JP2018173147A - Temporary fixing structure of resin pipes - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temporary fixing structure of resin pipes which has a centering function and a drawing force at EF fusion, is reducible in a size of a clamp, excellent in economical efficiency, and disposable.SOLUTION: This temporary fixing structure 50 of resin pipes comprises an EF-joint 1 and a clamp 60. In the EF-joint 1, a heating wire 3h is incorporated into a fusion part M abutting on the resin pipe 5 which is fit into a receptacle 7, and at an external peripheral face of the receptacle 7, there are formed a first tapered part 44 which is formed so as to be narrowed as progressing toward an outer end side from a center side in a J-direction, a second tapered part 64 in which an engaged part 46 is formed, and which can abut on the first tapered part 44 at internal peripheral faces of a pair of halved holding parts 62A, 62B in the clamp 60, and an engagement part 66 which can be engaged with the engaged part 46.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a temporary fixing structure between resin tubes.

  Conventionally, thermoplastic resin pipes made of a resin such as polyethylene have been widely used for gas pipes, water pipes, drain pipes and the like because they have earthquake resistance, flexibility, and corrosion resistance. For the connection of thermoplastic resin pipes (hereinafter, sometimes simply referred to as “resin pipes”), an electric fusion joint is often used.

  Specifically, the electric fusion joint includes a joint body made of a thermoplastic resin, a heating element such as a heating wire embedded in a fusion interface on the inner peripheral side of the joint body, and a joint connected to the heating element. And a terminal portion having terminal pins standing on the outer surface of the main body. When joining resin pipes using an electric fusion joint, the power supply connected to the terminal pin with the resin pipe to be connected inserted into the receptacle provided at the end of the joint body of the electric fusion joint The heating element is heated by energizing the heating wire through the cord. Thereby, the resin on the inner peripheral surface of the receiving port around the heating element and the outer surface layer of each resin tube are melted, and the electrofusion joint and the resin tube are connected.

  As described above, when resin pipes are joined together using an electric fusion joint, the position and angle of the resin pipe to be joined during energization of the EF joint and the curing period of the fusion part are not shifted. A jig that can fix the relative positions of the resin tubes is required (see FIG. 1). An example of such a jig is a clamp.

  When the resin pipes are fixed to each other with a clamp using an electric fusion joint (hereinafter sometimes referred to as an EF joint), the pipes are so-called centered. If the resin pipes are electrofused without being centered, the resin pipes are joined obliquely, resulting in poor fusion, which is not preferable.

  As a clamp as described above, for example, Patent Document 1 discloses an EF joint clamp (clamp) including two upper and lower clamp members having substantially the same shape. Each clamp member includes a straight base, two arm portions extending at right angles from both ends of the base portion and having predetermined lengths different from each other, and a second arm portion extending at right angles inward from the tip of the arm portion. And a lever provided substantially at the center of the base. The clamp members are connected to each other by a hinge pin in the vicinity of the base of the lever, and a semicircular recess is formed in the arm portion and the second arm portion to hold a plastic tube having a predetermined diameter. Yes. The lever of the upper clamp member is provided with a clamping means capable of closing the two clamp members.

  Patent Document 2 discloses an EF joint clamp including a halved holding portion that sandwiches a connecting portion between a joint body and a resin pipe from the outside in the radial direction. A protruding pin is provided on the joint surface of one half holding portion 1A, and a female joint into which the protruding pin is fitted is provided on the joining surface of the other half holding portion. The projecting pin is inserted into the female joint and joined with the halved holding parts sandwiching the connecting portion, while the projecting pin is inserted into the female joint and the projecting pin moves in the pull-out direction. Is regulated.

JP-A-9-042553 JP2015-196260A

  However, since the clamp for EF joint disclosed in Patent Document 1 is made of metal such as aluminum, it is expensive and economically difficult to make disposable. Moreover, since the clamp for EF joints disclosed in Patent Document 1 is configured to grip the outer peripheral surfaces of the resin pipes on both sides of the EF joints, at least the dimension in the axial direction of the clamp is larger than that of the EF joints. Therefore, since it is large, there is also a problem that it is difficult to perform the construction in a narrow space.

  On the other hand, in the clamp for an EF joint disclosed in Patent Document 2, a constant pulling force (that is, a pulling force for pulling the resin pipe from the EF joint) with the outer peripheral surface of the connection portion between the resin pipe and the EF joint gripped. Therefore, since the dimension of the clamp along the axial direction is long and the rigidity is required, a force for fastening the resin pipe to the EF joint is required. Therefore, there has been a problem that it is difficult to perform construction in a narrow space. In addition, the EF joint clamp disclosed in Patent Document 2 has a problem that it is inferior in economic efficiency because the amount of resin used at the time of manufacture increases.

