JP2001027375A - Joint for resin pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make connection work easily and quickly performable even in a narrow job site, obtain a firm coming-off lock of a resin pipe, so that a stable connection condition with no chatter can be held. SOLUTION: This joint comprises a joint main unit 2 having an insertion inner cylinder part 5 inserted into a resin pipe 1 and an outer cylinder unit 3 halving a spiral groove 6 in an internal peripheral surface also externally fitted to the joint main unit 2 so as to envelop the insertion inner cylinder part 5. In addition, a coil spring 4, mounting an inner end part 4a locked to an inner end side of the outer cylinder unit 3 further with an intermediate location screwed to the spiral groove 6 and removably locking an outer end part 4b to an outer end side of the outer cylinder unit 3 to diametrically spread an internal diameter against elastic force so as to be formed larger than an external diameter of the pipe 1 to have the internal diameter smaller than the external diameter of the pipe 1 in a free condition, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a joint for a resin pipe.

[0002]

2. Description of the Related Art Heretofore, there has been widely used a method in which a tapered male screw portion is cut at the end of a resin pipe to be connected, and a female screw portion of a joint is screwed to this.

[0003]

However, in this joint, if the work site is small and the joint main body is large or L-shaped, the joint main body is rotated and screwed into the resin pipe. May not be able to be performed, causing a problem. Further, when the thickness of the resin pipe is small, it is difficult or impossible to machine the external thread. Further, when screwing and connecting, the resin pipe may be subjected to a force and may be deformed or damaged.

Accordingly, the present invention provides a resin pipe joint that can easily and quickly perform a connection operation even in a small site, can firmly prevent the resin pipe from coming off, and can maintain a stable connection state without rattling. The purpose is to provide.

[0005]

In order to achieve the above object, a joint for a resin pipe according to the present invention comprises: a joint main body having an insertion inner cylindrical portion inserted into the resin pipe; An outer cylinder body having a spiral groove and externally fitted to the joint body so as to surround the insertion inner cylinder part; an inner end part fixed to the inner end side of the outer cylinder body, and an intermediate part Is screwed into the spiral groove, and furthermore, the outer end is releasably locked to the outer end side of the outer cylinder so as to resist the elastic force so that the inner diameter is larger than the outer diameter of the pipe. And a coil spring having an inner diameter smaller than the outer diameter of the pipe in a free state.

A joint body having an insertion inner cylinder portion inserted into the resin pipe; having a spiral groove on an inner peripheral surface and being fitted around the joint body so as to surround the insertion inner cylinder portion; An outer cylinder body; a small cylinder body rotatably connected to an outer end side of the outer cylinder body so as to be rotatable around an axis; an inner end portion fixed to the inner end side of the outer cylinder body; The intermediate portion is screwed into the spiral groove, and the outer end is fixed to the outer end of the small cylinder,
The small cylinder is locked to the outer cylinder so as to be rotatable and switchable, and is expanded against an elastic force so that the inner diameter is larger than the outer diameter of the pipe. A coil spring having an inner diameter smaller than the outer diameter of said pipe;
It is composed of

A joint body having an insertion inner cylinder portion inserted into the resin pipe; a helical groove formed on the inner peripheral surface, and the joint body having a spiral groove surrounding the insertion inner cylinder portion; An outer cylinder rotatably fitted on the outer cylinder; an inner end fixed to the joint main body, and an intermediate portion screwed into the spiral groove; The outer cylindrical body is fixed to the end side and is locked to the joint body so as to be rotatable and switchable, and resists the elastic force so that the inner diameter is larger than the outer diameter of the pipe. A coil spring having an inner diameter smaller than the outer diameter of the pipe in a free state.

Further, the spiral groove on the inner peripheral surface of the outer cylinder has a shape having a tapered surface portion whose diameter is reduced outward.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing embodiments.

FIGS. 1 and 2 show an embodiment of a joint for a resin pipe according to the present invention. This joint comprises a resin pipe 1 made of cross-linked polyethylene, polyethylene or other resin.
And includes a joint body 2, an outer cylindrical body 3, and a coil spring 4. The opening side where the pipe 1 is inserted is defined as the outer end side.

The joint body 2 has, on one side, a plug-in inner cylinder part 5 inserted into the resin pipe 1, the other has a socket type having a male screw, and the other has the same structure. It may be a straight type or an elbow type having a structure, or a T-type as a whole, each of which is a cheese type having the same structure as described later, and is generally made of metal. More specifically, the insertion inner cylindrical portion 5 has a plurality of circumferentially extending annular ridges 8 on its outer peripheral surface 7 in the axial direction, and further has a circumferentially concave groove 9 on its outer peripheral surface 7. In the axial direction. An annular packing body 10 is inserted into the concave circumferential groove 9. The packing body 10 and the annular ridges 8 prevent the pipe 1 from being inserted into the insertion inner tube part 5 and prevent fluid from flowing. Leakage to the outside is prevented.

