CN1955519A

CN1955519A - Vacuum valve

Info

Publication number: CN1955519A
Application number: CNA200610135695XA
Authority: CN
Inventors: 柳川正史; 生路教典; 池尾利洋
Original assignee: CKD Corp
Current assignee: CKD Corp
Priority date: 2005-10-25
Filing date: 2006-10-23
Publication date: 2007-05-02
Anticipated expiration: 2026-10-23
Also published as: CN100425890C; KR101098916B1; KR20070044787A; JP2007120522A; JP4790374B2

Abstract

The present invention provides an compact vacuum valve with long life and low cost. The vacuum valve(1)comprises a cylinder body(12); a first port(32), a second port(33), a valve seat part(34)which are provided on the valve body(31); and a valve body(24)connected with a movable shaft(23)and provided with a sealing element(35)contacting or departing from the valve seat part(34). The cylinder body(12)has a first piston(45)and a second piston(46)which are pressed to move by supplying pressure fluid to a first operating port(25). When the second piston(46)contacts with the inner contact face(21d)of the cylinder, the first piston(45)further moves towards the side to separate the first port(32)and the second port(33)because a space is formed between the first piston(45)and the end contact face(45d). Only the racking force of the first piston(45)serves as the pressure applied to the sealing element(35)contacting the valve seat part(34).

Description

Vacuum valve

Technical field

The valve that the present invention relates to a kind of vacuum valve opens and closes the propelling force generating means.

Background technique

For example, in semiconductor manufacturing process, when making the inner pressure relief of vacuum chamber,, connecting vacuum valve, opening and closing stream by this vacuum valve with in these vacuum chambers and the stream that vacuum pump is connected by vacuum pump.

The vacuum valve that is used for such purposes, the piston rod that is generally cylinder body is connected the structure that is driven by the piston rod movement of cylinder body with the valve member that opens and closes stream.

Using the reason of cylinder body for the driving force that opens and closes vacuum valve is to adopt better simply structure just can realize bigger thrust at low cost.

The driving mode of the cylinder body of such vacuum valve has these 3 kinds of normal close types, open type, reciprocating motion type, and is selected according to purposes respectively.

The vacuum valve of normal close type just can drive cylinder body by propellant is supplied with to one-sided valve chamber at one-sided use spring, and when not supplying with propellant, vacuum valve just becomes closed condition.Therefore, be used for when power supply disconnection and gas extraction, by closing vacuum valve, with situation towards the secure side action.

In addition, the vacuum valve of open type is supplied with propellant to one-sided valve chamber equally, by at one-sided use spring, drives cylinder body, and when not supplying with propellant, vacuum valve becomes opening state.The vacuum valve of such open type is used for the usage mode according to the user, when opening vacuum valve, towards the situation of secure side action.

In addition, the vacuum valve of reciprocating motion type comes open and close valve to the valve chamber supply propellant of both sides.The vacuum valve of such reciprocating motion type is used for the difference according to user's security consideration, when power supply disconnects, cuts off situation of vacuum valve etc. reliably by the pressure of propellant.

In these 3 kinds of modes, the most frequently used is normal close type.But open type, reciprocating motion type also have demand according to the design difference of production line.,, prepare custom-designed parts, can improve the cost of open type and reciprocating motion type because of demand does not have so muchly.

According to such fact, even being benchmark with the normal close type, vacuum valve designs,,, can reduce cost also by for example making cylinder diameter generalization etc. for the driving mode of open type or reciprocating motion type normal close type and parts generalization.

Vacuum valve one example as in the past shows patent documentation 1.

The vacuum valve of patent documentation 1 is the load rating seal arrangement that high vacuum shown in Figure 13 is used valve, at the load rating lower seal, adopts the vacuum valve of the reciprocating motion type of leaf spring.

The vacuum valve of patent documentation 1 is, forms a plurality of ports that are communicated with the valve chamber 111 of valve body 100 by pipe portion, makes driver that valve rod 119 moves and valve body in abutting connection with configuration.Form valve seat with on valve chamber and the stream that a side pipe portion is connected, contact with valve seat by making the caulking gum on the valve body that is installed on valve rod 119 cardinal extremities, stream is closed, and lifts off a seat by the caulking gum that makes valve body, and stream is unlocked.

The driving force of driver is transmitted to valve rod 119 from driver part 125 by leaf spring 101, driver part 125 can be installed round valve rod 119 free to-and-fro motion ground, limit amount of movement simultaneously, can not surpass established amount to the load that valve rod 119 transmits from driver part 125.

Like this, to be no more than established amount be in order to protect caulking gum to the load of transmitting to valve rod 119 from driver part 125.

Have only decrement on the caulking gum, when decrement is not enough, can produce leakage, and decrement can promote rubber deterioration when excessive.And, when maintaining optimum decrement, the working pressure of superheated steam need be limited in the narrow and small scope.

, under for the pressure of keeping the superheated steam that optimum decrement sets, can not obtain making vacuum valve to be in the thrust that opening state is used, vacuum valve can not be in opening state.For this reason, in patent documentation 1, determine to make vacuum valve be in the pressure range of the superheated steam of opening state, when making vacuum valve be in closed condition, be provided with and make the leaf spring 101 that can not surpass established amount from driver part 125 to the load of valve rod 119 transmission, absorbing the part of its load, and keep the only decrement of caulking gum.

Then patent documentation 2 shows an example of other vacuum valve.

The vacuum valve of patent documentation 2 by making up 2 cylinder body functions, can carry out the aperture adjustment for adjusting 2 port vacuum valves of aperture as illustrated in fig. 14.

The vacuum valve of patent documentation 2 is, in the 202a of piston chamber of cylinder body 202, take in the 1st piston 215 and the 2nd piston 232, the 1st piston 215 is connected with the main valve parts 214 of switch primary flow path 206, the 2nd piston 232 with have the 2nd rod member 242 that the position can freely regulated retainer 243 and be connected, to the 2nd pressure chamber 240 supply pressure fluids, make the 2nd piston-advance up to retainer 243 with till contacting part 239b contacts, by under this state, to the 1st pressure chamber 229 supply pressure fluids, make the 1st piston 215 advance to the 2nd piston 232 position contacting till, thereby 214 degree with the stroke X of the 1st piston 215 of main valve parts are driven valve.

In addition, has the secondary valve system 208 that restrictively opens and closes above-mentioned primary flow path 206, by in the 1st piston 215, sub-piston 248 being set, the secondary flow road 206A that is arranged on the main valve parts 214 is carried out switch, can realize the slow exhaust of the vacuum chamber that is connected with vacuum valve.

That is, be constructed as follows structure: by making the 1st piston 215 and 232 combinations of the 2nd piston and can freely advancing separately, valve body at random can be stopped on 3 positions, and be provided with secondary flow road 206A, can realize slow exhaust by sub-piston 248 switches.

Patent documentation 1: Japanese kokai publication hei 10-220640 communique

Patent documentation 2: TOHKEMY 2004-44727 communique

Summary of the invention

But,, exist following technical problem for conventional art.

(1) in the reciprocating motion type vacuum valve, can not set the optimum load range when closing valve.

As above-mentioned, consider that from the viewpoint of cost and maintenance component management etc. the vacuum valve of normal close type, open type, reciprocating motion type will make parts general.

But, make the general problem that also exists of parts.

In vacuum valve, the switch of valve advances load to be determined by the compression area of the piston that possesses in the vacuum valve and the long-pending of pressure of propellant.

When drive unit adopted the cylinder body of reciprocating motion type, when valve was opened, the difference of cylinder diameter and piston rod external diameter became the compression area of piston, need make piston power that rises and the power that overcomes the hydrodynamic pressure in the inflow valve body.And valve is when cutting out, and cylinder diameter becomes the compression area of piston, need make power that piston descends and the power that the caulking gum that possesses on the valve body is flattened.When having bellows on the vacuum valve, when opening of valves, when valve cuts out, further need make the flexible power of bellows.

That is, in the vacuum valve of reciprocating motion type, the optimum load range when closing with valve during opening of valves is different, and usually, the power when the force rate valve that needs during opening of valves cuts out is big.According to design, also have when opening of valves the different situation of required power several times when closing with valve.

But vacuum valve then can not be realized function as can not switch valve, thereby matches during with more energetically opening of valves of needs and design.

Vacuum valve contacts and flattens caulking gum by making the caulking gum that possesses on the valve body with valve seat, but cut-off valve cuts off stream.

That is, under the recuperability effect of the caulking gum that flattens, with the full week sealing of valve seat, to cut off fluid.

, the elastic force of caulking gum can lose efficacy by flattening repeatedly when the vacuum valve switch, and caulking gum becomes the state of flattening, can not seal.Such deterioration takes place when caulking gum is applied excessive power easily.The deterioration of caulking gum can make the fluid interrupting performance of vacuum valve reduce, and can not realize the function as vacuum valve, when the caulking gum deterioration, needs to change caulking gum.

That is, when the power when valve cuts out was optimum, the deterioration of caulking gum existed the problem that must change caulking gum continually in advance.

For this reason, when using the vacuum valve of reciprocating motion type, also consider to use regulator, make the gas drops of supplying with the propellant side, but adopt this method, need to be provided with in addition to push away regulator, also need the extra space that is provided with when vacuum valve cuts out.

In patent documentation 1,, solve this technical problem by adopting leaf spring 101 at this problem.

And the invention of patent documentation 2 is because of being that seal load is adjusted purpose, therefore is not the solution of such problem.

Need to adjust during (2) because of assembling, cost uprises.

