JP5978874B2 - Pipe covering layer folding jig - Google Patents

Description

  The present invention relates to a pipe covering layer turning jig for turning a covering layer in advance when connecting a pipe having a covering layer to a pipe connecting joint in a water supply system or a hot water supply system, for example.

  As a pipe for water supply or hot water supply, one having a coating layer on the outer peripheral surface of the pipe is known. This coating layer has a function of suppressing damage to the pipe and suppressing vibration and impact sound due to the water hammer phenomenon. When a pipe having such a coating layer is connected to a joint, the coating layer must be cut off at the end of the pipe or folded back.

  Various inventions for removing such a coating layer at the end of the pipe have been proposed. For example, Patent Document 1 discloses a piping method for a water supply / hot water supply pipe. That is, in the piping method, a peelable buffer layer is laminated on the outer periphery of the pipe, and a large number of protrusions extending in the longitudinal direction of the pipe are integrally formed on the buffer layer. It is something that strikes the layer.

  Patent Document 2 discloses a coating material peeling tool. This covering material peeling tool is provided with a cutting edge on a rotating main body and an extruding part for extruding the covering material peeled off by the cutting edge toward the outside of the main body.

JP 2000-303516 A JP-A-9-192901

  However, in the conventional water supply / hot water pipe arrangement method described in Patent Document 1, the buffer layer covering the outer periphery of the pipe has a certain thickness and strength, and the pipe is tightened from the periphery. There is a problem that it is not easy to fold the entire buffer layer by putting a finger on the ridge at the end of the ridge.

  On the other hand, the conventional coating material peeling tool shown in Patent Document 2 cuts off the coating material using a cutting blade extending in an oblique direction with respect to its axis, and the stripped coating material is removed at the extrusion section. It extrudes to the outside of the main body. For this reason, the covering material is cut off in an oblique direction with respect to the axis of the tool, and when the end of the tube is attached to the joint, there is a portion where the covering material is not formed on the outer periphery of the tube. Furthermore, with this covering material peeling tool, there is a possibility that the covering material cannot be sufficiently cut off when the cutting with the cutting blade is shallow, or the pipe may be damaged when the cutting with the cutting blade is deep. Therefore, this coating material peeling tool has a problem that it is not suitable as a tool for connecting the end portion of the pipe to the joint.

  Accordingly, an object of the present invention is to provide a pipe covering layer folding jig that can easily fold the coating layer at the pipe end and smoothly connect the pipe to the joint. is there.

  In order to achieve the above object, the pipe covering layer folding jig according to the first aspect of the present invention is a jig for folding the coating layer covering the outer peripheral surface of a cylindrical pipe at the end of the pipe. A cylindrical inner cylinder portion inserted between the pipe and the coating layer, and a cylinder surrounding the coating layer at the end of the pipe in a state where the inner cylinder portion is inserted between the pipe and the coating layer And a plurality of guide ribs projecting toward the inner cylinder portion are provided on the inner peripheral portion of the outer cylinder portion, and between the inner cylinder portion and the outer cylinder portion. An arcuate portion for folding is provided to guide the folding of the coating layer, and the inner cylinder portion is inserted between the pipe and the coating layer, and the coating layer is folded at the folding arcuate portion by pushing in while rotating. Features.

  The pipe covering layer folding jig according to claim 2 is the invention according to claim 1, wherein the guide rib is provided between the outer cylindrical portion and the inner cylindrical portion, and the folding arc-shaped portion is an inner periphery of the guide rib. It is provided in the part.

  The pipe covering layer folding jig according to claim 3 is the invention according to claim 2, wherein the folding arcuate portion is arranged such that the inner end side of the inner peripheral portion of the guide rib extends from the insertion side end portion of the inner cylinder portion. It is characterized by being cut out in a circular arc cross section.

  The pipe covering layer folding jig according to claim 4 is the invention according to any one of claims 1 to 3, wherein the guide rib has an inner cylinder portion side on an outer cylinder portion side with respect to a radial direction. It is characterized by being inclined so as to be positioned in the traveling direction of the rotation direction.

