JP6093193B2 - Pipe joint structure - Google Patents

Description

  The present invention relates to a pipe joint structure, and more particularly to a pipe joint structure including a cap member and a connection joint member connected to a pipe end.

  As a conventional joint structure for connecting a polyethylene pipe and a cast iron pipe, a mechanical joint structure as shown in FIG. 6 is known.

  In this joint structure, a joint member or cast iron pipe 22 connected to an end of a polyethylene pipe 21 includes a mechanical joint part 24 having a flange 23. A reinforcing member 25 is driven into the end portion of the polyethylene tube 21 to increase the rigidity of the end portion of the polyethylene tube 21, and a stopper that includes a lock ring 26 and a color ring 27 is provided on the outer periphery of the end portion. A ring 28 is attached.

  Further, a back-up ring 30, a rubber ring 33 (square rubber ring 32 and round rubber ring 31), a washer 34, and a push ring 29 are attached in this order adjacent to the back side of the polyethylene pipe 21 from the retaining ring 28. With each member mounted in this manner and the polyethylene pipe 21 being inserted into the mechanical joint portion 24, the bolt hole 23 a of the flange 23 and the bolt of the push wheel 29 are pushed so that the washer 34 is pushed by the rib portion of the push wheel 29. It is connected to the hole 29a by tightening with a nut 36 through a bolt 35 (see Patent Document 1).

  Further, as a conventional cap structure for closing the end portion of the polyethylene pipe 21, a fusion cap structure as shown in FIG. 7 is known. This cap structure has a receiving portion 37, and uses a cap member 39 provided with a heating wire 38 on the inner surface of the receiving portion 37, and inserts the end portion of the polyethylene pipe 21 inside the receiving portion 37, A voltage is applied to the lead wire 41 of the heat generating wire 38 drawn from the terminal portion 40 of the cap member 39 to fuse the cap member 39 to the end portion of the polyethylene tube 21 (see Patent Document 2).

JP-A-10-132168 JP-A-11-210978

  The mechanical joint structure described above has a connection target pipe (for example, a space for mounting a retaining ring 28 (lock ring 26, collar ring 27) on the outer periphery of the end of the polyethylene pipe 21, a backup ring 30, a rubber ring 33 (round). A space for arranging sealing members such as the rubber ring 31, the square rubber ring 32), the washer 34, etc. is required, so that the space required for connection from the pipe end of the pipe to be connected along the pipe axis becomes long and buried. In the case of pipes and the like, there are problems that time and labor are required for excavation, and good workability cannot be obtained due to the enlargement of the joint itself.

  On the other hand, the fusion cap structure as shown in FIG. 7 is used, for example, for temporary closing when the cast iron pipe 22 is replaced with the polyethylene pipe 21, and in this case, every time the replacement work proceeds. Then, the end portion of the polyethylene pipe 21 is cut and the fusion cap portion is discarded. According to this, time and labor are required for the fusion work of the fusion cap part, and the disposal of a large amount of waste generated as construction progresses becomes a problem.

  Accordingly, an object of the present invention is to shorten the connection space of the pipe end of the pipe to be connected and to reduce the size of the joint structure in a pipe joint structure including a cap member and a connection joint member connected to the pipe end. Pipe fittings for the purpose of improving connection work, improving workability in replacement work from cast iron pipes to polyethylene pipes, and obtaining a reusable cap structure without producing waste during construction. To provide a structure.

  The present invention has been made to achieve the above object, and is characterized by the following.

The invention according to claim 1 is a pipe joint structure in which a joint member is connected to an end portion of a connection target pipe, and includes first retaining means and second retaining means, and the first retaining means includes the first retaining means, A retaining member inserted into the pipe end of the connection target pipe and having a tooth portion formed on the outer peripheral surface thereof, and formed between the end inner peripheral surface of the joint member and the end outer peripheral surface of the connection target pipe. A sealing member to be inserted into the gap, and a pushing mechanism for pushing the sealing member to reduce the diameter of the connection target tube and thus biting the teeth into the inner peripheral surface of the connection target tube. The second retaining means includes a joint member side engaging portion formed in the joint member, and a retaining member side engaging portion formed on the retaining member and engaged with the joint member side engaging portion. It consists of a coupling portion, the coupling member side engagement portion, along the inner peripheral surface of the joint member The retaining member side engaging portions are formed at intervals along the inner peripheral surface of the retaining member, and the joint member side engaging portions are spaced apart by the retaining member. It is characterized by being formed wider than the width of the side engaging portion .

