JP2945653B1 - Lock ring - Google Patents

Abstract

An object of the present invention is to secure a required amount of a restricting piece into a resin pipe inserted into a joint to prevent the pipe from falling out of the joint, and to restrict a bite amount of the pipe. Provided is a lock ring capable of preventing damage to the lock ring. A lock ring includes a base ring formed in an annular shape and a plurality of restricting pieces projecting inward from the base ring at the same length. Each restricting piece 36 has a distal end portion formed in an arc shape. The notch 39 is formed in the center between a pair of adjacent restriction pieces 36 in an arc shape so as to have a predetermined depth from the restriction piece 36 side to the base ring 35 side.
The slit 40 is formed from the center of the bottom of the notch 39 to the base ring 35 so as to correspond to the depth at which the regulating piece 36 bites into the pipe 11. At this time, the base ends of the pair of adjacent restriction pieces 36 are connected via the slit 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock ring for preventing an end of a resin pipe used for water pipes, hot water pipes, floor heating, road heating, etc. from coming out of a joint. .

[0002]

2. Description of the Related Art A conventional lock ring is disclosed in Japanese Patent No. 26851.
A pipe joint disclosed in Japanese Patent Publication No. 05-2005 is known. The pipe joint is formed into a cylindrical shape, a socket that allows insertion of a pipe, a lock ring, a backup ring, and a seal ring that are disposed in an enlarged inner diameter portion provided therein, and are screwed to the outer periphery of the socket, And a cap for preventing each ring from coming out of the pipe joint.

The lock ring includes an annular base ring and a plurality of restricting pieces projecting from the base ring at predetermined intervals in the circumferential direction. Also,
A claw of a predetermined length is formed at the tip of each regulating piece so as to protrude inward, and at both sides of the regulating piece, a protruding portion is formed which projects in the width direction of the regulating piece.

When a pipe is inserted into a joint,
The required amount of the locking ring claw bites into the pipe to prevent the pipe from slipping out of the pipe joint, and prevents the claw from penetrating the claw by the projection to prevent the claw from penetrating the pipe wall. To prevent it.

[0005]

However, when an external force is applied in the direction in which the pipe is pulled out, the protrusion formed on the restricting piece alone can prevent the nail from biting into the pipe beyond a required amount. Did not. Also, when the amount of biting of the restricting piece gradually increases as the external force in the pulling direction increases, a tear may be formed on the pipe wall. For this reason, there has been a problem in that the pipe is cut due to the tear, or the regulating piece penetrates the pipe wall, and the transport fluid leaks from that portion.

Further, the concave portion formed between the restriction pieces reaches the base ring, and the claw and the corner of the projection of the restriction piece are sharp. Therefore, when an external force acts in the direction in which the pipe is pulled out, not only does the restricting piece dig into the pipe by a required amount, but also there is a problem that the bite is promoted by the corners of the claws and the protrusions.

The present invention has been made by paying attention to such problems existing in the prior art. The purpose is to secure the required amount of the restricting piece into the resin pipe inserted into the joint, prevent the pipe from falling out of the joint, and restrict the amount of bite. An object of the present invention is to provide a lock ring that can prevent a pipe from being cut.

[0008]

In order to achieve the above object, a lock ring according to claim 1 is engaged with an annular receiving surface provided in a cylindrical joint body. The male body of the cylindrical pressing body is positioned and fixed by the pressing body in the joint formed by screwing the male screw part of the cylindrical pressing body into the female screw part formed in the joint body, and a resin pipe is provided in the joint body via the pressing body. A lock ring that prevents the end of the pipe from coming off the joint when it is inserted until it comes into contact with the abutment surface, and is substantially the same as the base ring engaged with the receiving surface and inward from the base ring. A plurality of regulating pieces projecting in length are provided, and the tip of each regulating piece is formed in an arc shape . Further, between the regulating pieces, the tip of the regulating piece is a pipe.
Notch is formed to correspond to the depth of biting into
The pipe is inserted from the notch to the base ring.
Form a slit to allow deformation of the regulating piece when
It was done.

According to a second aspect of the present invention, in the lock ring according to the first aspect, a notch is provided between the distal end of the restricting piece and the notch.
The shape of the inner bottom portion of the portion is formed in substantially the same arc shape .

