JP2020122528A - Magnetic seal type gate valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic seal type gate valve capable of reducing the weight of a valve plate and simplifying an opening / closing mechanism. SOLUTION: A magnetically sealed gate valve 1 of the present invention has a valve box 3 provided with an opening 8, a valve plate 4 housed in the valve box 3 and opening and closing the opening 8, and the inside of the valve box 3. A valve rod 5 that supports the valve plate 4 so as to be able to move up and down, an elevating mechanism 6 that moves the valve rod 5 up and down by a predetermined stroke, and a permanent magnetized magnetic pole in the opening 8 direction provided on the sealing surface of the valve plate 4. A valve plate magnet portion 12 made of a magnet, a valve box magnet portion 20 made of a permanent magnet provided on the valve seat surface of the valve box 3 and magnetized with magnetic poles of the same type and different types as those of the valve plate magnet portion 12, and a valve. By switching the magnetic poles of the box magnet portion 20, the same type of magnetic poles repel the valve plate magnet portion 12 when the valve is opened, the valve plate 4 is separated from the valve seat surface, and different magnetic poles cause the valve plate magnet portion 12 when the valve is closed. It is configured to include an opening / closing mechanism 7 that sucks and brings the valve plate 4 into close contact with the valve seat surface. [Selection diagram] Fig. 3

Description

The present invention relates to a magnetic seal type gate valve that opens and closes an opening of a valve box by a magnet attractive force and a repulsive force.

The conventional general gate valve is a method of closing the opening of the valve box by raising and lowering and closely moving a valve plate having a sealing material, or by sandwiching an air cylinder between two valve plates facing each other and closing the valve. A method of directly sealing the opening of the valve box by applying air to the valve plate is adopted (for example, refer to Patent Document 1 for the former method and Patent Document 2 for the latter method).

JP, 9-324863, A JP, 2013-124773, A

Regarding the former type of gate valve, since the valve plate sealing force is determined by lever action, the mechanism part becomes large and complicated depending on the size of the opening of the valve box, and it is not competitive in terms of weight and cost. There's a problem. The latter type gate valve is particularly effective for large openings, but has a problem that the valve plate structure is complicated and it is difficult to develop products for small gate valves including those for semiconductors.

Therefore, the present invention has been made to solve such a problem, and an object thereof is to provide a magnetic seal type gate valve capable of reducing the weight of a valve plate and simplifying an opening/closing mechanism. To do.

In order to achieve the above-mentioned object, a magnetic seal type gate valve of the present invention includes a valve box having an opening, a valve plate housed in the valve box to open and close the opening, and a valve box. A valve rod that supports the valve plate so that the valve plate can be moved up and down, an elevating mechanism that moves the valve rod up and down for a predetermined stroke, and A valve plate magnet portion, a valve box magnet portion provided on the valve seat surface of the valve box, and comprising a permanent magnet magnetized with magnetic poles of the same type and different types as the magnetic poles of the valve plate magnet portion, and the valve box magnet portion. By switching the magnetic poles, the same kind of magnetic pole repels the valve plate magnet portion when the valve is opened, the valve plate separates from the valve seat surface, and different types of magnetic poles attract the valve plate magnet portion when the valve is closed. An opening/closing mechanism in which the valve plate is in close contact with the valve seat surface.

Further, in the magnetic seal type gate valve of the present invention, the opening/closing mechanism is configured such that a valve box magnet portion formed of a columnar magnet in which magnetic poles of the same type and different types as the magnetic poles of the valve plate magnet portion are magnetized on half surfaces is provided around the axis. It may be a rotation mechanism that makes half rotation.

Further, in the magnetic seal type gate valve of the present invention, in the opening/closing mechanism, the valve box magnet portions made of the pillar-shaped magnets are arranged above and below the opening, and when the valve is opened, the upper and lower pillar-shaped magnets are formed. The magnets may be rotated outward half a turn, and the upper and lower columnar magnets may be rotated inward half a turn when the valve is closed.

Further, in the magnetic seal type gate valve of the present invention, the opening/closing mechanism may be configured by a combination of a plurality of divided magnet bodies in a valve box magnet portion formed of the pillar-shaped magnet.

Further, in the magnetic seal type gate valve of the present invention, the opening/closing mechanism includes a valve plate auxiliary magnet portion formed of a permanent magnet having a magnetic pole magnetized on a surface opposite to the sealing surface of the valve plate, and the valve box described above. You may further provide the valve box auxiliary magnet part which consists of a permanent magnet which magnetized the same kind of magnetic pole in the surface which opposes a valve plate auxiliary magnet part.