The outer cylindrical body 3 has a spiral groove 6 on the inner peripheral surface thereof.
Is fitted outside. More specifically, a mounting groove 11 is provided on an outer peripheral surface of an intermediate portion of the joint main body 2, and a protrusion 12 formed on the inner end side of the outer cylindrical body 3 by a plastic deformation such as a punch from the outside. The outer cylindrical body 3 is fitted into the mounting groove portion 11 so that the outer cylindrical body 3 does not come out of the joint body 2. Note that the outer cylinder 3 may be attached to the joint body 2 so as not to rotate, with the attachment groove 11 serving as a small recess.

The coil spring 4 has an inner end 4
a is fixed to the inner end side of the outer cylinder 3, and the intermediate portion is screwed into the spiral groove 6, and the outer end 4 b is detachably locked to the outer end of the outer cylinder 3. Thus, the pipe is in a pipe connection standby state in which the inner diameter Ds is expanded against the elastic force so that the inner diameter Ds becomes larger than the outer diameter Dp of the pipe 1.

More specifically, a through hole 13 is provided on the inner end side of the outer cylindrical body 3 and the inner end 4a of the coil spring 4 is provided.
Are inserted into the through-hole 13 in an inserted manner. A locking projection 14 is provided on the outer edge of the outer cylinder 3 so as to protrude outward in the axial direction, so that the outer end 4b of the coil spring 4 can be detached from the locking projection 14. It is locked. Further, an intermediate portion between the inner end 4a and the outer end 4b is loosely screwed into the spiral groove 6 of the outer cylindrical body 3. In addition, it is also preferable to provide a through hole on the outer end side of the outer cylinder body 3 and lock the outer end portion 4b in the through hole so that the outer end portion 4b can be detached.

[0015] The coil spring 4 is shown in FIG.
As shown in (a), in the free state, the outer diameter D of the pipe 1
It has an inner diameter Ds smaller than p, and as shown in FIG. 3B, the inner diameter Ds is expanded against the elastic force so as to be larger than the outer diameter Dp of the pipe 1. It is attached to the outer cylinder 3 as described above. Also, the height H from the inner end 4a to the outer end 4b of the coil spring 4 whose diameter is expanded as shown in FIG. 3B is larger than the height H in the free state shown in FIG. It is getting bigger.

As described above, the coil spring 4 in the standby state for connection of the pipe 1 to the main joint is resiliently urged, and as shown in FIGS. 1 and 2, the outer end 4b of the coil spring 4 Has a height Hx which is about to decrease.
The outer end 4b is locked to the locking projection 14 while the inner diameter Ds and the tensile force Fy for reducing the inner diameter Ds are applied.

After that, the pipe 1 is inserted into the main joint to connect the pipe 1. That is, as shown in FIGS. 2 and 4, in the vicinity of the outer end 4 b and the locking projection 14 of the outer cylinder 3.
A concave portion 15 is formed at an outer edge near the root of the groove. Then, as shown in FIG. 4A, a jig 16 (such as a pin or a screwdriver) is inserted into the recessed portion 15 and the outer end 4b is set to a height H.
The jig 16 applies a force to the outer end portion 4b against the tensile force Fx, and the outer end portion 4b engages the locking projection 14 as shown in FIG. When a force is applied so as to exceed the locking projection 14, the outer end 4b exceeds the locking projection 14 due to the tensile force Fy (the inner diameter Ds is about to be reduced).
As shown in FIG. 7, the outer end 4b is in a state of being separated from the locking projection 14.

Then, as shown in FIG. 5, the pipe 1 is connected to the main joint. Specifically, FIG.
When the outer end 4b is detached in the pipe connection standby state shown in (b) as described above, the coil spring 4 tightens the pipe 1 as shown in FIG. The inner diameter Ds of the coil spring 4 in the pipe tightened state is larger than the inner diameter Ds in the free state (FIG. 3A), and the height H of the coil spring 4 in the pipe tightened state is the free state. Since the coil spring 4 is larger than the height H shown in FIG. 3A, the coil spring 4 is tightening the pipe 1 in a state of being elastically urged. In addition, the coil spring 4
However, the inner diameter Ds of the coil spring 4 in the tightened state may be smaller than the outer diameter Dp of the pipe 1. Therefore, the retaining of the pipe 1 is further strengthened.