The invention according to claim 2 is the invention according to claim 1, wherein the tooth portion has an insertion side surface (S2) of the retaining member and an anti-insertion side surface (S1) of the retaining member. The angle (θ2) of the insertion side surface (S2) with respect to the axis (L) of the retaining member is the angle of the outer angle of the anti-insertion side surface (S1) with respect to the axis (L) of the retaining member ( It is characterized by being larger than θ1) .

The invention described in claim 3 is characterized in that, in the invention described in claim 1 or 2, the tooth portion is formed in a spiral shape around the axis of the retaining member .

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the push-in mechanism includes a push ring that contacts the sealing member, the push ring, and the joint member. It is characterized by comprising a bolt and a nut for fastening the nut .

The invention according to claim 5 is characterized in that, in the invention according to any one of claims 1 to 4 , a protrusion is formed on a surface of the retaining member that contacts the sealing member. It is what you have.

The invention according to claim 6 is the connection joint according to any one of claims 1 to 5, wherein the joint member connects an end of the connection target pipe and an end of the connection target pipe. It is characterized by being a member .

The invention according to claim 7 is characterized in that, in the invention according to any one of claims 1 to 5, the joint member is a cap member that closes an end of the pipe to be connected. is there.

The invention according to claim 8 is characterized in that , in the invention according to any one of claims 1 to 7, the sealing member is made of rubber .

The invention according to claim 9 is the invention according to any one of claims 1 to 8, wherein the connection object pipe is a resin pipe .

The invention according to claim 10 is the invention according to claim 9, wherein the resin pipe is a polyethylene pipe .

The invention described in claim 11 is the invention described in claim 6, wherein the connection target pipe is a metal pipe .

A twelfth aspect of the invention is characterized in that, in the invention of the sixth aspect, the connection target pipe is a resin pipe .

  According to the present invention, the sealing member is pushed in to reduce the diameter of the connection target pipe, the teeth of the retaining member are digged into the inner peripheral surface of the connection target pipe, and the joint member side engagement formed in the joint member is performed. By adopting a structure in which the joint portion and the retaining member side engaging portion formed on the retaining member are engaged, it is possible to reliably prevent the connection target tube from being detached, and to connect the outer peripheral surface of the connection target tube. Compared to the conventional pipe joint structure in which the retaining ring and the mechanical joint portion are arranged side by side, the length of the space required for connection along the pipe axis from the pipe end of the pipe to be connected can be shortened.

  In addition, unlike the conventional pipe joint structure, it is not necessary to arrange the retaining ring and the mechanical joint portion side by side on the outer peripheral surface of the connection target pipe, so that the length of the joint member can be shortened. As a result, the number of parts required for connection can be reduced and the joint structure can be miniaturized, so that the connection work of the pipe joint can be improved.

  Furthermore, when using the cap member having the structure of the joint member described above and closing the pipe end in the replacement work from the cast iron pipe to the polyethylene pipe, the cap structure can be reused without producing waste during construction. Can get.

It is sectional drawing which shows the pipe joint structure of this invention whose joint member is a connection joint member. It is A arrow directional view of FIG. It is A arrow directional view of FIG. 1 which shows the state which the retaining member side engaging part and the coupling member side engaging part are not engaging. It is the elements on larger scale of a retaining member. It is sectional drawing which shows the pipe joint structure of this invention whose joint member is a cap member. It is sectional drawing which shows the conventional joint structure. It is a fragmentary sectional view which shows the conventional cap structure.

