JP2001056080A - Pipe fitting structure - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To suppress the deformation of the insertion tube which causes the detachment of the inlet tube and the insertion tube, and to cause the vibration during the assembly work and the flow velocity of the transport fluid, etc. In addition, even when the inner diameter of the synthetic resin insertion tube portion fluctuates within a large tolerance range, the fitting operation of the reinforcement cylinder to the insertion tube portion can be suppressed. Make sure you do it efficiently and with little effort. SOLUTION: A reinforcing cylinder 7 is provided in a region from a tip inside an insertion tube portion 2 to a portion corresponding to a biting action portion of a retaining member 4.
And the outer diameter of the reinforcing cylinder 7 is configured to be smaller than the inner diameter of the insertion pipe 2, and the reinforcing cylinder 7 is inserted into the insertion pipe 2.
A retaining portion 7B that protrudes radially outward from the inner peripheral surface of the inner peripheral surface and that elastically deforms inward in the radial direction as it is inserted into the insertion tube portion 2; The radially outward projection of 7B is different in the circumferential direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the present invention relates to a method for manufacturing a connector between an outer peripheral surface of an insertion tube made of synthetic resin and connected to an inner peripheral surface of the receiving tube, or the insertion tube. A retaining member that can bite into the outer peripheral surface of the insertion tube portion between the inner peripheral surface of the press ring and the outer peripheral surface of the insertion tube portion fixedly connected to the receiving tube portion from the tube axis direction in a state of being externally mounted. And cam means for displacing the retaining member to the smaller diameter side in accordance with the relative detachment movement between the receiving pipe portion and the insertion pipe portion, and at least the biting action portion of the retaining member from the tip inside the insertion pipe portion. The present invention relates to a pipe joint structure in which a reinforcing cylindrical body is internally fitted in a region corresponding to or near the region.

[0002]

2. Description of the Related Art In this type of pipe joint structure, an external force (tensile force in a pipe axis direction) acts on a receiving pipe section and an insertion pipe section in a detaching direction due to an earthquake, uneven settlement, or the like. However, since the retaining member is displaced to the reduced diameter side by the cam means with the relative detachment movement of the receiving tube portion and the insertion tube portion in the tube axis direction, the retaining member is moved by the outer peripheral surface of the insertion tube portion. As a result, the separation resistance between the receiving tube portion and the insertion tube portion increases. Moreover, since the insertion tube is made of a synthetic resin such as polyethylene, which excels in elongation and bending characteristics in the direction of the tube axis as compared with cast iron or the like, the direction of the tube axis caused by an earthquake, uneven settlement, etc. External force such as a tensile force and a bending moment of the insertion tube portion can be absorbed by utilizing the elongation characteristics and the bending characteristics of the insertion tube portion itself. Furthermore, even if the tightening force acting on the synthetic resin insertion tube increases as the retaining member is displaced to the reduced diameter side, the increased tightening force is applied to the reinforcing cylindrical body fitted inside the insertion tube. Therefore, deformation of the insertion tube portion inward in the radial direction due to the tightening force of the retaining member can be suppressed. Therefore, the function of preventing the insertion tube from detaching from the receiving tube can be enhanced by the synergistic effect of the increase in the separation resistance, the external force absorbing action of the insertion tube and the deformation suppressing action of the insertion tube in the radial direction. .

[0003] In the pipe joint structure having such advantages, conventionally, in order to suppress the displacement of the reinforcing cylindrical body due to vibration or impact during the assembling work or the flow velocity of the transport fluid, the insertion is conventionally performed. The outer diameter of the inner fitting tube portion of the reinforcing tube inserted into the tube portion is configured to be larger than the inner diameter of the insertion tube portion over the entire area in the axial direction of the tube, and the reinforcing tube is inserted into the insertion tube. It was press-fitted and fixed in the section (for example, see Japanese Utility Model Publication No. 5-9582).

[0004]

In the conventional pipe joint structure, the outer diameter of the reinforcing cylinder is larger than the inner diameter of the insertion pipe over the whole area in the axial direction of the pipe. At the time of press-fitting, when the frictional resistance between the inner peripheral surface of the insertion tube portion and the outer peripheral surface of the reinforcing cylinder becomes large, and when the reinforcing cylinder is press-fitted into the insertion tube portion by manual operation, the press-fitting is performed. Work requires a great deal of labor and time, and when the reinforcing cylinder is pressed into the insertion tube using mechanical force, there is a disadvantage that the press-fitting device tends to become large.

[0005] In particular, the longer the fitting length of the reinforcing cylinder press-fitted into the insertion pipe section in the tube axis direction is, the more likely the efficiency of press-fitting work is reduced. In the case of the pipe portion, the dimensional tolerance on the inner diameter side is larger than that of the insertion pipe portion made of cast iron, so that the dimensional tolerance of the outer diameter of the inner fitting tube portion of the reinforcing cylinder is on the larger diameter side, and When the dimensional tolerance of the inner diameter of the portion is shifted toward the smaller diameter side, the pressure input of the reinforcing cylinder to the insertion tube portion is remarkably increased, and the above-described disadvantage is more likely to be further promoted.

