JP2003042310A - Gate valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gate valve certainly preventing a by-product from adhering to a seal portion, and having high reliability with a simple structure. SOLUTION: This gate valve 10 comprises a gate portion 18 rocking between a close position P1 and an open position P2, a pressing mechanism 30 enabling a seal material 26 provided on the gate portion 18 to tightly contact with a first seal surface 28a provided at the close position P1 so as to surround through holes 14a, 14b and a second seal surface 28b provided at the open position P2 by displacing the gate portion 18 to side wall portions 12a, 12b of a valve casing 16, and an actuating mechanism 32 rocking the gate portion 18 and energizing the pressing mechanism 30 at the close position P1 and the open position P2 to displace the gate portion 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gate valve capable of opening and closing an opening provided in a valve box under the action of a gate section provided in the valve box.

[0002]

2. Description of the Related Art For example, an exhaust circular gate valve is used in a high-purity gas system or an ultra-high vacuum system such as a semiconductor manufacturing apparatus. This type of gate valve includes a straight type system in which a through hole formed in a valve box is opened and closed by a linear movement of a valve plate, and a pendulum type system in which the valve plate is swung to open and close the through hole. .

As the pendulum type gate valve, for example, a dust-free gate valve disclosed in Japanese Patent Laid-Open No. 347084/1992 is known. In this prior art, as shown in FIG. 10, a valve assembly 3 for opening and closing a through hole 2 provided in the valve box 1 is swingably arranged in the valve box 1. The valve assembly 3 includes the valve assembly 3
An opening / closing actuator 4 that swings between a closed position corresponding to the through hole 2 and an open position separated from the through hole 2, and an expansion / contraction actuator capable of expanding / contracting the valve assembly 3 to close the through hole 2. And 5 are connected.

[0004]

In the above prior art, in the closed position, the valve member constituting the valve assembly 3 is expanded so that the seat surface of the valve member is arranged around the through hole 2. It is in close contact with the seal material. Accordingly, the seat surface of the valve member and the seal surface and the outside of the seal material are not exposed to the exhausted gas, and the clean state of the seat surface and the seal material can be maintained in good condition.

However, when the valve assembly 3 is placed in the open position, the valve assembly 3 is contracted, and the seat surface of the valve member is separated from the inner surface of the valve box 1. Therefore, the seat surface of the valve member is exposed to the exhausted gas, and by-products contained in the exhausted gas are likely to adhere to the seat surface. It has been pointed out that this causes a by-product to intervene between the sheet surface and the sealing material, causing a leak from the through hole 2.

Therefore, for example, Japanese Patent Laid-Open No. 5-164255.
It is possible to adopt the gate valve disclosed in the publication. In this conventional technique, the valve plate is a flat valve closing portion that faces a through hole provided in the valve box and closes the through hole,
And a valve opening portion that holds the valve opened state by an opening that is substantially the same in shape as the through hole.

Then, the valve closing portion of the valve plate is brought into pressure contact with the sealing material arranged around the through hole to close the through hole, while the valve plate is swung, and then the valve opening of the valve plate is performed. The portion is pressed against the sealing material to open the through hole. As described above, since the valve plate is in close contact with the valve box in the state where the valve plate is placed in the closed position and the open position, even if the through holes communicate with each other, the valve closing part and the opening part of the valve plate are closed. The valve is not exposed to the exhausted gas.

However, in the above-mentioned prior art, the valve plate is provided with the valve closing portion and the valve opening portion, and it is necessary to set the area of this valve plate to be approximately twice the area of a normal valve plate. . Therefore, in order to swing the valve plate in the valve box, the volume of the valve box needs to be about 1.5 times that of the valve box of a normal gate valve, and the occupied space of the gate valve increases. At the same time, it has been pointed out that the manufacturing cost rises.

The present invention solves this type of problem by reliably preventing by-products from adhering to the seal portion, effectively simplifying maintenance and the like, and achieving high reliability and downsizing. The purpose of the present invention is to provide a gate valve suitable for.