  Next, an embodiment of the pipe joint structure of the present invention in which the joint member is a connection joint member will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a pipe joint structure according to the present invention, in which the joint member is a connection joint member, and FIG. 2 is a view taken along the arrow A in FIG.

  1 and 2, reference numeral 1 denotes a polyethylene pipe as a connection target pipe. The connection target pipe may be a resin pipe other than a polyethylene pipe. 2 is a connection joint member as a joint member. The connection joint member 2 connects the end of the polyethylene pipe 1 and the end of another polyethylene pipe 3 that is a connection target pipe. The pipe to be connected may be a metal pipe such as a cast iron pipe or a steel pipe in addition to the polyethylene pipe 3.

  Reference numeral 4 denotes first retaining means, which includes a retaining member 5, a sealing member 6, and a pushing mechanism 7.

  The retaining member 5 has a cylindrical shape and is inserted into the tube end portion of the polyethylene tube 1. At one end of the retaining member 5, a flange 5 a that contacts the tube end surface of the polyethylene tube 1 is formed, and at the outer peripheral surface of the retaining member 5, a tooth portion 5 b is formed in the circumferential direction. The outer diameter of the flange 5 a is larger than the outer diameter of the polyethylene pipe 1, and the sealing member 6 is brought into contact with the flange 5 a portion protruding from the outer peripheral surface of the polyethylene pipe 1. On the inner peripheral surface of the retaining member 5 on the flange 5a side, a retaining member-side engaging portion 5c is formed at an interval along the inner peripheral surface of the retaining member 5.

  The tooth portion 5b has a mountain-shaped cross section, and, as shown in FIG. 4, the angle (θ2) of the insertion side surface (S2) of the tooth portion 5b with respect to the axis (L) of the retaining member 5 is the anti-insertion side surface ( S1) is formed to be larger than the angle (θ1) of the outer angle with respect to the axis (L) of the retaining member 5. By forming in this way, it is easy to insert the retaining member 5 into the end portion of the polyethylene tube 1. On the other hand, as will be described later, the tooth portion 5 b becomes the inner peripheral surface of the polyethylene tube 1 due to the reduced diameter of the polyethylene tube 1. After biting into, the polyethylene pipe 1 can be reliably prevented from coming out.

  As shown in FIG. 4, if the apex angle (θ3) of the tooth portion 5 b is formed at an acute angle, the tooth portion 5 b easily bites into the inner peripheral surface of the polyethylene tube 1. Further improve.

  The tooth portions 5b are independently formed at intervals in the axial direction of the retaining member 5, but the tooth portions 5b may be formed in a spiral shape around the shaft of the retaining member 5. By making the tooth portion 5b into a spiral shape, when the retaining member 5 is inserted into the end portion of the polyethylene tube 1, for example, by striking the retaining member 5, even in a situation where the insertion is tight, instead of striking By inserting the retaining member 5 while rotating it, the spiral-shaped portion acts as a screw so that the retaining member 5 can be easily inserted. Moreover, when removing the retaining member 5, it can be easily removed by the action of a screw.

  In addition, as shown in FIG. 4, if the protrusion 5d is formed on the flange 5a surface of the retaining member 5 on the side in contact with the sealing member 6 described later, it is pushed into the sealing member 6 by the pressing mechanism 7 described later. When force is applied, the reaction force generated in the sealing member 6 by the protrusion 5d can be efficiently transmitted to the inner peripheral surface of the end portion of the connection joint member 2 and the outer peripheral surface of the end portion of the polyethylene pipe 1. As a result, the sealing performance is improved and the polyethylene pipe 1 can be reliably reduced in diameter. The protrusion 5d is preferably formed in an annular shape along the surface of the flange 5a.

  The sealing member 6 is made of a rubber ring, and is inserted into a gap (M1) formed between the end inner peripheral surface of the connection joint member 2 and the end outer peripheral surface of the polyethylene pipe 1. When the sealing member 6 is pushed into the inner part of the gap (M1) by the pushing mechanism 7, the pushing force causes the outer peripheral surface of the sealing member 6 to be constrained by the connecting joint member 2, so that the polyethylene pipe 1 is shrunk. It becomes the force to diameter. When the diameter of the polyethylene tube 1 is reduced, the tooth portion 5 b of the retaining member 5 bites into the inner peripheral surface of the polyethylene tube 1.