Yet in patent documentation 1, for the employed leaf spring 101 of the problem that solves (1), when leaf spring 101 is assembled to vacuum valve, the relation of the deflection of needs adjustment leaf spring 101 and the decrement of caulking gum.Although in patent documentation 1, there is not so direct record, in fact consider goods error etc., the goods error of the error ratio machining of the O type ring goods that use as caulking gum wants big, and the piston position that obtains optimum decrement might not.On the other hand, because of leaf spring 101 has bigger spring modulus, have under the variation of amount of deformation slightly, the character of the bigger variation of active force that produces in order to obtain the proper compression amount, considers to need regulating mechanism, the adjustment in the time of need assembling.

But such adjustment means and the decrement of leaf spring 101 and the individual difference of goods will be carried out inching adaptably, therefore is adjusted into the action need man-hour in the proper range.

Such adjustment operation can increase cost because of needing during assembling when assembling, the result, and the cost that causes goods improves, and not preferred.

The claimant has considered to use the vacuum valve as the O type ring of Figure 12 in order to solve the problem of (1).In this method, in cylinder barrel, further be provided with an O type ring 300 on the surface of contact 21d, at sealed member 35 that possess, that be equivalent to above-mentioned caulking gum on the valve body 24 with after seat portion 34 contacts, the O type ring 300 that possesses on the surface of contact 21d in piston portion 22 and the cylinder barrel contacts, sealed member 35 flattens by the time difference with O type ring 300, the decrement of control sealed member 35 reduces the pressure of sealed member 35.

According to the method, because sealed member 35 and O type ring 300 these two elastomers are accepted the thrust of valve body, having offseted is applied to power on the sealed member 35, compares with the method for patent documentation 1, construct simpler, thereby have advantage cheaply., very important because of sealed member 35 with the position relation of O type ring 300, need carry out the adjustment of decrement.

Therefore, although simple structure and compare and can reduce cost with patent documentation 1 because of also needing to adjust, does not change aspect assembly cost.

In addition, as the other means that alleviate the burden of caulking gum, also consider the method that the diameter of cylinder with the drive portion of vacuum valve dwindles.According to this method,, also can reduce cost owing to only make the diameter of cylinder body less.

But in order to suppress to make the diameter of cylinder body less from the pushing force of propellant, when reducing the compression area of piston, although alleviated the burden of caulking gum when stream cuts off, the result is when stream is communicated with, also can reduce the power that makes the valve body action.Therefore, press according to the vacuum of in vacuum chamber that connects with vacuum valve or vacuum pump, using different, when stream is open, may not poppet body, need to increase the pressure of propellant, also need to prepare other pressure charging valve etc. and the assembling loop of boosting.That is, the pressure of propellant is reduced or compression area is reduced, can influence action, and become the factor that other problems takes place.

Promptly, in example that conventional art or above-mentioned claimant propose etc., as above-mentioned, be difficult in the mechanism that the power that will the caulking gum that possess on the valve body as consumable part be applied is suppressed be set in the reciprocating motion type vacuum valve, with at opening of valves the time and valve obtain optimum load range under the both of these case when closing.

When the caulking gum that possesses on to valve body applies power more than necessary, the lost of life of caulking gum, generation such as must keep in repair continually at problem, becomes the problem of the user being added burden.

Therefore, solved such problem among the present invention, it is a kind of when opening of valves and valve when closing under the both of these case that its purpose is to provide, can be with the vacuum valve of the load range optimization that applies on the valve body.

To achieve these goals, vacuum valve of the present invention has following feature.

(1) a kind of vacuum valve, have with valve body and be connected and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that, described cylinder body have combine with described movable axis and compression area less than the 1st piston of the cylinder inner face sectional area of described cylinder body, with the 2nd piston that engages with described movable axis and pressure by pressure fluid makes described the 1st piston move indirectly; Supply with described pressure fluid by the 1st operation port that on described cylinder body, possesses, described the 1st piston and described the 2nd piston pressurized, described the 1st piston slides on the recess inwall that described the 2nd internal piston possesses, described the 2nd piston slides on the cylindrical part internal face of described cylinder body, and described thus the 1st piston and described the 2nd piston move; When described the 2nd piston contacts with retainer with the 2nd piston that described the 1st port and described the 2nd port is cut off a side, cut off the 1st piston of a side with having the space between the retainer owing to described the 1st piston and with described the 1st port and described the 2nd port, thereby the 1st piston further towards described the 1st port and described the 2nd port are cut off a side shifting, the pushing force of only described the 1st piston becomes the racking that the described sealed member that contacts described valve seat is applied, and described the 1st port and described the 2nd port are cut off.

At this, " combining " meaning with described movable axis is, movable axis physically engages with the 1st piston, on the 1st piston, carve when establishing screw thread, or carve when establishing screw thread and using bolted joints in the movable axis side, as simple engagement means, can stop the 1st piston with the relative movable axis of the mode that does not unload with parts such as stop rings, keep with some loosening state.

In addition, at this, " sealed member " be, for example the elastic member of O type ring-type or have the parts of sealing functions such as metal-containing Sealing.Under situation of the present invention, the sealed member that possesses on the valve body is contacted with valve seat, by flatten with and valve seat between seamlessly seal.The such elastic member of O type ring is realized sealing function by pushing force to flatten O type ring.Under the situation of metal seal, the distortion under O type ring situation requires the parallelism of valve body and valve seat and planeness separately, but as from microcosmic, metal seal is being urged and is being out of shape, and produces sealing function.Therefore, the function of cutting off fluid all can realize in either event.In addition, usually in order to cut down finished cost, as O type ring, use the big sealed member of amount of deformation.

(2) a kind of vacuum valve, have with valve body and be connected and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that, described cylinder body have combine with described movable axis and compression area less than the 1st piston of the cylinder inner face sectional area of described cylinder body, with the 2nd piston that engages with described movable axis and pressure by pressure fluid makes described the 1st piston move indirectly; The 1st piston is in the inboard of described the 2nd piston, and the periphery of described the 1st piston is connected by flexible film in interior week with described the 2nd piston; Supply with described pressure fluid by the 1st operation port that possesses on described cylinder body, described the 1st piston and described the 2nd piston pressurized move; When described the 2nd piston contacts with retainer with the 2nd piston that described the 1st port and described the 2nd port is cut off a side, cut off the 1st piston of a side with having the space between the retainer owing to described the 1st piston and with described the 1st port and described the 2nd port, thereby the 1st piston further towards described the 1st port and described the 2nd port are cut off a side shifting, the pushing force of only described the 1st piston becomes the racking that the described sealed member that contacts described valve seat is applied, and described the 1st port and described the 2nd port are cut off.

At this, " flexible film " refers to diaphragm or has flexual films such as bellows.The 1st piston and the 2nd piston can be realized sealing as the structure of the slip surface (1) by being connected by diaphragm etc.

(3) a kind of vacuum valve, have with valve body and be connected and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that, described cylinder body have combine with described movable axis and compression area less than the 1st piston of the cylinder inner face sectional area of described cylinder body, with the 2nd piston that engages with described movable axis and pressure by pressure fluid makes described the 1st piston move indirectly; Supply with described pressure fluid by the 1st operation port that on described cylinder body, possesses, described the 1st piston and described the 2nd piston pressurized, described the 1st piston slides on the protuberance wall that possesses on described the 2nd piston, described the 2nd piston slides on the cylindrical part internal face of described cylinder body, and described thus the 1st piston and described the 2nd piston move; When described the 2nd piston contacts with retainer with the 2nd piston that described the 1st port and described the 2nd port is cut off a side, cut off the 1st piston of a side with having the space between the retainer owing to described the 1st piston and with described the 1st port and described the 2nd port, thereby the 1st piston further towards described the 1st port and described the 2nd port are cut off a side shifting, the pushing force of only described the 1st piston becomes the racking that the described sealed member that contacts described valve seat is applied, and described the 1st port and described the 2nd port are cut off.

(4) in the arbitrary described vacuum valve in (1)～(3), it is characterized in that, described the 1st piston has the support that the described cylindrical part internal face with described cylinder body slides, and described support is in described the 1st operating end oral-lateral, has the vent of using by described pressure fluid on the described support.

(5) in the arbitrary described vacuum valve in (1)～(4), it is characterized in that, described the 2nd piston is passed by described movable axis, and be located between described the 1st piston and the described valve body, on described movable axis, has the fastening portion that engages usefulness with described the 2nd piston, engage with the joining portion of described the 2nd piston, the thickness at the described joining portion of described the 2nd piston is littler than the length from described the 1st piston end face to described fastening portion.

At this, " fastening portion " can for, for example on movable axis, implement step processing and stepped part be set, with the fastening joining portion, also can use stop ring with the fastening joining portion.That is, the joining portion of the 2nd piston that thickness is littler than the distance from the 1st piston end face to fastening portion is by being arranged at mobile the getting final product of fastening portion restriction on the movable axis.Thus, the moving range at the joining portion of the 2nd piston is determined by the fastening portion of the 1st piston end face and movable axis.

By having the vacuum valve of the present invention of such feature, can obtain following effect and effect.

(1) because a kind of vacuum valve, have with valve body and be connected and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that, described cylinder body have combine with described movable axis and compression area less than the 1st piston of the cylinder inner face sectional area of described cylinder body, with the 2nd piston that engages with described movable axis and pressure by pressure fluid makes described the 1st piston move indirectly; Supply with described pressure fluid by the 1st operation port that on described cylinder body, possesses, described the 1st piston and described the 2nd piston pressurized, described the 1st piston slides on the recess inwall that described the 2nd internal piston possesses, described the 2nd piston slides on the cylindrical part internal face of described cylinder body, and described thus the 1st piston and described the 2nd piston move; When described the 2nd piston contacts with retainer with the 2nd piston that described the 1st port and described the 2nd port is cut off a side, cut off the 1st piston of a side with having the space between the retainer owing to described the 1st piston and with described the 1st port and described the 2nd port, thereby the 1st piston further towards described the 1st port and described the 2nd port are cut off a side shifting, the pushing force of only described the 1st piston becomes the racking that the described sealed member that contacts described valve seat is applied, described the 1st port and described the 2nd port are cut off, thereby have when opening of valves and valve when closing under the both of these case, make the superior effect of the load range optimization that is applied on the valve body.

