JP2016152715A - Corrugated tube and wire harness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a corrugated tube in which the coated outer surface is not damaged even if a conducting path shakes, and quality degradation of the coated outer surface due to friction or contact does not occur, and to provide a wire harness including this corrugated tube in the constitution.SOLUTION: A corrugated tube 27 has a bellows concave portion 29 and a bellows convex portion 30. A plurality of bellows concave portions 29 and bellows convex portions 30 are formed so as to continue alternately in the tube axis direction. On the inner surface of the corrugated tube 27, inner surface convex portions 31 and inner surface concave portions 32 are formed in accordance with the shape of the bellows concave portions 29 and bellows convex portions 30. Furthermore, on the inner surface of the corrugated tube 27, a soft buffer part 33 is formed integrally. This buffer part 33 is formed only on the top of the inner surface convex portions 31 integrally therewith.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a resin corrugated tube having a bellows concave portion and a bellows convex portion, and a wire harness including the corrugated tube in its configuration.

  A wire harness for electrical connection is routed on a vehicle such as an automobile. As a wire harness, a bundle of thin electric wires is widely known. In recent years, there are also known those made of thick high-voltage electric wires for electric vehicles and hybrid vehicles. Some wire harnesses include a corrugated tube for electric wire protection in this configuration. The corrugated tube has a bellows concave portion and a bellows convex portion, and is formed such that the bellows concave portions and the bellows convex portions are alternately continued in the tube axis direction. As a technique regarding a corrugated tube, it is disclosed by the following patent document 1, for example.

JP 2011-254614 A

  The corrugated tube of Patent Document 1 has a structure for solving the following problems. That is, it has a structure for preventing the corrugated tube from being damaged by the relatively hard wire coating hitting the inner surface of the corrugated tube when vibration during vehicle travel is transmitted to the wire harness. This structure is a double corrugated tube structure consisting of an inner layer and an outer layer. Even if the hardness of the wire coating is higher than the hardness of the corrugated tube (even if it is hard), the corrugated tube on the outer layer side The corrugated tube on the inner layer side interposed between the wire and the electric wire covering functions as a buffer member, and as a result, the corrugated tube on the outer layer side can be prevented from being damaged.

  By the way, this inventor thinks that the corrugated tube useful should be provided also about the case where the hardness of an electric wire coating becomes softer than the hardness of a corrugated tube. In other words, even if the wire swings in such a state that it strikes the inner surface of the corrugated tube, the wire coating will not be damaged, and the quality of the wire coating will deteriorate due to friction and contact. We believe we should provide a corrugated tube with no structure.

  Therefore, the inventor of the present application examined a corrugated tube having a structure as shown in FIGS.

  In FIG. 3, the corrugated tube 1 has a bellows concave portion 2 and a bellows convex portion 3. A plurality of the bellows concave portions 2 and the bellows convex portions 3 are formed so as to continue alternately in the tube axis direction. An inner surface convex portion 4 and an inner surface concave portion 5 are formed on the inner surface of the corrugated tube 1 according to the shape of the bellows concave portion 2 and the bellows convex portion 3. Moreover, the cushion material 8 is disposed and formed on the inner surface of the corrugated tube 1 so as to be interposed between the outer surface 7 of the electric wire 6 (conductive path). The cushion material 8 is made of a material that is relatively soft and has low frictional resistance, and is formed so as to cover the inner surface convex portion 4 and the inner surface concave portion 5 and to completely fill the inner surface concave portion 5.

  According to the corrugated tube 1, since the cushion material 8 having a soft and low frictional resistance is interposed between the outer covering surface 7 of the electric wire 6, even if the electric wire 6 is shaken, damage to the outer covering surface 7 is prevented. be able to. In addition, it is possible to prevent the quality deterioration of the coated outer surface 7 due to friction and contact.

  However, since the inner surface recess 5 is completely filled with the cushion material 8, even if the corrugated tube 1 is bent, it does not bend unless the cushion material 8 expands and contracts. As a result, the corrugated tube 1 shown in FIG. In this case, there is a problem that the original flexibility of the tube is impaired.

  In FIG. 4, the corrugated tube 11 has a bellows concave portion 12 and a bellows convex portion 13. A plurality of the bellows concave portions 12 and the bellows convex portions 13 are formed so as to continue alternately in the tube axis direction. An inner surface convex portion 14 and an inner surface concave portion 15 are formed on the inner surface of the corrugated tube 11 in accordance with the shape of the bellows concave portion 12 and the bellows convex portion 13. Moreover, the tube material 18 is disposed and formed on the inner surface of the corrugated tube 11 so as to be interposed between the outer surface 17 of the electric wire 16 (conductive path). The tube material 18 is integrally formed so as to be fixed to the inner surface convex portion 14 so that the tube material 18 does not hit the inner surface convex portion 14 itself. The tube material 18 is formed to be relatively soft and the tube inner surface is smoothed.

  Since the corrugated tube 11 has a structure in which the tube material 18 having a soft and smooth inner surface is interposed between the outer surface 17 of the electric wire 16 and the outer surface 17 of the electric wire 16 is shaken, the outer surface 17 is not damaged. Can be prevented. In addition, it is possible to prevent the quality deterioration of the coating outer surface 17 due to friction or contact.

  However, since the tube material 18 is structured to be fixed to the inner surface convex portion 14, the tube material 18 does not stretch and bend even if the corrugated tube 11 is bent. As a result, the corrugated tube 11 of FIG. However, there is a problem that the original flexibility of the tube is impaired.

  The present invention has been made in view of the above circumstances, and a corrugated tube that does not damage the outer surface of the coating even if the conductive path swings, and does not cause deterioration of the quality of the outer surface of the coating due to friction or contact, An object of the present invention is to provide a wire harness including the corrugated tube in its configuration.

  The corrugated tube of the present invention according to claim 1 made to solve the above problems is formed in a shape having a bellows concave portion and a bellows convex portion in a circumferential direction when viewed from the outside, and the bellows concave portion and the bellows. Resin corrugate having a shape in which convex portions are formed alternately in the tube axis direction, and an inner surface convex portion and an inner surface concave portion are formed on the inner surface in accordance with the shape of the bellows concave portion and the bellows convex portion. In the tube, the buffer portion having a softness that is softer than the hardness of the outer surface of the covering in one or a plurality of conductive paths accommodated and protected by the corrugated tube is integrally formed only on the top portion of the inner surface convex portion. And

  According to a second aspect of the present invention, in the corrugated tube according to the first aspect, the covering contact surface of the buffer portion is formed in an R shape and smoothly.

  Moreover, the wire harness of this invention of Claim 3 made | formed in order to solve the said subject is the corrugated tube of Claim 1 or 2, and one or several electroconductivity accommodated and protected by this corrugated tube. And a road.

  According to the present invention having the features as described above, since the soft buffer portion is formed only at the top of the inner surface convex portion, the inner surface concave portion remains as it is. That is, since the inner surface concave portion is not filled with the buffer portion, the corrugated tube can be easily bent if it is to be bent, and as a result, the inherent flexibility of the corrugated tube is not impaired. Further, according to the present invention, since the covering contact surface of the buffer portion is formed in an R shape and smooth, the quality deterioration of the covering outer surface due to friction and contact with the covering outer surface of the conductive path does not occur, or It will be significantly reduced.

  According to the first aspect of the present invention, there is an effect that it is possible to provide a corrugated tube that does not damage the outer surface of the coating even if the conductive path is swung.

  According to the second aspect of the present invention, there is an effect that it is possible to provide a corrugated tube that does not cause quality deterioration of the outer surface of the coating due to friction or contact.

  According to the third aspect of the present invention, the corrugated tube is configured such that the outer surface of the coating is not damaged even if the conductive path is swung, and the quality of the outer surface of the coating is not deteriorated due to friction or contact. There exists an effect that the wire harness containing can be provided.

It is a schematic diagram which shows the example of a wiring harness which includes the corrugated tube of this invention in a structure. FIG. 2 is a side view (including a partial cross section) of the wire harness of FIG. 1. It is the figure which added examination with respect to the conventional corrugated tube. It is the figure which added the examination different from FIG. 3 with respect to the conventional corrugated tube.

  The corrugated tube has a bellows concave portion and a bellows convex portion. A plurality of bellows concave portions and bellows convex portions are formed so as to continue alternately in the tube axis direction. An inner surface convex portion and an inner surface concave portion are formed on the inner surface of the corrugated tube in accordance with the shape of the bellows concave portion and the bellows convex portion. A soft buffer portion is integrally formed on the inner surface of the corrugated tube. This buffer portion is integrally formed only at the top of the inner surface convex portion.

  Embodiment 1 will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing an example of a wiring harness including a corrugated tube according to the present invention. 2 is a side view (including a partial cross section) of the wire harness of FIG.

  In the present embodiment, the present invention is applied to a wire harness routed in a hybrid vehicle (which may be an electric vehicle or a general vehicle that runs on an engine).

