JPS63285373A - Diaphragm seal valve - Google Patents

Abstract

PURPOSE:To provide a valve not polluted by metal powder, sealed securely and having small flowing resistance by vertically moving a diaphragm sandwiched between a valve body and a lid relative to a valve seat to open and close the valve. CONSTITUTION:A main body 1 is formed with a inflow port 3, outflow port 4 and a valve seat(seat) 7. A thin metal plate diaphragm 9 is sealed and sandwiched between the main body 1 and a lid 2. The diaphragm 9 is mounted with the central portion bulging upward. A valve rod 8 screwed into the lid 2 is lowered to press the diaphragm 9 against the valve seat 7 and close a valve, and lifted to open the valve. Thus, a spring and the like are not on a passing fluid contact section in the valve and metal powder is not produced by wear. Also, since the valve is opened and closed by the valve rod 8 slightly eccentric to the valve seat 7, sealing is securely achieved and the upward bulging of diaphragm 9 provides small flowing resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a relatively small diameter diaphragm seal valve used in various gas industries, analysis, medicine, biotechnology, instrumentation, etc.

[Prior Art] Conventionally, metal diaphragm seal valves as shown in FIG. 5 have been used in these fields.

In FIG. 5, 151 is a main body, and 152 is a lid.

Valve body 15 with valve seat 153 installed in advance in main body 151
4 and the spring 155, and place the metal diaphragm 156 on top of the valve body.The lid 152 is provided on the top of the main body, but the valve stem 157 is screwed in in advance, and the main body 151 and the lid 152 are inserted.
Sandwich the diaphragm 156 between them and tighten. 15
8 is a manual handle for operating the valve, and 159 is a set screw for fixing the handle 158 to the valve stem 157. Leakage to the outside between the valve body and the lid and along the valve stem thread 160 is sealed by the diaphragm, so no leakage occurs.The valve body 154 is normally pushed up by the spring 155, and the valve is in the closed state. It is in. By operating the handle 158, the valve stem 15
7 descends while rotating. As a result, diaphragm 1
56 causes deflection and pushes down the valve body 154 against the spring 155, causing the valve seat 153 to move against the seat 161 of the main body.
to close the valve.

[Problems that the invention attempts to solve] The disadvantages of the above diaphragm seal valve are as follows.

Since the valve body and spring are installed inside the valve,
When the valve is opened and closed by flowing fluid, the inner wall of the main body, spring, valve body, and diaphragm cause contact wear with each other. Metal powder generated by this contact wear gets caught in the seat surface and causes seat leakage. This metal powder is absolutely unacceptable in piping where cleanliness is required, and since the valve body is not integrated with the valve stem but is separated, it tends to become eccentric when opening and closing the valve, and the valve seat and main body seat The contact surface is not fixed, and the impressions of the main body seat on the valve seat prevent leakage prevention.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an object of the present invention is to provide a valve that does not have a valve body and a spring inside the valve and can open and close the valve.

[Means for Solving the Problems] As described above, the present invention is a valve that eliminates the valve body and spring, and its characteristics are that the upper part is open, the outflow inlets are formed on the left and right sides, and the upwardly facing inlet is connected to the inflow port. A main body having a flow path, a lid attached to the upper part of the main body, a valve rod that penetrates the center part of the lid and is screwed at this penetrating part, and an outer peripheral part between the main body and the lid. The valve stem is lowered, and the diaphragm in contact with the valve stem is simultaneously lowered and pressed against the sheet at the end of the upward flow path of the main body, thereby making the valve a leapfrog, and the lowered diaphragm This is a diaphragm seal valve that opens the valve by raising the valve stem and raising the diaphragm by making the valve into an elastic deformation region.

[Embodiment] FIG. 1 shows an embodiment of the present invention, in which a diaphragm seal valve is in a fully open state.

1 is the main body of the diaphragm seal valve, which is constructed as follows. Forming an inlet 3 on the left side and an outlet 4 on the right side,
An upward flow path 5 that is connected to the inflow port and whose flow direction is upward is formed in the center, and a downward flow path 6 that is connected to the outflow port and whose flow direction is downward is further formed on the outlet side of the upward flow path 5.

In addition, a sheet 7 of synthetic resin or the like is provided at the upper end of the upward flow path 5.
Attach. The upper part of the main body of the valve is open, and a lid 2 is fitted onto the upper part of the main body 1, and a step 12 is formed at the fitting part of the main body 1 as a stopper for the fitted lid. By fitting and installing this lid 2, the upper part of the main body 1 and the lid 2
A fluid chamber 13 is formed between the body 1 and the lid 2, and this fluid chamber 13 connects the upward flow path 5 and the downward flow path 6. A thin plate diaphragm 9 is provided between the diaphragm 9 and the lower surface of the lid 2, and its outer periphery is held between the main body stepped portion 12 and the lower surface of the outer periphery of the lid 2.

