JP4099766B2 - Easy maintenance gate valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gate valve that is disposed in a passage for transferring a workpiece between vacuum chambers of a semiconductor manufacturing apparatus or the like and that facilitates maintenance of a bellows assembly.
[0002]
[Prior art]
As shown in FIG. 5, the conventional gate valve described in Patent Document 1 below has a shaft 124 with a main valve element fixed to the upper end portion thereof through the insertion hole 144 of the first base plate 136. The lower end of the shaft 124 is fixed to the lever member 180. The small diameter portion 101 at the lower end of the shaft 124 is inserted into the hole portion 100 of the lever member 180, and the lock nut 102 is screwed into the small diameter portion 101. In order to maintain the inside of the valve body and the inside of the insertion hole 144 in a vacuum state, a bellows assembly composed of an upper ring body 152, a bellows 150, and a lower ring body 104 is provided. The upper ring body 152 is held in the hole of the second base plate 138, and the lower ring body 104 is sandwiched between the stepped portion of the shaft 124 and the lever member 180.
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-356186
When a conventional gate valve is applied to a semiconductor manufacturing apparatus and the apparatus is operated, the wafer is damaged by some force, and a piece of wafer breaks between the insertion hole 144 of the first base plate 136 and the shaft 124. May fall into the bellows 150 through the gap. A wiper (not shown) is mounted between the insertion hole 144 and the shaft 124, but fine debris of the wafer enters through a slight gap. If the semiconductor manufacturing equipment is operated while the fine wafer debris has fallen into the bellows 150, the bellows 150 is destroyed by the fine wafer debris, and the atmosphere in the bellows 150 and the valve body (vacuum chamber). Will flow in.
[0004]
If it is found that wafer fragments have fallen into the bellows 150, the operation of the semiconductor manufacturing apparatus must be immediately stopped and the bellows assembly must be replaced. However, in order to remove the bellows assembly from the conventional gate valve, it is necessary to remove the shaft 124, the first base plate 136, and the second base plate 138, and the gate valve must be disassembled by 50% or more. Moreover, disassembling the gate valve, replacing the bellows assembly, and assembling the gate valve require a special jig, and adjustment of the angle between the shaft 124 and the lever member 180 requires skill. It was impossible to replace the bellows assembly at the site where it was used.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to make it possible to easily replace a bellows assembly of a gate valve in a short time even at a site where the gate valve is used.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is configured such that the shaft is inserted into the insertion hole of the operation body, the lower end portion of the shaft is connected to the lever member, and the inner surface of the insertion hole and the outer surface of the shaft in the operation body are provided. In the gate valve in which the bellows assembly is disposed, the air cylinder is disposed in the operation body, the shaft is connected to the piston rod of the air cylinder, and the shaft moves up and down and swings.
The bellows latch of the bellows assembly is fitted to the operation body, the set screw is screwed into the screw hole of the upper end protruding part of the lever member, and the thrust of the set screw acts on the annular groove on the outer periphery of the bellows holder. A first easy-to-maintain gate valve is characterized in that the holder is connected to the lever member in an airtight state.
According to the present invention, in the first configuration, the inclined lower wall of the annular groove on the outer periphery of the bellows holder is inclined radially outward and downward, and the thrust of the set screw acts on the inclined lower wall, so that the bellows holder The lower surface is pressed against the annular surface of the lever member, the space between the lower surface of the bellows holder and the annular surface is sealed by an O-ring, and the space between the lever member and the shaft member is sealed by an O-ring. .
In the present invention, the shaft is inserted into the insertion hole of the operation body, the lower end of the shaft is connected to the lever member, and the bellows assembly is disposed between the inner surface of the insertion hole and the outer surface of the operation body of the shaft. In a gate valve in which an air cylinder is arranged in the body, a shaft is connected to a piston rod of the air cylinder, and the shaft moves up and down and swings.
