JP5361627B2 - Vacuum valve housing and vacuum valve - Google Patents

Abstract

Disclosed are a vacuum valve housing having small outer dimensions and a low cost of production, and a vacuum valve configured from said housing. The housing is characterized by an indentation provided to the central section of at least one surface of the cuboidal housing, an aperture surface provided to the central section of the bottom surface of the aforementioned indentation, and port holes that are provided to the outside of the outer perimeter of the aforementioned aperture surface and are for affixing flanges from other tubing.

Description

  The present invention relates to a vacuum valve used for the purpose of switching an exhaust system when a vacuum vessel is evacuated by a vacuum pump, and a casing constituting the vacuum valve.

  Conventionally, for example, Patent Document 1 discloses a vacuum valve. As shown in FIG. 1, this type of valve usually includes a valve body 3 that moves in a longitudinal direction inside a hollow cylindrical housing 2 by a piston rod 1, and an exhaust port 4 that is opened and closed by the valve body 3. A hollow cylindrical body 5 provided on the end surface in the longitudinal direction of the body 2 and provided with a flange portion on the side surface of the housing 2 is erected, and an opening surface 6 serving as an exhaust port is formed on the end surface. It is configured as an L-type vacuum valve.

  In the case of the structure in which the hollow cylindrical body 5 is erected on the side surface of the housing 2 as described above, there has been a problem that the external dimension of the valve becomes large. Further, since at least two hollow cylindrical members 2 and 5 are joined by welding, a gas discharged from the welded portion in a vacuum atmosphere becomes a problem, and a vacuum valve for high vacuum and / or high purity gas is used. There was a problem that it could not be used.

JP 2001-324051 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a vacuum valve housing having a small outer diameter and low manufacturing cost without welding, and a vacuum valve composed of the housing.

According to a first aspect of the present invention, there is provided a solution according to claim 1, wherein a concave portion is provided in a central portion of at least one surface of a rectangular parallelepiped housing, an opening surface is provided in a central portion of a bottom surface of the concave portion, A bolt hole for fixing a flange of another pipe is provided on the outside.
The present invention according to claim 2 is the vacuum valve casing according to claim 1, wherein the casing is obtained by cutting an aluminum or aluminum alloy block. .
According to a third aspect of the present invention, in the vacuum valve casing according to the first or second aspect, the casing is made of aluminum or an aluminum alloy, and the flow path surface formed in the casing is an anode. It is characterized by being oxidized.
According to a fourth aspect of the present invention, in the vacuum valve casing according to the first aspect, the casing is obtained by forging or casting .
Also, a vacuum valve of the present invention, as described in claim 5, characterized in that it is composed of the vacuum valve housing according to any one of claims 1 to 4.

  According to the present invention, it is possible to provide a portion for connecting to the piping without protruding from the housing, and it is possible to save space of the vacuum valve. In addition, since the valve housing can be manufactured without welding the two members, it is possible to reduce the emitted gas in a vacuum atmosphere.

Side sectional view of a conventional vacuum valve (A) Side sectional view of the vacuum valve of one embodiment of the present invention (b) Bottom view (c) Right side view Explanatory drawing of the manufacture example of the valve | bulb housing | casing for vacuum of other embodiment of this invention. Explanatory drawing of the modification of embodiment described in FIG.

