Electric wire protection material and wire harness

Abstract

To provide an electric wire protection material with high stretchability, capable of avoiding interference with an object that exists on a wiring route of a wire harness, and a wire harness including the electric wire protection material.SOLUTION: A wire harness 1 is wired in an automobile, and includes an electric wire 3, a connector 2 connected to one end of the electric wire 3, a rubber boot 5 and a protection tube 4. A bellows part 53 is formed in the rubber boot 5. The bellows part 53 has such a shape that some portions facing a metal edge 8 of the automobile are crushed, in order to avoid interference with the metal edge 8. In addition, a small bellows part 54 having a pitch narrower than that of the bellows part 53 is formed in a flat portion caused by the crushed shape. The wire harness 1 is bent on a side opposite to the metal edge 8 in the bellows part 53. Since the bellows part 53 has the small bellows part 54, the bellows part has high stretchability and can be bent without applying tension on a tape 7 and a tie band 6.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wire protection material that is applied to the exterior of wires of a wiring harness. [Background technology]

[0002] Rubber boots (see Patent Document 1) and grommets are known as wire protection materials for automotive wire harnesses. In a vehicle wiring structure for a wire harness equipped with these rubber boots or grommets, a metal edge of the vehicle may be present in the wiring path. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-340292 Summary of the Invention [Problem to be solved by the invention]

[0004] 4 is a diagram showing a vehicle wiring structure 510 of a wire harness 501 of a reference example devised by the present inventor to avoid interference with a metal edge 8 of a vehicle present in the wiring path. In the wire harness 501, a connector 2 is connected to one end of the electric wires 3, and a rubber boot 505 is attached to the connection portion between the electric wires 3 and the connector 2. In addition, a protective tube 4 is attached to the other end side of the electric wires 3 from the connection portion.

[0005] One end of rubber boot 505 is fixed to connector 2 by a tie band 6. The other end of rubber boot 505 is fixed to protective tube 4 by tape 7. A bellows portion 553 is formed in the middle of rubber boot 505.

[0006] In the vehicle wiring structure 510 of this wire harness 501, a part of the bellows portion 553 is crushed to prevent it from bulging outward in the radial direction in order to avoid interference with the metal edge 8 present in the wiring path. The crushing forms a flat surface 554.

[0007] In the vehicle wiring structure 510, when the bellows portion 553 is bent in the vehicle layout, the amount of stretch is insufficient because the bellows portion 553 includes the flat surface 554, and the rubber boot 505 may come off the fastener (tape 7, tie band 6, etc.). That is, the bellows portion 553 is partially crushed to form the flat surface 554, and therefore the flexibility, which is the original purpose of the bellows, is reduced.

[0008] Although it is possible to prevent rubber boot 505 from coming off by designing bellows portion 553 to be longer, this increases the amount of rubber used and raises the cost of parts.

[0009] Therefore, an object of the present invention is to provide a wire protection material with good elasticity that can avoid interference with objects present in the routing path of the wire harness, and a wire harness equipped with the wire protection material. [Means for solving the problem]

[0010] The wire protection material of the present invention is applied to the exterior of the wires of a wire harness, and is characterized in that it has a bellows portion formed with alternating large diameter portions and small diameter portions, and in that small bellows portions are formed in a circumferential portion of some of the large diameter portions, with the small bellows portions having a narrower pitch than the bellows portions, and the small bellows portions are located radially inward of the large diameter portions.

[0011] The wire harness of the present invention comprises an electric wire, a connector connected to an end of the electric wire, and a rubber boot fitted around the connection portion between the connector and the electric wire, and is characterized in that the rubber boot comprises the above-mentioned wire protection material. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a wire protecting material with good elasticity that can avoid interference with objects present in the routing path of the wire harness, and a wire harness including the wire protecting material. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a perspective view showing a rubber boot as a wire protecting member according to an embodiment of the present invention. [Figure 2] FIG. 2 is a plan view of the rubber boot of FIG. 1. [Figure 3] 2 is a diagram showing a vehicle wiring structure of a wire harness provided with the rubber boot of FIG. 1. FIG. [Figure 4] 1 is a diagram showing a vehicle wiring structure of a wire harness according to a reference example; DETAILED DESCRIPTION OF THE INVENTION

[0014] A "wire protective material" and a "wire harness" according to one embodiment of the present invention will be described with reference to FIGS.

[0015] 1 and 2 are diagrams showing a rubber boot 5 as a “wire protection material.” FIG. 3 is a diagram showing a vehicle wiring structure 10 of a wire harness 1 provided with the rubber boot 5.

[0016] The wire harness 1 is arranged in an automobile and includes electric wires 3, a connector 2 connected to one end of the electric wires 3, a rubber boot 5, and a protective tube 4. The rubber boot 5 is fitted over the connection portion between the connector 2 and the electric wires 3. The protective tube 4 is fitted over the other end side of the electric wires 3 relative to the connection portion.

[0017] A metal edge 8 of the vehicle exists in the wiring path of the vehicle wiring structure 10 of this wire harness 1. Moreover, due to the mounting layout of the vehicle, the wire harness 1 is bent in the vicinity of the metal edge 8 to the opposite side to the metal edge 8.

[0018] The rubber boot 5 is made of rubber and is formed into a cylindrical shape overall. One end 51 of the rubber boot 5 is fixed to the connector 2 by a tie band (sometimes called a cable tie) 6. An annular groove 55 for winding the tie band 6 is formed in the one end 51 of the rubber boot 5. The other end 52 of the rubber boot 5 is placed over the end of the protective tube 4 and is fixed to the protective tube 4 by wrapping tape 7 around it.