[0010]

In the gate valve according to the present invention, the gate portion provided in the valve box corresponds to the through hole provided in the side portion of the valve box under the action of the operating mechanism. After being placed in the closed position, the gate portion is displaced (expanded) to the side of the valve box. For this reason, the seal part provided in the gate part is provided in the closed position so as to surround the through hole.
The through hole can be surely closed by closely contacting the sealing surface.

On the other hand, under the action of the actuating mechanism, the gate portion swings to be placed in the open position, and then the gate portion is displaced to the side of the valve box via the actuating mechanism. Therefore, the seal part provided on the gate part is
Stick to the sealing surface.

As a result, the seal portion provided on the gate portion is in close contact with the first seal surface when it is placed in the closed position, and is in close contact with the second seal surface when it is placed in the open position. Especially, in the open position, the entire surface of the seal portion is not exposed to the gas flowing through the through hole. For this reason, by-products contained in the gas do not adhere to the surface of the seal portion, and it is possible to reliably prevent the leakage of gas at the closed position due to these by-products, and to prevent the entire gate valve from leaking. It is possible to reduce the size.

Further, the pressing mechanism includes an axis member which has an axis line passing through the axis of the support shaft and intersecting the axis line, and which moves the gate portion in the axial direction to displace the gate portion, and the actuating mechanism has a single shaft. An actuator, an actuating member that engages with the actuator and is movable back and forth, and the shaft member is swung between an open position and a closed position, and the shaft member is advanced and retracted in the axial direction at the closed position and the open position. And a cam structure that allows it.

As described above, the drive for swinging the shaft member between the closed position and the open position and the drive for moving the shaft member forward and backward in the closed position and the open position are performed by a single actuator. Therefore, the gate valve as a whole can be effectively reduced in size and can be manufactured at low cost, as compared with the conventional technique in which each drive is performed by an individual actuator. Therefore, while reducing the manufacturing cost of the gate valve,
It is possible to narrow the space occupied by the gate valve. Moreover, the signal system is unified, which is economical, and the relay and the like are not required, so that the reliability can be improved.

Further, a pipe member which is inserted into the shaft member such that the shaft member can be moved forward and backward and is swingable around a support shaft, a closing member which abuts on the pipe member and holds the gate portion in a closed position and an open position, and Surrounding the pipe member and fixed to the gate portion and the valve box,
And a bellows member capable of hermetically sealing the inside of the valve box. Therefore, the pipe member is held in the closed position and the open position via the closing member, and the shaft member can be reliably advanced and retracted in the pipe member to easily and reliably advance and retract the gate portion. Further, by using the bellows member, the inside of the valve box can be hermetically sealed with a simple structure.

Furthermore, the cam structure has a roller provided on the shaft member, a swing groove provided on the actuating member, into which the roller is inserted, and provided on the actuating member in communication with both sides of the swing groove. And a first and a second seal groove into which the roller is inserted. When the operating member moves back and forth, the roller is arranged in the swing groove to swing the shaft member, while the roller moves along the first and second seal grooves at the closed position and the open position. As a result, the seal portion of the gate portion comes into close contact with the first and second seal surfaces. Accordingly, with a simple configuration, the swinging movement and the forward / backward movement of the shaft member can be smoothly performed under the forward / backward movement of the operating member.

Further, a pair of linear guides are provided on both sides of the actuating member so as to extend in the advancing / retreating direction of the actuating member in order to receive loads acting in the vertical and horizontal directions. Therefore, the forward / backward movement of the operating member is surely performed, and the gate valve can be accurately driven and controlled.

[0018]

1 is a sectional front view of a gate valve 10 according to a first embodiment of the present invention, and FIG.
3 is a sectional side view of the gate valve 10. FIG.

The gate valve 10 has two side wall portions 12a, 1
2b is provided with a valve box 16 having through holes 14a and 14b formed therethrough, and inside the valve box 16, a gate portion 18 capable of opening and closing the through holes 14a and 14b is arranged. Gate 18
Is provided with a pair of valve plates 22 which are swingable around the support shaft 20 between a closed position P1 corresponding to the through holes 14a and 14b and an open position P2 spaced apart from the through holes 14a and 14b.