The pipe covering layer folding jig according to claim 5 is the invention according to claim 4, wherein an inclination angle of the guide rib is 20 to 40 ° with respect to a radial direction.
The pipe covering layer folding jig according to claim 6 is the invention according to any one of claims 1 to 5, wherein 5 to 7 guide ribs are provided at equal intervals in the circumferential direction. It is characterized by being.

  The pipe covering layer folding jig according to a seventh aspect of the present invention is the invention according to any one of the first to sixth aspects, wherein the outer peripheral surface of the inner cylinder portion is inserted from the inner back to the insertion side. It is formed in a taper shape so that it may reduce in diameter toward an end part.

  The pipe covering layer folding jig according to an eighth aspect of the present invention is the invention according to any one of the first to seventh aspects, wherein the jig is attached to the cylindrical portion of the handle, and at least the inner peripheral side of the guide rib is provided. It is configured to be visible from the outer end side of the handle.

According to the present invention, the following effects can be exhibited.
The pipe covering layer folding jig according to the present invention includes an inner cylinder portion inserted between the pipe and the covering layer, and an outer cylinder portion surrounding the covering layer at the end of the pipe in the inserted state of the inner cylinder portion. A plurality of guide ribs project from the inner peripheral portion of the outer cylindrical portion, and a folding arc-shaped portion that guides the folding of the coating layer is provided between the inner cylindrical portion and the outer cylindrical portion. Is provided. And an inner cylinder part is inserted between a pipe and a coating layer, and it pushes in rotating, and a coating layer is turned up by the arcuate part for folding.

  For this reason, the covering layer can be continuously folded by applying the folding jig to the end of the pipe and inserting the inner cylinder portion between the pipe and the covering layer and then pushing it in while rotating. . Therefore, the portion where the coating layer is folded and the pipe is exposed can be inserted and installed in the joint.

  Therefore, according to the jig for folding the pipe coating layer of the present invention, the coating layer at the pipe end can be easily folded, and the connection of the pipe to the joint can be performed smoothly.

The perspective view which shows the state which made the folding jig | tool in 1st Embodiment of this invention oppose the edge part of the resin pipe. (A) is the front view which shows the jig | tool for folding, (b) is sectional drawing which shows the jig for folding. The front view which shows the resin pipe which has a coating layer in an outer peripheral part. The expanded sectional view which shows the principal part of the jig | tool for folding. It is a figure which shows the effect | action which folds the coating layer of the resin pipe edge part, Comprising: (a) is sectional drawing which shows the state before applying the jig | tool for folding | fitting to a resin pipe, (b) is covering the inner cylinder part with a resin pipe Sectional drawing which shows the state inserted between the layers, (c) is sectional drawing which shows the state which reversed the coating layer, (d) is sectional drawing which shows the state which extended the folded coating layer to predetermined length. It is a figure which shows the effect | action which attaches the resin pipe by which the coating layer was folded back to a coupling, (a) is sectional drawing which shows the state which made the edge part of the resin pipe oppose the insertion space of a coupling, (b) Is a sectional view showing a state in which the resin pipe is inserted into the joint, and (c) is a sectional view showing a state in which the insertion of the resin pipe into the joint is completed. Sectional drawing which shows the jig | tool for folding | turning of 2nd Embodiment. The expanded sectional view which shows the principal part of the jig | tool for the return | turnback. (A) is a perspective view which shows the folding jig | tool of 3rd Embodiment, (b) is sectional drawing which shows the folding jig | tool. The partial expanded sectional view which shows the guide rib of the jig | tool for folding, and the arcuate part for folding. The perspective view which shows the handle | steering-wheel of the jig | tool for a return | turnback. The rear view of a handle | steering-wheel which shows the relationship between the 1st cylinder part of a handle | steering-wheel, the inner cylinder part of the jig | tool for folding | turning, a resin pipe, and a coating layer. Sectional drawing which shows the state which mounted | wore the folding jig | tool in the 2nd cylinder part of a handle | steering-wheel. It is a figure which shows the effect | action of a folding jig | tool, Comprising: (a) is a perspective view which shows the state which inserted the inner cylinder part of the folding jig | tool between the resin pipe and the coating layer, (b) is the state. FIG. FIG. 15 is an operation diagram following FIG. 14, in which (a) is a perspective view illustrating a state in which the coating layer starts to be folded back by the folding arc-shaped portion, and (b) is a cross-sectional view illustrating the state. FIG. 16 is an operation diagram following FIG. 15, where (a) is a perspective view showing a state in which the coating layer is being folded back by the folding arc-shaped portion, and (b) is a cross-sectional view showing the state. FIG. 17 is an operation diagram subsequent to FIG. 16, in which (a) is a perspective view showing a state in which the coating layer is folded and stacked on the coating layer of the resin pipe, and (b) is a cross-sectional view showing the state. Sectional drawing which shows the jig | tool for folding of another example of this invention. It is a figure which shows the jig | tool for folding of another example of this invention, Comprising: (a) is a perspective view of the folding jig which provided the protrusion for finger hooking on the outer peripheral surface, (b) is a finger hooking on the outer peripheral surface. The perspective view of the jig | tool for folding which provided the recessed part for operation.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.
As shown in FIG. 1, a folding jig 10 according to the first embodiment is a jig for folding a coating layer 12 covering an outer peripheral surface of a cylindrical resin pipe 11 at an end of the resin pipe 11. As shown in FIG. 3, a large number of protrusions 12 a extending in the longitudinal direction of the resin pipe 11 are formed at regular intervals in the circumferential direction on the inner peripheral surface of the covering layer 12. The resin pipe 11 is formed of a polyolefin resin such as a crosslinked polyethylene resin or a polybutene resin, and the coating layer 12 is formed of a thermoplastic elastomer such as an olefin thermoplastic elastomer.

