JPH07243564A - Pipe fitting - Google Patents

Abstract

PURPOSE:To facilitate checking of the end of nut fastening work with no use of a special tool and enhance the easiness in operations by installing a resin spacer between a major diameter portion of a pipe fitting body and a nut. CONSTITUTION:A nut 5 is engaged by a pipe fitting body 1, and a resin spacer 8 is pinched by this nut 5 and a major diametric portion of the pipe fitting body 1. The end position of the nut fastening is located where the end faces 8A, 8B of the resin spacer 8 whose inside and outside circumferences are in concentrical circles, contact the surface 1A of the fitting body and the end face 5A of the nut, respectively. As simplified procedure, the driving work of the nut 5 is ended upon checking that the spacer 8 does not rotate despite a try to turn it with a finger. Even in case the nut drive has overshot over the fastening end position, the spacer 8 deforms to absorb the excess in driving so as to admit spaciously the rage of the nut fastening end position. This allows any unskilled person to perform the tightening works certainly and easily.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called bite type pipe joint having a tapered intermediate member between a nut and a joint main body which constitutes a seal portion between the outer surface of the pipe and the joint main body. is there.

[0002]

2. Description of the Related Art Conventionally, JIS B 2351 shown in FIG. 7 has been used as a pipe joint having an intermediate member between a nut outer surface and a joint main body that constitutes a seal portion between the outer surface of the pipe and the joint main body.
The bite-in type pipe joint described in (1) and the configuration shown in FIGS. 8 and 9 are known. In FIG. 7, reference numeral 1 is a joint main body, a pipe 6 is inserted into the joint main body 1, a sleeve 2 is placed between a nut 5 and the joint main body 1, and the nut 5 is screwed in, so that the nut 5 is 2 is pressed to form the seal portions 10 and 11. 8 and 9, the pipe 6 is inserted into the joint body 1, the front ferrule 3 and the back ferrule 4 are placed between the nut 5 and the joint body 1, and the nut 5 is screwed into the nut 5 to make the nut 5 The back ferrule 4 presses the back ferrule 4 against the front ferrule 3 to form seal portions 12 and 13. Further, in FIG. 9, in order to prevent the nut 5 from being screwed excessively, the metal spacer 7 is provided with the nut 5
It is arranged between the joint body 1 and the nut 5 as a stopper.

[0003]

However, as shown in FIG.
In this type of pipe joint shown in FIG. 8, the tightening degree of the nut 5 has a great influence on the sealing property, and therefore the end of tightening is controlled by the rotation angle of the nut 5, and the nut 5 is tightened until it cannot be rotated by fingers. For example, the tightening tool such as a wrench is used to complete the tightening of the nut 5 by visually detecting that it has been rotated about 1 and 1/4 times or by an angle detecting means. There is a problem that it is impossible or no angle detecting means can be provided.

In the configuration of FIG. 9, the end of tightening the nut 5 is detected by rotating the metal spacer 7 with a finger so that the nut 5 does not rotate. Before confirming that the metal spacer 7 does not rotate, the nut is detected. When 5 is tightened too much and an excessive load is applied to the screw part to damage it, or when it is rotated with adjustment so that it does not rotate too much, it is necessary to check that the metal spacer 7 does not rotate several times. There was a problem of poor sex.

[0005]

The present invention has been invented to solve these problems, and a seal portion is formed between a nut and a joint body, and between a pipe outer surface and the joint body. In the pipe joint including the intermediate member, a resin spacer is arranged between the joint body and the nut.

[0006]

In the above pipe joint, when the both ends of the resin spacer come into contact with the joint body and the nut and the spacer does not rotate by turning with the fingers, the nut tightening end position is set.
Even if you turn the nut too much past the tightening end position with a tightening tool such as a wrench, the nut presses the resin spacer and deforms it, so excessive stress does not occur in the screw part and the nut does not damage the joint member. The tightening work of can be completed. This is as shown in the relationship of the actually measured values in FIG. 10, and the metal spacers of the curves B and D and the bronze spacer of C have nut rotation angles of 1.4 to 1.
The screw part was damaged during 6 rotations, but the resin spacer D was not damaged even after 2 rotations.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, a threaded portion is provided on the outer periphery of the cylindrical portion, an inner cylindrical portion 1C is provided inside, and an inner cylindrical portion 1C of the joint body 1 having a tapered sealing surface 1B inside the cylindrical end portion is provided.
The tube 6 is inserted in the. A nut 5 having a threaded portion on the inner circumference is loosely fitted to the outer periphery of the pipe 6, and a tapered seal surface 2A forming a seal portion 10 with the seal surface 1B of the joint body 1 and the outer surface of the pipe 6. The sleeve 2, which is an intermediate member having the sealing surface 2B forming the sealing portion 11, is fitted between and, and is fastened at the inner end of the nut 5 and the end of the joint body 1. The nut 5 is screwed to the joint body 1 so that the resin spacer 8 is sandwiched between the large diameter portion of the nut 5 and the joint body 1.

