JPH031675Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to the improvement of a joint, and particularly to a joint that can maintain airtightness without being affected by tightening force.

(Prior art) The conventional joint is as shown in Fig. 5.
No. 26151) The push rod 3 is slidable inside the main body 1,
A flat ring-shaped gasket 4 interposed between the main body 1 and the push rod 3 is tightened with a nut 6 to maintain airtightness. and 3b are both perpendicular to the axis of the joint, so if the nut 6 is tightened with excessive force, the force will be applied perpendicularly to the face of the gasket 4 as shown by the solid arrow as shown in Figure 6a, but the gasket 4 Since the surface is flat, the gasket 4 extends in the inner and outer radial directions as shown by the broken line arrows.
When there is not enough room to extend in the inner diameter direction, the outer diameter of the gasket 4 becomes larger than the thread diameter of the inner diameter of the nut 6, as shown in Fig. 6b, and it bites into the thread, deforming the gasket 4 and causing gas leakage. There are drawbacks such as the push rod 3 cannot be removed from the nut 6 during service, and other joints cannot be connected.

(Problems to be solved by the invention) Therefore, the present invention aims to solve the above-mentioned problems of conventional joints by simple processing and provide a joint that can maintain airtightness without being affected by tightening force. .

(Means for solving the problem) Therefore, the present invention provides a joint in which airtightness is maintained by a flat ring-shaped gasket interposed between the main body and the push rod, and the inner diameter D ₁ of the gasket is set to the push rod. The outer diameter _D2 of the gasket insertion portion is slightly larger than that of the main body, and the gasket abutting surface of the main body is tapered so that the inner circumferential side is farther away from the gasket surface from the outer circumference toward the inner circumference.

(Function) By configuring the present invention as described above, even if the tightening force becomes somewhat excessive, the gasket can
A tightening force is applied to the gasket obliquely from the outer periphery to the inner periphery, and the gasket deforms sequentially from the outer periphery to the inner periphery along the gasket abutting surface of the main body, thereby maintaining airtightness.

(Example) The present invention will be described in detail below based on FIGS. 1 to 4 showing examples.

FIG. 1 shows a first embodiment of a joint with a check valve according to the present invention.

In the figure, the joint with a check valve consists of a male joint and a female joint. The male side joint is the main body 1
It consists of a valve body 2 that functions as a normally closed check valve, and a push rod 3 that presses the valve body 2 in the valve opening direction, and the push rod 3 is slidable with respect to the main body 1. A gasket 4 is interposed between the push rod 3 and the contact surface 1a of the main body 1 to maintain airtightness. Gasket 4 contact surface 1 of main body 1
a is gasket 4 on the inner circumference side from the outer circumference toward the inner circumference.
It is tapered (approximately 5 degrees) away from the surface. And inside there is a fluid passage 7 that penetrates in the axial direction.
is provided, and the valve body 2 is pressed by a spring 10 to close the fluid passage 7. Further, a screw is carved on the outer periphery to be screwed into a nut 6, which will be described later.

The push rod 3 also has a fluid passage 8 inside and a main body 1.
A tapered portion 3a is formed at the end opposite to the push rod 3, thereby allowing the push rod 3 to also serve as a flare mouthpiece. The inner diameter D ₁ of the gasket 4 is equal to the outer diameter D ₂ of the gasket 4 insertion portion of the push rod 3.
It is formed to be slightly larger.

On the other hand, the female side joint includes a pipe 5 (not shown) whose one end is flared and comes into contact with the tapered part 3a of the push rod 3, and whose other end is connected to a gas injection device or the like.
It consists of a nut 6 which is screwed into the main body 1.

To explain the case of connecting a gas injection device or the like to a joint with a check valve as described above, when the flared part of the pipe 5 is brought into contact with the tapered part 3a of the push rod 3 and the nut 6 is tightened to the main body 1, the push rod 3 moves inside the main body 1, and its tip pushes the valve body 2 against the spring force of the spring 10 until the push rod 3 comes into contact with the gasket 4, thereby opening the valve body 2. Then, the fluid passage 7 inside the main body 1 is communicated with a gas injection device etc. via the fluid passage 8 inside the push rod 3 and the pipe 5, and gas injection is performed.

