JP2006009884A - Pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive pipe joint capable of shortening piping work time. <P>SOLUTION: The pipe joint 1 is provided with a joint main body 2 in which a connection pipe 6 is inserted into at least one end side, a seal member 3 fitted into inside of the joint main body 2, a retainer member 4 abutting on the seal member 3 and a plurality of bolts 5 pressing the retainer member 4 in the pipe axis direction. At least in its one end part, the joint main body 2 has a flange part 21 with inner diameter into which the connection pipe 6 can be inserted. A bolt 5 is screwed into the flange part 21. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pipe joint that connects a plurality of connecting pipes, and relates to a mechanical pipe joint that is used, for example, to connect a drain pipe in a building and has excellent workability and economy.

  Conventionally, cast iron pipes, steel pipes or vinyl chloride pipes have been used as pipes for draining miscellaneous wastewater and sewage drainage in buildings, etc., and among these pipe fittings that used to connect steel pipes were previously screwed. Many pipe fittings were used. However, when using a screw-type pipe joint, it is necessary to thread the pipe end of the connection pipe, especially when connecting a large-diameter connection pipe with a nominal diameter exceeding 4 inches. Since a large connecting tool is used in addition to pipe threading, there is a problem that the time required for pipe construction becomes long. In order to eliminate such problems, it is common to connect the drainage pipe with a mechanical pipe joint that does not require pipe end processing of the connection pipe.

  Various types of mechanical pipe joints (hereinafter simply referred to as pipe joints) for connecting steel pipes have been proposed. However, there are connection pipe receptacles on the back side and flanges on the outer periphery of the ends. In general, a pipe joint having a structure in which a seal member and a retaining member are accommodated inside a joint main body having a structure, and the seal member is pushed into a flange portion of the joint main body by a pressing portion connected by a bolt. According to this pipe joint, the construction time can be shortened significantly compared to screw-in type pipe joints, but when assembling the seal member and retaining member to the joint body at the construction site, the assembly order is incorrect and the parts are not inserted. Or, there may be a problem that parts are lost during transportation to the construction site. Therefore, the present applicant has proposed a pipe joint described in Patent Document 1. The main part of this pipe joint is shown in FIG. In the pipe joint shown in FIG. 7, the seal member 66 and the retaining member 67 are joined and integrated by the connecting pin 68, and the seal component is sandwiched between the joint body 62 and the seal member pressing portion 63. By tightening the main body 62 and the seal member pressing portion 63 with a bolt 64 and a nut 65, the outer peripheral portion of the connection pipe 6 is sealed. According to this pipe joint, since the seal member 66 and the retaining member 67 are integrally connected, the assembling work of the parts at the time of piping construction is simplified, so that the frequency of occurrence of poor assembly can be reduced. is there.

Japanese Patent Laying-Open No. 2002-005354 (second page, FIG. 1)

  In recent years, it has been desired to reduce the cost of piping members and to be able to quickly perform piping work regardless of skilled workers. However, when connecting a steel pipe using the above pipe joint, mounting of a sealing part integrated with the pressing portion 63 to the end of the connection pipe 6, assembling to these joint bodies, and the bolt 64 and nut 65 Since the tightening and three processes are required, the construction time cannot be reduced so much. Moreover, according to the pipe joint having the above-described structure, the number of parts increases and it is difficult to reduce the cost.

  Accordingly, an object of the present invention is to solve the above-described problems and provide a pipe joint that can reduce the construction time and cost.

  In order to achieve the above object, a pipe joint according to the present invention includes a joint main body into which a connecting pipe is inserted at least on one end side, a seal member mounted inside the joint main body, and a retainer member that contacts the seal member. And a plurality of bolts that press the retainer member in the tube axis direction, and the joint body has a flange portion having an inner diameter through which the connection tube can be inserted at least at one end thereof, The bolt is screwed together.

