JP2002112439A - Grommet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease a locking force of one-motion grommet which is locked in a through hole of a vehicle body panel by a push from one direction. SOLUTION: An expanded diameter cylinder part is formed between the first and second small-diameter cylinder parts disposed on the both sides of the length direction. The expanded diameter cylinder part is formed in a shape continuing from the large-diameter part to conical part in an axial direction and in an oval ring shape in a perpendicular direction. A lightening part is formed by being expanded forward from the back end surface of the expanded diameter cylinder part on the side in continuity with the second small-diameter cylinder part. The expanded diameter cylinder part is branched to an outer cylinder and an inner cylinder in continuity with the second small-diameter cylinder part. A recessed part for locking a vehicle body is provided by being extruded opposing a sloped wall and vertical wall on the outer circumferential surface of the outer cylinder. The back end surface of the outer cylinder constituting the vertical wall is provided with a diameter decreasing notch in positions corresponding to the four corners of the ellipse.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a grommet,
More specifically, it is mounted on a wire harness routed to an automobile and mounted in a through hole of a vehicle body panel to protect the wire harness in a portion where the through hole is inserted, and to protect the wire harness from water and dust.

[0002]

2. Description of the Related Art Conventionally, a grommet is mounted on a wire harness routed from an engine room of an automobile to a vehicle interior, and a grommet is attached to a through hole of a vehicle body panel that separates the engine room and the vehicle interior. Protection of the wiring harness passing through and waterproofing from the engine room side to the car room,
Dust protection and sound insulation are provided.

[0003] As this type of grommet, there is provided a so-called one-motion grommet in which a body locking recess provided on the outer periphery of the grommet is locked to the peripheral edge of the through hole by simply pushing the grommet into the through hole of the body panel from one direction. Have been. The one-motion grommet has an advantage of good mounting workability. For example, a one-motion grommet shown in FIG. 7 is provided in Japanese Utility Model Laid-Open No. 4-42982.

The grommet 1 has small-diameter cylindrical portions 2 and 3 on both sides.
The vehicle body engaging concave portion 5 is provided on the outer peripheral surface of the large diameter cylindrical portion 4, and the lightening portion 6 is provided on the inner peripheral side of the vehicle body engaging concave portion.
Is provided. The grommet 1 is pushed in the direction of the arrow Q from the engine room (X) side to the vehicle room (Y) side. At this time, the inclined wall 5 a of the vehicle body locking concave portion 5 is bent inward by the lightening portion 6. Through the through hole 9 of the vehicle body panel 8, and after the passage, the inclined wall 5a
Is returned to the original state, and is locked to the vehicle body panel P with the other side wall 5b.

[0005]

SUMMARY OF THE INVENTION The above-mentioned grommet 1
In order to facilitate deformation of the inclined wall 5a at the time of being pushed into the through hole 9, the hollow portion 6 extends beyond the inside of the vehicle body engaging recess 5 from the opening 6a, and has an outer peripheral portion on the back side. The inner end 6b of the hollow portion 6 is bent so as to be bent to the substantially same position as the groove bottom surface 5c of the vehicle body locking concave portion 5.

However, if the lightening portion 6 is configured as described above, when the lightening portion 6 comes into contact with the outer peripheral surface 4a of the enlarged diameter cylindrical portion 4 where the deep end 6b of the lightening portion 6 is located,
Since the outer peripheral wall thickness of the base of the inclined wall 5a is smaller than the inner peripheral wall thickness, the inclined wall 5a is easily deformed outward. As described above, when the inclined wall 5a is deformed outward without being deformed inward, the inclined wall 5a comes into contact with the wall surface 8a on the pushing side of the vehicle body panel 8, and it is difficult to insert the grommet 1 into the through hole 9. Become. That is, the inclined wall 5a is formed by the hollow portion 6 provided to facilitate the deformation of the inclined wall 5a inward.
Are deformed outward in the opposite direction, and the workability of inserting the grommet 1 into the through hole H is deteriorated, and a large insertion force is required.