  The present invention has been made in view of the above circumstances, has a centering function and a pulling force at the time of EF fusion, can reduce the size of the clamp, is excellent in economy, and is a disposable resin. Provide a temporary fixing structure between tubes.

  The temporary fixing structure between the resin pipes according to the present invention is used at the time of electric fusion between the resin pipes, and is an electric fusion joint between the resin pipes and the clamps for temporarily fixing the resin pipes during energization and curing. An electric fusion joint having a plurality of receptacles into which the resin pipe can be fitted, and a connecting portion between the resin pipe fitted into the receptacle and the electric fusion joint is held from the outside in the radial direction. A clamp having a pair of halved holding portions configured to be capable of heating, and in the electric fusion joint, a heating wire is embedded in a fusion portion that abuts on the resin pipe fitted in the receptacle, and the receptacle A first tapered portion that is formed so as to narrow toward the outer end side from the center side in the axial direction of the electrofusion joint, and an engaged portion. Of the pair of halves The surface characterized in that it a second tapered portion which is contactable formed, said engagement engagement portion engaged portion formed on the first tapered portion.

  According to the above-described configuration, when the connection portion between the resin pipe and the electrofusion joint (EF joint) inserted into the receiving port at the time of electrofusion is held by the pair of halves of the clamp from the outside in the radial direction. The second taper portion comes into contact with the first taper portion, and the resin tubes can be easily centered. Further, the pulling force can be increased by engaging the engaging portion with the engaged portion. Therefore, the axial length of the clamp can be shortened and the clamp can be easily downsized. Moreover, since the electrofusion joint and the clamp are made of resin, they are excellent in economic efficiency and can be disposable.

  In the temporary fixing structure between the resin tubes described above, a bolt insertion portion or a screw hole is formed in each of the pair of half-holding portions, and the bolt is inserted into the bolt insertion portion and the bolt is stopped with a nut, Alternatively, by screwing a screw member into the screw hole, one half holding portion of the pair of half holding portions may be fixed to the other half holding portion.

  According to the above-described configuration, the pair of half-holding portions can be connected by bolts and nuts or screw members, so that the pair of half-holding portions can be easily and quickly connected by an electric drill or the like. .

  In the above-described temporary fixing structure between the resin tubes, the first tapered portion and the engaged portion are formed on the end side from the fusion portion without overlapping the fusion portion in the axial direction. May be.

  According to the above-described configuration, since the first tapered portion and the engaged portion are arranged in a so-called cold zone, the first tapered portion and the engaged portion need not be affected by the high temperature of the fused portion. Thus, it is possible to reliably prevent the first tapered portion and the second tapered portion from being joined together and the engaged portion and the engaging portion from being joined.

  According to the temporary fixing structure between the resin pipes according to the present invention, a centering function and a pulling force at the time of EF fusion can be obtained, the axial length of the clamp is shortened, and the outer diameter of the clamp is reduced. Can be made economical and can be made disposable.

It is a side view which shows the resin pipe connected using EF coupling. It is the partial sectional view seen from the side view and one side of one Embodiment of the temporary fixing structure of the resin pipes which concern on this invention. It is the fragmentary sectional view seen from the upper part of one embodiment of the temporary fixation structure of resin pipes concerning the present invention. It is a side view of one embodiment of the EF joint of the temporarily fixed structure of resin pipes concerning the present invention. It is a top view of one embodiment of a clamp of the temporary fixation structure of resin pipes concerning the present invention. It is a front view of one embodiment of a clamp of the temporarily fixed structure of resin pipes concerning the present invention.

  Hereinafter, an embodiment of a temporary fixing structure between resin tubes according to the present invention will be described with reference to the drawings. The drawings used in the following description are schematic, and the length, width, thickness ratio, and the like are not necessarily the same as the actual ones, and can be changed as appropriate.

  As shown in FIG. 2 to FIG. 4, a temporary fixing structure 50 between resin tubes (hereinafter sometimes simply referred to as “temporary fixing structure”) 50 according to an embodiment to which the present invention is applied is provided between resin tubes 5 and 5. This is a temporary fixing structure including an EF joint (electrical fusion joint) 1 and a clamp 60 that are used at the time of electrical fusion and temporarily fix the resin pipes 5 and 5 during energization and curing.

