JPH09303577A - Gate valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the occurrence of particles causing pollution in the gate valve. SOLUTION: The gate valve is so designed that a first opening 14 and a second opening 15 are formed in the front surface wall 22 of a valve main body 11 having a valve chamber 16 inside, and in a rear surface wall 23 respectively, a valve seat 24 is formed in the inside of the first opening 14 or the second opening 15, a gate 18 is connected with the base end of a valve shaft 19 performing a straight ahead movement, and the gate 18 is pressed to the valve seat 24 so as to allow the valve to be closed. The valve shaft 19 is inserted into the center hole of the support wall 26 of the valve main body in a non-contact condition, the side surface of the valve shaft 19 out of the valve chamber 16, is covered with bellows 37 in a non-contact condition, a space between the tip end of the bellows 37 and the tip end part of the valve shaft 19 is kept in airtightness, and a space between the base end of the bellows 37 and the circumference of the center hole of the support wall 26 is also kept in airtightness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gate valve that opens and closes a vacuum transfer passage and a vacuum chamber. This gate valve is applied to a transfer passage having a rectangular section when transferring a work such as an integrated circuit (IC) or its components from the vacuum processing chamber to the vacuum processing chamber.

[0002]

BACKGROUND OF THE INVENTION When inserting a gate assembly between an inlet opening and an outlet opening of a valve body, the force of the insertion is used to seal the plate of the gate assembly to the valve seat of the inlet opening or the outlet opening. A gate valve (see, for example, Japanese Patent Publication No. 2-8185) is considered. In the gate assembly of this gate valve, plates are arranged on both sides of the actuator plate, and four plates are provided on each of the facing surfaces of the two plates and the actuator plate.
Individual storage grooves are formed, and rollers having a rectangular cross section are arranged in the storage grooves. When the gate assembly is inserted into the valve body by the driving member, the rollers having a square cross section are tilted to spread the two plates of the gate assembly, and the plates are pressed against the inlet opening or the outlet opening to seal.

In the conventional gate valve, the structure of the gate assembly is considerably complicated, and there is no barrier between the gate assembly and the vacuum transfer passage. Therefore, particles (fine particles) generated by the operation of the plate of the gate assembly enter the transfer passage and the vacuum chamber, and contaminate those spaces. Such contamination causes deterioration of the quality of the integrated circuit or the like and must be avoided.

[0004]

SUMMARY OF THE INVENTION The first object of the present invention is to reduce the generation of particles that cause contamination in a gate valve, and convert the linear motion of the drive member into the swing motion of the gate. Second to close the passage by
And the subject.

[0005]

