JP2020028197A - Corrugated pipe - Google Patents

Abstract

To provide a corrugated pipe having good bending workability while ensuring the shape stability of an overlapped portion of the corrugated pipe and projecting the tip of the overlapped portion to the outer periphery of the pipe without damaging peripheral parts and the like.SOLUTION: In a corrugated pipe 1, a plurality of peaks 3 and troughs 5 extending in the circumferential direction are alternately formed in the pipe axis direction at predetermined intervals. Further, in a cross section perpendicular to the longitudinal direction of the corrugated pipe, the respective peaks 3 and troughs 5 of an inner overlapping portion 7a and an outer overlapping portion 7b provided at both ends in the circumferential direction of the corrugated pipe 1 can be overlapped. A step portion 13 is provided on the outer peripheral side of the connection portion between the inner overlapping portion 7a and a curved connection portion 9 in the circumferential direction. The height of the outer peripheral surface of the peak 3 of the inner overlapping portion 7a in the step portion 13 is formed to be lower than the outer peripheral surface of the peak 3 of the other portion of the inner overlapping portion 7a.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a corrugated pipe that has an opening that is continuous in the longitudinal direction and that can be closed by overlapping overlapping parts near the opening end.

  Conventionally, when laying an electric wire or the like, the electric wire or the like is inserted into a protective tube such as a corrugated tube. Since the corrugated pipe is tubular, it is necessary to sequentially feed the electric wires from the ends in order to insert the electric wires into such a tubular member. However, this was not always easy.

  On the other hand, there is a method in which a slit is formed in a part of the corrugated tube along the longitudinal direction to form an opening, and an electric wire is inserted through the opening. In this case, there is no need to feed the electric wire in the longitudinal direction, so that the workability is good.

  Conventionally, as such a corrugated pipe, a corrugated pipe having only a slit in the longitudinal direction has been used.However, when a large amount of wire is inserted or when the corrugated pipe is bent and used, a slit portion is formed. Since the mouth opened, the tape was wound around the outer periphery of the corrugated pipe to prevent the mouth from opening. However, the corrugated pipe wound with the tape has problems that the workability is deteriorated and the cost is increased.

  As such a corrugated pipe, for example, a corrugated pipe in which peaks and valleys are repeatedly formed in a pipe axis direction and an inner overlapping portion and an outer overlapping portion are overlapped and used in a circumferential direction has been proposed. (Patent Document 1).

  Further, a rib connecting the peaks along the pipe axis direction is formed at the valley of the inner overlapping portion, and the rib formed at the valley of the inner overlapping portion is a valley of the outer overlapping portion. There has been proposed a corrugated pipe formed to have a size that can be stored in a rib formed in a portion (Patent Document 2).

  Further, a corrugated pipe in which annular protrusions and annular recesses are alternately formed along the longitudinal direction has been proposed (Patent Document 3). The corrugated pipe of Patent Document 3 is provided on a corrugated tube body with a lock receiving portion provided on one side edge across a slit, and a lock receiving portion provided on the other side edge. An enlarged diameter portion including a lock piece to be fitted.

  Further, a crack-protected annular protective sheath having a slot and a longitudinal tongue has been proposed (Patent Document 4). The annular protective sheath of U.S. Pat. No. 6,037,045 is separated into two groove edges by a continuous longitudinal slot. The tongue is substantially a groove cavity formed at one edge of the slot and can be located at the other slot edge. The groove is closed off by the longitudinally formed wall at the level of both edges of the slot by the groove edge wall. Also, the tongue remains below the edge on the other side and is flat, and the thickness of the tongue is substantially equal to the thickness of the groove hollow or the wall of the annular tube. Also, the groove edge wall is inclined and oriented outward.

  In addition, a corrugated tube has been proposed that has improved flexibility while having a plate-shaped wrap portion and that can easily accommodate a wire harness or the like (Patent Documents 5 and 6). In the corrugated tubes of Patent Documents 5 and 6, a plate-shaped lap portion projecting from one edge sandwiching a slit provided along the axial direction of the tube main body overlaps the inner peripheral side of the other edge. Can be In addition, an end of each protruding ridge that is overlapped with the plate-shaped lap is cut out to form an opening.

  Further, a corrugated pipe in which peaks and valleys are formed repeatedly in the pipe axis direction and the inner fitting part and the outer fitting part are overlapped and fitted in the circumferential direction, and the wave of the overlapped part is used. The wall thickness of the part is smaller than the wall thickness of the curved connection part side, the width of the inner overlapping part gradually decreases in diameter toward the tip of the inner overlapping part, and the outer fitting part and the inner fitting part There has been proposed a corrugated pipe that is fitted by fitting (Patent Document 7).

JP 2017-175802 A JP 2017-198257 A JP-A-2015-162955 JP 2000-505533 A JP-A-2002-369331 JP-A-2002-369332 JP 2001-509241 A

  However, in the corrugated pipe of Patent Literature 1, the overlap between the outer overlap portion and the inner overlap portion is insufficient, and the outer overlap portion may protrude more than necessary from the inner overlap portion. Alternatively, there is a possibility that the inner overlapping portion does not fit in the predetermined position, and the tip of the inner overlapping portion protrudes from the overlapping portion, protrudes into the corrugated pipe, and damages the electric wire accommodated in the corrugated pipe. Thus, the corrugated pipe of Patent Document 1 has a problem that the shape of the overlapping portion is not stable.

  Further, in the corrugated pipe of Patent Literature 2, the ribs are formed in the pipe axis direction, so that the fitting structure between the inner overlapping portion and the outer overlapping portion is stable. Is bent, so that there is a problem in that the presence of a rib reduces the flexibility.

  Further, the corrugated pipe of Patent Document 3 has a complicated shape and is difficult to process. At the same time, since the bottom of the lock receiving portion into which the tip of the lock piece fits is formed continuously in the longitudinal direction, there is a problem that when bent, a whitened portion is formed at this portion and the portion is broken. In addition, even if the whitened portion does not immediately break when formed, if the corrugated pipe having the whitened portion is attached to the vehicle, the whitened portion is broken due to vibration fatigue during running of the vehicle. High risk and cannot be put to practical use.

  Further, in the annular protective sheath with a crack in Patent Document 4, since a groove edge wall is formed at the end of the groove, the bendability of the corrugated pipe is reduced by this wall, and the tongue is used for the corrugated pipe. Bending may cause whitening. Further, when the corrugated pipe is used in a bent state, the tongue may protrude inward and damage the internal electric wires.

