JP2003185076A - Pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe joint in which insufficient insertion of a pipe is surely found. <P>SOLUTION: An O-ring 12 for cut-off of water is disposed inside a joint body 10 of the joint. In the joint, a pressed member 14, which has projection pieces 32 radially formed on the periphery of an annular body 30 of a size capable of passing through the O-ring 12 when the annular body is pressed by a tip of the pipe, is disposed in front of the O-ring 12. In the pressed member 14, when the pipe is inserted to a predetermined position, the projection piece 32 passes through the O-ring 12 with the projection piece 32 bent. On the other hand, when the pipe does not reach the predetermined position, the projection piece 32 is left in the O-ring 12 with the projection piece bent. Therefore, when the insertion of the pipe is insufficient, water will surely leak in a hydraulic test performed after the execution, and thereby the insufficient insertion of the pipe is surely found. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint, and more particularly to a one-touch type pipe joint capable of performing connection processing only by inserting a pipe. 2. Description of the Related Art Pipe fittings are required to have a water stopping performance for suppressing water leakage and the like and a retaining performance for preventing the pipe from being pulled out. By inserting the pipe to a predetermined position, the structure satisfies the required performance described above. Therefore, in order to exhibit the required performance, it is necessary to insert a pipe in a previously designed amount. For this reason, conventionally, a pipe before insertion is applied to a pipe joint, a marking is provided on the surface of the pipe as a guide of the length to be inserted, and the pipe is pushed into the marked position to reduce the insertion amount of the pipe. I was checking. [0004] However, the method of marking a pipe is troublesome when the number of pipes to be connected is large, and since the operator himself performs the marking, the position of the marking may be shifted. This tends to cause variation in the insertion amount. As a result, the water stopping performance becomes incomplete and water leakage may occur. [0005] In view of the above problems, an object of the present invention is to provide a pipe joint that can easily confirm that a pipe has been inserted to a predetermined position after construction. In order to achieve this object, the present invention relates to a pipe joint having an O-ring for stopping water inside a joint body. A pushed member formed with a projecting piece is arranged on the outer periphery of an annular body large enough to be pushed and pass through the O-ring, and when the pipe is inserted to a predetermined position, the projecting piece becomes an O-ring. When the tube is not inserted to a predetermined position while being bent by the O-ring and the tube is not inserted to a predetermined position, the protruding piece is left inside the O-ring in a state bent by the O-ring. With such a configuration, if the pipe is inserted sufficiently, the O-ring comes into close contact with the outer peripheral surface of the pipe, so that no water leakage occurs even when water pressure is applied, and the pipe is not sufficiently inserted. In such a case, a water leakage path is formed along the protruding piece remaining inside the O-ring, so that when water pressure is applied, water leakage can be reliably generated. Therefore, by performing a water pressure test after construction, it is possible to reliably detect insufficient insertion of pipes,
You can take measures against it. Hereinafter, embodiments of the present invention will be described.
This will be described in detail with reference to the drawings. FIG. 1 shows an embodiment of a pipe joint according to the present invention. In the drawing, 10 is a tubular joint body, 12 is an O-ring, 14 is a member to be pushed in, 16 is a washer, 18 is a retaining ring,
Reference numeral 20 denotes a backup ring, reference numeral 22 denotes a cap nut, and reference numeral 24 denotes a pipe joint composed of the above components. [0010] The O-ring 12 is a sealing member that is in close contact with the outer peripheral surface of the inserted pipe to obtain water stopping performance. The retaining ring 18 is a retaining member for preventing the inserted tube from being pulled out. The retaining ring 18 is provided with a metal blade 26 that cuts into the outer peripheral surface of the pipe on the inner peripheral surface, has a split 28 in a part in the circumferential direction, has spring elasticity, and has a larger diameter. The diameter can be reduced. The retaining ring 18 has an inner diameter slightly smaller than the outer diameter of the tube in a released state (a state in which no external force is applied), and when the tube is inserted, it is expanded and pressed against the outer peripheral surface of the tube. Thereafter, when a pulling force is applied to the tube, the retaining ring 18 tries to retreat together with the tube, but the stopper ring 18 comes into contact with the tapered surface 20a of the backup ring 20 and is prevented from retreating.