At this time, airtightness is maintained by a flat ring-shaped gasket 4 interposed between the main body 1 and the push rod 3, but even if the nut 6 is slightly overtightened,
As shown in FIG. 2a, the gasket 4 abutting surface 1a of the main body 1 is tapered so that the inner periphery side becomes farther away from the gasket 4 surface from the outer periphery toward the inner periphery. As force is applied diagonally in the circumferential direction, the inner diameter D ₁ of the gasket 4 becomes smaller from the outer circumference to the inner circumference, and the inner circumference side gradually becomes thicker along the taper of the main body 1. However, the inner diameter D ₁ of the gasket 4 Since the outer diameter _D2 of the gasket 4 insertion part of the push rod 3 is formed slightly larger, there is no problem (Fig. 2b), and thus airtightness can be maintained even if the nut 6 is slightly overtightened. It is.

Note that during normal times when the above-mentioned gas injection is not performed, this portion is closed with a cap nut (not shown) or the like instead of the nut 6 and pipe 5.

Next, FIG. 3 shows a second embodiment in which the joint of the present invention is applied to a filter joint installed at a fluid inlet of a solenoid valve or an expansion valve. Although omitted, 3 is a push rod that serves as a filter head, and 11 is a filter, which removes dust and the like from the fluid flowing from the pipe 5 side to the main body 1 side.

Furthermore, FIG. 4 shows a third embodiment in which the joint of the present invention is applied to a fusible plug with a check valve. This is to prevent abnormal rise in refrigerant pressure due to abnormal high temperature such as fire, and to prevent damage to the air conditioner due to abnormal high pressure.

This is also roughly the same as the first embodiment, so the detailed structure will be omitted, but a fusible alloy 12 is cast into the fusible head that acts as the push rod 3, and the fusible alloy 12 When the temperature reaches a specified temperature or higher, the refrigerant melts and is extruded by the pressure within the refrigerant system, and the refrigerant is discharged outdoors through the pipe 5. At this time, valve body 2
Although it comes into contact with the tip of the push rod 3 as shown by the dotted line, it does not come into contact with the seat portion of the main body 1, so it does not prevent the release of the refrigerant.

In addition, when the temperature does not reach the melting temperature but is close to the melting temperature and the fusible alloy part becomes distorted and a minute refrigerant leak occurs, the nut 6 can be removed to replace only the push rod 3. When the fusible head is removed, the valve body 2 is pressed against the seat part of the main body 1 due to the pressure difference inside and outside the refrigeration system, making it possible to replace only the fusible head of the push rod 3 without releasing refrigerant to the outside. be.

In this fusible plug with a check valve, the gasket 4 has the same function as that of the first embodiment, and maintains complete airtightness. Note that 13 is a valve body retaining pin.

(Effect of the invention) Since the joint of the present invention has the structure and function as described above, when the gasket interposed between the main body of the joint and the push rod is tightened with a nut to maintain airtightness between the two. Even if the nut tightening force becomes somewhat excessive, the thickness of the gasket becomes thicker from the outer circumference to the inner circumference, and does not extend in the inner and outer radial directions, completely maintaining airtightness between the main body and the push rod.

[Brief explanation of the drawing]

Figures 1 to 4 show the joint of the present invention.
The figure shows the first embodiment applied to a joint with a check valve, Figures 2a and b are explanatory diagrams, and Figures 3 and 4 show the present invention applied to a filter joint and a fusible plug with a check valve, respectively. The second and third embodiments and FIG. 5 show joints of conventional devices, and FIGS. 6a and 6b are explanatory diagrams thereof. 1... Main body, 1a... Contact surface, 3... Push rod, 4
...Gasket.

Claims (1)

[Scope of utility model registration request] In a joint in which a push rod 3 is slidable within the main body 1 and airtightness is maintained by a flat ring-shaped gasket 4 interposed between the main body 1 and the push rod 3, the inner diameter D ₁ of the gasket 4 is defined as the push rod. The outer diameter D ₂ of the gasket 4 insertion part of No. 3 is slightly larger than that of the main body 1, and the gasket 4 contacting surface 1a of the main body 1 is tapered so that the inner circumferential side is farther away from the gasket 4 surface from the outer circumference toward the inner circumference. fittings.