The gate valve 10 is provided with a shaft member 24 having an axis passing through the axis of the support shaft 20 and intersecting the axis, and the gate member 18 is moved forward and backward in the axial direction (direction of arrow A). Is expanded or contracted (displaced) toward both side wall portions 12a and 12b, so that the sealing material 26 provided on the valve plate 22 is provided at the closed position P1 so as to surround the through holes 14a and 14b. And a pressing mechanism 30 that can be in close contact with the second seal surface 28b provided at the open position P2,
The gate unit 18 is swung about the support shaft 20 as a fulcrum, and the actuating mechanism 32 is provided to urge the pressing mechanism 30 at the closed position P1 and the open position P2 to expand and contract the gate unit 18.

A storage chamber 34 is provided in the valve box 16 in correspondence with the open position P2, and a base portion 36 is attached to the upper portion of the valve box 16, and a pair of spindles is attached to the base portion 36. 20 are provided. Each of the support shafts 20 is fixed to the outer peripheral surface of the pipe member 38 in a state of being arranged in the diameter direction of the pipe member 38, and the shaft member 24 is movable in the pipe member 38 in the arrow A direction. Is inserted.

As shown in FIG. 2, the end portion of the pipe member 38 is
The ring 40 is fixed to the outer peripheral portion of the ring 40 that constitutes the gate portion 18, and the ring 40 is fitted onto the joint portion of the pair of valve plates 22. The ring 40 has a guide function when the valve plates 22 are separated from each other or joined to each other.
And the valve plate 22 are connected via a bellows member 42.

As shown in FIG. 1, the base portion 36 is provided with a closing member 44, and the pipe member 38 contacts the closing member 44 to hold the valve plate 22 in the closed position P1 and the open position P2. The ring 40 that constitutes the gate portion 18 and the valve box 16
Both ends of a bellows member 46, which surrounds the pipe member 38 and can hermetically seal the inside of the valve box 16, are fixed to (or the base portion 36). Via the bellows members 42, 46,
The fluid flow path inside the valve box 16 and the inside of the gate portion 18 are completely isolated, and a dust-free structure inside the valve box 16 is realized.

As shown in FIG. 2, the pressing mechanism 30 is provided at the end portions of the shaft member 24 inserted between the taper portions 48 provided on the opposite surface sides of the two valve plates 22, respectively. The spherical rolling element 50 is provided. The tapered portion 48 is inclined inward toward the arrow A1 direction, and when the shaft member 24 moves in the arrow A1 direction, the rolling element 5
0 contacts the tapered portion 48 to displace the valve plates 22 in the direction in which they are separated from each other, that is, the gate portion 18
Is configured to extend.

A spring seat 52 is provided on the upper end side of the shaft member 24, and a spring member 54 is interposed between the spring seat 52 and a spring seat 53 provided on the upper end surface of the pipe member 38.
At the upper end of the shaft member 24, the rod 56 intersects with the axial direction.
Are fixed, and rollers 58, which constitute a cam structure 84 described later, are arranged at both ends of the rod 56.

As shown in FIG. 1, the operating mechanism 32 is a single cylinder (actuator) fixed to a base 36.
A cylinder chamber 64 in the cylinder 62 is in communication with air ports 66 and 68. Cylinder chamber 64
The piston rod 72 extending from the piston 70 arranged in the above direction extends in the direction of arrow B1 and the actuating member 74 is fixed to the tip portion thereof.

As shown in FIG. 2, the operating member 74 is formed in a gate shape, and both side portions 76 of the operating member 74 receive the loads acting in the vertical direction and the horizontal direction. A pair of linear guides 78 are arranged to extend in the advancing / retreating direction of the actuating member 74 (the direction of arrow B in FIG. 1).
Each of the linear guides 78 is provided on the base portion 36, and a V-shaped groove portion 80 is formed on the inner surface portion facing each other. A V-shaped groove portion 82 is formed on both side portions 76 of the actuating member 74, and a plurality of spheres 83 are arranged between the V-shaped groove portions 80, 82.