[0010]

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. (First Embodiment) As shown in FIG. 1 and FIG.
1 is formed in a cylindrical shape from crosslinked polyethylene or polybutene, and is used for water supply piping and the like. Joint body 12
Is formed in a cylindrical shape from brass or bronze, a first male screw portion 13 is formed at one end outer periphery, and a pipe 1 such as a water supply pipe is formed.
0 can be screwed. The nut part 14 is the joint body 1
2 is formed on the outer periphery of the other end. And the joint body 12
When the thread 10 and the pipe 10 such as a water supply pipe are screwed and released, the joint body 12 can be easily rotated by engaging a wrench or the like with the nut portion 14.

The first female screw portion 15 is formed on the inner circumference at the other end of the joint main body 12. The contact surface 16 is provided on the joint body 12.
An annular portion is provided in the inner back portion so as to be orthogonal to the axis of the joint body 12. The inclined surface 17 is formed in a ring shape in the joint body 12 so that the inner diameter increases from the outer edge of the inner peripheral surface connected to the contact surface 16 toward the first female screw portion 15. The receiving surface 18 is provided on the outer peripheral edge of the inclined surface 17 so as to be orthogonal to the axis of the joint body 12.
2 is formed in an annular shape.

The pressing body 19 includes a cylindrical portion 20 made of brass or bronze, and a grip portion 21 formed smaller than the outer shape of the nut portion 14 of the joint body 12. The second male screw part 22 is formed on the outer peripheral surface of the cylindrical part 20 and can be screwed to the first female screw part 15 of the joint body 12. The pair of locking portions 23 are
Are cut out at opposing positions on the outer periphery of the end.
When the pressing body 19 is screwed into the joint body 12 and released, the pressing body 19 can be easily rotated by engaging a wrench or the like with the locking portion 23. .

The outer peripheral groove 24 is formed in the center of the outer peripheral surface of the pressing body 19, and a first seal ring 25 formed in a ring shape by rubber is fitted in the outer peripheral groove 24 as a seal member. Then, when the pressing body 19 is screwed into the joint body 12, the first seal ring 25 is connected to the pressing body 19 and the joint body 1.
2 is sealed. The first inner circumferential groove 26 is formed slightly closer to the grip 21 than the inner circumferential center of the pressing body 19, and a second seal ring 27 having a circular cross section as a seal member is fitted therein. The second inner peripheral groove 28 is formed closer to the cylindrical portion 20 than the first inner peripheral groove 26, and the third inner seal ring 2 as a seal member is formed there.
9 is fitted.

The third seal ring 29 is an annular rubber packing having a U-shaped cross section. When the pressing body 19 is screwed into the joint body 12, the opening 29a faces the joint body 12. Is fitted. Therefore, even if the liquid leaks, the third seal ring 29
The liquid is accommodated in the accommodating groove 29b from the opening 29a, and the sealing force is increased, so that the liquid can be prevented from leaking out of the joint body 12 and the pressing body 19. Also, when the pipe 11 is inserted from the grip 21 side, the third
The seal ring 29 allows the pipe 11 to be easily inserted into the joint body 12.

As a result, when the pipe 11 is inserted into the joint main body 12 through the pressing body 19, the gap between the pipe 11 and the pressing body 19 is sealed by the second seal ring 27 and the third seal ring 29. It has become.

As shown in FIG. 3, the core ring 30 includes a cylindrical portion 31 made of brass or bronze, and a flange portion 32 formed at one end thereof. The annular portion 42 is formed in an annular shape from the inner end surface 32a of the flange portion 32 to the outer end surface 32b. The chamfered portion 43 is formed so as to decrease in diameter from the outer edge of the annular portion 42 toward the outside. At this time, the core ring 30 extends from the outer edge of the annular portion 42.
When the straight line L extending in the axial direction is assumed, the angle θ between the straight line L and the outer periphery of the chamfered portion 43 is set to 30 degrees. The ratio of the length of the annular portion 42 in the axial direction of the coring 30 to the length of the chamfered portion 43 is set to 1: 2.