  The push-in mechanism 7 includes a push ring 8 that is in contact with the sealing member 6, a bolt 9 that fastens the push ring 8 and the connection joint member 2, and a nut 10 that is screwed into the bolt 9. The bolt 9 is inserted into a bolt hole 8 a formed in the push ring 8 and a bolt hole 2 a formed in the connection target pipe 2.

  11 is a second retaining means, the joint member side engaging portion 2b formed at the central portion in the axial direction of the connecting joint member 2 along the inner peripheral surface of the connecting joint member 2, and the above-mentioned , And a retaining member side engaging portion 5 c formed on the retaining member 5.

As shown in FIG. 2, the interval (L1) between the joint member side engaging portions 2b is formed wider than the width (L2) of the retaining member side engaging portion 5c. As a result, as shown in FIG. 3, the retaining member side engaging portion 5c is inserted between the joint member side engaging portions 2b , and the connecting joint member 2 is rotated counterclockwise by an angle (θ) in FIG. When rotated, the joint member side engaging portion 2b and the retaining member side engaging portion 5c overlap, and the joint member side engaging portion 2b and the retaining member side engaging portion 5c are engaged. As a result, the removal of the polyethylene pipe 1 from the connection joint member 2 can be reliably prevented in combination with the retaining effect by the first retaining means.

  According to the pipe joint structure of the present invention configured as described above, in which the joint member is a connection joint member, the connection joint member can be connected to the end of the polyethylene pipe as follows.

As shown in FIGS. 1 and 2, a push ring 8 and a sealing member 6 are attached to the outer periphery of the polyethylene pipe 1, and a retaining member 5 is inserted into the end of the polyethylene pipe 1. Next, the connection joint member 2 is fitted into the end portion of the polyethylene pipe 1 into which the retaining member 5 is inserted. At this time, the retaining member side engaging portion 5c is inserted between the joint member side engaging portions 2b , and the connecting joint member 2 is positioned where the joint member side engaging portion 2b and the retaining member side engaging portion 5c overlap. Until the joint member side engaging portion 2b and the retaining member side engaging portion 5c are engaged.

  Next, the sealing member 6 is inserted into the gap (M1) formed between the inner peripheral surface of the end portion of the connection joint member 2 and the outer peripheral surface of the end portion of the polyethylene pipe 1. Next, the bolt 9 is inserted into the bolt hole 8 a formed in the push wheel 8 and the bolt hole 2 a formed in the connection joint member 2, and the nut 10 is tightened. As a result, the sealing member 6 is pushed into the back of the gap (M1) formed between the inner peripheral surface of the end portion of the connection joint member 2 and the outer peripheral surface of the end portion of the polyethylene pipe 1. When the sealing member 6 is pushed in, the polyethylene tube 1 is reduced in diameter by the sealing member 6, and the tooth portion 5 b of the retaining member 5 bites into the inner peripheral surface of the polyethylene tube 1. As a result, even if a pull-out force acts on the polyethylene pipe 1, the teeth 5b of the retaining member 5 bite into the inner peripheral surface of the polyethylene pipe 1, so that the joint member side engaging portion 2a and the retaining member side engaging portion Combined with the engagement effect with 5c, it is possible to reliably prevent the polyethylene pipe 1 from coming off from the connection joint member 2.

  In this way, the connection joint member 2 can be connected to the end of the polyethylene pipe 1.

  The pipe to be connected connected to the polyethylene pipe 1 via the connection joint member 2 may be a metal pipe such as a cast iron pipe or an iron pipe in addition to the polyethylene pipe 3. Moreover, you may form the connection coupling member 2 in the edge part of a to-be-connected pipe | tube.