Further, in the magnetic seal type gate valve of the present invention, the valve plate magnet portion and the valve box magnet portion are respectively provided for the first opening and the second opening provided on both side surfaces of the valve box. The valve plate may selectively open and close the first opening and the second opening by the opening/closing mechanism.

As is apparent from the above configuration, according to the magnetic seal type gate valve of the present invention, by utilizing the attraction force and repulsion force of the magnet as the valve plate sealing force, the conventional cam or valve plate internal cylinder method is used. The sealing mechanism can be eliminated, and the valve plate can be reduced in weight and the opening/closing mechanism can be simplified.

It is an enlarged view of the valve main body in the magnetic seal type gate valve of this invention, (A) is a perspective view which shows the external appearance of a valve main body, (B) is a perspective view which shows the internal structure except the valve box of a valve main body. .. It is a top view showing the whole magnetic seal type gate valve structure of the present invention. It is a longitudinal section showing an internal structure of a magnetic seal type gate valve of the present invention. It is a detailed view of the valve main body in the magnetic seal type gate valve of the present invention, (A) is a left side view of the valve main body, (B) is a vertical cross-sectional view of the valve main body, (C) is a C-C cross-sectional view, D) is a vertical sectional view of the valve plate portion. FIG. 4 is an operation explanatory view of the magnetic seal type gate valve of the present invention, (A) is a longitudinal sectional view showing a state when the valve is closed, (B) is the valve plate fully opened, (C) is the rising end stop of the valve plate And (D) is a vertical cross-sectional view of the valve body showing a state when the valve plate is sealed. FIG. 6 is an operation explanatory view of the magnetic seal type gate valve of the present invention, (A) is a longitudinal sectional view showing a state when the valve is open, (B) is a valve plate fully closed, and (C) is a valve plate seal open. (D) is a vertical cross-sectional view of the valve body showing a state when the lower end of the valve plate is stopped. It is a figure which shows the modification of the magnetic seal type|mold gate valve of this invention, (A) is a longitudinal cross-sectional view of a valve main body, (B) is a longitudinal cross-sectional view of a valve plate part.

Hereinafter, modes for carrying out the present invention will be described with reference to the drawings.

As shown in FIG. 1, a magnetically sealed gate valve 1 according to the present embodiment is used for separating a vacuum from a vacuum or an atmosphere from a vacuum in an apparatus for manufacturing a flat panel display or a semiconductor substrate. It is used for the purpose of isolating various processes in manufacturing. As shown in FIGS. 1 to 4, a valve body 2 of the magnetic seal type gate valve 1 is a so-called valve box type valve, and is a flat rectangular valve box 3 and is housed inside the valve box 3. Valve plate 4, a valve rod 5 connected to the valve plate 4, an elevating mechanism 6 for elevating and lowering the valve rod 5 by a predetermined stroke, and an opening/closing mechanism 7 that uses the attractive force and repulsive force of a magnet as a valve plate sealing force. It is configured with.

Elongated openings (first opening 8 and second opening 9) are provided on the left and right side surfaces of the valve box 3 to allow the substrate to pass therethrough. A process chamber (not shown) is connected to the outer wall surface of the first opening 8, and a transfer chamber (not shown) is connected to the outer wall surface of the second opening 9. The substrate transferred from the transfer chamber to the process chamber through the valve box 3 is placed in a sealed environment by closing the first opening 8 with the valve plate 4, and the substrate is placed inside the process chamber. Processing such as heat, gas, and plasma for various film formations is performed.

As shown in FIG. 4, in the indoor space 10 of the valve box 3, one valve plate 4 for opening and closing the first opening 8 is arranged between the wall surfaces of the two openings 8 and 9. .. An O-ring 11 is fitted and fixed to the outer side surface of the valve plate 4 as an elastic seal member having a size slightly larger than the first opening 8. Further, on the sealing surface of the valve plate 4, a valve plate magnet portion 12 having a flat permanent magnet embedded in the vertical direction of the O-ring 11 is provided along the horizontal direction. The valve plate magnet portion 12 has a magnetic pole magnetized in the opening direction, and in this embodiment, the S pole is magnetized on the first opening 8 side as shown in FIG. 4B. The surface of the valve plate 4 opposite to the sealing surface is a valve plate auxiliary magnet portion 13 made of a permanent magnet, and the N pole is magnetized on the second opening 9 side.