According to the present invention, in order to achieve the above object, a first opening and a second opening are formed in a front wall and a rear wall of a valve body having a valve chamber therein, respectively. A gate valve, wherein a valve seat is formed inside the opening or the second opening, a gate is connected to a base end of a valve shaft performing a rectilinear motion, and the gate is pressed against the valve seat to close the valve. The shaft is inserted into the center hole of the support wall of the valve body in a non-contact state, the side surface of the valve shaft outside the valve chamber is covered in a non-contact state by the bellows, and the space between the tip of the bellows and the tip of the valve shaft is airtight. According to the present invention, the space between the base end of the bellows and the periphery of the central hole of the support wall is made airtight. According to a first aspect of the present invention, a guide ring is fitted into a central hole of a support wall, the valve shaft is inserted into the guide ring so as to maintain a non-contact state, and a flange is integrally formed at a tip portion of the valve shaft. According to the second aspect of the present invention, the bellows are formed so that the tip end of the bellows is fixed to the back surface of the flange in an airtight state and the base end of the bellows is fixed to the guide ring in an airtight state. The present invention provides the first engagement according to claim 1 or 2, wherein an engaging portion having a front surface and a rear surface is formed integrally with or separately from the valve shaft at a tip of the valve shaft, and is rotatably supported by a roller supporting member. The front surface and the rear surface of the engaging portion are sandwiched by a roller and a second engaging roller, the movable plate is guided so as to perform a rectilinear motion, the roller supporting member is fixed to the movable plate, and the left and right sides of the valve shaft front end surface are fixed. A third aspect of the present invention is that springs are mounted between both ends and the movable plate. According to the present invention, a first opening and a second opening are respectively formed in a front wall and a rear wall of a valve body having a valve chamber inside, and a valve seat is formed inside the first opening or the second opening, so that a linear motion is achieved. In a gate valve in which a gate is connected to the base end of a valve shaft to perform, and the gate is pressed against a valve seat to close the valve, after the gate reaches a position opposite to the valve seat by the linear motion of the valve shaft, The gate is pressed against the valve seat by the swinging motion of the valve shaft. According to the present invention, in any one of claims 1, 2 and 4, an engaging portion having a front surface and a rear surface is formed at the tip of the valve shaft integrally with or separately from the valve shaft, and is rotatably attached to the roller support member. The front surface and the rear surface of the engaging portion are respectively engaged by the supported first engaging roller and second engaging roller, and the fulcrum roller connected to the tip end portion of the valve shaft is supported at the base end of the fulcrum groove. When the roller support member is moved forward, the first engagement roller engages with the inclined surface portion (for example, the inclined portion / lower end side flat surface) of the front surface so that the valve shaft pushes the gate against the valve seat. It is defined as claim 5 that it is configured to swing. According to a fifth aspect of the present invention, when the gate is pressed against the valve seat, the roller support member is retracted so that the second engagement roller engages with the inclined surface portion (for example, the inclined portion / lower end side flat surface) of the rear surface. According to the present invention, the valve shaft is caused to swing in the direction away from the valve seat. Claim 5
The slanted surface portions in 6 and 6 are inclined (parallel to the surface of the engaging portion) of the first engagement roller and the second engagement roller with respect to the forward or backward direction of the roller support member. It means that there is no restriction on the shape of the part. According to the present invention, in claim 5 or 6, the pedestal is fixed to the support wall of the valve body, and a vertically long fulcrum groove into which the fulcrum roller is inserted is formed in the pedestal. The front guide roller and the rear guide roller, which have a receiving surface and are rotatably supported by the roller supporting member, include the first receiving surface and the second receiving surface.
Claims 7 and 8 are respectively adapted to be engaged with the receiving surfaces. According to the present invention, in any one of claims 5 to 7, the movable plate is guided so as to perform a rectilinear motion, the roller support member is fixed to the movable plate, and the roller shaft is fixed between the tip of the valve shaft and the movable plate. Are connected by a guide rod so as not to be separated by more than a set distance, springs are mounted between the left and right ends of the valve shaft front end surface and the movable plate, and the valve shaft of the valve shaft is connected by the first engaging roller and the second engaging roller. Claim 8 claims that the engaging portion is gripped.

[0006]

1 to 7 show an embodiment of a gate valve according to the present invention. First, the overall structure of the gate valve will be described with reference to FIG. 1 showing the gate fully opened and FIG. 2 showing the gate lowered. In the description of the embodiments, the left side will be referred to as the front side and the right side will be referred to as the rear side, and the description will be made according to the direction in the drawings. However, the expressions used in the claims and the like are also shown in parentheses as necessary. The gate valve has a lower valve body 11 and an upper gate drive unit 12. Valve body 11
Is a rectangular parallelepiped, and a front wall 22 (left side wall in FIG. 1 (b)) and a rear wall 23 (right side wall in FIG. 1 (b)) have a first opening 14 and a second opening 15 each having a rectangular opening surface. Has been formed.
A valve chamber 16 is formed in the valve body 11, and a plate-shaped gate (valve body) 18 and a cylindrical valve shaft 19 are inserted into the valve chamber 16 in a linearly movable and swingable state. The gate 18 is fixed to the lower end (proximal end) of the valve shaft 19 with bolts or the like, a groove is formed near the outer periphery of the rectangular front surface of the gate 18, and the seal member 20 is attached to the groove. The periphery of the first opening 14 inside the front wall 22 serves as a valve seat 24, and the sealing member 20 serves as the valve seat 24.
By being pressed against the first opening 14 and the second opening 15
The communication between the first opening 14 and the second opening 15 is communicated with each other by disconnecting the communication with the seal member 20 and separating from the valve seat 24.

The gate drive unit 12 is connected to a support wall (upper wall in FIG. 1) 26 of the valve body 11. The lower ends (base ends) of the guide shafts 27A and 27B are located on the left end side (one end side) of the support wall 26.
Are connected to the drive device 28 on the right end side (the other end side) of the support wall 26.
The lower end (base end) of the guide shaft is connected, and guide shafts 27A and 27B
The upper end (tip) of the drive device 28 and the upper end (tip) of the drive device 28 are connected by a connecting member 29. Guide shaft 27A ・ 27
Plate-like covers 30A and 30B connecting the support wall 26 and the connecting member 29 are provided on the left end side of B and the right end side of the drive unit 28, respectively. The output member 31 of the drive device 28 performs only a linear movement, and for example, a rodless air cylinder is used. The guide cylinder 33 is slidably fitted to the guide shafts 27A and 27B, and the left end of the movable plate 32 in which the insertion holes 34A and 34B are inserted into the guide shafts 27A and 27B is located at the upper end (tip) of the guide cylinder 33. It is connected. Movable plate
The right end of 32 is connected to the output member 31, and the drive plate 28 causes the movable plate 32 to move linearly.