<About hybrid vehicle 21>
In FIG. 1, reference numeral 21 indicates a hybrid vehicle. The hybrid vehicle 21 is a vehicle that is driven by mixing two powers of an engine and a motor, and electric power from a battery is supplied to the motor via an inverter. Reference numeral 22 indicates a vehicle frame. The upper side of the vehicle frame 22 indicates the vehicle floor top 23, and the lower side of the vehicle frame 22 indicates the vehicle floor bottom 24.

  In the present embodiment, the wire harness 25 of the present invention is routed under the vehicle floor 24 (the routing position is an example, and may be routed, for example, on the vehicle floor 23). The wire harness 25 is routed at a position where vibration is transmitted to itself.

<About the wire harness 25>
1 and 2, the wire harness 25 includes one or a plurality of conductive paths 26, a resin corrugated tube 27 that accommodates and protects the conductive paths 26, and the corrugated tube 27 for fixing the corrugated tube 27 to the vehicle floor 24. The fixing member 28 is configured.

<About the conductive path 26>
The conductive path 26 includes a conductive conductor and an insulating insulator that covers the conductor. The conductor is formed in a circular cross section by copper or copper alloy, or aluminum or aluminum alloy. Or it comprises an insulated wire core made of the conductor and the insulator, a braid (shield member) provided outside the insulated wire core, and a sheath covering the braid. When the former is adopted, the outer surface of the insulator corresponds to the outer surface of the coating described in the claims. Moreover, when the latter is employ | adopted, the outer surface of a sheath shall correspond to the coating | coated outer surface described in the claim.

  Concerning the conductor, a conductor structure in which strands are twisted together or a rod-shaped conductor structure having a rectangular or circular (round) cross section (for example, a conductor structure having a flat single core or a round single core, in this case, The wire itself may be a rod shape). In the conductor as described above, an insulator made of an insulating resin material is extruded on the outer surface.

  The insulator is extruded on the outer peripheral surface of the conductor using a thermoplastic resin material. The insulator is formed as a cover having a circular cross section. The insulator is formed with a predetermined thickness. As the thermoplastic resin, various known types can be used, and are appropriately selected from polymer materials such as polyvinyl chloride resin, polyethylene resin, and polypropylene resin.

  The braid is a metal part for electromagnetic shielding (shield member for electromagnetic wave countermeasures), and is formed by knitting a large number of metal strands into a cylindrical shape.

  The sheath is extruded on the braid using a thermoplastic resin material in the same manner as the insulator. The sheath is formed as a coating. The sheath is formed with a predetermined thickness. As the thermoplastic resin, various known types can be used, and are appropriately selected from polymer materials such as polyvinyl chloride resin, polyethylene resin, and polypropylene resin. It should be noted that a known heat shrinkable tube may be substituted.

<About the corrugated tube 27 of the present invention>
The corrugated tube 27 is formed in a tubular shape having a circular cross section (the cross sectional shape is an example, and may be an oval shape, an elliptical shape, or the like in accordance with the shape or number of the conductive paths 26, for example). . The corrugated tube 27 is formed in the illustrated shape having a bellows concave portion 29 and a bellows convex portion 30 in the circumferential direction when viewed from the outside. Further, the corrugated tube 27 is formed in the illustrated shape such that the bellows concave portions 29 and the bellows convex portions 30 are alternately continued in the tube axis direction (see the center line CL).

  In this embodiment, the corrugated tube 27 is formed so as not to have a slit along the tube axis direction (formed so as not to be split). In other words, it is formed in a shape that can prevent moisture from entering from the outside.

  The bellows recess 29 is formed in a portion that becomes a valley when viewed from the outside. Moreover, the bellows convex part 30 is formed in the part which becomes a mountain when seen from the outside. More specifically, the bellows concave portion 29 is formed in a valley-shaped portion in which a recess having a U-shaped section makes a round around the tube axis. Further, the bellows convex portion 30 is formed in a mountain-shaped portion in which a convex having a cup-shaped cross section goes around the tube axis. The bellows convex portion 30 is not limited to the illustrated shape, and may be formed as an inverted U-shaped convex, for example. The cross-sectional shapes of the bellows concave portion 29 and the bellows convex portion 30 in this embodiment are only examples.

