JP4048992B2 - Grommet - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a grommet, and more particularly, to a grommet that is assembled to a wire harness routed in an automobile and attached to a through hole of a vehicle body panel to protect, waterproof, and dust proof the wire harness at a through hole insertion portion.
[0002]
[Prior art]
A grommet is attached to the wire harness routed from the engine room of the automobile to the passenger compartment, and the grommet is attached to the through hole of the vehicle body panel that separates the engine room and the passenger compartment, thereby protecting the wire harness passing through the through hole. In addition, waterproofing, dustproofing, and sound insulation from the engine room side to the vehicle compartment are made.
[0003]
This type of grommet is often pulled straight in the direction perpendicular to the through-hole in order to insert and lock it in the through-hole of the vehicle body panel, but if there is an interference material near the through-hole of the vehicle body panel, Can't pull the grommet straight.
As a grommet in the case described above, the present applicant has previously provided a grommet 1 shown in FIG. 4 in JP-A-2002-233035.
[0004]
The grommet 1 includes a small-diameter cylindrical portion 2 and a large-diameter cylindrical portion 4 continuous to the small-diameter cylindrical portion 2, and an annular shape sandwiched between an inclined wall 5a and a vertical wall 5c on the large-diameter side of the large-diameter cylindrical portion 4. The vehicle body locking groove 5b is provided to refract the axis of the small diameter cylindrical portion 2 and the axis of the large diameter cylindrical portion 4, and the protruding amount of the inclined wall 5a from the outer peripheral surface of the large diameter cylindrical portion is small. While making the inclined wall 5a-2 on the refracting side of the portion 2 small, the protruding amount of the inclined wall 5a-1 on the opposite side is made large.
The grommet 1 is pulled in the Y direction, and the periphery of a through hole provided in the vehicle body panel is fitted into the groove 5b for locking the vehicle body of the grommet 1 so that the grommet 1 is locked to the vehicle body panel.
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-233035
[Problems to be solved by the invention]
However, after the grommet 1 is locked to the vehicle body panel, if a force in the direction opposite to the Y direction is applied to the grommet 1, the depth of the vehicle body locking groove 5b is uniform throughout, so that the force is easily transmitted. There is a problem that the groove 5b-2 for locking the vehicle body on the refraction side is disengaged from the peripheral portion of the through hole, and the grommet 1 is disengaged from the vehicle body panel.
Further, in order to prevent the grommet 1 from coming off due to the force in the direction opposite to the Y direction, it may be possible to deepen the groove 5b for locking the vehicle body. However, the protruding amount of the inclined wall 5a increases, and it faces the refracting side. Since the pulling force is difficult to be transmitted to the side where the grommet is inserted, there is a problem that the insertion force required for the grommet insertion operation is increased and workability is deteriorated.
[0007]
This invention is made | formed in view of the said problem, and makes it the subject to reduce the insertion force required at the time of diagonal insertion of a grommet, and to raise the locking force of the grommet locked to the vehicle body panel.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is different in the axial direction from the enlarged diameter cylindrical portion provided with an annular concave portion for locking the vehicle body on the larger diameter side and the reduced diameter end of the enlarged diameter cylindrical portion. A small-diameter cylindrical portion that is bent and continuous, and is attached by inserting a wire harness through the small-diameter cylindrical portion and the large-diameter cylindrical portion, pulling the small-diameter cylindrical portion side, and inserting it into the through hole of the vehicle body panel. In the grommet that attaches the recess to the through hole,
While the diameter of the bottom surface of the annular recess is uniform over the entire circumference, the side walls on the reduced diameter side of the both side walls sandwiching the bottom surface of the annular recess have different heights from the bottom surface in the circumferential direction. the height of the sidewall of the reduced diameter side of the refraction side provides a grommet to the other side of said large cities Tei Rukoto than the height of the side wall and the refraction side.
[0009]
With the above configuration, the grommet pulling force is difficult to be transmitted to the annular recess on the opposite side to the refracting side, but the height from the bottom surface of the reduced diameter side wall opposite to the refracting side is reduced. The peripheral edge of the hole can easily get over the tip of the reduced diameter side wall, and the peripheral edge of the through hole can be dropped into the annular recess with a small insertion force.
In addition, the height from the bottom surface of the side wall on the reduced diameter side on the refracting side is larger than the height of the side wall on the opposite side to the refracting side, but because the tensile force of the grommet is easily transmitted, The insertion force for dropping the peripheral edge of the through hole is not so great. Accordingly, the grommet can be easily attached to the through hole of the vehicle body panel with a small insertion force.
[0010]
Even when a force opposite to the pulling direction is applied to the grommet, the peripheral side portion of the through hole is not easily detached from the annular recess because the height of the side wall on the refractive side where the force is easily transmitted is increased.
In addition, the said refractive side means the side where a small diameter cylinder part and an enlarged diameter cylinder part adjoin most.