When the through hole of the vehicle body panel is elliptical, the small-diameter cylindrical portion 3 is usually circular, so that the lightening portion 6 is large on the long axis side and small on the short axis side. If the hollow portion on the long axis side is too large, there is a problem that the peripheral wall provided with the vehicle body locking recess enters the hollow portion and penetrates the through hole.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and when the grommet is pushed into the through hole of the vehicle body panel, the side wall of the vehicle body locking concave portion is easily and reliably deformed inward, so that the grommet mounting workability is improved. Another object of the present invention is to provide a vehicle body panel that is securely locked to a vehicle body panel without penetrating a through hole.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a rubber or elastomer made of rubber or an elastomer which is engaged with a through hole of a vehicle body panel by being inserted into a through hole of a vehicle body panel in a state of being mounted on an automobile wire harness. A grommet, wherein a large-diameter tube portion is provided between a first small-diameter tube portion and a second small-diameter tube portion provided on both sides in the longitudinal direction, and the large-diameter tube portion is continuous from a conical portion to a large-diameter portion in the axial direction. The first small-diameter cylindrical portion is a front portion on the insertion side into the through hole, and the rear portion of the large-diameter cylindrical portion is continuous with the second small-diameter cylindrical portion. Form by extending an annular hollow portion from the end face forward,
The enlarged diameter cylindrical portion is branched into an elliptical outer cylinder and a circular inner cylinder that is continuous with the second small diameter cylindrical portion, and an inclined wall and a vertical wall are protruded from the outer peripheral surface of the outer cylinder so as to face each other. A vehicle body locking concave portion is provided, a base end position of the inclined portion is located outside a deep end of the hollow portion, and the vertical wall has a thick wall extending to a distal end of the outer cylinder. A grommet having a notch for reducing the diameter is provided on the inner periphery of the outer cylinder corresponding to the four corners of the shape.

In the above grommet, since the base end position of the inclined wall contacting the vehicle body panel is located on the outer diameter side from the deep end from the hollow portion, the inclined wall is formed as in the above-described conventional example. It does not deform outward and hit the body panel,
The inclined wall is deformed inward on the side of the hollow portion, so that the pushing operation can be performed smoothly. In addition, when the inclined wall is deformed to the inside of the hollow portion, in the case of an elliptical shape, four corners are stretched and it is difficult to deform in the radially-reducing direction. Since the notch for reducing the diameter is provided, the outer cylinder provided with the inclined portion can be easily deformed toward the hollow portion. Therefore, in one motion grommet,
The grommet can be mounted on the body panel with low insertion force.

The hollow portion has a linear shape whose inner and outer peripheral surfaces are parallel to the axial direction on the opening side located on the inner side of the vertical wall, and on the inner side of the inclined wall, The outer peripheral surface has a linear shape continuing to the opening side, and the inner peripheral surface is inclined so as to be in contact with the outer peripheral surface. As described above, since the lightening portion has a tip opening wider than the inner end, the outer cylinder can easily fall over the lightening portion.

The notch for diameter reduction is cut into the rear end face of the outer cylinder in a V-shape radially from the inner circumference, and is cut in the axial direction into a triangular shape from the apex of the V-shape. ing. When the notch has the above shape, the outer cylinder can be easily deformed inward.

A rib is protruded from the outer peripheral surface of the inner cylinder facing the major axis of the elliptical shape to reduce the space of the lightening portion, and a space between the rib tip sandwiching the lightening portion and the inner peripheral surface of the outer cylinder is provided. The dimensions of
The dimension between the outer peripheral surface of the inner cylinder and the inner peripheral surface of the outer cylinder on the short axis side sandwiching the lightening portion is substantially the same.

Further, since the enlarged diameter portion has an elliptical shape, the hollow portion has a large space on the long axis side. However, since the rib is provided on the outer peripheral surface of the inner cylinder on the long axis side, the vehicle body locking recess. When the outer cylinder provided with is deformed toward the lightening portion side, the amount of deformation is regulated by the rib, preventing the vehicle body locking concave portion from deforming too much inward and penetrating through the through hole of the vehicle body panel. .

