of the tapered on-off valve (9a), the air supply opening (8) of the I / O chamber (3) that can be opened to the import chamber (5)
Further, a plate-like on-off valve (9b) is provided, which is biased by the pressure spring (21) toward the I / O chamber (3). In addition, the insertion end of the vibration isolation table body (1) protrudes and retracts from the I / O chamber (3) to the import chamber (5) side when the vibration isolation table body (1) moves. The plunger (10) is slidably inserted into the valve body (7) so that the plunger (10) is pushed into the import chamber (5) at its insertion end face. The tip of the insertion end of the plunger (10) is a large diameter part (12) having a diameter slightly smaller than the inner diameter of the I / O chamber (3).
A small gap is formed with the O chamber (3). Further, a portion adjacent to the large diameter portion (12) of the plunger (10) is a small diameter portion (13) having a diameter smaller than that of the large diameter portion (12), and the plunger (10) that abuts the flat on-off valve (9b). A communicating hole (14) communicating with the exhaust chamber (6) from the insertion end surface of (1) is formed in the plunger (10). The plunger (10) is inserted into the valve body (7) so as to pass through the exhaust chamber (6) and the I / O chamber (3), but the exhaust chamber (6) and the I / O chamber (3) And are separated by a partition. On the other hand, the import chamber (5) and the I / O chamber (3) are separated by a flat open / close valve (9b), and the open / close valve (9b) is separated by the pressing spring (21) from the I / O chamber ( It is always pressed and urged toward the 3) side. The outer peripheral surface of the portion of the plunger (10) located in the I / O chamber (3) is formed in a stepped shape, and this portion is the large diameter portion (12) and the small diameter portion (13) as described above. . The large diameter portion (12) and the small diameter portion (13) move in front of the I / O opening (22) of the I / O chamber (3) communicating with the I / O port (19). Also, the corner of the bottom of the large diameter part (12) is tapered (23)
Is provided. A communication hole (14) opening from the I / O chamber (3) to the exhaust chamber (6) is bored from the insertion end face which is the bottom face of the plunger (10) to the central side face of the plunger (10). A washer nut (24) is screwed to the projecting end of the plunger (10), and an abutment rod (25) is screwed to the washer nut (24) to abut the vibration isolation table body (1). ing. The plunger (10) is urged in the pull-out direction by the compression spring (26) that is in contact with the seat nut (24), and the contact rod (25) always contacts the vibration isolation table body (1). It is like this.

Then, when the load on the vibration isolation table main body (1) is reduced or removed, the vibration isolation table main body (1) moves upward as shown in FIG. The plunger (10) moves in the direction of being pulled out by the action of the compression spring (26), the bottom surface of the plunger (10) is separated from the opening valve (9), and the bottom opening portion (27) of the plunger (10) is released. . At the same time, the large-diameter portion (12) is released upward from the I / O opening (22) to release the I / O opening (22). Then, the air in the pressure vessel (17) of the air spring (2) escapes from the I / O chamber (3) to the exhaust chamber (6) through the communication hole (14),
The pressure in the air spring (2) is reduced by releasing the atmosphere. At this time, when the amount of rise of the vibration isolation table main body (1) is large, the large diameter part (12) is completely disengaged from the I / O opening part (22) and the opening degree becomes large, resulting in the air spring (2). The pressure inside the machine suddenly drops, and the vibration isolation table main body (1) drops rapidly. When the main body (1) of the vibration isolation table reaches near the reference position (O), the large diameter part (12) is positioned (O) in front of the I / O opening (22) and the I / O opening (22). The opening degree of is reduced to suppress the outflow of air from the I / O opening (22). As a result, the vibration isolation table body (1) gradually descends toward the reference position (O),
Finally, soft landing is performed at the reference position (O). On the contrary, when a load is applied to the vibration isolation table main body (1) to push it down, the plunger (10) is also pushed down as shown in FIG. 6, and the on-off valve (21) is pushed against the pressing spring (21). 9) Push down. Then, the import chamber (5) and the I / O chamber (3) communicate with each other, and the compressed air from the compressed air source (4) from the import chamber (5) passes through the I / O chamber (3) to the air spring (2). ) Is supplied to the pressure vessel (17) and acts in the direction of pushing up the vibration isolation table body (1). Here, when the amount of pushing down the main body of the vibration isolation table (1) is large, the import chamber (5) up to the small diameter part (13) at the insertion end of the plunger (10)
Small diameter part (1
Compressed air suddenly flows into the I / O chamber (3) between the outer diameter of 3) and the inner diameter of the I / O chamber (3), and the vibration isolation table body (1) is suddenly pushed up. Vibration isolation table body (1) up to near the reference position (O)
When is pushed up, the plunger (10) also rises due to the action of the compression spring (26), but as shown in FIG. 7, the large diameter part (12) is the import of the I / O chamber (3) at this position. Almost closes the air supply opening (8) with the chamber (5) and suppresses the inflow of compressed air from the import chamber (5) into the I / O chamber (3). As a result, the vibration isolation table main body (1) is gradually pushed up toward the reference position (O), and the soft landing is performed at the reference position (O).