Therefore, the present inventor conducted various experiments, and found that even if the entire outer peripheral surface of the inner fitting tube portion of the reinforcing tubular body was not pressed against the inner peripheral surface of the insertion tube portion, that is, the insertion tube portion was not pressed. Even if there is a gap between the inner peripheral surface of the inner tube and the outer peripheral surface of the inner fitting cylindrical portion of the reinforcing tubular body fitted therein, due to the relative separation movement between the receiving tube portion and the insertion tube portion caused by the external force, When the retaining member is displaced to the reduced diameter side, or when the retaining member is displaced to the reduced diameter side by manual operation, the inner peripheral surface of the insertion tube portion is the outer periphery of the inner fitting cylindrical portion of the reinforcing cylindrical body. It has been found that an effect of suppressing the deformation in the radial direction by the reinforcing cylinder can be obtained by pressing against the surface.

A main object of the present invention is to suppress the deformation of the insertion tube portion, which causes the detachment between the receiving tube portion and the insertion tube portion, by rational remodeling of the reinforcing cylinder based on the above findings. However, it is possible to suppress the displacement of the reinforcing cylinder caused by vibrations during the assembly work and the flow velocity of the transport fluid, and the inside diameter of the synthetic resin insertion tube fluctuates within a large tolerance range. It is another object of the present invention to provide a pipe joint structure that can efficiently and reliably perform an internal fitting operation of a reinforcing tubular body to an insertion pipe section with a small amount of labor even under such conditions.

[0008]

According to a first aspect of the present invention, there is provided a fuel cell system comprising: an outer peripheral surface of a synthetic resin insertion tube inserted and connected to a receiving tube portion; and an inner peripheral surface of the receiving tube portion. During or
The outer peripheral surface of the insertion tube portion bites into the outer peripheral surface of the insertion tube portion between the inner peripheral surface of the pressing ring fixedly connected to the receiving tube portion from the tube axis direction in a state of being externally fitted to the insertion tube portion. A possible stopper member is provided, and cam means for displacing the stopper member to the diameter-reducing side with the relative detachment movement of the receiving tube portion and the insertion tube portion is provided, and at least the stopper member is moved from the distal end in the insertion tube portion. A pipe joint structure in which a reinforcing tubular body is internally fitted in a region corresponding to a biting action portion or a region up to the vicinity thereof, wherein the reinforcing tubular body is fitted in the insertion pipe portion. The diameter
The inner diameter of the insertion tube portion is smaller than the inner diameter of the insertion tube portion at or near the portion corresponding to the distal end portion of the insertion tube portion at the time of internal fitting. Forming a retaining portion that protrudes outward in the direction and elastically deforms radially inward with insertion into the insertion tube portion,
The point of the protrusion of the retaining portion outward in the radial direction is different in the circumferential direction.

According to the above-mentioned characteristic configuration, even if there is a gap between the inner peripheral surface of the insertion tube portion and the outer peripheral surface of the inner fitting tube portion of the reinforcing tubular body fitted therein, an earthquake or uneven settlement may occur. When the retaining member is displaced to the diameter-reduced side by the cam means due to the relative separation movement between the receiving tube portion and the insertion tube portion caused by an external force such as
Alternatively, when the retaining member is manually displaced to the reduced diameter side by the cam means when the inner peripheral surface of the insertion tube portion is pressed against the outer peripheral surface of the inner fitting tube portion of the reinforcing cylinder, the insertion tube portion may be displaced. It was found that deformation inward in the radial direction can be effectively suppressed, and within the range where the deformation suppressing effect is obtained, the outer diameter of the inner fitting tubular portion of the reinforcing tubular body is made larger than the inner diameter of the insertion pipe portion. By reducing the size, it is possible to reduce the insertion resistance during the work of fitting the reinforcing cylinder into the insertion tube.

However, in a state where the inner fitting tubular portion of the reinforcing tubular body is internally fitted at a predetermined position in the insertion pipe portion, the retaining portion formed on the reinforcing tubular body is in contact with the inner peripheral surface of the insertion tubular portion. Since the contact portion is elastically deformed inward in the radial direction by the contact, the retaining portion is pressed against the insertion tube portion by the elastic return force, and a frictional resistance is generated.
It is possible to suppress the displacement of the reinforcing cylindrical body due to vibration or impact during the assembling work or the flow velocity of the transport fluid.

In addition, since the protrusion of the retaining portion outwardly in the radial direction is made different in the circumferential direction, the portion where the radially outward protrusion is the largest is provided in the dimensional tolerance range of the insertion tube portion. It is possible to correspond to the minimum inner diameter within the dimensional tolerance range of the insertion tube portion, with the portion corresponding to the maximum inner diameter within, and having the minimum allowance for radially outward projection, for example,
It is possible to reduce the insertion resistance at the time of the inner fitting operation of the reinforcing tubular body, as compared with the case where the protrusion of the retaining portion in the radially outward direction is the same in the circumferential direction.

