JP2001173868A - Synthetic resin made tube fitting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a synthetic resin made tube fitting capable of avoiding concentration of stress to a branch part on the synthetic resin made tube fitting of cheese, elbow, etc., and an inside part of a bent part while restraining increase of product weight to the minimum. SOLUTION: A stepped part 21 of an inside part 17 of a branch part and a bent part of a stopper 16 for connecting pipe end part contact provided at a socket deep part of a fitting is formed higher than a stepped part 22 of an outside part 18 of the branch part and the bent part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a synthetic resin pipe joint, and more particularly, to a synthetic resin pipe joint such as a cheese having a branch portion and an elbow having a bent portion.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show an example of a conventional synthetic resin pipe joint. FIG. 4 is a sectional front view and FIG. 5 is a side view. This synthetic resin pipe joint is a branch pipe joint 10 called a so-called cheese. On both sides of a straight tubular main body portion 11, sockets 12 for connecting main pipes are provided, respectively. Is provided with a branch pipe connection port 13 on the side.

A small-diameter portion 14 coaxial with the receiving port is provided at the back of each of the receiving ports 12 and 13, and a pipe connected to a step between the small-diameter section 14 and the receiving ports 12 and 13 is provided. A stopper 16 with which the front end of the stopper 15 contacts is formed. Since the small-diameter portion 14 is provided coaxially with the receiving ports 12 and 13, the step in the stopper 16 has the same height over the entire circumference.

[0004]

When such a branch pipe joint 10 is used for a fluid having a high pressure, for example, a pipe for tap water, the pressure of tap water acts so as to open the receiving port 12 and the receiving port 13. As a result, stress concentrates on the inside portion 17 of the branch portion, and a large stress is generated as compared with other portions. Further, when a large stress is applied by the water hammer, there is a possibility that the branch portion inner portion 17 may be broken due to the concentration of the stress.

For this reason, the step of the stopper 16 is increased to increase the thickness of the small diameter portion 14 to increase the overall strength. However, even in this case, the stress concentration on the inner portion 17 of the branch portion is performed. Cannot be avoided and the degree of fatigue is still higher than other parts. In addition, the product weight increases, which affects the manufacturing cost. The same applies to an elbow having a bent portion, and a countermeasure has been required.

Therefore, the present invention provides a synthetic resin pipe joint which can avoid concentration of stress on the inside of the branch portion and the bent portion of a synthetic resin pipe joint such as a cheese or an elbow while minimizing an increase in product weight. It is intended to provide a resin pipe joint.

[0007]

In order to achieve the above object, a synthetic resin pipe joint according to the present invention is a synthetic resin pipe joint having a branch portion such as a cheese or an elbow, and a bent portion. In the connecting pipe end contact stopper provided at the back, the step at the inside of the branch and the bent part is formed higher than the step at the outside of the branch and the bent part. Part, the step inside the bent part,
It is characterized in that the height is not more than four times the height of the step at the outside of the branching portion and the bent portion.

[0008]

FIG. 1 is a side view showing an embodiment of a synthetic resin pipe joint according to the present invention, and FIG. 2 is a sectional view of a main part showing a comparison between a conventional product and a product of the present embodiment. . In the following description, the same components as those of the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

This pipe joint made of synthetic resin is a branch pipe joint 1 called a cheese which is the same as the pipe joint shown in FIGS.
0, receiving ports 12 for connecting the main pipes on both sides of the straight tubular main body 11 and receiving ports 1 for connecting the branch pipes on the sides of the main body 11.
3 are provided.

In such a branch pipe joint 10, in the present embodiment, the main pipe connection port 1 of the stopper 16 is provided.
Branch portion inner portion 1 between 2 and branch pipe connection port 13
The step 21 of 7 is higher than the step 22 of the outer portion 18 of the branch portion, and the thickness of the small diameter portion 14 in the inner portion 17 of the branch portion is increased.