  According to the above-described pipe joint structure of the present invention in which the joint member is a connection joint member, the polyethylene pipe 1 is reduced in diameter by pushing the sealing member 6, and thus the retaining member on the inner peripheral surface of the polyethylene pipe 1. By adopting a structure in which the teeth 5b of 5 are bitten, the pipe end of the polyethylene pipe 1 is compared with the conventional pipe joint structure in which the retaining ring 28 and the mechanical joint portion 24 are arranged side by side on the outer peripheral surface of the polyethylene pipe 1. The length (L1) of the space required for connection along the tube axis can be shortened (see FIG. 1).

  In addition, the synergistic effect of the first retaining means 4 and the second retaining means 11 can surely prevent the polyethylene pipe 1 from coming off from the connection joint member 2.

  Further, unlike the conventional pipe joint structure (see FIG. 6), it is not necessary to arrange the retaining ring 28 and the mechanical joint portion 24 side by side on the outer peripheral surface of the connection target pipe, thereby reducing the number of parts required for connection, And the length of the connection coupling member 2 can be shortened. As a result, since the joint structure can be reduced in size, the connection work of the pipe joint can be improved.

  Next, an embodiment of the pipe joint structure of the present invention in which the joint member is a cap member will be described with reference to the drawings.

  FIG. 5 is a cross-sectional view showing the pipe joint structure of the present invention in which the joint member is a cap member.

  In FIG. 5, the same reference numerals as those in FIG. Reference numeral 12 denotes a cap member as a joint member, which closes the end of the polyethylene pipe 1. On the inner surface of the cap member 12, a cap member side engaging portion 12b corresponding to the joint member side engaging portion 2b in FIG. 1 is formed.

  The length (L2) of the cap member 12 is not required to arrange the retaining ring 28 and the mechanical joint portion 24 side by side on the outer peripheral surface of the connection target pipe as in the conventional pipe joint structure (see FIG. 6). Therefore, the cap member 12 can be reduced in size and weight. As a result, the workability of closing the polyethylene pipe 1 can be improved.

  The pipe joint structure of the present invention in which the joint member is a cap member can be effectively used, for example, in pipe replacement work in which an existing cast iron pipe is replaced with a polyethylene pipe. That is, in the pipe replacement work, it is necessary to close the end of the polyethylene pipe 1 at the time when the work of the day is completed. At this time, the pipe joint structure of the present invention is effectively used as follows. Can be used.

  A push ring 8 and a sealing member 6 are mounted on the outer periphery of a polyethylene pipe 1 newly provided by pipe replacement work, and a retaining member 5 is inserted into the end portion. Next, the cap member 12 is fitted into the end portion of the polyethylene pipe 1 into which the retaining member 5 is inserted. At this time, the retaining member side engaging portion 5c is inserted between the cap member side engaging portions 12b, and the connecting joint member 2 is positioned so that the cap member side engaging portion 12b and the retaining member side engaging portion 5c overlap. Until the cap member side engaging portion 12b and the retaining member side engaging portion 5c are engaged.

  Next, the sealing member 6 is inserted into a gap (M2) formed between the inner peripheral surface of the end portion of the cap member 12 and the outer peripheral surface of the end portion of the polyethylene pipe 1. Next, the bolt 9 is inserted into the bolt hole 8 a formed in the push ring 8 and the bolt hole 12 a formed in the cap member 12, and the nut 10 is tightened. As a result, the sealing member 6 is pushed into the back of the gap (M2) formed between the inner peripheral surface of the cap member 12 and the outer peripheral surface of the end portion of the polyethylene pipe 1. When the sealing member 6 is pushed in, the polyethylene tube 1 is reduced in diameter by the sealing member 6, and the tooth portion 5 b of the retaining member 5 bites into the inner peripheral surface of the polyethylene tube 1. As a result, even if a pull-out force acts on the polyethylene pipe 1, the teeth 5b of the retaining member 5 bite into the inner peripheral surface of the polyethylene pipe 1, so that the cap member side engaging portion 12b and the retaining member side engaging portion In combination with the engagement effect with 5c, the cap member 12 is not likely to come off from the polyethylene pipe 1, and the end of the polyethylene pipe 1 can be reliably closed.

