JP2545301Y2 - Grommet - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grommet, and more particularly to a grommet having a water-swellable elastic body in which a highly water-absorbent resin is blended with an elastic material such as an elastomer. The purpose is to improve soundproofing.

[0002]

2. Description of the Related Art Conventionally, various grommets have been provided which are used when a wire harness is inserted through an insertion hole provided in a vehicle panel or the like. FIG. 7 shows an example of a conventional grommet.

The grommet body 1 has a small-diameter cylindrical portion 1a for inserting and holding a wire harness 2, and the small-diameter cylindrical portion 1a.
And an enlarged diameter portion 1b through which the wire harness 2 is loosely inserted. A flange-like portion 1c is provided at the edge of the enlarged diameter portion 1b, and an annular groove 1d provided in the flange-like portion 1c is provided.
Into the edge of the insertion hole 3a provided in the panel 3,
Therefore, the grommet main body 1 is configured to be mounted and held on the panel 3.

Further, a filler 4 made of a liquid hardening material or the like is arranged in the enlarged diameter portion 1b to improve waterproofness and soundproofness.

[0005]

The filler 4 is fixed to the grommet body 1 by applying an adhesive to the outer peripheral portion 4a so as not to be peeled off after the grommet body 1 is attached to the panel. However, when the adhesive deteriorates, the filler 4 may be separated from the enlarged diameter portion 1b of the grommet body 1 and fall off. For example, when moisture enters a portion bonded by the adhesive due to rain, etc. The adhesive deteriorates due to moisture, and the adhesive strength is reduced.
There is a possibility that the filler 4 is peeled off.

Particularly, in an engine room or a trunk room of an automobile, when either the left side A or the right side B in the drawing of the panel 3 is set to the outside, a portion where moisture such as rain adheres a filler to the portion with an adhesive. It is easy to penetrate, and the filling material 4 is peeled off from the enlarged-diameter portion 1b due to the deterioration of the adhesive due to the above-mentioned moisture, and the waterproofness and soundproofness of the grommet are significantly reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems of the conventional grommet, and has an object to maintain soundproofness and waterproofness even when moisture enters. It was done as.

[0008]

SUMMARY OF THE INVENTION Therefore, according to the present invention, the inside of the panel or the like is sealed from the outside by mounting it between a through hole provided in a panel or the like and a wire harness inserted through the through hole. A grommet, in which a member made of a water-swellable elastic body is attached to a grommet body having elasticity, an outer peripheral portion of the wire harness is sealed by an elastic force of the member, and an engaging portion of the grommet body is inserted into the insertion hole. And a grommet characterized in that the grommet is sealed by pressing against an edge of the grommet.

Specifically, the member made of the water-swellable elastic body is a ring member housed in a ring-shaped space formed in the grommet body, and the ring member has a hole in the grommet body through which a wire harness passes. The inner peripheral surface of the portion is elastically brought into close contact with the outer peripheral portion of the wire harness, and the engaging portion of the grommet body is elastically pressed against the edge of the insertion hole,
It is preferable that the grommet body be expanded when moisture is absorbed, so that the grommet body is more firmly brought into close contact with or pressed against the outer peripheral portion of the wire harness and the edge of the through hole.

[0010] More specifically, the grommet body includes:
A first hole that tapers from the large-diameter opening to the small-diameter opening on the panel side, and a protrusion provided on the large-diameter opening side of the first hole and the small-diameter opening are in close contact with the outer peripheral portion of the wire harness; A tapered tubular portion having a large-diameter opening having a second hole portion through which the wire harness is loosely inserted in communication with the first hole portion; To form an engaging portion by forming a folded portion connected to the end face of the enlarged diameter portion by folding back in the insertion direction, and protruding the side surface portion of the enlarged diameter portion radially inward near the opening end of the second hole portion. Forming a reduced diameter part,
An annular groove is provided in the reduced diameter portion to fit the edge of the insertion hole, and a ring member is disposed as a ring-shaped space surrounded by the end surfaces, side surfaces, and the reduced diameter portion of the folded portion and the enlarged diameter portion. preferable.