The shaft member 24 is attached to the operating member 74 at the open position P.
2 and the closed position P1 and the closed position P
1 and a cam structure 84 that advances and retracts the shaft member 24 in the arrow A direction at the open position P2. Cam structure 84
Are provided on both sides 76 of the actuating member 74, and
And a first and second seal grooves 92a and 92b, which are provided on the operating member 74 and communicate with both sides of the swing groove 90, and into which the roller 58 is inserted.

The swing groove 90 is constituted by an arc-shaped swing surface 94 for supporting the roller 58 by sliding contact with the peripheral surface of the roller 58 when the shaft member 24 swings around the support shaft 20. Has been done. First and second seal grooves 92a, 92b
Indicates that the shaft member 24 has an arrow A at the closed position P1 and at the open position P2.
The first and second inclined surfaces, which allow the movement of the roller 58 when moving forward and backward in the direction, and which incline a predetermined angle vertically downward from the horizontal direction in a direction in which they are separated from each other with the swing surface 94 as the apex. It is composed of 96a and 96b.

The operation of the gate valve 10 thus constructed will be described below.

As shown in FIG. 3, when the gate portion 18 is arranged in the storage chamber 34 corresponding to the open position P2, the valve box 1
Through hole 14 formed in the side wall portions 12a and 12b
a and 14b are in communication with each other. Therefore, for example, a vacuum chamber (not shown) and a vacuum pump communicate with each other,
Exhaust treatment is being performed.

Therefore, when the through holes 14a and 14b are closed, as shown in FIG. 3, first, air is supplied to the air port 68 constituting the cylinder 62 and exhausted from the air port 66, so that the operating member is operated. 74 moves in the direction of arrow B1. At that time, the spring seat 53 provided on the pipe member 38.
Due to the elastic force of the spring member 54 interposed between the spring seat 52 fixed to the shaft member 24 and the spring seat 52 fixed to the shaft member 24, the roller 58 provided on the shaft member 24 causes the swing groove 90 forming the cam structure 84. It is held on the inner swing surface 94. Therefore,
When the operating member 74 moves in the direction of arrow B1, the shaft member 24
And the pipe member 38 is opened position P2 centering | focusing on the spindle 20.
The roller 58 is supported in the swing surface 94 while swinging from the closed position P1 side.

When the actuating member 74 further moves in the direction of arrow B1 via the cylinder 62, the pipe member 38 comes into contact with the closing member 44, so that the swinging motion of the pipe member 38 is stopped (see FIG. 1). . In this state, when the operating member 74 moves in the direction of the arrow B1, the roller 58 moves from the swing surface 94 along the first inclined surface 96a of the first seal groove 92a while compressing the spring member 54, and the roller 58 moves. The shaft member 24 provided with moves the inside of the pipe member 38 in the arrow A1 direction (see FIG. 4).

Therefore, as shown in FIG. 5, the shaft member 24
Moves in the direction of arrow A1, and the rolling element 50 forming the pressing mechanism 30 moves in the direction of arrow A1 integrally with the shaft member 24 and abuts on the tapered portion 48. Thereby, the valve plate 22
Move under the action of the rolling element 50 and the tapered portion 48 in a direction in which they are separated from each other (expansion of the gate portion 18), and the respective seal members 26 form the side wall portions 12 a, 12 of the valve box 16.
It comes into close contact with the first sealing surface 28a provided at b, and the through holes 14a and 14b are reliably closed.

On the other hand, the through holes 14a, 1 by the gate portion 18
When the blockage of 4b is released, high-pressure air is supplied to the air port 66 of the cylinder 62, and the operating member 74 connected to the piston rod 72 moves in the arrow B2 direction.
At that time, the shaft member 24 is connected to the arrow A through the spring member 54.
The pressing force acting in two directions acts, the roller 58 rises along the first inclined surface 96a, and the shaft member 24 provided with this roller 58 moves in the arrow A2 direction. Therefore, the rolling element 50 provided on the shaft member 24 is disengaged from the taper portion 48, and the valve plates 22 are displaced in a direction in which they are close to each other (contraction of the gate portion 18), and the through hole 14a by the gate portion 18 is formed. , 14b are released.

