JP2012239266A - Grommet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance sound insulating performance of a grommet.SOLUTION: A grommet comprises: a split cylindrical part projecting from the circumference of a through hole for a wiring harness arranged at the center of grommet closing walls; and a slit being cut in from the circumference of the through hole for a wiring harness toward the outer periphery. Along each end edge of the closing walls separated by the slit, fitting walls opposing to each other are arranged so as to protrude in the axial direction and/or the radial direction. When a displacement in the axial direction and/or the radial direction occurs at the both end edges sandwiching the slit, some portions of the fitting walls oppose to and contact each other.

Description

  The present invention relates to a grommet that is externally mounted on a wire harness that is routed in a vehicle, and in particular, in a grommet that is mounted in a through hole of a vehicle body panel that partitions an engine room and a vehicle compartment, the sound insulation performance from the engine room side to the vehicle compartment is improved About grommets.

  Recently, in order to maintain the quietness in the passenger compartment, there is a demand for a grommet having a high sound insulation function that prevents transmission of noise from the engine compartment to the passenger compartment. As this type of grommet with improved sound insulation, the present applicant has provided a grommet 100 shown in FIGS. 11A and 11B in Japanese Patent Application Laid-Open No. 2010-120615.

The grommet 100 includes a small-diameter cylindrical portion 101 that penetrates the wire harness 120 in close contact with an end of an enlarged cylindrical portion 103 that is provided with an annular body locking recess 102 on the outer periphery. A closed wall 104 is provided at the other end, and the inside of the enlarged diameter cylindrical portion 103 is formed as a hollow air layer 105 so that noise transmitted from the engine room side is absorbed by the air layer 105 to reduce the noise. The closing wall 104 is provided with a central wire harness insertion hole 106 and diametrical slits 108 from both sides of the wire harness insertion hole 106. The slit 108 is indispensable for taking out the core necessary for forming the enlarged diameter cylindrical portion 103 when the grommet is molded. Further, a halved tape winding tube portion 109 projects from the periphery of the wire harness insertion hole 106 of the closing wall 104.
After passing the wire harness 120 through the grommet 100, the adhesive tape T1 is wound around the tip of the small-diameter tubular portion 101 and the outer periphery of the wire harness 120, and the adhesive tape T2 is wound around the outer periphery of the tape winding tubular portion 109 and the wire harness 120. ing.

JP 2010-120615 A

As described above, it is necessary to provide the slit 108 in the closing wall 104. When the slit 108 is present, as shown in FIGS. When the tape winding cylinder 109 is wound around the wire harness 120 with the adhesive tape T2, a gap is generated in the half tape winding cylinder 109, and a gap 108h that causes sound leakage in the slit 108 is likely to occur.
In addition, even when the wire harness coming out from the half-tape winding tube portion 109 of the grommet 100 is bent sharply, a gap 108h in which sound leakage occurs in the slit 108 is likely to occur.

  The present invention intends to solve the above-mentioned problem, and it is an object to improve the sound insulation performance of the grommet by preventing a gap where sound leakage occurs in the slit provided in the closed wall forming the sound insulation air layer of the grommet. It is said.

In order to solve the above-mentioned problems, the present invention provides a small-diameter cylindrical portion that is molded from rubber or elastomer and that is inserted in close contact with a wire harness; A diameter-enlarging cylindrical portion provided annularly, a closing wall continuous to the inner periphery of the large-diameter side end of the diameter-enlarging cylindrical portion, a wire harness through hole provided in the center of the closing wall, and the wire harness through hole A grommet provided with a slit cut from the peripheral edge of the wire harness through-hole and projecting from the peripheral edge of the wire harness toward the outer periphery,
Along each edge of the closed wall separated by the slit, a mating wall protruding in the axial direction and / or radial direction is provided oppositely, and the axial direction or / and radial position is provided on both side edges sandwiching the slit. There is provided a grommet configured such that any part of the mating wall comes into contact with each other when a shift occurs.