  As shown in FIGS. 2A and 2B, the folding jig 10 includes a cylindrical inner cylinder portion 13 inserted between the resin pipe 11 and the coating layer 12, and the inner cylinder portion 13. Is integrally formed with a cylindrical outer cylinder portion 14 surrounding the coating layer 12 at the end of the resin pipe 11 in a state where the is inserted between the resin pipe 11 and the coating layer 12. The outer peripheral surface of the inner cylinder part 13 is a tapered surface 13a that is reduced in diameter toward the tip side. The inner cylinder part 13 is easily inserted between the resin pipe 11 and the coating layer 12, and the coating layer 12 is gradually removed. The diameter is increased. The folding jig 10 is formed of a synthetic resin such as an acrylic resin, a polypropylene (PP) resin, a polyethylene (PE) resin, or a polyacetal (POM) resin. A plurality (six in this embodiment) of guide ribs 15 projecting toward the inner cylinder part 13 are provided at regular intervals in the circumferential direction on the inner peripheral part of the outer cylinder part 14.

  It is desirable to provide 5 to 7 guide ribs 15 at equal intervals in the circumferential direction of the outer cylindrical portion 14. When the number of the guide ribs 15 is less than five, the force for guiding the folded covering layer 12A formed so as to be overlapped on the unfolded covering layer 12 is not preferable. On the other hand, when the number of the guide ribs 15 exceeds seven, the engagement force in the circumferential direction between the guide ribs 15 and the folded covering layer 12A tends to be strong, and it is difficult to continue the folding of the covering layer 12. It is not preferable.

  Further, as shown in FIG. 2A, the guide rib 15 is inclined so that the tip side thereof extends in the rotation direction of the folding jig 10 (counterclockwise direction in FIG. 2A). The inclination angle α of the guide rib 15 is desirably 20 to 40 ° with respect to the radial direction of the outer cylinder portion 14. When the inclination angle α of the guide rib 15 is less than 20 °, the sliding force of the guide rib 15 against the coating layer 12 tends to be strong, and it is difficult to smoothly fold the coating layer 12 due to wrinkles on the coating layer 12. It is not preferable. On the other hand, when the inclination angle α of the guide rib 15 exceeds 40 °, the sliding contact force of the guide rib 15 with respect to the coating layer 12 is reduced, and it becomes difficult to continuously fold the coating layer 12.

  As shown in FIGS. 2B and 4, a folding arcuate portion 16 for guiding the folding of the coating layer 12 is formed in an arcuate cross section between the inner cylinder portion 13 and the outer cylinder portion 14. Yes. The starting end portion of the folding arc-shaped portion 16 is smoothly connected to the tapered surface 13 a of the inner cylinder portion 13, and the terminal end portion is connected to the inner end portion of the guide rib 15 in a step shape. Then, as shown by the solid line and the alternate long and two short dashes line in FIG. 4, the inner cylinder portion 13 is inserted between the resin pipe 11 and the coating layer 12 and pushed in while rotating, whereby the coating layer 12 is turned back to the arcuate portion 16. The folded coating layer 12A obtained by folding is guided by the guide ribs 15 and overlapped on the coating layer 12 that is not folded.