When opening of valves and valve when closing under the both of these case, make the effect of the load range optimization that is applied on the valve body, realize by following effect.

When the opening of valves of vacuum valve,, therefore press P by the operation of pressure fluid owing to undertaken by the 1st piston and the 2nd piston ₁Compression area A with the external diameter difference of the internal diameter of cylinder body and movable axis ₂Long-pending A ₂P ₁Determine.

On the other hand, when the valve of vacuum valve cut out, the sealed member that the 2nd piston possesses on valve body contacted with retainer with the 2nd piston, at the compression area A of 1st piston littler than the cylinder inner face sectional area of cylinder body with before seat portion contacts ₁Press P with operation ₁Long-pending A ₁P ₁Pushing force under, the racking that applies towards the sealed member that contacts with seat portion, thereby can carry out pushing in the optimum load range to sealed member.

That is, during opening of valves, be compression area A ₂, when valve cuts out, be compression area A ₁, press P owing to accept the operation of pressure fluid ₁, compression area difference, thereby setting optimum load range separately.

(2) because a kind of vacuum valve, have with valve body and be connected and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that, described cylinder body have combine with described movable axis and compression area less than the 1st piston of the cylinder inner face sectional area of described cylinder body, with the 2nd piston that engages with described movable axis and pressure by pressure fluid makes described the 1st piston move indirectly; The 1st piston is in the inboard of described the 2nd piston, and the periphery of described the 1st piston is connected by flexible film in interior week with described the 2nd piston; Supply with described pressure fluid by the 1st operation port that possesses on described cylinder body, described the 1st piston and described the 2nd piston pressurized move; When described the 2nd piston contacts with retainer with the 2nd piston that described the 1st port and described the 2nd port is cut off a side, cut off the 1st piston of a side with having the space between the retainer owing to described the 1st piston and with described the 1st port and described the 2nd port, thereby the 1st piston further towards described the 1st port and described the 2nd port are cut off a side shifting, the pushing force of only described the 1st piston becomes the racking that the described sealed member that contacts described valve seat is applied, described the 1st port and described the 2nd port are cut off, thereby in fricton-tight portion, when for example connecting the 1st piston and the 2nd piston by diaphragm, by making the 1st piston action, can obtain the effect identical, and can under than the little resistance of the vacuum valve of (1), make the 1st piston action with the vacuum valve of (1).

(3) because a kind of vacuum valve, have with valve body and be connected and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that, described cylinder body have combine with described movable axis and compression area less than the 1st piston of the cylinder inner face sectional area of described cylinder body, with the 2nd piston that engages with described movable axis and pressure by pressure fluid makes described the 1st piston move indirectly; Supply with described pressure fluid by the 1st operation port that on described cylinder body, possesses, described the 1st piston and described the 2nd piston pressurized, described the 1st piston slides on the protuberance wall that possesses on described the 2nd piston, described the 2nd piston slides on the cylindrical part internal face of described cylinder body, and described thus the 1st piston and described the 2nd piston move; When described the 2nd piston contacts with retainer with the 2nd piston that described the 1st port and described the 2nd port is cut off a side, cut off the 1st piston of a side with having the space between the retainer owing to described the 1st piston and with described the 1st port and described the 2nd port, thereby the 1st piston further towards described the 1st port and described the 2nd port are cut off a side shifting, the pushing force of only described the 1st piston becomes the racking that the described sealed member that contacts described valve seat is applied, described the 1st port and described the 2nd port are cut off, can obtain the effect identical with the vacuum valve of (1).

(4) in the arbitrary described vacuum valve in (1)～(3), owing to it is characterized in that, described the 1st piston has the support that the described cylindrical part internal face with described cylinder body slides, described support is in described the 1st operating end oral-lateral, has the vent of using by described pressure fluid on the described support, thereby when valve body is contacted with valve seat, can suppress the sealed member that possesses on the valve body to be contacted with valve seat to the waving of the radial direction of movable axis.

In addition, the compression area of the 1st piston, by be provided with ventilating part on the 1st piston, the cylinder inner face sectional area of comparable cylinder barrel is little.

5, in the arbitrary described vacuum valve in (1)～(4), owing to it is characterized in that, described the 2nd piston is passed by described movable axis, and be located between described the 1st piston and the described valve body, on described movable axis, has the fastening portion that engages usefulness with described the 2nd piston, engage with the joining portion of described the 2nd piston, the thickness at the described joining portion of described the 2nd piston is littler than the length from described the 1st piston end face to described fastening portion, thereby can use simple method, at the 2nd piston with after retainer contacts, obtain the amplitude of the 1st piston action, only can produce the power that the sealed member that possesses on the valve body is contacted with valve seat by the 1st piston.

Description of drawings

Fig. 1 is the sectional view that the vacuum valve under the closed condition among the present invention the 1st embodiment is shown,

Fig. 2 is the sectional view that the vacuum valve under the opening state among the present invention the 1st embodiment is shown,

Fig. 3 is the amplification view that the vacuum valve under the closed condition among the present invention the 1st embodiment is shown, and the 1st piston is in the upper end of stroke,

Fig. 4 is the sectional view that the amplification of the vacuum valve under the closed condition among the present invention the 1st embodiment is shown, and the 1st piston is in the lower end of stroke,

Fig. 5 is the further explanatory drawings that the A portion cross section of Fig. 3 among the 1st embodiment is shown,

Fig. 6 is the further explanatory drawings that the B portion cross section of Fig. 4 among the 1st embodiment is shown,

Fig. 7 is the sectional view that the amplification of the vacuum valve under the closed condition among the present invention the 2nd embodiment is shown, and the 1st piston is in the upper end of stroke,

Fig. 8 is the sectional view that the amplification of the vacuum valve under the closed condition among the present invention the 3rd embodiment is shown, and the 1st piston is in the upper end of stroke,

Fig. 9 is the amplification view that the vacuum valve under the closed condition among the present invention the 4th embodiment is shown, and the 1st piston is in the upper end of stroke,

Figure 10 is the amplification view that the vacuum valve under the closed condition among the present invention the 5th embodiment is shown, and the 1st piston is in the upper end of stroke,

Figure 11 is the sectional view that the amplification of the vacuum valve under the opening state among the present invention the 5th embodiment is shown, and the 1st piston is in the upper end of stroke,

Figure 12 illustrates the sectional view of vacuum valve that the claimant proposes in the example to adjust with O type ring the decrement of the sealed member that possesses on the valve body of vacuum valve,

Figure 13 illustrates in the patent documentation 1 sectional view of vacuum valve of adjusting the decrement of the sealed member that possesses on the valve body of vacuum valve with leaf spring,

Figure 14 illustrates the sectional view of adjusting the vacuum valve of cylinder body aperture in the patent documentation 2 with 2 pistons.

Embodiment

(the 1st embodiment)

Below, with reference to accompanying drawing, the 1st embodiment of the present invention is described.At first the formation to the 1st embodiment describes.

Fig. 1 illustrates the sectional view under the 1st embodiment's the closed condition of vacuum valve.Fig. 2 illustrates the sectional view under the 1st embodiment's the opening state of vacuum valve.

And Fig. 3 and Fig. 4 illustrate the enlarged view under the vacuum valve closed condition.

Vacuum valve 1 is made of valve portion 11 and cylinder body portion 12 these 2 parts as shown in Figure 1, and valve portion 11 has the stainless steel of hollow portion or the valve body 31 of aluminum processed goods to constitute by conduct, and the mode that inner face can not retain with inventory of gas has the gap or no concave-convex portion ground is not integrally formed.In addition, cylinder body portion 12 is made of the cylinder barrel 21 with cylinder inner face 21a, is aluminum drawing product.Valve portion 11 and cylinder body portion 12 can adorn by bolt etc. with taking off and be fastenedly connected.

In valve portion 11, be provided with the 1st port part 41 of the general cylindrical shape shape of the 1st port 32 with cylinder body portion 12 mutually opposed places, form the 1st port lip part 41a at the front end of the 1st port part 41.In addition, the 1st port part 42 of the general cylindrical shape shape with the 2nd port 33 is set in valve portion 11 sides, at the front end of the 2nd port part 42 and same the 2nd port lip part 42a that forms on the 1st port part 41.And the 1st port lip part 41a and the 2nd port lip part 42a by forming on the 1st port 32 or the 2nd port 33 are connected with external equipments such as vacuum chamber or vacuum pumps.

Below, the internal structure of valve portion 11 is described.

In the inside of valve body illustrated in figures 1 and 2 31, the 1st port part 41 with the opposed end of the 1st port lip part 41a, be provided with seat portion 34, contact or leave with valve body 24 with the sealed member 35 that can freely load and unload.

Sealed member 35 is the O type ring of viton system, and by sealing and fixing parts 24a, deformable ground is installed on the valve body 24.

Sealing fixed component 24a by bolton to valve body 24.The cross section that sealing and fixing parts 24a installs on the valve body 24 is the dovetail groove shape, becomes the space that keeps sealed member 35.The degree of depth in this dovetail groove shape space is littler than the diameter of section of sealed member 35.That is, under sealed member 35 is installed on state on the valve body 24, become the lip-deep state that sealed member 35 appears at valve body 24 circle-shapedly in seat portion 34 sides.

And, contacting with seat portion 34 by valve body 24, sealed member 35 is crushed on whole circumference, under its recuperability effect, the performance sealing function.

Valve body 24 is connected with movable axis 23, and movable axis 23 drives by cylinder body portion 12.

Between valve body 24 and cylinder body portion 12, be provided with metal bellows 36.