Then, the roller 58 is attached to the first seal groove 92a.
When the roller 58 is moved from the swing groove 90 to the swing groove 90, the contraction of the gate portion 18 is completed, and as the actuating member 74 moves in the arrow B2 direction, the roller 58 is placed in the swing groove 90 in the arrow B2 direction. Move to. Therefore, the shaft member 24 and the pipe member 38 start swinging about the support shaft 20, and the gate portion 1
8 is stored in the storage chamber 34 corresponding to the open position P2.

Further, when the cylinder 62 is driven in the direction of arrow B1, the pipe member 38 is supported by contact with the closing member 44, so that when the actuating member 74 further moves in the direction of arrow B2, the roller 58 causes the spring member to spring. Swing surface 9 while compressing 54
4 to move along the second inclined surface 96b of the second seal groove 92b.

Therefore, the shaft member 24 having the roller 58 is provided.
Moves in the direction of arrow A1 in the pipe member 38, and the pressing mechanism 30
Is driven to move the valve plates 22 in a direction in which they are separated from each other,
The gate portion 18 is expanded. Therefore, the sealing material 26 provided on the valve plate 22 comes into close contact with the second sealing surface 28b provided on the side wall portions 12a and 12b forming the valve box 16.

As a result, the through holes 14a, 14 of the valve box 16 are formed.
b communicates with each other, a vacuum chamber (not shown) and a vacuum pump communicate with each other between the through holes 14a and 14b, and the exhaust process is restarted.

As described above, in the first embodiment, the cylinder 62 constituting the operating mechanism 32 is driven, and the operating member 7
When 4 moves in the direction of arrow B1, first, the shaft member 2 is moved under the action of the swing groove 90 and the roller 58 forming the cam structure 84.
4 swings, and the gate portion 18 moves from the open position P2 to the closed position P.
Swing to 1.

Then, the shaft member 24 moves in the direction of arrow A1 under the action of the roller 58 and the first seal groove 92a forming the cam structure 84, and the valve plates 22 are separated from each other via the pressing mechanism 30. Move (expand) to the gate section 18
The through holes 14a and 14b of the valve box 16 are sealed by the above.

On the other hand, under the action of the operating mechanism 32, the gate portion 1
When the gate portion 18 is placed at the open position P2 by swinging the shaft 8, the shaft member 24 moves in the direction of the arrow A1 under the action of the roller 58 and the second seal groove 92b forming the cam structure 84. , The valve plates 22 move in a direction in which they are separated from each other via the pressing mechanism 30. Therefore, the gate portion 18 expands,
The sealing material 26 provided on the gate portion 18 is the second
It comes into close contact with the sealing surface 28b.

As a result, in the first embodiment, when the sealing material 26 provided on the gate portion 18 is arranged at the closed position P1, the sealing material 26 comes into close contact with the first sealing surface 28a and the through hole. Seal 14a and 14b. On the other hand, when the sealing material 26 is placed in the open position P2, the sealing material 2
6 is in close contact with the second sealing surface 28b.

Therefore, especially at the open position P2, the outer diameter end of the sealing material 26 is not exposed to the gas flowing through the through holes 14a and 14b, and the surface of the sealing material 26 is contained in the gas. By-products do not adhere. Therefore, when the gate portion 18 is arranged at the closed position P1 again and the sealing material 26 is brought into contact with the first sealing surface 28a, the through-holes 14a through the by-products attached to the sealing material 26,
It is possible to reliably prevent the gas leak from 14b.

Moreover, gas leakage from the through holes 14a and 14b due to the by-products adhering to the sealing material 26 is prevented, so that the maintenance cycle of the gate valve 10 is remarkably extended and the workability is improved. To be At that time, the by-product does not adhere to the sealing material 26, the generation of dust due to the separated by-product is reliably prevented, and a clean vacuum device can be reliably provided.