Main parts of the gate drive section 12 will be described with reference to FIGS. A stepped central hole is formed in the center of the support wall 26, and a flanged guide ring 35 is fitted into the stepped central hole from above. The flanged guide ring 35 is supported by a bolt on the support wall 26.
It is fixed to. The inner peripheral surface of the stepped central hole is covered with a flanged guide ring 35, and the valve shaft 19 is inserted into the flanged guide ring 35 so as to maintain a non-contact state. A flange 36 is integrally formed on the upper end (tip) of the valve shaft 19, and two counterbored holes 38A and 38B for spring reception are formed on the upper surface (front surface) of the flange 36 (FIG. 6 (a)). )). The tip of a metal bellows 37 is welded to an annular portion on the lower surface (back surface) of the flange 36 by welding, and the lower end (base end) of the bellows 37 is a guide ring 35.
Welded tightly to the surface of the valve shaft 19
Is inserted inside the bellows 37 so as to maintain a non-contact state. The bellows 37 seals the space between the upper end of the valve shaft 19 and the guide ring 35, and the space between the inside of the bellows 37 and the outside of the valve shaft 19 communicates with the valve chamber 16. There is no communication with the atmosphere through the gap between 19 and the guide ring 35. And the valve chamber 16 is
Portions other than the first opening 14 and the second opening 15 are hermetically sealed and communicated with the outside through only the first opening 14 and the second opening 15. The bellows 19 may be made of synthetic resin and may be adhered to the annular portion of the lower surface of the flange 36 and the surface of the guide ring 35 with an adhesive. The upper end of the bellows 37 is fixed to the outer surface of the upper end of the valve shaft 19 in an airtight manner, and the lower end of the bellows 37 is fixed to the guide ring 35.
It may be fixed in an airtight state to the support wall 26 around the.

At the upper end of the valve shaft 19, as shown in FIGS. 6 (a), (c),
The cap body 41 shown in (d) is fixed. As shown in the figure, the cap body 41 has an engaging portion 42 protruding upward,
There is an intermediate portion 43 in the shape of two straight lines and two arcs parallel to each other in a top view, and two vertically long support members 44A and 44B having a substantially arcuate cross section and extending downward, which are integrally formed. ing. Four bolt holes 45 are formed in the intermediate portion 43 of the cap body 41, the cap body 41 is attached to the tip of the valve shaft 19, and the four bolts 46 are inserted into the bolt holes 45 of the cap body 41 to insert the valve. The cap body 41 and the valve shaft 19 are connected to each other by screwing into the four screw holes 39 on the front end surface of the shaft 19. Support
Horizontal screw holes 47A on the lower end (base end) of 44A and 44B
47B is formed, and the male screws of the fulcrum rollers 49A and 49B are screwed and connected from the outside. As shown in FIG. 4, the supports 44A and 44B are located outside the bellows 37,
The non-contact state between the supports 44A and 44B and the bellows 37 is maintained. Although the valve shaft 19 and the cap body 41 are connected separately from each other here, the valve shaft 19 and the cap body 41 are connected to each other.
41 and 41 may be integrally formed, and in particular, the valve shaft 19 and the engaging portion 42 may be integrally formed.

The intermediate portion 43 of the cap body 41 has a valve shaft
Penetrating holes 50A and 50B are formed at positions facing the counterbore holes 38A and 38B of 19. Middle part of the cap body 41
Guide rod 51 at the positions on both sides of insertion holes 50A and 50B with 43
Screw holes 52A for connecting the lower ends (base ends) of A and 51B
52B is formed. As clearly shown in FIGS. 6 (a) and 7 (a), the movable plate 32 is provided with stepped guide elongated holes 53A and 53B, and the guide elongated holes 53A and 53B are provided with flanges. Guide rods 51A and 51B are slidably inserted. A male screw 54A is attached to the lower end of the guide rods 51A and 51B.
54B is formed, and the male screws 54A and 54B are screwed into the screw holes 52A and 52B of the cap body 41, and the cap body 41 is formed.
Is movably connected to the movable plate 32 so as not to be separated from the movable plate 32 by more than a set distance. A counterbored hole 55A for receiving the spring is provided on the lower side (back side) of the movable plate 32.
55B is formed, and the upper ends (tips) of the springs 57A and 57B are engaged with the counterbore holes 55A and 55B,
The lower ends (proximal ends) of 57A and 57B are insertion holes 50A of the cap body 41.
・ 38B of counterbore hole of the upper end surface of valve shaft 19 by inserting 50B
-It is engaged with 38B. As shown in FIG. 4, the spring 57
The valve shaft 19 can be moved to the movable plate 32 by the elastic force of A / 57B.
Receives the force in the direction away from, the flange of the guide rod 51A, 51B is fitted into the large diameter portion of the upper end of the elongated guide hole 53A, 53B,
The guide rods 51A and 51B do not project to the upper surface (front surface) of the movable plate 32.

