JP4387993B2 - Piping joint - Google Patents

Description

  The present invention relates to a pipe joint.

Conventionally, a pipe joint in which an annular seal member having elasticity is held in an annular holding groove of a cylinder and a gap between the pipe inserted into the cylinder and the cylinder is sealed by the seal member is provided. Widely used.
FIG. 7 shows an example.
In the figure, reference numeral 200 denotes a pipe joint, and 202 denotes a cylinder provided in the pipe joint 200.
An annular holding groove 204 is provided on the outer peripheral surface of the cylindrical body 202, and an O-ring 206 serving as an annular sealing member having elasticity is held therein, and the cylindrical body 202 is fitted in the axial direction of the cylindrical body 202. The O-ring 206 seals between the inserted pipe 208 and the cylinder 202.

By the way, in this pipe joint 200, when the pipe 208 is inserted into the tubular body 202 so as to be connected to the pipe joint 200, the front end surface 208 </ b> A of the pipe 208 forms a surface perpendicular to the axis of the pipe 208. As shown in FIG. 7 (b), the front end surface 208A of the pipe 208 is simultaneously brought into contact with the entire circumference of the O-ring 206 to reduce its diameter, and a large resistance force is suddenly generated at that time. For this reason, the pipe 208 must be inserted into the cylindrical body 202 with a strong force overcoming a large resistance force, and there is a problem that the workability of connecting the pipe 208 to the pipe joint 200 is poor.
FIG. 7 shows an example in which the pipe is inserted into the cylindrical body in an externally fitted state, but the seal is inserted into the cylindrical body in the internally fitted state and held on the inner peripheral surface of the cylindrical body. A similar problem arises in a pipe joint in which the member seals between the cylinder and the pipe.

The present invention has been devised to solve such problems.
The following Patent Document 1 discloses an invention concerning a universal pipe joint, in which an O-ring is provided in a state of being inclined with respect to the pipe axis direction. The O-ring is not inclined with respect to the insertion direction, and is different from the present invention.

Japanese Patent Laid-Open No. 9-60776

  The present invention is based on the above circumstances, reducing the resistance caused by the O-ring when inserting the pipe into the cylinder of the joint body, allowing the pipe to be smoothly inserted into the cylinder, and improving the connection workability of the pipe. The object of the present invention is to provide a pipe joint that can be improved.

  Thus, according to the first aspect of the present invention, an annular sealing member having elasticity is held in the annular holding groove of the cylindrical body, and the gap between the pipe inserted into the cylindrical body and the cylindrical body is held by the sealing member. In the pipe joint adapted to be sealed, the shape of the holding groove is inclined at least with respect to a direction perpendicular to the insertion direction of the pipe when the pipe is inserted into at least the cylindrical body. It is characterized by having a shape.

  According to a second aspect of the present invention, in the first aspect, the entire holding groove including the groove rear surface and the front groove front surface in the holding groove in the insertion direction of the pipe in the holding groove with respect to the pipe insertion direction. The seal member is restrained and held in the tilted state when the seal member is mounted.

  According to a third aspect of the present invention, in the first aspect, the rear surface of the groove, which is the back surface of the holding groove in the insertion direction of the pipe, is the inclined surface, and the front surface of the front groove is the cylinder. It is a surface perpendicular to the axis of the body, and when the pipe is inserted, the seal member is pushed and inclined by the pipe.

  According to a fourth aspect of the present invention, in the third aspect, the groove rear surface is formed by fitting a ring having the inclined surface into the cylindrical body.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the pipe joint causes the pipe to be inserted into the cylindrical body in an externally fitted state, and the holding groove and the sealing member are the cylindrical body. Further, the cylindrical body is provided with an end face on the side facing the front end face of the pipe when the pipe is inserted, and is deformed following the shape of the front end face so as to extend over the entire circumference. An elastic body that is brought into contact with the front end surface and that compresses and deforms in the axial direction as the pipe is inserted while preventing the seal member from protruding in the radial direction is fitted on the outer peripheral side of the seal member. Features.

Effects and effects of the invention

As described above, in the present invention, the shape of the holding groove of the cylindrical body is such that the seal member is inclined with respect to a direction perpendicular to the insertion direction of the pipe at least when the pipe is inserted into the cylindrical body. Therefore, according to the present invention, when a pipe whose tip surface forms a surface perpendicular to the axis is inserted into the pipe joint cylinder, the tip surface of the pipe is simultaneously brought into contact with the seal member over the entire circumference. The seal member can be elastically fitted to the pipe while the seal member is gradually elastically deformed as the pipe is inserted.
Therefore, a large resistance force is not suddenly generated when the pipe is inserted, and the pipe can be smoothly inserted into the cylindrical body, so that the workability of connecting the pipe to the pipe joint can be improved.

