JP2008218110A - Grommet for wire harness - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce insertion force without reducing the fixation force of a grommet. <P>SOLUTION: The grommet comprises: a small-diameter cylinder section 13 for inserting a group of electric wires in a wire harness W/H; a grommet body 11 having a diameter expansion section 14 continuous to the tip of the small-diameter cylinder section 13; and a resin inner 12 assembled to the inside of the diameter expansion section 14 in the grommet body 11. A locking piece 20 locked to the periphery of a through hole H in a body panel P with a gap in a circumferential direction is provided at a projecting circumferential wall section 17 in the resin inner 12. Each locking piece 20 has a locking nib 22 by cutting out the tip of a folding section 21 bent from the tip of the circumferential wall section 17 in steps. An outer surface 17a in the folding section 17 in slide contact with the inner-periphery surface of the through hole H projects so that a center in a width direction becomes the top. A linear slide contact section 23 where the top is continuous from the bent position to the tip side is formed. Further, the top section 24 spreads over the entire length in a width direction at the tip side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a grommet for a wire harness, and more specifically, in a grommet that is assembled to a wire harness routed in an automobile and attached to a through hole of a vehicle body panel, a resin inner is fitted inside the grommet body, and the inner It is related with what is latched and attached to the through-hole of a vehicle body panel with the latching claw protrudingly provided on the outer surface of the vehicle.

  A grommet attached to a wire harness routed in an automobile is attached to a through-hole provided in a vehicle body panel that separates the passenger compartment from the exterior to prevent water from entering the room. A grommet 1 shown in FIG. 10 is an example of this type of grommet, and has a through hole (not shown) at the tip of a small-diameter wire insertion portion 3 that is inserted in close contact with the outer periphery of a wire harness (not shown). 3) a grommet main body 2 provided with a diameter-enlarged portion 4 that closely contacts the distal end surface thereof, and a resin inner 6 that is fitted into the diameter-enlarged portion 4. On the outer peripheral surface of the resin inner 6, a locking piece 7 whose front end is folded outward is projected. (See JP-A-9-129065)

  The grommet 1 inserts the distal end portion of the resin inner 6 into a through hole, and engages the locking piece 7 with the indoor peripheral edge of the through hole, whereby the sealing portion 5 at the distal end of the enlarged diameter portion 4 is obtained. Is attached with a single touch in a sealed state that is crimped to the outer peripheral edge of the through hole.

  However, in the conventional grommet 1 having the above-described configuration, as shown in FIG. 11, the outer surface 7a of the locking piece 7 is a flat surface in the width direction (circumferential direction), so that the resin inner 6 is inserted into the through hole. The outer surface 7a of the locking piece 7 and the inner peripheral surface of the through hole are in surface contact with each other. For this reason, a strong insertion force is required, and there is a problem in that the mounting workability to the vehicle body panel is poor.

  Regarding the above-mentioned problem, as means for reducing the insertion force, there are methods such as 1) reducing the latching margin L1 of the locking piece 7 and 2) reducing the width L2 of the locking piece 7, all of which are locking pieces. 7 also has a problem in that the fixing force to the through hole is reduced and the grommet is easily detached.

Japanese Patent Laid-Open No. 9-129065

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a grommet for a wire harness that can improve the mounting workability by reducing the insertion force without reducing the fixing force of the grommet to the vehicle body panel.

In order to solve the above-mentioned problem, as a first invention, a grommet for inserting and fixing an electric wire group of a wire harness routed in a vehicle to a through hole of a vehicle body panel,
A small-diameter cylindrical portion that is molded with rubber or elastomer, and the wire group is inserted, and a grommet body that includes an enlarged-diameter portion continuously at the tip of the small-diameter cylindrical portion;
It is assembled in the inside of the enlarged diameter part of the grommet main body, and consists of a resin inner made of a resin molded product partly protruding from the tip opening of the enlarged diameter part,
On the peripheral wall from which the inner resin protrudes, there is provided a locking piece for locking to the peripheral edge of the through hole of the vehicle body panel with an interval in the circumferential direction.
Each locking piece is provided with a locking claw by notching the tip of the folded portion bent from the tip of the peripheral wall in a stepped manner, and the outer surface of the folded portion that is in sliding contact with the inner peripheral surface of the through hole is: It protrudes so that the center in the width direction becomes the summit, and a linear sliding contact portion is formed in which the summit continues from the bent position to the tip side. A grommet for a wire harness is provided.