The third embodiment of the present invention is almost the same as the second embodiment,
The third embodiment uses a spherical on-off valve (9c) in contrast to the flat-shaped on-off valve (9b) of the second embodiment, and bamboo shoots at the taper-shaped air supply opening (8a). They are different in that they are pressed and urged toward the I / O chamber (3) side by a ring-shaped pressure spring (21a). In this case, the large diameter portion (12) and the small diameter portion (1
Due to the presence of 3), the change of the air supply amount at the time of closing by the spherical opening / closing valve (9c) of the air supply opening (8) becomes smoother toward the reference position (O), and as a result, the flat opening / closing valve. (9b)
It will be a smoother soft landing.

It should be noted that the change in the clearance immediately before the spherical opening / closing valve (9c) comes into contact with or separates from the tapered air supply opening (8a) becomes slower than that of the flat opening / closing valve (9b). As shown in FIG. 11, the distance between the soft landing areas (b) and (d) having a small angle before and after the reference position (O) becomes longer, which enables more stable soft landing. In the figure, the solid line is the spherical open / close valve (9c), and the broken line is the flat open / close valve (9b).
Is.

In FIGS. 10 and 11, the vertical axis represents the supply / exhaust flow rate at the I / O port (19), the horizontal axis represents the stroke, and (O) is the reference position.

Thus, the valves (A) of the first to third embodiments of the present invention are
When a certain amount of deviation from the reference position (O) occurs, a rapid return operation is performed, and when it approaches the reference position (O), an extremely slow return operation is performed. It is possible to realize an early return to the reference position (O) without chattering in 1).

The description has been centered on the case where the position control valve (A) is used for level return of the vibration isolation table main body (1), but of course the present invention is not limited to this, and for return to the reference position (O) in the horizontal position. It can also be used.

Further, as shown in FIG. 12, one end of the actuating arm (28) for actuating the plunger (10) in the valve (A) of the first to third embodiments is swingably supported by the valve body (A) for vibration isolation. The actuating part (29) that abuts the base body (1) may be installed on the actuating arm (28) so that the mounting position can be changed on the free end side. In this case, the actuating part (29) to the fulcrum (30) can be installed. The characteristics of the soft landing can be adjusted by the ratio of the distance and the distance from the plunger (10) to the fulcrum (30). That is, the longer the distance to the operating point (29), the longer the convergence time is 2 as shown by the one-dot chain line or two-dot chain line in FIG.
It is possible to give the optimum soft landing state to the applicable equipment by appropriately selecting the length up to the operating point (29), which varies from double to triple.

(Effect) Since the present invention adopts the above control method and the structure that can realize this control method, when the vibration isolation table body deviates from the reference position due to the load reduction, the I / O port and the atmosphere are released. When the exhaust is connected, the air pressure inside the actuator for position control decreases and the vibration isolation table body returns to the reference position.
On the contrary, when the vibration isolation table main body comes off from the reference position on the opposite side when the load increases, the I / O port and the import are connected and the position control actuator is supplied with air from the compressed air source and the vibration isolation table main body moves to the reference position. However, if the air supply / exhaust volume of the I / O port fluctuates greatly from the reference position in response to the amount of displacement, the air supply / exhaust volume will increase and the air will rapidly return to the reference position. As the amount of exhaust air supply is throttled when approaching the reference position, the return operation to the reference position becomes gradual, and finally the soft landing is performed to the reference position, and quick return to the reference position and prevention of chattering can be realized. It is a thing.

[Brief description of drawings]

FIG. 1 ... Front view for explaining the usage state of the present invention FIG. 2-4 ... Cross-sectional view showing the operating state of the valve of the first embodiment of the present invention FIG. 5-7 ... Second embodiment of the present invention Sectional view showing the operating state of the valve FIG. 8 ... Sectional view showing the operating state of the valve of the third embodiment of the present invention FIG. 9 ... Convergence state of soft landing during control when the operating point of the present invention is changed 10 is a graph showing the relationship between the supply / exhaust flow rate and the stroke in FIG. 11. FIG. 11 is a graph comparing the control states due to the difference in the on-off valve of the present invention. FIG. 12 is the valve of the present invention. Front view when arm is installed on (A) …… Position control valve, (O) …… Reference position (1) …… Vibration isolation table body, (2) …… Air spring (3) …… I / O chamber, (4) …… Compressed air source (5) …… Import chamber, (6) …… Exhaust chamber (7) …… Bar Main body, (8) …… Air supply opening (8a) …… Tapered air supply opening (9) …… Open / close valve, (9a) …… Tapered open / close valve (9b) …… Plate shape On-off valve, (9c) …… Spherical on-off valve (9d) …… Slide tube part, (10) …… Plunger (10a) …… Conical valve (12) …… Large diameter part, (13)… … Small diameter part (14) …… Communication hole, (14a) …… Exhaust side opening (15) …… Spring part, (17) …… Pressure vessel (18) …… Exhaust, (19) …… I / O port (20) …… Import, (21) …… Pressing spring (22) …… I / O opening, (23) …… Taper (24) …… Seat nut, (25) …… Abutment rod (26) ...... Compression spring, (27) …… Bottom opening (28) …… Working arm, (29) …… Working part (30) …… fulcrum