A roller support member 59 is shown in FIGS. 6 (a) and 6 (b), and the roller support member 59 has an engaging portion at the upper end of the valve shaft 19.
Two engaging rollers 60A engaging with 42 (first engaging roller)
-Engagement roller 60B (second engagement roller) and four guide rollers 61A and 61C (front side guide roller) -Guide roller 61B
-61D (rear guide roller) is rotatably supported. The engagement rollers 60A and 60B are roller support members when viewed from the front.
It is located inside 59 and is rotatably supported by mounting bolts. The engagement roller 60A engages with the front surface 63 of the engagement portion 42, and the engagement roller 60B engages with the rear surface 64 of the engagement portion 42. The guide rollers 61A to 61D are arranged outside the roller support member 59 when viewed from the front, the guide rollers 61A and 61C are supported at the front end of the roller support member 59 by a common mounting bolt, and the guide rollers 61B and 61D are the roller support members. The guide roller 61 is supported on the rear end of the guide roller 59 by a common mounting bolt.
A to 61D are adapted to engage with receiving surfaces (68A, 68B) of a receiving table 70 described later. Two bolts 66 are inserted into the bolt holes 58A and 58B of the movable plate 32 and screwed into the screw holes 65A and 65B of the roller support member 59, respectively, and the roller support member 59 is fixed to the movable plate 32.

As clearly shown in FIG. 6B, the engaging roller 60A and the engaging roller 60B are separated from each other by a distance L in the vertical direction. Therefore, the engagement roller 60A is disposed on the front surface 63 of the engagement portion 42.
And the engaging roller 60B engages with the rear surface 64, the engaging position of the engaging roller 60B is below the engaging position of the engaging roller 60A by a distance L (toward the base end). . Engagement part
The front surface 63 and the rear surface 64 of 42 have parallel upper end side planes (front end side planes with respect to the axial center of the valve shaft 19) that are spaced apart by a predetermined front-rear distance, and the upper end side plane of the front surface 63 is slightly smaller than the upper end. This is the range, and the upper end side plane of the rear surface 64 extends downward by a distance L from the plane of the front surface 63. The shape of the front surface 63 has a short inclined portion in the direction of bulging forward following the upper end side plane, and the lower side of the inclined portion becomes a lower end side plane (a base end side plane parallel to the axial center of the valve shaft 19) 63A. ing. The shape of the rear surface 64 has a short inclined portion in the direction of being recessed forward following the flat surface of the upper end, and the lower surface of the inclined portion is the lower end side flat surface 64A. The lower end side flat surface 63A of the front surface 63 and the lower end side flat surface 64A of the rear surface 64 function as an inclined surface (wedge surface) when inclined by θ ° as shown in FIG.

1, 2 and 4, the engaging roller 60A engages with the upper end portion of the upper surface of the front surface 63, and the engaging roller 60B engages with the central portion of the upper surface of the rear surface 64. Together,
The engaging portion 42 is sandwiched by the engaging roller 60A and the engaging roller 60B from the front-rear direction. By this clamping, the cap body 41 and the valve shaft 19 are grasped, and the valve shaft
Prevents 19 rolling in the front-back direction. The left and right ends of the upper end surface of the valve shaft 19 have two springs 57A and 57A.
It is being pressed by B, and this pressing causes the valve shaft
The horizontal roll of 19 is prevented.