[0015]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the grommet 10 of the embodiment is integrally formed of rubber or an elastomer, and has a first small-diameter cylindrical portion 11 at the front part on the insertion side and a small-diameter rear part 12 at the rear side.
The diameter-expanded cylindrical portion 13 is formed between them. Since the through hole of the vehicle body panel for locking the grommet 10 is formed in an elliptical shape, the diameter-enlarged cylindrical portion 13 is also formed in an elliptical annular shape.

As shown in FIG. 2, the grommet 10 has an electric wire of a wire harness W / H along a central axis L of a cylindrical portion connected to the small-diameter cylindrical portion 11, the large-diameter cylindrical portion 13, and the small-diameter cylindrical portion 12. The tape T is wound and fixed while the group W is inserted and the wire group is brought into close contact with the inner peripheral surfaces of the small-diameter cylindrical portions 11 and 12.
A sealed sound insulation space S is provided between the inner peripheral surface of the diameter-enlarged cylindrical portion 13 and the wire group W. Grommet 1 above
0 is attached to the wire harness W / H, and is pushed from the engine room (X) into the through hole 9 of the vehicle body panel 8 as shown by the arrow Q, and is provided on the outer peripheral surface of the enlarged-diameter tube portion 3 in one motion. The vehicle body locking recess 16 is locked to the peripheral edge of the through hole 9.

The diameter-enlarging cylindrical portion 13 includes a conical portion 13a that expands while being inclined continuously with the first small-diameter cylindrical portion 11, and a conical portion 1a.
And a large-diameter portion 13b continuous with the third portion. Large diameter part 13b
The diameter of the inner peripheral surface 13b-1 is reduced toward the second small-diameter cylindrical portion 12, and the outer peripheral surface 13b-2 is inclined so as to increase the diameter toward the rear end at a small angle. It is straight.

The large diameter portion 13b has a rear end face 13b.
-3 is provided annularly, and the lightening portion 15
As a result, the large-diameter portion 13b having an elliptical annular cross section is branched into an outer cylinder c and an inner cylinder 13d having an annular cross section, and the inner cylinder 13d is connected to the second small-diameter cylindrical portion 12.

The outer cylinder 13c is provided with the vehicle body locking recess 16 as described above. The vehicle body locking recess 16 is
Inclined wall 16a protruding from large diameter portion outer peripheral surface 13b-2
And a vertical wall 16b facing the inclined wall 16a,
A groove bottom 16c is formed between the inclined wall 16a and the vertical wall 16b.
Therefore, the groove bottom surface 16c is formed on the large diameter portion outer peripheral surface 13c.
b-2 (outer cylinder outer peripheral surface). The vertical wall 16b is thicker than the inclined wall 16c and extends to the rear end of the outer cylinder.

The opening side 15a of the hollow portion 15 located inside the vertical wall 16b has an outer peripheral surface (an inner peripheral surface of the outer cylinder) 15a.
a-1 and the inner peripheral surface 15a-2 (the outer peripheral surface of the inner cylinder) are linearly parallel to the axial direction, and the inner peripheral surface is continuous with the outer peripheral surface of the second small-diameter cylindrical portion 12. On the other hand, the inner peripheral surface 15b-1 is straightened with the outer peripheral surface 15b-1 being continuous with the opening outer peripheral surface 15a-1.
-2 is inclined in the outer peripheral direction to have a substantially triangular cross section. That is, the inner side 15b of the lightening portion is not inclined to the outer peripheral side as in the above-described conventional example, and is therefore located inside the groove bottom surface 16c of the vehicle body engaging concave portion 16.

The boundary between the opening side 15a and the back side 15b is located at a position corresponding to the groove bottom surface 16c of the vehicle body engaging concave portion 16.
Further, the back end position P1 on the back side 15b is located at the inclined wall 16c.
Is located further back than the base end position P2.