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-10133 (JP, A) Actually open 63-86401 (JP, U) Actually open 62-170802 (JP, U) Actually open 58- 49002 (JP, U)

Claims (5)

[Claims] 1. (a) Connected to a position control actuator such as a cylinder or an air spring that supports a vibration isolation table body.
A valve body having an I / O port, an exhaust for atmosphere release, and an import connected to a compressed air source, (b) moving in the valve body in conjunction with the movement of the vibration isolation table body A plunger portion, and (c) a valve body that opens and closes the import, and when the valve body closes the import and the plunger portion is in contact with the valve body, the I / O port is an exhaust and It is not connected to any of the imports, this sets the reference position of the vibration isolation table main body, the vibration isolation table main body deviates from the reference position due to load reduction, and the I / O port and the exhaust for atmospheric release are connected, The air pressure inside the actuator for position control drops and the vibration isolation table body returns to the reference position. Conversely, when the load increases, the vibration isolation table body moves away from the reference position on the opposite side, and the I / O port and import are connected. Done It consists of a three-way valve configured so that the position control actuator is supplied with air from the compressed air source to return the vibration isolation table body to the reference position. If there is a large deviation from the reference position of the vibration isolation table body, I If the supply / exhaust volume of the I / O port is large and the deviation from the reference position is small, the supply / exhaust volume of the I / O port should be adjusted so that the supply / exhaust volume of the I / O port becomes small. A position control valve having a variable flow path structure. 2. An I / O chamber communicating with a position control actuator such as a cylinder or an air spring that supports the vibration isolation table body,
The valve body is equipped with an import chamber that communicates with the compressed air source and an exhaust chamber that releases the air in the position control actuator to the atmosphere, and the I / O chamber side is located at the air supply opening of the I / O chamber that opens to the import chamber. A tapered open / close valve that is gradually biased toward the I / O chamber by being pressed by the open / close valve is arranged to be openable / closable, and the slide cylinder that protrudes to the small diameter side of the tapered open / close valve is removed from the I / O chamber. It is inserted through the exhaust chamber so that its outer peripheral surface becomes airtight, a communication hole connecting the exhaust chamber and the I / O chamber is drilled in the slide cylinder part, and it slides according to the movement of the vibration isolation table main body, and A plunger, whose insertion end is constantly biased in a direction away from the slide cylinder, is installed in the exhaust chamber, and a conical valve that projects from the insertion end of the plunger is openably and closably attached to the opening on the exhaust chamber side of the communication hole. Characterized by being installed Position control valve that. 3. An I / O chamber communicating with a position control actuator such as a cylinder or an air spring that supports the main body of the vibration isolation table,
The valve body is equipped with an import chamber that communicates with the compressed air source and an exhaust chamber that releases the air in the air spring to the atmosphere, and an I / O is provided at the air supply opening of the I / O chamber that opens to the import chamber.
A flat valve that is pressed and urged to the chamber side is provided, and the insertion end of the I / O chamber protrudes from the I / O chamber to the import chamber side according to the movement of the vibration isolation table body. Insert the plunger that pushes into the import chamber with its insertion end face slidably into the valve body, and make the tip of the insertion end of the plunger a large diameter part slightly smaller than the inner diameter of the I / O chamber.
A small gap is formed between the large diameter part and the I / O chamber, and the part adjacent to the large diameter part of the plunger is made a smaller diameter part smaller than the large diameter part. A position control valve characterized in that a communication hole that communicates from the insertion end face to the exhaust chamber is formed in the plunger. 4. An I / O chamber that communicates with a position control actuator such as a cylinder or an air spring that supports the main body of the vibration isolation table,
The valve body is equipped with an import chamber that communicates with the compressed air source and an exhaust chamber that releases the air in the air spring to the atmosphere, and an I / O is provided at the air supply opening of the I / O chamber that opens to the import chamber.
A spherical on-off valve that is pressed and urged to the chamber side is provided, and its insertion end protrudes and retracts from the I / O chamber to the import chamber side according to the movement of the anti-vibration table main body. Insert the plunger that pushes into the import chamber at the insertion end face into the valve body slidably, and make the tip end of the insertion end of the plunger a large diameter part slightly smaller than the inside diameter of the I / O chamber. A small gap is formed between the plunger and the large diameter part, and the part adjacent to the large diameter part is made a smaller diameter part smaller than the large diameter part.Communication that communicates with the exhaust chamber from the insertion end face of the plunger that contacts the spherical opening / closing valve. Position control valve characterized by being formed with a hole in the plunger. 5. An actuating arm for operating a plunger is slidably supported on a valve body, and an actuating portion abutting against a vibration isolation table main body is installed on a free end side of the actuating arm so as to be capable of changing an ordering position. The position control valve according to any one of claims 2 to 4, characterized in that: