JP5716429B2 - Corrugated tube and manufacturing method of corrugated tube - Google Patents

Description

  The present invention relates to a corrugated tube for protecting an electric wire and a method for manufacturing the corrugated tube.

  Patent Document 1 discloses a corrugated tube. This is made of a synthetic resin and includes a cylindrical tube body that extends in the axial direction and can be bent elastically. In the tube body, a plurality of ridges and grooves are formed alternately in the axial direction. A rib extending in a straight line along the axial direction is formed in each concave groove while connecting the convex lines. The ribs are arranged in pairs at both ends in the radial direction of the tube body.

  If it is the said structure, the bending operation | movement to the radial direction both ends which become the protrusion direction of a rib will be restrict | limited to the tube main body, and the bending operation to the side orthogonal to the protrusion direction of a rib will be accept | permitted. For this reason, the wiring direction of an electric wire is prescribed | regulated only to predetermined directions, such as a plane direction, and can be used suitably for movable parts, such as a slide door in a motor vehicle.

JP 2007-60754 A

  By the way, in the said conventional corrugated tube, since a rib is provided in the depth range of a ditch | groove, there exists a situation that the protrusion amount of a rib is restrict | limited by the depth of a ditch | groove. Therefore, when the depth of the concave groove is shallow, the protruding amount of the rib is also small, and when a large external force is applied, the tube body may be bent toward both ends in the radial direction different from the original bending direction. is there. On the other hand, if the rib protrudes inward in the radial direction of the tube body, the protruding amount of the rib is not limited by the depth of the groove. However, in this case, since the thickness of the tube body locally increases at the rib forming portion, there is a problem that it is difficult to perform blow molding, which is a general molding method for corrugated tubes.

  The present invention has been completed based on the above circumstances, and an object of the present invention is to provide a corrugated tube capable of restricting the bending direction to a predetermined direction and capable of being blow-molded.

As means for achieving the above object, the invention of claim 1 is a corrugated tube comprising a substantially cylindrical tube body that extends in the axial direction and can be elastically bent, and the tube body includes: A ridge portion is provided that is folded along the axial direction, and the ridge portion protrudes radially inward from a first bent portion along the axial direction on the peripheral wall of the tube body. And a second piece projecting radially inward from a second bent part along the axial direction on the peripheral wall, and a folded part connecting the projecting ends of the first and second pieces. The second bent portion is characterized in that it is formed thinner than the adjacent portion .

The invention of claim 2 is characterized in that, in the invention described in claim 1 , the internal space of the tube main body is partitioned into two chambers via the protrusions.

Invention of Claim 3 is a method of manufacturing the corrugated tube of Claim 1 or 2 , Comprising: A tube main body base material of a form which a pair of halves expand from the said folding | turning part along the said axial direction And then bending both halves through the folded portion in a direction to bring them closer to each other, thereby forming the ridges, and further bending the halves into a cylindrical shape. It is characterized in that it forms a tube body.

<Invention of Claim 1>
Since the tube main body is provided with a protruding portion that is folded along the axial direction, the tube main body is restricted from bending in the protruding direction of the protruding portion, while the tube main body is It is allowed to bend in a direction perpendicular to the protruding direction. Therefore, the bending direction of the corrugated tube is defined in a predetermined direction. In this case, since the protrusion is folded in the axial direction, blow molding can be performed.

Moreover, since the protrusion is configured to protrude inward in the radial direction of the tube main body, interference between the protrusion and the external foreign matter is avoided.

<Invention of Claim 2 >
Since the internal space of the tube main body is partitioned into two chambers via the protrusions, different types of electric wires can be inserted and routed for each room.

<Invention of Claim 3 >
Since the tube body is formed by blow molding, the moldability is excellent. Moreover, the winding state of a tube main body can be reliably hold | maintained by winding a tape around the outer peripheral surface of a tube main body.

It is a perspective view of the one end part of the corrugated tube which concerns on Embodiment 1 of this invention. It is a perspective view of the both ends of the corrugated tube in a bent state. It is a front view of a tube main body base material. It is a front view showing the state which brought the two halves close to each other via the folded portion. It is a front view showing the state before turning both halves into a cylindrical shape. It is a front view showing the state which turned both halves into a cylindrical shape. It is a front view of a corrugated tube.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. The corrugated tube 10 according to the first embodiment is preferably used for movable parts (not shown) such as a slide door part, a slide seat part, a door mirror part, and a tilt type steering part in an automobile, and extends in the axial direction. A cylindrical (circular tubular) tube body 20 that is elastically bendable (bendable and deformable) is provided.

  The tube main body 20 is made of a synthetic resin, and the protruding portions 21 and the concave grooves 22 are alternately formed on the peripheral wall thereof at substantially the same pitch in the axial direction. The projecting portion 21 and the recessed groove 22 are formed in a substantially annular shape that substantially goes around the tube body 20, and the entire peripheral wall of the tube body 20 is configured with substantially the same thickness. In the case of the present embodiment, the protruding amount of the protruding portion 21 and the depth of the concave groove 22 are gradually reduced toward the first and second bent portions 26 and 28 and the slit 23 described later.

  In addition, a slit 23 is formed in the tube main body 20 over the entire length in the axial direction, and the tube main body 20 can be expanded in a direction in which the width of the slit 23 is increased. A plurality of covered electric wires (first and second electric wires 60 and 70 described later) can be inserted into the tube main body 20 through the slits 23 in the open state (see FIG. 7). The slit 23 is always kept closed.

