JPS62165074A - Openable valve - Google Patents

Abstract

PURPOSE:To reliably prevent the leakage of a fluid, by integrally forming a valve member with a sealing portion for sealing a space between the periphery of the valve member and an accommodation hole, and welding the outer periphery of the sealing portion to the opening edge of the accommodation hole. CONSTITUTION:A body 1 formed of fluoro-synthetic resin is formed at the center of its upper surface with an accommodation hole 5 communicated with an inlet opening 2. The accommodation hole 5 accommodates a valve member 10 formed of fluoro-synthetic resin and adapted to come into abutment against and separation from a valve seat 8 at the outer periphery of the lower end surface, thereby opening and closing a valve opening 7. The valve member 10 is integrally formed with a vertically expandable bellows 12 at the upper surface of a large-diameter portion. The bellows 12 is integrally formed at its upper end with a mounting plate 15. A melt bonding portion 13 is formed between the outer periphery of the mounting plate 15 and a shoulder 16, thereby integrally connecting the mounting plate 15 to the opening edge of the accommodation hole 5.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an on-off valve suitable for controlling the opening and closing of a flow path for a highly corrosive or toxic fluid.

Problems to be Solved by the Prior Art and the Invention The general structure of an on-off valve that controls opening and closing of a fluid flow path is to place a valve seat around a valve port provided in a flow path that communicates an inlet and an outlet. A housing hole opened on the outer surface of the formed body is formed, and a valve body that approaches and separates from the valve seat to open and close the valve port is housed in the housing hole, and this valve body is attached to the outside of the body. It has a structure in which it is connected to the rod and sealed between the output rod and the accommodation hole, and rubber material is used to completely seal between the output rod and the accommodation hole.

When the fluid used is a highly corrosive or toxic chemical solution or gas, the rubber material corrodes and erodes, causing leakage to the outside, and the corrosion resistance of the body and valve body that come into direct contact with these fluids becomes a problem. , there is a problem with tactility.

Therefore, in the past, the body and valve body were made of fluorine-based synthetic resin with excellent corrosion resistance, and, for example, the valve body was sealed between its surroundings and the accommodation hole, and the valve body was made of a material that could be freely deformed in the operating direction. A bellows is integrally molded and accommodated in the accommodation hole, and the opening of the accommodation hole is closed by pressing the peripheral edge of the opening edge of the bellows against the opening edge of the accommodation hole with the lower surface of the drive device attached to the body by tightening bolts. Some products are designed to be completely sealed, but since the body is made of synthetic resin, creep occurs and the tightening force with bolts becomes loose, and the periphery of the bellows, which is made of the same material, also tends to creep. As a result, a gap is created at the joint between the opening edge of the accommodation hole and the peripheral edge of the bellows, and the sealing of the opening of the accommodation hole, which was perfect at the time of assembly, is improved. As time passes, the fluid deteriorates and leaks to the outside.Furthermore, although fluorine-based synthetic resins have excellent corrosion resistance, they have a large coefficient of thermal expansion, so they cannot be used in environments with large temperature differences. Large distortions tend to occur due to thermal expansion, and this similarly creates a gap at the joint between the opening edge of the accommodation hole and the peripheral edge of the bellows, resulting in external leakage of fluid, resulting in poor reliability.

Means for Solving the Problems The present invention, as a means for solving the above-mentioned problems, provides a method using a fluorine-based resin in which a valve seat is formed around a valve port provided in a flow path that communicates an inlet and an outlet. A housing hole is formed in the outer periphery of the body, and a valve body made of a fluorine-based resin is housed in the housing hole, and the valve body is made of a fluorine-based resin and opens and closes the valve port by moving into and out of contact with the valve seat. In an on-off valve connected to an output rod of an externally attached drive device, the valve body has a sealing part that seals between the periphery of the valve body and the accommodation hole and is free to deform in the operating direction of the valve body. It is integrally molded, and the peripheral edge of the sealing part is integrally joined to the opening edge of the accommodation hole by welding.

Functions and Effects The on-off valve of the present invention has the above-mentioned structure, and since the peripheral edge of the sealing part is integrally joined to the opening edge of the accommodation hole by welding, the opening of the accommodation hole is completely sealed, and it is prevented from creeping or thermal expansion. Even if distortion occurs, there will be no gap in the joint, and therefore, it is certain that fluid will leak out from the opening of the storage hole even if used for a long time or in an environment with severe temperature changes. This has the effect of significantly improving reliability.