Specifically, the mating wall is a mating wall that protrudes outward and inward in the axial direction from the edges of the divided closed walls on both sides, and the mating walls are provided facing each other.
As described above, when the facing walls protruding inward and outward are provided opposite to both side edges sandwiching the slit, even when the split cylinder part is displaced inward and outward when the split cylinder part and the wire harness are wound with the adhesive tape, Any part of the protruding mating wall can be brought into contact with and opposed to prevent the slit from being opened. As a result, it is possible to prevent a gap in which sound leakage occurs.

Alternatively, the mating wall projects an outer L-shaped mating wall projecting outward in the axial direction from one end edge divided by the slit and then refracting in the other radial direction, Superimposing the radial refracting part on the outer surface of the other closing wall; and
An inner L-shaped mating wall that protrudes inward in the axial direction from the other edge separated by the slit and then refracted in the one radial direction protrudes, and the refracting portion in the radial direction is It is configured to overlap with the inner surface of the closed wall.

  As described above, a configuration in which an L-shaped mating wall projects along the edge of the segmented closing wall sandwiching the slit, and the radial refracting portions of the mating wall overlap the inner and outer surfaces of the opposing closing wall; Then, even if the split cylinder portion is displaced from the wire harness and wound with the adhesive tape, it is possible to prevent the slit from opening and generating a gap in which sound leakage occurs.

The slits are provided in the diametrical direction, and each of the divided closed walls is provided with an outer L-shaped mating wall at one radial portion, and an inner L-shaped mating wall is provided at the other radius portion, and provided opposite to each other. The outer L-shaped mating wall and the inner L-shaped mating wall may be provided oppositely at the radial portions on both sides.
As described above, if the overlapping surface is reversed in the radial direction in the radial direction, the slit can be made more difficult to open.

Alternatively, the mating wall includes a mating wall projecting outward or inward in the axial direction from an end edge of one closing wall divided by the slit, and an outer direction in the axial direction from the end edge of the other closing wall. And a mating wall that protrudes inward and is provided with a refracting portion in the radial direction from the inner or outer protruding end,
The protruding portions in the axial direction are overlapped with each other, and the radial refracting portion of the other mating wall is overlapped with the inner surface or the outer surface of the one divided edge.

  Alternatively, the closed wall is made thick, a slit provided in the closed wall is refracted, and an edge of one closed wall divided by the slit is an outer mating wall in which an outer thick part protrudes in the radial direction. On the other hand, the edge of the other closing wall is an inner mating wall in which the inner thick portion protrudes in the radial direction, and the outer mating wall and the inner mating wall are stacked in the thickness direction of the closing wall.

As described above, the closing wall is thick and the slit is refracted to provide the mating wall without protruding from the closing wall in the axial direction.
By making the closing wall thick, the slit is slightly difficult to open, but by not providing a mating wall protruding in the axial direction from the slit, molding becomes easy.

The facing surface of the mating wall with the other side is preferably a satin surface or an uneven surface.
When the satin treatment is applied, the frictional force increases and slipping can be prevented. In addition, slipping can be reliably prevented when the concave and convex portions are processed so as to be fitted to each other.

  Further, the slits provided in the closed wall are one slit in the diametrical direction extending on both sides in the radial direction of the split cylinder part, three slits provided at intervals of 120 degrees, and 4 provided at intervals of 90 degrees. Any of the slits of a book may be sufficient, and the said alignment wall is protrudingly provided along the edge parted by these each slit.

  As described above, when the mating walls are provided facing both side edges of the slit extending in the outer diameter direction from the split cylinder portion provided in the center of the closing wall of the grommet, the split cylinder portion and the wire harness are adhered. Even if the split cylinder portion is displaced when it is wound with tape, the opposing mating walls can be overlapped with each other, so that it is possible to prevent the occurrence of a gap in which sound is leaked due to a wide opening of the slit.