The vacuum valve housing of the present invention has a rectangular parallelepiped shape, preferably a cubic shape, and functions as a vacuum valve by including a valve body and a valve seat in the housing.
A vacuum valve according to an embodiment of the present invention will be described below together with the valve housing with reference to the drawings.
The vacuum valve according to an embodiment of the present invention shown in FIG. 2 has a cylindrical shape (not shown) having an axis perpendicular to the bottom surface 10a at the center of the bottom surface 10a of the substantially cubic housing 10. , A cylindrical shape) recess 10u-1 is provided, and an opening surface 11 (hereinafter referred to as "valve opening surface") is provided at the center of the bottom surface of the recess 10u. Bolt holes 26 are drilled outside the outer periphery of the valve opening surface 11 so that the intervals are uniform as shown in FIG.
In addition, a flow path is formed from the valve opening surface 11 toward the inside of the housing 10, and the flow path is formed so that a cross section becomes narrow at a portion orthogonal to the flow path provided in the lateral direction, A valve seat 12 is formed at this site.
The valve body 13 that sits on the upper surface of the valve seat 12 and opens and closes the valve is fixed to the tip of the piston rod 14 inserted from the upper surface of the housing 10. In the illustrated example, the upper portion of the valve body 13 is fixed to the flange portion at the distal end portion of the piston rod 14 to be fixed. Further, a groove along the outer periphery of the valve body 13 is formed on the lower surface. By providing a ring-shaped seal member 15 in the groove, a seal when the valve body 13 comes into contact with the valve seat 12 is provided. Sexuality is enhanced. The upper wall 10h of the housing 10 is provided with a through hole 16 through which the piston rod 14 is inserted. A seal member 17 is also provided on the inner peripheral surface of the through hole 16 so as to pass through the piston rod 14. The sealability with the hole 16 is enhanced. Further, a sealing member such as an O-ring is also provided on the joint surface between the upper wall 10h constituting the upper surface of the housing 10 and the side walls (10d and 10f in the figure) constituting the side surfaces of the housing 10 for the same purpose. It is inserted.

  As described above, a flow path is formed in the housing 10 in the lateral direction, and this flow path terminates at the opening surface 18 on the right side surface 10b of the housing 10 and terminates at the opening surface 20 on the left side surface. . Since the opening surfaces 18 and 20 have the same form in the present embodiment, the following description will focus on the opening surface 18. The opening surface 18 is formed at the center portion of the bottom surface of the concave portion 10u-2 having a cylindrical shape (cylindrical shape in the figure) formed at the center portion of the right side surface as with the bottom surface 10a. Bolt holes 24 are perforated on the outside of the outer periphery of the opening surface 18 so that the intervals are even, as shown in FIG.

  In the present embodiment, the bottom surface 10a and the right side surface 10b of the housing 10 are provided with the recesses 10u-1 and 10u-2, respectively, so that the bottom surface 10a and the right side surface 10b of the rectangular parallelepiped housing 10 are provided. There is no need to provide a projection provided with an opening for connecting piping or the like. Further, since it is not necessary to weld the projection, it is useful as a vacuum valve. Furthermore, since the housing | casing 10 becomes a rectangular parallelepiped shape containing a cube, it becomes easy to convey and handle.

The concave portions 10 u-1 and 10 u-2 provided in the housing 10 described above may be at least one of the planes constituting the housing 10.
Further, the planar shapes of the recesses 10u-1 and 10u-2 are circular in the illustrated ones (FIGS. 2B and 2C), but may be any shape that can accommodate the pipes to be connected. There is no particular limitation. Further, the intervals between the bolt holes 24 and 26 formed in the inner peripheral portions of the bottom surfaces of the recesses 10u-1 and 10u-2 are not necessarily provided at equal intervals as long as the airtightness of the connection portion can be maintained. In addition, a metal film or Tafram (registered trademark) (an anodized fluorine resin is used on the inner peripheral surface of the recesses 10u-1 and 10u-2 including the inner peripheral surfaces of the bolt holes 24 and 26 in order to increase the durability of the connection portion. And the like.
In addition, the rectangular parallelepiped shape of the housing | casing 10 in this specification shall mean the shape by which the valve opening surface 11 and 4 surfaces (housing | casing side surface) orthogonal to this were comprised by the plane. As shown in FIG. 2 (a), the plate member 10h constituting the upper surface of the casing 10 is usually configured integrally with a drive mechanism 22 such as a valve body 13, a piston cylinder 14 and an air cylinder. This is because a slight level difference is generated because the bolt 19 is fixed from the upper surface side.

Moreover, it is preferable that the structural member of the said housing | casing 10 is obtained by cutting from a rectangular parallelepiped thru | or cube aluminum or aluminum alloy block. This is because when a plurality of plate members are joined together by welding, the amount of released gas increases and it becomes difficult to keep the sealing performance of the internal flow path high.
An example will be described with reference to FIG. 2. A box having an upper surface opening excluding the upper wall 10 h of the housing 10, that is, a bottom wall 10 c and four side walls standing around it (the illustrated one is The two side walls 10d, 10f) and the upper wall 10h are obtained by cutting a block made of aluminum or an aluminum alloy. In this case, the recesses 10u-1, 10u-2, the through hole 16, and the opening surfaces 18, 20 are also formed by cutting.