Further, in the first embodiment, the gate portion 18
The swinging movement of the gate valve 18 and the expanding / contracting movement of the gate portion 18 are performed via a single cylinder 62, so that the entire gate valve 10 can be effectively miniaturized as compared with the prior art in which each drive is performed by an individual actuator. In addition, it can be manufactured at low cost. As a result, the manufacturing cost of the gate valve 10 can be reduced and the space occupied by the gate valve 10 can be effectively reduced.

Moreover, it is only necessary to drive and control a single cylinder 62, the signal system is unified, which is economical, and a relay or the like is not required, so that reliability can be improved. There is an advantage.

Further, since the pipe member 38 is held in contact with the closing member 44 at the closed position P1 and the open position P2,
The shaft member 24 reliably advances and retracts in the pipe member 38 through the cam structure 84, so that the expansion and contraction operation of the gate portion 18 can be easily and reliably performed. At that time, since the spring member 54 is interposed between the shaft member 24 and the pipe member 38, the swinging movement and the forward / backward movement of the shaft member 24 are smoothly performed by the forward / backward action of the operating member 74 with a simple structure. It becomes feasible.

Furthermore, both side portions 76 of the operating member 74 are supported via the linear guides 78, so that the linear guides 78 can reliably receive the load acting on the operating member 74 in the vertical and horizontal directions. it can. Therefore, the forward / backward movement of the operating member 74 is surely performed, and the gate valve 10 can be accurately driven and controlled.

FIG. 6 is a sectional front view of the gate valve 100 according to the second embodiment of the present invention. The same components as those of the gate valve 10 according to the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In the pipe member 102 constituting the gate valve 100, the shaft member 24 is inserted such that it can move forward and backward, and
A step portion 104 is provided inside thereof. A spring seat 106 is provided at the upper end of the pipe member 102 so as to project inward, and the spring seat 106 and the spring seat 108 provided on the shaft member 24.
The spring member 110 is interposed between and.

Cam structure 1 constituting the gate valve 100
Reference numeral 12 is vertically opposite to the cam structure 84 constituting the gate valve 10 according to the first embodiment, and the arcuate swing surface 114 is at the lower end position, and the swing surface 11
The first and second inclined surfaces 116a and 116b which are inclined vertically upward by a predetermined angle toward the horizontal direction are provided on both sides of 4.

As shown in FIG. 7, the pressing mechanism 118 constituting the gate valve 100 is provided with a taper portion 119 provided on the opposite surface sides of both valve plates 22, and this taper portion 119 is in the direction of arrow A1. Slopes outward toward. When the shaft member 24 moves in the direction of the arrow A2, the rolling element 50 comes into contact with the tapered portion 119, and the pair of valve plates 22
Are configured to be displaceable in a direction in which they are separated from each other.

In the second embodiment thus constructed, the roller 58 is provided with the spring seat 10 provided on the shaft member 24.
8 and a spring seat 106 provided at the upper end of the pipe member 102 are constantly urged in the direction of arrow A1 through the elastic force of a spring member 110 interposed between them.

Therefore, the roller 58 can be held in sliding contact with the oscillating surface 114. In this state, when the operating member 74 is moved back and forth in the direction of arrow B under the driving action of the cylinder 62, the roller 58 is moved. Is pressed and supported by the swing surface 114, so that the shaft member 24 and the pipe member 102 can smoothly swing about the support shaft 20 between the closed position P1 and the open position P2.

Further, when the operating member 74 further moves in the direction of arrow B1 after the pipe member 102 abuts on the closing member 44 and is supported at the closed position P1, the roller 58 causes the roller 58 to move.
While compressing 10, the swing surface 114 to the first inclined surface 116
It moves relatively obliquely upward along a and moves the shaft member 24 in the direction of arrow A1.

As a result, the rolling element 50 provided on the shaft member 24 engages with the tapered portion 119, and the gate portion 18
The inside of the through hole is expanded, and the through holes 14a and 14b are reliably sealed. On the other hand, when the operating member 74 is moved in the direction of the arrow B2, the roller 58 moves to the swing surface 114 side along the first inclined surface 116a, so that the inside of the gate portion 18 is reduced and the valve box 16 is sealed. Is released.