This clamping is carried out by cutting a thread on the outer periphery of the upper part of the main body, and then screwing and tightening the lid holding nut 10 which is threaded into this external thread. By sandwiching the diaphragm 9 between the main body 1 and the lid 2, the fluid chamber 13 described above is separated by the diaphragm 9. A valve rod 8 passes through the center of the lid 2, and the lid 2 and the valve rod 8 are screwed together in this penetrating portion. This valve stem 8 is rotatable and rises and falls as it rotates.

A handle 11 is detachably fixed to the upper part of the valve stem 8, and by rotating the handle 11, the valve stem 8 moves up and down.The lowermost part of the valve stem 8 is in surface contact with the diaphragm 9, By rotating the handle 11 fixed to and lowering the valve stem 8, the diaphragm 9 is also pushed down at the same time.

The pushed down diaphragm 9 finally comes into contact with the seat 7 attached to the upper part of the upward flow path 5, and the valve becomes fully closed. Thereafter, when the valve stem 8 is raised by rotating the handle, the diaphragm 9 follows the valve stem and rises.

That is, in the present invention, the diaphragm 9 is deformed within the elastic range to open and close the valve.As described above, since there is no spring and valve body inside the valve, the diaphragm 9 is deformed within the elastic range, so the spring and the inner wall of the main body, and the spring and the valve body are separated. There is no contact wear. Therefore, no metal powder is generated due to contact wear.

The diaphragm 9 usually has a partially spherical shell shape with a large radius of curvature. The diaphragm 9 is configured so that when the diaphragm 9 is pushed down by the valve stem 8 to a fully closed state, and then the valve stem 8 is raised to open the valve, the diaphragm 9 follows the valve stem. The shape of will be explained.

FIG. 2 is a longitudinal sectional view of the diaphragm 9, which has a partial spherical shell shape with a large curvature. In FIG. 2, the radius of curvature of the diaphragm is R, the thickness of the diaphragm is t, and the angle formed by the straight line connecting the center of curvature of the diaphragm and both ends of the diaphragm is 2β.

The amount of deformation of the diaphragm when the diaphragm having this shape is pushed by the valve stem 8 with a load of Pkg is defined as δm. When the values of α expressed by the load P, the diaphragm plate thickness t, and the angle β are varied (when α is taken as a parameter), P and δ
The relationship is as shown in Figure 4. In Figure 4, when the value of load P is small, the diaphragm deformation is almost in the elastic range, so when the value of α is large, the amount of diaphragm deformation δ in the elastic deformation range is large, and therefore If α is set to a large value, the flow rate when the valve is fully open will be large, and the flow resistance will be small.

Here, the elastic range of the diaphragm 9 refers to the range in which the diaphragm also rises when the valve stem 8 is lifted after the diaphragm is pushed down and deformed by the valve stem 8.

Further, in this embodiment, a sheet 7 made of synthetic resin or the like is attached to the upper end of the upward flow path 5. However, the diaphragm 9 may be coated with a synthetic resin or the like, and the upper end portion of the upward flow path 5 may be formed into a protruding shape while the main body is made of metal.

The diaphragm seal valve according to this embodiment does not have a valve body or a spring inside the valve, so there is no frictional sliding part of these, and therefore no metal powder is generated due to friction. Furthermore, the valve can be opened and closed, and the flow resistance of the valve is small. Also, since there is no valve body, there is no eccentricity of the valve body.

[Effect of the invention] The effects of the present invention are as follows.

a. Since there is no friction sliding part in the contact part of the passing fluid inside the valve,
No metal powder is generated, and there is no sheet leakage or metal powder contamination of the piping system due to generated metal powder biting the seat surface.