Alternatively, the grommet main body includes a small-diameter cylindrical portion having a first hole portion closely contacting an outer peripheral portion of the wire harness, and a second hole portion communicating with the first hole portion to loosely insert the wire harness. And an enlarged diameter portion provided in the second hole portion.
A cylindrical portion having a third through-hole that is in close contact with the outer peripheral portion of the wire harness is provided, and a connecting portion extending radially outward from an outer peripheral portion of an opening end of the cylindrical portion on the small-diameter cylindrical portion side is formed as a second portion. It is preferable that the ring member is connected to the inner peripheral surface of the hole, and the ring member is arranged as a ring-shaped space surrounded by the outer peripheral portion of the cylindrical portion, the connecting portion, and the inner peripheral surface of the second hole.

The grommet main body includes a small-diameter cylindrical portion provided with a first hole portion which is in close contact with the outer peripheral portion of the wire harness, and a second hole portion which communicates with the first hole portion and through which the wire harness is loosely inserted. A member provided with an engaging portion on an opening end side of an outer peripheral portion of the large-diameter portion, and the member made of the water-swellable elastic body is a ring-shaped member arranged in the second hole portion. The inner peripheral surface of the ring member elastically and directly adheres to the outer peripheral portion of the wire harness, and the outer peripheral surface of the ring member elastically presses the engaging portion of the grommet body against the edge of the insertion hole. Good.

The water-swellable elastic material is, for example, an elastomer or the like, that is, natural rubber, styrene-butadiene (SB
R), butyl rubber, EPDM, chloroprene, NBR,
For IIR, SIS, urethane resin, acrylic resin, silicone rubber, EVA, vinyl chloride resin, etc., vinyl acetate / acrylate copolymer ken compound, isobutylene / maleic acid copolymer crosslinked product, polyethylene oxide type etc. It contains a water-absorbing resin.

[0014] The ring-shaped member may be provided with a slit by cutting out a part in the circumferential direction.

[0015]

In the grommet according to the present invention, since the grommet has the above-described structure, the hole of the grommet main body or the water-swellable elastic body is normally used due to the elastic force of the water-swellable elastic member attached to the grommet main body. The body member itself is sealed by closely contacting the outer peripheral portion of the wire harness, and the engaging portion of the grommet body is elastically pressed against the edge of the insertion hole to seal. Further, when moisture enters the grommet according to the present invention, the moisture is absorbed by the member made of the water-swellable elastic body and expanded, so that the seal and the engaging portion with respect to the outer peripheral portion of the wire harness are inserted into the insertion hole. The pressing force for pressing the plate is further increased.

For example, as described above, the grommet body is provided with the tapered tubular portion, and the enlarged diameter portion provided with the second hole portion through which the wire harness is loosely inserted in communication with the tapered tubular portion. When the end of the large-diameter opening side is folded back in the insertion direction of the wire harness to form a folded portion connected to the end face of the enlarged diameter portion, normally, the end face of the folded portion and the enlarged diameter portion, Due to the elastic force of a ring member composed of a water-swellable elastic body disposed in a ring-shaped space formed from a portion surrounded by the side surface portion and the reduced diameter portion, the small-diameter opening portion of the tapered tubular portion and the large-diameter opening side The protrusion provided on the inner peripheral surface elastically adheres to the outer peripheral portion of the wire harness, and a reduced diameter portion provided with an annular groove in which the edge of the insertion hole provided in the panel is fitted elastically. Is pressed.

When moisture enters the portion of the panel where the grommet is attached, the moisture is absorbed and expanded by the ring member made of the water-swellable elastic body, and the expansion causes the protrusion and the small-diameter opening through the folded portion. Is more strongly adhered to the outer peripheral portion of the wire harness, and the reduced diameter portion is more strongly pressed against the edge of the insertion hole.

Further, as described above, when the slit portion is provided in the ring-shaped member, the wire harness can be easily arranged on the inner peripheral side from the slit portion.