The bellows latch of the bellows assembly is fitted to the operation body, the set screw is screwed into the screw hole of the upper end protruding part of the lever member, and the thrust of the set screw acts on the annular groove on the outer periphery of the bellows holder. A gate valve easy to maintain, characterized in that the holder is connected to the shaft in an airtight state, is a third configuration.
In the third configuration of the present invention, the inclined lower wall of the annular groove on the outer periphery of the bellows holder is inclined radially outward and downward, and the thrust of the set screw acts on the inclined lower wall, so that the bellows holder The fourth configuration is that the lower surface is pressed against the annular surface of the lever member, and the space between the bellows holder and the large-diameter portion of the shaft is sealed by an O-ring.
In the first configuration and the third configuration, the bellows assembly is such that the bellows locking tool and the bellows holder are respectively connected in an airtight state at the upper end and the lower end of the bellows, and the bellows locking tool is inserted into the insertion hole of the operation body. It is fitted in a sealed state, and the center line of the conical set screw can pass through a position away from the air cylinder by a predetermined distance in the front-rear direction.
In the first and third configurations, the set screw can be a conical set screw, and the conical portion of the conical set screw can be engaged with the annular groove on the outer periphery of the bellows holder.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
1 to 3 show Embodiment 1 of a gate valve with easy maintenance according to the present invention. As shown in FIGS. 1 to 3, two air cylinders 13 </ b> A are provided on the left and right upper portions in the operation body 10 and on the lower side of the first base plate 11 via two left and right second base plates 12 </ b> A and 12 </ b> B.・ 13B is fixed. Two piston rods 14A and 14B extend downward from the air cylinders 13A and 13B, and lower ends of the two piston rods 14A and 14B are connected to left and right ends of the cam support member 15, respectively. Two cam members 16A and 16B are fixed to the cam support member 15 at positions closer to the inside of the two piston rods 14A and 14B. Two cam members 16A and 16B are provided on both sides of the lower end of the lever member 18 in the cam groove. The rollers 19A and 19B are engaged with each other. A spring 20 is mounted between the lever member 18 and the cam support member 15, and the lever member 18 is urged upward by the spring 20.
[0008]
An insertion hole 21 is formed in the first base plate 11 at the upper end of the operation body 10, a shaft 22 is inserted through the insertion hole 21, and the shaft 22 extends above the operation body 10. The shaft 22 has a medium diameter portion 23, a large diameter portion 24, and a small diameter portion 25 from the upper end to the lower end, and a main valve element (not shown) is fixed to the upper end portion of the medium diameter portion 23. The small diameter portion 25 at the lower portion of the shaft 22 is inserted into the central hole 27 of the lever member 18, and the stepped portion between the large diameter portion 24 and the small diameter portion 25 of the shaft 22 is brought into contact with the annular surface 55 of the lever member 18. The nut 28 is screwed into the male thread portion at the lower end of the small diameter portion 25, and thus the shaft 22 and the lever member 18 are connected. An annular groove is formed at the upper end of the central hole 27, and an O-ring 29 for the shaft (see FIG. 2) is attached to the annular groove, and the shaft 22 and the lever member 18 are sealed by the O-ring 29. Two pivots 26A and 26B are fixed to both sides of the left and right upper end protrusions 51A and 51B of the lever member 18, and the two second base plates 12A and 12B are positioned right above the two pivots 26A and 26B. Two pivot receiving grooves 31A and 31B are disposed at each inner end.
[0009]
As shown in FIG. 3, the bellows assembly 32 used in the easy-maintenance gate valve of the present invention has the upper end of the bellows 34 connected to the lower end of the bellows locking member 33 in an airtight state by welding or the like. The lower end is connected to the upper end of the annular bellows holder 35 in an airtight state by welding or the like. The bellows locking member 33 has a generally cylindrical shape, an insertion hole 41 is formed on the inner side, and a support portion 40 is formed on the outer side at a position closer to the upper side than the center in the vertical direction. The support portion 40 has a substantially square shape with corners cut in a top view of FIG. 3 (a). Four support bolt insertion holes are formed therethrough, and the support portion 40 has a predetermined vertical width. A frustoconical portion and an annular step portion are formed from the upper end of the bellows locking tool 33 toward the support portion 40, and a cylindrical portion 49 is formed below the support portion 40. A countersunk machine screw 57 with a cross hole is inserted into the four bolt insertion holes of the support portion 40, and the machine screw 57 is screwed into the female screw of the first base plate 11. The first base plate 11 is fixed in a sealed state.