Therefore, while suppressing the deformation of the insertion tube portion which causes the detachment of the receiving tube portion and the insertion tube portion, the reinforcement caused by vibrations or impacts during the assembling work or the flow velocity of the transport fluid is suppressed. The displacement of the cylindrical body can be suppressed, and even under the condition that the inner diameter of the synthetic resin insertion tube portion fluctuates within a large tolerance range, the work of internally fitting the reinforcing cylinder to the insertion tube portion is less labor. Can be performed efficiently and reliably.

According to a second aspect of the present invention, the pipe joint structure is characterized in that the retaining portion is formed radially inward by bending a plurality of circumferential portions of the reinforcing cylinder radially outward. In addition to being constituted by elastically deformable retaining pieces, the retaining pieces are constituted by two or more types of protruding margins having different radially outwardly protruding margins.

[0014] According to the above-mentioned characteristic configuration, the plurality of retaining pieces constituting the retaining portion are formed by bending the reinforcing cylinder itself radially outward. Is composed of a retaining body made of an elastic material such as a spring material or a synthetic rubber, and is provided with the retaining portion as compared with a case where the retaining body is fixed to the outer peripheral surface of the reinforcing cylindrical body. Not only can the manufacturing cost of the reinforcing cylinder be reduced, but also the desired retaining function can be reliably exhibited over a long period of time.

According to a third aspect of the present invention, there is provided a pipe joint structure according to the third aspect of the present invention, in which, among the retaining pieces, the circumferential width of the retaining piece having a large radially protruding margin is radially outward. The protrusion margin is smaller than the circumferential width of the small retaining piece.

According to the above-mentioned characteristic configuration, of the plurality of retaining pieces constituting the retaining portion, the retaining piece having the largest radially outwardly protruding margin is provided within the dimensional tolerance range of the insertion tube portion. It is possible to correspond to the minimum inner diameter within the dimensional tolerance range of the insertion tube portion by using a retaining piece that can correspond to the maximum inner diameter of the insertion tube and minimize the radially outward protrusion. In addition, by making the circumferential width of the retaining piece having a large protrusion allowance small, even when the inner diameter of the insertion tube portion is the minimum within the dimensional tolerance range, the amount of elastic deformation inward in the radial direction is the largest. The operating force required for the elastic deformation of the retaining piece on the large protruding side becomes small.

Therefore, for example, a plurality of retaining pieces constituting the retaining portion have radially outwardly protruding allowances in the circumferential direction, and each retaining piece has the same circumferential width. Compared to the case where the inner diameter of the synthetic resin insertion tube part fluctuates within a large tolerance range, the fitting operation of the reinforcing cylinder to the insertion tube part can be performed with less labor compared to the case of Good and reliable.

A characteristic feature of the pipe joint structure according to claim 4 of the present invention is that both side edges in the circumferential direction of the retaining piece are bent and formed so that the edges project outward in the radial direction. . According to the above-mentioned characteristic configuration, as the inner fitting tube portion of the reinforcing tubular body is internally fitted at a predetermined position in the insertion tube portion, the retaining stopper portion formed to be bent at a plurality of positions in the circumferential direction of the reinforcing tubular body. The retaining pieces are pressed in contact with the inner peripheral surface of the insertion tube portion while being elastically deformed radially inward, and at this time, the edges formed on both circumferential edges of each retaining piece are inserted. Since it will bite into the inner peripheral surface of the pipe portion, it is possible to more effectively suppress the displacement of the reinforcing cylindrical body due to vibration or impact during the assembling work or the flow velocity of the transport fluid. Moreover,
Since the edge of the retaining piece is projected radially outward by bending the retaining piece, for example, the inner fitting cylindrical portion of the reinforcing tubular body is provided on the outer peripheral surface of the retaining piece with a predetermined shape in the insertion tube portion. As the fitting is inserted into the position, the manufacturing cost of the reinforcing cylindrical body having the biting portion is reduced as compared with the case where the biting portion biting into the inner peripheral surface of the insertion tube portion is formed to protrude. be able to.

According to a fifth aspect of the present invention, a characteristic feature of the pipe joint structure is that, among the retaining pieces, at least the edge of the retaining piece having a small radially outwardly protruding margin is inserted into the insertion pipe portion. The point is that an edge is formed which is pressed against the inner peripheral surface of the insertion tube by the elastic restoring force of the insertion.