  Moreover, it is preferable that the housing 10 is made of aluminum or an aluminum alloy, and the flow path surface formed in the housing is anodized. This is because a film can be reliably formed by going around to the surface of the flow path inside the housing 10. Moreover, it is because sufficient film | membrane can be formed also on the member surface obtained by cutting.

In the anodic oxidation treatment, an object to be treated is immersed in an alkaline solution and anodized with spark discharge to form an oxide film on the surface of the object to be treated. The process includes a step of performing a predetermined time with a voltage and a step of performing a predetermined time with another voltage lower than the first voltage according to the current density.
Examples of the alkaline solution electrolyte include disodium hydrogen phosphate, sodium tripolyphosphate, sodium dihydrogen phosphate, sodium ultrapolyphosphate, sodium silicate, potassium hydroxide, sodium diphosphate, and triphosphate. One in which sodium, sodium aluminate, sodium metasilicate, sodium hydroxide, or the like is dissolved in water can be used.

In addition, aluminum or aluminum alloy is used as the object to be processed, but aluminum alloy casting materials and die-casting materials, typically silicon, contain a large number of elements that are generally contained, forming a porous anodic oxide film. It is said that it is difficult.
According to the present invention, it is possible to form a coating film with good corrosion resistance even in such a casting or die-casting with a lot of silicon. Further, among the wrought materials, the No. 4000 series treatment of the Al—Si alloy has a poor corrosion resistance due to the same reason, but according to the present invention, a good oxide film can be formed. The wrought material, in which silicon is not precipitated, and aluminum alloys in the 1000th to 3000th, 5000th to 7000th range, are also effective in the case of a complicated shape or a high temperature of 100 ° C. or higher.

In the anodic oxidation treatment, an object to be treated is immersed in an alkaline solution and anodic oxidation treatment involving spark discharge is performed. At this time, a predetermined voltage is applied at a first voltage (a (V)) of 200 V or higher. And a step of performing a predetermined time process at another voltage (b (V)) lower than the first voltage according to the current density. Specifically, while monitoring the current density (iA / cm ² ), other values with a desired value of 100% or less (for example, 80%) with respect to the current density at the start of the first voltage processing A target current density for switching to a voltage is set, and when that current density is reached, that is, when the current density drops to a predetermined current density, it is lower than the first voltage (a (V)). The voltage is lowered to the voltage (b (V)), and the processing is continued at that voltage. The current density at the start of the first voltage treatment is preferably in the range of 0.02 A / cm ^{2 to} 0.1 A / cm ² . If it is less than 0.02 A / cm ² , the voltage may not increase and discharge may not occur. If it exceeds 0.1 A / cm ² , the voltage increases and the formed film is destroyed by discharge, resulting in a rough coating structure and corrosion resistance. Because it gets worse. In addition, the process by another voltage should just be once or more, and the method of dropping to another voltage may be stepwise or linear. Further, as described above, the processing time by the first voltage is continued until the predetermined current density is reached, and the processing time by the other voltages is, for example, 100 with respect to the initial current density (iA / cm ² ). It continues until it becomes the current density of the desired value (for example, 30-40% etc.) below%. The processing time by the first voltage is usually 10 minutes or more.
In addition, the voltage and current waveforms to be applied may be alternating current, direct current, or superposition of alternating current and direct current. In the case of alternating current, the current or voltage may be either a sine wave or not a sine wave.
As described above, by processing at a constant voltage, it is possible to form an oxide film sequentially where current flows easily, i.e., where no oxide film is formed, and indented parts or penetrations of the object to be processed. An oxide film can be formed even on the inner surface of the hole without disposing an electrode in the hole.

  The other voltage is preferably 200V to 400V. If the voltage exceeds 400 V, the film thickness can be increased, but the formed film is destroyed by electric discharge, and it is difficult to attach through holes provided in the object to be processed or complicated electrodes. This is because the film cannot be grown and the film structure becomes rough and the corrosion resistance deteriorates. Moreover, when it is less than 200 V, discharge does not occur, and only a thin film having a thickness of about 200 nm can be formed, resulting in poor corrosion resistance.