Example Embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 shows the first embodiment, and in Fig. 1, ``■'' is a body made of fluorine-based synthetic resin and has an inlet 2 and an outlet 3 formed on both end faces, respectively. A storage hole 5 that communicates with the inlet 2 is drilled, and a communication hole 6 that communicates with the outlet 3 is drilled in the center of the bottom of the hole, so that chemical liquids, medicinal gases, etc., which reach the outlet 3 from the inlet 2 can be stored. The rim of the above-mentioned flow hole 6 forms a valve lower, and the bottom surface of the accommodation hole 5 around this valve lower serves as a valve seat 8. . The accommodation hole 5 accommodates a valve element 10 which is also made of fluorine-based synthetic resin and whose peripheral edge on its lower end surface approaches and separates from the valve seat 8 to open and close the valve lower. Upper and lower extendable bellows 12 are integrally molded to the upper surface, and a mounting plate 15 having a through hole 14 in the center is integrally formed at the upper end of the bellows 12.

This mounting plate 15 has its peripheral edge fitted into a step 16 formed at the opening edge of the accommodation hole 5, and a fused joint 13 is formed over the entire circumference between the peripheral edge and the step 16 by welding or welding. By doing so, it is integrally connected to the opening of the receiving hole 5. An air cylinder 17 is fixed to the upper surface of the body 1, and a piston rod 22 is fixed to a piston 20 which is urged downward by the elastic expansion force of a compression coil spring 21.
The tip of the bellows 12 is inserted into the bellows 12 through the through hole 14 of the mounting plate 15, and the male thread 23 formed at the tip is inserted into the valve body lO.
Normally, the lower surface of the valve body 10 is pressed against the valve seat 8 by the elastic expansion force of the compression coil spring 21, and the valve lower is closed. By supplying air to the air supply port 25 of the cylinder 17, the piston 20 moves upward against the elasticity of the compression coil spring 21, and as a result, the lower surface of the valve body lO is separated from the valve seat 8, and the valve lower In this embodiment, the peripheral edge of the mounting plate 15 of the valve body 10 is integrally connected to the step 16 of the opening edge of the accommodation hole 5 by welding or welding, so that the The opening of the housing hole 5 is completely sealed with no gap around the entire circumference, and there is no possibility that the opening edge of the housing hole 5 or the mounting plate 15 will be distorted due to creep or thermal expansion. However, there will be no gap at the joint.

FIG. 2 shows a second embodiment of the present invention, in which a valve port 32 is formed in the center of a body 31 made of fluorine-based synthetic resin with an inlet 2 and an outlet 3 formed on both end faces, respectively. A valve seat 33 is formed on the upper surface of the opening edge, a housing hole 34 is formed in the center of the upper surface of the body 31, and a diaphragm 35 also made of fluorine-based synthetic resin is housed in the housing hole 34. This diaphragm 35 has a male thread 37 on the outer periphery on the upper surface of the central portion which becomes the valve body 36 that approaches and separates from the valve seat 33.
The mounting portion 38 has a protruding shape and a mounting ring 40 is formed on the peripheral edge thereof.
The periphery of the housing hole 34 is fitted into the step 43 formed at the opening edge of the accommodation hole 34, and a fused joint 41 is formed over the entire circumference between the periphery and the step 43 by welding or welding, as in the previous embodiment. It is integrally connected to the opening of the receiving hole 34 by forming a . A solenoid 44 is attached to the upper surface of the body 31, and the tip of a plunger 45 of the solenoid 44 is fitted into the housing hole 34, and a female thread 46 is formed on the lower end surface.
is screwed into the male thread 37 of the mounting portion 38 of the diaphragm 35, and is connected to the upper surface of the valve body 36 with a packing 47 interposed between the plunger 45 and the fixed core 48. The elastic expansion force of the coil spring 50 urges the valve body 36 downward, and the valve body 36 is normally pressed against the valve seat 33 to close the valve opening 32.
is closed, and by energizing the solenoid 44, the plunger 45 moves upward against the elasticity of the compression coil spring 50, and accordingly, the valve body 36 is separated from the valve seat 33, and the valve port 32 is opened. In this embodiment as well, the peripheral edge of the diaphragm 35 is integrally connected to the step 43 at the opening edge of the accommodation hole 34 by welding or welding.
Similar to the embodiment described above, the opening of the accommodation hole 34 is completely sealed, and the accommodation hole 34 is completely sealed due to creep or thermal expansion.
Even if the opening of 4 or the mounting ring 40 is distorted, no gap will be generated at the joint.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention, and FIG. 2 is a sectional view of a second embodiment.

Claims (1)

[Claims] A housing hole opened on the outer periphery is formed in a body made of fluorine-based resin in which a valve seat is formed around a valve port provided in a flow path that communicates an inlet and an outlet, and a housing hole is formed in the housing hole to accommodate the valve seat. In the on-off valve, which houses a valve body also made of fluorine-based resin that approaches and separates to open and close the valve port, the valve body is connected to an output rod of a drive device attached to the outside of the body. A sealing part that seals between the circumference of the valve body and the accommodation hole and is free to deform in the operating direction of the valve body is integrally molded, and the peripheral edge of the sealing part is welded or welded to the opening edge of the accommodation hole. An on-off valve characterized by being integrally connected