b. Since the valve stem is equipped with an eccentricity prevention mechanism, there is no eccentricity of the valve body due to sudden opening and closing of the valve or turbulent flow of fluid, and reliable sealing performance is maintained for a long time.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of an embodiment of the present invention when the valve is open, Fig. 2 is a longitudinal sectional view of the diaphragm, Fig. 3 is a longitudinal sectional view of the diaphragm being pushed down by the valve stem, and Fig. 4. 5 is a diagram showing the relationship between the load applied to the diaphragm and the amount of deformation, and FIG. 5 is a longitudinal sectional view of a conventional diaphragm seal valve. 1...Body 2...Lid 7...Seat 8...Valve stem 9...Diaphragm agent Patent attorney Katsuhiko Ino Kuma l Item 2 Item 50 J9 H/ /≦7B procedure Written amendment (spontaneous) 1 Indication of the case 1988 Patent Application No. 92275 2
Title of the invention Diaphragm seal valve 3 Relationship to the person making the amendment Patent applicant address 2-1-2 Marunouchi, Chiyoda-ku, Tokyo Name (5)
0g") Hitachi Metals Co., Ltd. 4 Agent Address: 404-404-8-1, Kinuta, Setagaya-ku, Tokyo 5 "Claims" and "Detailed Description of the Invention" of the specification to be amended
column. 6. Details of the amendments are as shown in the attached sheet. 1. The "Claims" column of the specification is amended as follows. A diaphragm seal valve consisting of a thin sheet metal (1 diaphragm) whose peripheral edge is tightly held between the main body and the lid and whose middle part bulges upward, and when the valve stem is lowered, the diaphragm seal valve. 2. Specification No. Page 3, line 19, ``[Problem...J'' to page 9, line 5, ``Keep...'' is corrected as follows6 [Means for solving the problem] The present invention The main body has a recess communicating with the outflow port on the upper surface, and a valve seat communicating with the inflow port is formed in the center of the recess, a lid fixed to the upper part of the main body and having a through hole in the center; It consists of a valve stem that fits into a through hole in the lid so that it can be raised and lowered, and a thin metal diaphragm that has its periphery sealed between the main body and the lid and whose central part bulges upward. When the valve stem is raised, the diaphragm elastically deforms and presses against the valve seat to close the valve, and when the valve stem is raised, the diaphragm elastically returns to its original shape to open the valve. It is a diaphragm seal valve. [Example] An example of the present invention will be described with reference to the accompanying drawings.
The figure is a longitudinal sectional view showing the diaphragm seal valve of the same embodiment in a fully open state. 1 is the main body of the diaphragm seal valve, which is constructed as follows. Forming an inlet 3 on the left side and an outlet 4 on the right side,
An upward flow path 5 that connects to the inlet 3 and has an upward flow direction is formed in the center, and a downward flow path 6 that connects to the outlet 4 and has a downward flow direction is further formed on the outlet side of the upward flow path 5. . In addition, a sheet 7 of synthetic resin or the like is provided at the upper end of the upward flow path 5.
Attach and use it as a valve seat. The upper part of the main body of the valve is open, and a lid 2 is fitted and attached to the upper part of the main body 1, and a step 12 is formed at the fitting part of the main body 1 as a stopper for the fitted lid 2. A fluid chamber 13 is formed between the upper part of the main body 1 and the lid 2 by fitting and attaching them, and this fluid chamber 13 communicates the upward flow path 5 and the downward flow path 6. When the main body 1 and the lid 2 are fitted together, a thin metal diaphragm 9 with a center portion bulging upward is arranged above the seat 7 of the main body 1, and the peripheral edge of the diaphragm 9 is aligned with the step 12 of the main body. and the lower surface of the outer periphery of the lid 2 to hold the lid 2 in a sealed manner. To do this, cut a thread on the outer periphery of the top of the main body.
This is done by screwing and tightening the lid retainer nut lO which is screwed onto this male thread. The fluid chamber 13 described above is created by sandwiching the diaphragm 9 between the main body 1 and the lid 2.
is separated by this diaphragm 9. There is a through hole in the center of the lid 2 through which the valve rod 8 passes, and the lid 2 and the valve rod 8 are screwed together in this through hole. This valve stem 8 is rotatable, and a handle 11 is detachably fixed to the upper part of the valve stem 8. By rotating the handle 11, the valve stem 8 is moved up and down. The valve stem may be moved up and down using fluid pressure such as air pressure, magnetic force, or the like. When the valve stem 8 is lowered, its lowermost end presses the diaphragm 9, and the diaphragm 9 deforms elastically and then plastically, and the center of the diaphragm 9 moves downward, but within the range of the elastic deformation of the diaphragm 9. The distance between the diaphragm 9 and the seat 7, that is, the lift, is determined so that the central portion of the diaphragm 9 comes into pressure contact with the seat 7 of the main body 1, thereby closing the valve. After this, when the valve stem 8 is raised, the diaphragm 9 follows the valve stem 8 and rises, and elastically returns to its original shape. That is, the diaphragm 9 is deformed within the elastic deformation range to close the valve. This diaphragm 9 is pushed down by the valve stem 8 and brought into a fully closed state.
