JPH0612887U - Pipe fittings - Google Patents

Abstract

(57) [Summary] [Purpose] To firmly fix the pipe to the joint body and obtain a connected state with excellent pull-out resistance. [Structure] Assembling a seal member 3 which is externally fitted to a pipe 1 in a compressed state on an inner circumference of a connecting cylinder 7 provided in a joint body 2,
The collet 5 is arranged between the cap nut 4 and the pipe 1 which are externally fitted and screwed to the connection cylinder 7, and the inner peripheral surface of the end portion of the cap nut 4 and the outer peripheral surface of the collet 5 have a large diameter toward the joint body 2 side. Formed on the tapered surfaces 12 and 13, and the diameter of the collet 5 is reduced by the taper surfaces 12 and 13 by screwing the cap nut 4, and the pipe 1 is tightened by the collet 5 to connect the joint body 2 and the pipe 1. . By tightening the collet 5, a connection with a high withdrawal strength of the pipe 1 can be obtained, and the seal member 3 can provide an airtight and watertight state of the connection portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pipe joint for connecting metal pipes such as stainless steel in an airtight and watertight manner.

[0002]

[Prior art]

 Conventionally, various types of joints have been proposed for connecting stainless steel pipes used as pipes for various fluids.

For example, an end of a pipe is inserted into a connection hole of a joint body, a tightening nut that is externally fitted to the pipe is screwed into the joint main body, and the nut is externally fitted to the pipe between the end of the joint main body and the tightening nut. One of them is that the joint body and the pipe are connected in an airtight and watertight manner by compressing the packing and tightening the outer circumference of the pipe with this packing.

[0004]

[Problems to be solved by the device]

 By the way, in the above pipe joint, the pipe is straight and the pull-out strength of this pipe and the joint body is obtained by the tightening force of the packing, so the strength against the pull-out force in the axial direction of the pipe is high. There is a problem that is weak.

Therefore, in order to solve the above problems, the present invention tightens the outer circumference of the pipe by reducing the diameter of the collet, so that a connection with excellent air-tightness and water-tightness and strong pull-out resistance can be performed. An object is to provide a pipe joint.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention is directed to a fitting main body having a seal member fitted on the inner circumference inserted into the end of the pipe, and a fitting main body fitted to the pipe insertion side of the fitting main body. And a collet that is fitted onto the pipe while being in contact with the pipe insertion side end surface of the joint body, and is located inside the cap nut. The outer peripheral surface of the collet, which corresponds to the inner peripheral surface, is formed as a tapered surface having a large diameter toward the joint body side.

[0007]

[Action]

 With the collet and the cap nut fitted onto the pipe, insert the end of the pipe into the connection hole and screw the cap nut onto the outer periphery of the fitting body while the packing is installed in the connection hole of the fitting body. Then, the collet is pushed in the axial direction by the cap nut and comes into contact with the end face of the fitting body.By tightening the cap nut, the collet is reduced in diameter by the taper surface, the pipe is tightened by its inner peripheral surface, and the joint body is sealed by the seal member. The connection between the pipe and the pipe is made airtight and watertight, and the pullout resistance of the pipe connection is improved due to the retaining effect by tightening the collet.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in the figure, the pipe joint for connecting the stainless steel pipe 1 includes a joint body 2, a seal member 3 incorporated in the inner periphery of the joint body 2, and an outer side of the joint body 2 on the pipe insertion side. It is configured by a combination of a cap nut 4 to be fitted and screwed, and a metal collet 5 arranged inside the cap nut 4.

The joint body 2 is formed by connecting a connecting cylinder 7 of the pipe 1 to one end side of the large-diameter portion 6 having a polygonal shape and a screw cylinder 8 connecting a pipe to the other end side thereof. The inner circumference of the large diameter portion 6 is a connection hole 9 into which the pipe 1 is fitted, and the inner circumference of the connection cylinder 7 is provided with a circumferential groove 10 for incorporating the seal member 3 using an O-ring or the like. Has been.

A screw 11 is formed on the outer peripheral surface of the connecting cylinder 7 and the inner peripheral surface of the cap nut 4, and the cap nut 4 is screwed onto the connecting cylinder 7 from the end on the insertion side of the pipe 1. Will be tightened.

