JP2009257450A - Joint structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide joint structure not requiring advance machining with respect to a pipe, and minimizing calking work. <P>SOLUTION: A diameter small part 10d with an inner diameter the same as pipes 12a, 12b is formed in an inner circumference center part of a joint body 10 with an outer diameter D0, and a diameter large part 10f of a length L2 is formed continuous with vertical walls 10e of its both right and left sides. Stepped parts are formed by the diameter small part, the vertical walls, and the diameter large part, the pipes are respectively inserted into the stepped parts, and their end faces are abutted on each vertical wall. An adhesive premixed with particulate cast iron is interposed in thin annular areas (thick solid line parts) between an inner circumference face of the diameter large part and an outer circumference face of each pipe. Before the adhesive hardens, the diameter large part is pressed toward an axis from its outer side and caulked. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a structure of a pipe joint provided for a relatively low pressure fluid pipe, typically a tap water pipe.

  As a method of joining pipe materials such as metal pipes and pipe joints, a male thread is cut at the end of one pipe to be joined, and this is screwed into the end of the opposite pipe with the female thread cut. Although the method is normal, a sufficient thickness is required to perform threading, which increases the weight and the relative rotation between both pipes, which complicates the joining operation. was there. Furthermore, the pipe connected by such a conventional joining method is half the strength of the connection part compared to other parts, and is not satisfactory in terms of pressure resistance, air tightness, earthquake resistance, etc. due to insufficient screwing. There is.

By solving such problems, it is possible to make two pipes to be firmly joined without giving relative rotation to both pipes, and the cost required for joining is low and not a skilled worker. For the purpose of joining pipe materials that can be easily and reliably piped,
“The end of one of the tubes to be joined is processed with a diameter-expanding jig, and the receiving portion extends over a predetermined length, the tapered receiving portion gradually expands toward the tube end, and the cylindrical portion. And an inwardly bent end part in which the pipe end is bent inward by 90 ° or more, and the end part of the opposite pipe member is inserted into the inside with an elastic gasket ring interposed therebetween. A split tool having an inner surface with a taper forming portion that is substantially perpendicular to the section is disposed opposite to the outer peripheral surface of both pipes, and these split tools are brought close to each other along the pipe axis. The elastic gasket ring is compressed and adhered to the surface, and the inwardly bent end is bent inwardly by 90 ° or more, and is kept in the pipe material while keeping the gentle concave part toward the inside. "Technology has been developed. (Patent Document 1)

Furthermore, there is proposed a pipe material joining method having the same configuration as that of Patent Document 1 in which two C-shaped rings are combined in addition to a gasket ring. That is,
“An end portion of a pipe member to be joined is formed with a tapered portion that gradually increases in diameter toward the end of the tube and a large-diameter portion that remains the largest diameter, and the tapered portion is formed in the receiving portion. Insert the other tube material with a wedge-shaped annular gasket that is in close contact with the inner peripheral surface and a C-shaped ring that is in close contact with the inner surface of the large-diameter portion. A method has been proposed in which a clamping jaw having a tapered inner peripheral surface is pressed in the radial direction to plastically deform the large diameter portion into a tapered shape, and at the same time, the C-shaped ring is bitten into the other pipe. (Patent Document 2)

JP 6-41011 JP-A 63-290631

  However, in any of Patent Documents 1 and 2, as shown in FIGS. 1, 2, and 3, one pipe material end must be expanded in advance in a tapered shape, and a gasket, Two C-shaped rings must be prepared. In addition, a caulking tool must be prepared at the time of actual pipe connection work, which is troublesome because the caulking work is performed separately. Special attention should be paid to the order and orientation of the parts.

  The inventor of the present application has conducted intensive research, examination, and trial manufacture in order to solve the above-described problems. As a result, in the joining methods 1 and 2 of the patent document, the two pipe material end portions to be joined are basically exceeded. It was noted that the configuration based on the premise of lapping complicates the caulking work described above.

  Therefore, the object of the present invention is to make the two pipe material end portions not overlap, and almost no prior processing is required for the pipe for piping, and the caulking work can be performed as little and simple as possible. An object of the present invention is to provide a joint structure.

To achieve the above object, the joint structure according to the present invention comprises:
It consists of a pipe for piping and a joint body having a receiving part for receiving and fixing one end side including the end face of the pipe,
The receiving portion is
A first inner peripheral surface and a second inner peripheral surface having the same small diameter and large diameter as the inner diameter and outer diameter of the pipe, and a stepped portion made of a vertical wall formed therebetween,
The pipe end surface is in contact with the vertical wall, and the second inner peripheral surface of the stepped portion and the pipe outer peripheral surface facing the second inner peripheral surface are provided with an adhesive interposed therebetween. A retaining portion having a sealing function formed by caulking the inner peripheral surface from the outer side toward the outer peripheral surface of the pipe,
It is characterized by the following.