[0019] A bellows portion 53 is formed in the middle portion of the rubber boot 5. The bellows portion 53 has a plurality of alternating large diameter portions 53a and small diameter portions 53b. The small diameter portions 53b have smaller inner and outer diameters than the large diameter portions 53a. In this example, the bellows portion 53 has three large diameter portions 53a and two small diameter portions 53b.

[0020] The bellows portion 53 is disposed in the vicinity of the metal edge 8. In order to avoid interference with the metal edge 8, the part of the bellows portion 53 that faces the metal edge 8 has a flattened shape so as to suppress bulging outward in the radial direction. In this example, the central large diameter portion 53a of the three large diameter portions 53a has a flattened shape on the side of the metal edge 8, i.e., a part in the circumferential direction.

[0021] Then, small bellows portion 54 is formed in the flat portion resulting from the crushed shape, with a pitch narrower than bellows portion 53. Small bellows portion 54 has multiple alternating peaks 54a formed convexly toward metal edge 8 and multiple valleys 54b formed concavely on the opposite side. Peaks 54a and valleys 54b are alternately arranged in the central axial direction of bellows portion 53. The pitch between peaks 54a and valleys 54b is narrower than the pitch between large diameter portion 53a and small diameter portion 53b. Small bellows portion 54 has a corrugated cross-sectional shape. Furthermore, when rubber boot 5 is in its natural state (unbent state) as shown in FIGS. 1 and 2 , small bellows portion 54 is located radially inward of large diameter portion 53a, which has a portion that is not crushed in the circumferential direction.

[0022] The rubber boot 5 is obtained by filling a mold with rubber material and removing it from the mold after the rubber material has hardened. That is, in the present invention, "a part of the large diameter portion in the circumferential direction is crushed" does not mean that the rubber boot is crushed by some processing after molding, but rather that the part of the large diameter portion in the circumferential direction is molded into a crushed shape in advance during molding.

[0023] Because the small bellows portion 54 is formed, the side length from one end of the rubber boot 5 to the other end thereof, passing through the small bellows portion 54 (dashed line A in FIG. 2), is the same as the side length from one end of the rubber boot 5 to the other end thereof without passing through the small bellows portion 54 (dashed line B in FIG. 2). These side lengths are not linear distances from one end to the other end of the rubber boot 5, but are distances along the bellows shape. In other words, the side length from one end of the bellows portion 53 to the other end thereof, passing through the small bellows portion 54 (the length from A1 to A2 on the dashed line A in FIG. 2), is the same as the side length from one end of the bellows portion 53 to the other end thereof without passing through the small bellows portion 54 (the length from B1 to B2 on the dashed line B in FIG. 2).

[0024] In addition, in the vehicle wiring structure 10 of this example, the wire harness 1 is bent at the bellows portion 53 toward the side opposite to the metal edge 8. As described above, in the wire harness 501 of the reference example shown in FIG. 4, the bellows portion 553 includes a flat surface 554, and therefore the amount of stretch when bending is insufficient, and the rubber boot 505 may come off from the fastener (the tape 7, the tie band 6, etc.). In contrast, in the wire harness 1 of this example shown in FIG. 3, the bellows portion 53 has a small bellows portion 54, and therefore has high stretchability. Therefore, the bellows portion 53 can be bent without applying tension to the fastener (the tape 7, the tie band 6, etc.), and the rubber boot 505 can be prevented from coming off from the fastener.

[0025] Moreover, the above-described rubber boot 5 stretches well even when the bellows portion 53 is bent in any direction, thereby increasing the degree of freedom in handling the wire harness 1. Furthermore, the above-described rubber boot 5 requires only a minimum amount of rubber, thereby enabling costs to be kept low.

[0026] Although the above-described embodiment has been described using a rubber boot as an example of a wire protective material, the present invention can also be applied to a grommet as a wire protective material. That is, a portion of the bellows portion of the grommet may be formed into a flat or other flattened shape, and a small bellows portion having a narrower pitch than the bellows portion may be formed in this flattened portion.

[0027] The above-described embodiment merely shows a typical form of the present invention, and the present invention is not limited to this embodiment. In other words, the present invention can be implemented with various modifications within the scope of the gist of the present invention. As long as such modifications still include the configuration of the present invention, they are of course included in the scope of the present invention. [Explanation of symbols]

[0028] 1 Wire harness 2 connectors 3 electric wire 5 Rubber boots (wire protection material) 53 Bellows 54 Small bellows section

Claims

1. It is attached to the wires of the wire harness, A bellows portion having alternating large diameter portions and small diameter portions is formed, A small bellows portion having a narrower pitch than the bellows portion is formed in a part of the circumferential direction of a part of the large diameter portion, The small bellows portion is located radially inward of the large diameter portion. A wire protection material characterized by:

2. A side length from one end of the bellows portion through the small bellows portion to the other end of the bellows portion is the same as a side length from one end of the bellows portion to the other end of the bellows portion without passing through the small bellows portion. The wire protective material according to claim 1 .

3. The connector includes an electric wire, a connector connected to an end of the electric wire, and a rubber boot fitted around a connection portion between the connector and the electric wire, The rubber boot is provided with the wire protection material according to claim 1 or 2. A wire harness characterized by:

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