Next, another embodiment will be described with reference to FIG. In FIG. 2, a screw portion is provided on the outer circumference of the cylindrical portion,
The pipe 6 is inserted into the inner cylinder portion 1C of the joint body 1 having the inner cylinder portion 1C on the inner side and the tapered seal surface 1B on the inner side of the cylindrical end portion. A nut 5 having a threaded portion on the inner circumference is loosely fitted to the outer circumference of the pipe 6, and a tapered seal surface 3A forming a seal portion 12 with the seal surface 1B of the joint body 1 and the outer surface of the pipe 6. Sealing surface 3 forming a sealing portion 13 between
The front ferrule 3 that is an intermediate member having B and the back ferrule 4 that presses the front ferrule 3 are fitted together, and are tightened at the inner end of the nut 5 and the end of the joint body 1. The nut 5 is screwed to the joint body 1 so that the resin spacer 8 is held between the nut 5 and the large diameter portion of the joint body 1.

Further, in FIGS. 1 and 2, at the tightening end position of the nut 5, both end surfaces 8A and 8B of the resin spacer 8 whose inner and outer circumferences are concentric are respectively the joint body surface 1.
A, a position where the nut end surface 5A comes into contact. Then, for the sake of simplicity, the resin spacer 8 is rotated with a finger to confirm that the resin spacer 8 does not rotate, and the screwing operation of the nut 5 is completed. Here, even if the nut 5 is screwed in too much from the tightening end position, the resin spacer 8 is deformed to absorb the excessive screwing of the nut 5, and a wide range of the tightening end position of the nut 5 is allowed. There is.

Next, another embodiment of the resin spacer 8 will be described with reference to FIGS. In the embodiment of FIG. 4, the outer shape is an ellipse, and in the embodiment of FIG. 5, a part of the outer shape is an ellipse. This outer shape is not limited to FIGS. If In the embodiment shown in FIG. 6, the joint body 1 can be assembled in the radial direction with a partially opened shape. In the case of FIGS. 4 to 6, both end surfaces 8A, 8B of the resin spacer 8 are respectively the joint body surface 1A,
When contacting the nut end surface 5A, the spacer 8 starts to rotate together with the nut 5 due to the difference in friction torque acting on both end surfaces of the resin spacer 8. Therefore, the rotation of the resin spacer 8 has an external shape that is a non-rotationally symmetric shape. The tightening of the nut 5 can be completed by visually observing the movement in the rotation direction.

[0011]

As described above, by using the resin spacer, the special tool is not required and the completion of tightening the nut can be easily confirmed. Therefore, the workability is improved and the tightening work can be surely performed even by a non-specialist. It will be easy to do. In addition, since it is made of resin, it can be made lighter and less expensive than metal.

[0012]

[Brief description of drawings]

FIG. 1 is a sectional view of a pipe joint showing an embodiment of the present invention.

FIG. 2 is a sectional view of a pipe joint showing another embodiment of the present invention.

FIG. 3 is a plan view of an example of a resin spacer used in the present invention.

[Figure 4]

FIG. 6 is a plan view of another example of the resin spacer used in the present invention.

FIG. 7 is a cross-sectional view of an example of a conventional pipe joint.

[FIG. 8]

FIG. 9 is a cross-sectional view of another example of the conventional pipe joint.

FIG. 10 is a diagram showing the relationship between the rotation angle after the end of hand tightening of the nut and the measured value of the tightening torque when the metal spacer, the bronze spacer of the conventional example, and the resin spacer of the example are used. [Brief Description of Drawings] 1 Joint body 5 Nut 1A Joint body surface 5A Nut end surface 1B Sealing surface 6 Tube 1C Inner tube portion 7 Metal spacer 2 Sleeves 7A, 7B End surface 2A, 2B Sealing surface 8 Resin spacer 3 Front ferrule 8A, 8B End surface 3A, 3B Seal surface 10-13 Seal part 4 Back ferrule

Claims (5)

[Claims] 1. A pipe inserted into a joint body having a threaded portion on the outer periphery of an end portion and a large diameter portion, and a pipe loosely fitted to the outer periphery of the pipe and screwed to the threaded portion of the joint body on the inner periphery. For a bite type pipe joint that is composed of a nut with a threaded portion and a sleeve with a tapered portion that is sandwiched between the joint body end portion on the outer periphery of the pipe and the inner end of the nut and is arranged inside the nut, the diameter of the joint body is large. A pipe joint characterized in that a resin spacer is arranged between the portion and the nut. 2. A pipe inserted into a joint body having a threaded portion on the outer periphery of the end portion and a large diameter portion, and a pipe loosely fitted to the outer periphery of the pipe and screwed to the threaded portion of the joint body on the inner periphery. A pipe joint consisting of a nut with a threaded portion, a front ferrule and a back ferrule that are sandwiched between the outer end of the pipe and the inner end of the joint body and the inner end of the nut, and are located inside the nut. A pipe joint characterized in that a resin spacer is arranged between the portion and the nut. 3. The pipe joint according to claim 1 or 2, wherein the resin spacer has concentric circles on the inner and outer circumferences. 4. The pipe joint according to claim 1, wherein the resin spacer has a circular inner circumference and a non-circular outer circumference. 5. The pipe joint according to claim 3 or claim 4, wherein the resin spacer has a partially opened shape.