A valve rod 5 that detachably supports the valve plate 4 is detachably attached to the center of the valve plate 4. The valve plate 4 removed from the valve rod 5 is taken out to the outside by removing the maintenance flange 14 that closes the top surface of the valve box 3 and opening the lid, for cleaning the surface and replacing the O-ring 11. Maintenance work can be performed.

As shown in FIGS. 2 and 3, the valve rod 5 extends through the center of the bonnet flange 15 that closes the bottom surface of the valve box 3 and extends to the outside of the valve box 3. A rod guide 16 that supports the valve rod 5 and guides its movement is provided at an intermediate position of the valve rod 5. Between the rod guide 16 and the bonnet flange 15, a stretchable metal bellows 17 such as a welded bellows or a molded bellows is attached so as to cover the periphery of the valve rod 5, so that the valve rod 5 is completely protected from the outside. It has been cut off. Further, as a lifting mechanism 6 for the valve plate 4, a piston rod 19 of a lifting air cylinder 18 is connected to the lower end of the valve rod 5.

On the valve seat surface of the valve box 3 facing the valve plate magnet section 12, there is provided a valve box magnet section 20 made of permanent magnets arranged in the horizontal direction above and below the first opening 8. .. In the present embodiment, the valve box magnet portion 20 has magnetic poles (S poles) of the same type as the magnetic poles (S poles) of the valve plate magnet portion 12 and different magnetic poles (N poles) attached to each half surface, as shown in FIG. 4B. An opening/closing mechanism 7 is provided which is composed of a magnetized cylindrical magnet and has a rack and pinion mechanism at both ends thereof.

The opening/closing mechanism 7 constitutes a rotating mechanism by meshing a gear-shaped pinion gear 21 attached to both ends of a cylindrical magnet with a linear rack 24 connected to a piston rod 23 of a sealing air cylinder 22. ing. In this rotating mechanism, the linear motion of the rack 24, which moves up and down by the driving of the sealing air cylinder 22, is converted into the rotating motion by the pinion gear 21, and the valve box magnet portion 20 formed of a cylindrical magnet is driven by the motor 25 by the ball bearing. The structure is rotatably supported around the axis via 26. By rotating the valve box magnet section 20 by half with this rotating mechanism, the magnetic pole of the valve box magnet section 20 facing the valve plate magnet section 12 can be switched to either the S pole or the N pole. There is. In the present embodiment, the rack-and-pinion mechanism and the sealing air cylinders 22 that form the opening/closing mechanism 7 are installed on both the left and right sides of the valve box 3 so that the upper and lower valve box magnets 20A and 20B rotate in opposite directions. Is configured.

Further, as a mechanism for assisting the opening/closing mechanism 7, the side surface on the opposite side of the valve box 3 facing the valve plate auxiliary magnet portion 13 is arranged in a horizontal direction above and below the second opening 9. A valve box auxiliary magnet portion 27 made of a magnet is provided. In this embodiment, the valve box auxiliary magnet portion 27 has a magnetic pole (N pole) of the same kind as the magnetic pole (N pole) of the valve plate auxiliary magnet portion 13 and a different kind of magnetic pole (S pole) as shown in FIG. 4B. Each of them is composed of a cylindrical magnet magnetized, and the same kind of magnetic pole (N pole) is embedded and fixed in the wall surface of the valve box 3 so as to face the valve plate auxiliary magnet portion 13.

The above is the structure of the magnetic seal type gate valve 1 of the present embodiment, and its operation will be described below. FIG. 5 shows the CLOSE operation from the fully opened state to the fully closed state of the valve body 2, and FIG. 6 shows the OPEN operation from the fully closed state to the fully opened state of the valve body 2.

When the valve rod 5 is lowered and the rod guide 16 is at the lowermost end as shown in FIG. 6(A), the magnetic pole (S pole) of the valve plate magnet portion 12 and the valve box magnet portion 20 as shown in FIG. 5(B). Of the valve plate auxiliary magnet portion 12 and the magnetic pole (N pole) of the valve box auxiliary magnet portion 27 repel each other, so that the valve plate 4 inside the valve box 3 is repulsed. It is kept in the neutral position and is in a fully opened state, which is located below the first opening 8. In this fully opened state, the substrate can be passed from the second opening 9 (transfer chamber side) to the first opening 8 (process chamber side).

Here, to bring the process chamber side into the closed state, first, compressed air is supplied to the lifting air cylinder 18 to drive the lifting air cylinder 18. As a result, the valve rod 5 connected to the piston rod 19 rises by a predetermined stroke, and as shown in FIG. 5C, the valve plate 4 is kept at the neutral position and the height position corresponding to the first opening 8 is increased. Move to the rising end and stop.