Further, a notch 21 for reducing the diameter is formed on the outer end face of the thick outer cylinder 13 where the vertical wall 16b is located, at the inner periphery at the end corresponding to approximately four corners of the elliptical shape. .
The notch 21 for diameter reduction is cut into a V shape when viewed from the rear end face of the outer cylinder 13c, and is formed as a triangular notch inclined from the vertex of V to the inner peripheral surface when viewed in the axial direction.

In the lightening portion 15, the inner cylinder 13d has an annular shape and the outer cylinder 13c has an elliptical shape. Are narrowed on both sides 15y. To make the gap dimension on the long axis side substantially the same as the gap dimension D on the short axis side, the inner cylinder 13d
A pair of ribs 20 are formed on the outer peripheral surface of (i.e., the inner peripheral surface of the lightening portion 15) along the entire length in the axial direction from the back end to the opening end of the lightening portion 15. That is, the dimension E between the tip of the rib 20 and the inner peripheral surface of the outer cylinder is substantially the same as the dimension D (D ≒ E).

The clearance dimensions D and E are such that the outer cylinder 13c falls into the hollow portion 15 and the outer peripheral surface of the inner cylinder 13d on the short axis side.
On the long axis side, the outer diameter of the vertical wall 16b is larger than the inner diameter of the through hole 9 of the vehicle body panel 8 even at the time of the maximum deformation in contact with the tip of the projection 20, so that the vertical wall 16b cannot pass through the through hole 9.

The grommet 10 having the above structure is attached to the wire harness W / H as shown in FIG.
A grommet mounting operation for pushing the engine room (X) into the vehicle room (Y) into the through hole 9 will be described.

When the grommet 10 is pushed into the through hole 9 from the first small-diameter cylindrical portion 11, the inner diameter of the through hole 9 is substantially the same as the outer diameter of the large diameter portion 13b. I can do it. When it reaches the large diameter portion 13b, the through hole 9
It passes while sliding on the inner peripheral surface of.

As shown in FIG. 4, when the inclined wall 16a of the vehicle body engaging concave portion 16 protruding from the outer peripheral surface of the large diameter portion hits the vehicle body panel 8, the outer cylinder 13 is supported by the back end P1 of the hollow portion 15 as a fulcrum.
c is deformed inward so as to enter the lightening portion 15 side. At this time, the outer cylinder 13c is deformed while being reduced in diameter inside the thick vertical wall 16b on the rear end side of the outer cylinder 13c.
Are provided at the four corners, so that the outer cylinder 13c can be deformed while being smoothly reduced in diameter while being thick.

When the inclined wall 16a hits the vehicle body panel 8 in this manner, the outer cylinder 13c is deformed inward.
6a can easily pass through the through hole 9 with a low insertion force. When the vehicle body panel 8 hits the inclined wall 16a, first, the inner cylinder 13d is deformed inward and the outer cylinder 13c is not deformed outward. When the vehicle body panel 8 comes into contact with the inclined wall 16a, The outer cylinder 13c is deformed inward and passes through the through hole 8.

When the outer cylinder 13c is deformed so as to fall into the hollow portion 15, the gap on the long axis side is large, but the rib 2
0 suppresses deformation. The deformation amount in contact with the rib 20 is the same as the maximum deformation amount on the short axis side. Outer cylinder 13c
Is deformed to the maximum and abuts on the rib 20, the outer diameter of the vertical wall 16b is larger than the inner diameter of the through hole 9, so that the vertical wall 16b does not penetrate through the through hole 9, and It can be brought into contact with the insertion side wall surface 9a of the vehicle body panel 9.

When the inclined wall 16a passes through the through-hole 9, it returns to its original shape, sandwiches the vehicle body panel 8 between the inclined wall 16a and the vertical wall 16b, and brings the inner peripheral surface of the through-hole 9 into contact with the groove bottom surface 16c. In this state, the grommet 10 is attached to the vehicle body panel 8.

As described above, the grommet 10 is pushed in one direction Q from the engine room side in one motion.
It can be locked while being inserted through the through hole 9 of the vehicle body panel 8.