According to the above-mentioned characteristic configuration, when the inner diameter of the insertion tube portion is biased toward the larger diameter side of the tolerance range, the retaining piece having a large radially outwardly protruding margin is mainly used for removal. The stopper function is exhibited, but even in this case, when the edge formed on the edge of the small stopper piece with a small protrusion margin is elastically pressed against the inner peripheral surface of the insertion tube portion, the insertion tube portion is The relative movement resistance with respect to the reinforcing cylinder is increased, and the displacement of the reinforcing cylinder due to vibration or impact during the assembling work or the flow velocity of the transport fluid can be more effectively suppressed.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIGS. 1 to 11
Is for inserting and connecting the insertion pipe 2 at one end side of a water pipe P made of polyethylene, which is an example of a fluid transport pipe made of synthetic resin, to the inlet pipe 1 of the joint body A made of cast iron in a sealed state. Fig. 2 shows a pipe joint structure of the present invention, and an inner peripheral surface 1a of the receiving pipe portion 1;
In addition, two annular grooves 1A having different groove widths in the tube axis X direction,
1B, of which a first annular groove 1A having a small groove width located on the receiving side seals between the inner peripheral surface 1a of the receiving tube portion 1 and the outer peripheral surface 2a of the insertion tube portion 2. The first elastic sealing material 3 to be attached is mounted, and the outer peripheral surface 2a of the insertion tube 2 inserted and connected to the receiving tube 1 is inserted into the second annular groove 1B having a large groove width located on the back side. An example of a retaining member that can be inserted therein is a retaining ring 4 made of a synthetic resin (for example, polyacetal or the like) or a metal (for example, stainless steel or the like) formed in a substantially C-shape that can be elastically reduced in diameter. And a second elastic sealing material 5 for sealing between the inner peripheral surface 1a of the receiving tube portion 1 and the outer peripheral surface 2a of the insertion tube portion 2 at a position on the back side of the retaining ring 4. is there.

As shown in FIG. 1, FIG. 7, and FIG. 11, the inner peripheral surface 1a of the receiving tube portion 1 has a peripheral surface located in the second annular groove 1B. The retaining ring 4 is displaced toward the diameter reducing side in accordance with the relative disengagement movement of the retaining ring 4 and the insertion pipe portion 2 in the tube axis X direction, that is, the retaining ring 4 is contracted against its elastic restoring force. A tapered cam surface 6 as a cam means for radially deforming is formed, and the insertion tube portion 2 is formed.
At least a portion corresponding to the biting action portion of the retaining ring 4 from the front end thereof or the vicinity thereof (the first region).
In the embodiment, in the insertion tube portion 2, a region slightly longer than a tube portion inserted into the receiving tube portion 1) is provided inside the insertion tube portion 2 in the radial direction due to the diameter reduction deformation of the retaining ring 4. A reinforcing cylinder 7 made of stainless steel (made of metal) for suppressing deformation toward the inside is fitted inside.

The outer diameter D1 of the inner fitting tube portion 7A of the reinforcing tubular member 7 which is fitted inside the insertion tube portion 2 is smaller than the inner diameter D2 of the insertion tube portion 2; It is configured to be slightly smaller than the minimum inner diameter D2 within the tolerance range of the pipe portion 2, and the distal end portion 7d of the reinforcing cylindrical body 7 is tapered so as to have a smaller diameter toward the distal end side. Further, of the reinforcing cylinder 7, a portion corresponding to the distal end of the insertion tube portion 2 at the time of internal fitting or near the portion (in this embodiment, the insertion tube portion 2
A base end portion 7e) corresponding to the distal end portion of the insertion tube portion 2 in a state of being internally fitted to a predetermined position in the inside thereof has an inner peripheral surface 2c of the insertion tube portion 2.
Retaining portion 7 projecting radially outwardly and elastically deforming radially inward with insertion into insertion tube portion 2.
B is formed, and the protrusion of the retaining portion 7B outward in the radial direction is made different in the circumferential direction.

That is, the retaining portion 7B is provided in each of FIGS.
As shown in the figure, a portion located at the base end portion 7e of the reinforcing cylindrical body 7 and between the adjacent V-shaped slits 7a formed at four places in the circumferential direction is bent radially outward. The retaining piece 7b is configured to be elastically deformable inward in the radial direction, and the retaining piece 7b is configured to have two types of protruding margins having different radially outward protruding margins.

Among the retaining pieces 7b, the circumferential width W1 of the retaining piece 7b, which has a large radial projection, is the circumferential width of the retaining piece 7b, which has a small radial projection. Each of the retaining pieces 7b having a smaller width than W2 and having a large radially outwardly protruding margin and a pair of retainingly retaining pieces 7b having a small radially outwardly protruding margin are respectively formed by a cylindrical shaft core (tube axis). Large and small protrusions are alternately arranged in the circumferential direction so as to face each other in the radial direction passing through the core X).

Of the retaining pieces 7b, the retaining piece 7b having the maximum radially outwardly protruding margin is provided by the insertion tube portion 2b.
With the retaining piece 7b corresponding to the maximum inner diameter within the dimensional tolerance range of and the protrusion margin to the radially outward direction is minimized,
The insertion tube 2 is configured to correspond to the minimum inner diameter within the dimensional tolerance range. That is, as shown in FIGS. 4 to 7, when the inner diameter D2 of the insertion tube portion 2 has the maximum diameter within the dimensional tolerance range, a pair of the protrusions to the radially outward direction are the largest. Only the retaining piece 7b is elastically deformed inward in the radial direction to retain and retain the reinforcing cylindrical body 7 fitted in a predetermined area in the insertion tube portion 2 as shown in FIGS. When the inner diameter D2 of the insertion tube portion 2 is the minimum diameter within the dimensional tolerance range, all the retaining pieces 7b are elastically deformed inward in the radial direction, but are mainly deformed outward in the radial direction. The pair of retaining pieces 7b having the minimum protrusion allow the reinforcing tubular body 7 fitted in a predetermined area in the insertion tube portion 2 to be retained and retained.