The shape of the diaphragm 9 that allows the diaphragm 9 to follow the valve stem when the valve stem 8 is then raised to open the valve will be described. FIG. 2 is a longitudinal sectional view of the diaphragm 9, which has a partial spherical shell shape with a large curvature. In FIG. 2, the radius of curvature of the diaphragm is R, the thickness of the diaphragm is t, and the angle formed by the straight line connecting the center of curvature of the diaphragm and both ends of the diaphragm is 2β. When the diaphragm 9 having this shape is pushed by the valve rod 8 with a load of Pkg, the amount of deformation of the diaphragm is assumed to be δmm (Fig. 3). FIG. 4 shows an example of the relationship between P and δ when α=Rβ2/l is used as a parameter. In FIG. 4, when the value of the load P is small, the diaphragm deformation is approximately in the elastic range. That is, if the range of elastic deformation is, for example, P < 7 kg, then when α=2.1, the range of elastic deformation is when the displacement δ is approximately 0.4 mm or less,
Therefore, the lift can only be taken up to a maximum of about 0.4mm L. Similarly, when α=3.2.5634.5.37, the lift can be taken up to a maximum of about 0.6, 0.8.0, and 9mm, respectively. becomes. That is, when the value of α is large, the amount of deformation δ of the diaphragm within the elastic deformation region is large. Therefore, if α is set to a large value, the flow rate when the valve is fully open will be large, and the flow resistance will be small. However, when α=6.27, there is a region of P×0. this is,
In this region, the diaphragm 9 cannot be returned to its original shape unless a force is applied to pull the diaphragm upward, and it is difficult to use it as a valve unless the lower surface of the valve stem 8 and the upper surface of the diaphragm 9 are bonded together. Since the present invention does not have a configuration in which the valve stem and diaphragm are bonded,
When α=6.27, the maximum shift is about 0.55m5j
, therefore, in the example of FIG. 4, it is preferable that α=5.34 or α=5.37. The curve shown in FIG. 4 represents the change in load P when the amount of displacement δ is increased, such as when the valve stem 8 is screwed into the through hole. It represents the change in the displacement amount δ when the load P is increased, such as when pneumatic pressure or the like is applied to the valve stem 8. That is, when α=5.34, a large deformation occurs due to jump buckling in which the displacement δ suddenly increases from the upper limit buckling value A. Whether or not the lower limit buckling value B has a negative value in large deformations due to jump buckling, such as when α = 6.27 in Figure 4, depends on the material of the diaphragm 9 and the value of α. Although it depends on the method of fixing the peripheral edge of the diaphragm 9, when the peripheral edge is rigidly fixed, the lower limit buckling value B does not have a negative value. Therefore, it is sufficient to set the lift so that when the valve stem 8 is lowered, the diaphragm 9 is pressed against the seat 7 within the range of elastic deformation, and when the valve stem 8 is raised, the diaphragm 9 will always return to its original state. Return to shape. In this embodiment, a sheet 7 made of synthetic resin or the like is attached to the upper end of the upward flow path 5 to serve as a valve seat. However, by coating the diaphragm 9 with synthetic resin, etc., the upward flow path 5
The upper end may be shaped like a protruding valve seat while the main body is made of metal. Further, the shape of the diaphragm 9 can be a trapezoidal shape that bulges upward, and a plurality of diaphragms can be stacked and used. [Effects of the Invention] The effects of the present invention are as follows. a. Since there are no air-friction sliding parts such as springs or valve bodies in the contact area of the passing fluid inside the valve, no metal powder is generated due to contact wear, and there is no seat leakage due to the generated metal powder getting into the seat surface. There is no metal powder contamination in the piping system. b. The valve does not have a valve body that is prone to eccentricity when opening and closing, and the valve is opened and closed only by the valve stem that fits into the through hole in the lid and is less prone to eccentricity, preventing sudden opening and closing of the valve and turbulent flow of fluid. It maintains a reliable seal for a long time even if there is a problem. C. Since a thin sheet metal bulging upward is used as the diaphragm, a large lift can be achieved, and a valve with low flow resistance can therefore be obtained.

Claims (1)

[Claims] A main body with an open upper part and an inlet and an inlet on the left and right sides, and an upward flow path connected to the inlet in the center, a lid attached to the upper part of the main body, and a lid that penetrates the center of the lid and has this penetrating part. It consists of a valve stem that is screwed, and a diaphragm that is held between the main body and the lid at their outer peripheries,
By lowering the valve stem and simultaneously lowering the diaphragm that is in contact with the valve stem, the valve is closed by pressing the diaphragm at the end of the upward flow path of the main body, and by making the lowered diaphragm into an elastic deformation region. A diaphragm seal valve characterized in that the valve is opened by raising the valve stem and raising the diaphragm.