In the present invention, the entire holding groove can be inclined according to claim 2 with respect to the direction perpendicular to the insertion direction of the pipe, and the sealing member can be restrained and held in the inclined shape of the holding groove.
In this case, the seal member is held in an inclined state when the seal member is mounted on the cylinder.

  On the other hand, according to claim 3, the rear surface of the groove, which is the back surface in the insertion direction of the pipe in the holding groove, is formed on the inclined surface, and the front surface of the front groove is formed on the surface perpendicular to the axis of the cylinder. The seal member can be pushed and inclined by the pipe when the pipe is inserted.

In this case, the groove rear surface can be formed by fitting the ring having the inclined surface to the cylindrical body (Claim 4). The holding groove can be easily provided in the cylindrical body.
By the way, when the sealing member is in the inclined state as described above, there is a concern that the sealing member may rise from the holding groove when the pipe is inserted when the inclination angle is a large steep angle of a certain value or more.

  In this case, in the pipe joint in which the pipe is inserted into the cylinder body, the end face on the side facing the front end face of the pipe is deformed following the shape of the front end face of the pipe when the pipe is inserted. An elastic body that is elastically deformed in the axial direction as the pipe is inserted while preventing the seal member held on the outer circumferential surface of the cylindrical body from projecting in the radial direction by contacting the tip surface over the entire circumference. The cylindrical member is inserted into the outer peripheral side of the seal member. According to the fifth aspect, even when the seal member is inclined, the rising of the seal member can be prevented satisfactorily.

  In the present invention, it is desirable that the inclined angle be set to 7 degrees or less in order to prevent the inclined seal member from being lifted by insertion of the pipe.

Next, embodiments of the present invention will be described in detail with reference to the drawings.
1 to 3, 10 is a metal pipe joint, 12 is a joint body, and has a flange-shaped large-diameter tool hooking portion 14 on the outer peripheral surface on the right side of the tool hooking portion 14 in the figure. A male screw 16 is provided.
Further, a cylindrical inner cylinder (tubular body) 18 is integrally provided on the left side in the drawing opposite to the male screw 16.
A resin pipe 20 is inserted into the inner cylinder 18 in the axial direction in an externally fitted state, and is connected to the inner cylinder 18.
Here, an annular holding groove 22 is formed on the outer peripheral surface of the inner cylinder 18, and an O-ring 24 as an annular seal member having elasticity is held therein.

Reference numeral 26 denotes an outer cylinder provided in the pipe joint 10, which includes an outer sleeve 28 and an inner sleeve 30, and an insertion space 32 for the pipe 20 is formed between the inner sleeve 30 and the inner cylinder 18.
The outer sleeve 28 has a female thread 34 at the right end in the figure, and the female thread 34 is screwed and fixed to a male thread 36 of the joint body 12.
The outer sleeve 28 is formed with a stepped first sandwiching portion 38, and the first sandwiching portion 38 is made of a metal together with a second sandwiching portion 39 constituted by the end of the inner sleeve 30. A ring base 42 (see FIG. 3) of the disc spring-shaped lock ring 40 is sandwiched and held in the axial direction.

  As shown in FIG. 3, the lock ring 40 has a flat ring base portion 42 that forms an annular shape that is continuous in the circumferential direction, and protrudes obliquely inward in the radial direction from the ring base portion 42 toward the insertion direction of the pipe 20. In the form, it has a plurality of claws 44 formed side by side along the ring base 42 in the circumferential direction, and the claws 44 are formed on the outer surface of the pipe 20 inserted into the insertion space 32 as shown in FIG. The pipe 20 is locked in the unplugged state.

In FIGS. 2 and 3, reference numeral 46 denotes a metal coil spring fitted to the inner cylinder 18 on the outer peripheral side of the O-ring 24.
As shown in FIG. 3, the coil spring 46 has a tightly wound portion 50 formed by tightly winding without causing a gap between adjacent coils 48 and 48, and a gap between the coils 48 and 48. And the sparsely wound portion 52 that is sparsely wound in a state of forming the sparsely wound portion 52. The densely wound portion 50 is disposed on the side of the distal end surface 20A (see FIG. 2) of the pipe 20 before insertion, and the sparsely wound portion 52 Is fitted on the outer peripheral side of the O-ring 24 in a state of being positioned on the opposite side.