The shape of the retractable that metal bellows 36 is made for stainless steel, the particle that produces when movable axis 23 is slided does not fall in the stream that is communicated with the 1st port 32 and the 2nd port 33, and the end of metal bellows 36 is installed to respectively on valve body 31 and the valve body 24 airtightly.

Below, the internal structure of cylinder body portion 12 is described.

On cylinder barrel illustrated in figures 1 and 2 21, be provided with the 1st operation port 25 and the 2nd operation port 26, the 1 operation ports 25 are communicated with cylinder chamber 27 the 1st, the 2nd operation port 26 is communicated with cylinder chamber 28 the 2nd.And,, be connected with tracheae, and then be connected with compressor by solenoid valve by being installed to the not shown joint on the 1st operation port 25 and the 2nd operation port 26.

Be connected with the piston portion 22 that on the cylinder inner face 21a of cylinder barrel 21 inside, slides with the movable axis 23 of valve body 24 combinations.Therefore, the propellant of being supplied with by not shown solenoid valve is when the 1st operation port 25 or the 2nd operation port 26 are supplied with, and piston portion 22 slides on cylinder inner face 21a, drives the movable axis 23 that is connected with piston portion 22.

Movable axis 23 is keeping slidably by protrude the movable axis holding part 21b that is provided with on cylinder barrel 21, on movable axis holding part 21b, be provided with movable axis and keep liner 21c, slide by movable axis 23, when particulate be difficult to take place, the pressure that has prevented propellant was applied to the situation in the metal bellows 36.

Piston portion 22 is made of the 1st piston 45 that slides on the recess slip surface 46c of the 2nd piston 46, the 2nd piston 46 these 2 pistons of sliding on cylinder inner face 21a.

On the 1st piston 45, form protuberance cylindraceous, on the 2nd piston 46, form recess slip surface 46c cylindraceous.Cylindric protuberance can embed in the recess slip surface cylindraceous.

And, embed the 1st sliding mats 45a at the protuberance of the 1st piston 45, on the recess slip surface 46c of the 2nd piston 46, to slide.

On the 1st piston 45, be provided with wear ring 45b at contacting part with cylinder inner face 21a.In addition, on the 1st piston 45, be provided with a plurality of fluids by hole 45c.

In addition, on the 2nd piston 46, be provided with the 2nd sliding mats 46a and piston magnet 46b, on cylinder inner face 21a, to slide.This piston magnet 46b is used to detect the detection etc. of the not shown recloser of cylinder body position.

And, the 2nd piston 46 connects the movable axis 23 that is connected with the 1st piston 45, and be arranged between the 1st piston 45 and the interior surface of contact 21d of cylinder barrel, on movable axis 23, be provided with step, on the movable axis 23 than with cylinder barrel in the also thin one section stepped part 23a of slide part of surface of contact 21d, engage with the joining portion 46f of the 2nd piston 46.

Be provided with gap S1 between movable axis 23 and the 2nd piston 46, Fig. 5 shows its enlarged view.This gap S1 is, even when valve body 24 relative drawings are vacillated now to the left, now to the right, movable axis 23 and the 2nd piston 46 be the space of interference degrees not also.

In addition, the part that further attenuates from the stepped part 23a of movable axis 23 is carved and is provided with screw thread, to engage with the 1st piston 45.

Therefore, at the stepped part 23a place of movable axis 23, the 2nd piston 46 that engages with joining portion 46f becomes the step that sandwiches movable axis 23 and the shape of the 1st piston 45.

But, to compare to the distance of end surface of contact 45d with stepped part 23a from movable axis 23, the thickness of the joining portion 46f of the 2nd piston 46 is slightly little, and at the rising end of Fig. 2 piston 22, the 2nd piston 46 is looked from drawing, has the space of knee-action only.Decline end at the piston 22 of Fig. 1 also is same.This space is bigger than the decrement of the sealed member 35 that valve body 24 has.

Fig. 3 and Fig. 4 have illustrated the closed condition of vacuum valve 1.And Fig. 5 is the cross-sectional view that the A portion of Fig. 3 amplifies, and Fig. 6 is the cross-sectional view that the B portion of Fig. 4 amplifies.

Fig. 3 shows the position of mobile upper end under the surface of contact 21d contact condition, the 1st piston 45 in the 2nd piston area 46d of the 2nd piston 46 and the cylinder barrel.

Position on should moving is determined by the space of stepped part 23a and joining portion 46f as shown in Figure 5.

In addition, Fig. 4 shows the position of mobile lower end under the surface of contact 21d contact condition, the 1st piston 45 in the 2nd piston area 46d of the 2nd piston 46 and the cylinder barrel.

Promptly, in the closed condition of vacuum valve 1 shown in Figure 1, the 1st piston 45 is under the propellant effect of supplying with cylinder chamber 27 the 1st, receive pressure, the sealed member 35 that the valve body 24 that is connected with the 1st piston 45 by movable axis 23 is possessed contacts with seat portion 34, the 1st piston 45 is by movable axis 23 and valve body 24, and sealed member 35 transmits pushing force relatively.

At this moment, as shown in Figure 6, the joining portion 46f that the 2nd piston 46 is possessed does not contact with the stepped part 23a that movable axis 23 is possessed, can have the 1st space X ₁With the 2nd space X ₂Mode determine the size of each parts.The 1st space X ₁+ the 2 space X ₂Greater than the decrement of sealed member 35, in the 1st embodiment, be set at about 2 times of decrement.

That is, sealed member 35 contacts with seat portion 34, and under the state of the decrement that gives appropriateness, the relation of stepped part 23a and joining portion 46f is because of also existing the 1st space X ₁With the 2nd space X ₂The 2nd piston 46 can not pass to power movable axis 23, just applying under the state of pushing force, determine the shape and size of movable axis 23, valve body 24, sealed member the 35, the 1st piston the 45, the 2nd piston 46 with 45 pairs of sealed members 35 of movable axis 23 direct-connected the 1st pistons.

Below, the effect of the 1st embodiment's of above-mentioned formation vacuum valve 1 is described.

At first, the situation that vacuum valve 1 is in opening state is illustrated.

Under state shown in Figure 1, because when the 2nd operation port 26 was supplied with propellant, propellant flowed in the cylinder chamber 28 the 2nd, and discharges gas from cylinder chamber 27 the 1st, thereby piston portion 22 just rises towards the drawing upside of Fig. 1.

At this moment, the 2nd piston lower surface 46d that contacts with surface of contact 21d in the cylinder barrel promotes under the gas pressure of propellant, the 2nd piston 46 as shown in Figure 2, move to cylinder barrel end surface of contact 21e with till valve body surface of contact 24d contacts.

And simultaneously, owing to contact with the recess surface of contact 46e of the 2nd piston 46 and the end surface of contact 45d of the 1st piston 45, the 1st piston 45 just together moves with the 2nd piston 46.

Thus, become the state of Fig. 2, the valve body 24 that is connected with the 1st piston 45 by movable axis 23 portion 34 that lifts off a seat, because of the 1st port 32 and the 2nd port 33 are communicated with, vacuum valve 1 becomes opening state.

Like this, because vacuum valve 1 becomes opening state, if for example the 1st port 32 is connected with not shown vacuum chamber, but the 2nd port 33 is connected with not shown vacuum pump, then passes through vacuum pump, the fluid in the vacuum chamber can be discharged.

The situation that vacuum valve 1 is in closed condition is illustrated.

Under state shown in Figure 2, owing in case, just in cylinder chamber 27 the 1st, flow into propellant, and from cylinder chamber 28 the 2nd, discharge gas, thereby piston portion 22 just descends towards the drawing downside of Fig. 2 to the 1st operation port 25 supply propellantes.

The propellant that flows in the cylinder chamber 27 the 1st pushes the 1st piston upper surface, makes the 1st piston 45 side shifting under drawing.

In addition, owing to be provided with fluid by hole 45c on the 1st piston 45, the propellant that flows in the cylinder chamber 27 the 1st pushes the 2nd piston upper surface 46g too, and the 2nd piston 46 also produces the power towards the drawing downside.

In addition, because of passing through hole 45c by fluid, pressure fluid also flows into lower surface, enough big as fluid by the size in the hole of hole 45c, then the compression area of the 1st piston 45 is not the sectional area of the 1st piston upper surface 45e, but with form the 2nd piston 46 on the sectional area of cylinder of the recess slip surface 46c that is provided with equate.Therefore, the compression area sum of the 1st piston 45 and the 2nd piston 46 equates with the sectional area of the cylinder that forms the interior surface of contact 21d of cylinder barrel.

Like this, piston 22 side shifting under drawing.

At this moment, the pressure of the position of the 1st piston 45 and the 2nd piston 46 relation resistance when flexible, the propellant supplied with to the 1st operation port 25 or the 2nd operation port 26 by the slip resistance of the 1st sliding mats 45a and the 2nd sliding mats 46a, metal bellows 36 or the balance of delivery volume are determined.

Therefore, surface of contact 21d time of contact in the 1st piston 45 and the cylinder barrel, and moment of contacting with the end surface of contact 45d of the 1st piston 45 of the 2nd piston 46 are also determined by above-mentioned balance.

For example, the recess surface of contact 46e of the 2nd piston 46 sets under the situation of contact before the 2nd piston lower surface 46d contacts with surface of contact 21d in the cylinder barrel with the end surface of contact 45d of the 1st piston 45, the result that propellant is supplied with to cylinder chamber 27 the 1st from the 1st operation port 25, the recess surface of contact 46e of the 2nd piston 46 contacted with the end surface of contact 45d of the 1st piston 45 before this, afterwards, contact with surface of contact 21d in the cylinder barrel by the 2nd piston lower surface 46d, the end surface of contact 45d of the recess surface of contact 46e of the 2nd piston 46 and the 1st piston 45 leaves.