Further, of the retaining pieces 7b, the edge of the retaining piece 7b, which has a small radially protruding margin, is attached to the edge of the retaining piece 7b by its elastic restoring force as it is inserted into the insertion tube 2. Insertion tube part 2
An edge 7c to be pressed against the inner peripheral surface 2c is formed. When the inner diameter D2 of the insertion tube portion 2 is biased toward the larger diameter side of the tolerance range, the retaining piece 7b having a large radially outwardly protruding margin is mainly used to exhibit the retaining function. However, even in this case, a small retaining piece 7b with a protruding margin is used.
When the edge 7c formed at the end of the insertion tube 2 is elastically pressed against the inner peripheral surface 2c of the insertion tube 2, the relative movement of the insertion tube 2 and the reinforcing cylinder 7 in the tube axis X direction. The resistance is increased, and the displacement of the reinforcing cylinder 7 due to vibration or impact during the assembling work or the flow (flow velocity) of water (fluid) can be more effectively suppressed.

On the inner peripheral surface of the retaining ring 4, a large number of biting projections 4 that can bite into the outer peripheral surface 2a of the insertion tube portion 2 are provided.
a, and the outer peripheral surface 4b of the retaining ring 4 is formed as a tapered surface along the cam surface 6. Also, even when the tapered outer peripheral surface 4b of the retaining ring 4 is not in contact with the cam surface 6, the retaining projection 4a is formed by the elastic restoring force of the retaining ring 4 toward the reduced diameter side. The insertion ring 2 is configured to slightly bite into the outer peripheral surface 2a of the insertion tube 2, and the distal end portion of the insertion tube 2 is provided with a retaining ring 4 with an elastic restoring force as the insertion tube 2 is inserted. A tapered second cam surface 2b for expanding and deforming the diameter is formed.

At the other end of the receiving pipe portion 1 of the joint body A, a bolt 11 and a nut 12 are connected to a flange portion 10 provided on a pipe fitting such as another pipe or a gate valve. The flange portion 13 to be connected is integrally formed.

FIG. 6 shows a state in which the inner fitting tube portion 7A of the reinforcing tubular body 7 is fitted over a predetermined region in the insertion tube portion 2.
And the inner peripheral surface 2c of the insertion tube portion 2 as shown in FIG.
Even if there is a gap between the inner cylindrical portion 7A of the reinforcing cylindrical body 7 fitted therein and the outer peripheral surface, as shown in FIG. 7 and FIG. Reception pipe part 1
When the insertion tube 2 and the insertion tube 2 move relatively away from each other, the retaining ring 4 is reduced in diameter by the tapered surface 6 as a cam means, and the insertion tube 2 is radially inwardly deformed in accordance with the diameter of the stopper ring 4. Since the inner peripheral surface 2c of the tube portion 2 is pressed against the outer peripheral surface of the inner fitting tube portion 7A of the reinforcing cylinder 7, the insertion tube portion 2
Can be suppressed from deforming inward in the radial direction.

[Second Embodiment] FIGS. 12 and 13 show an insertion pipe of a water pipe P made of polyethylene which is an example of a fluid transport pipe made of synthetic resin, in an inlet pipe section 1 of a joint body A made of cast iron. Part 2
Another embodiment of a pipe joint structure for inserting and connecting a pipe in a sealed state is shown, and an inner peripheral surface 1a of a receiving pipe section 1 is provided on the insertion pipe section 2.
And an outer sealing surface 20 made of synthetic rubber (for example, styrene-butadiene rubber) capable of sealing between the outer tube 2 and the outer peripheral surface 2a of the insertion tube portion 2; Cast iron press ring 2 that can be compressed to a watertight state)
And a fastening means 22 for fastening and connecting the pressing wheel 21 and the receiving tube portion 1 from the tube axis X direction.

The inner peripheral surface 21a of the pressing wheel 21 and the insertion tube 2
Is an example of a retaining member that can bite into the outer peripheral surface 2a of the insertion tube portion 2 between the outer peripheral surface 2a and the outer peripheral surface 2a. A retaining ring 4 made of synthetic resin (for example, polyacetal or the like) or metal (for example, stainless steel or the like) is provided, and the inner peripheral surface 21a of the pressing wheel 21 is provided with the fastening means 2.
The retaining ring 4 is displaced toward the reduced diameter side in accordance with the relative approach movement between the pressing wheel 21 and the receiving tube portion 1 accompanying the tightening operation of 2, that is, the retaining ring 4 resists its elastic restoring force. This is an example of a cam means for reducing the diameter by forming a tapered cam surface 6 having a larger diameter toward the receiving tube portion 1 side.