When the operating member 74 further moves in the direction of the arrow B2, the roller 58 is supported by the swing surface 114, the gate portion 18 swings from the closed position P1 to the open position P2, and the pipe member 102 moves. The closing member 44 is abutted and supported. Further, the operating member 74 moves in the direction of the arrow B2, the roller 58 moves relatively obliquely upward along the second inclined surface 116b, and the expanding operation of the gate portion 18 is performed.

As a result, in the second embodiment, the inside of the gate portion 18 is expanded at the closed position P1 and the open position P2, and the sealing material 26 provided on the gate portion 18 has the first and second seals. It adheres to the surfaces 28a and 28b. Therefore, by-products do not adhere to the outer periphery of the sealing material 26, and the gate valve 1 is clean with a simple structure.
It is possible to obtain the same effect as that of the first embodiment.

FIG. 8 is a cross-sectional explanatory view of a gate portion 120 which constitutes a gate valve according to a third embodiment of the present invention, and FIG. 9 is a side view of the gate portion 120. The gate valve 1 according to the first and second embodiments
The same components as those of 0 and 100 are designated by the same reference numerals, and detailed description thereof will be omitted.

A pair of valve plates 12 constituting the gate section 120
The screw holes 124a and 124b are formed in the shaft 2 so as to face each other and coaxially in different directions. The pressing mechanism 126 for expanding and contracting the inside of the valve plate 122 includes a frame body 128 connected to the end of the shaft member 24, and the rack 130 extends in the direction of arrow A on the inner surface side of the frame body 128. Is provided.

A pinion 132 meshes with the rack 130, and screw shafts 134a, 13 are formed at the axial center position of the pinion 132 in which screws in different right and left directions are engraved.
4b is pivotally mounted, and the screw shafts 134a and 134b are screwed into the screw holes 124a and 124b.

In the third embodiment thus constructed, when the shaft member 24 advances and retreats in the direction of the arrow A, the rack 130 is inserted through the frame 128 fixed to the shaft member 24.
Moves back and forth in the direction of arrow A. 1 pinion on the rack 130
32 are meshed with each other, and the rack 130 moves back and forth in the direction of the arrow A, so that the pinion 132 moves the screw shaft 1
It rotates in a predetermined direction integrally with 34a and 134b. Therefore, the screw shafts 134a and 134b are attached to the screw holes 124.
The valve plates 122 are integrally rotated in a direction in which they are close to each other and a direction in which they are separated from each other.

As a result, in the third embodiment, the work of expanding and contracting the gate portion 120 can be reliably performed with a simple structure.
The same effect as that of the first and second embodiments can be obtained.

[0065]

In the gate valve according to the present invention, when the seal portion provided on the gate portion is placed at the closed position and the open position under the action of the actuating mechanism, the seal portion has the first position at the closed position. It is in close contact with the sealing surface and the second sealing surface in the open position. Therefore, in the open position, the seal portion is not exposed to the gas flowing through the through hole, and the by-product contained in the gas does not adhere to the surface of the seal portion.
As a result, it is possible to reliably prevent gas leakage due to by-products, and it is possible to reliably provide a clean gate valve with a simple and compact structure.

[Brief description of drawings]

FIG. 1 is a sectional front view of a gate valve according to a first embodiment of the present invention.

FIG. 2 is a sectional side view of the gate valve.

FIG. 3 is an explanatory view of a state in which a gate portion which constitutes the gate valve is arranged at an open position.

FIG. 4 is an operation explanatory diagram when the shaft member advances and retracts by the operation mechanism that constitutes the gate valve.

FIG. 5 is an operation explanatory diagram when the gate portion is expanded.

FIG. 6 is a sectional front view of a gate valve according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view of a pressing mechanism that constitutes the gate valve.

FIG. 8 is a cross-sectional explanatory view of a gate portion which constitutes a gate valve according to a third embodiment of the present invention.

FIG. 9 is a side view of the gate unit.

FIG. 10 is a schematic configuration explanatory diagram of a gate valve according to a conventional technique.