In that case, it is preferable to mix the granular material having a predetermined hardness with the adhesive.
In that case, the second inner peripheral surface of the joint body is previously formed with a groove for storing a capsule or bag body in which the adhesive or an adhesive mixed with the granular material is enclosed, As the pipe end face is inserted into the receiving portion, the capsule or bag body can be opened by the edge of the pipe outer peripheral face.
Furthermore, in that case, the material of the granular material can be a metal, ceramics, glass beads, sand, rocks, or a composition in which two or more of these are mixed.
In that case, the adhesive is preferably configured to retain predetermined elasticity in a state after curing.

The joint structure of the present invention described in claim 1 is:
A pipe body and a joint main body having a receiving portion for receiving and fixing one end side including the end face of the pipe, the receiving portion having a first diameter that is substantially the same as the inner diameter and the outer diameter of the pipe. A step portion comprising a first inner peripheral surface and a second inner peripheral surface, and a vertical wall formed therebetween;
The pipe end surface is in contact with the vertical wall, and the second inner peripheral surface of the stepped portion and the pipe outer peripheral surface facing the second inner peripheral surface are in a state where an adhesive is interposed, 2 Since it consists of a retaining portion with a sealing function formed by caulking the inner peripheral surface from the outer side toward the pipe outer peripheral surface,
The structure is very simple, and it is possible to simultaneously achieve a sealing function by caulking and an adhesive and a function of preventing the pipe from coming off and rotating.

According to the joint structure of the present invention described in claim 2, since the granular material having a predetermined hardness is mixed in the adhesive, the granular material is directly applied to the outer peripheral surface of the pipe and the second inner peripheral surface of the joint body. Further contact with each other and a part of the contact surface indent or bite in, so that a further retaining function and anti-rotation function can be obtained.
According to the joint structure of the present invention described in claim 3, a capsule or bag in which the second inner peripheral surface of the joint body encapsulates the adhesive or an adhesive mixed with the granular material in advance. A groove for accommodating a body is formed, and the capsule or bag body is opened by the edge of the outer peripheral end surface of the pipe as the pipe end surface is inserted into the receiving portion. In parallel, it is possible to accomplish work on the piping site more efficiently.

According to the joint structure of the present invention described in claim 4, since the material of the granular material is a metal, ceramics, glass beads, sand, rocks, or a composition obtained by mixing two or more of these, It is relatively inexpensive, and it is also possible to select a material having an appropriate hardness and particle size according to the material of the pipe and the joint body.
According to the joint structure of the present invention described in claim 5, since the adhesive retains a predetermined elasticity in the state after curing, even when an unexpected external force acts near the joint body. It is possible to respond flexibly without cracks or breakage at the joint between the pipe and the joint body.

FIG. 1 is an axial sectional view of an embodiment of a joint structure according to the present invention, in which (a) shows a state where pipes are coupled to both sides of the joint body, and (b) shows a Z portion of (a). FIG.
In FIG. 1 (a), reference numeral 10 denotes a joint body having an outer diameter D0, and an inner diameter of the joint body is the same as that of the pipes 12a and 12b, and a small diameter portion 10d having a length L1 is formed. A large-diameter portion 10f (see FIG. 2 (a)) having a length L2 is formed following the vertical walls 10e (see FIG. 2 (a)) on the left and right sides of the small-diameter portion 10d. Step portions are formed by the small-diameter portion 10d, the vertical wall 10e, and the large-diameter portion 10f, and pipes 12a and 12b having outer diameters d for piping are respectively inserted into the step portions, and the vertical walls 10e The end faces are in contact.
In the thin annular region between the inner peripheral surface of the large diameter portion 10f of the joint body 10 and the outer peripheral surfaces of the pipes 12a and 12b (thick solid line portions), an adhesive mixed with granular cast iron is interposed in advance. . And before the adhesive hardens | cures, as the arrow F shows, the large diameter part 10f is crushed toward the axial center from the outer side, and it is crimped.

  FIG. 1B is an enlarged detailed view of a Z portion surrounded by a chain line in FIG. 1A and schematically shows a cross section thereof. In FIG. 5B, reference numeral S denotes the annular region, and black granular particles are dispersed in the adhesive, and a part of the granular material is squeezed into the large diameter portion 10f of the joint body 10 by caulking. It shows a state in which the inner peripheral surface of the pipe 12a and the outer peripheral surface of the pipe 12a are indented, and the surfaces are partially indented, and are simply in contact with those surfaces without being bitten or indented. In this contact state, the effect of retaining and turning the pipes is slightly inferior compared to biting and dents, but since the granular material is in direct contact with those surfaces, it is more than the case of only the adhesive. It has a large resistance (with respect to the relative displacement between the pipe and the joint body). The inner diameter D1 of the large diameter portion 10f is smaller than that before caulking.

  The size of the granule may be larger than that shown in the figure, and the hardness of the granule is preferably equal to or greater than that of the joint body 10 and the pipe 12a, and the shape of the granule is not limited to a spherical shape. In addition to the above-described granular cast iron, the granular material may be a variety of metal oxides, compounds, ceramics, hard glass beads, or crushed rocks that are granulated, either alone or 2 It is also possible to use a mixture of more than one species. Reference numeral 14a is a ring arranged on the outer periphery of the pipe, which prevents the adhesive and / or the granular material from flowing out of the annular region during caulking. Therefore, it can be omitted from the viewpoint of simplifying the work.