At this moment, the 2nd piston lower surface 46d by the 2nd piston 46 contacts with surface of contact 21d in the cylinder barrel, because the 2nd piston 46 is side shifting under drawing again, just the 1st piston 45 will pass to valve body 24 towards the power of drawing downside, the sealed member 35 and seat portion 34 time of contact that possess at valve body 24, only under the pushing force effect of the 1st piston 45, sealed member 35 is crushed.

In addition, under the recess surface of contact 46e that surface of contact 21d sets at the 2nd piston 46 in the 2nd piston lower surface 46d and the cylinder barrel and the situation about contacting before the end surface of contact 45d of the 1st piston 45 contacts, the result that propellant is supplied with to cylinder chamber 27 the 1st from the 1st operation port 25, the 2nd piston lower surface 46d contacted with surface of contact 21d in the cylinder barrel before this, afterwards, the 1st piston 45 moves with the direction that the end surface of contact 45d of the 1st piston 45 contacts towards the recess surface of contact 46e of the 2nd piston 46.

At this moment, also the 2nd piston lower surface 46d by the 2nd piston 46 contacts with surface of contact 21d in the cylinder barrel, because the 2nd piston 46 is side shifting under drawing again, just the 1st piston 45 will pass to valve body 24 towards the power of drawing downside, the sealed member 35 and seat portion 34 time of contact that possess at valve body 24, only under the pushing force effect of the 1st piston 45, sealed member 35 is crushed.

Like this, under above-mentioned any situation, under sealed member 35 and seat portion 34 state of contact, just the pushing force from the 1st piston 45 is applied on the sealed member 35.

Fig. 3 and Fig. 4 show the 2nd piston lower surface 46d and contact with surface of contact 21d in the cylinder barrel, and then the view of direction from the end surface of contact 45d of the 1st piston 45 to the recess surface of contact 46e of the 2nd piston 46 that contact with of the 1st piston 45 when moving.

At first, as above-mentioned, supply with to cylinder chamber 27 the 1st from the propellant that the 1st operation port 25 is supplied with, as shown in Figure 3, the 2nd piston lower surface 46d of the 2nd piston 46 contacts with surface of contact 21d in the cylinder barrel.

At this moment, because the propellant of supplying with to cylinder chamber 27 the 1st passes through the fluid of the 1st piston 45 by hole 45c, and on the 2nd piston upper surface 46g of the 2nd piston 46, exert pressure, thereby then push surface of contact 21d in the cylinder barrel, but, power can not passed to the stepped part 23a of movable axis 23 from the joining portion 46f of the 2nd piston 46 because the 2nd piston 46 is in mobile lower limit.

On the other hand, the 1st piston 45 because of not being in mobile lower limit, and then is accepted the power that propellant is supplied with cylinder chamber 27 the 1st under Fig. 3 state, and under drawing side shifting.

Moving down of the 1st piston 45 is limited to state as described below: the sealed member 35 that is possessed at the valve body 24 that is connected with the 1st piston 45 by movable axis 23 contacts with seat portion 34, and the state with suitable decrement, the pass of promptly shown in Figure 5, stepped part 23a and joining portion 46f is to have the 1st space X ₁With the 2nd space X ₂State.

Under this state, by supplying with propellant to cylinder chamber 27 the 1st, the thrust and the sealed member 35 that give the 1st piston 45 have suitable decrement and flatten the counter-force balance that is produced, and can not use excessive power on sealed member 35.

That is, under vacuum valve 1 closing state, the 2nd piston 46 is in mobile lower limit, owing to have the 1st space X ₁With the 2nd space X ₂, can not transmit thrust to movable axis 23, only 45 pairs of sealed members 35 of the 1st piston apply pushing force.

The compression area from the pressure of propellant of the 1st piston 45 has fluid by hole 45c because of the 1st piston 45, therefore equates with the sectional area of the recess slip surface 46c of the 2nd piston 46.Therefore, the compression area of the 1st piston 45 is less than the sectional area of the cylinder inner face 21a of cylinder barrel 21, thereby imposes on the pushing force that the pushing force of sealed member 35 produces on can the whole sectional area less than the cylinder inner face 21a of cylinder barrel 21.

Like this, because vacuum valve 1 becomes closed condition, the 1st port 32 and the 2nd port 33 are cut off, if for example the 1st port 32 is connected with not shown vacuum chamber, and the 2nd port 33 is connected with not shown vacuum pump, then stops the discharge of the air in the vacuum chamber due to the vacuum pump.

As above-mentioned, when vacuum valve 1 was in closed condition, just the thrust that is produced by the 1st piston 45 was flattened the sealed member 35 that possesses in the valve body 24, available appropriateness defeat flat sealed member 35.

Therefore, do not use the excessive means of press seals parts 35 of trying hard to recommend, and then can prolong the life-span of sealed member 35.

When opening and closing vacuum valve 1 repeatedly, sealed member 35 just is pushed to seat portion 34 and deforms, but with the excessive force pushing, can make sealed member 35 deteriorations, shortens the life-span.

Thus, the user will often carry out the operations such as replacing of sealed member 35, but the vacuum valve of the application of the invention can reduce the loads such as pushing force that sealed member 35 is applied, owing to prolonged the life-span, can reduce the replacing frequency, can alleviate operator's burden.

In addition, press to the racking of sealed member 35 because by the operation of the compression area of the 1st piston 45 and propellant and to determine, be subjected to the influence of parts raw material intensity or size deviation hardly.The compression area of the 1st piston 45 is determined according to design.Therefore, assembling is during vacuum valve 1, the adjustment of being considered under need not patent documentation 1 situation.That is, can reduce cost when producing.

The 1st embodiment according to above-mentioned vacuum valve of the present invention 1 can have following effect.

(1) vacuum valve 1 has and is connected with valve body 31 and inner cylinder body portion 12 with movable axis 23, be formed at the 1st port 32 on the valve body 31, be formed on the valve body 31 and the 2nd port 33 that is communicated with the 1st port 32, the seat portion 34 that on the stream that is communicated with the 1st port 32 and the 2nd port 33, forms, be connected and have the valve body 24 of the sealed member 35 that contacts and leave with seat portion 34 with movable axis 23, it is characterized in that, cylinder body portion 12 have combine with movable axis 23 and compression area less than the 1st piston 45 of the cylinder inner face sectional area of cylinder body portion 12, with the 2nd piston 46 that engages with movable axis 23 and pressure by pressure fluid makes the 1st piston 45 move indirectly, by the 1st operation port 25 supply pressure fluids that on cylinder barrel 21, possess, the 1st piston 45 and the 2nd piston 46 pressurizeds, slide on the recess slip surface 46c of the 2nd piston 46 that the 1st piston 45 possesses in the 2nd piston 46 inside, the 2nd piston 46 slides on the cylinder inner face 21a of cylinder barrel 21, the 1st piston 45 and the 2nd piston 46 move thus, when the 2nd piston 46 contact with surface of contact 21d in the cylinder barrel that the 1st port 32 and the 2nd port 33 is cut off a side, owing between the 1st piston 45 and recess surface of contact 46e, have the 1st space X with the 2nd piston 46 of the 1st port 32 and the 2nd port 33 partitions one side ₁And then the 1st piston 45 towards the 1st port 32 and the 2nd port 33 are cut off a side shifting, only the pushing force of the 1st piston 45 becomes the racking that the sealed member that contacts seat portion 34 is applied, the 1st port 32 and the 2nd port 33 are cut off, thereby have when the opening of valves of vacuum valve 1 and valve when closing under the both of these case, can make the superior effect of the load range optimization that valve body is applied.

When opening of valves and valve when closing under the both of these case, the effect of the load range optimization that valve body 24 is applied realizes by following effect.

When the opening of valves of vacuum valve 1,, therefore press P by the operation of pressure fluid owing to undertaken by the 1st piston 45 and the 2nd piston 46 ₁Compression area A with the external diameter difference of the internal diameter of cylinder barrel 21 and movable axis 23 ₂Long-pending A ₂P ₁Determine.

On the other hand, when the valve of vacuum valve cut out, the sealed member that the 2nd piston 46 possesses on valve body 24 contacted with surface of contact 21d in the cylinder barrel with before seat portion 34 contacts, at the compression area A of 1st piston 45 littler than the sectional area of the cylinder inner face 21a of cylinder barrel 21 ₁Press P with operation ₁Long-pending A ₁P ₁Pushing force under, apply racking towards the sealed member 35 that contacts with seat portion 34, thereby the pushing that can carry out in the optimum load range sealed member 35.

Thus, when the opening of valves of vacuum valve 1, can be set in the optimum load range of pressure that overcomes the fluid in the inflow valve body 31, when valve cuts out with open valve, can be set in the decrement of sealed member 35 can only optimum load range in, can prolong life-span of sealed member 35.

In addition, the pushing force of the sealed member 35 that possesses on the valve body 24 is determined by the compression area of the 1st piston 45, thereby can be determined the unnecessary adjustment when need not to assemble by processing in advance.Therefore, also be effective subduing aspect the cost.

That is,, when opening of valves and valve when closing under the both of these case, the load range optimization that is applied on the valve body simultaneously, can be had the superior effect that the life-span is long, cost is low according to the invention of (1).

Therefore, because the internal diameter that does not dwindle cylinder barrel 21 just can realize alleviating the burden to sealed member 35, thereby needn't improve the pressure of propellant.

In addition,, the maintenance frequency of vacuum valve 1 can be reduced, user's burden can be alleviated by improving the life-span of the sealed member 35 that possesses on the valve body 24.

In addition, by adopting simple structure, the long lifetime that just can realize sealed member 35, can subdue manufacture cost with piston in combination.

(2) in the vacuum valve of (1) record, owing to it is characterized in that, the 1st piston 45 has the support that slides with the cylinder inner face 21a of cylinder body portion 12, the support of the 1st piston 45 is in the 1st operation port 25 sides, on the support of the 1st piston 45, have and make pressure fluid pass through the fluid of usefulness by hole 45c, thereby when valve body 24 is contacted with seat portion 34, can suppress movable axis 23, can apply impartial power and valve body 24 is contacted with seat portion 34 towards the waving of radial direction.