It is sectional drawing which shows the state which externally fitted the grommet of 1st Embodiment to the wire harness, and was mounted | worn with the through-hole of the vehicle body panel. It is a side view by the side of the closed wall of the grommet of the said 1st Embodiment. (A) is the sectional view on the AA line of FIG. 2, (B) is the BB arrow line view of FIG. (A) (B) (C) is drawing which shows the effect | action of the mating wall when position shift arises in the division | segmentation closed wall which pinches | interposes a slit in the grommet of 1st Embodiment. (A) (B) shows the modification of 1st Embodiment and is sectional drawing of a mating wall. The grommet of 2nd Embodiment is shown, (A) is a side view by the side of a closed wall, (B) is CC sectional view taken on the line of (A). The modification of the grommet of 2nd Embodiment is shown and it is the DD sectional view taken on the line of FIG. 6 (A). (A) is sectional drawing which shows the mating wall of the grommet of 3rd Embodiment, (B) is sectional drawing which shows the modification of this 3rd Embodiment. The grommet of 4th Embodiment is shown, (A) is a side view by the side of a closed wall, (B) is the EE sectional view taken on the line of (A), (C) is the FF sectional view taken on the line of (A). is there. It is a side view by the side of the closed wall of the grommet of 5th Embodiment. (A) (B) is drawing which shows a prior art example. (A) and (B) are drawings showing conventional problems.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show a grommet 1 (1-A) of the first embodiment.

  As shown in FIG. 1, the grommet 1 is attached to the through-hole H provided in the vehicle body panel P that partitions the engine room and the vehicle compartment of the automobile by covering the wire harness 2. In addition to preventing flooding, it also has a sound insulation function to prevent engine room noise from being transmitted to the passenger compartment. In addition, the application location of the grommet of other embodiment mentioned later is the same as that of the grommet of this 1st Embodiment.

The grommet 1 is an integral grommet formed by injecting rubber or elastomer (EPDM in this embodiment) into a mold.
The grommet 1 has a small-diameter cylindrical portion 10 through which the wire harness is closely inserted, a large-diameter cylindrical portion 12 having a diameter increased from one end of the small-diameter cylindrical portion 10 and an annularly provided body locking recess 11 on the outer peripheral surface; A closed wall 13 continuous to the inner periphery of the large-diameter side end of the enlarged diameter cylindrical portion 12, a wire harness through hole 14 provided in the center of the closed wall 13, and a protrusion from the periphery of the wire harness through hole 14. The halved cylindrical portion 15 (15A, 15B) and the diametrical slit 20 cut radially from the peripheral edge of the wire harness through-hole 14 toward the outer periphery, and the closed wall 13 is divided into two divided closed walls 13A and 13B. doing. The slit 20 includes slits 20 a and 20 b on both sides in the radial direction with the wire harness through hole 14 interposed therebetween.

  A mating wall projecting on both sides of the outer Lo and the inner Li in the grommet axial direction L from the end edges 13Ae and 13Be along the entire length of the opposing radial end edges of the divided closed walls 13A and 13B divided by the slit 20 16A and 16B are provided facing each other. Both ends of the mating walls 16A and 16B in the inner and outer directions are tapered.

The projecting height H1 of each of the outward projecting portions 16A-1 and 16B-1 of the mating walls 16A and 16B is set to about ¼ to ３ of the height of the half cylinder portion 15. Moreover, the both ends of each half cylinder part 15A, 15B and the edge of outward protrusion part 16A-1, 16B-1 are made continuous.
The inward projecting height H2 of the inward projecting portions 16A-2 and 16B-2 is equal to the outward projecting height H1.
In the present embodiment, the height of the half cylinder portion 15 is 25 mm, the height H1 of the outward projection and the height H2 of the inward projection are 6 mm.

  The mating walls 16A and 16B projecting opposite to each other along the edge divided by the slit 20 are brought into contact with each other to close the slit 20, and the hollow portion surrounded by the closing wall 13 and the enlarged diameter cylindrical portion 12 is sealed. The sound insulation air layer 18 is formed.