  In the grommet configured as described above, a linear sliding contact portion that is continuous in the insertion direction protrudes from the outer surface of the folded portion of the resin inner, so when inserting the resin inner into the through hole, Are in line contact with only the top of the linear sliding contact portion. Therefore, compared with the conventional grommet in which the outer surface of the folded portion and the inner peripheral surface of the through hole are in surface contact, the contact area at the time of insertion is reduced, so that the insertion load can be reduced. Accordingly, the resin inner can be easily inserted into the through hole with a weak insertion force, and the grommet mounting workability can be improved.

Moreover, since the width | variety and folding allowance of folding | turning part itself can maintain the conventional dimension, only insertion force can be reduced, without reducing the fixing force of a locking piece.
By extending the summit of the linear sliding contact portion to the entire length in the width direction on the tip side, there is an advantage that the locking force with the vehicle body is not reduced.

Further, as a second invention, a grommet for inserting and fixing a wire group of a wire harness routed in a vehicle and mounting and fixing it in a through hole of a vehicle body panel,
A small-diameter cylindrical portion that is molded with rubber or elastomer, and the wire group is inserted, and a grommet body that includes an enlarged-diameter portion continuously at the tip of the small-diameter cylindrical portion;
It is assembled in the inside of the enlarged diameter part of the grommet main body, and consists of a resin inner made of a resin molded product partly protruding from the tip opening of the enlarged diameter part,
The peripheral wall from which the resin inner protrudes is provided with a locking piece forming recess that is locked to the peripheral edge of the through hole of the vehicle body panel with an interval in the circumferential direction.
Also provided is a grommet for a wire harness, wherein each of the locking piece forming recesses is provided with a first divided locking piece and a second divided locking piece which are narrow in the circumferential direction and spaced apart. ing.

Thus, by providing the locking piece divided into two narrow locking pieces, the contact area between the outer surface of the locking piece and the inner peripheral surface of the through hole can be reduced, so that weak insertion The resin inner can be easily inserted into the through hole by force.
In addition, by providing the narrow first divided locking piece and the second divided locking piece at intervals in the circumferential direction, it is possible to ensure a wide range of fixing force by one set of locking pieces. , The holding power of the grommet can be increased.

Each of the first divided locking piece and the second divided locking piece is provided with a locking claw by cutting out the front end of the folded portion bent from the front end of the peripheral wall in a step shape, and the front end side of the folded portion is It is preferable that it is connected with a connecting piece having flexibility.
By making the shape of the locking claw the stepped shape, the locking claw can be brought into contact with and locked to both the inner peripheral surface of the through hole and the peripheral edge on the indoor side. In addition, it is possible to prevent backlash of the resin inner in the through hole.
Further, by connecting and integrating the first divided locking piece and the second divided locking piece at the front end side of the folded portion, half-fitting of the locking piece can be prevented, and the accuracy of the grommet mounting work can be prevented. Can be secured.

  The resin inner in the grommet body is provided with an annular protrusion from the outer periphery, and the annular protrusion is fitted and locked in a fitting groove provided on the inner periphery of the grommet body.

  As described above, in the first invention, a linear sliding contact portion projects from the outer surface of the folded portion of the resin inner locking piece, and in the second invention, it is divided into narrow first and second divided locking pieces. By providing an interval, the contact area between the locking piece and the inner peripheral surface of the through hole can be reduced without reducing the grommet fixing force of the locking piece, so that the insertion force can be reduced, Grommet mounting workability can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 5 show a grommet 10 according to a first embodiment of the present invention, and the grommet 10 passes through a through hole H provided in a vehicle body panel P that partitions a vehicle compartment X side and an outdoor Y side of an automobile. It is attached to the wire harness W / H.