  Further, in the corrugated tubes of Patent Documents 5 and 6, it is necessary to simultaneously cut the vicinity of the end of each ridge and the end of the plate-shaped lap portion in order to form an opening at the end of each ridge. is there. For this reason, considering the manufacturing variation of the tube main body before cutting by blow molding, there is a problem that manufacturing is difficult and the plate-shaped lap portion is whitened during bending.

  On the other hand, there is a method in which a plate-shaped wrap having a plurality of cuts formed along the circumferential direction of the tube main body is formed along the axial direction of the slit. In this case, since the wrap is divided into a plurality of cuts along the axial direction, even when the corrugated pipe is bent, whitening does not occur, but the shape is complicated and the opening at the end of each ridge is not required. There is a problem that it is difficult to cut to form slabs and productivity is poor.

  Further, as described in Patent Document 7, the corrugated pipe is formed such that the inner fitting portion and the outer fitting portion are in close contact with each other, as described that the inner fitting portion and the outer fitting portion can be welded after fitting. You. At this time, when the wiring is inserted into the corrugated pipe and bending is performed, the rigidity is different between the portion where the inner overlap portion and the outer overlap portion are in close contact and the curved connection portion where the overlap portion does not exist. Occurs. For this reason, when the corrugated pipe is bent, there is a problem that the opening and flattening of the corrugated pipe occur and the bending workability of the corrugated pipe is poor. Further, when the corrugated pipe is used in a bent state, the inner overlapping portion projects inward and the outer overlapping portion projects outward, and there is a risk of damaging internal wires and external components.

  The present invention has been made in view of such a problem, and while ensuring the shape stability of the overlapping portion of the corrugated pipe, the tip of the overlapping portion protrudes to the outer circumference of the pipe, or protrudes to the inner circumference of the pipe. It is an object of the present invention to provide a corrugated pipe having good bending workability without damaging peripheral parts and the like.

  In order to achieve the object described above, the present invention provides a corrugated pipe in which a plurality of peaks and valleys extending in a circumferential direction are alternately formed in a pipe axis direction at predetermined intervals and alternately formed in a pipe circumferential direction. An overlap having an opening continuous in the axial direction, wherein, in a cross section perpendicular to the longitudinal direction of the corrugated pipe, the crests and the valleys of the corrugated pipe overlap with each other at both circumferential ends of the corrugated pipe. A mating portion, and a curved connecting portion connecting the overlapping portions at both ends, wherein the overlapping portion arranges an outer overlapping portion on an outer peripheral side of an inner overlapping portion, and each of the overlapping portions It is possible to close the pipe by overlapping the peaks and the valleys, and the curved connection portion and the inner overlapping portion are formed with the peaks or the valleys continuously, Curved At the connecting portion between the connecting portion and the inner overlapping portion, a step portion is formed in which the outer peripheral side of the connecting portion is rapidly reduced in diameter, and the height of the outer peripheral portion of the peak portion of the inner overlapping portion at the step portion is Is formed lower than other portions of the inner overlapping portion.

  The height of the ridge near the tip of the outer overlapping portion decreases toward the tip of the outer overlapping portion, and when the inner overlapping portion and the outer overlapping portion overlap, the outer It is desirable that the tip of the overlapping portion be disposed near the step.

  The outer overlapping portion has substantially the same height as the curved connecting portion except for a tip portion of the outer overlapping portion, and a connection between the curved connecting portion and the outer overlapping portion. In the vicinity of the portion, a protruding portion protruding toward the inner peripheral side of the curved connection portion is formed, and in a cross section perpendicular to the longitudinal direction of the corrugated pipe, the protruding portion and the curved connection portion are smoothly connected. Is desirable.

  In the vicinity of the distal end portion of the outer overlapping portion, a large-diameter portion and a small-diameter portion formed on the distal end side of the large-diameter portion are formed in two steps, and in a cross section perpendicular to the longitudinal direction of the corrugated pipe, the large-diameter portion has a large diameter. At the distal end of the diameter portion, an oblique wall facing the small diameter portion side is provided, and a circumferential end of the small diameter portion is opened, or a reduced diameter portion that gradually reduces the diameter from the large diameter portion is provided. The circumferential end of the reduced diameter portion may be opened.

  The height of the outer peripheral surface of the ridge of the inner overlapping portion is formed lower than the inner peripheral surface of the ridge of the outer overlapping portion, and when the overlapping portions are overlapped, A gap is formed between the inner peripheral surface of the ridge of the outer overlapping portion and the outer peripheral surface of the ridge of the inner overlapping portion, and the circumferential end of the small diameter portion of the outer overlapping portion or The clearance at the circumferential end of the reduced diameter portion may be smaller than the clearance at another portion of the outer overlapping portion.

  In a cross section of the corrugated pipe in the longitudinal direction of the pipe axis, the width of the outer peripheral surface of the ridge of the inner overlapping portion is smaller than the width of the inner peripheral surface of the ridge of the outer overlapping portion, It is preferable that a gap is formed between the ridges of the outer overlapping portion and the inner overlapping portion when the overlapping portions are overlapped.

  At the tip of the valley at the end of the cross section in the circumferential direction of the inner overlapping portion, a curved portion or a straight portion is formed obliquely so that the tip of the valley does not protrude in the inner circumferential direction. It is desirable. The tip of the inner overlapping portion increases the height of the peaks and valleys to secure the stability of the overlap. For this reason, the height of the valley near the front end of the inner overlapping portion is increased so as to protrude toward the inner peripheral side. By forming a chamfered portion by chamfering the protrusion, burr can be prevented.

  In the vicinity of the tip of the crest at the end of the circumferential section of the outer overlapping portion, a curved portion or a straight portion is formed diagonally so that the tip of the crest does not protrude in the outer peripheral direction. Is also good.

  In the vicinity of the tip of the circumferential section of the inner overlapping portion or the outer overlapping portion of the corrugated pipe, a curved shape formed so that the corner of the tip of the valley or the peak of the tip does not project. The portion or the straight portion may be either an R chamfer or a C chamfer directed in the outer circumferential direction or the inner circumferential direction.

  When the corrugated pipe is bent in the longitudinal direction with the overlapping portion facing the outer side of the bent portion, the tip of the outer overlapping portion and the fitting position of the inner overlapping portion are different from each other in the inner overlapping portion. By moving from the step portion side to the tip portion side of the inner overlapping portion, the outer overlapping portion does not protrude outward, and the outer overlapping portion and the inner overlapping portion after bending are bent. The gap may be smaller.

  A hinge part may be arranged on at least a part of the curved connection part.