In the first half of the tightening operation by the fastening means 22, only the elastic seal material 20 is provided between the elastic seal material 20 and the pressing ring 21 and the retaining ring 4 opposed to each other in the tube axis X direction. By pressing and compressing, the tightening operation after the elastic seal material 20 has reached the set compression state, the cam surface 6 causes the retaining ring 4 to bite until the bite-in state, against the elastic restoring force. An operating means 23 is provided.

Further, when the retaining ring 4 is slightly biting into the outer peripheral surface 2a of the insertion tube portion 2, an external force (in the detaching direction) is applied to the insertion tube portion 2 and the insertion tube portion 2 which are inserted and connected. When the receiving tube portion 1 and the insertion tube portion 2 move away from each other due to the action of the pulling force in the tube axis X direction, the tapered outer peripheral surface 4b of the retaining ring 4 moves along with the cam surface 6. The stopper ring 4 is deformed by being pressed, and the biting projection 4a of the retaining ring 4 is configured to further bite into the outer peripheral surface 2a of the insertion tube portion 2.

In the second embodiment, the region from the tip in the insertion tube portion 2 to at least a portion corresponding to the biting action portion of the retaining ring 4 (in the second embodiment, of the insertion tube portion 2, In a region slightly longer than the sum of the length of the tube portion inserted into the receiving tube portion 1 and the length of the pressing ring 21 in the tube axis direction), the diameter of the insertion tube portion 2 accompanying the diameter reduction deformation of the retaining ring 4. A reinforcing cylinder 7 made of stainless steel (made of metal) for suppressing deformation inward in the direction is internally fitted.

The outer diameter D1 of the inner fitting tube portion 7A of the reinforcing tube 7 which is fitted inside the insertion tube portion 2 is smaller than the inner diameter D2 of the insertion tube portion 2. It is configured to be slightly smaller than the minimum inner diameter D2 within the range of the dimensional tolerance of the tube portion 2, and the distal end portion 7d of the reinforcing cylindrical body 7 is tapered so as to have a smaller diameter toward the distal end side. Furthermore,
At or near the portion corresponding to the distal end of the insertion tube portion 2 at the time of internal fitting of the reinforcing tubular body 7 (in the embodiment, the insertion tube portion 2 is fitted at a predetermined position inside the insertion tube portion 2). The inner peripheral surface 2 of the insertion tube portion 2 is
c, and protrudes radially outward from the insertion tube 2
A retaining portion 7B which is elastically deformed inward in the radial direction as it is inserted into the inside is formed, and the amount of protrusion of the retaining portion 7B outward in the radial direction is made different in the circumferential direction. That is, the retaining portion 7B radially outwardly folds a portion located at the base end portion of the reinforcing cylindrical body 7 and between adjacent V-shaped slits 7a formed at four locations in the circumferential direction. The retaining piece 7b is formed by bending and formed elastically deformable inward in the radial direction, and the retaining piece 7b is configured to have two types of projection allowances having different radial allowances. ing.

Among the retaining pieces 7b, the circumferential width W1 of the retaining piece 7b having a large radially protruding margin is the circumferential width of the retaining piece 7b having a small radially protruding margin. W2 has a width smaller than that of the retaining piece 7b.
Among them, the edge of the retaining piece 7b, which has a small radially outward protruding margin, is attached to the inner peripheral surface 2c of the insertion tube portion 2 by its elastic restoring force as it is inserted into the insertion tube portion 2. Edge 7c to be pressed
Are formed.

The sequential actuating means 23 moves the elastic seal member 20 between the retaining ring 4 and the elastic seal member 20 in accordance with the relative approach movement between the pressing ring 21 and the receiving tube portion 1. A metal such as stainless steel having a first pressing surface 24a for pressing and compressing from the X direction and a second pressing surface 24b capable of pressing the retaining ring 4 on the cam surface 6 side of the pressing ring 21 from the tube axis X direction. Press body 24 made of plastic or synthetic resin
The pressing ring 2 extends over a region where the intermediate pressing body 24 and the inner peripheral surface of the pressing ring 21 radially oppose or substantially oppose each other.
Until the elastic sealing material 20 is brought into the set compression state along with the relative close movement between the elastic seal member 20 and the receiving pipe portion 1, the pipe between the cam surface 6 of the pressing wheel 21 and the second pressing surface 24b of the intermediate pressing body 24 is formed. The opposing interval in the direction of the axis X is regulated to an interval at which the retaining ring 4 in the non-biting state does not elastically deform to the reduced diameter side, and
When the elastic sealing material 20 is in the set compression state, the elastic member 20 is sheared between the outer peripheral surface of the intermediate pressing body 24 and the inner peripheral surface 21a of the pressing ring 21 to release the distance regulation, that is, the cam of the pressing ring 21 Surface 6 and second pressing surface 24b of intermediate pressing body 24
And a spacing control member (shear pin with a metal head such as a copper alloy or an aluminum alloy) 25 that allows relative approach movement in the X-axis of the tube axis.