[0010]
The shape of the bellows holder 35 is a ring, an insertion hole 44 is formed on the inner surface, and an annular groove 45 for engagement is formed on the outer periphery. The upper wall 46 of the annular groove 45 is substantially parallel to the upper surface (perpendicular to the insertion hole 44), and the inclined lower wall 47 is inclined radially outward and downward. An annular groove is formed at a position closer to the inner side in the radial direction on the lower surface of the bellows holder 35, and an O-ring 48 for the bellows holder is attached to the annular groove.
[0011]
A large-diameter hole 36, a small-diameter hole 37, and a medium-diameter hole 38 are formed in the insertion hole 21 of the first plate 11 from the upper end to the lower end. The large-diameter hole 36 is a support portion 40 of the bellows locking tool 33. Is a hole with a shape and size suitable for fitting. The outer diameter of the bellows holder 35, the outer diameter of the bellows 34, and the diameter of the cylindrical portion 49 of the bellows locking tool 33 are smaller than the diameter of the small diameter hole 37 of the insertion hole 21 (the smallest diameter portion of the insertion hole 21). 35, the bellows 34, and the cylindrical portion 49 of the bellows locking member 33 can be inserted into the small-diameter hole 37 of the insertion hole 21. The minimum diameter of the outer periphery of the support portion 40 of the bellows locking tool 33 is larger than the diameter of the small diameter hole 37 of the insertion hole 21, and even if the bellows locking tool 33 is to be inserted into the insertion hole 21, the bellows locking tool 33 The lower surface of the support portion 40 cannot be inserted into contact with the step portion between the small diameter hole 37 and the large diameter hole 36 of the insertion hole 21.
[0012]
1 and 2 show a state in which the bellows assembly 32 is mounted in the operation body 10. As shown in FIGS. 1 (a) and 1 (b), the shape of the upper end protrusions 51A and 51B protruding left and right at the upper end of the lever member 18 is such that a predetermined portion on the front and rear sides of a cylinder having a predetermined thickness and a predetermined height is vertical. It is a deleted shape. A virtual YY straight line (perpendicular to the front side plate 61 and the rear side plate 62 of the operation body 10) passing through the center point 52 of the arcuate upper end protrusions 51A and 51B in the top view of FIG. Two virtual straight lines that pass through the center point 52 and form a predetermined angle (for example, about 60 degrees) with respect to the virtual YY straight line are assumed, and a screw hole 53 coaxial with the virtual straight line has an upper end protruding portion 51A. And two are formed in the lower part of 51B.
[0013]
A conical set screw 54 is screwed into each of the four screw holes 53, and a conical portion (a truncated conical portion) of the conical set screw 54 is engaged with the inclined lower wall 47 of the bellows holder 35. By this engagement, the bellows The lower surface of the holder 35 is pressed against the annular surface 55 of the lever member 18. The space between the bellows holder 35 and the annular surface 55 of the lever member 18 is sealed by an O-ring 48 in the annular groove of the bellows holder 35. As can be seen from FIG. 1 (b), the center line of the conical set screw 54 (same as the two virtual straight lines) passes through a place separated in the front-rear direction by a predetermined distance from the left and right air cylinders 13A and 13B. In other words, the wrench (hexagonal wrench) engaged with the operation hole (hexagonal socket) of the conical set screw 54 is separated by a predetermined distance in the front-rear direction (forward or backward) from the left and right air cylinders 13A and 13B. Go through the point. Accordingly, with the front side plate 61 and the rear side plate 62 removed, the tip of the hexagon wrench can be engaged with the hexagon hole of the conical set screw 54 to rotate the conical set screw 54.