After the rising end is stopped, compressed air is supplied to the sealing air cylinder 22 to drive the sealing air cylinder 22, and the valve closing operation by the opening/closing mechanism 7 is performed. When the rack 24 connected to the piston rod 23 moves up by a predetermined stroke by driving the sealing air cylinder 22, the pinion gear 21 rotates, and the motor 25 drives the valve box magnet portion 20 to make a half rotation about the axis. As shown in (D), the magnetic pole of the valve box magnet portion 20 is switched from the S pole to the N pole. As a result, the magnetic pole (N pole) of the valve box magnet section 20 attracts the magnetic pole (S pole) of the valve plate magnet section 12 by magnetic force, and the sealing surface of the valve plate 4 comes into close contact with the valve seat surface of the valve box 3. The sealing of the first opening 8 is completed.

At this time, the cylindrical valve box magnets 20 arranged above and below the first opening 8 are both directed inward (the upper valve box magnet 20A is turned counterclockwise, and the lower valve box magnet 20B is turned clockwise). When the valve box magnet portion 20 is rotated by a half rotation, the attractive force of the valve box magnet portion 20 is generated in the horizontal direction indicated by the straight line arrow. Further, since the magnetic pole (N pole) of the valve plate auxiliary magnet portion 13 and the magnetic pole (N pole) of the valve box auxiliary magnet portion 27 repel each other, the non-sealing repulsive force acts on the valve plate 4 in an auxiliary manner. Therefore, the valve plate 4 can be uniformly attached to the valve seat surface without tilting. This is the CLOSE operation from the fully open state to the fully closed state.

On the other hand, in order to open the process chamber side, the supply of compressed air to the sealing air cylinder 22 is stopped in the state shown in FIG. 6(B). Then, the rack 24 connected to the piston rod 23 descends by a predetermined stroke, the pinion gear 21 rotates in the reverse direction, and the motor 25 drives the valve box magnet portion 20 to rotate halfway around the axis, as shown in FIG. 6C. Then, the magnetic pole of the valve box magnet section 20 is switched from the N pole to the S pole. As a result, the magnetic pole (S pole) of the valve box magnet section 20 repels the magnetic pole (S pole) of the valve plate magnet section 12 by magnetic force, the valve plate 4 is separated from the valve seat surface of the valve box 3, and the seal is opened. It

At this time, both of the cylindrical valve box magnets 20 arranged above and below the first opening 8 face outward (the upper valve box magnet 20A is rotated clockwise and the lower valve box magnet 20B is rotated counterclockwise). When the valve box magnet portion 20 is rotated by a half turn, the repulsive force of the valve box magnet portion 20 is generated in the horizontal direction indicated by the straight line arrow. Further, since the magnetic pole (N pole) of the valve plate auxiliary magnet portion 13 and the magnetic pole (N pole) of the valve box auxiliary magnet portion 27 repel each other, the repulsive force is also applied to the valve plate 4 from the second opening 9 side. Works. Therefore, these repulsive forces have the effect of reducing the impact of the valve plate 4 when the seal is opened.

Finally, the supply of compressed air to the lifting air cylinder 18 is stopped. As a result, the valve rod 5 connected to the piston rod 19 is lowered by a predetermined stroke, and the valve plate 4 is lowered below the first opening 8 while maintaining the neutral position as shown in FIG. 6D. Move to the end and stop. This is the OPEN operation from fully closed to fully open.

As described above, in the magnetic seal type gate valve 1 of the present embodiment, by switching the magnetic poles of the valve box magnet portion 20, the attraction force and repulsive force of the magnet are used to open/close the valve plate 4. The opening/closing mechanism 7 is adopted. Therefore, it is possible to eliminate the seal mechanism that has been conventionally performed by the cam or the valve plate internal cylinder method, and it is possible to reduce the weight of the valve plate 4 and simplify the opening/closing mechanism 7. Further, permanent magnets are used for the valve plate magnet section 12 and the valve box magnet section 20, and a rotation mechanism based on a rack and pinion mechanism is adopted, and the valve box magnet section is driven by the sealing air cylinder 22 and the motor 25 via the pinion gear 21. By driving 20, the special control and cooling like the electromagnet are not required, so that the magnetic seal type opening/closing mechanism 7 can be realized easily and at low cost.