  As shown in FIGS. 1 (A) and 1 (B), the grommet 10 is made of rubber or elastomer and has elasticity, and is made of polypropylene and is flexible. It consists of a hard resin inner 12.

  The grommet body 11 is formed by integrally molding a small diameter cylindrical portion 13 into which the wire group of the wire harness W / H is closely attached and inserted, and a large diameter portion 14 continuous with the tip of the small diameter cylindrical portion 13. The enlarged diameter portion 14 has a substantially square cross section, a lip portion 15 projects outwardly from the annular front end surface, and a fitting groove having a U-shaped cross section that engages and locks the resin inner 12 on the inner peripheral surface. 16 is provided around.

  The resin inner 12 includes a peripheral wall portion 17 having a substantially rectangular tube shape in cross section accommodated inside the enlarged diameter portion 14, an annular protrusion 18 projecting from the outer periphery of the rear end side of the peripheral wall portion 17, and the peripheral wall portion A plurality of locking pieces 20 projecting from the outer periphery of the distal end side of 17 are integrally formed. The resin inner 12 is attached to the grommet body 11 by fitting and locking the annular protrusion 18 in the fitting groove 16.

A part of the distal end side of the peripheral wall portion 17 protrudes from the distal end opening of the enlarged diameter portion 14, and the outer periphery of the projecting portion 19 is opposed to the long side and the short side, respectively, as shown in FIG. A total of four locking pieces 20 are provided for each pair.
Specifically, as shown in FIGS. 3 (A) and 3 (B), the locking piece 20 is formed at a folded portion 21 having a spring property bent from the distal end 17a of the peripheral wall portion 17, and at the distal end of the folded portion 21. It consists of a locking claw 22.

  The locking claw 22 is formed by cutting the tip of the folded portion 21 into a step shape, and includes a locking projection 22a and an inner peripheral pressure contact portion 22b.

  The outer surface of the folded portion 21 protrudes so that the center in the width direction becomes a peak, and this peak portion continues linearly from the bent position of the folded portion 21 to the tip side, and the inner peripheral surface of the through hole H. The linear slidable contact portion 23 slidably in contact with is formed. The linear slidable contact portion 23 formed of the mountain top portion has a shape that extends from the center in the width direction to the entire length in the width direction on the tip end side of the folded portion 21.

  When the grommet 10 is mounted and fixed in the through hole H of the vehicle body panel P, the protrusion 19 of the resin inner 12 is inserted into the through hole H from the outdoor Y side as shown in FIG. By locking and fixing the pawl 22 to the periphery of the through hole H on the side of the passenger compartment X, the lip portion 15 of the grommet body 11 is crimped to the periphery of the through hole H of the vehicle body panel P, and the grommet 10 is fixed in a sealed state. .

  In this mounting operation, when the resin inner 12 is inserted into the through hole H, the inner peripheral surface of the through hole H and the outer surface of the folded portion 21 of the locking piece 20 come into contact with each other, and an insertion load is generated. Since the linear sliding contact portion 23 is formed on the outer surface, only the linear sliding contact portion 23 is in contact with the inner peripheral surface of the through hole H, as shown in FIG. Line contact. Accordingly, since the contact area is reduced as compared with the conventional surface contact and the insertion load can be greatly reduced, the grommet 10 can be easily mounted and fixed to the through hole H with a small insertion force, and workability can be improved.

  Further, in order to reduce the insertion force, the width of the folded portion 21 and the locking claw 22 and the hooking allowance are not adjusted, so that the fixing force of the locking piece 20 is increased to a level similar to the conventional level or higher. It is also possible to reduce only the insertion force while maintaining the fixing force of the grommet 10 to the through hole H.

  Further, since the locking claw 22 is formed in a step shape, the locking projection 22a of the locking claw 22 is locked to the periphery of the through hole H on the side of the passenger compartment X as shown in FIG. The inner peripheral pressure contact portion 22b is in pressure contact with the inner peripheral surface of the through hole H while preventing the grommet 10 from rattling.

  In addition, the shape of the linear sliding contact portion 23 of the turned-up portion 21 is replaced with a shape that forms a peak while forming a concave arc, or a triangular cross section as shown in FIG. 6 (A), or FIG. 6 (B). A semicircular cross section as shown in FIG.