As shown in FIG. 5, the tubular portion 31 is
It is designed to fit inside. At this time, the inner end surface 32 a of the flange 32 engages with the end surface 11 a of the pipe 11. Further, when the pipe 11 is inserted into the joint body 12 in this state, the flange 32 can be smoothly inserted without being hooked on the second seal ring 27 and the third seal ring 29 by the chamfered portion 43. It has become. Further, the outer end surface 32 b of the flange portion 32 comes into contact with the contact surface 16 in the joint body 12. At this time, since the outer end face 32b is formed in a flat shape, the contact face 16
The seal function can be demonstrated closely.

The tubular portion 31 is fitted into the pipe 11 to prevent the pipe 11 from being deformed inward due to thermal expansion or the like. As shown in FIG. 1, the end of the pipe 11 in which the core ring 30 is fitted is inserted into the joint body 12 through the press body 19, and the outer end surface 32 of the flange 32 is
When “b” is brought into contact with the contact surface 16 in the joint main body 12, the cylindrical portion 31 projects from the end surface of the pressing body 19 by a predetermined length. Therefore, by visually checking the protruding length, it is possible to confirm whether or not the outer end surface 32b of the flange portion 32 is in contact with the contact surface 16 in the joint body 12. The inclined portion 33 is formed at the other end of the cylindrical portion 31 and is formed so that the outer diameter thereof is reduced toward the other end. Then, the tubular portion 31 is easily inserted into the pipe 11.

As shown in FIGS. 4A and 4B, the lock ring 34 is set to have a thickness of 0.2 to 0.6 mm in order to maintain a predetermined strength. More preferably, it is more preferably set in the range of 0.3 to 0.5 mm. The lock ring 34 is made of stainless steel, and has a base ring 35 formed in an annular shape.
It comprises a plurality of restricting pieces 36 projecting inward from the base ring 35 by the same length. Each regulation piece 36
The tip of the base ring 35 is formed in an arc shape, and the inner peripheral edge of the base ring 35
It is bent to extend in degrees. Then, the pipe 11 is easily inserted from the proximal end side to the distal end side of the restricting piece 36, and the inserted pipe 11 is restricted from coming off.

The notch 39 is formed with a pair of adjacent regulating pieces 36.
An arc-shaped notch is formed in the center between the restricting pieces 36 and the base ring 35 so as to correspond to the depth at which the restricting pieces 36 bite into the pipe 11. Notch 39
Is set such that the pipe 11 can be prevented from coming off when the portion from the tip of the regulating piece 36 to the bottom of the cutout portion 39 bites into the pipe 11.

The slit 40 has a predetermined depth from the center of the bottom of the notch 39 to the base ring 35, that is, when the pipe 11 is inserted into the lock ring 34,
6 is formed to a depth that allows deformation. At this time, the base ends of the pair of adjacent regulating pieces 36 are slits 40.
Are connected via Therefore, the notch 39 is shallower than the recesses 41 formed on both sides of the pair of adjacent restriction pieces 36.

As shown in FIG. 1, the base ring 35 is engaged on the receiving surface 18 of the joint body 12, and the restricting piece 36 is positioned so as to have a gap with the inclined surface 17. When the pressing body 19 is screwed into the joint body 12, the distal end of the cylindrical portion 20 of the pressing body 19 positions and fixes the base ring 35. Therefore, it is possible to prevent the lock ring 34 from moving in the axial direction and the circumferential direction.

Further, the end of the pipe 11 is
When inserted in 4, the restricting piece 36 spreads slightly outward and cuts into the outer periphery of the pipe 11 by a required amount from the tip to the notch 39. At this time, since the slits 40 are formed between the pair of adjacent restriction pieces 36, the outward expansion of the restriction pieces 36 is facilitated. As a result, the pipe 11 is prevented from falling off by the joint body 12.

At this time, since the tip of the regulating piece 36 is formed in an arc shape, the area of the regulating piece 36 biting into the pipe 11 can be reduced, and the shearing force can be prevented. Also, a pair of adjacent restriction pieces 3
A notch 39 formed shallower than the concave portion 41 is formed between the six. Therefore, it is possible to prevent the restriction piece 36 from biting into the pipe 11 to the root and prevent the tear formed by the biting from being connected.

A joint 37 is constituted by the joint body 12, the lock ring 34, the core ring 30, the pressing body 19 and the like. Next, a method of connecting the pipe 11 to the joint 37 will be described.