[0019]

Next, an embodiment of the present invention will be described in detail based on an embodiment shown in the drawings. In the first embodiment of the present invention shown in FIG. 1, the grommet main body 11 is made of EPDM, and a tapered cylindrical portion 12 that tapers from the panel 3 side to the inside A of the panel 3;
2 is provided with an enlarged diameter portion 13 connected to the panel 3 side. The tapered cylindrical portion 12 has a tapered first hole 12a through which the wire harness 2 is inserted, and a protrusion 12d provided on the small-diameter opening 12b and the large-diameter opening 12c of the first hole 12a.
Are in close contact with the outer peripheral portion of the wire harness 2.

The enlarged diameter portion 13 communicates with the first hole portion 12a of the tapered tubular portion 12 on the inner side A of the panel 3 and has a second hole portion 13a into which the wire harness 2 is loosely inserted. The large-diameter opening 12c of the tapered cylindrical portion 12 is located near the center in the thickness direction of the large-diameter portion 13, and the end on the large-diameter opening 12c side is folded in the insertion direction of the wire harness 2 to form a folded portion 12e. Is formed, and the folded portion 12e is connected to the end face 13b of the enlarged diameter portion 13. Therefore, the folded portion 12e and the outer peripheral portion of the tapered cylindrical portion 12 form a V-shaped portion having a predetermined angle.

At the opening end of the second hole 13a of the enlarged diameter portion 13, a side portion 13c of the enlarged diameter portion 13 is projected radially inward to form a reduced diameter portion 13d, and a cross section is formed at the reduced diameter portion 13d. A substantially U-shaped annular groove 13e is provided. In addition, the annular groove 13e
The wall surface 13f that comes into contact with the surface on the inner side A of the panel 3 is formed in a bellows shape.

In the grommet main body 11 of the first embodiment, the folded portion 12e,
The end surface 13b, the side surface portion 13c, and the reduced diameter portion 13d form a ring-shaped space 13g having a substantially rectangular cross section.

A ring member 14 made of a water-swellable elastic body having a shape as shown in detail in FIG. 2 and having a width, thickness, and outer diameter adapted to the ring-shaped space 13g is provided in the ring-shaped space 13g. Has been arranged. The water-swellable elastic body is an elastic material that expands by absorbing moisture, and in the first embodiment,
EVA as a water-swellable elastic body forming the ring member 14
A resin blended with a saponified vinyl acetate / acrylate copolymer is used. Also, the ring member 1
Reference numeral 4 denotes a slit 14a formed by cutting out one stroke in the circumferential direction.

With the grommet according to the first embodiment,
When the wire harness 2 is inserted through the panel 3,
Perform as follows. First, the wire harness 2 is arranged from the outer peripheral surface 14b to the inner peripheral surface 14c via the slit portion 14a of the ring member 14. Next, the grommet body 11
Is elastically pushed out, and the wire harness 2 is connected to the first hole 1.
2a and the second hole 13a. Thereafter, the ring member 14 is elastically pushed and spread to be disposed in the ring-shaped space 13g of the grommet main body 11 from the opening end side of the second hole portion 13a, and then the edge of the insertion hole 3a of the panel 3 is reduced in diameter by the reduced diameter portion 13d.
Is fitted into the annular groove 13e provided in.

In the first embodiment, the portion of the small-diameter opening 12b of the tapered cylindrical portion 12 and the projection 12d are brought into close contact with the outer peripheral portion of the wire harness 2 by the elastic force of the ring member 14, and the insertion hole 3a of the panel 3 is closed. The edge is fitted into the fitting groove 13e of the grommet body 1, the wall 13f is pressed against the panel 3 by the elastic force of the ring member 14, and the bottom surface of the fitting groove 13e is pressed against the edge of the insertion hole 3a. Is done. Therefore, the outer peripheral portion of the wire harness 2, the grommet main body 1, and the gap between the insertion hole 3a of the panel 3 and the grommet main body 1 can be sealed, and a waterproof and soundproof effect can be obtained.

In the first embodiment, if the panel 3
When water tries to enter the inner side A from the outer side B of
The ring member 14 expands by absorbing the moisture. Therefore, as shown in FIG. 3, the ring-shaped member 14 has a folded portion 13b closely contacting the outer peripheral portion of the tapered tubular portion 12, and a portion of the small-diameter opening 12a of the first hole portion 12a and the projection through the folded portion 13b. The part 12d is more firmly adhered to the outer peripheral part of the wire harness 2.