Here, the joint into which the end of the resin pipe 11 with the covering layer 12 folded back is inserted will be briefly described.
As shown in FIG. 6 (a), the joint 20 is configured by providing a joint body 21 having a cylindrical shape for connecting the resin pipe 11 in three directions. The joint body 21 is formed of a synthetic resin such as polyphenylene sulfide resin (PPS). Since each joint main body 21 is the same structure, the one joint main body 21 is demonstrated.

  An inner cylinder 23 and an outer cylinder 24 for forming the insertion space 22 of the resin pipe 11 are formed on the joint body 21 so as to protrude from the inner periphery and the outer periphery. A spacer 25 is disposed in the outer cylinder 24, and a seal ring 26 is fitted on the outer peripheral surface of the inner cylinder 23. The inner space of the inner cylinder 23 is a flow path 27 through which a fluid such as water flows. A lid 28 is fitted to the outer peripheral surface of the outer cylinder 24.

  A retaining mechanism 29 for retaining the resin pipe 11 inserted into the insertion space 22 is provided between the outer cylinder 24 and the lid 28. A retaining ring 30 constituting the retaining mechanism 29 is formed with a plurality of retaining pieces protruding so as to incline toward the inner end side. In the insertion space 22, an insertion guide 31 that is pressed against the distal end surface of the resin pipe 11 and guides insertion of the resin pipe 11 is disposed. A fastening cover 32 is attached to the outer peripheral surface of the lid 28.

Next, the operation of the folding jig 10 configured as described above will be described.
Now, as shown in FIG. 5A, the guide rib 15 side of the folding jig 10 is opposed to the end of the resin pipe 11. Subsequently, as shown in FIG. 5B, the inner cylinder portion 13 of the folding jig 10 is inserted between the resin pipe 11 and the covering layer 12 and pushed straight. At this time, the end portion of the covering layer 12 enters the folding jig 10 while being expanded in diameter along the tapered surface 13 a of the inner cylinder portion 13, and reaches the folding arc-shaped portion 16. Next, as shown in FIG. 5 (c), when the folding jig 10 is pushed in while rotating counterclockwise in FIG. 2 (a), the tip of the covering layer 12 follows the arc of the folding arc-shaped portion 16. Then, it is smoothly reversed over the entire circumference and reaches the guide rib 15.

  Subsequently, as illustrated in FIG. 5D, when the operation of pushing the outer cylinder portion 14 while rotating is continued, the folded covering layer 12 </ b> A formed in an inverted manner is guided along the inner peripheral surface of the guide rib 15. The outer end of the guide rib 15 is reached, and further, the folding of the coating layer 12 proceeds continuously by sliding on the surface of the coating layer 12 where the folding coating layer 12A is not folded. In this way, at the end of the resin pipe 11, the coating layer 12 is folded back by a predetermined length, so that the end of the resin pipe 11 is exposed. The edge of the folded covering layer 12 </ b> A is formed in a direction perpendicular to the axis of the resin pipe 11. Further, the exposed amount of the end portion of the resin pipe 11 is determined by the insertion length inserted into the joint 20.

  Thereafter, the end of the resin pipe 11 in which the coating layer 12 is folded back by a certain length is connected to the joint 20. That is, as shown in FIG. 6A, the exposed portion of the end portion of the resin pipe 11 is opposed to the insertion space 22 of the joint 20. Subsequently, as shown in FIG. 6B, when the distal end portion of the resin pipe 11 is inserted into the insertion space 22 of the joint 20, the resin pipe 11 passes through the inner space of the lid body 28, and the distal end portion is inserted. Hit the guide 31. As shown in FIG. 6C, when the resin pipe 11 is further inserted into the insertion space 22 of the joint 20, the resin pipe 11 is guided by the insertion guide 31 and reaches the inner back of the insertion space 22. At this time, since the exposed amount of the resin pipe 11 is set in advance based on the insertion length into the joint 20, the folded portion of the coating layer 12 is in close contact with the outer end surface of the lid body 28 of the joint 20. Thus, in a state where the end of the resin pipe 11 is mounted in the insertion space 22 of the joint 20, the resin pipe 11 is retained by the retaining mechanism 29.