First, the first male screw portion 13 of the joint body 12 is screwed into the pipe 10 such as a water supply pipe, and the nut portion 14 is screwed by a spanner or the like, and the joint body 12 is fastened and fixed to the pipe 10. Next, the lock ring 34 is inserted into the joint body 12.
And the base ring 35 is engaged with the receiving surface 18 in the joint body 12, and the regulating piece 36 is attached to the inclined surface 1.
7 is provided. And the pressing body 1
9 is screwed into the first female threaded portion 15 of the joint body 12, a wrench or the like is engaged with the engaging portion 23, and the pressing body 19 is screwed into the joint body 12. At this time, the lock ring 34 is positioned and fixed immovably in the axial and circumferential directions by the distal end portion of the cylindrical portion 20 of the pressing body 19, and the gap between the joint body 12 and the pressing body 19 is fixed by the first seal ring 25. Is sealed.

Subsequently, as shown in FIG.
0, the cylindrical portion 31 is fitted into the pipe 11 from the inclined portion 33, and the inner end surface 32a of the flange portion 32 is connected to the end surface 11a of the pipe 11.
Push until it engages. At this time, the chamfered portion 43 allows the flange portion 32 to be smoothly inserted without being caught by the second seal ring 27 and the third seal ring 29.

Then, as shown in FIG.
The end of the pipe 11 on the side where 0 is fitted is inserted into the joint body 12 via the pressing body 19. At this time, the cylindrical portion 31 of the core ring 30 protruding from the other end of the joint body 12
The pipe 11 is pushed in until the projection length of the flange portion 32 becomes a predetermined length, and the outer end surface 32 b of the flange portion 32 is brought into contact with the contact surface 16 in the joint body 12. As a result, as shown in FIG. 1, the gap between the pipe 11 and the pressing body 19 is sealed by the second seal ring 27 and the third seal ring 29, and the end of the pipe 11 is airtight to the joint 37. Connected to. Further, the pipe 11 is prevented from falling out of the joint 37 by the lock ring 34.

As described above, according to the first embodiment, the following effects are exhibited. -According to the lock ring 34 of 1st Embodiment, the front-end | tip part of each control piece 36 is formed in arc shape. Therefore, when the end of the pipe 11 is inserted into the joint body 12 via the pressing body 19, and each of the restriction pieces 36 is cut into the pipe 11, the biting area of the restriction piece 36 into the pipe 11 is reduced. And a shear force can be prevented. Therefore, it is possible to prevent a tear from being formed due to biting, thereby preventing the pipe 11 from being cut.

According to the lock ring 34 of the first embodiment, the depth of the notch 39 is set so as to correspond to the depth at which the tip of the restriction piece 36 bites into the pipe 11. Therefore, the restriction piece 36 can be made to bite into the pipe 11 by a required amount, and the pipe 11 can be reliably prevented from falling out of the joint 37.

According to the lock ring 34 of the first embodiment, the notch 39 formed shallower than the recess 41 is formed between the pair of adjacent restriction pieces 36. for that reason,
The restriction piece 36 can be prevented from biting into the pipe 11 to its root, and the cutting of the pipe 11 can be prevented.

According to the lock ring 34 of the first embodiment, the slit 40 is formed between the pair of adjacent restriction pieces 36. Therefore, when the end of the pipe 11 is inserted into the lock ring 34, the restriction piece 36 is allowed to spread outward, and the pipe 11 can be easily inserted. In addition, the width of the base end of each restriction piece 36 can be secured to maintain its strength.

According to the lock ring 34 of the first embodiment, the base ends of the pair of adjacent restriction pieces 36
Are connected via Therefore, when an external force acts in the pulling direction of the pipe 11, the restricting piece 36 can be prevented from bending in the pulling direction of the pipe 11. Therefore, the contact surface 16 in the joint main body 12 and the outer end surface 32b of the flange 32 of the core ring 30 are kept in close contact with each other, so that good sealing performance can be secured.

According to the lock ring 34 of the first embodiment, the base ring 3 extends from the inner peripheral edge of the base ring 35.
A plurality of restricting pieces 36 are formed by bending so as to extend at 45 degrees with respect to 5. Therefore, the pipe 11 can be easily inserted from the proximal end side to the distal end side of the restriction piece 36, and the inserted pipe 11 can be prevented from coming off from the joint 37.