  In the present invention, the retainer member is a ring-shaped member comprising a retainer flange portion with which the end face of the bolt abuts and a retainer taper portion formed downwardly from the retainer flange portion toward the back side of the joint body. Is preferred.

  In the present invention, the retainer member preferably has an elastically deformable shape, and more preferably, the retainer flange portion has a portion formed in a shape complementary to the end face of the bolt. .

  According to the pipe joint of the present invention, after the connecting pipe is inserted from the opening formed at the end of the joint main body to the depth of the joint main body, the bolt is screwed into the flange formed at the end of the joint main body. Connection pipes and pipe joints can be connected by carrying out a simple operation of tightening.

  Moreover, since components such as a seal member can be incorporated in the joint main body in advance before construction, erroneous mounting and non-mounting of components can be eliminated, and the construction time can be shortened.

  In addition, it is not necessary to provide a pressing member for compressing the seal member outside the joint body, and the number of parts can be reduced and the cost can be reduced as compared with a conventional mechanical pipe joint.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 relates to an embodiment of a pipe joint of the present invention, and is a half-longitudinal sectional view showing a state before a connecting pipe is inserted into the pipe joint and tightened with a bolt, and FIG. 2 shows a main part of FIG. FIG. 3 is a cross-sectional view showing a main part of FIG. 1, showing a state where a pipe connection is completed by tightening a bolt, FIG. 4 is a cross-sectional view of a retainer member before being attached to a pipe joint, and FIG. FIG. 6 and FIG. 6 are plan views of the retainer member showing a state where it is attached to the pipe joint.

  The pipe joint 1 shown in FIG. 1 has a joint body in which a connection pipe 6 in which a fluid (for example, drainage) flows is inserted at both ends (only one is shown in FIG. 1) and a gap 20 is formed between the pipes 1. 2, a seal member 3 and a retainer member 4 that are mounted inside the joint body 2, and a plurality of screws that are screwed into the end of the joint body 2 and arranged along the circumferential direction (for example, symmetrically arranged). The bolt 5 is provided. Since this pipe joint 1 has a bilaterally symmetric structure around the center in the pipe axis direction, in the following description, only one part is described in detail, and the description of the other part is omitted.

  As shown in FIG. 2, the joint body 2 is formed in a substantially cylindrical shape as a whole, and has a flange portion 21 at its end, and a gap 20 is formed between the inner diameter of the flange portion 21 and the connection pipe 6. It is set to such a dimension. In the example of FIG. 2, the flange portion 21 is integrally formed by bending the end portion of the joint body 2 inward by press molding or the like, but a ring-shaped member is prepared and welded or bolted or the like. It can also be fixed to the joint body 2. In order to restrict the insertion length of the connecting pipe 6 at the end of the joint body 2, the wall part 25 against which the end face of the connecting pipe 6 abuts and the connecting pipe 6 are arranged along the pipe axis direction. A receiving port 26 including a first parallel portion 24 for guiding is formed. Further, the tapered surface 27 and the second parallel portion 28 are formed by forming a tapered surface 27 that is inclined upward from the receiving port 26 toward the flange portion 21 and a second parallel portion 28 that extends in the tube axis direction therefrom. And a seal member 3 in a region (hereinafter referred to as a seal member housing portion) 23 surrounded by the flange inner surface 29 and the outer peripheral surface of the connection pipe 6, and a retainer for uniformly compressing the seal member and preventing the connection pipe from coming out A member 4 is mounted. The retainer member 4 is assembled so as to abut on the end surface of the seal member 3 opposite to the side where the tapered surface 27 is formed. The joint body 2 can be formed of, for example, gray cast iron described in JIS G 5501, spheroidal graphite cast iron described in JIS G 5502, or carbon steel. Further, in order to impart corrosion resistance to the joint body 2, it is desirable to perform a surface treatment by galvanization or epoxy coating.