  According to the present invention, the step portion is formed at the connection portion between the curved connection portion and the inner overlapping portion, and the height of the outer peripheral surface of the peak portion of the inner overlapping portion at the step portion is different from that of the inner overlapping portion. It is formed lower than the site. For this reason, when the outer overlapping portion of the corrugated pipe is overlapped with the inner overlapping portion, the elastic repulsive force from the inner overlapping portion is reduced near the tip of the outer overlapping portion, and the overlapping portion of the corrugated pipe is reduced. Shape stability is ensured, and it is possible to prevent the tip of the outer overlapping portion from protruding toward the outer periphery of the pipe, thereby damaging peripheral components.

  Also, the inner overlapping portion is formed by gradually decreasing the height of the crest from the vicinity of the tip of the inner overlapping portion toward the step portion to the outer periphery near the tip of the outer overlapping portion. Height is also reduced. For this reason, when the outer overlapping portion of the corrugated pipe is overlapped with the inner overlapping portion, the overlapping portion is easily fitted, so that the shape of the overlapping portion of the corrugated pipe is stabilized, and the outer overlapping portion is secured. It is possible to prevent the tip of the overlapping portion from projecting to the outer periphery and damaging peripheral components.

  Furthermore, by gradually lowering the height of the outer peripheral surface of the ridge portion of the outer overlapping portion from the tip portion of the inner overlapping portion toward the step portion, the tip portion of the outer overlapping portion is overlapped with the inner overlapping portion. When combined, the outer overlapping portion can be smoothly guided to the step portion. Further, after the tip of the outer overlapping portion reaches the step portion, the movement of the outer overlapping portion is prevented by the step portion formed in the inner overlapping portion, and further entry is prevented. For this reason, when the corrugated pipes are overlapped, the tip of the outer overlapped portion is arranged near the step of the inner overlapped portion, so that the shape can be stabilized.

  Also, except for the tip portion of the outer overlapping portion, if the height of the peak portion of the outer overlapping portion is substantially the same as the height of the peak portion of the curved connection portion, the outer periphery of the corrugated pipe has a circumferential direction. No irregularities or steps are formed, and external damage and the like can be suppressed. At this time, by forming a protruding portion that protrudes on the inner peripheral side of the curved connecting portion near the connecting portion between the curved connecting portion and the outer overlapping portion, the tip of the inner overlapping portion is located closer to the outer peripheral side than the protruding portion. And is protected by a protrusion. That is, even if the tip of the inner overlapping portion protrudes toward the inner circumference of the pipe, it is possible to prevent the inner electric wire from being damaged. At this time, the shape of the protrusion may be a gentle curve.

  In addition, by reducing the height of the peak near the tip of the outer overlapping portion toward the tip of the outer overlapping portion, the tip of the outer overlapping portion more reliably projects to the outer periphery of the pipe. , And damage to peripheral components can be suppressed, and the outer overlapping portion can be more reliably arranged on the outer periphery of the inner overlapping portion. Further, by opening the front end of the outer overlapping portion, the opening can be made smaller, and the intrusion of dust and other foreign matter from the outside can be prevented.

  Also, when the inner overlapping portion and the outer overlapping portion are overlapped, the tip of the outer overlapping portion is arranged near the step portion of the inner overlapping portion so that the overlapping portion is directed to the outer peripheral side of the bent portion. When bent so as to have a curvature along the longitudinal direction, the fitting position between the tip of the outer overlapping portion and the inner overlapping portion is shifted from the step portion side of the inner overlapping portion to the tip of the inner overlapping portion. Move to the side. On the other hand, when the overlapping portion is bent toward the inner peripheral side of the bent portion, the fitting position is restrained by the step portion of the inner overlapping portion and does not move any further, so that the corrugated pipe is securely stacked. The overlapping shape of the parts can be maintained.

  In addition, a large-diameter portion and a small-diameter portion are formed in two steps in the vicinity of the front end portion of the outer overlapping portion, and an oblique wall is provided on the front end side of the large-diameter portion toward the small-diameter portion, and the circumferential direction of the small-diameter portion is provided. By opening the end portion, it is possible to more reliably suppress the tip of the outer overlapped portion from protruding to the outer periphery of the pipe, and suppress damage to peripheral components. At this time, instead of forming the large-diameter portion and the small-diameter portion in two steps, a reduced-diameter portion is formed to form an oblique wall so that the diameter is gradually reduced from the large-diameter portion. The part may be opened.

  Further, the oblique wall provided on the tip side of the large-diameter portion of the outer overlapping portion allows the opening at the tip of the outer overlapping portion to be made smaller, so that intrusion of dust and other foreign matter from the outside can be prevented. .

  Also, when the overlapping portions are overlapped, a gap is formed between the inner peripheral surface of the crest of the outer overlapping portion and the outer peripheral surface of the crest of the inner overlapping portion, and the small diameter portion of the outer overlapping portion is formed. The leading end is opened, and the gap between the circumferential end of the opening and the inner overlapping portion is made smaller than the gap of the other portion of the outer overlapping portion, or the diameter of the reduced diameter portion is gradually reduced from the large diameter portion. The top end or the end of the reduced diameter portion is opened, and the gap between the circumferential end portion of the opening and the inner overlapping portion is formed smaller than the gap of the other portion of the outer overlapping portion. And the stability of the leading end fitting portion when bent can be improved.

  Also, by reducing the gap between the outer overlapping portion tip opening and the inner overlapping portion, and further reducing the height of the step portion of the inner overlapping portion, the height of the outer overlapping portion can also be reduced. In the case of overlapping, it is possible to prevent dust and other foreign substances from entering from outside without impairing stabilization of the fitting portion.

  Similarly, by forming a gap between the ridges of the outer overlapping portion and the inner overlapping portion in the width direction when the overlapping portion is overlapped, stabilization and bending of the fitting after the overlapping are performed. Flexibility at the time of pressing can be improved.

  In addition, the tip of the valley in the circumferential cross-sectional end of the inner overlapping portion is provided with a chamfered portion formed in a curved or straight shape so that the inner diameter of the tip near the tip is enlarged. More reliably, it is possible to suppress the pointed portion of the inner overlapping portion from protruding toward the inner circumference of the tube, and to prevent the internal electric wire or peripheral components from being damaged.

  In the vicinity of the tip of the crest at the end of the circumferential section of the tip of the outer overlapping portion, in the form of a curve or a straight line directed inward so that the tip of the crest does not protrude outward. By providing the formed chamfered portion, it is possible to suppress damage to external electric wires or components.