In addition, the compression area of the 1st piston 45 by fluid being set by hole 45c on the 1st piston 45, is compared with the sectional area of the cylinder inner face 21a of cylinder barrel 21, can reduce compression area.

(3) in the vacuum valve of (2) record, owing to it is characterized in that, the 2nd piston is passed by movable axis 23, between the 1st piston 45 and valve body 24, on movable axis 23, has the stepped part 23a that engages usefulness with the 2nd piston 46, the joining portion 46f of the 2nd piston 46 engages with stepped part 23a, the thickness of the joining portion 46f of the 2nd piston 46 is than little to the length of stepped part 23a from the end surface of contact 45d of the 1st piston 45, therefore, just can be with simple method at the 2nd piston 46 with after surface of contact 21d in the cylinder barrel contacts, amplitude with the action of the 1st piston 45 only produces the power that the sealed member 35 that possesses on the valve body 24 is contacted with seat portion 34 by the 1st piston 45.

(the 2nd embodiment)

Below, the 2nd embodiment of the present invention is described with reference to the accompanying drawings.At first the formation to the 2nd embodiment describes.

Fig. 7 shows the sectional view of the amplification under the 2nd embodiment's the closed condition of vacuum valve.

The 2nd embodiment is owing to be the 1st embodiment's variation, most ofly constitutes identically with the 1st embodiment, and the 2nd embodiment and the 1st embodiment's difference are structure different of piston portion 22 parts.Therefore, describe constituting different piston portion 22.Because of other parts are identical, omit its explanation.In Fig. 7, also the characteristic different with the 1st embodiment's formation illustrated enlargedly.

Piston portion 22 is made of the 1st piston 45 and the 2nd piston 46 these two pistons.

The 1st piston 45 is by being connected with the 2nd piston 46 as the diaphragm 47 of flexible film one example, and diameter is littler than the recess on the 2nd piston 46, is arranged to enter the state of the recess of the 2nd piston 46.In addition, the 1st piston 45 is connected with movable axis 23.

On the other hand, the 2nd piston 46 has the 2nd sliding mats 46a that can slide on the cylinder inner face 21a of cylinder barrel 21.And the 2nd piston can make movable axis 23 connect, and is arranged between the 1st piston 45 and the interior surface of contact 21d of cylinder barrel.Movable axis 23 is provided with stepped part 23a, and the joining portion 46f of the 2nd piston 46 is with by the end surface of contact 45d of the 1st piston 45 and the form of stepped part 23a clamping, engages with one section the part of attenuating of movable axis 23.

The thickness of joining portion 46f is littler than the distance of the end surface of contact 45d of the 1st piston and stepped part 23a, the 2nd piston 46 as shown in Figure 7, in the 2nd piston 46 and cylinder barrel under the surface of contact 21d state of contact, have and see from drawing and to make the 1st piston 45 space of knee-action only.

Below, the 2nd embodiment's of above-mentioned formation effect is described.

In addition, effect also is roughly the same with the 1st embodiment, for this describes differentiated closed condition.

In case supply with propellant to the 1st operation port 25, then propellant just flows in the cylinder chamber 27 the 1st, owing to discharge gases from cylinder chamber 28 the 2nd, thereby descend similarly with the 1st embodiment's the piston portion 22 drawing downside towards Fig. 2, the 2nd embodiment's piston portion 22 also descends.

And, as shown in Figure 7, in case the 2nd piston 46 contacts with surface of contact 21d in the cylinder barrel, even the pressure from propellant is applied to the 2nd piston upper surface 46g, because the 2nd piston 46 is in mobile lower limit, also can not pass to the stepped part 23a of movable axis 23 from the power of the joining portion 46f of the 2nd piston 46.

On the other hand, the 1st piston 45 is not because of being in mobile lower limit under Fig. 7 state, and then accepts the power of the propellant supplied with to cylinder chamber 27 the 1st, and under drawing side shifting.Because of the 1st piston 45 is connected with the 2nd piston 46 by diaphragm 47, from not being provided with slide part on one's body, can under than the little resistance of the 1st embodiment, move for the 1st piston 45.

Be limited under the moving of the 1st piston 45, by movable axis 23 with valve body 24 that the 1st piston 45 is connected on the sealed member 35 that possesses contact with seat portion 34, and have the state of suitable decrement.

Under this state, by supplying with propellantes, give the thrust of the 1st piston 45 and sealed member 35 and have suitable decrement and flatten the counter-force that is produced and balance each other to cylinder chamber 27 the 1st, on sealed member 35, can not act on excessive power.

That is, under the closed condition of vacuum valve 1, the 2nd piston 46 is in mobile lower limit, and thrust can not pass to movable axis 23, and only the 1st piston 45 is applied to pushing force on the sealed member 35.

The compression area from the pressure of propellant of the 1st piston 45 because the 1st piston 45 has fluid by hole 45c, thereby equates with the sectional area of the recess 46h of the 2nd piston 46.Therefore, the compression area of the 1st piston 45 is less than the sectional area of the cylinder inner face 21a of cylinder barrel 21, thereby is applied to the pushing force that pushing force on the sealed member 35 produces on can the whole sectional area less than the cylinder inner face 21a of cylinder barrel 21.

Like this, because of vacuum valve 1 is in closed condition, the 1st port 32 and the 2nd port 33 cut off, if for example the 1st port 32 is connected with not shown vacuum chamber, and the 2nd port 33 is connected with not shown vacuum pump, then stops the air discharging in the vacuum chamber due to the vacuum pump.

As above-mentioned, when vacuum valve 1 was in closed condition, only the thrust that is produced by the 1st piston 45 was flattened the sealed member 35 that possesses on the valve body 24, can be with the flat sealed member 35 of defeating of appropriateness.

Therefore, have and do not use the excessive means of press seals parts 35 of trying hard to recommend, can prolong the effect same in life-span etc. of sealed member 35 with the 1st embodiment.

As the advantage of using diaphragm 47 be,, therefore promptly use more weak trying hard to recommend when pressing the 1st piston 45, also power can be passed to movable axis 23 because of the recuperability that only adopts diaphragm 47 without frictional force just can be connected with the 2nd piston 46.

The support of the wear ring 45b that the 1st embodiment's the 1st piston 45 had can be set on the 1st piston 45 in addition.Can suppress waving of movable axis 23 by this support.

As above-mentioned, the 2nd embodiment by vacuum valve 1 of the present invention can obtain following effect.

(1) this vacuum valve 1 has and is connected with valve body 31 and the inner cylinder body portion 12 that is provided with movable axis 23, be formed at the 1st port 32 on the valve body 31, be formed on the valve body 31 and the 2nd port 33 that is communicated with the 1st port 32, the seat portion 34 that on the stream that is communicated with the 1st port 32 and the 2nd port 33, forms, be connected and have the valve body 24 of the sealed member 35 that contacts and leave with seat portion 34 with movable axis 23, it is characterized in that, cylinder body portion 12 have engage with movable axis 23 and compression area less than the 1st piston 45 of the cylinder inner face sectional area of cylinder body portion 12, with the 2nd piston 46 that engages with movable axis 23 and pressure by pressure fluid makes the 1st piston 45 move indirectly, the 1st piston 45 is in the inboard of the 2nd piston 46, the periphery of the 1st piston 45 was connected by diaphragm 47 with the interior week of the 2nd piston 46, by the 1st operation port 25 supply pressure fluids that in cylinder body portion 12, possess, the 1st piston 45 and the 2nd piston 46 pressurizeds move, when the 2nd piston 46 contact with surface of contact 21d in the cylinder barrel that the 1st port 32 and the 2nd port 33 is cut off a side, owing between the 1st piston 45 and recess surface of contact 46e, have the 1st space X with the 2nd piston 46 of the 1st port 32 and the 2nd port 33 partitions one side ₁Thereby the 1st piston 45 towards the 1st port 32 and the 2nd port 33 are cut off a side shifting, only the pushing force of the 1st piston 45 becomes the racking that the sealed member 35 that contacts seat portion 34 is applied, the 1st port 32 and the 2nd port 33 are cut off, make 45 actions of the 1st piston owing to fricton-tight by diaphragm 47, thereby outside the effect that obtains equating, can under than the little resistance of the 1st embodiment's vacuum valve, make 45 actions of the 1st piston with the 1st embodiment's vacuum valve.

In addition, the compression area of the 1st piston 45, by on the 1st piston 45, being provided with vent, can be less than the cylinder inner face sectional area of cylinder barrel 21.

(3) in the vacuum valve of (2) record, owing to it is characterized in that, the 2nd piston 46 is passed by movable axis 23, and between the 1st piston 45 and valve body 24, on movable axis 23, has the stepped part 23a that engages usefulness with the 2nd piston 46, the joining portion 46f of the 2nd piston 46 engages with stepped part 23a, the thickness of the joining portion 46f of the 2nd piston 46 is than little to the length of stepped part 23a from the end surface of contact 45d of the 1st piston 45, therefore, just can be with simple method at the 2nd piston 46 with after surface of contact 21d in the cylinder barrel contacts, obtain the amplitude of the 1st piston 45 action, only produce the power that the sealed member 35 that possesses on the valve body 24 is contacted with seat portion 34 by the 1st piston 45.

(the 3rd embodiment)

Below, the 3rd embodiment of the present invention is described with reference to the accompanying drawings.At first the formation to the 3rd embodiment describes.

Fig. 8 shows the sectional view of the amplification under the 3rd embodiment's the closed condition of vacuum valve.

