JP2535792Y2 - Buried pipe fittings - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint for a buried pipe, and more particularly, to a buried pipe for connecting a pipe by fastening a biting member to the outer periphery of the pipe by fastening a fastener to the joint body. The present invention relates to a pipe joint.

[0002]

2. Description of the Related Art Buried pipes used for water supply pipes and the like are:
Considering the weight of the car running on the ground or the case where it receives an external force such as land subsidence, the angle of the joint can be slightly changed, and it can expand and contract in the axial direction by sliding relative to the joint. It has become.

Conventionally, various types of such joints for buried pipes have been provided, but they have a relatively large number of parts and have problems such as loss of parts, prolonged assembly work, and incorrect work procedures. There were many.

The applicant has proposed a buried pipe joint disclosed in Japanese Utility Model Publication No. 3-34543 in order to solve these problems.

This joint has a joint body having a hole into which a pipe to be connected is inserted, a threaded portion to be screwed to an end of the joint body, and a diameter gradually increasing toward the threaded portion. A fastening member having an inner peripheral wall, a lock ring in contact with the inner peripheral wall of the fastening member, and a biting member cooperating with the lock ring. The biting member is formed by screwing the fastening member to the joint body. Is connected to the pipe and the joint by making the outer periphery of the pipe bite through the lock ring,
The lock ring forms a substantially V-shape from one end of the annular portion radially outward from one end of the annular portion at a position corresponding to the position of the through hole in the circumferential direction with the annular portion provided with a plurality of through holes. The biting member comprises a plurality of bent portions, and the biting member is formed in such a manner that a part of the biting member projects from each through hole of the ring portion of the lock ring into the inside of the ring portion, and It is sandwiched between each bent part. Then, when the fastening member is screwed into the joint body, the inclined inner peripheral wall of the fastening member comes into contact with the bent portion of the lock ring, and the lock ring is gradually reduced in diameter, and the biting member is attached to the outer periphery of the pipe through the bent portion. It is designed to press and bite.

In the above-mentioned joint, since the lock ring and the biting member are integrally assembled,
It is easy to handle and very effective in solving the above-mentioned problems of the conventional example.

[0007]

However, in the above-mentioned joint, when a pulling force is applied to the connected pipe, sometimes the biting member is moved by the movement of the pipe due to the presence of the lock ring. Variations occur to such an extent that they can be moved to the small diameter side of the inner wall, and as a result, variations occur in the tube pull-out preventing force.

In order to prevent such variation, as shown in FIG. 1 of Japanese Utility Model Publication No. 3-34543, a groove is formed on the outer periphery of the inserted tube, and a biting member is bitten in the groove. This is effective.

[0009] However, forming a groove on the outer periphery of the tube is a troublesome operation, and it is necessary to confirm that the biting member has been fitted into the groove when inserting the tube. Therefore, from the viewpoint of simplification of the operation and cost reduction, it is desirable that sufficient escape prevention can be obtained without forming a groove in the pipe.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and is disclosed in Japanese Utility Model Publication No. 3-3454.
In the joint as shown in No. 3, the through hole formed in the annular portion of the lock ring is an elongated hole in the axial direction, and the biting member partially projects into the annular portion. In such a manner as to be movable between the bent portion and the annular portion.

[0011]

Therefore, when a pulling force acts on the pipe, the biting member moves along the elongated hole to the small diameter side of the inner wall of the fastening member along the elongated hole as the pipe moves, and the biting member bites into the pipe. The cost increases, and the tube is surely prevented from coming out.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an upper half sectional view showing a state in which a buried pipe joint 10 according to an embodiment of the present invention is temporarily assembled as a set, and the buried pipe 2 is about to be inserted into the joint 10.

The joint 10 includes a joint body 12 and a cap nut 1 as a fastening member combined with the joint body 12.
8 is provided. The joint body 12 is provided with a central hole 13 for receiving the buried pipe 2 therein and a male screw 15 on the outer peripheral portion of the distal end. Further, the inner diameter of the distal end is gradually increased in diameter toward the distal end, and a packing accommodating portion 14 for accommodating a packing 22 for sealing between the pipe 2 and the joint body 12 is provided. The cap nut 18 is provided on the inner periphery of the distal end side of the main body 1.
A female screw 19 to be screwed to the second male screw 15 is formed, and an inclined inner peripheral wall 20 whose diameter is gradually increased toward the male screw 15 is formed. Further, an annular groove for accommodating a cup seal 24 for sealing between the cap nut 18 and the pipe 2 is formed on an inner periphery of the rear end.

Reference numeral 26 denotes a washer for compressing the packing 22, and reference numeral 28 denotes an O-ring.

Reference numeral 30 denotes a plurality of balls 3 as biting members.
6 is a lock ring that holds the lock ring 6 in detail.
Is shown in FIG.