  The chamfered portion provided on the outer overlapping portion or the chamfered portion provided in the vicinity of the tip of the inner overlapping portion has a R-chamfer or a C-chamfer directed inward or outward in a section perpendicular to the longitudinal direction of the corrugated pipe. It can be either.

  When the corrugated pipe is bent with the overlapping portion facing the outer periphery of the bent portion, the fitting position between the tip of the outer overlapping portion and the inner overlapping portion is shifted from the step portion side of the inner overlapping portion to the inner overlapping portion. By moving to the tip side of the joining portion and reducing the gap between the tip of the outer overlapping portion after bending and the inner overlapping portion, it is possible to suppress the outer overlapping portion from projecting outward. it can.

  Further, by arranging the hinge portion at a part of the curved connection portion, the opening and closing operation of the corrugated pipe is easy.

  ADVANTAGE OF THE INVENTION According to this invention, while ensuring the shape stability of the superposition part of a corrugated pipe, the front-end | tip of a superposed part protrudes to the outer periphery of a pipe, and it does not damage peripheral parts etc. Can be provided.

FIG. 2 is a plan view showing the corrugated pipe 1. FIG. 2 is a cross-sectional view showing the corrugated pipe 1, and is a cross-sectional view taken along line AA of FIG. (A) is an enlarged view of a part B of FIG. 2, and (b) is an enlarged view of a part C of FIG. FIG. 2 is a plan view showing the corrugated pipe 1 in a closed state. FIG. 5 is a cross-sectional view showing the corrugated pipe 1 in a closed state, and is a cross-sectional view taken along line HH of FIG. 4. (A) is an enlarged view of a part I in FIG. 5, and (b) is a view showing another embodiment of the outer overlapping portion 7b. FIG. 5 is a sectional view showing the corrugated pipe 1 in a closed state, and is a sectional view taken along line GG of FIG. 4. The K section enlarged view of FIG. (A) is a sectional view taken along line LL of FIG. 8, (b) is a sectional view taken along line MM of FIG. 8, (c) is a sectional view taken along line NN of FIG. 8, and (d) is a sectional view. FIG. 9 is a sectional view taken along line OO of FIG. 8.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing the corrugated pipe 1, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1 (a cross-sectional view perpendicular to the longitudinal direction of the corrugated pipe 1), and FIG. 3B is an enlarged view of a portion C of FIG. 2, and FIG. 3B is an enlarged view of a portion C of FIG.

  In the corrugated pipe 1, a plurality of peaks 3 and troughs 5 extending in the circumferential direction are alternately formed in the pipe axis direction at predetermined intervals. In the following description, the outer peripheral portion of the corrugated tube 1 of the corrugated tube 1 is referred to as a mountain portion 3, and the inner peripheral portion of the corrugated tube of the corrugated tube 1 is referred to as a valley portion 5. The surface of the corrugated pipe 1 when viewed from the outer side of the ridges 3 and the valleys 5 is the outer peripheral surface of the ridges 3 and the valleys 5 respectively. The side viewed from the side) is the inner peripheral surface of each of the peak 3 and the valley 5.

  The corrugated pipe 1 has an opening 11 that is continuous in the pipe axis direction in a pipe circumferential section. That is, the opening 11 is formed continuously in the pipe axis direction of the corrugated pipe 1. Further, in a cross section perpendicular to the longitudinal direction of the corrugated pipe 1, at both ends in the circumferential direction of the corrugated pipe 1, there are provided overlapping portions 7 where the peaks 3 and the valleys 5 of the corrugated pipe 1 overlap each other. One side of the overlapping portion 7 is an inner overlapping portion 7a, and the other side is an outer overlapping portion 7b.

  A curved connecting portion 9 is formed between the inner overlapping portion 7a and the outer overlapping portion 7b of the corrugated pipe 1. That is, the curved connecting portions 9 are portions that connect the inner overlapping portion 7a and the outer overlapping portion 7b provided at both ends in the circumferential direction of the corrugated pipe 1.

  The overlapping portion 7 of the corrugated pipe 1 is configured such that the outer overlapping portion 7b is arranged on the outer peripheral side of the inner overlapping portion 7a, and the ridge portions 3 and the valley portions 5 of the overlapping portion 7 are overlapped to form a pipe. It is possible to close. The details of the closed state of the corrugated tube 1 will be described later.

  As shown in FIG. 2, the height of the peak 3 of the outer overlapping portion 7b is substantially the same as the height of the peak 3 of the curved connecting portion 9 except for the tip of the outer overlapping portion 7b. That is, at the boundary between the outer overlapping portion 7b and the curved connection portion 9, no step is formed on the outer peripheral side.

  Further, a protruding portion 15 protruding toward the inner peripheral side of the curved connection portion 9 in the inner peripheral portion of the curved connection portion 9 and near the connection portion between the curved connection portion 9 and the outer overlapping portion 7b. It is formed. The protruding portion 15 is a portion formed on the inner peripheral portion of the valley portion 5 and formed so as to protrude toward the inner peripheral side so that the inner diameter is smaller than other portions. In the cross section perpendicular to the longitudinal direction of the corrugated pipe 1, the protruding portion 15 and the curved connection portion 9 are smoothly connected.

  As shown in FIG. 3A, in the vicinity of the distal end of the outer overlapping portion 7b, a large-diameter portion 19 and a substantially linear small-diameter portion 21 formed on the distal end side of the large-diameter portion 19 are provided in two stages. It is formed.

  In addition, the height of the outer peripheral surface of the ridge 3 near the tip of the outer overlapping portion 7b decreases toward the tip of the outer overlapping portion 7b. More specifically, in a circumferential cross section perpendicular to the longitudinal direction of the corrugated pipe 1, an oblique wall 20 whose diameter decreases toward the small diameter portion 21 is provided at the distal end side of the large diameter portion 19. That is, a curved portion or a straight portion is formed obliquely in the vicinity of the tip of the peak 3 in the circumferential cross section of the outer overlapping portion 7b so that the tip of the peak 3 does not protrude in the outer peripheral direction. . For example, the curved portion or the straight portion formed so that the tip portion of the peak portion 3 does not protrude is either R chamfering or C chamfering toward the outer peripheral direction.

  As shown in FIG. 2, in a state where the outer overlapping portion 7b and the inner overlapping portion 7a abut each other, the inner peripheral surface of the valley portion 5 of the outer overlapping portion 7b is formed inside the valley portion 5 of the inner overlapping portion 7a. It is located outside the peripheral surface. That is, in the vicinity of the abutting portion of the outer overlapping portion 7b and the inner overlapping portion 7a, the distance between the center of the curved connecting portion 9 and the inner peripheral surface of the valley 5 of the outer overlapping portion 7b is larger than that of the curved connection. The distance from the center of the portion 9 to the inner peripheral surface of the valley portion 5 of the inner overlapping portion 7a is smaller.