[0011]
The diameter of the side wall tip on the reduced diameter side that increases the height from the bottom surface of the annular recess is 0.5 to 3.0% larger than the diameter of the side wall tip on the reduced diameter side that decreases the height. It is preferable.
If it is smaller than 0.5%, the effect of increasing the locking force by increasing the side wall on the reduced diameter side cannot be obtained sufficiently, and the perimeter of the through hole when a force opposite to the pulling direction is applied to the grommet This is because the portion is easily detached from the annular concave portion on the refraction side. On the other hand, if the ratio is larger than 3.0%, the side wall on the refraction side becomes too high, and the insertion force for locking the annular recess on the refraction side to the peripheral portion of the through hole becomes large.
[0012]
The side wall on the reduced diameter side of the annular recess is preferably made higher in the range of 60 to 180 ° on the refracting side with the axis of the enlarged diameter cylindrical portion as the center.
If the angle is smaller than 60 °, the effect of increasing the locking force by increasing the side wall on the reduced diameter side on the refracting side cannot be obtained sufficiently, and when the grommet is subjected to a force opposite to the pulling direction, This is because the peripheral edge portion is easily detached from the annular concave portion on the refraction side. On the other hand, if the angle is larger than 180 °, the outer diameter of the tip of the side wall opposite to the refracting side becomes large, and the grommet insertion force cannot be reduced.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show an embodiment of the present invention.
The grommet 10 is integrally formed of rubber or elastomer, has a small-diameter cylindrical portion 12, a large-diameter cylindrical portion 14 that is continuous with the small-diameter cylindrical portion 12 and has an axis X that is refracted from the axis R of the small-diameter cylindrical portion 12. It consists of the annular recessed part 15 provided in the outer peripheral surface of the large diameter side of this enlarged diameter cylinder part 14. As shown in FIG. Further, a web-like shape that is continuous with the outer peripheral surface of the small-diameter cylindrical portion 12 and the outer peripheral surface of the large-diameter cylindrical portion 14 on the side of refraction where the outer peripheral surface of the small-diameter cylindrical portion 12 and the outer peripheral surface of the enlarged-diameter cylindrical portion 14 are closest A triangular piece 13 is provided.
[0014]
The small-diameter cylindrical portion 12 includes a first small-diameter cylindrical portion 12a, an enlarged diameter step portion 12b continuous with the first small-diameter cylindrical portion 12a, and a second small-diameter cylinder portion 12c continuous with the enlarged diameter step portion 12b. The first small-diameter cylindrical portion 12a is provided with three ridges 12d in an annular shape on the inner peripheral surface.
[0015]
The locking recess 15 provided annularly on the large diameter side of the enlarged diameter cylindrical portion 14 includes a vertical wall 15c protruding to the large diameter side and a reduced diameter side wall 15a opposed to each other across the bottom surface 15b. The outer peripheral surface of the reduced-diameter side wall 15a is inclined so as to increase in diameter toward the small-diameter cylindrical portion 12 side, and from the reduced-diameter side wall tip 15d, which is the end portion on the small-diameter cylindrical portion 12 side of the reduced-diameter side wall 15a. The outer peripheral surface of the enlarged diameter cylindrical portion 14 is inclined so as to reduce its diameter up to a continuous position with the portion 12. A seal lip 15c-2 is provided annularly in the axial direction of the grommet 10 at the outer diameter end of the side surface 15c-1 of the vertical wall 15c.
[0016]
The outer diameter of the side wall tip 15d on the reduced diameter side of the locking recess 15 is partially changed. Specifically, the outer diameter of the side wall tip 15d-1 corresponding to 45 ° from the side of the side wall tip 15d to the left and right sides is set to a diameter of 76.0 mm (h1 = 38.0 mm) about the axis X, and the side wall tip 15d. −1, the outer diameter of the remaining side wall tip 15d-3 is 75.0 mm (h2 = 37.5 mm) centering on the axis X, with the side wall tip 15d-2 corresponding to a range of 10 ° on both the left and right sides. It is said. That is, the outer diameter of the side wall tip 15d-1 is about 1.3% larger than the outer diameter of the side wall tip 15d- 3 . Further, the diameter of the bottom surface 15b is uniform over the entire circumference, and the outer diameter of the side wall tip 15d-1 on the refraction side is made larger than the outer diameter of the side wall tip 15d-3 on the side opposite to the refraction side. Is made larger than the side wall height on the side opposite to the refractive side.
The side wall tip 15d-2 sandwiched between the side wall tip 15d-1 and the side wall tip 15d-3 is a side wall tip 15d as an arc connecting the end of the side wall tip 15d-1 and the end of the side wall tip 15d-3. -1 and the diameter difference between the side wall tip 15d-3 are corrected.
[0017]
Next, the mounting operation of the grommet 10 to the vehicle body panel P will be described.
First, the wire harness W / H is inserted into the hollow portions of the small diameter cylindrical portion 12 and the enlarged diameter cylindrical portion 14 of the grommet 10 and fixed to the first small diameter cylindrical portion 12a with the tape T.