[0032]

As is apparent from the above description, in the grommet according to the present invention, the position of the hollow portion is set to the inner diameter side from the base end position of the inclined wall which is brought into contact with the vehicle body panel and deformed inward. Therefore, the inclined wall is always deformed inward on the side of the hollow portion, and the grommet pushing operation can be performed smoothly with low insertion force. In addition, since the outer cylinder provided with the vehicle body locking recess is provided with notches for reducing the diameter at the four corners, the diameter can be reduced smoothly at the time of deformation, and the insertion force required for mounting the grommet can be further reduced. it can.

Moreover, the through hole of the vehicle body panel has an elliptical shape, the hollow portion provided on the grommet has an elliptical shape, and even if the clearance between the hollow portions on the long axis side is large, a convex portion is provided from the inner cylinder. Therefore, the fall of the outer cylinder having the vehicle body locking concave portion protruding can be restricted. Therefore, the vehicle body panel cannot be locked in the vehicle body locking recess and the grommet can be prevented from penetrating through the through hole.

[Brief description of the drawings]

FIG. 1 is a side view of a grommet according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

FIG. 4 is an enlarged view of a main part.

FIGS. 5A and 5B are views showing notches for diameter reduction.

FIG. 6 is a cross-sectional view showing a state where the grommet is mounted on a vehicle body panel.

FIGS. 7A and 7B are cross-sectional views showing a conventional example.

[Explanation of symbols]

 Reference Signs List 8 body panel 9 through hole 10 grommet 11 first small-diameter cylindrical part 12 second small-diameter cylindrical part 13 large-diameter cylindrical part 13a conical part 13b large-diameter part 13c outer cylinder 13d inner cylinder 15 lightening part 15a opening side 15b back side 16 Locking recess 16a Inclined wall 16b Vertical wall 20 Rib 21 Notch for reducing diameter W / H Wire harness W Wire group

Claims (3)

[Claims] 1. A grommet made of rubber or an elastomer, which is engaged with a through hole of a vehicle body panel by an insertion operation from one direction in a state where the grommet is mounted on a wire harness for an automobile, and has first small diameters provided on both sides in a length direction. An enlarged diameter cylindrical portion is provided between the cylindrical portion and the second small diameter cylindrical portion, and the enlarged diameter cylindrical portion has a shape that is continuous from the conical portion to the large diameter portion in the axial direction, and has an elliptical ring shape in the direction perpendicular to the axis, The first small-diameter cylindrical portion is formed as a front portion on an insertion side into the through hole, and an annular hollow portion is formed to extend forward from a rear end surface of the large-diameter cylindrical portion that is continuous with the second small-diameter cylindrical portion. Then, the enlarged-diameter cylinder portion is branched into an elliptical outer cylinder and a circular inner cylinder continuous with the second smaller-diameter cylinder portion, and the inclined wall and the vertical wall face each other on the outer peripheral surface of the outer cylinder. And the base end position of the inclined portion is located outward from the back end of the hollow portion, and A grommet in which the straight wall has a thick wall extending to the tip of the outer cylinder, and a notch for reducing the diameter is formed from the tip on the inner periphery of the outer cylinder corresponding to the four corners of the elliptical ring shape. 2. The lightening portion has a linear shape in which an inner peripheral surface and an outer peripheral surface are parallel to an axial direction on an opening side located inside the vertical wall, and a rear side located inside an inclined wall. In this case, the outer peripheral surface is formed in a straight line continuous with the opening side, and the inner peripheral surface is inclined so as to be in contact with the outer peripheral surface.
The grommet according to claim 1, wherein the grommet is cut into a shape, and is cut in a triangular shape from an apex of the V shape in the axial direction. 3. A rib is provided on an outer peripheral surface of the inner cylinder, which is opposite to the major axis of the elliptical shape, to project a rib to reduce the space of the lightening portion, and to provide a rib tip sandwiching the lightening portion and an inner periphery of the outer cylinder. The grommet according to claim 1 or 2, wherein a dimension between the surfaces is substantially the same as a dimension between an outer peripheral surface of the inner cylinder and an inner peripheral surface of the outer cylinder on the short axis side sandwiching the lightening portion.