The effects obtained by the above first embodiment will be collectively described below.
(1) In the folding jig 10 of the first embodiment, a plurality of guide ribs 15 are provided on the inner peripheral portion of the outer cylindrical portion 14, and the folding is performed between the inner cylindrical portion 13 and the outer cylindrical portion 14. An arcuate portion 16 is provided. Then, the inner cylinder portion 13 is inserted between the resin pipe 11 and the coating layer 12, and the outer cylinder portion 14 is pushed in while rotating, so that the coating layer 12 is inverted by the folding arc-shaped portion 16, and the folding coating layer 12A is They are guided by the guide ribs 15 and overlapped on the coating layer 12.

  For this reason, after putting the folding jig 10 against the end of the resin pipe 11 and inserting the inner cylinder portion 13 between the resin pipe 11 and the coating layer 12, the coating layer 12 is pushed in while rotating. Can be quickly folded. Therefore, the portion where the coating layer 12 is folded and the resin pipe 11 is exposed can be easily inserted by being inserted into the joint 20.

Therefore, according to the folding jig 10 of the first embodiment, the coating layer 12 at the end of the resin pipe 11 can be easily and quickly folded with a simple jig, and the connection of the resin pipe 11 to the joint 20 can be performed. There is an effect that it can be performed smoothly.
(2) The guide rib 15 is inclined so that the tip side thereof extends in the rotation direction of the outer cylinder portion 14. For this reason, when the inner cylindrical portion 13 of the folding jig 10 is inserted between the resin pipe 11 and the coating layer 12 and rotated, the guide rib 15 is easily engaged with the folding coating layer 12A, and the folding coating layer 12A is It can guide favorably and the folding of the coating layer 12 can be effectively advanced.
(3) The inclination angle α of the guide rib 15 is set to 20 to 40 ° with respect to the radial direction of the outer cylinder portion 14. Therefore, the covering layer 12 can be folded most effectively.
(4) Five to seven guide ribs 15 are provided at equal intervals in the circumferential direction of the outer cylinder portion 14. Therefore, the engagement between the guide rib 15 and the folded covering layer 12A can be performed at the most appropriate interval in the circumferential direction of the outer cylinder portion 14, and the folding of the covering layer 12 can be continued in a stable state.
(5) The folding arc-shaped portion 16 is formed in a circular arc shape in cross section. Accordingly, the end of the covering layer 12 can be folded back smoothly and promptly along the arc of the folding arcuate portion 16.
(Second Embodiment)
Next, a second embodiment embodying the present invention will be described with reference to FIGS. In the second embodiment, parts different from the first embodiment will be mainly described.

  As shown in FIGS. 7 and 8, the guide rib 15 is formed with a flat portion 15a having an inner peripheral edge extending from the terminal end portion of the folding arc-shaped portion 16 in the tangential direction of the arc to be flat. . For this reason, as shown in FIG. 8, the folded covering layer 12 </ b> A inverted in the arc shape along the folded arc-shaped portion 16 is configured to move straight along the flat portion 15 a of the guide rib 15 as it is. Yes.

  Now, when the covering layer 12 positioned at the end of the resin pipe 11 is folded, as shown by the solid line in FIG. 8, the inner cylindrical portion 13 of the folding jig 10 is connected between the resin pipe 11 and the covering layer 12. The tip of the coating layer 12 is inserted into the folding jig 10 along the tapered surface 13 a of the inner cylinder portion 13. Thereafter, as shown by a two-dot chain line in FIG. 8, when the folding jig 10 is pushed in while being rotated, the end portion of the covering layer 12 is reversed along the arc of the folding arc-shaped portion 16. The reversed folded covering layer 12A moves straight from the terminal end of the folded arcuate portion 16 directly to the outer end side through the flat portion 15a. Therefore, the folded covering layer 12A moves in the tangential direction of the arc at the time of folding and is pushed out to the outer end side as it is.