Next, while the grommet 10 is crushed by hand in the direction of the white arrow in FIG. 3 (A), the grommet 10 is pushed in from the large diameter side of the grommet 10 through the through hole H, and is moved to the vehicle interior side (N).
[0018]
Next, as shown in FIG. 3B, the small-diameter cylindrical portion 12 side of the grommet 10 is pulled back to the vehicle outer side (M). At this time, almost no pulling force is required until the peripheral portion of the through hole H reaches a portion having the same outer diameter as the inner diameter of the through hole H of the vehicle body panel P. As shown in FIG. When the through hole H comes into contact with the diameter-expanded cylindrical portion 14, a feeling of moderation is generated there.
[0019]
As shown in FIG. 3 (D), the operator pulls the grommet 10 obliquely from the moderation position, that is, pulls the grommet 10 to the refracting side of the small-diameter cylindrical portion 12, so that the peripheral portion of the through hole H is at the tip of the side wall. 3d is bent inward, passes through the side wall tip 15d, and as shown in FIG. 3 (E), is dropped into the annular recess 15 so as to be sandwiched between the reduced diameter side wall 15a and the vertical wall 15c. The At this time, the inner peripheral surface of the vehicle body panel P is in contact with the seal lip 15c-2 of the vertical wall 15c, so that waterproofness is ensured.
[0020]
With the above configuration, the pulling force of the grommet 10 is difficult to be transmitted to the side wall tip 15d-3 opposite to the refracting side, but since the outer diameter of the side wall tip 15d-3 is reduced, the peripheral portion of the through hole H is It becomes easy to get over the side wall tip 15d-3, and the peripheral edge of the through hole H can be dropped into the annular recess 15 with a small insertion force. Further, the outer diameter of the side wall tip 15d-1 on the refraction side is larger than that of the side wall tip 15d-3, but since the tensile force of the grommet 10 is easily transmitted, the peripheral portion of the through hole H is inserted into the annular recess 15 on the refraction side. The insertion force does not increase to drop Thereby, the grommet 10 can be easily mounted in the through hole of the vehicle body panel with a small insertion force.
Further, even when a force opposite to the pulling direction is applied to the grommet 10, the outer diameter of the side end 15d-1 on the refraction side where force is easily transmitted is increased, so that the peripheral portion of the through hole H can be easily removed from the annular recess 15. It will not come off.
[0021]
【The invention's effect】
As is clear from the above explanation, according to the present invention, in the grommet in which the small diameter cylindrical portion and the large diameter cylindrical portion are refracted, the tensile force of the grommet is not easily transmitted to the annular concave portion on the opposite side to the refractive side. Since the outer diameter of the side wall tip on the diameter-reduced side opposite to the refracting side is made smaller, the peripheral edge of the through hole can easily get over the front end of the side wall, and the peripheral edge of the through hole can be dropped into the annular recess with a small insertion force. Can do.
The outer diameter of the tip of the side wall on the refracting side is larger than the outer diameter of the tip of the side wall on the side opposite to the refracting side, but since the pulling force of the grommet is easy to be transmitted, The insertion force to drop the will not increase. Accordingly, the grommet can be easily attached to the through hole of the vehicle body panel with a small insertion force.
Even when a force opposite to the pulling direction is applied to the grommet, the outer diameter of the end of the side wall on the refraction side where force is easily transmitted is increased, so that the peripheral edge of the through hole is not easily detached from the annular recess.
[Brief description of the drawings]
FIG. 1 is a rear view of a grommet according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the grommet taken along line II.
FIGS. 3A to 3E are diagrams showing a procedure for mounting a grommet on a vehicle body panel. FIGS.
FIG. 4 is a diagram showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Grommet 12 Small diameter cylinder part 14 Diameter expansion cylinder part 15 Annular recessed part 15a Side wall 15b by the side of reduction diameter Bottom surface 15c Vertical wall 15d Side wall tip P Body panel H Through hole W / H Wire harness

Claims (1)

A diameter-enlarging cylindrical part provided with an annular recess for locking the vehicle body on the large-diameter side, and a diameter- reducing end of the diameter-enlarging cylindrical part, and a small-diameter cylindrical part that is bent and continued in a different axial direction from the diameter-enlarging cylindrical part. A grommet for inserting and attaching the wire harness to the small-diameter cylindrical portion and the large-diameter cylindrical portion, pulling the small-diameter cylindrical portion side, and inserting the annular recess into the through-hole by inserting the through-hole in the vehicle body panel.
While the diameter of the bottom surface of the annular recess is uniform over the entire circumference, the side walls on the reduced diameter side of the both side walls sandwiching the bottom surface of the annular recess have different heights from the bottom surface in the circumferential direction. the height of the sidewall of the reduced diameter side of the refraction side, the grommet to the other side of said large cities Tei Rukoto than the height of the side wall and the refraction side.

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