  An inner surface convex portion 31 and an inner surface concave portion 32 are formed on the inner surface of the corrugated tube 27 in accordance with the shapes of the bellows concave portion 29 and the bellows convex portion 30. As can be seen from the figure, the inner surface convex portion 31 is formed in a convex shape as a portion of the corrugated tube 27 viewed from the inside at the position of the bellows concave portion 29. Moreover, the inner surface recessed part 32 is formed in the concave shape as a part which looked at the corrugated tube 27 from the inner side in the position of the bellows convex part 30. FIG. A buffer portion 33 as a characteristic portion of the present invention is formed on the inner surface of the corrugated tube 27 having such a shape.

<About the buffer part 33 as a characteristic part of the present invention>
The buffer portion 33 is integrally formed only on the top portion of the inner surface convex portion 31 on the inner surface of the corrugated tube 27. In addition, the buffer portion 33 is formed in a circumferential direction with a substantially uniform thickness (formed in an annular shape). In the buffer portion 33, when the reference numeral 34 is a covering contact surface that can contact the outer surface of the insulator (covering outer surface) or the sheath outer surface (covering outer surface) of the conductive path 26, the covering contact surface 34 is formed in an R shape and smoothly. Is done. Since the buffer portion 33 is formed only at the top of the inner surface convex portion 31, the inner surface concave portion 32 remains as it is.

  The buffer portion 33 is formed as a portion having a hardness that is softer than the hardness of the outer surface of the conductive path 26. Specific examples of materials that can be used include polyolefin resins, polyamide resins, vinyl chloride resins, silicone resins, fluorine resins, polycarbonate resins, polyimide resins, polyester resins, and polyurethane resins. . A foaming agent may be added to the material. The thickness of the buffer part 33 is preferably 1 μm to 500 μm (the buffer part 33 in the figure is shown in an exaggerated thickness state).

  The buffer portion 33 is formed by extruding and molding or applying the above material (the construction method is not particularly limited).

  The above application will be described in more detail. First, a columnar or cylindrical bar (bar) is prepared, and then the material of the buffer 33 is attached to the outer surface of the bar other than the handle. Subsequently, when the bar is inserted into the corrugated tube 27 and the bar is rotated while the material is in contact with the top of the inner surface convex portion 31, the material is applied only to the top. Thereafter, when the material is hardened, for example, the formation of the buffer portion 33 is completed.

<About the effects of the corrugated tube 27 and the wire harness 25>
As described above with reference to FIGS. 1 and 2, according to the corrugated tube 27 of the present invention, since the soft buffer portion 33 is formed only at the top of the inner surface convex portion 31, the inner surface concave portion 32. Can be left as is. That is, since the inner surface recess 32 is not filled with the buffer portion 33, it can be easily bent if the corrugated tube 27 is bent. Therefore, the corrugated tube 27 can maintain the original flexibility of the tube.

  Further, according to the corrugated tube 27 of the present invention, the covering contact surface 34 of the buffer portion 33 is formed in an R shape and smooth, so that the quality of the covering outer surface due to friction and contact with the covering outer surface of the conductive path 26 is improved. Deterioration is not caused or can be significantly reduced.

  Therefore, a corrugated tube 27 that does not damage the outer surface of the covering even if the conductive path 26 swings, and does not cause deterioration of the quality of the outer surface of the covering due to friction or contact, and a wire harness that includes the corrugated tube 27 in its configuration. 25 can be provided.

  It goes without saying that the present invention can be variously modified without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 21 ... Hybrid vehicle 22 ... Vehicle frame 23 ... Vehicle floor 24 ... Vehicle floor 25 ... Wire harness 26 ... Conductive path 27 ... Corrugated tube 28 ... Fixing member 29 ... Bellows recessed part 30 ... Bellows convex part 31 ... Internal surface convex part 32 ... Internal surface concave part 33 ... Buffer part 34 ... Coating contact surface

Claims (3)

It is formed in a shape having a bellows concave portion and a bellows convex portion in the circumferential direction when viewed from the outside, and the bellows concave portions and the bellows convex portions are formed in a shape that alternately continues in the tube axis direction, and In the corrugated tube made of resin in a shape in which the inner surface convex portion and the inner surface concave portion are formed according to the shape of the bellows concave portion and the bellows convex portion,
A corrugated portion having a softness that is softer than the hardness of the outer surface of the covering in one or a plurality of conductive paths accommodated and protected by the corrugated tube is integrally formed only at the top of the inner surface convex portion. tube. The corrugated tube according to claim 1,
The corrugated tube, wherein the covering contact surface of the buffer portion is formed in an R shape and smooth. A wire harness comprising the corrugated tube according to claim 1 or 2 and one or a plurality of conductive paths accommodated and protected by the corrugated tube.

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