The height of the step 21 of the inside portion 17 of the branch portion may be set according to the diameter, thickness, etc. of each of the two receiving ports 12, 13.
The height is more than 4 times, preferably 2 to 3 times the height of 2, and even if the height of the step 21 is further increased, it is meaningless from the viewpoint of the overall strength and the weight of the product increases. It will increase the cost.

As described above, when a part of the step of the stopper 16 is made to be higher, only the vicinity of the branch inner portion 17 may be made to protrude inward, but a smooth curve is formed from the other steps. By gradually increasing the step size as drawn, the stress can be dispersed evenly throughout the joint. At this time, the range in which the step size is increased can be appropriately set according to the diameters of the receptacles 12 and 13, but usually, the opening angle of the receptacle 13 in both directions with respect to the axis is 45 degrees. Each time, that is, socket 13
Is preferably about 90 degrees from the viewpoint of stress dispersion and product weight.

The height of the step outside the above-mentioned range, for example, the height of the step 22 of the outer portion 18 of the branch portion may be the same as that of the conventional one or may be made as small as possible within the range of the standard. That is, the step 22 of the branch outer part 18 is the minimum height dimension within the standard, the height of the step 23 of the side part is the same as the conventional one, and the height of the step 21 of the branch inner part 17 is By setting the height dimension such that stress concentration can be avoided, it is possible to obtain a necessary and sufficient stress dispersion effect while suppressing an increase in product weight.

For example, when the step 24 on the entire circumference of the conventional product shown in FIG. 2A is about 1 mm, the product of the present embodiment shown in FIG. The height of the step is approximately 2.5 mm, the opening angle α is 90 degrees, and the height of the step is smoothly increased from 1 mm to 2.5 mm. 17 can be reduced by about 20% and can be dispersed throughout, and the increase in product weight can be suppressed to several percent or less.

In the present embodiment, the description has been made with respect to the port 12 for connecting the main pipe, but the same applies to the port 13 for connecting the branch pipe. FIG. It is sectional drawing which shows the other example of a pipe joint, and applied this invention to the elbow. Also in the elbow 30 having such a bent portion, the step 32 of the bent portion inner portion 31 is formed.
Is formed higher than the step 34 of the outer portion 33 of the bent portion, stress concentration on the inner portion of the bent portion can be avoided, and the strength of the entire product can be improved.

[0016]

As described above, according to the pipe joint made of synthetic resin of the present invention, it is possible to avoid stress concentration on the inside of the branch portion and the bent portion while suppressing an increase in product weight. The strength of the entire joint can be improved.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of a synthetic resin pipe joint of the present invention.

FIG. 2 is a cross-sectional view of a main part showing a conventional product and a product of the present embodiment in comparison.

FIG. 3 is a sectional front view showing another embodiment of the synthetic resin pipe joint of the present invention.

FIG. 4 is a cross-sectional front view showing an example of a conventional synthetic resin pipe joint.

FIG. 5 is a side view of the same.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Branch pipe joint, 11 ... Straight tubular main body part, 12 ... Main pipe connection port, 13 ... Branch pipe connection port, 14 ... Small diameter section, 15 ... Pipe, 16 ... Stopper, 17 ... Branch section Inside part, 18 ... Branch outside part, 21 ... Step inside branch part, 22 ... Step outside part, 23 ... Step around side part, 30 ... Elbow, 31 ... Inside part of bent part, 32 ... Bend Step in inner part, 33 ... Outer part of bent part, 34 ... Step in outer part of bent part

Claims (2)

[Claims] 1. A synthetic resin pipe joint having a branch portion and a bent portion such as a cheese and an elbow, the branch portion and the bent portion of a connecting pipe end contact stopper provided at a deep portion of a receiving port of the joint. Wherein the step at the inner portion of the pipe is formed higher than the step at the outer portion of the branch portion and the bent portion. 2. The synthetic resin according to claim 1, wherein the step at the inner portion of the branch portion and the bent portion has a height not more than four times the step at the outer portion of the branch portion and the bent portion. Pipe fittings.