  The EF joint 1 is an EF joint that is connected by fusing at least a plurality (two in FIG. 2) of resin pipes 5 and 5 by heating, and includes a plurality of (two in FIG. 2) receiving ports 7 and 7. The resin-made joint main body 2 and the heating wire 3h embedded in the fusion part M of the receiving port 7 that contacts the resin pipe 5 fitted in each receiving port 7 are provided.

  The EF joint 1 is a socket, and includes a terminal portion 10 for performing fusion bonding with the resin pipes 5 and 5 and an indicator 13 in addition to the above-described configuration.

  The joint body 2 is a cylindrical member for internally fitting the resin pipes 5 and 5 to be connected. On the inner peripheral surface 2a side of the joint body 2, a heating wire 3h such as a nichrome wire is embedded. The heating wire 3h is wound spirally and continuously along the axial direction of the joint body 2 (that is, centering on the axial direction) so as to contact the inner peripheral surface 2a of the joint body 2. The heating wire 3h is not particularly limited as long as it includes a metal and can generate an induced current when a radio wave is irradiated from the outside of the EF joint 1.

  The fusion part M is a part that can be hotter than the surroundings when the heating wire 3h is wound and the heating wire 3h is energized.

  On the outer peripheral surface of the receiving port 7, a first tapered portion 44 formed so as to narrow in the radial direction from the center side of the joint body 2 toward the outer end side along the J direction, and an engaged portion 46 are formed. Has been. The first tapered portion 44 and the engaged portion 46 are formed over the entire circumferential direction of the outer peripheral surface of the receiving port 7. Although the inclination angle with respect to the J direction of the first tapered portion 44 is not particularly limited, it is preferably, for example, 15 ° or more and 75 ° or less from the viewpoint of sufficiently exerting the centering function of the temporary fixing structure 50.

  The first tapered portion 44 and the engaged portion 46 are formed in a so-called cold zone on the end side (that is, on both ends of the joint body 2) from the fused portion M without overlapping the fused portion M in the J direction. Has been. Further, the engaged portion 46 is formed on both ends of the joint body 2 with respect to the first tapered portion 44 in the J direction.

The engaged portion 46 is a groove recessed inward in the radial direction of the joint body 2. Although the depth from the outer peripheral surface 2b in the engaged portion 46 is not particularly limited, from the viewpoint of sufficiently exerting the pulling force of the temporary fixing structure 50, for example, when the outer diameter of the joint body 2 is D, 0.22 Dμm or more It is preferable that
A method for defining the minimum depth of the groove of the engaged portion 46 is, for example, as follows.
Tube dead weight = π · D (m) · t (m) · 5 (m) · 950 kgf / m ³
t = D / 11 (from SDR11) = 432πD ²
Shear force at groove depth h (m)> From tube weight 200 kgf / cm ² (PE shear) · π · D · h> 432πD ²
h (m)> 0.000216 D (m)
Therefore, the depth of the groove of the engaged portion 46 is preferably 0.22 Dμm or more.

  On the outer peripheral surface 2b of the joint body 2, there is formed a terminal portion 10 for attaching a cable connector of a fusion controller and allowing a current to flow through the heating wire 3h. The terminal portions 10 are respectively provided on the outer peripheral surfaces 2b on both end sides in the J direction (axial direction) of the joint body 2.

  The terminal portion 10 includes terminal pins 4 and a connector mounting portion 12. The terminal pin 4 projects from the outer peripheral surface 2 b of the joint body 2 toward the radially outer side of the joint body 2. Although not shown, the terminal pin 4 is connected to the end of the heating wire 3h.

  The connector mounting portion 12 is projected from the outer peripheral surface 2b of the joint body 2 toward the radially outer side of the joint body 2 so as to surround the terminal pin 4 with the terminal pin 4 as the center. Further, the connector mounting portion 12 is formed in a cylindrical shape, and is integrally formed on the outer peripheral surface 2b of the joint body 2 so that the terminal pins 4 and the center axis of each other are coaxially arranged.

  In the J direction, a concave portion 8 is formed in the outer peripheral surface 2b on the center side of the joint body 2 from the position where the terminal portion 10 is formed. The concave portion 8 is formed with a substantially cylindrical bar-shaped indicator 13 protruding from the bottom surface 8 a of the concave portion 8 toward the outer peripheral surface 2 b of the joint body 2. The indicator 13 can confirm that the inner peripheral surface 2a of the joint body 2 and the outer peripheral surface of the resin pipes 5 and 5 are properly fused at the time of the joining operation of joining the resin pipes 5 and 5 using the EF joint 1. It is provided to

  The joint body 2 and the resin pipe 5 are made of resin. Examples of the material of the joint body 2 and the resin pipe 5 include polybutene resin, high-density polyethylene resin, medium-density polyethylene resin, and polypropylene resin.