Thus, the pipe 1 in the connected state is
As shown in FIG. 5, the fastening force of the coil spring 4, the packing body 10, and the annular ridge 8 are firmly attached to the joint, and the pipe 1 is firmly prevented from coming off. Moreover, leakage of the fluid to the outside is prevented.

The spiral groove 6 on the inner peripheral surface of the outer cylinder 3
Is a shape having a tapered surface portion 17 that contracts outward,
As shown in FIG. 6 (a), when a pulling force is applied to the pipe 1, the coil spring 4 tightening the pipe 1
Moves along with the pipe 1 in the drawing direction (axial direction),
As shown in FIG. 6B, the coil spring 4 is pressed against the tapered surface portion 17 of the spiral groove 6. Then, as shown in FIG. 5, since the outer cylindrical body 3 is attached to the joint body 2 so as not to move in the axial direction, the tapered surface portion 17 presses the coil spring 4 and the coil spring 4 To the pipe 1 is increased. Therefore, when the pulling force of the pipe 1 increases due to such a wedge state, the tightening force further increases.

FIG. 7 shows another embodiment of the present joint. This joint includes a joint main body 2, an outer cylinder 3, a coil spring 4, and a small cylinder 18. A plurality of mounting grooves 19 are provided on the outer peripheral surface of the intermediate portion of the joint body 2,
A through insertion hole 20 is provided on the inner end side of the outer cylindrical body 3, and the locking tool 21 (such as a screw or a pin) is pressed (screwed or press-fitted) from the outside to form the through insertion hole 20 and the mounting groove. 19, the outer cylinder 3 is fixedly attached to the joint body 2.
The mounting groove 19 is used as a circumferential groove, and the outer cylinder 3 is connected to the joint body 2.
May be mounted so as to rotate relative to each other.

The coil spring 4 has an inner end 4
a is fixed to the inner end side of the outer cylindrical body 3, the intermediate portion is screwed into the spiral groove 6, and the outer end 4 b is fixed to the outer end side of the small cylindrical body 18. And the small cylinder 18 is the outer cylinder 3
The small cylindrical body 18 is rotatably connected to the outer end of the outer cylindrical body 3 so as to be detachable in the rotational direction (rotation locking switching is possible), and 3 (b))
A pipe connection standby state, in which the inner diameter Ds of the coil spring 4 is expanded to resist the elastic force so that the inner diameter Ds of the coil 1 becomes larger than the outer diameter Dp of the pipe 1, is established.

More specifically, the small cylinder 18 is rotatably mounted around the axis so as to surround the outer end of the outer cylinder 3. The inner end 4a of the coil spring 4 is fixed to the outer cylinder 3, the outer end 4b is fixed to the small cylinder 18, and the coil spring 4 expands in diameter against the elastic force. Therefore, the small cylindrical body 18 is moved by the tensile force Fy (the inner diameter Ds is about to be reduced) of the outer end 4b.
To rotate around the axis. However, a plurality of engaging protrusions 22 provided on the inner end edge of the small cylindrical body 18 are provided on the outer peripheral surface of the outer cylindrical body 3 (to face the engaging protrusions 22 ...). (Or engaging recesses), the small cylindrical body 18 maintains the state where the rotational force about the axis is urged, and FIG.
A pipe connection standby state is established (as shown in (b)).

Thereafter, the pipe 1 is inserted into the main joint to connect the pipe 1. That is, the engagement protrusion 22 of the small cylinder 18
Are disengaged from the engaging projections 23 of the outer cylinder 3 against the tensile force Fx of the outer end 4b (the height H is about to decrease), the small cylinder 18 The coil spring 4 is rotated around the axis (with the end 4b), and the coil spring 4 is brought into a pipe-tightened (connected) state (as shown in FIG. 3C). The small cylinder 18
Due to the pulling force Fx of the outer end portion 4b, the rod does not fall out of the outer cylinder body 3 in the axial center direction, but becomes firm.

When the connected pipe 1 is pulled out from the joint, the small cylinder 18 is rotated around the axis (relative to the outer cylinder 3) against the elastic force of the coil spring 4. Then, the engagement protrusions 22 of the small cylindrical body 18 are locked to the engagement protrusions 23 of the outer cylindrical body 3 so that the coil spring 4 is in a pipe connection standby state, and the pipe 1 can be pulled out. . Therefore, pipe 1
Replacement, re-work, etc., are facilitated.