The 3rd embodiment is owing to be the 1st embodiment's variation, most ofly constitutes identically with the 2nd embodiment with the 1st embodiment, and the 3rd embodiment and the 1st embodiment and the 2nd embodiment's difference are structure different of piston portion 22 parts.Therefore, describe constituting different piston portion 22.Because of other parts are identical, omit its explanation.In Fig. 8, also the characteristic different with the 1st embodiment's formation illustrated enlargedly.

The 1st piston 45 is provided with the recess that the protuberance on the 2nd piston 46 is embedded, and the 1st piston 45 is connected with movable axis 23.In addition, between the protuberance of the recess of the 1st piston 45 and the 2nd piston 46, slidably the 1st sliding mats 45a is arranged at the 1st piston 45 sides.

On the other hand, the 2nd piston 46 has the 2nd sliding mats 46a that can slide on the cylinder inner face 21a of cylinder barrel 21.And the 2nd piston can make movable axis 23 connect, and is arranged between the 1st piston 45 and the interior surface of contact 21d of cylinder barrel.Movable axis 23 is provided with stepped part 23a, and the joining portion 46f of the 2nd piston 46 is with by the recess interior edge face 45f of the 1st piston 45 and the form of stepped part 23a clamping, engages with one section the part of attenuating of movable axis 23.

The thickness of joining portion 46f is than little to the distance of stepped part 23a from the recess interior edge face 45f of the 1st piston.

In addition, the recess interior edge face 45f of the 1st piston 45 is with before protuberance end face 46i contacts, and end surface of contact 45d makes a concession to not contacting with the 2nd piston upper surface 46g.

That is, the distance from recess interior edge face 45f to protuberance end face 46i is being made as the 1st space X ₁, be made as the 3rd space X from the distance of end surface of contact 45d to the 2 piston upper surface 46g ₃The time, become the 1st space X ₁＜the 3 space X ₃Relation.

Thus, the 2nd piston 46, has from drawing and sees the 1st piston 45 space of knee-action only under the surface of contact 21d state of contact as illustrated in fig. 8, in the 2nd piston 46 and the cylinder barrel.

In addition, with the 1st space X ₁With the 3rd space X ₃Which distance shortens, owing to belong to the design item, can suitably change according to the face of wanting to contact.

Below, the 3rd embodiment's of above-mentioned formation effect is described.

Effect also is roughly the same with the 1st embodiment and the 2nd embodiment, for this describes differentiated closed condition.

In case supply with propellant to the 1st operation port 25, then propellant just flows in the cylinder chamber 27 the 1st, owing to discharge gases from cylinder chamber 28 the 2nd, just with the 1st embodiment's piston portion 22 towards the drawing downside decline of Fig. 2 similarly, the 3rd embodiment's piston portion 22 also descends.

And, as shown in Figure 8, in case the 2nd piston 46 contacts with surface of contact 21d in the cylinder barrel, even the pressure from propellant is applied to the 2nd piston upper surface 46g, because the 2nd piston 46 is in mobile lower limit, also can power not passed to the stepped part 23a of movable axis 23 from the joining portion 46f of the 2nd piston 46.

On the other hand, the 1st piston 45 is not because of being in mobile lower limit under Fig. 8 state, thereby further accepts the power of the propellant supplied with to cylinder chamber 27 the 1st, and under drawing side shifting.The protuberance of the 1st piston 45 and the 2nd piston 46 slides, and under drawing side shifting.

Under this state, by supplying with propellantes, give the thrust of the 1st piston 45 and sealed member 35 and have suitable decrement and flatten the counter-force that is produced and balance each other to cylinder chamber 27 the 1st, on sealed member 35, can not use excessive power.

The compression area from the pressure of propellant of the 1st piston 45 has fluid by hole 45c because of the 1st piston 45, and equates with the sectional area of the protuberance end face 46i of the 2nd piston 46.Therefore, the compression area of the 1st piston 45 is less than the sectional area of the cylinder inner face 21a of cylinder barrel 21, thereby is applied to the pushing force that pushing force on the sealed member 35 produces on can the whole sectional area less than the cylinder inner face 21a of cylinder barrel 21.

Like this, because of vacuum valve 1 is in closed condition, the 1st port 32 and the 2nd port 33 cut off, if for example the 1st port 32 is connected with not shown vacuum chamber, and the 2nd port 33 is connected with not shown vacuum pump, stop then that the interior air of vacuum chamber discharges due to the vacuum pump.

For the 3rd embodiment and the 1st embodiment, the 1st piston 45 is opposite with the concavo-convex relationship of the 2nd piston 46, even but under such formation situation, also can obtain same effect.

The support of the wear ring 45b that the 1st embodiment's the 1st piston 45 had can be set on the 1st piston 45.Can suppress waving of movable axis 23 by this support.

As above-mentioned, the 3rd embodiment by vacuum valve 1 of the present invention can obtain following effect.

(1) vacuum valve 1 has and is connected with valve body 31 and inner cylinder body portion 12 with movable axis 23, be formed at the 1st port 32 on the valve body 31, be formed on the valve body 31 and the 2nd port 33 that is communicated with the 1st port 32, the seat portion 34 that on the stream that is communicated with the 1st port 32 and the 2nd port 33, forms, be connected and have the valve body 24 of the sealed member 35 that contacts and leave with seat portion 34 with movable axis 23, it is characterized in that, cylinder body portion 12 have engage with movable axis 23 and compression area less than the 1st piston 45 of the cylinder inner face sectional area of cylinder body portion 12, with the 2nd piston 46 that engages with movable axis 23 and pressure by pressure fluid makes the 1st piston 45 move indirectly, by the 1st operation port 25 supply pressure fluids that on cylinder barrel 21, possess, the 1st piston 45 and the 2nd piston 46 pressurizeds, the 1st piston 45 slides on the protuberance wall that the 2nd piston 46 is possessed, the 2nd piston 46 slides on the cylinder inner face 21a of cylinder barrel 21, the 1st piston 45 and the 2nd piston 46 move thus, when the 2nd piston 46 contact with surface of contact 21d in the cylinder barrel that the 1st port 32 and the 2nd port 33 is cut off a side, because the 1st piston 45 has the 1st space X between with the protuberance end face 46i of the 1st port 32 and the 2nd port 33 partitions one side and the 2nd piston upper surface 46g ₁With the 3rd space X ₃The 1st piston 45 and then towards the 1st port 32 and the 2nd port 33 are cut off a side shifting, only the pushing force of the 1st piston 45 becomes the racking that the sealed member 35 that contacts seat portion 34 is applied, the 1st port 32 and the 2nd port 33 are cut off, thereby can obtain the effect that equates with the 1st embodiment's vacuum valve.

(2) in the vacuum valve of (1) record, it is characterized in that, the 1st piston 45 has the support that slides with the cylinder inner face 21a of cylinder body portion 12, the support of the 1st piston 45 is in the 1st operation port 25 sides, on the support of the 1st piston 45, have and make pressure fluid pass through the fluid of usefulness by hole 45c, thereby when valve body 24 is contacted with seat portion 34, can suppress movable axis 23, can apply impartial power and valve body 24 is contacted with seat portion 34 towards the waving of radial direction.

In addition, the compression area of the 1st piston 45, by on the 1st piston 45, being provided with vent, can be less than the cylinder inner face sectional area of cylinder barrel.

(3) in the vacuum valve of (2) record, it is characterized in that, the 2nd piston 46 is passed by movable axis 23, and between the 1st piston 45 and valve body 24, on movable axis 23, has the stepped part 23a that engages usefulness with the 2nd piston 46, the joining portion 46f of the 2nd piston 46 engages with stepped part 23a, the thickness of the joining portion 46f of the 2nd piston 46 is than little to the length of stepped part 23a from the recess interior edge face 45f of the 1st piston 45, therefore, just can be with simple method at the 2nd piston 46 with after surface of contact 21d in the cylinder barrel contacts, obtain the amplitude of the 1st piston 45 action, only just produce the power that the sealed member 35 that possesses on the valve body 24 is contacted with seat portion 34 by the 1st piston 45.

(the 4th embodiment)

Below, the 4th embodiment of the present invention is described with reference to the accompanying drawings.At first the formation to the 4th embodiment describes.

Fig. 9 shows the sectional view of the amplification under the 4th embodiment's the closed condition of vacuum valve.

The 4th embodiment is owing to be the 1st embodiment's variation, most ofly constitutes identically with the 1st embodiment, is structure different of piston portion 22 parts with the 1st embodiment's difference.Therefore, describe constituting different piston portion 22.Because of other parts are identical, omit its explanation.In Fig. 9, also the characteristic different with the 1st embodiment's formation illustrated enlargedly.

The 1st piston 45 is provided with the 2nd piston 46 and enters the recess of usefulness, and the 1st piston 45 is connected with movable axis 23.And, on the 2nd piston 46, be provided with at recess and prevent that the 1st piston 45 from extracting the retainer 46j of usefulness.

On the other hand, the 2nd piston 46 has the 2nd sliding mats 46a that can slide at the cylinder inner face 21a of cylinder barrel 21.And the 2nd piston connects movable axis 23, and is arranged between the 1st piston 45 and the interior surface of contact 21d of cylinder barrel.

The thickness of the 1st piston 45 is littler than the distance from retainer 46j to recess surface of contact 46e.Therefore, the 2nd piston 46 under the surface of contact 21d state of contact, has from drawing and sees the 1st piston 45 space of knee-action only in the 2nd piston 46 and cylinder barrel as shown in Figure 9.

Different with the 1st embodiment, in the 4th embodiment, the shape of the 1st piston 45 is not for having the shape of the support of being with wear ring 46b.Therefore, need reduce the gap of movable axis 23 and movable axis holding part 21b, become the formation that rectification is axially waved.

Below, the 4th embodiment's of above-mentioned formation effect is described.

Effect also is roughly the same with the 1st embodiment, therefore only differentiated closed condition is described.