  Now, the tube main body 20 has a ridge 25 formed at a position facing the slit 23 on the opposite side in the radial direction. The protruding portion 25 is configured to be substantially overlapped by folding the peripheral wall of the tube body 20 radially inward along the axial direction. Specifically, the protruding portion 25 includes a first piece portion 27 protruding radially inward from the first bent portion 26 along the axial direction on the peripheral wall of the tube body 20, and a first portion 27 extending along the axial direction on the peripheral wall. 2 It consists of the 2nd piece part 29 which protrudes in the radial inside from the bending part 28, and the folding | turning part 24 which connects both the projecting ends of the 1st, 2nd piece parts 27 and 29. FIG. The first and second bent portions 26 and 28 are arranged on substantially the same line, and the opposing surfaces of the first and second piece portions 27 and 29 are kept in close contact with each other. In the case of the present embodiment, the protrusion 25 is formed over the entire length of the tube body 20 in the axial direction.

  Further, the folded portion 24 is disposed in the vicinity of the slit 23. For this reason, the inside of the tube main body 20 is partitioned into two chambers on both sides in the radial direction with the protrusion 25 as a boundary. One of the divided two chambers becomes a first chamber 31 into which a plurality of first electric wires 60 can be inserted, and the other chamber can insert a plurality of second electric wires 70 different from the first electric wires 60. It becomes the second chamber 32.

Next, a method for manufacturing the corrugated tube 10 will be described.
First, the tube main body base material 33 shown in FIG. 3 is formed by well-known blow molding. The tube body base material 33 includes a folded portion 24 along the axial direction, and a pair of halves 34 that expand from the folded portion 24 to both sides. The first and second pieces 27 and 29 are formed of a pair of straight portions 35 that extend linearly from the folded portion 24 in both halves 34, and the outer peripheral portion of the tube body 20 is formed in both halves 34. It is composed of a pair of semicircular arc portions 36 extending in a semicircular arc shape from the extending end of the straight line portion 35. The extending ends of both straight portions 35 are first and second bent portions 26 and 28, and are formed thin together with the folded portion 24.

  From the above state, when the linear portions 35 are displaced so as to approach each other with the folded portion 24 as a fulcrum, the ridge portions 25 are formed (see FIG. 4). Furthermore, when both the semicircular arc portions 36 are bent and the extension ends are brought into contact with each other and deformed into a circular shape, the tube body 20 is formed (see FIGS. 5 and 6). When the two straight portions 35 are brought close to each other, the folding portion 24 constitutes a cause of bending, and when both the semicircular arc portions 36 are turned, the first and second bent portions 26 and 28 cause the bending. Will be composed.

  Next, the slit 23 of the tube body 20 formed in a cylindrical shape is elastically expanded, and in this state, the first and second electric wires 60 and 70 are inserted into the first and second chambers 31 and 32, respectively. . Thereafter, the holding member 50 such as a tape is wound around and fixed to the outer peripheral surface of the tube main body 20 so that the cylindrical shape (curved shape) of the tube main body 20 is reliably held.

  As shown in FIG. 2, the tube body 20 formed in this way is allowed to bend in a direction perpendicular to the protruding direction of the protruding portion 25, while being parallel to the protruding direction of the protruding portion 25. Bending motion is restricted. Therefore, the tube main body 20 can be displaced along one plane along the direction orthogonal to the protruding direction of the protrusion 25 according to the operation of the movable portion.

  Moreover, in the case of this embodiment, since the protrusion part 25 is made into the form which protrudes to the radial inside of the tube main body 20, interference with the protrusion part 25 and an external foreign material is avoided. Furthermore, the internal space of the tube main body 20 is partitioned into first and second chambers 31 and 32 via the protrusions 25, and different first and second electric wires 60 are provided in the first and second chambers 31 and 32, respectively. , 70 can be inserted and routed. Furthermore, since the tube body 20 is formed by blow molding, the moldability is excellent.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) A well-known clip may be used instead of a tape as a holding member that holds the curved state of the tube body.

  (2) The protruding portion may be formed on a part of the tube body instead of the entire length in the axial direction. In this case, the protrusions may be formed intermittently at intervals in the axial direction of the tube body.

  (3) The protrusion and the slit may be arranged so as to be displaced from each other in the radial direction of the tube main body.

DESCRIPTION OF SYMBOLS 10 ... Corrugated tube 20 ... Tube main body 24 ... Folding part 25 ... Projection part 33 ... Tube main body base material 34 ... Half split

Claims (3)

A corrugated tube having a substantially cylindrical tube body that extends in the axial direction and can be elastically bent,
The tube main body is provided with a protrusion in a form folded along the axial direction ,
The protruding portion protrudes radially inward from the first bent portion along the axial direction in the peripheral wall of the tube body, and radially inward from the second bent portion along the axial direction in the peripheral wall. A second piece projecting toward the top and a folded portion connecting the projecting ends of the first and second pieces, and the first and second bent portions are formed thinner than adjacent portions. Corrugated tube characterized by that. The corrugated tube according to claim 1 , wherein an internal space of the tube main body is partitioned into two chambers via the protrusions . A method for producing a corrugated tube according to claim 1 or 2,
  Blow molding a tube body base material in a form in which a pair of halves expand from the folded portion along the axial direction, and then bend the halves so that they are close to each other via the folded portion The corrugated tube manufacturing method is characterized in that the protrusion is formed, and both the halves are bent into a cylindrical shape to form the tube body.

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