The wire harness 2 is assembled to the grommet 1 by inserting the wire harness 2 into the grommet 1 while expanding the small-diameter cylindrical portion 10 with an expanding jig and through the half-divided cylindrical portion 15 through the enlarged-diameter cylindrical portion 12. .
Thereafter, the adhesive tape T <b> 1 is wound around and secured to the outer periphery of the wire harness 2 from the outer periphery of the distal end of the small-diameter cylindrical portion 10. Further, the adhesive tape T2 is wound and fixed on the other end side from the outer periphery of the half cylinder portions 15A and 15B to the outer periphery of the wire harness 2.

When the adhesive tape T2 is wound around the half cylinder portions 15A and 15B, the half cylinder portions 15A and 15B are displaced in the axial direction L and the radial direction D as shown in FIGS. Is likely to occur. When the positional deviation occurs in this way, the dividing wall 16A on the side of the divided closed wall 13A continuous with the one half cylinder portion 15A is more than the mating wall 16B on the side of the divided closed wall 13B continuous with the other half cylinder portion 15B. As shown in FIGS. 4 (A) and 4 (B), it is located outward, and as shown in FIG. 4 (C), it is inclined and easily displaced in the radial direction.
However, since the outward projecting portions 16A-1 and 16B-1 and the inward projecting portions 16A-2 and 16B-2 are provided to project, even if misalignment occurs, it is shown in FIGS. As described above, the inward protruding portion 16A-2 on the side of the divided closing wall 13A can be brought into contact with and opposed to the outward protruding portion 16B-1 on the side of the divided closing wall 13B.

  As described above, any of the matching walls 16A and 16B protruding inward and outward in the axial direction even if the half cylinder portions 15A and 15B are displaced in the axial direction and / or the radial direction when the adhesive tape T2 is wound. The parts of and face each other. Therefore, it can prevent that the slit 20 opens and the clearance gap which produces sound leakage arises in the part of the slit 20, and can maintain sound insulation performance.

5A and 5B show a modification of the grommet 1 of the first embodiment.
In the modification shown in FIG. 5 (A), the facing surfaces 16As and 16Bs of the mating walls 16A and 16B are used as a matte surface to make it difficult to slip.
In the modification shown in FIG. 5 (B), instead of using the facing surfaces 16As and 16Bs of the mating walls 16A and 16B as a matte surface, unevenness is provided, and the unevenness is fitted to each other so that the contact surface slips. Prevents more reliably.

FIG. 6 shows a grommet 1 (1-B) of the second embodiment.
As in the first embodiment, the grommet 1 of the second embodiment divides the closing wall 13 in the diametrical direction by the slit 20 and projects a half cylinder portion 15 (15A, 15B) at the center portion. Matching walls 30 and 31 are provided so as to project along the edges of the divided closed walls 13A and 13B that are respectively continuous with both side edges of the cylindrical portions 15A and 15B.

One mating wall 30 has an outer L-shape provided with a radially refracting portion 30b refracted in the radial direction at the tip of an outward projecting portion 30a projecting outward in the axial direction L from the divided edge. It is a mating wall. The other mating wall 31 is an inner L-shaped mating wall provided with a radially refracting portion 31b refracted in the radial direction at the tip of an inward projecting portion 31a projecting inward in the axial direction L.
The lengths of the radial refracting portions 30b and 31b are about 5 mm.

The radially bent portion 30b of the outer L-shaped mating wall 30 on the side of the divided closed wall 13A is assumed to overlap the outer surface of the divided closed wall 13B. Further, the radial refracting portion 31b of the inner L-shaped mating wall 31 on the side of the divided closed wall 13B is assumed to overlap the inner surface of the divided closed wall 13A.
In this manner, by overlapping the outer L-shaped mating wall 30 and the inner L-shaped mating wall 31, even if the divided edges on both sides sandwiching the slit 20 are displaced in the axial direction or / and the radial direction, In any part, they are opposed to each other, and the slit 20 is opened so that a large gap for sound leakage is not generated.
Since other configurations and operations are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.