26 cuts into the outer peripheral surface of the tube to prevent the tube from being pulled out. [0012] Among the components incorporated in the joint body 10, the components other than the pushed-in member 14 are the same as those used in a conventional pipe joint. A feature of the pipe joint 24 is that the pushed-in member 14 is arranged in front of the O-ring 16 in the joint main body 10. As shown in FIG. 2, the pushed member 24 has an annular body 30 sized to be pushed by the tip of the tube and able to pass through the O-ring 16, and a plurality of protruding pieces 32 are radially formed on the outer periphery thereof. Things. It is preferable that the plurality of projecting pieces 32 are formed at substantially equal intervals in the circumferential direction. The strength of the protruding piece 32 is set to such a degree that the protruding piece 32 bends (falls) backward when the annular body 30 is pushed into the O-ring 16. FIG. 3 shows a state in which the pipe P has been inserted into the above-mentioned pipe joint 24 to a predetermined position. When the pipe P is sufficiently inserted in this manner, the pushed member 14 passes through the O-ring 16 while the protruding piece 32 is bent backward. As a result, the O-ring 16 comes into close contact with the outer peripheral surface of the pipe P, and sufficient water stopping performance can be obtained. In this state, even if the pipe P is slightly retracted due to a pulling force applied to the pipe P, no water leakage occurs. FIG. 4 shows a state in which the pipe P has not been inserted into the pipe joint 24 to a predetermined position. When the insertion of the pipe P ends in an insufficient manner, the O-ring 16 is bent in a state where the protruding piece 32 of the pushed-in member 14 is bent backward.
Will remain inside. For this reason, a water leak path is formed between the pipe P and the O-ring 16 along the protruding piece 32, and when water pressure is applied to the inside of the pipe, the water leak will surely occur. Therefore, by performing a water pressure test after the construction, it is possible to reliably detect the insufficient insertion of the pipe, and to take measures against it. In a conventional pipe joint having no member to be pushed in, if the pipe P is pushed into the position shown in FIG. 4, no water leakage occurs in the hydraulic test after the construction, and the pipe passes. If, for some reason, a pulling force is applied to the pipe (for example, after delivery of the equipment), the pipe will be slightly retracted, and water leakage will occur. Therefore, it has been difficult for the conventional pipe joint to detect insufficient insertion of the pipe. As described above, in the pipe joint of the present invention, if the pipe is not inserted to a predetermined position, water leakage will surely occur in a water pressure test after construction, Insertion shortage can be reliably detected. Therefore, it is possible to reliably take measures against it. In addition, if no water leak is found in the water pressure test after the construction, it is possible to guarantee that the construction is complete and to improve the reliability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing an embodiment of a pipe joint according to the present invention. FIG. 2 is a perspective view of a pushed member used for the pipe joint of FIG.
(A) is a front view, (B) is a half-cut side view. FIG. 3 is a cross-sectional view showing a state where a pipe has been inserted to a predetermined position in the pipe joint of FIG. 1; FIG. 4 is a cross-sectional view showing a state where a pipe has not been inserted to a predetermined position in the pipe joint of FIG. 1; [Description of Signs] 10: Joint body 12: O-ring 14: Pushed member 18: Retaining ring 22: Cap nut 24: Pipe joint 30: Annular body 32: Protrusion piece P: Pipe

Continuation of front page    (72) Inventor Takashi Sato             2-6-1 Marunouchi, Chiyoda-ku, Tokyo Old             Kawa Electric Industry Co., Ltd. F-term (reference) 3H014 GA07                 3H019 HA01                 3J106 AB01 BC04 BD01 BE26 EC01                       ED08 EE04

Claims (1)

Claims: 1. A pipe joint having an O-ring (12) for stopping water inside a joint body (10), wherein the O-ring (12) is provided.
A member to be pushed (14) having a protruding piece (32) formed on the outer periphery of an annular body (30) large enough to pass through the O-ring (12) by being pushed by the tip of the pipe (P) is arranged in front of. When the pipe (P) is inserted to a predetermined position, the pushed member (14)
When the protruding piece (32) is bent by the O-ring (12) and passes through the O-ring (12) and the pipe is not inserted to a predetermined position, the protruding piece (32) is bent by the O-ring (12). A pipe joint characterized by being left inside an O-ring (12).