  As shown in FIG. 1, the peaks 3 or the valleys 5 are formed in the inner overlapped portion 7 a in the circumferential direction from the curved connection portion 9. That is, also at the boundary between the curved connecting portion 9 and the inner overlapping portion 7a, a plurality of peaks 3 and valleys 5 are repeatedly formed in the tube axis direction. The width of the outer peripheral surface of the ridge 3 in the inner overlapping portion 7a is larger than the width of the inner peripheral surface of the ridge 3 of the outer overlapping portion 7b and the width of the inner peripheral surface of the ridge 3 of the curved connection portion 9. Is also narrow.

  As shown in FIG. 3B, a step portion 13 in which the outer peripheral side of the connecting portion sharply reduces in diameter in the circumferential direction is provided on the outer peripheral side of the connecting portion between the inner overlapping portion 7 a and the curved connecting portion 9. Provided. In the step portion 13, the outer peripheral surface height of the peak portion 3 of the inner overlapping portion 7 a is formed lower than the outer peripheral surface height of the peak portion 3 of the curved connection portion 9. Further, the height (D in the figure) of the outer peripheral portion of the peak portion 3 of the inner overlapping portion 7a in the step portion 13 is the height of the outer peripheral portion of the peak portion 3 (E in the drawing) of the other portion of the inner overlapping portion 7a. ). In the illustrated example, a portion where the height of the outer peripheral surface of the mountain portion 3 gradually decreases from the tip end side of the inner overlapping portion 7a toward the step portion 13 is formed. In addition, the height of the outer peripheral surface of the peak portion 3 may be reduced stepwise from the tip side of the inner overlapping portion 7a toward the step portion 13.

  Further, as shown in FIG. 3A, in a cross section perpendicular to the longitudinal direction of the corrugated pipe 1, the inner surface near the front end of the inner overlapping portion 7a is directed outward so that the inner diameter is enlarged. A chamfer 23 is formed. That is, a curved portion or a straight portion is formed obliquely at the tip of the valley 5 in the circumferential cross section of the inner overlapping portion 7a so that the tip of the valley 5 does not protrude in the inner circumferential direction. . The chamfered portion 23 is formed such that the inner diameter of the inner peripheral portion of the valley portion 5 gradually increases. For example, the chamfered portion 23 is one of an R chamfer and a C chamfer directed in the inner circumferential direction or the outer circumferential direction in a cross section perpendicular to the longitudinal direction of the corrugated pipe 1. The chamfered portion 23 can prevent the pointed portion of the valley 5 of the inner overlapping portion 7a from projecting in the inner circumferential direction of the pipe.

  Next, a method for manufacturing the corrugated pipe 1 will be described. FIG. 2 is a sectional view showing the corrugated pipe 1. Although not shown, the corrugated pipe is a pipe body in a state before manufacturing the corrugated pipe 1 according to the present invention, and in a state before the opening 11 formed in the corrugated pipe 1 is formed. is there. That is, the corrugated pipe 1 forms the opening 11 by cutting the cutting portion 17 with a blade, and the corrugated pipe has the same structure as the corrugated pipe 1 except for the vicinity of the opening 11.

  The corrugated tube is manufactured by, for example, blow molding after extrusion. For example, a resin is extruded into a cylindrical shape from an extruder to form a cylindrical material. In addition, the mold is repeatedly transferred and supplied while synchronizing the transfer speed of the mold set in the endless track with the extrusion speed of the tubular material.

  The tubular material is formed by being sandwiched between a pair of molds. The mold is a half-split half-cylinder member having irregularities formed on the inner surface according to the outer shape of the corrugated tube. When the pair of dies face each other and are joined together, a cylindrical member is formed, and ridges and valleys corresponding to the outer shape of the corrugated pipe are formed on the inner surface.

  The corrugated pipe is a generally tubular member having no opening along the longitudinal direction. In the corrugated pipe, a plurality of peaks 3 and valleys 5 extending in the circumferential direction are alternately formed in the pipe axis direction at predetermined intervals.

  In the corrugated pipe, the tip of the inner overlapping portion 7a and the tip of the outer overlapping portion 7b are connected. It is cut between the tip of the inner overlapping portion 7a and the tip of the outer overlapping portion 7b. The corrugated pipe 1 having the opening 11 can be manufactured by cutting the cut portion 17 of the corrugated pipe at a predetermined position with a blade or the like.

  As described above, in the state where the outer overlapping portion 7b and the inner overlapping portion 7a abut against each other, the inner peripheral surface of the valley portion 5 of the outer overlapping portion 7b has a valley portion of the inner overlapping portion 7a. 5 is located outside the inner peripheral surface. For this reason, the outer peripheral surface of the peak 3 (large-diameter portion 19) of the outer overlapping portion 7b is located outside the outer peripheral surface of the peak 3 of the inner overlapping portion 7a. Therefore, a step is formed on the outer surface of the abutting portion between the peak 3 (the large-diameter portion 19) on the outer overlapping portion 7b side and the peak 3 of the inner overlapping portion 7a.

  Next, a method of using the corrugated pipe 1 will be described. As described above, in the cross section perpendicular to the longitudinal direction of the corrugated pipe 1, the overlapping portion 7 has the outer overlapping portion 7b disposed on the outer peripheral side of the inner overlapping portion 7a, and the respective peak portions 3 and the valley portions 5 are provided. It is possible to close the tubes one on top of the other.

FIG. 4 is a plan view showing the corrugated pipe 1 in a closed state. FIG. 5 is a sectional view taken along line HH of FIG. 4, and FIG. 6A is an enlarged view of a portion I of FIG.
That is, FIGS. 5 and 6A are cross-sectional views perpendicular to the longitudinal direction of the corrugated pipe 1 at the peak 3. FIG. 7 is a sectional view taken along line GG of FIG. 4, and FIG. 8 is an enlarged view of a portion K in FIG. That is, FIGS. 7 and 8 are cross-sectional views of the valley 5 perpendicular to the longitudinal direction of the corrugated pipe 1.

  As described above, in each of the inner overlapping portion 7a and the outer overlapping portion 7b, the peak portions 3 and the valley portions 5 are alternately formed. Further, the inner peripheral surface size of the ridge 3 of the outer overlapping portion 7b is larger than the outer peripheral surface size of the ridge 3 of the inner overlapping portion 7a. That is, the height of the outer peripheral surface of the ridge 3 of the inner overlapping portion 7a is formed lower than the inner peripheral surface of the ridge 3 of the outer overlapping portion 7b. The inner peripheral surface of the valley 5 of the outer overlapping portion 7b is formed to be larger than the outer peripheral surface of the valley 5 of the inner overlapping portion 7a.