FIG. 7 shows a modification of the second embodiment.
In the grommet, the slits 20a and 20b on both the left and right sides sandwiching the half cylinder portion 15 are opposite in the mating walls 30 and 31 on both sides, and as shown in the sectional view taken along the line DD in FIG. ) Is the reverse of the cross section.
That is, an outer L-shaped mating wall 30 is formed on the slit 20a side of the divided closed wall 13A, and an inner L-shaped mating wall 31 is formed on the slit 20b side. On the other hand, an inner L-shaped mating wall 31 is formed on the slit 20a side of the divided closed wall 13B, and an outer L-shaped mating wall 30 is formed on the slit 20b side.

  In this way, when the inner and outer overlapping surfaces are reversed on both sides, the slits 20a and 20b are restricted from opening each other, and the slit 20 is difficult to open and a gap where sound leakage occurs can be prevented from being opened.

FIG. 8A shows a grommet according to the third embodiment.
The grommet projects a mating wall 40 that protrudes outward in the axial direction from the edge of one divided closed wall 13A divided by the slit 20. An alignment provided with an axial protrusion 41a that protrudes outward and inward in the axial direction from the edge of the other dividing closed wall 13B, and a radial refraction part 41b that is refracted radially from the tip of the inward protrusion A wall 41 is projected. The outward projecting portions of the mating walls 40 and 41 are overlapped with each other, and the radial refracting portion 41b of the mating wall 41 is overlapped with the inner surface of the divided closed wall 13A.

When the mating walls 40 and 41 having the above-described shape are provided, even if both side edges sandwiching the slit 20 are displaced in the axial direction and / or the radial direction, the opposing surfaces of the mating walls 40 and 41 are brought into contact with each other. Thus, the opening of the slit 20 can be prevented and the sound insulation performance can be maintained.
Since other configurations and operational effects are the same as those of the grommet of the first embodiment, the same reference numerals are given and description thereof is omitted.

FIG. 8B shows a modification of the grommet according to the third embodiment.
The grommet projects a mating wall 40-A projecting inward in the axial direction from the edge of one of the divided closed walls 13A divided by the slit 20. An axial protrusion 41a-A that protrudes outward and inward in the axial direction from the edge of the other dividing wall 13B, and a radial refraction part 41b-A that is refracted in the radial direction from the tip of the outer protrusion. A mating wall 41-A provided with a projection is provided. The inward protruding portions of the mating walls 40-A and 41-A are overlapped with each other, and the radial direction refracting portion 41b-A of the mating wall 41-A is overlapped with the outer surface of the dividing closed wall 13A.

FIGS. 9A, 9B, and 9C show a grommet according to the fourth embodiment.
In the grommet 1 (1-D), the thickness t of the closing wall 13 is increased to about 4 mm. There is no provision of a mating wall projecting from the edge that sandwiches the slit 20 that divides the thick wall 13 into the inner and outer surfaces. Slits 50 and 51 refracted at the central portions of the slits 20a and 20b on both sides are provided, and an end wall divided by the slits 50 and 51 is provided with a mating wall that contacts each other.

  That is, the slits 50 and 51 include axial cuts 50a and 51a from the outer surface of the closed wall 13 to the center in the thickness direction, cuts 50b and 51b refracted in the horizontal direction at the center position in the thickness direction, and the horizontal direction. The cuts 50c and 51c are provided in the axial direction from the front end of the cut to the inner surface of the closing wall 13.

As shown in FIG. 9 (B), by providing the slit 50 on one side, the inner mating wall 50-1 in which the inner thick part of the edge of the dividing closed wall 13A is projected in the radial direction is provided, while the other The outer wall 50-2 projecting in the radial direction from the outer thick portion of the edge of the divided closed wall 13B protrudes, and the outer wall 50-2 and the inner wall 50-1 are made thicker. It is supposed to overlap in the direction. The outer mating wall 50-2 and the inner mating wall 50-1 are each about 5 mm in length and about half the thickness of the closing wall 13.
As shown in FIG. 9C, on the other hand, in the slit 51 on the other side, on the other hand, an outer mating wall is provided on the divided closing wall 13A, while an inner mating wall is provided on the divided closing wall 13B and overlapped in the thickness direction.