[0014]
Next, an operation for replacing the bellows assembly 32 when fine fragments fall into the bellows assembly 32 due to wafer breakage will be described. FIG. 1A shows a state in which a valve body (not shown) connected to the upper side of the operation body 10 and a main valve body in the valve body are removed, and a front side plate 61 and a rear side plate 62 of the operation body 10 are removed. Has been. First, the machine screw 57 for connecting the bellows locking tool 33 to the first base plate 11 is rotated in the anti-screwing direction, and the machine screw 57 is removed from the bellows locking tool 33. The tip of the hexagon wrench is engaged with the hexagonal hole of the conical set screw 54, and the conical set screw 54 is rotated counterclockwise a predetermined number of times, and the conical portion of the conical set screw 54 and the inclined lower wall 47 of the bellows holder 35 are Release the engagement. Since there are four conical set screws 54, this release operation is repeated four times. At this time, as can be seen from FIG. 1 (b), since the hexagon wrench passes through the front position or the rear position by a predetermined distance from the air cylinders 13A and 13B, the shaft 22 and the lever member 18 are connected in this state. Release operation can be performed. In this state, when the bellows locking tool 33 is lifted directly above, the bellows 34 and the bellows holder 35 pass through the small diameter hole 37 (minimum diameter portion) of the insertion hole 21, and the bellows assembly 32 is removed from the operation body 10. It is.
[0015]
Prepare a new bellows assembly 32, attach an O-ring 48 to the annular groove on the lower surface of the bellows holder 35, and make sure that the outer surface of the bellows 34 does not contact the inner surface of the insertion hole 21. Insert through. The annular surface 55 of the lever member 18 and the O-ring 48 of the bellows holder 35 are brought into contact with each other without tilting, and the support portion 40 of the bellows locking tool 33 is fitted into the insertion hole 21. The small screw 57 is inserted into the bolt insertion hole of the bellows locking tool 33, and the small screw 57 is screwed into the female screw of the first base plate 11 to connect the bellows locking tool 33 to the first base plate 11. Next, the four conical set screws 54 screwed into the screw holes 53 of the upper end projecting portions 51A and 51B of the lever member 18 are tightened evenly so as not to apply a rotational force to the bellows holder 35. The bellows assembly 32 is fixed to the lever member 18 by engaging the conical portion of this with the inclined lower wall 47 of the bellows holder 35. The front side plate 61 and the rear side plate 62 are attached to the operation body 10, the main valve body is attached to the upper end portion of the shaft 22, and the valve body is connected to the upper side of the operation body 10. In this way, the bellows assembly 32 is exchanged.
[0016]
FIG. 4 shows a second embodiment of a gate valve with easy maintenance according to the present invention. The second embodiment is different from the first embodiment in the sealing means between the bellows holder 35 and the shaft 22. That is, as shown in FIG. 4, an annular groove 65 is formed at the upper end of the central hole 27 of the lever 18, and the length of the large diameter portion 24 of the shaft 22 is the same as the longitudinal length of the annular groove 65. Has been. An annular groove is formed at the radially inner end of the lower surface of the bellows holder 35, and an O-ring 59 for the bellows holder is attached to the annular groove of the bellows holder 35. The large-diameter portion 24 of the shaft 22 is fitted into the annular groove 65 of the lever 18, and the small-diameter portion 25 and the large-diameter portion 24 of the shaft 22 are connected to the step portion between the central hole 27 of the lever 18 and the annular groove 65. The step part between them is in contact. An O-ring 59 is in contact with a step portion between the large diameter portion 24 and the medium diameter portion 23 of the shaft 22, and the bellows holder 35 and the shaft 22 are sealed by the O ring 59. The other configuration of the second embodiment is the same as the configuration of the first embodiment, and the replacement operation of the bellows assembly of the second embodiment is the same as that of the first embodiment.