Also, due to the expansion of the ring member 14,
The wall surface 13f of the annular groove 13e is more firmly pressed against the surface on the inner side A of the panel 3, and the bottom of the annular groove 13e is more firmly pressed against the edge of the insertion hole 3a.

As described above, in the first embodiment, since the ring member 14 made of a water-swellable elastic body is attached to the grommet body 11, the grommet is normally attached to the wire harness 2 and the panel 3 by the elastic force of the ring member 14. Body 1
1 and thus a waterproof and soundproof effect can be obtained. When moisture tries to enter the inside A from the outside B of the panel 3, the moisture is added to the ring member 14 in addition to the normal sealing force due to the elastic force of the ring member 14.
By absorbing and expanding, the wire harness 2 and the grommet main body 11 and between the grommet main body 11 and the panel 3 are pressed more firmly, so that the waterproof effect can be improved.

Further, in the first embodiment, while the grommet body 11 is formed from EPDM as described above, the ring member 14 is formed by blending a saponified vinyl acetate / acrylate copolymer with EVA resin. ing. Accordingly, the grommet body 11 and the ring member 14 have different densities, and sound is difficult to be transmitted at the contact surface between the grommet body 11 and the ring member 14, which can also provide a soundproof effect.

In the second embodiment of the present invention shown in FIG. 4, the grommet main body 21 includes a small-diameter cylindrical portion 21b having a first hole 21a closely attached to the outer peripheral portion of the wire harness 2, and the first hole 21a. The enlarged diameter portion 21d provided with the second hole portion 21c through which the wire harness 2 is loosely inserted is provided continuously.

On the opening end side of the second hole 21c, a flange-like portion 21e is formed to protrude the outer peripheral portion radially outward to form an engaging portion, and the insertion hole of the panel 3 is formed in the flange-like portion 21e. A fitting groove 21f for fitting the edge of 3a is formed in the entire circumferential direction. The cylindrical portion 2 is provided in the second hole 21c.
2 are provided. Third hole portion 22 provided in this cylindrical portion 22
a is in close contact with the outer peripheral portion of the wire harness 2 and has a small-diameter cylindrical portion 21b.
Connecting portion 2 extending in the circumferential direction on the outer peripheral portion of the side open end 22b
It is connected to the peripheral surface of the second hole 21c via 2c.

In the second embodiment, the wire harness 2 has the first hole 21a and the second hole 21a.
The grommet body 21 is penetrated through the hole 21c and the third hole 22a.

A portion surrounded by the outer peripheral portion of the cylindrical portion 22, the connecting portion 22c and the peripheral surface of the second hole portion 21c forms a ring-shaped space 23, and the portion of the ring-shaped space 23 forms the second hole portion 21c. An annular projection 21g for engagement is provided on the peripheral surface of the rim. A ring member 24 made of a water-swellable elastic body is disposed in the ring-shaped space 23 as in the first embodiment. The outer periphery of the ring member 24 is provided with an annular groove 24a for fitting the above-mentioned annular projection 21g, thereby preventing the ring member 24 from falling off.

In the second embodiment, since the above configuration is adopted, the inner peripheral surface 24b of the ring member 24 is normally used.
The third hole portion 22a is brought into close contact with the outer peripheral portion of the wire harness by the force of elastically shrinking, while the outer peripheral surface 24c
Presses and spreads the flange portion 21e outwardly by a force to expand elastically, so that the annular groove 21f is elastically pressed against the edge of the insertion hole 3a of the panel 3.

When moisture tries to enter the inside A from the outside B of the panel 3, the moisture is absorbed by the ring member 24, and the ring member 24 expands. This ring member 24
Due to the expansion, the third hole portion 22a is more firmly adhered to the outer peripheral portion of the wire harness 2, and the edge of the insertion hole 3a of the panel 3 is more firmly held in the annular groove 21f to improve the waterproof effect. be able to.