The fastening means 22 includes two bolt insertion holes 27 of the connection flange portion 26 of the receiving tube portion 1 and a bolt insertion hole 29 of the connection projection 28 of the pressing ring 21 which are opposed to each other in the tube axis X direction. T inserted through the bolt insertion holes 27 and 29
It is composed of a V-shaped bolt 22A and a nut 22B.

Since the details of the reinforcing cylinder 7 and the retaining ring 4 are the same as those of the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

[Third Embodiment] In each of the above embodiments,
The retaining portion 7B is bent radially outward at a base end portion of the reinforcing cylindrical body 7 and a portion located between adjacent V-shaped slits 7a formed at four locations in the circumferential direction. Although it is constituted by the formed retaining piece 7b which can be elastically deformed inward in the radial direction, as shown in FIG. 14, the reinforcing cylinder 7 has a center in the direction of the cylinder axis (tube axis) from the base end thereof. A plurality of radially outwardly formed intermediate portions deviated to the side are punched out in the radial direction, and the punched-out retaining portions 7B are provided with the plural radially inwardly deformable retaining pieces 7b. May be configured.

[Fourth Embodiment] In each of the above embodiments,
The retaining portion 7B is composed of a retaining piece 7b which is formed by bending a plurality of locations in the circumferential direction of the reinforcing cylinder 7 radially outward and which can be elastically deformed inward in the radial direction. 7
Although the outer peripheral surface of b is formed in an arc shape, as shown in FIG. 15, the second edge 7f projects radially outward from both circumferential edges of the retaining piece 7b along the slit 7a. It may be carried out by bending and forming in a state. According to this embodiment, the inner fitting tube portion 7A of the reinforcing tubular member 7 is
As the inner tube is fitted at a predetermined position in the inside, the retaining piece 7b of the retaining portion 7B bent at a plurality of positions in the circumferential direction of the reinforcing cylindrical body 7 is brought into contact with the inner peripheral surface 2c of the insertion tube portion 2. It is pressed against while being elastically deformed inward in the radial direction by the contact, and at this time, the second edges 7f formed on the both circumferential edges of the retaining pieces 7b are engaged with the inner peripheral surface 2c of the insertion pipe portion 2. Therefore, it is possible to more effectively suppress the displacement of the reinforcing cylinder 7 due to vibration or impact during the assembling work or the flow (flow velocity) of the transport fluid. Moreover, since the second edge 7f of the retaining piece 7b projects radially outward by bending the retaining piece 7b, for example, the inside of the reinforcing cylinder 7 is formed on the outer peripheral surface of the retaining piece 7b. As the fitting tube portion 7A is internally fitted to a predetermined position in the insertion tube portion 2, the insertion tube portion 2
The manufacturing cost of the reinforcing cylindrical body 7 having the biting portion can be reduced as compared with the case where the biting portion biting into the inner peripheral surface 2c is formed protruding.

[Other Embodiments] (1) In each of the above-described embodiments, an example in which a coupling flange portion is integrally formed on the other end side of the receiving tube portion 1 in the tube axis direction as the joint body A is described. However, the present invention is not limited to this configuration. For example, the joint body A may include a pair of receiving pipe sections 1 to which the insertion pipe sections 2 are separately inserted and connected. Instead of such a joint body A,
It may be a receiving pipe portion formed on the connection port side of a pipe joint device such as a gate valve. (2) In each of the above embodiments, the retaining portion 7B is
A plurality of the circumferential portions of the reinforcing cylindrical body 7 are formed of the retaining pieces 7b which are bent outward in the radial direction.
May be constituted by a retaining body made of an elastic material such as a spring material or a synthetic rubber, and the retaining body is fixed to the outer peripheral surface of the reinforcing cylinder 7. (3) In each of the above-described embodiments, as the inner fitting tube portion 7A of the reinforcing tubular member 7 is fitted inside the insertion tube portion 2 at a predetermined position, the inner fitting surface 7c of the insertion tube portion 2 bites. The biting portion is formed by radially outwardly protruding edges 7f formed on both circumferential edges of the projecting retaining piece 7b.
The retaining piece 7b may be constituted by a projection formed on the outer peripheral surface thereof. (4) In each of the above-described embodiments, the reinforcing tubular body 7 that suppresses the radially inward deformation of the insertion tube portion 2 due to the diameter reduction deformation of the retaining ring 4 is provided from the tip inside the insertion tube portion 2. Although the reinforcement cylinder 7 is fitted over a wide area beyond the biting action portion of the retaining ring 4, at least the biting action portion of the retaining ring 4 is inserted from or near the tip in the insertion tube portion 2. What is necessary is just to be internally fitted over the area | region to the corresponding part or its vicinity. (5) In each of the above embodiments, the retaining piece 7b
Are configured as two types of protrusions with different radially outward protrusions, but may be configured with three or more types of protrusions with different radially outward protrusions. Further, two or more types of retaining pieces 7b having different radially outwardly protruding margins may be formed in such a manner that they are misaligned in the tube axis X direction in a state where the small protruding margins are located on the tip side. Good. (6) In each of the above embodiments, the reinforcing cylinder 6 is made of stainless steel, which is an example of metal, but may be made of synthetic resin.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a pipe joint structure of the present invention.