The coil spring 46 is used to prevent the O-ring 24 from being lifted from the holding groove 22 when the pipe 20 is inserted into the insertion space 32 and the pipe 20 is fitted to the inner cylinder 18 in the axially fitted state. Is provided.
Specifically, the coil spring 46 has the end surface of the densely wound portion 50 brought into close contact with the distal end surface 20A of the pipe 20 over the entire circumference, and based on the large elastic deformation of the loosely wound portion 52 as the pipe 20 is inserted. The O-ring 24 is prevented from being lifted and protruding from the holding groove 22 in a state where the O-ring 24 is compressed and elastically deformed in the axial direction and the densely wound portion 50 covers the O-ring 24 from outside.

As shown in FIGS. 1 and 2, the outer cylinder 26 in the pipe joint 10, specifically, the inner peripheral surface of the inner sleeve 30, has a large-diameter portion 54 on the right inner side of the insertion space 32 in the drawing. Further, the insertion side on the left side in the drawing is a small diameter portion 56, and a stepped portion 58 is formed between them.
On the other hand, the coil spring 46 also has a large diameter portion 60 on the right side and a small diameter portion 62 on the left side as shown in FIG.
As a result of the configuration, the coil spring 46 is prevented from falling off from the pipe joint 10 when the large-diameter portion 60 hits the stepped portion 58 of the inner sleeve 30 while being fitted to the pipe joint 10. .

In FIG. 1 to FIG. 3, reference numeral 64 denotes an unlocking member that also serves as a backup ring for the lock ring 40, and has a cylindrical shape. Is provided.
The unlocking member 64 serves to release the claw 44 from the outer surface of the pipe 20 by expanding the claw 44 of the lock ring 40 by a forward movement in the axial direction, specifically, rightward in the drawing. That is, it functions to release the lock of the pipe 20 by the lock ring 40.
The lock release member 64 is prevented from coming off in the axial direction by a first engagement portion 66 formed in an annular shape on the inner peripheral surface of the outer sleeve 28.

On the left side of the lock release member 64 in the drawing, a cylindrical release operation member 68 is provided so as to be movable forward and backward by a predetermined stroke in the axial direction.
The release operation member 68 is provided with an engaged portion 72 projecting radially outward. The release operation member 68 is engaged with the second engagement of the outer sleeve 28 with respect to the engaged portion 72. The part 70 is prevented from coming off from the outer cylinder 26 in the axial direction by engaging in the axial direction.
The release operation member 68 having a cylindrical shape is provided with a flange portion 74 protruding radially outward at the shaft end portion thereof.

In this embodiment, as shown in FIGS. 2 and 4, the entire holding groove 22 is at an angle θ with respect to the direction perpendicular to the insertion direction of the pipe 20, which is the axial direction of the inner cylinder 32 (FIG. 4B). The O-ring 24 which is inclined and is held there is also held in a correspondingly inclined state.
Specifically, the groove holding surface 22 including the groove rear surface 22A and the front groove front surface 22B, which are the back side surfaces in the insertion direction of the pipe 20, and the groove rear surface 22A and the groove front face 22B, are arranged before the pipe 20 is inserted. In the state, it is inclined with respect to the direction perpendicular to the insertion direction of the pipe 20.

  Therefore, in the present embodiment, when the pipe 20 whose tip surface 20A forms a surface perpendicular to the axis is inserted in the axial direction in an externally fitted state with respect to the inner cylinder 18, the tip surface 20A is formed as shown in FIGS. At the same time, the O-ring 24 is not brought into contact with the entire circumference of the O-ring 24. First, a part (lower part in FIG. 5) of the O-ring 24 is partially brought into contact with the O-ring 24 and elastically deformed in the reduced diameter direction. It fits in the lower part (FIG. 5 (I)), and further, as the pipe 20 moves forward, the middle part of the O-ring 24 fits in the pipe 20 (FIG. 5 (II)), and finally the entire O-ring 24 is piped. 20 (FIG. 5 (III)), elastically contacts the inner peripheral surface of the pipe 20, and seals between the pipe 20 and the inner cylinder 18.

