JPH0425598Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a cap nut and a screw seal mechanism that prevent fluids such as gas, air, water, oil, and chemicals from leaking from connection ports.

(Conventional technology) For connection fittings for gas appliances, air appliances, etc.
Rubber gaskets are used to seal the sealing surface of the tightening parts of screws, but rubber gaskets have a problem with their corrosion resistance against highly corrosive gases and chemicals, so they are limited to locations where they can be used for long periods of time. There is.

As a solution to this problem, there is a known method in which a metal sealing pad is integrally provided so that the screw can be sheared at the same time as the screw is tightened (for example, Utility Model Publication No. 45-36689).

(Problem to be solved by the invention) The known method described in the conventional technology has a ring-shaped outer flange integrally formed under the head and neck of the bolt, but the connecting part between the flange and the bolt shaft is Because they are connected in spots at several places on the circumference, and separated in other places, twisted protrusions remain at the site of separation, which becomes an obstacle to surface crimping. The problem is that you can't get a seal. Furthermore, since this sealing collar is formed as an outer collar on the male threaded portion, its use is necessarily limited to the outside, and there is a problem in that it is impossible to seal the inside of the connection port of the socket body and the inside of the cap nut at all.

The present invention was devised in view of the problems of the conventional technology, and its purpose is to improve the adhesion between the two opposing sealing surfaces in the screw hole for a long period of time. The object of the present invention is to provide a cap nut and a screw sealing mechanism that can completely eliminate leakage.

(Means for Solving the Problems) In order to achieve the above object, the cap nut of the present invention has an annular groove 4 formed at the back of the screw hole 3 of the cap nut body 2 with an inner diameter larger than the thread diameter of the female threaded portion 3a. At the same time, an annular inner flange 5 having an inner diameter smaller than the thread diameter of the female threaded part 3a is formed in the middle of the annular groove 4 to be the same body as the cap nut body 2. When pushed by the tip 1a, it is sheared or displaced, and is pressed between the tip 1a and the inner end surface 3b of the screw hole 3 of the cap nut body 2, so that it acts as a seal packing.

In addition, in the screw seal mechanism, the male threaded body 1
An annular groove 14 with an inner diameter larger than the thread diameter of the female thread part 13a is provided at the back of the screw hole 13 of the socket body 12 into which the socket body 12 is screwed and tightened, and an annular groove 14 with an inner diameter smaller than the thread diameter of the female thread part 13a is provided in the middle of this annular groove 14. An annular inner and outer flange 15 as a sealing gasket for the inner diameter is formed in the same body as the socket body 12, and the annular inner flange 15 is sheared or displaced by screwing and tightening the male threaded body 10 to connect the tip surface 10a of the male threaded body and the thread of the socket body 12. It is designed to be pressed between the inner end surface 13b of the hole and the inner end surface 13b of the hole.

(Function) In FIG. 2, as the cap nut body 2 is fitted onto the male thread body 1, the front surface of the annular inner flange 5 of the cap nut body 2 comes into contact with the tip 1a of the male thread body 1, but the screw continues to tighten. As it is inserted, the inner flange 5 is deformed so as to be pushed backwards, and the inner end surface 3b at the back of the screw hole is deformed.
It is pressed against it and becomes compressed, and finally, when it exceeds its limit, it is sheared from the root, resulting in the shape shown in Figure 1.
This sheared inner flange 5 is made of the same metal as the cap nut, and since it is strongly pressed between the two parallel opposing surfaces, it functions as a seal packing.

Although FIG. 1 shows a case in which the inner flange 5 is sheared, it can also be in a state in which it is pressed and displaced without being sheared.

FIG. 2 shows a case where a similar sealing mechanism is constructed in the socket body 12, and the operation is exactly the same as in the case of FIGS. 1 and 2.

By providing an annular outer flange at the lower neck portion on the side of the male threaded body 1, the sealing function can be achieved at two locations, inside and outside.

(Example) Although the top plate of the cap nut body 2 shown in FIG. 1 is completely closed, it can also be implemented with an opening 2a provided as shown in FIG.

The cap nut having the opening 2a is used as a union nut or the like.

Figure 4 shows a case where an annular inner flange 15 serving as a sealing mechanism is provided on a socket body 12 serving as an inlet/outlet or connection port for fluid, into which a male threaded body 10 as a screw cap or connecting fitting is screwed and tightened. be.

The material of the cap nut body 2 or the socket body 12 is suitably a material with high toughness such as a metal such as iron or mild steel.

(Effects) Since the present invention is configured as described above, it produces the following effects.

By forming an annular inner flange in the screw hole of the cap nut or socket body, it is sheared or press deformed as it is screwed into the male screw body and is strongly pressed between the two opposing surfaces to exert a sealing effect. However, since it is made of the same metal, it has very good sealing properties and there is no need to consider corrosion resistance. In addition, a sealing part is incorporated inside and deep inside the screw hole, so that it is not exposed to the outside, so that the appearance is not damaged and there is no fear that it will be intentionally disturbed.

The sealing mechanism to which the present invention is applied is suitable for sealing gases such as gas and air, liquids such as water and oil, and various fluids such as powder.

[Brief explanation of drawings]

Fig. 1 is a vertical side view of the cap nut according to the present invention after screwing, Fig. 2 is a partial longitudinal side view of the same before screwing, and Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2. 4 is a longitudinal sectional side view of a connection port socket body to which the present invention is applied, and FIG. 5 is an enlarged sectional view of the main parts of the same. 1, 10...male thread body, 2...cap nut body,
3, 13... Screw hole, 4, 14... Annular groove, 5,
15... Annular inner flange, 1a, 11a... Tip, 3
a, 13a...Female screw portion, 3b, 13b...Inner end surface, 12...Socket body.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a cap nut that is screwed and tightened onto a male threaded body 1, an annular groove with an inner diameter larger than the thread diameter of the female threaded portion 3a is provided at the back of the screw hole 3 of the cap nut body 2. 4 is provided, and an annular inner flange 5 having an inner diameter smaller than the thread diameter of the female threaded portion 3a is formed in the middle of the annular groove 4 to be the same body as the cap nut body 2. Tip part 1a when tightening
A cap nut characterized in that it is sheared or displaced when pushed by the cap nut and is pressed between the tip end 1a and the inner end surface 3b of the screw hole 3 of the cap nut body 2, thereby acting as a seal packing. (2) Socket body 12 for fluid inlet/outlet or connection port, etc.
In a screw fastening mechanism in which a male threaded body 10 is screwed and tightened into a threaded hole 13, an annular groove 14 having an inner diameter larger than the thread diameter of the female threaded portion 13a is provided at the back of the threaded hole 13, and this annular groove 14
An annular inner flange 15 serving as a sealing packing having an inner diameter smaller than the thread diameter of the female threaded portion 13a is provided in the middle thereof.
is formed into the same body as the socket body 12, and by shearing or displacing the annular inner flange 15 by screwing and tightening the male thread body 10, a hole is formed between the tip surface 10a of the male screw body and the inner end surface 13b of the screw hole of the socket body 12. A screw seal mechanism characterized by being compressed.