7 to 9 show a grommet 30 according to the second embodiment of the present invention.
As shown in FIGS. 7A and 7B, the grommet 30 is formed by attaching a flexible resin inner 32 made of polypropylene and having flexibility inside a grommet body 31 having elasticity formed of rubber or elastomer. .

  The grommet main body 31 is integrally formed with a small-diameter cylindrical portion 33 into which the wire group of the wire harness W / H is closely attached and inserted, and a large-diameter portion 34 continuous with the tip of the small-diameter cylindrical portion 33. The enlarged diameter portion 34 has a circular cross section, and a lip portion 35 protrudes outwardly from the annular front end surface, and a fitting groove 36 having a U-shaped cross section that engages and locks the resin inner 32 on the inner peripheral surface. Around.

  The resin inner 32 includes a circular ring-shaped peripheral wall portion 37 accommodated in the enlarged-diameter portion 34, an annular protrusion 38 projecting from the outer periphery of the peripheral wall portion 37, and the tip of the peripheral wall portion 37. A plurality of locking pieces 40 projecting from the outer periphery on the side are integrally formed. The resin inner 32 is attached to the grommet body 31 by fitting and locking the annular protrusion 38 in the fitting groove 36.

  A part of the distal end side of the peripheral wall portion 37 protrudes from the distal end opening of the enlarged-diameter portion 34, and an outer periphery of the projecting portion 39 is spaced apart at equal intervals in the circumferential direction as shown in FIG. A locking piece forming recess 40 is provided at a location, and the first split locking with a small width L4 is provided in the locking piece forming recess 40 with a gap L3 in the circumferential direction as shown in FIG. 8B. A piece 41A and a second divided locking piece 41B are provided.

  Specifically, as shown in FIG. 8B, the first divided locking piece 41A and the second divided locking piece 41B are each a folded portion 42 having a spring property bent from the tip 37a of the peripheral wall portion 37, and It consists of a locking claw 43 formed by cutting the tip of the folded portion 42 into a step shape. The locking claw 43 is locked to the peripheral edge of the through hole H on the side of the passenger compartment X so as to prevent the grommet 10 from coming out, and the locking claw 43 is pressed against the inner peripheral surface of the through hole H to regulate the backlash of the grommet 10. And an inner peripheral pressure contact portion 43b.

  41 A of 1st division | segmentation locking pieces and the 2nd division | segmentation locking piece 41B are connected with the connection piece 44 which follows the said internal peripheral press-contact part 43b.

  When the grommet 30 is mounted and fixed in the through hole H of the vehicle body panel P, the protrusion 19 of the resin inner 32 is inserted into the through hole H as shown in FIG. The stoppers 41A and 41B are locked and fixed to the periphery of the through hole H on the side of the passenger compartment X, whereby the lip portion 35 of the grommet body 31 is crimped to the periphery of the through hole H of the vehicle body panel P, and the grommet 30 is sealed. Fix it.

  In this mounting operation, the inner peripheral surface of the through hole H and the outer surface of the folded portion 42 of the divided locking pieces 41A and 41B come into contact with each other to generate an insertion load. However, the width L4 of each folded portion 42 is formed narrow. Therefore, the contact width (L4 + L4) with the inner peripheral surface of the through hole H is also narrowed, and the insertion load can be reduced. Thereby, the grommet 30 can be easily mounted and fixed in the through hole H with a small insertion force, and the mounting workability can be improved.

  On the other hand, the first and second divided locking pieces 41A and 41B are provided with a locking claw 43 that affects the fixing force, although a space L3 is provided between the folded portions 42 and 42 that affect the insertion load. The tip side is connected by a connecting piece 44 and is continuously integrated over a width L5 (L4 + L3 + L4). Therefore, the fixing force of the first and second divided locking pieces 41A and 41B acts over the width L5, and the fixing force similar to or higher than the fixing force of the conventional locking pieces can be exhibited. Accordingly, only the insertion force can be reduced while maintaining or increasing the fixing force of the grommet 30 to the through hole H.