  The clamp 60 includes a pair of half-holding portions 62A and 62B configured to be able to hold the connecting portion X between the resin pipes 5 and 5 and the EF joint 1 fitted in the receiving ports 7 and 7 from the outside in the radial direction. ing. Specifically, the clamp 60 has a so-called cold zone portion on the end side from the fusion part M in the J direction of the joint body 2 (that is, both ends of the joint body 2), and the receptacle 7 side of the resin pipe 5. It is comprised so that a part can be hold | maintained.

  A second tapered portion 64 formed so as to be in contact with the first tapered portion 44 on each inner peripheral surface 62a of the pair of half-holding portions 62A and 62B, and an engagement engageable with the engaged portion 46 A portion 66 is formed. The inclination angle of the second tapered portion 64 with respect to the J direction is the same as the inclination angle of the first tapered portion 44 with respect to the J direction.

  The engaging portion 66 is a convex portion protruding inward in the radial direction of the half-holding portions 62A and 62B. The height of the engaging portion 66 from the inner peripheral surface 62a is the same as the depth of the engaged portion 46 from the outer peripheral surface 2b.

  As shown in FIGS. 5 and 6, a bolt insertion hole (bolt insertion portion) 72 is formed in each of the pair of half-holding portions 62 </ b> A and 62 </ b> B, and the bolt B is inserted into the bolt insertion hole 72 and a nut N is used. By stopping the bolt B, the half holding part (one half holding part) 62A can be fixed to the half holding part (the other half holding part) 62B.

  In the pair of half-holding portions 62A and 62B, a window portion 74 penetrating from the outer peripheral surface 62b to the inner peripheral surface 62a is formed. The window portion 74 is formed in an appropriate number at an appropriate position so that the insertion mark L can be seen when the connecting portion X between the resin pipes 5 and 5 and the EF joint 1 is held from the outside in the radial direction. (See FIG. 1). In the present embodiment, four window portions 74 are formed in the pair of half-holding portions 62A and 62B.

  As shown in FIG. 5, when the connection portion X between the resin pipes 5, 5 and the EF joint 1 is held from the outside in the radial direction, the pair of halved holding portions 62 </ b> A and 62 </ b> B has terminal portions of the EF joint 1. A recess 78 surrounding the terminal part 10 without colliding with the terminal 10 is formed. The concave portion 78 is a portion for allowing the terminal portion 10 to escape. By forming the recess 78, it is not necessary to lengthen the dimension along the J direction of the pair of half-holding portions 62A and 62B.

  As shown in FIG. 1 and the like, when the connection portion X is held from the outside in the radial direction in the pair of half-holding portions 62A and 62B, a plurality of portions along the J direction are held in the portions holding the resin tubes 5 and 5. The groove 80 is formed. By forming the plurality of grooves 80, slip resistance between the pair of half-holding portions 62 </ b> A and 62 </ b> B and the resin pipes 5 and 5 is increased, and the pulling force of the temporary fixing structure 50 is reinforced.

Next, a method for using the temporary fixing structure 50 of the present embodiment will be briefly described.
When joining the EF joint 1 and the resin pipes 5, 5 using the temporary fixing structure 50, first, the respective ends of the resin pipes 5, 5 are fitted into the receiving ports of the joint body 2. Subsequently, as shown in FIG. 1, the connecting portion X between the resin pipes 5, 5 and the EF joint 1 is sandwiched between the pair of half-holding portions 62 </ b> A and 62 </ b> B from the outside in the radial direction and tightened with bolts B and nuts N.

  Next, a cable connector of a controller (not shown) is attached to the pair of terminal pins 4, and the heating wire 3h is energized. When the heating wire 3h generates heat by energization, it is heated, the fusion part M becomes hotter than its surroundings, and the resin in the fusion part M is melted. Furthermore, by continuing energization to the heating wire 3h, the temperature rise of the fusion | melting part M reaches also the part which touches the fusion | fusion part M among the resin pipes 5, and the resin of the part also fuse | melts.

  When the fusion part M and the resin pipe 5 in contact with the fusion part M are fused and integrated, the energization to the heating wire 3h is stopped. Thereafter, a predetermined curing period (that is, resin cooling time) is set. The resin pipes 5 and 5 are connected using the EF joint 1 through the above-described steps.