A cradle 70 is shown in FIGS. 7 (c)-(e). As shown in FIG. 7 (c), the pedestal 70 has a shape in which the front portion and the rear portion of the thick-walled cylinder are removed in a top view, and there is a space for inserting the valve shaft 19 and the bellows 37 in the center. . Cradle
Flat plate-shaped receiving portions 69A and 69B are formed at the front and rear end portions over the entire length from the upper end (tip) of 70 to about 1/3 of the whole, and a flat receiving surface is provided inside the receiving portions 69A and 69B. 68A (first
A receiving surface) and a receiving surface 68B (second receiving surface) are formed. Receiving surface
A roller support member 59 is inserted between 68A and the receiving surface 68B, and at that time, guide rollers 61A and 61C of the roller support member 59 are inserted.
Comes into contact with the receiving surface 68A, and the guide rollers 61B and 61D receive the receiving surface 68B.
To be in contact with. At the left and right ends of the cradle 70,
Two vertically elongated fulcrum grooves 72A and 72B with open ends are formed, and the upper ends of the fulcrum grooves 72A and 72B are horizontal portions 71A to 71D.
Are connected to the lower portions of both ends of the receiving surfaces 68A and 68B via.
The length of the fulcrum groove 72A / 72B is 1/3 of the height of the pedestal 70 as a whole, and the fulcrum roller 49A / 49B of the cap body 41 is inserted into the fulcrum groove 72A / 72B, and the fulcrum roller 49A / 49B is inserted. Are set to be supported by the lower ends of the fulcrum grooves 72A and 72B. A bolt hole 73 extending from the horizontal portions 71A to D to the lower end is formed, and the bolt hole 73 is inserted and screwed into the screw hole of the support wall 26 to fix the pedestal 70 to the support wall 26.

The operation of the embodiment of the gate valve of the present invention will be described. In the valve fully opened state of FIG. 1, the output member 31 is located at the rising stroke end of the drive device 28, and the movable plate 32 is located at the rising end while maintaining a non-contact state with the connecting member 29. In addition, the guide rod 51A
The movable plate 32, the cap body 41 and the valve shaft 19 are connected by 51B so as not to be separated from each other by a predetermined distance or more, and the elastic forces of the springs 57A and 57B act so as to be separated by a predetermined distance. Therefore, in the state shown in FIG. 1, a predetermined distance is maintained between the movable plate 32 and the cap body 41 / valve shaft 19. When this predetermined distance is maintained, the engaging roller 60A of the roller supporting member 59 is engaged with the engaging portion 42A.
Is engaged with the upper end position of the upper end side plane of the front surface 63 (the position on the upper end side by a play distance from the inclined portion), and the engagement roller 60B is attached to the rear surface 64.
The cap body 41 is gripped by the engaging rollers 60A and 60B by engaging with the center position of the upper end side plane (position on the upper end side by a play distance from the inclined portion).

The left and right ends of the movable plate 32 are connected to the guide cylinder 33 and the output member 31 by bolts. When the output member 31 descends (advances), the movable plate 32 and the valve shaft 19 are separated from each other by the predetermined distance. The gate 18 moves downward and rectilinear while keeping the same, and the gate 18 moves toward the valve closing direction. When the valve shaft 19 moves down and goes straight, the engagement roller 60A
Since the engaging portion 42 is clamped by 60B, the valve shaft
There is no sway in the front-back direction of 19, and springs 57A and 57B
Since the left and right ends of the upper end surface of the valve shaft 19 are pressed by the valve shaft 19, the valve shaft 19 does not swing in the left-right direction. Further, when the valve shaft 19 makes a descending / straightening motion, the outer peripheral surface of the valve shaft 19 does not come into contact with the bellows 37 / guide ring 35. Further, since the predetermined distance is maintained, the engaging rollers 60A and 60B do not engage with the inclined portions of the front surface 63 and the rear surface 64 of the engaging portion 42 during the descending / straightening motion.

In the latter half of the downward stroke of the valve shaft 19, the fulcrum rollers 49A and 49B of the cap body 41 are received by the pedestal 70.
Entering the vertically long fulcrum grooves 72A and 72B, the front-back positioning of the roller support member 59 is accurately performed. Next, the guide rollers 61A to 61D of the roller support member 59 are received on the receiving surface 68A of the receiving table 70.
It engages 68B snugly and descends a little further to the end of the descending stroke of valve shaft 19. At the end of the descending stroke, the fulcrum rollers 49A and 49B come into contact with the lower ends (proximal ends) of the fulcrum grooves 72A and 72B, and the valve shaft 19 and the cap body.
41 descent stops. In this way, the valve shaft 19
The cap body 41 and the gate 18 reach the descending end position (gate descending position in FIG. 2). At this time, the engaging roller 60A engages with the upper end position of the upper surface of the front surface 63 of the engaging portion 42 (the position on the upper end side by the play distance from the inclined portion), and the engaging roller 60B has the upper surface of the rear surface 64. Is engaged at the center position (the position on the upper end side by the play distance from the inclined portion).