  Further, since the first and second divided locking pieces 41A and 41B are connected by the connecting piece 44, half-fitting to the through hole H can be prevented, and workability and accuracy of grommet mounting are ensured. be able to.

The grommet which concerns on 1st embodiment of this invention is shown, (A) is a front view, (B) is sectional drawing. It is a perspective view of the resin inner shown in FIG. The principal part of a resin inner is shown, (A) is a perspective view, (B) is a BB sectional drawing. It is sectional drawing which shows the state which attached and fixed the grommet of FIG. 1 to the through-hole. It is explanatory drawing which shows a state when inserting a resin inner into a through-hole. (A) (B) is sectional drawing which shows the other shape of a linear sliding contact part. The grommet which concerns on 2nd embodiment of this invention is shown, (A) is a front view, (B) is sectional drawing. The resin inner shown in FIG. 7 is shown, (A) is a whole perspective view, (B) is a principal part expansion perspective view. It is explanatory drawing which shows the state which mounted | wore and fixed the grommet shown in FIG. 7 to the through-hole. It is a figure of a prior art example. It is a general | schematic expansion perspective view of the latching piece of a prior art example.

Explanation of symbols

10, 30 Grommet 11, 31 Grommet main body, small diameter cylindrical portion 12, 32 Resin inner 13, 33 Small diameter cylindrical portion 14, 34 Large diameter portion 17, 37 Peripheral wall portion 20 Locking piece 21, 42 Folded portion 23 Linear shape composed of mountain peaks Sliding contact portion 43 Locking claw 41A First divided locking piece 41B Second divided locking piece

Claims (4)

A grommet for inserting and fixing a wire group of a wire harness to be installed in a vehicle and mounting and fixing it in a through hole of a vehicle body panel,
A small-diameter cylindrical portion that is molded with rubber or elastomer, and the wire group is inserted, and a grommet body that includes an enlarged-diameter portion continuously at the tip of the small-diameter cylindrical portion;
It is assembled in the inside of the enlarged diameter part of the grommet main body, and consists of a resin inner made of a resin molded product partly protruding from the tip opening of the enlarged diameter part,
On the peripheral wall from which the inner resin protrudes, there is provided a locking piece for locking to the peripheral edge of the through hole of the vehicle body panel with an interval in the circumferential direction.
Each locking piece is provided with a locking claw by notching the tip of the folded portion bent from the tip of the peripheral wall in a stepped manner, and the outer surface of the folded portion that is in sliding contact with the inner peripheral surface of the through hole is: It protrudes so that the center in the width direction becomes the peak, and a linear sliding contact portion in which the peak is continuous from the bent position to the tip side is formed. A grommet for a wire harness characterized by that. A grommet for inserting and fixing a wire group of a wire harness to be installed in a vehicle and mounting and fixing it in a through hole of a vehicle body panel,
A small-diameter cylindrical portion that is molded with rubber or elastomer, and the wire group is inserted, and a grommet body that includes an enlarged-diameter portion continuously at the tip of the small-diameter cylindrical portion;
It is assembled in the inside of the enlarged diameter part of the grommet main body, and consists of a resin inner made of a resin molded product partly protruding from the tip opening of the enlarged diameter part,
The peripheral wall from which the resin inner protrudes is provided with a locking piece forming recess that is locked to the peripheral edge of the through hole of the vehicle body panel with an interval in the circumferential direction.
A grommet for a wire harness, wherein each of the locking piece forming recesses is provided with a first divided locking piece and a second divided locking piece which are narrow in the circumferential direction and spaced apart.   Each of the first divided locking piece and the second divided locking piece is provided with a locking claw by cutting out the front end of the folded portion bent from the front end of the peripheral wall in a step shape, and the front end side of the folded portion is The grommet for a wire harness according to claim 2, wherein the grommet is connected by a flexible connecting piece.   The resin inner in the grommet body is provided with an annular protrusion from the outer periphery thereof, and the annular protrusion is fitted and locked in a fitting groove provided in the inner periphery of the grommet body. The grommet for wire harnesses of any one of Claims.

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