  According to the temporary fixing structure 50 of the present embodiment described above, the connection portion X between the resin pipes 5 and 5 and the EF joint 1 inserted into the receiving ports 7 and 7 at the time of electrical fusion is connected to the clamp 60 from the outside in the radial direction. When held by the pair of halved holding portions 62A and 62B, the second taper portion 64 comes into contact with the first taper portion 44, and the first taper portion 44 and the second taper portion 64 function as a guide, so that the resin pipe Centering between 5 and 5 can be easily performed. Further, by engaging the engaging portion 66 with the engaged portion 46, it is possible to increase the pulling force that prevents the resin pipes 5 and 5 from being removed from the receiving ports 7 and 7. Therefore, it is possible to easily reduce the length of the clamp 60 in the J direction and reduce the size of the clamp 60. Moreover, since the EF joint 1 and the clamp 60 are made of resin, they are excellent in economic efficiency and can be made disposable.

  Further, according to the temporary fixing structure 50 of the present embodiment, since the bolt insertion holes 72 are formed in each of the pair of half-holding portions 62A and 62B, the pair of half-holding portions is formed by the bolt B and the nut N. 62A and 62B can be easily and quickly connected by an electric drill or the like.

  In addition, according to the temporary fixing structure 50 of the present embodiment, the first tapered portion 44 and the engaged portion 46 are arranged in a so-called cold zone, so the first tapered portion 44 and the engaged portion 46 are fused. It is not necessary to be affected by the high temperature of the part M, and the joining between the first tapered part 44 and the second tapered part 64 and the joining between the engaged part 46 and the engaging part 66 can be reliably prevented. .

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments, and various modifications are possible within the scope of the gist of the present invention described in the claims. Deformation / change is possible.

  For example, the pair of halved holding portions 62A and 62B may be configured to be fastened with a bolt B to a nut inserted into the clamp 60, and the bolt B is provided to a tap portion whose inner peripheral surface is threaded. You may be comprised so that clamping | tightening is possible.

  Further, the relationship between the convex portions and the grooves of the engaged portion 46 and the engaging portion 66 may be opposite to each other. That is, the engaged portion 46 is a convex portion that protrudes inward in the radial direction of the joint body 2, and the engaging portion 66 is a groove that is recessed outward in the radial direction from the inner peripheral surface 62 a of the half-holding portions 62 A and 62 B. There may be.

  Further, the clamp 60 may be made of metal and used as a jig for mounting the EF joint 1 and the resin pipes 5 and 5. In that case, the pair of half-holding portions 62A and 62B may be tightened by a hinge or a so-called patched lock.

DESCRIPTION OF SYMBOLS 1 ... EF coupling (electrical fusion joint), 44 ... 1st taper part, 46 ... Engaged part, 60 ... Clamp, 62 ... A pair of half holding | maintenance part, 64 ... 2nd taper part, 66 ... Engagement part

Claims (3)

It is used at the time of electric fusion between resin tubes, and is a temporary fixing structure between resin tubes consisting of an electric fusion joint and a clamp that temporarily fix the resin tubes together during energization and curing,
An electrofusion joint having a plurality of receptacles into which the resin pipe can be inserted; and
A clamp having a pair of half-holding portions configured to be able to hold the connecting portion between the resin pipe fitted into the receiving port and the electrofusion joint from the outside in the radial direction,
In the electric fusion joint,
A heating wire is embedded in the fused part that comes into contact with the resin pipe fitted in the receiving port,
On the outer peripheral surface of the receptacle, a first tapered portion formed so as to narrow toward the outer end side from the center side in the axial direction of the electrofusion joint, and an engaged portion are formed,
In the clamp,
A second taper portion formed so as to be able to contact the first taper portion and an engagement portion engageable with the engaged portion are formed on the inner peripheral surfaces of the pair of half-holding portions. A temporary fixing structure between resin tubes characterized by the above. A bolt insertion part or a screw hole is formed in each of the pair of half-holding parts,
By inserting a bolt into the bolt insertion portion and stopping the bolt with a nut, or by screwing a screw member into the screw hole, one half holding portion of the pair of half holding portions is connected to the other half. The temporary fixing structure between resin pipes according to claim 1, wherein the temporary fixing structure can be fixed to the split holding portion.   The said 1st taper part and the said to-be-engaged part are formed in the edge part side rather than the said melt | fusion part, without overlapping with the said melt | fusion part in the said axial direction. Item 3. A temporary fixing structure between resin pipes according to Item 2.

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