Although the valve box magnet portion 20 is a columnar permanent magnet in the above-described embodiment, the shape thereof is not limited to the columnar shape, and may be another columnar shape such as a square pole. Further, a flat plate-shaped permanent magnet is used for the valve plate magnet portion 12 and a cylindrical permanent magnet is used for the valve box magnet portion 20, but instead of this, as shown in FIG. The divided magnet bodies 28, 28,... May be combined, and the valve box magnet part 20 may be formed by a combination of a plurality of short divided magnet bodies 29, 29,. With such a structure, for example, by optimizing the magnetizing direction and arrangement of the divided magnet bodies 29 that form the valve box magnet section 20, it is possible to increase the magnetic force in a specific direction, and the sealing force of the valve plate 4 is increased. It can be expected to have the effect of increasing the pressure and the effect of reducing the repulsive force when the seal is opened.

Further, the valve plate auxiliary magnet portion 13 and the valve box auxiliary magnet portion 27 are eliminated, and the valve plate magnet portion is provided with respect to the first opening 8 and the second opening 9 provided on both side surfaces of the valve box 3, respectively. A configuration may be adopted in which the valve box magnet portion 20 that rotates with 12 is provided. As a result, the valve plate 4 is configured to selectively open and close the first opening 8 and the second opening 9, and the valve plate is kept airtight in the chamber with one of the openings closed. It is possible to take out 4 to the outside and perform maintenance work such as cleaning and replacement of the O-ring 11.

1: Magnetic seal type gate valve 2: Valve body 3: Valve box 4: Valve plate 5: Valve rod 6: Lifting mechanism 7: Opening/closing mechanism 8: First opening 9: Second opening 10: Indoor space 11 : O-ring 12: Valve plate magnet part 13: Valve plate auxiliary magnet part 14: Maintenance flange 15: Bonnet flange 16: Rod guide 17: Bellows 18: Lifting air cylinder 19: Piston rod 20: Valve box magnet part 21: Pinion Gear 22: Sealing air cylinder 23: Piston rod 24: Rack 25: Motor 26: Ball bearing 27: Valve box auxiliary magnet 28: Split magnet (valve plate magnet)
29: Split magnet body (valve box magnet part)

Claims (6)

A valve box with an opening,
A valve plate that is housed in the valve box and that opens and closes the opening,
A valve rod that supports the valve plate in the valve box so that the valve plate can move up and down;
An elevating mechanism for elevating the valve rod by a predetermined stroke,
A valve plate magnet portion which is provided on the sealing surface of the valve plate and is made of a permanent magnet having a magnetic pole magnetized in the opening direction;
A valve box magnet portion which is provided on the valve seat surface of the valve box, and which is composed of a permanent magnet magnetized with magnetic poles of the same type and different types as the magnetic poles of the valve plate magnet portion;
By switching the magnetic poles of the valve box magnet section, the same kind of magnetic pole repels the valve plate magnet section when the valve is opened, the valve plate separates from the valve seat surface, and different kinds of magnetic poles are the valve plate magnet when the valve is closed. An opening/closing mechanism for sucking a portion of the valve plate so that the valve plate comes into close contact with the valve seat surface. 2. The opening/closing mechanism is a rotating mechanism for rotating a valve box magnet portion, which is a columnar magnet in which magnetic poles of the same type and different types as the magnetic poles of the valve plate magnet portion are magnetized half-face by half, about an axis. Magnetic seal type gate valve described in. In the opening/closing mechanism, the valve box magnets composed of the pillar-shaped magnets are arranged above and below the opening, and when the valve is opened, the upper and lower pillar-shaped magnets are rotated outward by half a turn to close the valve. The magnetically sealed gate valve according to claim 2, wherein sometimes the upper and lower columnar magnets are rotated inward by half a turn. The magnetic seal type gate valve according to claim 2, wherein the opening/closing mechanism is configured by combining a plurality of divided magnet bodies with a valve box magnet portion formed of the pillar-shaped magnet. The opening/closing mechanism includes a valve plate auxiliary magnet portion formed of a permanent magnet having a magnetic pole magnetized on a surface opposite to the sealing surface of the valve plate, and a valve plate auxiliary magnet portion of the valve box facing the valve plate auxiliary magnet portion of the same kind. The magnetic seal type gate valve according to any one of claims 1 to 4, further comprising a valve box auxiliary magnet portion formed of a permanent magnet having a magnetic pole magnetized. The valve plate magnet portion and the valve box magnet portion are respectively provided for the first opening portion and the second opening portion provided on both side surfaces of the valve box, and the valve plate is opened by the opening/closing mechanism. The magnetic seal type gate valve according to any one of claims 1 to 4, which is configured to selectively open and close the first opening and the second opening.