[Explanation of symbols]

10, 100 ... Gate valve 12a, 12b ... Side wall part 14a, 14b ... Through hole 16 ... Valve box 18, 120 ... Gate part 20 ... Support shaft 22, 122 ... Valve plate 24 ... Shaft member 26 ... Seal material 28a, 28b ... Sealing surfaces 30, 118 ... Pressing mechanism 32 ... Actuating mechanism 36 ... Base portion 38, 102 ... Pipe member 40 ... Rings 42, 46 ... Bellows member 44 ... Closing member 48, 119 ... Tapered portion 50 ... Rollers 54, 110 ... Spring member 58 ... Roller 62 ... Cylinder 64 ... Piston rod 74 ... Actuating member 76 ... Both sides 78 ... Linear guides 84, 112 ... Cam structure 90 ... Oscillation grooves 92a, 92b ... Seal grooves 94, 114 ... Oscillation surface 96a , 96b, 116a, 116b ... Inclined surface 124a, 124b ... Screw hole 128 ... Frame 130 ... Rack 132 ... Pinion 134a, 134b ... Screw

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F16K 31/54 F16K 31/54 41/10 41/10 51/02 51/02 B (72) Inventor Miyazaki Shogo 4-2-2 Kinnodai, Taniwahara-mura, Tsukuba-gun, Ibaraki SMC Tsukuba Technology Center (72) Inventor Mitsuhiro Someya 4-4-2-2 Kinnodai, Yawahara-mura, Tsukuba-gun, Ibaraki SMC F Co., Ltd. Tsukuba Technology Center (Reference) 3H053 AA02 BA11 BA24 DA09 3H056 AA05 BB22 CA01 CB02 CD04 DD08 GG14 3H063 AA04 BB22 DA15 DB01 DB11 DB32 GG15 3H066 AA03 BA19 DA11

Claims (5)

[Claims] 1. A closed position corresponding to a through hole provided in a side portion of the valve box with a gate portion disposed in the valve box as a center, and an open position separated from the through hole. Rock it to
A gate valve capable of opening and closing the through hole, wherein by displacing the gate portion to the side portion side of the valve box at the closed position and the open position, a sealing portion provided in the gate portion is provided. A first sealing surface provided at the closed position surrounding the through hole and a second sealing surface provided at the open position.
A pressing mechanism that can be in close contact with the sealing surface, and swings the gate portion around the support shaft,
An actuation mechanism for urging the pressing mechanism to displace the gate portion at the closed position and the open position. 2. The gate valve according to claim 1, wherein the pressing mechanism has an axis line that passes through the axis of the support shaft and intersects the axis, and moves forward and backward in the axial direction to displace the gate portion. The operating mechanism includes a single actuator, an operating member that engages with the actuator and is movable back and forth, swings the shaft member between the open position and the closed position, and closes the closed position. And a cam structure for advancing and retracting the shaft member in the axial direction at the position and the open position. 3. The gate valve according to claim 1 or 2, wherein the shaft member is inserted so as to be capable of advancing and retracting, and is swingable about the support shaft; and the gate portion that abuts on the pipe member. A closing member that holds the valve member in the closed position and the open position; and a bellows member that surrounds the pipe member, is fixed to the gate portion and the valve box, and is capable of sealing the inside of the valve box in an airtight manner. A gate valve characterized in that. 4. The gate valve according to claim 2, wherein the cam structure includes a roller provided on the shaft member, a swing groove provided on the actuating member, into which the roller is inserted, and the swing groove. A first seal groove and a second seal groove, which are provided in the operating member and communicate with both sides of the roller, and into which the roller is inserted; and when the operating member advances and retracts, the roller is arranged in the swing groove. While swinging the shaft member, the roller is moved to the first position at the closed position and the open position.
And a gate valve, wherein the seal portion of the gate portion is brought into close contact with the first and second seal surfaces by moving along the second seal groove. 5. The gate valve according to any one of claims 1 to 4, wherein both sides of the actuating member receive a load acting in a vertical direction and a lateral direction, so that the actuating member can move forward and backward. A gate valve, characterized in that a pair of linear guides are provided so as to extend in the interior of the gate valve.