FIG. 8 shows another embodiment of the present joint. This joint includes a joint main body 2, an outer cylindrical body 3, and a coil spring 4. The outer tubular body 3 is fitted around the joint body 2 so as to be rotatable around the axis so as to surround the insertion inner tubular portion 5. Further, the coil spring 4 has an inner end 4 a fixed to the joint body 2, an intermediate portion screwed into the spiral groove 6, and an outer end 4 b fixed to the outer end of the outer cylinder 3. Is being worn. Then, the outer cylinder 3 is locked to the joint main body 2 so as to be detachable in the rotation direction (rotation locking switching is possible), and the inner diameter Ds of the coil spring 4 is set to the pipe diameter (as shown in FIG. 3B). The pipe connection standby state is expanded to be larger than the outer diameter Dp of 1 and against the elastic force.

More specifically, the outer cylindrical body 3 is rotatably fitted to an intermediate portion of the joint main body 2 so as to surround the insertion inner cylindrical portion 5. The inner end 4a of the coil spring 4 is fixed to the joint body 2, the outer end 4b is fixed to the outer cylinder 3, and the coil spring 4
Is expanded against the elastic force, the outer cylindrical body 3 is axially moved relative to the joint body 2 by the tensile force Fy (the inner diameter Ds is about to be reduced) of the outer end 4b. Try to rotate around. However, a plurality of engaging protrusions 24 provided on the inner end edge of the outer cylindrical body 3 are provided on the outer peripheral surface of the intermediate portion of the joint body 2 (to face the engaging protrusions 24). (Or engagement recesses), so that
The outer cylindrical body 3 maintains the state where the rotational force about the axis is urged, and the coil spring 4 (as shown in FIG.
It is in the pipe connection waiting state.

Thereafter, the pipe 1 is inserted into the main joint to connect the pipe 1. That is, the engagement protrusion 24 of the outer cylinder 3
Are disengaged from the engagement projections 25 of the joint body 2 against the tensile force Fx (the height H is about to decrease) of the outer end 4b, the outer cylinder 3 The coil spring 4 rotates (as shown in FIG. 3C) around the axis (with the portion 4b), and the pipe is tightened (connected). The outer cylinder 3
From the joint body 2 by the tensile force Fx of the outer end 4b.
It does not fall outside in the axial direction, and it is solid.

When pulling out the connected pipe 1 from the joint, the outer cylinder 3 is rotated around the axis (relative to the joint body 2) against the resilience of the coil spring 4. By engaging the engaging projections 24 of the outer cylinder 3 with the engaging projections 25 of the joint body 2, the coil spring 4 can be brought into a pipe connection standby state, and the pipe 1 can be pulled out. Therefore, replacement of the pipe 1, reworking, and the like become easy, and
The number of parts is reduced.

The cross-sectional shape of the coil spring 4 is not limited to a circle but may be an ellipse or a polygon such as a triangle or a quadrangle. Further, as shown in FIG. 9 (a), a plurality of ridges 26 are provided on the outer peripheral surface of the coil spring 4, or as shown in FIG. By providing the ridges 26 or the like, the projections 26 may bite into the pipe 1 so that the pipe 1 is prevented from coming off firmly. Note that the ridge portion 26 may be in a fragmentary shape or a continuous shape.

The present invention is not limited to the above embodiment. For example, the coil spring 4 may be wound right or left, and the inner end 4a of the coil spring 4 can be detached. The design may be changed without departing from the spirit of the present invention.

[0032]

The present invention has remarkable effects as described below.

According to the first aspect, the pipe 1 can be easily inserted, and furthermore, the pipe 1 can be easily connected only by detaching the outer end 4b of the coil spring 4 from the outer cylinder 3, so that a small site can be installed. However, connection work can be performed easily and quickly. Further, since the connection is made by the resilient force of the coil spring 4 screwed into the spiral groove 6, the pipe 1 is firmly prevented from coming off, and the uniform force is applied to the entire circumference of the pipe 1. It can maintain a stable connection state.

According to the second aspect, the pipe 1 can be easily inserted, and furthermore, the pipe 1 can be easily connected only by detaching the small cylindrical body 18 from the outer cylindrical body 3, so that it can be easily and quickly performed even in a small site. Can be connected. Further, since the connection is made by the resilient force of the coil spring 4 screwed into the spiral groove 6, the pipe 1 is firmly prevented from coming off and the pipe 1
A uniform force is applied to the entire circumference of the device, and a stable connection state without rattling can be maintained. When the connected pipe 1 is pulled out from the joint, the pipe 1 can be pulled out by rotating the small cylinder 18 around the axis (relative to the outer cylinder 3). Replacement, reworking, and the like are facilitated.