Even when the valve shaft 19 and the cap body 41 reach the descending end position, the output member 31 and the roller supporting member 59 continue the descending motion, and descend against the elastic force of the springs 57A and 57B. To do. When the roller support member 59 moves down and goes straight by the play distance, the engagement roller 60A reaches the inclined portion of the upper end side plane of the front surface 63, and the engagement roller 60A descends along the inclined portion to move the cap body. 41 ・ Tilt the valve shaft 19,
Then, it descends along the lower end side flat surface 63A engaging as a slope. At this time, the engaging roller 60B descends substantially along the inclined portion of the rear surface 64, and then engages as a sloped lower end side flat surface 64.
It descends almost along A. When the engagement roller 60A descends while engaging with the surface of the inclined portion / lower end side flat surface 63A (both are collectively referred to as an inclined surface portion), the valve shaft 19 is a fulcrum roller.
Swing centering around 49A and 49B to seal the gate 18
20 is pressed against the valve seat 24 of the front wall 22 to reach the valve fully closed state shown in FIG.

The reaction force of the pressing force is transmitted to the receiving surface 68A of the pedestal 70 by the guide rollers 61A and 61C of the roller supporting member 59, and is received by the receiving surface 68A. When the engagement roller 60A descends while engaging with the surface of the inclined portion / lower end side flat surface 63A (both are collectively referred to as an inclined surface portion), as shown in FIG. 5, the valve shaft 19 moves toward the center line X of the valve body 11. Θ for −X
° It will be inclined. Therefore, the sealing member of the gate 18
The pressing force of 20 is the force of the roller support member 59 in the descending direction (generally from the driving force of the driving device 28 to the springs 57A and 57B).
(1 / tan θ °) times the value obtained by subtracting the force against), and the driving force is expanded by the wedge effect when descending while engaging with the inclined portion / lower end side flat surface 63A. θ
The smaller the angle is, the larger the driving force is, and the longer the distance moved for the expansion becomes, and the smaller the driving device 28 can be made. Note that θ ° is not constant, and the angle increases as the engagement roller 60A descends.

When the valve shaft 19 and the cap body 41 reach the lower end position, the guide rods 51A and 51B cannot be further lowered, but the roller support member 59 and the movable plate 32 are lowered, so that the guide rods 51A and 51B are movable. It projects upward from the upper end side of the plate 32. Then, as shown in FIGS. 7 (a) and 7 (b), the guide rod is swung simultaneously with the guide rod.
Since 51A and 51B also oscillate, the oblong holes 53A and 53B for guide are elongated in the front-rear direction so as not to interfere with the oscillating movement. Due to the existence of the play distance, the fulcrum rollers 49A and 49B come into contact with the lower ends of the fulcrum grooves 72A and 72B, and the downward movement of the valve shaft 19 is stopped, and the engaging roller 60A is engaged with the engaging portion 42. There is a time interval between the point of contact with the inclined portion of the front surface 63 and the start of swinging. Therefore, the time of occurrence of impact is dispersed, and the impact is alleviated.

When the valve is fully closed in FIG. 3, the lower surface of the output member 31 comes into contact with the upper surface of the swing amount adjusting member (stopper) 75, and the downward movement of the output member 31 and the roller support member 59 is stopped. The pressing force of the seal member 20 of the gate 18 is limited to the required amount. It is configured such that the position of the upper surface of the swing amount adjusting member 75 can be adjusted up and down to change the position in contact with the output member 31.

When it is desired to change the valve from the fully closed state (see FIG. 3) to the gate descending state (see FIG. 2), the output member
31 ・ The roller support member 59 is moved upward (backward) or in a straight line. The elastic force of the springs 57A and 57B is generated by the engaging rollers 60A and 60B of the roller supporting member 59.
The cap body 41 rises while sandwiching the front surface 63 and the rear surface 64 of the
It is set to be larger than the total of the force for pulling up the engaging portion 42 and the weight of the gate 18. Therefore, the roller support member 59
When it is raised and moved straight, the cap body 41 and valve shaft
19. The fulcrum rollers 49A and 49B are maintained at the lower end position by the elastic force of the springs 57A and 57B, and the engagement roller 60B is located along the lower surface 64A of the rear surface 64 of the engaging portion 42 of the cap body 41 and the inclined portion. Rise to reach the upper end side plane. Engaging roller 60A
Rises almost along the inclined portion of the lower end side flat surface 63A / front surface 63, and then reaches the upper end side flat surface. When the engaging roller 60B moves up while engaging with the lower end side flat surface 64A and the surface of the inclined portion, the valve shaft 19 swings about the fulcrum rollers 49A and 49B located at the lower ends of the fulcrum grooves 72A and 72B. The sealing member 20 of the gate 18 is separated from the valve seat 24 of the front wall 22 to reach the gate descending state shown in FIG.

