JP2594289Y2 - Male thread for pipe for low pressure - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a low-pressure male pipe thread for a low pressure pipe which can be screw-connected with a seal and a certain degree of connection strength being ensured, whether it is a parallel female thread for a pipe or a tapered female thread for a pipe. The present invention can be applied to a tube connection joint or the like for an air device.

[0002]

2. Description of the Related Art An air supply pipe for supplying air to an air device is usually connected to the air device through a joint.
The joint itself is attached so that the external thread formed on the joint is screwed into the internal thread on the air device side. Parallel screws for pipes and taper screws for pipes are often used as screws for attaching the above joints to air equipment.
Male and female threads for pipes of the same size (parallel male threads for pipes suitable for parallel female threads for pipes, and tapered male threads for pipes suitable for tapered female threads for pipes) are used. Then, at the time of connection of the joint, a sealing tape is wound around the male screw portion to avoid air leakage. This is because attachment of the joint to the pneumatic equipment requires a certain degree of connection strength and sealing properties.

However, with recent worldwide trends in the use of pipe threads, joints that can be screwed together in a state satisfying the above conditions regardless of whether the female thread portion formed on the air equipment is a parallel or tapered thread for pipes. The appearance of a male pipe thread) is desired.

[0004]

Therefore, in this invention , a parallel female thread portion for a pipe and a taper female thread portion for a pipe of the same size are used.
In any case, it is an object of the present invention to provide a male screw body for a low pressure pipe which can be screwed and connected in a state where the sealing property and a certain connection strength are secured.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to either a parallel female thread G for pipes or a tapered female thread R for pipes of the same size.
A tube for a male screw body that can be screwed also, it tapered female for the tube
In a male screw portion of the same size as the threaded portion R, a pipe tapered male screw portion 10 set to a length from the pipe end to a position corresponding to the reference diameter, and a little apart from a reference diameter portion of the pipe tapered male screw portion 10 And a projecting portion 11 which is larger than the reference diameter of the tapered male screw portion 10 for pipes provided until the tapered male screw portion 10 of the pipe substantially matches the reference diameter portions of the female screw portions G and R. When screwed in,
The pipe-shaped tapered male screw portion 10 or an annular seal member fitted around the vicinity thereof is pressed by the surface on which the female screw portions G and R are formed and the overhang portion 11 over the entire circumference.

[0006]

The present invention works as follows. Pipe taper
Male thread 10 is parallel female thread G for pipe or taper female for pipe
Screw until the reference diameter portions of the two substantially match the
When inserted, the female threads G and R are formed by the annular seal member.
The sealing property between the formed surface and the overhang portion 11 is ensured.
It is. And, in the sealed state, the tapered male screw for pipe is used.
Part 10 and parallel female thread G for pipe or tapered female thread R for pipe
Means that at least the reference diameter portion is screwed
ing. In other words, if the fluid pressure is low, the connection strength
There is no connection. Thus, for this tube
For a male threaded body, a parallel female thread G for pipes of the same size,
No matter which of the female internal thread portions R, it has good sealing properties.
Screw connection can be performed in a state where a sufficient connection strength is secured.

That is, with this male pipe thread, any one of the parallel female thread G for pipe and the tapered female thread R for pipe can be threadedly connected with sealing performance and a certain degree of connection strength secured.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of the present invention. In this embodiment, as shown in FIG. 1, a tube connecting fitting 12 is formed by providing a tube connecting tool 12 to a pipe male screw body 1 of the present invention, and a connecting female screw on a pneumatic device 4 side. The connection can be made in a state where the sealing property is ensured, regardless of whether it is a parallel female screw portion for pipe or a tapered female screw portion for pipe.

As shown in FIG. 1, the joint T is basically composed of the tube connector 12 and the tapered male thread 10 for pipe.
It is constructed by connecting a pipe male screw body 1 having
It is formed in a cylindrical shape with both ends open as a whole. Taper pipe male thread portion 10, the tube lengths that are useful thread is formed
The length from the end to the position corresponding to the reference diameter is set (for example, in the case of a tapered male screw for R1 / 8, the length is 3.97 mm).