As the adhesive, 1377P for fitting, manufactured by Three Bond Co., Ltd., can be used. This adhesive is flexible, and the curing speed is about 1 hour to practical strength and about 12 hours to final strength. The fitting strength is 23 MPa, the viscosity is 1900 cP, and the usable temperature is −40 to 120 ° C. This adhesive is recommended for fixing pipes. Of course, the adhesive is not limited to this, and may be a two-component adhesive such as an epoxy resin.
In the above-described example, the granular material is mixed in the adhesive, but the granular material is not mixed, and even when the caulking and the bonding agent are used alone, the length L2 in FIG. It is possible to obtain the effect.

FIG. 2 shows a mode in which a capsule or bag body in which an adhesive or an adhesive mixed with a granular material is enclosed is stored on the inner peripheral surface of the joint body, and (a) shows the axial direction of the joint body. (B) is a groove provided in an annular shape on the inner periphery of the joint body, and (c) is provided in a spiral shape on the inner periphery of the joint body. It indicates a groove.
In FIG. 2A, reference numeral 16 denotes a capsule or bag body in which an adhesive or an adhesive mixed with a granular material is enclosed, and an axial groove formed in the large diameter portion 10f of the joint body 10 The lower end portion of the capsule or bag body 16 projects inward from the inner peripheral surface of the large diameter portion 10f. Therefore, when the pipe 12a is inserted from the right, the capsule or bag 16 is broken by the edge of the outer periphery of the pipe end face, and the sealed adhesive and granular material flow out. A plurality of the grooves 10a are preferably provided on the inner peripheral surface of the large-diameter portion 10f.

In FIG. 2 (b), an annular groove 10b is provided at a position close to the opening end of the large diameter portion 10f, and a capsule or bag body 18 is disposed therein. Is opened by the edge portion by the insertion of the adhesive, and the encapsulated adhesive and granular material flow out.
FIG. 2C shows a state in which the capsule or bag body 20 is disposed in the spiral groove 10c.
The capsules or bag bodies 16, 18, and 20 may be a single one, but a plurality of capsules or bag bodies may be appropriately distributed in the grooves 10 a, 10 b, and 10 c.

  In the implementation test, pressure resistance after curing was performed using the above-mentioned adhesive mixed with several types of pipe outer diameters of 20 to 80 mm and granular cast iron. As a result, it was confirmed that the water pressure of about 1 MPa was sufficiently adaptable. From this result, it was found that even when impact pressure such as water hammer occurs during use, the joint structure of tap water piping is sufficiently practical.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these exemplified contents, and those skilled in the art can implement various modifications based on them. is there. For example, in the above description, the pipe is inserted and fixed from both sides of the joint body, but the pipe is inserted and coupled only from one side of the joint body, and a screw is provided on the inner or outer circumference of the other side. In short, it is sufficient that the receiving portion is configured on at least one side of the joint body.

It is sectional drawing of the axial direction of one Example of the coupling structure by this invention, Comprising: (a) shows the state which connected the pipe to the both sides of the coupling main body, (b) is an enlarged detail of the Z section of (a). FIG. The mode which stores the capsule or bag which enclosed the adhesive agent or the adhesive agent which mixed the granular material in the inner peripheral surface of a joint main body is shown, (a) is the storage part provided in the axial direction of the joint main body. (B) is a groove in which the storage portion is provided annularly on the inner periphery of the joint body, and (c) is a groove in which the storage portion is provided spirally on the inner periphery of the joint body. It shows that.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Joint main body 10a, 10b, 10c Groove 10d Small diameter part 10e Vertical wall 10f Large diameter part 12a, 12b Pipe 14a Ring 16, 18, 20 Capsule or bag body F Caulking force

Claims (5)

It consists of a pipe for piping and a joint body having a receiving part for receiving and fixing one end side including the end face of the pipe,
The receiving portion is
A first inner peripheral surface and a second inner peripheral surface having the same small diameter and large diameter as the inner diameter and outer diameter of the pipe, and a stepped portion made of a vertical wall formed therebetween,
The pipe end surface is in contact with the vertical wall, and the second inner peripheral surface of the stepped portion and the pipe outer peripheral surface facing the second inner peripheral surface are provided with an adhesive interposed therebetween. A retaining portion having a sealing function formed by caulking the inner peripheral surface from the outer side toward the outer peripheral surface of the pipe,
A joint structure characterized by comprising:   The joint structure according to claim 1, wherein a granular material having a predetermined hardness is mixed in the adhesive.   On the second inner peripheral surface of the joint main body, a groove for accommodating a capsule or a bag body in which the adhesive or an adhesive mixed with the granular material is enclosed is formed in advance, and the pipe end surface is 2. The joint structure according to claim 1, wherein the capsule or the bag is opened by an edge of the outer peripheral end surface of the pipe as it is inserted into the receiving portion.   4. The joint according to claim 1, wherein the granular material is metal, ceramics, glass beads, sand, rock, or a composition obtained by mixing two or more of these. 5. Construction.   The joint structure according to any one of claims 1 to 4, wherein the adhesive retains a predetermined elasticity in a state after being cured.

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