Therefore, according to the second embodiment, the movement of the folded covering layer 12A after the front end portion of the covering layer 12 is folded can be performed more smoothly than in the case of the first embodiment. Can be efficiently performed.
(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, the description will focus on the parts different from the first embodiment.

  As shown in FIGS. 9A and 9B, the guide rib 15 is constructed between the inner peripheral portion of the outer cylindrical portion 14 and the outer peripheral portion of the inner cylindrical portion 13. An arcuate portion 16 for folding having an arcuate cross section is provided. The size of the arc of the folding arc-shaped portion 16 is set in consideration of the thickness, material, and the like of the coating layer 12 of the resin pipe 11. A pair of chamfered portions 19 are provided on the outer peripheral surface of the outer cylindrical portion 14 at positions facing each other by 180 degrees. The distance D between the outer cylindrical portion 14 and the inner cylindrical portion 13 between the guide ribs 15 is such that when the coating layer 12 is folded back by the folding arc-shaped portion 16, the coating layer 12 positioned between the guide ribs 15 is Sufficient length is secured so as not to hit the inner peripheral surface and cause resistance when folded.

  As shown in FIG. 10, the folding arc-shaped portion 16 is notched in a cross-sectional arc shape from the insertion side end portion of the inner cylinder portion 13 on the inner end side (left end side in FIG. 10) of the inner peripheral portion of the guide rib 15. Is formed. In this case, the inner peripheral side of the folding arcuate portion 16 is formed along the tapered surface 13 a of the inner cylinder portion 13, that is, the tapered surface 13 a extends in a substantially tangential direction of the folding arcuate portion 16. In addition, a chamfered surface 16 a having a circular arc cross section is formed at the opening end of the folding arc-shaped portion 16, so that the covering layer 12 can be smoothly guided to the folding arc-shaped portion 16. And when the insertion side edge part of the inner cylinder part 13 is inserted between the resin pipe 11 and the coating layer 12, it is comprised so that the coating layer 12 may be immediately folded along the arcuate part 16 for folding.

  As shown in FIGS. 11 and 12, the handle 40 for facilitating the operation of the folding jig 10 is formed in a substantially bottomed hexagonal cylinder shape by a synthetic resin such as ABS resin, and the handle is formed at the center of the handle 40. A cylindrical first tube portion 41 extending in the axial direction of 40 is provided. A cylindrical second cylindrical portion 43 is formed concentrically on the outer peripheral portion of the first cylindrical portion 41 so as to extend longer than the first cylindrical portion 41 at a predetermined interval. A pair of cut surfaces 45 are formed on the inner peripheral surface of the second cylindrical portion 43 at positions facing each other by 180 degrees.

  Then, as shown in FIGS. 12 and 13, the folding jig 10 is fitted inside the second cylindrical portion 43, and the back surface thereof comes into contact with the inner end surface of the first cylindrical portion 41. As shown in FIG. 14A, when the folding jig 10 is fitted into the second cylindrical portion 43, the pair of chamfered portions 19 of the folding jig 10 is a pair of cut surfaces of the second cylindrical portion 43. 45, and the rotation of the folding jig 10 is restricted. As shown in FIG. 12, the first cylinder portion 41 of the handle 40 is formed larger than the inner cylinder portion 13 and the outer peripheral portion of the folding jig 10, and as shown by a two-dot chain line in FIG. The inner cylinder portion 13 of the folding jig 10 is inserted between the outer cover surface 12 and the covering layer 12 so that the state of folding the covering layer 12 can be visually recognized from the outer end surface (back surface) of the handle 40.

  As shown in FIG. 11, a plurality of finger hanging recesses 47 are provided on the outer peripheral surface of the peripheral wall 46 of the handle 40, and the turning operation of the folding jig 10 can be performed by putting a finger on the finger hanging recesses 47 and turning it. It can be easily done. A plurality of reinforcing ribs 48 extending in a radial manner are provided between the first tube portion 41 and the second tube portion 43 and between the second tube portion 43 and the peripheral wall 46.

Next, the operation of the folding jig 10 of the third embodiment will be described.
Now, as shown in FIGS. 14A and 14B, when the coating layer 12 at the end of the resin pipe 11 is folded back, the folding jig 10 is fitted into the second cylindrical portion 43 of the handle 40, and the outer end surface thereof is fitted. Is pressed against the inner end surface of the first tube portion 41. At this time, the chamfered portion 19 of the folding jig 10 is engaged with the cut surface 45 of the second cylindrical portion 43, so that the relative rotation between the folding jig 10 and the handle 40 is restricted.