The reaction force of the separating force is smaller than the reaction force of the pressing force described above, and the guide rollers 61B and 61B of the roller supporting member 59.
It is transmitted to the receiving surface 68B of the receiving table 70 by D and received by the receiving surface 68B. When the engaging roller 60B starts to move upward while engaging with the lower end side flat surface 64A and the surface of the inclined portion, the valve shaft 19 is θ ° with respect to the center line XX of the valve body 11, as shown in FIG. It is inclined. Therefore, the sealing member of the gate 18
The separating force of 20 is (1) of the force of the roller supporting member 59 in the ascending direction.
/ Tan θ °) times larger, and the driving force is expanded by the wedge effect when rising while engaging with the lower end side flat surface 64A / inclined portion.

When it is desired to change the valve from the separated state (see FIG. 2) to the fully opened state (see FIG. 1), the output member 31 and the roller support member 59 are moved upward and straight. Output member 31
Similar to the case where the roller support member 59 is caused to move downward and rectilinearly, the valve shaft 19 moves up without swinging in the front-rear direction and without swinging in the left-right direction. The outer peripheral surface of the valve shaft 19 does not come into contact with the bellows 37 and the guide ring 35 when the valve shaft 19 moves up and goes straight. Further, the engaging rollers 60A and 60B do not engage with the inclined portions of the front surface 63 and the rear surface 64 of the engaging portion 42 during the ascending / straightening motion. The above description is based on the premise that the gate valve is upright in the vertical direction as shown in FIGS. 1 to 3. However, even if the mounting posture of the gate valve is turned upside down or sideways, it is upright. Works the same as when.

[0025]

According to claims 1 to 3 of the present invention,
The valve shaft is inserted in the center hole of the support wall of the valve body in a non-contact state, the side surface of the valve shaft outside the valve chamber is covered in a non-contact state by the bellows, and the space between the tip of the bellows and the tip of the valve shaft is airtight. The bellows is kept airtight between the base end of the bellows and the periphery of the central hole of the support wall. In this way, since there is no sliding portion in the sealed space inside the valve chamber and the bellows, it is possible to prevent the generation of particles that cause contamination.

According to the fourth to eighth aspects of the present invention, after the gate reaches the facing position of the valve seat by the rectilinear motion of the valve shaft, the roller support member is moved forward so that the first engaging roller engages with the valve shaft tip. By engaging with the slope on the front of the joint, the linear motion of the drive member is converted into swinging motion with the fulcrum roller of the gate as the fulcrum, and the valve shaft swings and presses the gate against the valve seat. It is supposed to be. Since the slope is used when the rocking motion is performed, a wedge effect is generated, a small force can be expanded to perform the rocking motion, and the gate driving unit can be downsized.

[Brief description of drawings]

FIG. 1 shows a fully opened state of an embodiment of a gate valve of the present invention, FIG. 1 (a) is a front view, and FIG.
2 is a sectional view taken along line BB of FIG. 1 (a).

FIG. 2 shows a gate descending state of the embodiment of the gate valve of the present invention, FIG. 2 (a) is a front view, and FIG.
2 is a sectional view taken along line BB of FIG. 2 (a).

FIG. 3 shows a fully closed state of a gate valve according to an embodiment of the present invention, FIG. 3 (a) is a front view, and FIG.
FIG. 4 is a sectional view taken along the line BB of FIG.

4 (a) is an enlarged view of a main part of FIG. 2 (a).
(b) is an enlarged view of the main part of FIG. 2 (b).

5 is an enlarged view of a main part of FIG. 3 (b).

6 (a) is an exploded front view of main parts of an embodiment of a gate valve of the present invention, FIG. 6 (b) is a side view of a roller supporting member, and FIG. 6 (c) is a cap body. Side view of FIG.
6D is a top view of the cap body, and FIG. 6E is a top view of the valve shaft.