  Accordingly, the corrugated pipe 1 can reduce the diameter of the curved connection portion 9 and overlap the respective peak portions 3 and valley portions 5 of the inner overlapping portion 7a and the outer overlapping portion 7b. In this way, the corrugated pipe 1 can be closed.

  Here, when the inner overlapping portion 7a and the outer overlapping portion 7b are overlapped, the tip of the outer overlapping portion 7b is arranged near the step 13 of the inner overlapping portion 7a. That is, the opening at or near the distal end of the small diameter portion 21 of the outer overlapping portion 7b is near the step 13 of the inner overlapping portion 7a and near the base of the inner overlapping portion 7a (the curved connecting portion 9). (In the vicinity of the boundary portion with).

  Note that, instead of the substantially linear small-diameter portion 21 formed on the distal end side of the large-diameter portion 19, a reduced-diameter portion that gradually reduces in diameter from the large-diameter portion 19 toward the distal end may be used. FIG. 6B is a diagram illustrating the outer overlapping portion 7b in which the reduced diameter portion 24 is formed. The reduced diameter portion 24 is formed so as to continuously decrease in height from the large diameter portion 19. Note that the reduced diameter portion 24 may be formed so that the height gradually decreases.

  In any case, the small-diameter portion 21 and the reduced-diameter portion 24 are open at the circumferential ends. That is, the large-diameter portion 19 and the small-diameter portion 21 on the distal end side of the large-diameter portion 19 are formed in two steps near the distal end portion of the outer overlapping portion 7b via the oblique wall 20 facing the small-diameter portion 21 side. In the case where the small-diameter portion 21 is open at the distal end side of the large-diameter portion 19 in a cross section perpendicular to the longitudinal direction of the corrugated tube 1, the small-diameter portion 21 opens. Alternatively, in the case where a reduced diameter portion 24 is provided near the distal end portion of the outer overlapping portion 7b and gradually reduces in diameter from the large diameter portion 19 toward the distal end side, the circumferential end of the reduced diameter portion 24 is opened. I do.

  Here, as shown in FIG. 6A, a protruding portion 15 is formed on the inner peripheral portion of the valley of the connection portion of the curved connecting portion 9 where the outer overlapping portion 7b and the curved connecting portion 9 are connected. Is done. As described above, the inner diameter (R1 in the figure) of the protrusion 15 is smaller than the inner diameter (R2 in the figure) of a portion other than the protrusion 15, and the protrusion 15 protrudes toward the center of the curved connection portion 9. .

  On the other hand, since the inner peripheral portion of the inner overlapping portion 7a is disposed inside the outer overlapping portion 7b, the inner overlapping portion 7b has a larger inner diameter than the inner overlapping portion 7b (for example, substantially the same as R2 in the drawing). The inner diameter of 7a (R3 in the figure) is smaller. Therefore, the inner overlapping portion 7a protrudes toward the inner peripheral side with respect to the outer overlapping portion 7b, and a step is formed in the inner peripheral side circumferential direction by the tip of the inner peripheral portion of the inner overlapping portion 7a. The Rukoto.

  However, the protrusion 15 formed near the tip of the inner overlapping portion 7a hides the tip of the inner overlapping portion 7a in the circumferential direction. That is, the tip of the inner overlapping portion 7a is disposed between the inscribed circle (J in the figure) of the innermost diameter portion of the protruding portion 15 and the inner surface of the outer overlapping portion 7b, so that the inner overlapping portion 7a is formed. Can be prevented from projecting toward the inner peripheral side of the corrugated pipe 1 and coming into contact with an electric wire or the like.

  In particular, since the chamfered portion 23 formed by chamfering the protruding portion is formed on the inner surface of the tip of the inner overlapping portion 7a, the pointed portion of the inner overlapping portion 7a is formed on the inner surface of the corrugated tube 1. Projection can be suppressed. For example, even when burrs are formed inside when the above-described cut portion of the corrugated tube is cut, the chamfered portion 23 can prevent the burrs from protruding inside the corrugated tube 1.

  The height of the outer peripheral surface of the ridge 3 of the inner overlapping portion 7a is lower than the inner peripheral surface of the ridge 3 of the outer overlapping portion 7b. For this reason, when the outer overlapping portion 7b and the inner overlapping portion 7a are overlapped, there is a gap between the inner peripheral surface of the crest 3 of the outer overlapping portion 7b and the outer peripheral surface of the crest 3 of the inner overlapping portion 7a. A gap is formed.

  As shown in FIG. 8, when the outer overlapping portion 7b and the inner overlapping portion 7a are overlapped with each other near the connecting portion of the outer overlapping portion, which is near the distal end portion of the inner overlapping portion 7a, A gap is also formed between the inner peripheral surface of the valley 5 of the overlapping portion 7b and the outer peripheral surface of the valley 5 of the inner overlapping portion 7a.

  9A is a sectional view taken along line LL of FIG. 8, FIG. 9B is a sectional view taken along line MM of FIG. 8, and FIG. 9C is a sectional view taken along line NN of FIG. FIG. 9D is a sectional view taken along line OO of FIG. As shown in FIGS. 9A to 9D, in each portion, a gap is provided between the inner peripheral surface of the ridge 3 of the outer overlapping portion 7 b and the outer peripheral surface of the ridge 3 of the inner overlapping portion 7 a. 25 are formed. At this time, the inner peripheral surface of the peak 3 of the outer overlapping portion 7b and the inner overlapping portion 7a at the circumferential end of the small diameter portion 21 of the outer overlapping portion 7b (or the circumferential end of the reduced diameter portion 24). The gap 25 (FIG. 9A) between the outer peripheral surfaces of the peaks 3 is smaller than the gap 25 in the other portions (FIGS. 9B to 9D) of the outer overlapping portion 7b.

  In the height direction, for example, the gap 25 gradually increases from the distal end opening of the outer overlapping portion (FIG. 9A in the LL section) to the distal end of the inner overlapping portion. In the vicinity of the step portion 13 (FIG. 9B of the MM section) and other portions (FIG. 9C of the NN section), substantially the same gap is formed. Thereby, a stable arrangement of the outer overlapping portion and the inner overlapping portion is ensured, and the protrusion of the outer overlapping portion to the outer periphery and the protrusion of the inner overlapping portion to the inner periphery can be suppressed.