  In a state where the folding jig 10 is fitted to the handle 40, the folding jig 10 is opposed to the end surface of the resin pipe 11, and the inner cylinder portion 13 is inserted between the resin pipe 11 and the coating layer 12. At this time, since the outer peripheral surface of the inner cylinder portion 13 of the folding jig 10 is a tapered surface 13a whose diameter decreases from the inner back portion toward the insertion side end portion, the inner cylinder portion 13 is connected to the resin pipe 11. And the cover layer 12 can be easily inserted, and the cover layer 12 can be gradually separated from the resin pipe 11 and guided to the folding arc-shaped portion 16 of the guide rib 15.

  As shown in FIGS. 15A and 15B, when the handle 40 is grasped and the folding jig 10 is pressed against the end surface of the resin pipe 11, the resin pipe 11 is rotated clockwise toward the end surface. The covering layer 12 starts to be folded along the folding arcuate portion 16, and at the same time, the resin pipe 11 is inserted inside the inner cylinder portion 13. At this time, since the folding arc-shaped portion 16 of the folding jig 10 is cut out in a circular arc shape from the insertion side end of the inner cylinder portion 13, the covering layer 12 of the resin pipe 11 is formed in the inner cylinder portion 13. Is inserted between the resin pipe 11 and the covering layer 12, and immediately expands along the arcuate portion 16 for folding.

  As shown in FIGS. 16A and 16B, when the handle 40 is rotated so that the folding jig 10 is further pressed against the end surface of the resin pipe 11, the covering layer 12 of the resin pipe 11 becomes the folding jig. At the same time, the resin pipe 11 is inserted deeply into the inner cylinder portion 13 while being folded back into a semicircular cross section along the folding arc-shaped portion 16. At this time, the size of the arc of the folding arc-shaped portion 16 is appropriately set, and the guide rib 15 is arranged such that the inner circumferential portion is positioned on the rotational direction side of the folding jig 10 with respect to the radial direction than the outer circumferential portion. Therefore, the covering layer 12 can be folded back smoothly with a small force.

  As shown in FIGS. 17A and 17B, when the rotation operation of the handle 40 is continued, the coating layer 12 of the resin pipe 11 is completely folded back to form the folded coating layer 12A, and the folded coating layer 12A is The outer periphery of the resin pipe 11 is formed so as to overlap the unfolded coating layer 12. At this time, since the guide ribs 15 of the folding jig 10 are provided at six locations at equal intervals in the circumferential direction, the entire coating layer 12 of the resin pipe 11 is folded evenly. In this way, the coating layer 12 of the resin pipe 11 can be easily and quickly turned back by a predetermined length from the end of the resin pipe 11 as compared with the first and second embodiments.

In addition, each said embodiment can also be changed and actualized as follows.
As shown in FIG. 18, in the first embodiment or the second embodiment, the inner cylinder portion 13 of the folding jig 10 is configured so that the tip portion thereof becomes an inclined portion 13 b having a predetermined inclination angle. May be. In this case, it is possible to more easily insert the distal end portion of the inner cylinder portion 13 between the resin pipe 11 and the covering layer 12 as compared with the above embodiments.

  As shown in FIG. 19A, in the first embodiment or the second embodiment, a finger hooking protrusion extending in the axial direction of the outer cylinder portion 14 on the outer peripheral surface of the outer cylinder portion 14 of the folding jig 10 A plurality of 17 may be provided in the circumferential direction. Further, as shown in FIG. 19B, a plurality of finger catching recesses 18 extending in the axial direction of the outer cylinder portion 14 may be provided in the circumferential direction on the outer peripheral surface of the outer cylinder portion 14. In these cases, it is possible to increase the rotational force when the outer cylinder portion 14 is gripped with a finger and rotated in the circumferential direction.

  In the first embodiment or the second embodiment, the height, width, and length of the guide rib 15 are appropriately changed according to the thickness, material, and diameter of the resin pipe 11 of the coating layer 12 of the resin pipe 11. Also good.