  The seal member 3 is an annular member made of an elastic body. When the seal member 3 is accommodated in the seal member accommodating portion 23 and compressed, the seal member 3 closely contacts the tapered surface 27 and the second parallel portion 28. The portion 32 has a formed shape. The inner peripheral portion of the seal member 3 has a shape parallel to the tube axis direction, and the inner diameter dimension when not compressed is set to be larger than the outer diameter of the connection pipe 6. Considering ease of insertion of the connecting pipe 6 and sealing performance, the inner diameter of the sealing member 3 is desirably about 1.01 to 1.05 times the outer diameter of the connecting pipe 6. The seal member 3 can be formed of, for example, water-resistant styrene butadiene rubber (SBR) or nitrile rubber (NBR) having excellent chemical resistance.

  As shown in FIG. 4, the retainer member 4 is a ring-shaped member formed of, for example, a metal thin plate and having a substantially U-shaped longitudinal section, and includes a retainer taper portion 44, a radius retainer outer peripheral portion 42, and a retainer flange portion 43. . As shown in FIG. 5, a plurality of cuts 47 are formed in the retainer taper portion 44 along the circumferential direction (for example, at equal intervals), and the notch portions 45 are formed in a part of the retainer member 4 in the circumferential direction. Is formed. On the end face of the retainer flange portion 43, a pin 41 is provided at a position symmetrical to the notch portion 45 and protrudes in the tube axis direction toward the opening side of the joint. It is desirable that the retainer 4 and the pin 41 are made of a metal material that is not easily corroded even when used for a long period of time and has a high mechanical strength, for example, a stainless steel plate.

  For example, four internal thread portions 22 are formed at equal intervals on the same circumference on the flange portion 21 formed at the end of the joint body 2, and the bolts 5 are screwed there. On the end face of the bolt 5, a recess 51 for receiving a pin 41 protruding from the end face of the retainer member 4 is formed. Accordingly, when the bolt 5 is screwed in, the pin 41 is supported by the bolt 51, so that the retainer member 4 is prevented from rotating in the circumferential direction, and the retainer member 4 can be fixed inside the joint body 2. Become. Here, if the end surface of the retainer flange portion 43 and the end surface of the bolt 5 can complement each other, the retainer member 4 can be positioned. Therefore, instead of providing the pin 41 on the retainer member 4, the retainer A concave portion or a through hole may be provided in the flange portion 43, while a convex portion may be provided on the end surface of the bolt 5. As the bolt 5, a commercially available steel bolt may be used as it is, or, for example, an anaerobic adhesive may be applied to the screw portion to prevent loosening.

  By using the pipe joint 1 described above, for example, the connection pipe can be connected by the following procedure. First, the seal member 3 and the retainer member 4 are mounted inside the joint body 2. The seal member 3 and the retainer member 4 can be attached to the joint main body 2 independently, but the pipe construction work can be efficiently performed by assembling and integrating both the members in advance. .

What is necessary is just to pressurize from the outer periphery toward an inner periphery, when attaching the retainer member 4 to the coupling main body 2. FIG. By doing so, since the notch 47 and the notch 45 are present, the whole is elastically deformed, and as shown in FIG. 6, one end overlaps the other end in the circumferential direction with the notch 45 interposed therebetween. Thus, an overlapping portion 46 is formed. The retainer member 4 thus reduced in diameter is mounted inside the joint body 2.
Further, in order to easily attach the retainer member 4 to the joint body 2, the retainer member 4 may be a two-part ring in which a predetermined number of notch portions 45 are formed on the inner peripheral side. Each of the two split rings is fixed with a pin 41 protruding in the tube axis direction, and is inserted into the joint body 2 so as to be fitted with the recess 51 on the end face of the bolt 5. By doing so, two overlapping portions 46 having high mechanical strength can be formed.