  In the longitudinal section of the corrugated pipe 1, the width of the outer peripheral surface of the peak 3 of the inner overlapping portion 7a is smaller than the width of the inner peripheral surface of the peak 3 of the outer overlapping portion 7b. . Therefore, when the inner overlapping portion 7a and the outer overlapping portion 7b are overlapped, a gap 25 is also formed between the outer overlapping portion 7b and the crests 3 of the inner overlapping portion 7a in the width direction.

  In addition, in the vicinity of the distal end portion of the outer overlapping portion 7b (the distal end opening near the small diameter portion 21 and the oblique wall 20) shown in FIG. 9A, the inner peripheral surface of the valley portion 5 of the outer overlapping portion 7b, The outer peripheral surface of the valley portion 5 of the inner overlapping portion 7a contacts. Further, in the vicinity of the distal end opening, as shown in FIG. 9A, a small amount is formed between the outer peripheral surface of the ridge 3 of the inner overlapping portion 7a and the inner peripheral surface of the ridge 3 of the opening of the outer overlapping portion 7b. A gap 25 is formed. At this time, the gap 25 in the vicinity of the opening is smaller than the gap between the outer peripheral surface of the peak 3 of the inner overlapping portion 7a and the inner peripheral surface of the outer overlapping portion 7b in the other overlapping portion.

  When the corrugated pipe 1 is bent in the longitudinal direction with the corrugated pipe 1 facing the outer periphery in a state where the corrugated pipe 1 is closed, the fitting between the tip of the outer superposed section 7b and the inner superposed section 7a is performed. The position moves from the step 13 side of the inner overlapping portion 7a to the tip end side of the inner overlapping portion 7a to balance. For this reason, the gap 25 between the outer overlapped portion 7b and the inner overlapped portion 7a after bending is reduced, but the outer overlapped portion 7b does not protrude outward. A good fitting state of the overlapping portion 7b is maintained, and a stable fitting state is secured.

  As described above, according to the corrugated pipe 1, the opening of the corrugated pipe 1 at the time of bending processing and the shape stability of the overlapped portion of the corrugated pipe 1 are ensured, and the tip of the overlapped portion 7 is formed at the inner circumference or the pipe. Bending workability is good without projecting to the outer periphery of the pipe and damaging the electric wires and peripheral parts.

  As described above, according to the present embodiment, when the corrugated pipe 1 is opened, the electric wires and the like can be accommodated inside the corrugated pipe 1 from the opening 11. No need to send. Thereafter, by closing the corrugated tube 1 as described above, the wires and the like can be reliably protected without the wires and the like being exposed to the outside. In addition, of course, it is also possible to feed and use electric wires and the like with the corrugated pipe 1 closed.

  Further, since the step portion 13 is formed at the connection portion between the curved connection portion 9 and the inner overlapping portion 7a, it is possible to prevent the tip of the outer overlapping portion 7b from projecting to the outer periphery of the corrugated pipe 1 and damaging peripheral components. can do. In addition, since the height of the outer peripheral surface of the peak portion 3 of the inner overlapping portion 7a in the step portion 13 is formed lower than other portions of the inner overlapping portion 7a, the shape of the overlapping portion 7 of the corrugated tube 1 is formed. Becomes stable.

  The outer superposed portion 7b has substantially the same height as the curved connection portion 9 at the outer peripheral surface of the peak portion 3 except for the tip portion. For this reason, no circumferential irregularities or steps are formed on the outer periphery of the corrugated pipe 1, and it is possible to suppress damage to the corrugated pipe 1.

  In particular, by lowering the height of the peak 3 near the tip of the outer overlapping portion 7b toward the tip of the outer overlapping portion 7b, the tip of the outer overlapping portion 7b can be more reliably positioned on the outer periphery of the pipe. It is possible to prevent the peripheral parts from projecting and being damaged.

  In addition, a large-diameter portion 19 and a small-diameter portion 21 are formed in two steps or a reduced-diameter portion 24 that gradually decreases in diameter from the large-diameter portion 19 toward the distal end near the distal end of the outer overlapping portion 7b. The small diameter portion 21 or the reduced diameter portion 24 is provided on the distal end side of the large diameter portion 19 by forming an opening at the distal end of the reduced diameter portion 24, and the outer overlapping portion 7 b is more reliably formed. It is possible to prevent the peripheral parts from being damaged by projecting to the outer periphery of the pipe.

  At this time, a step 13 is provided near the boundary between the inner overlapping portion 7a and the curved connecting portion 9, and when the inner overlapping portion 7a and the outer overlapping portion 7b are overlapped, the tip of the outer overlapping portion 7b is formed. By arranging in the vicinity of the step portion 13, the shape of the overlapping portion 7 of the corrugated pipe 1 can be more reliably stabilized.

  Further, since the protruding portion 15 is formed on the inner peripheral portion of the valley near the connection portion between the curved connecting portion 9 and the outer overlapping portion 7b, the tip of the inner overlapping portion 7a is protected by the protruding portion 15. Is done. For this reason, it can control that the tip of inner side superposition part 7a projects to the pipe inner circumference, and damages the electric wire inside.

  In particular, an R-chamfered or C-chamfered chamfered portion 23 is formed on the inner surface near the tip of the inner overlapping portion 7a. For this reason, for example, when cutting the corrugated base tube, even if cutting burrs are generated in the inner surface direction of the tip of the inner overlapping portion 7a, the pointed portion of the tip of the inner overlapping portion 7a remains inside the corrugated tube 1. It can be prevented from projecting to the periphery and damaging the internal electric wire.

  In addition, a gap 25 is formed between the inner peripheral surface of the crest 3 of the outer overlapped portion 7b and the outer peripheral surface of the crest 3 of the inner overlapped portion 7a. By making the gap of the portion 24 smaller than the gap 25 of the other portion of the outer overlapping portion 7b, intrusion of dust and other undesired objects from near the opening at the tip is suppressed, and the fitting state after the overlapping is performed. And stabilization of the corrugated pipe can be achieved without impairing the flexibility when the corrugated pipe is bent.

  Similarly, by forming a gap 25 in the width direction between the ridges 3 of the outer overlapping portion 7b and the inner overlapping portion 7a, stabilization of fitting after overlapping and flexibility when bending are performed. Performance can be improved.

  As described above, the embodiments of the present invention have been described with reference to the accompanying drawings. However, the technical scope of the present invention is not affected by the above-described embodiments. It is clear that a person skilled in the art can conceive various changes or modifications within the scope of the technical idea described in the claims, and these naturally fall within the technical scope of the present invention. It is understood to belong.

