JPH08149659A - Grommet for wire harness - Google Patents

Abstract

PURPOSE: To improve waterproof property of the insert-coupling section of a conduit tube section and to make the mounting work of the connecting section on an electric wire bundle simpler and more efficient in a grommet for a wire harness constituted by connecting the conduit tube section for passing the electric wire bundle of a wire harness to a through hole fitting section which is fitted and fixed to a through hole on a car body side and into and with which the conduit tube section is inserted and couple. CONSTITUTION: An insert-coupling section 10 is composed of a coupling outer tube 5 which is the end section of a conduit tube section 3A and a coupling inner tube 6 which is the end section of another conduit tube section 3B and the inner tube 6 has an inside diameter D1 which is nearly equal to the diameter of the thickest electric wire bundle 4 to be inserted into the tube 6, a wall thickness T1 which is almost double the wall thickness T2 of the conduit tube section 3B, and a pair of slots 7 for opening the pipe 6 formed in the length direction from the front end of the tube 6. When the bundle 4 to be inserted is thicker, the bundle 4 is passed by opening the slots 7 and the insert-coupling section 10 is waterproofed by winding a tape 8 around the section 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, when a wire harness is arranged to penetrate a wall plate of a vehicle body or equipment, is mounted on the wire harness and attached to a through hole, and the wire harness is arranged in a penetrating position. The present invention relates to a grommet for a wire harness which is used to hold the wire and to waterproof the through portion.

[0002]

2. Description of the Related Art A wire harness grommet (see FIG. 2) is a through hole for inserting a wire bundle 4 of a wire harness into a through hole of a wall plate of a vehicle body or the like through which the wire harness is to be penetrated and fixed in a waterproof manner. Basic of elastic body made of rubber in which the hole attachment part 2 is formed as a main part, and the electric wire bundle 4 that passes through the through hole attachment part 2 is continuously inserted to protect the electric wire tube part 3 It has a structure.

Then, as shown in the drawing, when the electric wire tube portion 3 has the through hole attachment portions 2A and 2B at both ends thereof and the electric wire tube portion 3 becomes long, or the center line of the through hole attachment portion 2 is formed. On the other hand, in the case of the L-shaped bending arrangement in which the conduit portion 3 is bent orthogonally, it becomes difficult to thread the wire bundle 4 into the conduit portion 3, so that the middle portion of the conduit portion 3 is divided into 3A. 3B is a joint conduit section, and after inserting the bundle of wires 4 into the respective conduit sections 3A and 3B, the ends of the conduit sections 3A and 3B are inserted into and connected to each other, and the tape winding 8 is performed from above. And give
A connection-type conduit tube structure having a waterproof connection portion is used.

In this connection type conduit tube structure, only the tape winding 8 applied to the outer periphery of the connection part is
Since waterproofness cannot be ensured, a method of fitting a slightly long protective tube 12 to the electric wire bundle 4 that hits the connecting portion and waterproofing the connecting portion by double sealing with the protective tube 12 and the tape winding 8 is adopted. Has been.

[0005]

The electric wire tube portion 3 having the above-mentioned connection type electric wire tube portion structure has a structure in which the electric wire bundle 4 and the electric wire bundle 4 inserted loosely are inserted for the purpose of easily inserting the electric wire bundle 4 and protecting it in a waterproof state. There is a gap 11 between the inner circumference of the tube portion 3 and the wire tube portions 3 of the same size, through which the wire bundles 4 having different bundle diameters within the permissible insertion range are passed. The void volume can be quite large. Therefore (see FIG. 2C), the tape winding 8 is performed on the elastic wire conduit portion 3 having a large clearance 11 inside the tube.
When subjected to, wrinkles 13 may be formed on the peripheral wall of the electric wire tube portion 3 due to the winding pressure of the tape winding 8, and water may be infiltrated from the wrinkles 13 into the pipe.

From the above, the conventional grommet for the wire harness having the connection type electric wire tube portion structure is not waterproof and
Since it is necessary to carefully perform the tape winding 8 while paying attention to the occurrence of wrinkles 13, the work is difficult to perform, and in addition, an extra work step and a member (protection tube 12) for previously mounting the protection tube 12 are required. However, the workability of mounting the grommet for the wire harness on the wire harness is poor, and there is a drawback that the cost is increased. Furthermore, since the quality of the waterproofness depends on a sensory judgment visually confirming the presence or absence of the wrinkles 13, the waterproofness due to the presence of the wrinkles 13 is overlooked and attached to the actual vehicle, and the waterproofness is ensured during use. There is a problem in quality assurance that causes trouble.