  Therefore, in this embodiment, when the pipe 20 is inserted, a large resistance force is not generated, and the pipe 20 can be smoothly inserted into the inner cylinder 18 with a small force. The connection workability of 20 can be improved.

FIG. 6 shows another embodiment of the present invention.
In this embodiment, a small-diameter portion 76 is partially formed in the inner cylinder 18, and an elastic ring 80 having an inclined surface and having a notch 78 at a predetermined circumferential direction is fitted therein to form the holding groove 22. In addition, an inclined groove rear surface 22A is formed on the inclined surface of the elastic ring 80, and an axially perpendicular groove front surface 22B is formed on the stepped surface on the front end of the small-diameter portion 76. This is an example in which 24 is mounted and held.

In this embodiment, when the O-ring 24 is set in the inner cylinder 18, that is, when mounted in the holding groove 76, the O-ring 24 stands in a direction perpendicular to the axis, but when the pipe 20 is inserted, as the pipe 20 is inserted. The O-ring 24 is inclined, and in the inclined state, the O-ring 24 is gradually elastically fitted to the inner surface of the pipe 20 from the lower part in the drawing.
Therefore, also in this embodiment, when the pipe 20 is inserted, there is no sudden large resistance based on the elastic deformation of the O-ring 24, and the resistance of the O-ring 24 is gradually generated as the pipe 20 is inserted. 20 can be smoothly inserted with a small force.

  In this embodiment, the elastic ring 80 is fitted to the small diameter portion 76 of the inner cylinder 18 to form the inclined groove rear surface 22A. In this case, the inner cylinder 18 can be easily provided with the holding groove 22. it can.

Although the embodiment of the present invention has been described in detail above, this is merely an example.
For example, in the present invention, a holding groove is formed on the inner peripheral surface of a cylinder and a seal member is held therein, and the pipe is inserted into the cylinder so as to be fitted into the cylinder and the seal member is provided between the pipe and the cylinder. The present invention can also be applied to pipe joints that are sealed with a pipe, and the present invention can also be applied when connecting pipes made of materials other than resin pipes. It can be configured in variously modified forms within a range that does not.

It is a figure which partially cuts and shows the piping joint of one Embodiment of this invention in a piping connection state. It is a figure which shows the piping joint of the embodiment in the state before piping connection. It is a perspective view which decomposes | disassembles and shows the piping joint in the same embodiment. It is operation | movement explanatory drawing of a coil spring at the time of inserting piping into the piping joint of the embodiment. It is action | operation explanatory drawing of the inclination O-ring at the time of inserting piping into the piping joint of the embodiment. It is a figure which shows other embodiment of this invention. It is a figure which shows the conventional piping joint.

Explanation of symbols

10 Piping joint 18 Inner cylinder (cylinder)
20 piping 22 holding groove 22A groove rear surface 22B groove front surface 24 O-ring 46 coil spring 80 elastic ring

Claims (5)

In a pipe joint in which an annular seal member having elasticity is held in an annular holding groove of a cylinder, and a seal between the pipe inserted into the cylinder and the cylinder is sealed with the seal member The shape of the holding groove is such that at least when the pipe is inserted into the cylindrical body, the seal member is inclined with respect to a direction perpendicular to the insertion direction of the pipe. Piping joint.   In claim 1, the entire holding groove including the groove rear surface and the front groove front surface in the holding groove in the insertion direction of the pipe is inclined with respect to the pipe insertion direction, A piping joint, wherein the seal member is restrained and held in the inclined state when the seal member is mounted.   The groove rear surface, which is the back surface in the insertion direction of the pipe in the holding groove, is the inclined surface in claim 1, and the front groove front surface is a surface perpendicular to the axis of the cylindrical body. A pipe joint, wherein the seal member is pushed by the pipe and tilted when the pipe is inserted.   4. The pipe joint according to claim 3, wherein the groove rear surface is formed by fitting a ring having the inclined surface to the cylindrical body.   The pipe joint according to any one of claims 1 to 4, wherein the pipe joint is inserted into the cylinder body in an externally fitted state, and the holding groove and the seal member are provided on an outer peripheral surface of the cylinder body. Further, the cylindrical body is brought into contact with the distal end surface over the entire circumference by deforming the end surface on the side facing the distal end surface of the pipe when the pipe is inserted, following the shape of the distal end surface, A pipe joint characterized in that an elastic body that compressively elastically deforms in the axial direction as the pipe is inserted is fitted on the outer peripheral side of the seal member while preventing the seal member from protruding in the radial direction.

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