According to the third aspect, the pipe 1 can be easily inserted, and furthermore, the pipe 1 can be easily connected only by detaching the outer cylinder 3 from the joint main body 2, and easily and quickly even in a small site. Connection work can be performed. Further, since the connection is made by the resilient force of the coil spring 4 screwed into the spiral groove 6, the pipe 1 is firmly prevented from coming off, and the uniform force is applied to the entire circumference of the pipe 1. It can maintain a stable connection state. When the connected pipe 1 is pulled out from the present joint, the outer cylinder 3 is rotated around the axis (relative to the joint main body 2), and the pipe 1 can be pulled out. And the work can be redone easily. In addition, the number of parts is reduced, the assembly is easy, the number of failures is small, and the cost is low.

When the pipe 1 is pulled out (according to claim 4), the coil spring 4 further tightens the pipe 1 so that the connected pipe 1 is more securely prevented from being pulled out.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing one embodiment of a resin pipe joint according to the present invention.

FIG. 2 is a side view showing a state where a pipe is not inserted.

FIG. 3 is an explanatory diagram of an operation of a coil spring.

FIG. 4 is an explanatory diagram of an operation of a main part.

FIG. 5 is a side sectional view showing a pipe connection state.

FIG. 6 is an explanatory diagram of an operation of a main part.

FIG. 7 is a side sectional view showing another embodiment of the joint for a resin pipe.

FIG. 8 is a side sectional view showing another embodiment of the joint for a resin pipe.

FIG. 9 is a sectional view showing another embodiment of the coil spring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe 2 Joint main body 3 Outer cylinder 4 Coil spring 4a Inner end 4b Outer end 5 Insert inner cylinder 6 Spiral groove 17 Tapered surface 18 Small cylinder Ds Inner diameter Dp Outer diameter

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Keiji Matsumoto 8-22 Kikusuicho, Kawachi Nagano City F-term in Higashio Mec Co., Ltd. (Reference) 3H015 HA01 3H019 JA01

Claims (4)

[Claims] 1. A joint body 2 having an insertion inner cylindrical portion 5 inserted into a resin pipe 1; and a joint having a spiral groove 6 on an inner peripheral surface and surrounding the insertion inner cylindrical portion 5. An outer cylinder 3 fitted externally to the main body 2; an inner end 4a is fixed to the inner end of the outer cylinder 3, and an intermediate portion is screwed into the spiral groove 6; The portion 4b is releasably locked to the outer end of the outer cylindrical body 3, and has a free diameter expanded against the elastic force so that the inner diameter Ds is larger than the outer diameter Dp of the pipe 1. And a coil spring 4 having an inner diameter Ds smaller than the outer diameter Dp of the pipe 1 in a state. 2. A joint body 2 having an insertion inner cylinder portion 5 inserted into the resin pipe 1; and a joint having a spiral groove 6 on an inner peripheral surface and surrounding the insertion inner cylinder portion 5. An outer cylinder 3 fitted externally to the main body 2; a small cylinder 18 rotatably connected to the outer end side of the outer cylinder 3 so as to be rotatable around an axis; And an intermediate portion is screwed into the spiral groove 6, and the outer end 4 b is connected to the small cylindrical body 18.
And the small cylindrical body 18 is locked to the outer cylindrical body 3 so as to be rotatable and switchable, so that the inner diameter Ds becomes larger than the outer diameter Dp of the pipe 1. In the free state, the coil spring 4 having an inner diameter Ds smaller than the outer diameter Dp of the pipe 1 is expanded against the elastic force.
And a coupling for a resin pipe. 3. A joint body 2 having a plug-in inner cylinder portion 5 inserted into the resin pipe 1; and a joint groove having a spiral groove 6 on an inner peripheral surface and surrounding the plug-in inner cylinder portion 5. An outer cylinder body 3 rotatably fitted around the main body 2 about an axis;
a is fastened to the joint main body 2, the intermediate portion is screwed into the spiral groove 6, and the outer end 4 b is fastened to the outer end of the outer cylinder 3. The cylindrical body 3 is locked to the joint body 2 so that the rotation can be switched.
a coil spring 4 having an inner diameter Ds smaller than the outer diameter Dp of the pipe 1 in a free state, which is expanded against the resilience so that s is larger than the outer diameter Dp of the pipe 1; A joint for a resin pipe, comprising: 4. The helical groove 6 on the inner peripheral surface of the outer cylindrical body 3 has a shape having a tapered surface portion 17 whose diameter is reduced outward.
4. The joint for a resin pipe according to 2 or 3.