  Next, the connecting pipe 6 is inserted from the end of the joint body 2 until the pipe end abuts against the wall 25. At this time, since the pipe end of the connection pipe 6 is inserted along the first parallel portion 24, smooth insertion can be performed. After confirming that the connecting pipe 6 has been inserted into the joint body 2, the bolt 5 is tightened, whereby the seal member 3 is pressed via the retainer member 4. As a result, the seal member 3 is compressed, and the wedge-shaped end portion thereof bites between the taper surface 27 and the wall portion 25 and is tightly adhered to the outer peripheral surface of the second parallel portion 28 and the connecting pipe 6. Secure sealing is performed.

  Further, as the seal member 3 is compressed by tightening the bolt 5, the retainer taper portion 44 is deformed so as to fall toward the connection tube 6, so that the edge portion 48 at the inner peripheral edge of the retainer taper portion 44 is the outer peripheral surface of the connection tube 6. Bite into. Thereby, the connection pipe 6 is prevented from being pulled out, and the pipe joint 1 and the connection pipe 6 are firmly connected. The number of bolts 5 may be set as appropriate according to the tightening force or the like.

  According to said connection structure, the outer peripheral part of the connecting pipe 6 and the inner periphery of the sealing member accommodating part 23 are sealed with the sealing member 3, and a favorable watertight effect | action can be acquired. Further, the retainer member outer peripheral portion 42 is in contact with the inner periphery of the seal member accommodating portion 23, and the inner diameter of the retainer taper portion 44 is in contact with the outer periphery of the tube 6 in an oblique state so that the connecting tube 6 is not easily pulled out from the joint 1. Can be joined together. Therefore, according to the joint structure shown in FIG. 1, the connection pipe can be reliably joined by a simple operation such as inserting the connection pipe into the pipe joint in which the above-described components are incorporated and tightening the bolt 5. Construction time is greatly shortened and highly reliable piping can be realized.

  Needless to say, the present invention is not limited to the structure described above, and various changes can be made without changing the gist of the invention.

FIG. 5 is a half-longitudinal sectional view showing a state before inserting a connecting pipe of a pipe joint according to an embodiment of the present invention and before tightening a bolt. It is sectional drawing which shows the principal part of FIG. It is a fragmentary sectional view which shows the principal part of a bolt fastening completion state after inserting a connection pipe in the pipe joint of FIG. It is sectional drawing of a retainer member. It is a top view of a retainer member. It is a top view of a retainer member after being attached to a joint main part. It is a longitudinal cross-sectional view which shows the principal part of the conventional pipe joint.

Explanation of symbols

1: pipe joint, 2: joint body, 3: seal member, 4: retainer member, 5: bolt, 6: connecting pipe, 20: gap, 21: flange part, 22: female thread part, 23: seal member accommodating part, 24: 1st parallel part, 25: Wall part, 26: Receptor, 27: Tapered surface, 28: 2nd parallel part, 29: Flange inner surface, 31: Tapered part, 32: Parallel part, 41: Pin, 42 : Retainer outer peripheral part, 43: retainer flange part, 44: retainer taper part, 45: notch part, 46: overlap part, 47: notch, 48: edge part, 51: recessed part

Claims (4)

A joint main body into which a connecting pipe is inserted at least at one end side, a seal member mounted inside the joint main body, a retainer member that comes into contact with the seal member, and a plurality of bolts that press the retainer member in the pipe axis direction The joint main body has a flange portion having an inner diameter through which the connection pipe can be inserted at least at one end thereof, and the bolt is screwed into the flange portion. The retainer member is a ring-shaped member comprising a retainer flange portion with which an end face of the bolt abuts and a retainer taper portion formed downwardly from the retainer flange portion toward the back side of the joint body. Item 1. The pipe joint according to Item 1. The pipe joint according to claim 2, wherein the retainer member has an elastically deformable shape. 4. The pipe joint according to claim 3, wherein the retainer flange portion has a portion formed in a shape complementary to the end surface of the bolt.

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