The present invention provides a grommet for a wire harness that solves the above-mentioned drawbacks of the prior art.

[0006]

The grommet for wire harness of the present invention which solves the above technical problem is "through hole removal for inserting and fixing wire bundles of wire harness into through holes on the vehicle body / device side. The connecting part and the through-hole mounting part are connected to each other and consist of an electric wire tube part for inserting the electric wire bundle. The middle part of the electric wire tube part is divided into a separate body, and the divided end is inserted and connected. In the wire harness grommet, the inner diameter of the connecting inner tube that is the inner tube of the insertion connection of the connecting portion is smaller than the inner diameter of the electric wire tube portion following the connecting inner tube, and the insertion maximum diameter wire bundle diameter is set. It has a substantially uniform inner diameter, and further has a structure in which at least a pair of opening slits extending from the distal end in the pipe length direction are provided in the connecting inner pipe. "

That is, in the wire harness grommet of the present invention, the inner diameter of the connecting inner tube portion is made small so that the amount of play with the inserted wire bundle is made as small as possible, and the tape winding at the connecting portion is performed. The thick wire bundle that prevents wrinkles from being generated and that is difficult to pass through the connecting inner tube is opened in a crocodile shape by opening the above-mentioned opening slit, which makes it extremely easy to pass the wire bundle. I am trying.

[0009]

In the wire harness grommet of the present invention having the above-described structure, the amount of play between the wire bundle and the inner circumference of the pipe at the connecting portion of the electric wire tube portion is reduced, and the inner diameter is reduced to reduce the amount of play. Since the wall thickness of the connected inner pipe is substantially thicker than that of the conduit portion other than the connected inner pipe to improve the rigidity, the original shape is formed against the winding resistance of the tape winding applied to the connected portion. By being held, the risk of wrinkling of the tubular body due to the winding resistance of the tape winding is extremely reduced, and the waterproof property of the portion is improved.

With the improvement of the waterproof property, the conventional protection tube becomes unnecessary, and the workability of attaching the wire harness grommet to the wire harness is simplified and the efficiency is improved, and even when the thick wire bundle is passed through. By utilizing the above-mentioned opening slit, there is no possibility of lowering the insertion workability.

[0011]

Embodiments will be described in detail below based on embodiments. That is, referring to FIG. 1 showing a wire harness grommet according to an embodiment of the present invention, a through hole (not shown) in a wall plate of a vehicle body.
Following the through hole attachment portion 2A that is waterproofly fitted to the wire harness, one wire harness grommet 1A having the electric wire tube portion 3A through which the wire bundle 4 of the wire harness is inserted, and the other through hole is also fitted. It consists of the other wire harness grommet 1B in which the electric wire tube portion 3B through which the electric wire bundle 4 is inserted is continuously provided following the through hole attachment portion 2B, and the end portions of the electric wire tube portions 3A and 3B are inserted and connected to form a single piece. Of the electric wire tube portion 3 and the electric wire bundle 4 is inserted and protected in the electric wire tube portion 3 that is in communication with the electric wire tube portion 3, the insertion connecting portion 10 of the electric wire tube portions 3A and 3B is configured as follows. ing. The wire harness grommet 1A of this embodiment has an L-shaped arrangement in which the conduit portion 3A is substantially orthogonal to the through hole attachment portion 2A.

That is, the insertion connecting portion 10 has such a shape that the tip end portion of the electric wire tube portion 3A to be interconnected becomes the connecting outer pipe 5 and the other end portion of the electric wire pipe portion 3B becomes the connecting inner pipe 6. By lightly inserting the inner connecting pipe 6 into the outer connecting pipe 5, both can be lightly and closely contacted and connected.

The connecting inner tube 6 has an inner diameter D1 that is approximately equal to the diameter of the wire bundle 4 having the largest diameter to be inserted, and has the same outer diameter D as the electric wire tube portion 3B extending integrally rearward.
2, and the pipe wall thickness T1 of the connecting inner pipe 6 is approximately twice the pipe wall thickness T2 of the conduit portion 3B.

Further, the connecting inner pipe 6 is provided with a pair of opening slots 7 extending in the pipe length direction from the tip and positioned on the same diameter. The opening slot 7 is formed by opening the tip portion with a fingertip. The tube wall divided into upper and lower parts from the bottom as a starting point is easily elastically opened like a crocodile, and even a thick wire bundle 4 has a shape that can be easily inserted. Reference numeral 9 in the drawing denotes a stopper for restricting the insertion amount when the connection inner pipe 6 is inserted and connected to the connection outer pipe 5.