7 (a) is a top view of a movable plate used in the embodiment of the gate valve of the present invention, and FIG. 7 (b) is FIG.
7A is a cross-sectional view taken along line YY, FIG. 7C is a top view of a pedestal used in the embodiment of the gate valve of the present invention, and FIG. 7D is ZZ of FIG. 7C. FIG. 7 (e) is a side view of the pedestal shown in FIG. 7 (c).

[Explanation of symbols]

 11 Valve body 14 1st opening 15 2nd opening 16 Valve chamber 18 Gate 19 Valve shaft 22 Front wall 23 Rear wall 24 Valve seat 26 Support wall 32 Movable plate 35 Guide ring 36 Flange 37 Bellows 42 Engaging part 49A / 49B For fulcrum Roller 51A / 51B Guide rod 57A / 57B Spring 59 Roller support member 60A First engaging roller 60B Second engaging roller 61A / 61C Front guide roller 61B / 61D Rear guide roller 68A First receiving surface 68B Second receiving surface 70 Cradle 72A / 72B fulcrum groove

Claims (8)

[Claims] 1. A valve body having a valve chamber inside, a first opening and a second opening are formed in a front wall and a rear wall, respectively, and a valve seat is formed inside the first opening or the second opening. In a gate valve in which a gate is connected to the base end of a valve shaft that performs the above-mentioned operation and the gate is pressed against the valve seat to close the valve, the valve shaft is inserted into the central hole of the support wall of the valve body in a non-contact state. The side surface of the valve shaft outside the valve chamber is covered by the bellows in a non-contact state, and the tip of the bellows and the tip portion of the valve shaft are made airtight, and the base end of the bellows and the center hole of the support wall are The gate valve is characterized in that the space between the two is made airtight. 2. A bellows, wherein a guide ring is fitted in a central hole of the support wall, the valve shaft is inserted into the guide ring so as to maintain a non-contact state, and a flange is integrally formed at a tip end portion of the valve shaft. 2. The gate valve according to claim 1, wherein a front end of the bellows is fixed to the back surface of the flange in an airtight state, and a base end of the bellows is fixed to the guide ring in an airtight state. 3. A first engagement roller and a second engagement rotatably supported by a roller support member, wherein an engagement portion having a front surface and a rear surface is formed at the tip of the valve shaft integrally or separately from the valve shaft. The front and rear surfaces of the engaging portion are sandwiched by rollers, the movable plate is guided so as to perform a rectilinear motion, the roller support member is fixed to the movable plate, and the left and right ends of the valve shaft front end surface and the movable plate are connected. The gate valve according to claim 1, wherein a spring is mounted between the gate valve and the gate valve. 4. A valve body having a valve chamber inside, a first opening and a second opening are formed in a front wall and a rear wall, respectively, and a valve seat is formed inside the first opening or the second opening. In a gate valve in which a gate is connected to the base end of the valve shaft to press the gate against the valve seat to close the valve, after the gate shaft reaches the opposite position of the valve seat by the rectilinear motion of the valve shaft. The gate valve is characterized in that the gate is pressed against the valve seat by the swing motion of the valve shaft. 5. A first engaging roller and a second engaging roller rotatably supported by a roller supporting member, wherein an engaging portion having a front surface and a rear surface is formed at the tip of the valve shaft integrally or separately from the valve shaft. When the fulcrum roller connected to the front end of the valve shaft is supported at the base end of the fulcrum groove, the front and rear surfaces of the engaging portion are engaged by the rollers, and the roller support member is moved forward to 3. A valve shaft is configured to swing in a direction in which a gate is pressed against a valve seat by engaging a first engaging roller with a sloped portion of the front surface.
And the gate valve according to any one of 4 above. 6. The valve shaft separates the gate from the valve seat when the gate is pressed against the valve seat by retracting the roller support member so that the second engaging roller engages with the rear slope. The gate valve according to claim 5, wherein the gate valve is configured to swing in a direction. 7. A pedestal is fixed to a support wall of the valve body, a longitudinal fulcrum groove into which a fulcrum roller is inserted is formed in the pedestal, and a first receiving surface and a second receiving surface are formed. 7. The gate valve according to claim 5, wherein a front guide roller and a rear guide roller, which are rotatably supported by a roller support member, are engaged with the first receiving surface and the second receiving surface, respectively. 8. The movable plate is guided so as to perform a rectilinear movement, the roller support member is fixed to the movable plate, and the tip of the valve shaft and the movable plate are not separated by a guide rod beyond a set distance. Connected as
A spring is mounted between the left and right ends of the valve shaft front end surface and the movable plate, and the engaging portion of the valve shaft is held by the first engaging roller and the second engaging roller. Gate valve described in one.