According to the lock ring 34 of the first embodiment, the base ring 35 of the lock ring 34 is engaged with the receiving surface 18 in the joint body 12, and the distal end of the cylindrical portion 20 of the pressing body 19. Is positioned and fixed. for that reason,
The pipe 1 engaged with the lock ring 34 can prevent the lock ring 34 from moving in the axial direction and the circumferential direction.
1 can be reliably prevented from falling off.

According to the lock ring 34 of the first embodiment, when the lock ring 34 is fitted into the joint body 12, a gap is formed between the restricting piece 36 and the inclined surface 17 in the joint body 12. . Therefore, when the pipe 11 is inserted into the lock ring 34, the regulating piece 36 expands outward, and the pipe 11 can be easily inserted.

According to the lock ring 34 of the first embodiment, the chamfered portion 43 is formed so that its diameter decreases from the outer edge of the annular portion 42 toward the outside. for that reason,
When the pipe 11 in which the core ring 30 is fitted is inserted into the pressing body 19 and the joint body 12, the flange 32 is formed by the chamfered portion 43 so that the second seal ring 27 and the third seal ring 2 are formed.
9 can be smoothly inserted without being caught.

(Second Embodiment) In the second embodiment, differences from the first embodiment will be mainly described. As shown in FIG. 7, in the lock ring 34 of the second embodiment,
The notch 39 is located at the center between all adjacent regulating pieces 36,
An arc-shaped notch is formed from the regulation piece 36 side to the base ring 35 side so as to correspond to the depth at which the regulation piece 36 bites into the pipe 11. The slit 40 has a predetermined depth from the center of the bottom of the notch 39 to the base ring 35, that is, a depth that allows the deformation of the restricting piece 36 when the pipe 11 is inserted into the lock ring 34.

Therefore, the lock ring 34 of the second embodiment is used.
According to this, the notch 39 is formed at the center between all the adjacent restriction pieces 36 such that the amount of biting of the restriction pieces 36 is a required amount that can prevent the pipe 11 from coming off. For this reason, it is possible to reliably limit the restriction piece 36 from biting into the pipe 11 by a required amount or more, and to reliably prevent the pipe 11 from being cut.

The slits 40 are formed between all adjacent restriction pieces 36. Therefore, when the end of the pipe 11 is inserted into the lock ring 34, all the restriction pieces 3
The pipe 11 can be easily inserted by allowing the outward spread of the pipe 6. In addition, the width of the base end of each restriction piece 36 can be ensured, and the strength can be more firmly maintained.

Further, the slit 40 is provided with the lock ring 34.
Are formed along a line extending radially from the center.
Therefore, when the pipe 11 is inserted into the lock ring 34, the restriction piece 36 is allowed to spread outward,
1 can be easily inserted.

It is to be noted that each of the above embodiments can be modified and embodied as follows. The base ends of the three or more restricting pieces 36 are connected to each other via the slits 40, and the notches 39 are formed between the adjacent restricting pieces 36, respectively.

With this configuration, the force of the restriction piece 36 biting into the pipe 11 can be strengthened, and when an external force acts in the direction in which the pipe 11 is pulled out, the restriction piece 36 Bending in the direction can be more firmly prevented.

A plurality of restricting pieces 36 are formed to protrude inward from the inner peripheral edge of the base ring 35 of the lock ring 34, and are not bent. In such a configuration, the pipe 1
When 1 is inserted into the lock ring 34, the restricting piece 36 bends in the axial direction, returns to its original state by elastic force, and its tip is cut into the outer periphery of the pipe 11, so that the pipe 11 can be stopped and restricted.

As shown in FIG. 8, a recess 38 is cut out from the outer peripheral edge of the base ring 35 to each regulating piece 36 so as to be located at the center of each regulating piece 36. In such a configuration, the pipe 11 is connected to the lock ring 34.
When inserted into the lock ring 34, the restriction piece 36 can easily spread in the axial direction, so that the pipe 11 can be easily inserted into the lock ring 34, and material can be saved.

The material of the lock ring 34 is changed to aluminum, iron or the like. Even with this configuration,
The function of the lock ring 34 can be reliably exhibited.

A slit 40 is formed in the center between the adjacent restriction pieces 36 so as to form a V-shaped notch from the restriction piece 36 side to the base ring 35 side so as to correspond to the depth at which the restriction piece 36 bites into the pipe 11. To do.