  Further, since the cap member 12 is detachable from the polyethylene pipe 1 by removing the bolt 9, the cap member 12 can be reused. As a result, the problem of waste disposal caused by cutting the fusion cap portion in the prior art shown in FIG. 7 can be solved.

  According to the above-described pipe joint structure of the present invention in which the joint member is a cap member, the pipe end is closed in the replacement work from the cast iron pipe to the polyethylene pipe using the cap member 12 having the structure of the joint member. In some cases, a reusable cap structure can be obtained without producing waste during construction.

1: polyethylene pipe 2: connecting joint member 2a: bolt hole 2b: joint member side engaging portion 3: polyethylene pipe 4: first retaining means 5: retaining member 5a: flange 5b: tooth portion 5c: retaining member Joint part 5d: Protruding part 6: Sealing member 7: Pushing mechanism 8: Push ring 8a: Bolt hole 9: Bolt 10: Nut 11: Second retaining means 12: Cap member 12a: Bolt hole 12b: Cap member side engagement Joint 21: Polyethylene pipe 22: Cast iron pipe 23: Flange 23a: Bolt hole 24: Mechanical joint 25: Reinforcement material 26: Lock ring 27: Color ring 28: Retaining ring 29: Push ring 29a: Bolt hole 30: Backup ring 31: Round rubber ring 32: Square rubber ring 33: Rubber ring 34: Washer 35: Bolt 36: Nut 37: Receiving portion 38: Heating wire 39: Cap member 4 : Terminal section 41: the lead wire

Claims (12)

In a pipe joint structure in which a joint member is connected to an end of a connection target pipe, the pipe connection structure includes a first retaining means and a second retaining means, and the first retaining means is inserted into a pipe end of the connection target pipe. And a sealing member inserted in a clearance formed between the end inner peripheral surface of the joint member and the end outer peripheral surface of the connection target pipe. A member and a pushing mechanism that pushes the sealing member to reduce the diameter of the connection target tube, and thus bites the teeth into the inner peripheral surface of the connection target tube, and the second retaining means includes wherein the joint member side engagement portion formed on the joint member, which is formed on the retaining member consists of a the joint member side engagement portions that engage the retaining member side engagement portion, wherein the joint member The side engaging portion is formed at an interval along the inner peripheral surface of the joint member, The retaining member side engaging portion is formed with an interval along the inner peripheral surface of the retaining member, and the interval between the joint member side engaging portions is larger than the width of the retaining member side engaging portion. A pipe joint structure characterized by being widely formed . The tooth portion has an insertion side surface (S2) of the retaining member and an anti-insertion side surface (S1) of the retaining member, and the axis (L) of the retaining member of the insertion side surface (S2). 2. The pipe joint according to claim 1 , wherein an angle (θ2) of the outer angle with respect to is larger than an angle (θ1) of the anti-insertion side surface (S1) with respect to the axis (L) of the retaining member. Construction. The pipe joint structure according to claim 1, wherein the tooth portion is formed in a spiral shape around an axis of the retaining member . The push-in mechanism includes a push ring that comes into contact with the sealing member, and a bolt and a nut that fasten the push ring and the joint member. The pipe joint structure described in 1. The pipe joint structure according to any one of claims 1 to 4 , wherein a protrusion is formed on a surface of the retaining member that contacts the sealing member . The pipe joint according to any one of claims 1 to 5, wherein the joint member is a connection joint member that connects an end of the connection target pipe and an end of the connection target pipe. Construction. The pipe joint structure according to any one of claims 1 to 5, wherein the joint member is a cap member that closes an end of the pipe to be connected . The pipe joint structure according to any one of claims 1 to 7, wherein the sealing member is made of rubber . The pipe joint structure according to any one of claims 1 to 8, wherein the connection target pipe is a resin pipe . The pipe joint structure according to claim 9, wherein the resin pipe is a polyethylene pipe . The pipe joint structure according to claim 6, wherein the connection target pipe is a metal pipe . The pipe joint structure according to claim 6, wherein the connection target pipe is a resin pipe .

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