The lock ring 30 in this embodiment is a fourth type.
As shown in FIGS. 5 and 5, the annular portion 31 and the annular portion 3
It is formed of a plurality of bent portions 33 which are continuous with one end of the first portion and are separated from each other by cuts 32, and which are further bent radially outward so as to form a substantially V shape. A plurality of elongated through holes 34 extending in the axial direction are provided in the annular portion 31 at intervals in the circumferential direction. The through-holes 34 and the bent portions 33 are arranged so as to correspond to each other in the circumferential direction of the ring. A ball 4 having a diameter larger than the width of the through-hole is fitted into each of the through-holes from the outside of the annular portion 31, and a part of the ball 4 is set to protrude into the inside of the annular portion 31. . Ball 36
Even in the position shown by the two-dot chain line in FIG. 5, the width of the elongated hole 34 of the ball 36 and the bent portion 33 are set so that the ball 36 is prevented from being detached from the elongated hole 34 by each bent portion 33. Is defined. Therefore,
The ball 36 can move along the elongated hole 34, but does not come off the lock ring 30. Note that the lock ring 30 in the present embodiment has a split 35 in a part of the annular portion 31.

When the buried pipe 2 is inserted into the joint 10 by a predetermined dimension from the state shown in FIG. 1, the ball 36 is pushed leftward in FIG. 1 along the elongated hole 34 and is placed on the outer periphery of the pipe 2. Then, when the cap nut 18 is tightened, the nut 18
Of the bent portion 3 of the lock ring 30
Since the ball 3 is pressed, the ball 36 is firmly pressed on the outer periphery of the tube 2 and fixes the tube 2 and the joint 10.
This state is shown in FIG. In this state, the ball 36 comes into contact with the tip 35 of the elongated hole 34 and does not advance any further.

When the pipe 2 is buried in this state, a force acts to pull out the pipe 2 from the joint 10, and this force is applied to the pipe 2 as shown in FIG.
If it is larger than the fixing force due to the biting of the ball 36 in the above, the tube 2 moves to the left as shown in FIG. At this time, the ball 36 also rolls along the elongated hole 34 from the position indicated by the two-dot chain line in FIG. 3 to the position indicated by the solid line. Along with this, the ball 36 is further moved radially inward by the bent portion 33 of the lock ring 30 which is in close contact with the inclined peripheral inner wall 20 of the nut 18, and the biting allowance on the pipe 2 increases, and the fixing force is increased. To prevent the tube 2 from slipping out.

[0020]

As described above, in the joint for a buried pipe according to the present invention, the hole of the lock ring for holding the biting member is a long hole in the axial direction, and the buried pipe tends to fall out of the joint. Then, the biting member is also moved in the radial direction and at the same time as the biting member is moved in the axial direction, so that the biting allowance for the pipe 2 is increased and the pipe is prevented from coming off. Therefore,
A sufficiently large and stable fixing force can be obtained without forming an outer peripheral groove for receiving the inner portion of the biting member and increasing the fixing force in the buried pipe. Therefore, it is not necessary to form an outer peripheral groove in the buried pipe, and it is not necessary to confirm the fitting of the biting member into the groove when the pipe is inserted, so that the operation can be simplified and the cost can be reduced.

[0021]

[Brief description of the drawings]

[0022]

FIG. 1 is a half sectional view showing a temporarily assembled state of the joint of the present invention.

[0023]

FIG. 2 is a half sectional view showing a state where a buried pipe is fastened to a joint.

[0024]

FIG. 3 is a half sectional view showing a state when a pulling force acts on a buried pipe.

[0025]

FIG. 4 is a front view showing an assembled state of a lock ring and a ball.

[0026]

FIG. 5 is a sectional view taken along line 5-5 in FIG. 4;

[0027]

[Explanation of symbols]

2 Buried pipe 10 Joint 12 Joint main body 18 Cap nut 30 Lock ring 31 Ring part 33 Bend part 34 Slot hole 36 Ball

Claims (1)

(57) [Scope of request for utility model registration] 1. A joint body having a hole into which a pipe to be connected is inserted, a threaded portion screwed to an end of the joint body, and a slope gradually increasing in diameter toward the threaded portion. A fastening member having an inner peripheral wall, a lock ring in contact with the inner peripheral wall, and a biting member cooperating with the lock ring, wherein the biting member is screwed into the joint body to fasten the biting member. In a joint for a buried pipe in which a pipe and a joint are connected by being pierced to the outer periphery of the pipe via a lock ring, the lock ring has a plurality of through-holes extending in an axial direction and separated in a circumferential direction. The provided annular portion, and a plurality of bent portions bent in a radial direction from one end of the annular portion at a position corresponding to the position of the elongated through hole in the circumferential direction. Wherein the biting member has a length corresponding to each penetration length of the annular portion. A part of the biting member projects from the hole into the inside of the annular portion, and is held between the annular portion and each of the bent portions so as to be movable along the elongated through hole, and the joint body When the fastening member is screwed in, the inclined inner peripheral wall of the fastening member comes into contact with the bent portion of the lock ring, and gradually reduces the diameter of the lock ring, and the biting member is moved through the bent portion. A joint for a buried pipe, which is pressed against the outer circumference of the pipe to make it bite.