In case supply with propellantes to the 1st operation port 25, then propellant just flows in the cylinder chamber 27 the 1st, to discharge gases from cylinder chamber 28 the 2nd, thereby descend similarly with the 1st embodiment's piston portion 22 drawing downside towards Fig. 2, the 4th embodiment's piston portion 22 also descends.

And, as shown in Figure 9, in case the 2nd piston 46 contacts with surface of contact 21d in the cylinder barrel, even the pressure from propellant is applied to the 2nd piston upper surface 46g, because the 2nd piston 46 is in mobile lower limit, power can not passed to the 1st piston 45 that combines with movable axis 23 from the retainer 46j of the 2nd piston 46 yet.

On the other hand, the 1st piston 45 is not because of being in mobile lower limit under Fig. 9 state, further accepts the power of the propellant supplied with to cylinder chamber 27 the 1st, and under drawing side shifting.The recess of the 1st piston 45 and the 2nd piston 46 slides, and under drawing side shifting.

Be limited under the moving of the 1st piston 45, the sealed member 35 that the valve body 24 that is connected with the 1st piston 45 by movable axis 23 is possessed contacts with seat portion 34, and has the state of suitable decrement.

Under this state, by supplying with the thrust that propellantes give the 1st piston 45, have suitable decrement with sealed member 35 and flatten the counter-force that is produced and balance each other to cylinder chamber 27 the 1st, on sealed member 35, can not use excessive power.

The compression area from the pressure of propellant of the 1st piston 45 equates with the sectional area of the recess slip surface 46c of the 2nd piston 46.Therefore, the compression area of the 1st piston 45 is less than the sectional area of the cylinder inner face 21a of cylinder barrel 21, thereby is applied to the pushing force that pushing force on the sealed member 35 produces on can the whole sectional area less than the cylinder inner face 21a of cylinder barrel 21.

As above-mentioned, the 4th embodiment by vacuum valve 1 of the present invention can obtain following effect.

(1) vacuum valve 1 has and is connected with valve body 31 and inner cylinder body portion 12 with movable axis 23, be formed at the 1st port 32 on the valve body 31, be formed on the valve body 31 and the 2nd port 33 that is communicated with the 1st port 32, the seat portion 34 that on the stream that is communicated with the 1st port 32 and the 2nd port 33, forms, be connected and have the valve body 24 of the sealed member 35 that contacts and leave with seat portion 34 with movable axis 23, it is characterized in that, cylinder body portion 12 have engage with movable axis 23 and compression area less than the 1st piston 45 of the cylinder inner face sectional area of cylinder body portion 12, with the 2nd piston 46 that engages with movable axis 23 and pressure by pressure fluid makes the 1st piston 45 move indirectly, by the 1st operation port 25 supply pressure fluids that on cylinder barrel 21, possess, the 1st piston 45 and the 2nd piston 46 pressurizeds, slide on the recess slip surface 46c of the 2nd piston 46 that the 1st piston 45 possesses in the inside of the 2nd piston 46, the 2nd piston 46 slides on the cylinder inner face 21a of cylinder barrel 21, the 1st piston 45 and the 2nd piston 46 move thus, when the 2nd piston 46 contact with surface of contact 21d in the cylinder barrel that the 1st port 32 and the 2nd port 33 is cut off a side, owing to have the 1st space X between the 1st piston 45 and the recess surface of contact 46e with the 2nd piston 46 of the 1st port 32 and the 2nd port 33 partitions one side ₁Thereby the 1st piston 45 further towards the 1st port 32 and the 2nd port 33 are cut off a side shifting, only the pushing force of the 1st piston 45 becomes the racking that the sealed member 35 that contacts seat portion 34 is applied, the 1st port 32 and the 2nd port 33 are cut off, thus have can be when the opening of valves of vacuum valve 1 and valve make the effect that equates with the 1st embodiment of the load range optimization that is applied on the valve body etc. when closing under the both of these case.

(the 5th embodiment)

Below, the 5th embodiment of the present invention is described with reference to the accompanying drawings.At first the formation to the 5th embodiment describes.

Figure 10 shows the cross section enlarged view of the 5th embodiment's vacuum valve.The 1st piston is in the upper end of stroke.On the other hand, Figure 11 illustrates the enlarged view under the 5th embodiment's the opening state.The 1st piston is in the upper end of stroke.

The 5th embodiment has the formation roughly the same with the 1st embodiment, but difference is, in example shown in Figure 10, is provided with vent 46k on the 2nd piston 46.In example shown in Figure 11, the 2nd piston 46 is provided with retainer 46l.

Vent 46k and retainer 46l are arranged on the 2nd piston 46.The purpose that vent 46k and retainer 46l are set is, when surface of contact 21d contacts in the cylinder barrel that possesses on the 2nd piston lower surface 46d that possesses on the 2nd piston 46 and the cylinder barrel 21, makes and is close to and the vent ability of venting capability when descending assisted.

Surface of contact 21d is when good and flatness is high with the surface roughness of the 2nd piston lower surface 46d in the cylinder barrel, or when adhering to the lubricating grease etc. of lubricated usefulness, interior surface of contact 21d of cylinder barrel and the 2nd piston lower surface 46d may be close to.In case surface of contact 21d and the 2nd piston lower surface 46d are close in the cylinder barrel, as shown in Figure 5, then hinder the 1st gap X that generates between the 1st piston 45 and the 2nd piston 46 ₁The vent ability in the space of part can hinder the action of the 1st piston 45, for fear of such state of affairs, is provided with vent 46k and retainer 46l, helps the vent ability between the 1st piston 45 and the 2nd piston 46.

Vent 46k and retainer 46l can only be provided with 1 place in order fully to guarantee vent ability, also can be provided with a plurality of.

In addition, although embodiments of the invention are illustrated, the present invention is not limited to the foregoing description, can have various application.

For example, replaceable at the material shown in each position is other materials that suit.

On the other hand, be arranged at fluid on the 1st piston 45 by hole 45c because of being purpose by fluid, so, not only can be simple circular port, also can be the shape that on the 1st piston 45, is provided with otch.

And, the shape of the 1st port 32 and the 2nd port 33 also can become according to connecting object, these all are in the scope of design item, for example, also can consider the 1st port part 41 of the 1st port 32 and the 2nd port part 42 of the 2nd port 33 are spent the direction bendings towards 45.

On the other hand, the 1st sliding mats 45a that sets up for the 1st piston 45 relative the 2nd pistons 46 that make the 1st embodiment and the 3rd embodiment slide can be arranged at the 1st piston 45 sides, also can be arranged at the 2nd piston 46 sides.

Claims

1. vacuum valve, have and be connected with valve body and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that

Described cylinder body has and combines with described movable axis and compression area engages less than the 1st piston of the cylinder inner face sectional area of described cylinder body with described movable axis and the pressure by pressure fluid makes described the 1st piston move indirectly the 2nd piston,

Supply with described pressure fluid by the 1st operation port that on described cylinder body, possesses, described the 1st piston and described the 2nd piston pressurized, described the 1st piston slides on the recess inwall that described the 2nd internal piston is possessed, described the 2nd piston slides on the cylindrical part internal face of described cylinder body, described thus the 1st piston and described the 2nd piston move

When described the 2nd piston contacts with retainer with the 2nd piston that described the 1st port and described the 2nd port is cut off a side, cut off the 1st piston of a side with having the space between the retainer owing to described the 1st piston and with described the 1st port and described the 2nd port, thereby the 1st piston further towards described the 1st port and described the 2nd port are cut off a side shifting, the pushing force of only described the 1st piston becomes the racking that the described sealed member that contacts described valve seat is applied, and described the 1st port and described the 2nd port are cut off.

2. vacuum valve, have and be connected with valve body and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that

The 1st piston is in the inboard of described the 2nd piston, and the periphery of described the 1st piston is connected by flexible film in interior week with described the 2nd piston,

Supply with described pressure fluid by the 1st operation port that on described cylinder body, possesses, described the 1st piston and described the 2nd piston pressurized and move,

3. vacuum valve, have and be connected with valve body and inner cylinder body with movable axis, be formed at the 1st port on the described valve body, be formed on the described valve body and the 2nd port that is communicated with described the 1st port, the valve seat that on the stream that is communicated with described the 1st port and described the 2nd port, forms, be connected and have the valve body of the sealed member that contacts and leave with described seat portion with described movable axis, it is characterized in that

Supply with described pressure fluid by the 1st operation port that on described cylinder body, possesses, described the 1st piston and described the 2nd piston pressurized, described the 1st piston slides on the protuberance wall that possesses on described the 2nd piston, described the 2nd piston slides on the cylindrical part internal face of described cylinder body, described thus the 1st piston and described the 2nd piston move

4. according to the arbitrary described vacuum valve of claim 1～3, it is characterized in that, described the 1st piston has the support that the described cylindrical part internal face with described cylinder body slides, described support is in described the 1st operating end oral-lateral, has on the described support to make the vent of described pressure fluid by usefulness.

5. according to the arbitrary described vacuum valve of claim 1～3, it is characterized in that, described the 2nd piston is passed by described movable axis, and be located between described the 1st piston and the described valve body, on described movable axis, has the fastening portion that engages usefulness with described the 2nd piston, engage with the joining portion of described the 2nd piston, the thickness at the described joining portion of described the 2nd piston is littler than the length from described the 1st piston end face to described fastening portion.

6. according to the arbitrary described vacuum valve of claim 1～3, it is characterized in that, described the 1st piston has the support that the described cylindrical part internal face with described cylinder body slides, described support is in described the 1st operating end oral-lateral, has the vent of using by described pressure fluid on the described support, described the 2nd piston is passed by described movable axis, and be located between described the 1st piston and the described valve body, on described movable axis, has the fastening portion that engages usefulness with described the 2nd piston, engage with the joining portion of described the 2nd piston, the thickness at the described joining portion of described the 2nd piston is littler than the length from described the 1st piston end face to described fastening portion.