Also in this configuration, when the end of the pipe 11 is inserted into the lock ring 34, the restriction piece 36 can be spread outwardly, and the pipe 11 can be easily inserted. . In addition, the width of the base end of the regulating piece 36 can be ensured to maintain its strength.

As shown in FIG. 9, a reduced-diameter surface 44 is formed which gradually decreases in diameter from the base end side of the cylindrical portion 31 of the core ring 30 toward the inclined portion 33. With this configuration, it is possible to cope with variations in the inner diameter of the pipe 11, and the core ring 30 can be easily fitted inside the pipe 11.

Further, the technical idea grasped from the above embodiment will be described below .

[0052]

An annular receiving surface is provided in the cylindrical joint body, and a lock ring having a plurality of regulating pieces projecting inwardly and annular is engaged with the receiving surface, and the lock ring is positioned. The male screw part of the cylindrical pressing body to be fixed is screwed into the female screw part formed in the joint body, and the resin pipe is inserted through the pressing body until it comes into contact with the contact surface provided in the joint body. A joint in which the end of the pipe is engaged with the restriction piece of the lock ring to prevent the pipe from coming off, and the tip of each restriction piece of the lock ring is formed in an arc shape.

In this case, the end of the pipe is firmly connected to the joint by the restricting piece of the lock ring.
The pipe can surely be prevented from falling out of the joint, and the amount of bite can be restricted to prevent the pipe from being damaged.

[0055]

[0056]

The present invention is configured as described above, and has the following effects. According to the lock ring according to the first aspect of the present invention, it is possible to ensure that a required amount of the restricting piece is inserted into the resin pipe inserted into the joint, thereby preventing the pipe from falling out of the joint. In addition, the amount of bite can be regulated to prevent damage to the pipe.

Further , the restriction piece can be cut into the pipe by a required amount, and the pipe can be reliably prevented from coming off from the joint. In addition, lock the end of the pipe
When inserted into the ring,
With the aid of this, the pipe can be easily inserted. Ma
Also, maintain the strength by securing the width of the base end of the regulating piece
be able to.

According to the lock ring of the second aspect of the present invention, the tip of the regulating piece bites into the pipe and the regulating piece is
The balance of strength at the base end can be maintained,
Pipe can be reliably prevented from falling out of the
You.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a state where a pipe is inserted into a joint.

FIG. 2 is an exploded perspective view showing a joint.

FIG. 3 is a sectional view showing a coring of the embodiment.

4A is a plan view illustrating a lock ring, and FIG. 4B is a cross-sectional view illustrating the lock ring.

FIG. 5 is a side view showing a state where a coring is fitted into an end of the pipe.

FIG. 6 is an exploded side view showing a state in which a pipe is inserted into the joint body.

FIG. 7 is a plan view showing a lock ring according to a second embodiment.

FIG. 8 is a plan view showing another example of the lock ring.

FIG. 9 is an enlarged sectional view showing another example of the coring.

[Explanation of symbols]

11 pipe, 12 joint body, 15 first internal thread,
16 contact surface, 18 receiving surface, 19 pressing body, 22 second male screw portion, 34 lock ring, 35 base ring, 36 restricting piece, 37 joint, 39 notch, 40
…slit.

Claims (2)

(57) [Claims] 1. A structure in which a male screw portion of a cylindrical pressing body is screwed with a female screw portion formed in a joint body while being engaged with an annular receiving surface provided in the cylindrical joint body. When a resin pipe is inserted into the joint to be pressed until it comes into contact with the contact surface provided in the joint body via the press body, the end of the pipe comes off from the joint. In the lock ring for preventing, a base ring engaged with the receiving surface and a plurality of restricting pieces protruding inward from the base ring by substantially the same length are provided, and a tip portion of each restricting piece is formed in an arc shape. And furthermore,
The depth of the tip of the regulating piece into the pipe between the regulating pieces
A notch is formed correspondingly, and a base is formed from the notch.
When the pipe is inserted over the sling,
Lock ring with slits to allow deformation . 2. An inner bottom portion of a notch portion and a tip portion of the regulating piece.
2. The lock ring according to claim 1, wherein the shape of the lock ring is substantially the same .