-In said 1st-3rd embodiment, you may comprise the circular arc of the arcuate part 16 for folding | turning so that the starting end side (inner peripheral side) may be small diameter, and the terminal end side may become large diameter gradually.
The inclination direction of the guide rib 15 is set in the direction opposite to that in the first to third embodiments, and the covering jig 12 is turned back by rotating the turning jig 10 in the direction opposite to that in each embodiment. May be.

In the third embodiment, the folding arc-shaped portion 16 of the folding jig 10 may be formed in a circular arc shape at a position slightly on the outer end side from the inner end side of the inner peripheral portion of the guide rib 15.
-In 3rd Embodiment, you may form the arcuate part 16 for folding | turning of the jig | tool 10 for folding | folding in the shape of a vertically long or horizontally long cross-sectional elliptical arc.

  In the third embodiment, when the folding jig 10 is mounted in the second cylindrical portion 43 of the handle 40, the folding jig 10 is controlled from the handle 40 by restricting the movement of the folding jig 10 in the axial direction. A restricting member for preventing detachment may be provided on the handle 40.

In the third embodiment, one or three or more chamfered portions 19 of the folding jig 10 and corresponding cut surfaces 45 of the handle 40 may be provided.
The folding jig 10 may be formed of a synthetic resin (engineering plastic) such as polyacetal (POM), polyphthalamide (PPA), or polyphenylsulfone (PPSU).

As the pipe, in addition to the resin pipe 11, a soft metal pipe such as a copper pipe may be used.
The joint 20 can be configured such that the joint body 21 is two-way, four-way, or the like.

  DESCRIPTION OF SYMBOLS 10 ... Folding jig | tool, 11 ... Resin pipe, 12 ... Covering layer, 12A ... Folding coating layer, 13 ... Inner cylinder part, 13a ... Tapered surface, 14 ... Outer cylinder part, 15 ... Guide rib, 15a ... Flat part, 16 ... an arcuate part for folding, 40 ... a handle, 43 ... a second cylindrical part, α ... an inclination angle.

Claims (8)

A jig for folding the coating layer covering the outer peripheral surface of the cylindrical pipe at the end of the pipe,
A cylindrical inner cylinder portion inserted between the pipe and the coating layer, and a cylindrical outer cylinder surrounding the coating layer at the end of the pipe with the inner cylinder portion inserted between the pipe and the coating layer The cylindrical portion is integrally formed, and a plurality of guide ribs projecting toward the inner cylindrical portion are provided on the inner peripheral portion of the outer cylindrical portion, and a covering layer is provided between the inner cylindrical portion and the outer cylindrical portion. A folding arc-shaped portion for guiding folding is provided, the inner cylinder portion is inserted between the pipe and the coating layer, and the coating layer is folded at the folding arc-shaped portion by being pushed in while rotating. A jig for turning the pipe coating layer. 2. The pipe covering layer folding treatment according to claim 1, wherein the guide rib is provided between the outer cylinder part and the inner cylinder part, and the arcuate part for folding is provided on the inner peripheral part of the guide rib. Ingredients. 3. The pipe covering layer according to claim 2, wherein the folding arc-shaped portion is formed by notching the inner end side of the inner peripheral portion of the guide rib in a circular arc shape from the insertion side end portion of the inner cylinder portion. Folding jig. 4. The guide rib according to claim 1, wherein the guide rib is disposed so as to be inclined with respect to the radial direction so that the inner cylinder portion side is positioned in the traveling direction in the rotational direction relative to the outer cylinder portion side. The pipe covering layer folding jig according to the item. The pipe covering layer folding jig according to claim 4, wherein an inclination angle of the guide rib is 20 to 40 ° with respect to a radial direction. 6. The pipe covering layer folding jig according to claim 1, wherein 5 to 7 guide ribs are provided at equal intervals in the circumferential direction. The inner cylinder part is formed in a taper shape so that an outer peripheral surface thereof is reduced in diameter from an inner back part toward an insertion side end part, according to any one of claims 1 to 6. The jig for folding the pipe coating layer as described. The pipe according to any one of claims 1 to 7, wherein the pipe is mounted in a cylindrical portion of the handle so that at least an inner peripheral side of the guide rib can be visually recognized from an outer end side of the handle. Jig for folding the coating layer.