The tube connector 12 expands the diameter of an annular plate having a locking claw on an inner peripheral portion by a pushing operation of the operation tube 13 shown in FIG. 1, and places the tube 9 in the annular plate through the operation tube 13. After the insertion, the pressing force of the operation cylinder 13 is released to reduce the diameter (return the shape) of the annular plate, thereby connecting the tube 9 in a retaining state (known technology). And in this embodiment, the tube connector 12
The part of the surface of the tapered male thread portion 10 protruding outward from the plane area of the pipe 10 functions as the overhang portion 11 described in the section of means.

In this embodiment, the annular seal member S is externally fitted to the pipe tapered male thread 10 or a portion in the vicinity thereof, and the pipe tapered male thread 10 is connected to the pipe parallel female thread G or the pipe taper female thread. 2 and 3, at least the vicinity of the reference diameter of the tapered male thread portion 10 for the pipe and the vicinity of the open portions of the female thread portions G and R ( near the reference diameter) as shown in FIGS. State. Therefore, in this state, the joint T does not accidentally separate from the air device 4.

Further, in the above state, the tapered male thread portion 1 for pipes is used.
Since the annular seal member S fitted to the outside is pressurized all around by the surface on which the female threads G and R formed on the pneumatic device 4 are formed and the overhang portion 11, the taper male screw for pipe is used. Even if the fluid leaks from between the portion 10 and the internal thread portions G and R, the fluid does not leak out of the joint T. As shown in FIGS. 4 and 5, even if the amount of threading of the tapered male thread portion 10 for the pipe into the female thread portions G and R is slightly different from the appropriate amount, the same operation and effect as in the above case can be obtained. .

[0013]

[Effects of the Invention] Since the present invention has the above-described configuration, the following effects are obtained. From the contents described in the column of action,
Parallel female threads for pipes and tapered female threads for pipes of the same size
Even if it is misaligned, a male screw body for a pipe for low pressure can be provided which can be screwed and connected with the sealing property and a certain connection strength secured.

[Brief description of the drawings]

FIG. 1 is a diagram showing a state in which a joint having a male screw body for a pipe according to the present invention is screwed into an air device.

FIG. 2 is a cross-sectional view showing a state where a pipe tapered male screw portion of the joint is screwed into a pipe tapered female screw portion.

FIG. 3 is a sectional view showing a state in which a pipe tapered male screw portion of the joint is screwed into a pipe parallel female screw portion.

FIG. 4 is a cross-sectional view when the amount of screwing of the pipe tapered male screw into the female screw is smaller than appropriate.

FIG. 5 is a cross-sectional view in a case where the amount of screwing of the pipe tapered male screw into the female screw is larger than appropriate.

[Explanation of symbols]

 G Parallel female thread for pipe R Tapered female thread for pipe 1 Male screw for pipe 4 Air equipment 10 Tapered male thread for pipe 11 Overhang

Claims (2)

(57) [Scope of request for utility model registration] 1. A parallel female thread portion (G) for a pipe of the same size , a pipe
Male threaded body for pipes that can be screwed into any of the tapered female threaded parts (R) for pipes.
Male taper part for pipe set to length from pipe end to position corresponding to reference diameter in male thread part
And a projecting portion (11), which is provided at a position slightly away from a reference diameter portion of the pipe tapered male screw portion (10), and is larger than a reference diameter of the pipe tapered male screw portion (10). The male thread (10) is the female thread (G)
(R), when they are screwed into each other until their reference diameters substantially match each other, the pipe-shaped tapered male screw part (10) or an annular seal member fitted around the pipe taper male screw part (10) becomes a female screw part (G).
A male screw body for a pipe for low pressure, characterized in that the entire circumference is clamped by the surface on which (R) is formed and the overhang portion (11). 2. The male thread according to claim 1, further comprising a tube fitting (12).