  For example, the corrugated pipe 1 described above does not have a hinge portion, and the cross-sectional shape in the circumferential direction of the curved connection portion 9 is substantially constant. Is also good. It is desirable that the hinge portion is provided substantially at the center of the curved connection portion.

  Further, in order to more reliably maintain the closed state of the corrugated pipe 1, a heat treatment may be performed on the corrugated pipe 1. For example, when the corrugated pipe 1 is made of a thermoplastic resin, the corrugated pipe 1 can be stably maintained in a desired shape by heating the corrugated pipe 1.

  In this case, after the corrugated pipe 1 is heated to a predetermined temperature, the corrugated pipe 1 may be formed into a closed pipe shape, or while the corrugated pipe 1 is heated to a predetermined temperature, the corrugated pipe 1 may be formed into a closed pipe shape. After holding, it may be heated to a predetermined temperature. The processing of the corrugated pipe 1 into the closed pipe shape may be carried out in a batch manner by holding it in a mold, or may be carried out by any method such as roll processing in a heating oven. As the thermoplastic resin, PP (polypropylene) and PA (polyamide) are desirable from the viewpoint of moldability and cost. Further, other thermoplastic resins can be used as appropriate.

1 Corrugated pipe 1a Corrugated pipe 3 Crest section 5 Trough section 7 Overlapping section 7a Inner overlapping section 7b Outside overlapping section 9 ... Curved connection part 11... Opening part 13... Step part 15... Projecting part 17... Cutting part 19... Large diameter part 20. …… Chamfered part 24 …… Diameter part 25 ……… Gap

Claims (11)

A corrugated pipe in which a plurality of peaks and valleys extending in the circumferential direction are alternately formed in the pipe axis direction at predetermined intervals and are repeatedly formed in the pipe axis direction,
The corrugated pipe has an opening that is continuous in the pipe axis direction in a pipe circumferential cross section, and in a cross section perpendicular to the longitudinal direction of the corrugated pipe, the crests and the valleys of the corrugated pipe are provided at both circumferential ends of the corrugated pipe. A portion having overlapping portions where the portions overlap each other, and a curved connection portion connecting the overlapping portions at both ends,
In the overlapping portion, it is possible to arrange the outer overlapping portion on the outer peripheral side of the inner overlapping portion and close the pipe by overlapping the crests and the valleys of the respective overlapping portions. ,
In the curved connection portion and the inner overlapping portion, the peak or the valley is formed continuously,
At the connecting portion between the curved connecting portion and the inner overlapping portion, a step portion is formed in which the outer peripheral side of the connecting portion sharply decreases in diameter, and the outer peripheral portion of the mountain portion of the inner overlapping portion at the step portion Wherein the height of the corrugated pipe is lower than other portions of the inner overlapping portion.   The height of the ridge near the tip of the outer overlapping portion decreases toward the tip of the outer overlapping portion, and when the inner overlapping portion and the outer overlapping portion overlap, the outer The corrugated pipe according to claim 1, wherein a tip of the overlapping portion is disposed near the step portion. The outer overlapping portion, the height of the peak portion is substantially the same as the curved connecting portion except for the tip of the outer overlapping portion,
In the vicinity of the connecting portion between the curved connecting portion and the outer overlapping portion, a projecting portion projecting toward the inner peripheral side of the curved connecting portion is formed,
The corrugated pipe according to claim 1, wherein the projecting portion and the curved connection section are smoothly connected to each other in a cross section perpendicular to a longitudinal direction of the corrugated pipe.   In the vicinity of the distal end portion of the outer overlapping portion, a large-diameter portion and a small-diameter portion formed on the distal end side of the large-diameter portion are formed in two steps, and in a cross section perpendicular to the longitudinal direction of the corrugated pipe, the large-diameter portion has a large diameter. At the distal end of the diameter portion, an oblique wall facing the small diameter portion is provided, and the circumferential end of the small diameter portion is open, or near the distal end of the outer overlapping portion, a large diameter portion is provided. 4. A reduced diameter portion which gradually reduces in diameter from the top toward the front end side is provided, and a circumferential end of the reduced diameter portion is opened. Corrugated pipe.   The height of the outer peripheral surface of the ridge of the inner overlapping portion is formed lower than the inner peripheral surface of the ridge of the outer overlapping portion, and when the overlapping portions are overlapped, A gap is formed between the inner peripheral surface of the ridge of the outer overlapping portion and the outer peripheral surface of the ridge of the inner overlapping portion, and the circumferential end of the small diameter portion of the outer overlapping portion or 5. The corrugated pipe according to claim 4, wherein the gap at a circumferential end of the reduced diameter portion is smaller than the gap at another portion of the outer overlapping portion.   In a cross section of the corrugated pipe in the longitudinal direction of the pipe axis, the width of the outer peripheral surface of the ridge of the inner overlapping portion is smaller than the width of the inner peripheral surface of the ridge of the outer overlapping portion, The corrugate according to claim 4 or 5, wherein a gap is formed between the ridges of the outer overlapped portion and the ridges of the inner overlapped portion when the overlapped portions are overlapped. tube.   At the tip of the valley at the end of the circumferential section of the inner overlapped portion, a curved portion or a straight portion is formed diagonally so that the tip of the valley does not protrude in the inner circumferential direction. The corrugated pipe according to any one of claims 1 to 6, characterized in that:   In the vicinity of the tip of the crest at the end of the circumferential section of the outer overlapped portion, a curved portion or a straight portion is formed diagonally so that the tip of the crest does not protrude in the outer peripheral direction. The corrugated pipe according to any one of claims 1 to 7, characterized in that:   A curve formed in the vicinity of a tip of a circumferential cross section of the inner overlapping portion or the outer overlapping portion of the corrugated pipe so that the tip of the valley or the peak of the tip does not protrude. The corrugated pipe according to claim 7 or 8, wherein the shape or the straight portion is one of an R chamfer and a C chamfer directed in an outer circumferential direction or an inner circumferential direction.   When the corrugated pipe is bent in the longitudinal direction with the overlapping portion facing the outer peripheral side of the bent portion, a fitting position between the tip of the outer overlapping portion and the inner overlapping portion is the inner overlapping portion. The outer overlapping portion and the inner overlapping portion after being bent by moving from the step portion side to the tip portion side of the inner overlapping portion without the outer overlapping portion protruding outward. The corrugated pipe according to any one of claims 1 to 9, wherein a gap of the corrugated pipe is reduced.   The corrugated pipe according to any one of claims 1 to 10, wherein a hinge part is arranged on at least a part of the curved connection part.

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