The collet 5 has a cylindrical shape having an inner diameter to be fitted onto the pipe 1 and an outer diameter to be accommodated inside the cap nut 4, and the inner peripheral surface of the end portion of the cap nut 4 and the outer peripheral surface of the collet 5 are on the joint body 2 side. The taper surfaces 12 and 13 are formed on the taper surfaces 12 and 13 having a large diameter toward the end, and the collet 5 is adapted to be contracted by the taper surfaces 12 and 13 when the cap nut 4 is axially moved.

As shown in FIG. 2, the collet 5 is provided with a plurality of slits 14 that end axially in the middle from the ends, and the slits 14 provide the diameter reducing property.

Further, in the case shown in the figure, the inner peripheral surface of the collet 5 is formed in a sawtooth cross-sectional shape, and when the diameter of the collet 5 is reduced, the tip of the tooth bites into the outer peripheral surface of the pipe 1 to prevent pull-out. Although an example of improving the strength is shown, the inner peripheral surface may be a smooth surface. Further, a plurality of sets of recessed notches 16 are provided on one end and the other end of the collet 5 on the large diameter side end face of the collet 5 that abuts against the connection body 7 of the joint body 2, The collet 5 does not rotate together when the cap nut 4 is tightened.

The pipe joint of the present invention has the above-mentioned structure. To connect the joint body 2 and the pipe 1, the seal member 3 is assembled in the groove 10 of the joint body 2 and the collet is attached to the pipe 1. 5 and the cap nut 4 are externally fitted and inserted.

The pipe 1 is inserted into the connection hole 9 of the joint body 2, the seal member 3 is put into a compressed state by the penetration of the pipe 1, and then the collet 5 and the cap nut 4 fitted to the outside thereof are attached to the shaft. Direction, and the cap nut 4 is screwed into the connecting cylinder 7 and tightened.

In the cap nut 4, the tapered surface 12 of the inner circumference of the end is fitted onto the collet 5 and screwed into the connecting cylinder 7 to move the collet 5 in the axial direction. The collet 5 is attached to the end surface of the connecting cylinder 7. Since the cap nut 4 stops in the contacting state, only the cap nut 4 moves axially by screwing, and the movement of the cap nut 4 causes the collet 5 to be reduced in diameter by the action of the tapered surfaces 12 and 13, and the inner peripheral surface thereof. Tighten pipe 1.

By tightening the pipe 1 by reducing the diameter of the collet 5 as described above, the pipe 1 is fixed to the joint body 2 and, as shown in FIG. 1, a connection state having excellent pull-out strength can be obtained. The seal member 3 makes the connecting portion between the joint body 2 and the pipe 1 airtight and watertight.

[0019]

【effect】

 As described above, according to the present invention, the inner peripheral surface of the cap nut that is screwed into the connection tube of the joint body and the outer peripheral surface of the collet that is placed inside the cap nut are formed into tapered surfaces, and the taper is created by screwing the cap nut. Since the diameter of the collet is reduced on the surface, by tightening the pipe by reducing the diameter of the collet, the joint body and the pipe can be firmly connected and a connection with excellent pull-out strength can be made.

In addition, the connecting portion between the joint body and the pipe is airtight and watertight by the seal member.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing a pipe connection state of a pipe joint according to the present invention.

FIG. 2 is a perspective view of a collet used in the above.

[Explanation of symbols]

 1 Pipe 2 Joint Main Body 3 Sealing Member 4 Cap Nut 5 Collet 7 Connection Tube 9 Connection Hole 12, 13 Tapered Surface 14 Slit

Claims (1)

[Scope of utility model registration request] 1. A joint main body in which a seal member externally fitted to the pipe is incorporated into an inner periphery inserted into an end portion of the pipe, and a cap nut externally fitted and screwed to the pipe insertion side of the joint main body. An outer peripheral surface of the collet, which is fitted onto the pipe while being in contact with the end surface of the joint body on the pipe insertion side, and which is a collet located inside the cap nut. Is a pipe joint that has a tapered surface with a large diameter toward the joint body side.