Further, it is preferable to increase the voltage to a constant current density.
Furthermore, the member on which the oxide film is formed is preferably heated at 150 ° C. to 500 ° C. in the atmosphere. This is because the formed oxide film can be made denser to improve the corrosion resistance. The reason why the above range is adopted is that oxidation is not accelerated when the temperature is lower than 150 ° C., and energy is consumed only when the temperature exceeds 500 ° C., and a great effect cannot be expected.

Further, the housing 10 may be obtained by forging or casting. This is because the manufacturing cost is lower than that of cutting out from a metal block, the gas released from the welded portion can be eliminated, and the sealing performance of the internal flow path can be improved.
In the case of forging molding, in order to simplify the process, the box described in the above cutting process and the plate material constituting the upper wall 10h provided with the through hole 16 of the piston rod 14 are molded separately. It is preferable. Moreover, in order to simplify a process, it is preferable that the inside of the housing 10 has a shape without an undercut.

Furthermore, as shown in FIG. 3, the box may be formed by sheet metal processing. In this case, from one flat plate 25 or one pipe shown in FIG. 4A, as shown in FIGS. Can be formed.
Specifically, as shown in FIG. 4B, shallow drawing is performed using a mold having a circular, elliptical, or quadrangular cross-sectional shape, and deep drawing (FIG. c)), bottomed bottom holes 24a, 26a to be taps of the bolt holes 24, 26 are formed by burring ((d) in the figure), and taps are formed on the inner peripheral surfaces of the bottom holes 24a, 26a ( (E)), the C-ring groove 28 and the O-ring groove 29 are formed on the inner periphery from the opening side by machining, and further, the valve opening surface 11 and the opening surface 18 are formed by machining (the same figure). (F)).
After that, as shown in FIG. 2, a cylinder unit driven by air or the like, which is configured by inserting the piston rod 14 through the plate 10f and providing the valve body 13 at the tip of the piston rod 14, is mounted on the box. It becomes a vacuum valve.
In the step (d), the tap hole 26a is formed by being pressed and extended from the bottom surface side of the housing 10, and when the valve opening surface 11 is punched in the step (f), the pilot hole 26a is formed. The flange 25a of 26a is preferably used as the valve seat 12. This is because the process can be simplified.
In addition, without providing the C-ring groove 28 in FIG. 3 (f), as shown in FIG. 4, a tap 30 for bolting the plate material constituting the upper wall 10h is formed on the flange of the box. It may be.

DESCRIPTION OF SYMBOLS 1 Piston rod 2 Housing | casing 3 Valve body 4 Exhaust port 5 Hollow cylindrical body 6 Opening surface 10 Housing | casing 10a Housing bottom surface 10b Housing | casing right side surface 10u-1 Bottom surface recessed part 10u-2 Right side surface recessed part 10c Bottom wall 10d Side wall 10f Side wall 10h Upper wall 11 Opening surface (valve opening surface)
12 Valve seat 13 Valve body 14 Piston rod 14a Piston rod flange 15 Seal member 16 Through hole 17 Seal member 18 Opening surface (right side surface)
19 Bolt 20 Second opening surface (opening surface opposite to the first opening surface)
22 Drive mechanism 23 Bolt 24 Bolt hole 25 Flat plate 26 Bolt hole 27 Sealing member 28 C-ring groove 29 O-ring groove 30 Tap

Claims (5)

  A bolt hole for providing a recess at the center of at least one surface of a rectangular parallelepiped housing, providing an opening at the center of the bottom of the recess, and fixing a flange of another pipe outside the outer periphery of the opening A vacuum valve housing characterized in that   The vacuum valve casing according to claim 1, wherein the constituent member of the casing is obtained by cutting a block of aluminum or aluminum alloy.   The vacuum valve casing according to claim 1 or 2, wherein the casing is made of aluminum or an aluminum alloy, and a surface of a flow path formed in the casing is anodized.   2. The vacuum valve casing according to claim 1, wherein the casing is obtained by forging or casting. A vacuum valve comprising the vacuum valve housing according to any one of claims 1 to 4 .

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