FIG. 2 is a perspective view of a reinforcing cylinder.

FIG. 3 is a front view of a reinforcing cylinder.

FIG. 4 is a longitudinal sectional view showing an elastically deformed state of the insertion tube portion having the maximum inner diameter and the reinforcing cylinder in the course of the inner fitting.

FIG. 5 is a longitudinal sectional view showing an elastically deformed state when the insertion of the insertion tube portion having the maximum inner diameter and the reinforcing cylinder is completed.

FIG. 6 is an enlarged longitudinal sectional view of a main part of the pipe joint when the insertion pipe part is at the maximum inner diameter.

FIG. 7 is an enlarged longitudinal sectional view of a main part when the receiving tube part and the insertion tube part are relatively moved apart from the state of FIG. 6;

FIG. 8 is a longitudinal sectional view showing an elastically deformed state of the insertion tube portion having the minimum inner diameter and the reinforcing tubular body during the fitting process.

FIG. 9 is a longitudinal sectional view showing an elastically deformed state when the insertion of the insertion tube portion having the minimum inner diameter and the reinforcing cylinder is completed.

FIG. 10 is an enlarged longitudinal sectional view of a main part of the pipe joint when the insertion pipe has a minimum inner diameter.

FIG. 11 is an enlarged longitudinal sectional view of a main part when the receiving tube portion and the insertion tube portion have relatively moved from the state of FIG. 10;

FIG. 12 is a longitudinal sectional view showing a second embodiment of the pipe joint structure of the present invention.

FIG. 13 is an enlarged cross-sectional view of a main part during assembly.

FIG. 14 is a longitudinal sectional view of a reinforcing tubular body showing a third embodiment of the pipe joint structure of the present invention.

FIG. 15 is a partially cutaway front view of a reinforcing cylinder showing a fourth embodiment of the pipe joint structure of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receiving pipe part 1a Inner peripheral surface 2 Insertion pipe part 2a Outer peripheral surface 2c Inner peripheral surface 4 Prevention member (prevention ring) 6 Cam means (taper surface) 7 Reinforcement cylinder 7A Internal fitting cylinder part 7B Prevention part 7a Slit 7b Retaining piece 7c Edge 21 Pressing wheel 21a Inner peripheral surface X Tube axis

Claims (5)

[Claims] 1. A receiving member which is inserted between an outer peripheral surface of a synthetic resin insertion tube inserted into and connected to a receiving tube portion and an inner peripheral surface of the receiving tube portion, or externally attached to the insertion tube portion. A retaining member provided between the inner peripheral surface of the press ring fixedly connected to the mouth tube portion from the pipe axis direction and the outer peripheral surface of the insertion tube portion, the stopper member being capable of biting into the outer peripheral surface of the insertion tube portion; Along with providing cam means for displacing the retaining member to the reduced diameter side with the relative disengagement movement between the pipe portion and the insertion tube portion, a portion corresponding to at least a biting action portion of the retaining member from the tip in the insertion tube portion or the like. In a pipe joint structure in which a reinforcing cylinder is internally fitted to a region up to near, the outer diameter of the inner fitting cylinder of the reinforcing cylinder that is internally fitted to the insertion pipe is larger than the inner diameter of the insertion pipe. And a portion corresponding to the distal end portion of the insertion tube portion at the time of internal fitting, or near the portion. Has a retaining portion that protrudes radially outward from the inner peripheral surface of the insertion tube portion, and that elastically deforms radially inward with insertion into the insertion tube portion. A pipe joint structure in which protrusions of the retaining portion radially outwardly differ in a circumferential direction. 2. The retaining portion is formed of a retaining piece that is elastically deformable inward in the radial direction and is formed by bending a plurality of locations in the circumferential direction of the reinforcing tubular member outward in the radial direction. 2. The pipe joint structure according to claim 1, wherein the retaining pieces are formed in two or more types of protrusions having different radial protrusions. 3. The circumferential width of the retaining piece having a large radially outwardly protruding margin is smaller than the circumferential width of the retaining piece having a small radially outwardly protruding margin. The pipe joint structure according to claim 2, wherein the pipe joint structure has a small width. 4. The pipe joint structure according to claim 2, wherein both side edges in the circumferential direction of the retaining piece are bent so as to protrude radially outward. 5. An insertion pipe portion having an elastic restoring force as the insertion piece is inserted into the insertion pipe portion, at least at an edge of the retention piece having a small radially protruding margin. The pipe joint structure according to any one of claims 2 to 4, wherein an edge pressed against an inner peripheral surface of the pipe joint is formed.