In the above wire harness grommet, the wire tube portions 3A and 3B are separated from each other, and the wire harness 4 is attached to the wire harness through the bare wire bundle 4 without a waterproof member such as a protective tube, and then connected. The inner pipe 6 is inserted and connected to the outer pipe 5 to unify the two electric wire pipe portions 3A and 3B, and a tape winding 8 for waterproofing is provided on the insertion connecting portion 10 to penetrate the vehicle body. It is attached and fixed to the hole.

In the wire harness grommet of the embodiment shown in FIG. 1 described above, the connecting inner pipe 6 of the insert connecting portion 10 of the divided electric wire pipe portion 3 has the inner pipe D1 having a smaller requirement and a thicker pipe wall thickness T1. Therefore, when the wire bundle 4 having the maximum diameter is passed, there is no play between the connection inner tube 6 and the wire bundle 4, and the outer circumference of the connection outer tube 5 closely fitted to the connection inner tube 6 Even if the tape winding 8 is tightly wound, the connecting inner tube 6 is elastically reduced in diameter and does not cause wrinkles, fits the wire bundle 4, and the waterproof property of the portion can be extremely excellently secured. The workability of inserting the wire bundle 4 into the connecting inner pipe 6 can be easily performed by utilizing the opening slit 7.

Further, when the wire bundle 4 having the smallest diameter is inserted (see (D) of FIG. 1), although there is some play 11 between the wire bundle 4 and the connecting inner pipe 6, the play is caused. The absolute amount of the gap 11 is extremely smaller than that of the conventional structure, and since the connecting inner pipe 6 has a thick pipe wall thickness T1, the rigidity against the external force from the outer circumference toward the center is strong, and the tape winding 8
It is extremely unlikely that the diameter is easily reduced or the outer peripheral wrinkles are generated due to the winding force, and the waterproofness of the insertion connecting portion 10 can be excellently secured.

Since the risk of wrinkling is reduced, it is not necessary to pay too much attention to the winding of the tape 8. Moreover, the improvement of the waterproof property makes it unnecessary to attach the conventional protective tube 12 as well. As a result, the work of attaching the grommet to the wire harness is further simplified and the cost can be reduced.

The wire harness grommet of the present invention is not limited to the above-mentioned embodiment, and the outer diameter of the connecting inner pipe 6 is different from that of the electric wire pipe portion 3B, and the opening slots 7 are arranged on three circumferences. There are changes such as setting.

[0020]

As described above, in the wire harness grommet of the present invention, when the middles of the electric wire tube portions connected to the through hole attachment portion are mutually inserted and connected, the insertion connecting portion is waterproof. In addition to improving the quality assurance of the wire harness grommet with good stability, the workability of attaching the wire harness to the wire harness is improved and the cost is reduced.

[Brief description of drawings]

1A and 1B show a grommet for a wire harness according to an embodiment of the present invention, in which FIG. 1A is a front view before connecting a conduit portion, FIG. 1B is an enlarged perspective view of an inserting connector portion, and FIG. Front view of the state, (D) is an enlarged cross-sectional view of the state of use

FIG. 2 shows a conventional wire harness grommet,
(A) is a front view before connecting the conduit section, (B) is a front view showing a connecting procedure and a connecting state of the connecting tube section, and (C) is a cross-sectional view in a used state.

[Explanation of symbols]

 1A ・ 1B Grommet for wire harness 2A ・ 2B Through hole attachment part 3A ・ 3B Conduit tube part 4 Wire bundle 5 Connection outer pipe 6 Connection inner pipe 7 Opening slot 8 Tape winding 10 Insertion connection part 11 Free play 12 Protective tube 13 wrinkle

Claims (2)

[Claims] 1. A through-hole attaching portion for inserting and fixing a wire bundle of a wire harness into a through-hole on a vehicle body / device side, and a wire bundle connected to the through-hole attaching portion to connect the electric wire bundle. A wire harness grommet in which a wire tube portion to be inserted is formed, the middle of the wire tube portion is divided to form a separate body, and the divided end is inserted and connected. The inner diameter of the pipe is made smaller than the inner diameter of the electric wire tube portion following the connecting inner pipe so that the inner diameter of the electric wire tube is approximately equal to the maximum diameter of the wire bundle, and the connecting inner pipe extends from the tip in the pipe length direction. A grommet for a wire harness characterized by a structure having at least a pair of opening slits. 2. The grommet for a wire harness according to claim 1, wherein a pipe wall thickness of the connection inner pipe portion is approximately twice a pipe wall thickness of an electric wire pipe portion following the connection inner pipe.