[0017]
【The invention's effect】
In the present invention, in a state where the shaft and the lever member are connected, the conical set screw is loosened to release the engagement between the conical portion of the conical set screw and the annular groove (inclined lower wall) of the outer periphery of the bellows holder, By lifting the bellows locking device directly above, the bellows assembly can be extracted from the insertion hole and removed from the operation body. Then, a new bellows assembly can be mounted in the operation body by an operation reverse to the removal of the bellows assembly. The bellows assembly is exchanged with the shaft and lever member connected, so there is no need for the difficult work of adjusting the angle between the shaft and lever member and fastening the shaft and nut. Since it is not necessary, the bellows assembly can be easily replaced at the site where the gate valve is used.
[Brief description of the drawings]
FIG. 1 (a) is an explanatory front view of an easy-maintenance gate valve according to Embodiment 1 of the present invention, and FIG. 1 (b) is a cross-sectional view taken along line AA in FIG. It is the partial cross section explanatory view seen in.
FIG. 2 is an enlarged view of a main part of FIG.
FIG. 3 (a) is a top view of a bellows assembly used in an easily maintainable gate valve according to an embodiment of the present invention, and FIG. 3 (b) is a side sectional view of FIG. 3 (a). is there.
FIG. 4 is an enlarged view of a main part of a front explanatory view of an easily maintainable gate valve according to a second embodiment of the present invention.
FIG. 5 is a partial front view of a conventional gate valve.
[Explanation of symbols]
21: Insertion hole
32: Bellows assembly
33: Bellows locking device
34: Bellows
35: Bellows holder
37: Small hole
45: annular groove
47: Inclined lower wall
53: Screw hole
54: Conical set screw

Claims (4)

The shaft is inserted into the insertion hole of the operation body, the lower end of the shaft is connected to the lever member, a bellows assembly is disposed between the inner surface of the insertion hole and the outer surface of the operation body of the shaft, and air is supplied into the operation body. In the gate valve in which the cylinder is arranged, the shaft is connected to the piston rod of the air cylinder, and the shaft moves up and down and swings.
The bellows latch of the bellows assembly is fitted to the operation body, the set screw is screwed into the screw hole of the upper end protruding part of the lever member, and the thrust of the set screw acts on the annular groove on the outer periphery of the bellows holder. An easily maintainable gate valve, wherein the holder is connected to the lever member in an airtight state. The inclined lower wall of the annular groove on the outer periphery of the bellows holder is inclined radially outward and downward, the thrust of the set screw acts on the inclined lower wall, and the lower surface of the bellows holder presses against the annular surface of the lever member. 2. The easy-maintenance gate valve according to claim 1, wherein the lower surface of the bellows holder and the annular surface are sealed by an O-ring, and the lever member and the shaft are sealed by an O-ring. The shaft is inserted into the insertion hole of the operation body, the lower end of the shaft is connected to the lever member, a bellows assembly is disposed between the inner surface of the insertion hole and the outer surface of the operation body of the shaft, and air is supplied into the operation body. In the gate valve in which the cylinder is arranged, the shaft is connected to the piston rod of the air cylinder, and the shaft moves up and down and swings.
The bellows latch of the bellows assembly is fitted to the operation body, the set screw is screwed into the screw hole of the upper end protruding part of the lever member, and the thrust of the set screw acts on the annular groove on the outer periphery of the bellows holder. An easily maintainable gate valve characterized in that the holder is connected to the shaft in an airtight state. The inclined lower wall of the annular groove on the outer periphery of the bellows holder is inclined radially outward and downward, the thrust of the set screw acts on the inclined lower wall, and the lower surface of the bellows holder presses against the annular surface of the lever member. The easy-maintenance gate valve according to claim 3, wherein the space between the bellows holder and the large diameter portion of the shaft is sealed by an O-ring.

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