  In the grommet 1 of the fourth embodiment, even if the slit 50 is opened, the outer mating wall and the inner mating wall that protrude in the radial direction face each other and come into contact with each other. Can be prevented.

FIG. 10 shows a grommet according to the fifth embodiment.
In the grommet 1 (1-E), the split cylinder part 60 surrounding the wire harness insertion hole 14 provided in the center of the closing wall 13 is divided into 90% intervals, and each slit 61 is also provided at four intervals of 90 degrees. Provided. The alignment walls 63 and 64 protruding inward and outward in the axial direction similar to the first embodiment are provided along the edge of the divided closed wall sandwiching each of the slits 61a to 61d.
Instead of the mating wall of the first embodiment, any of the mating walls of the second embodiment, the third embodiment, or the fourth embodiment may be used.

DESCRIPTION OF SYMBOLS 1 Grommet 2 Wire harness 13 Closure wall 13A, 13B Divided closure wall 14 Wire harness insertion hole 15 (15A, 15B) Half cylinder part 18 Air layer 16A, 16B Matching wall T1, T2 Adhesive tape 20 (20a, 20b) Slit

Claims (7)

A small-diameter cylindrical portion that is molded from rubber or elastomer, and is inserted through the wire harness in close contact with each other, and a large-diameter cylindrical portion that expands from one end of the small-diameter cylindrical portion and is provided with an annular body-retaining recess on the outer peripheral surface; A closed wall continuous to the inner periphery of the large-diameter side end of the enlarged diameter cylindrical portion, a wire harness through hole provided in the center of the closed wall, a split cylinder portion and a wire projecting from the periphery of the wire harness through hole A grommet provided with a slit cut from the periphery of the harness through-hole toward the outer periphery,
Along each edge of the closed wall separated by the slit, a mating wall protruding in the axial direction and / or radial direction is provided oppositely, and the axial direction or / and radial position is provided on both side edges sandwiching the slit. A grommet configured such that any part of the mating wall comes into contact with and faces each other when a shift occurs.   2. The grommet according to claim 1, wherein the mating walls are mating walls that protrude outward and inward in the axial direction from end edges of the divided closed walls on both sides, and the mating walls are provided to face each other. . The mating wall is provided with an outer L-shaped mating wall protruding from one end edge divided by the slit and projecting outward in the axial direction and then refracted in the other radial direction. Is superimposed on the outer surface of the other closing wall, and
An inner L-shaped mating wall that protrudes inward in the axial direction from the other edge separated by the slit and then refracted in the one radial direction protrudes, and the refracting portion in the radial direction is The grommet according to claim 1, wherein the grommet is configured to overlap the inner surface of the closed wall.   The slits are provided in the diametrical direction, and each of the divided closed walls is provided with an outer L-shaped mating wall at one radial portion, and an inner L-shaped mating wall is provided at the other radius portion, and provided opposite to each other. The grommet according to claim 3, wherein the outer L-shaped mating wall and the inner L-shaped mating wall are reversely provided at the radial portions on both sides. The mating wall includes a mating wall that protrudes outward or inward in the axial direction from an edge of one closing wall divided by the slit, and an outer and inner side in the axial direction from the edge of the other closing wall. And a mating wall provided with a refracting portion in the radial direction from the inner or outer protruding end,
2. The grommet according to claim 1, wherein the protruding portions in the axial direction are overlapped with each other, and a radial refracting portion of the other mating wall is overlapped with an inner surface or an outer surface of the one divided edge.   While making the closed wall thick, refracting a slit provided in the closed wall, and making an outer thick wall protruding radially in the outer thick part of the edge of one closed wall divided by the slit, 2. The inner wall portion of the other closed wall at the end edge is formed as an inner mating wall projecting in the radial direction, and the outer mating wall and the inner mating wall are overlapped in the thickness direction of the closing wall. Grommet.   The grommet according to any one of claims 1 to 6, wherein a surface of the mating wall facing the other side is a matte surface or an uneven surface.

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