In the third embodiment of the present invention shown in FIG. 5, the grommet main body 26 includes a small-diameter cylindrical portion 26b provided with a first hole 26a that is in close contact with the outer peripheral portion of the wire harness 2, and a first hole 26a. And an enlarged diameter portion 26d provided with a second hole portion 26c through which the wire harness 2 is loosely inserted. Further, a flange-like portion 26e constituting an engaging portion is provided at an end edge of the enlarged diameter portion 26d, and the annular groove 2 provided in the flange-like portion 26e is provided.
The edge of the insertion hole 3a provided in the panel 3 is fitted into 6f, and thus the grommet main body 1 is held on the panel 3.

A ring member 27 made of a water-swellable elastic body is disposed near the opening end of the second hole 26c.
In the ring member 27, the inner peripheral surface 27a is in close contact with the outer peripheral portion of the wire harness 2, and the outer peripheral portion 27b is in close contact with the second hole portion 26c. Further, an annular projection 27c is provided on the outer peripheral portion 27b, and the annular projection 27c is formed in the second hole 26c.
The ring member 27 is fitted in an annular groove 26g provided near the opening end of the second hole 26c to prevent the ring member 27 from peeling off from the second hole 26c.

In the third embodiment, similarly to the first and second embodiments, at normal times, the ring member 27 has the first hole elastically adhered to the outer peripheral portion of the wire harness 2.
The annular groove 26f is pressed against the edge of the insertion hole 3a by elastically pushing and expanding the flange-like portion 26e of the grommet main body 26.

When moisture enters the inside A from the outside B of the panel 3, the moisture is absorbed by the ring member 27 and swells, so that the inner peripheral surface 27a of the ring member 27 is expanded.
The outer peripheral portion of the wire harness 2 and the annular groove 26f of the grommet main body 26 and the edge portion of the insertion hole 3a are further brought into close contact with each other to improve waterproofness.

The present invention is not limited to the above embodiment, and various modifications are possible. For example, the water-swellable elastic body forming the ring member is the EVA described above.
The resin is not limited to a mixture of a saponified vinyl acetate / acrylate copolymer and is not limited to an elastomer or the like, that is, natural rubber, styrene butadiene (SB
R), butyl rubber, EPDM, chloroprene, NBR,
Even if a compound obtained by blending a highly water-absorbing resin such as a crosslinked product of isobrylene / maleic acid copolymer or polyethylene oxide with IIR, SIS, urethane resin, acrylic resin, silicone rubber, EVA, vinyl chloride resin, etc. is used. Good.

The material of the grommet body is also E
The present invention is not limited to the PDM, and other suitable elastic materials may be used.

Further, the shapes of the grommet main body and the ring member are not limited to those of the above-described embodiment. The outer periphery of the wire harness is sealed by the elasticity of the ring member, and the grommet main body and the panel insertion hole are formed. It can be changed as appropriate as long as it is configured to strengthen the engagement of. For example, as shown in FIG. 6, in the third embodiment, the ring member 27 'is provided with the second hole portion 26c of the enlarged diameter portion 26d.
May be filled entirely. Further, the ring member may not be provided with a slit portion. Further, the ring-shaped member may be configured to be divided into a plurality in the circumferential direction,
The ring member may be located on either the inside or the outside of the panel.

[0043]

As is apparent from the above description, in the grommet according to the present invention, a part of the grommet body or the inner peripheral surface of the ring member itself is formed by the elastic force of the ring member made of the water-swellable elastic body. In order to seal the outer peripheral portion of the wire harness by elastically contacting the outer peripheral portion thereof and to seal the outer peripheral portion of the wire harness by pressing an engaging portion that engages with the insertion hole provided on the panel against an edge portion of the insertion hole, A waterproof effect and a soundproof effect can be obtained by the elastic force of the ring member itself. Further, when moisture tries to invade from the outside to the inside of the panel, the ring member absorbs the moisture and expands, so that the part of the grommet body or the ring member itself is more firmly attached to the outer periphery of the wire harness. And the engaging portion can be more firmly pressed against the edge of the insertion hole. Therefore, the grommet according to the present invention can obtain good waterproofness and soundproofness even when used in a place easily exposed to moisture such as rain, such as a trunk room and an engine room of an automobile.

In the grommet according to the present invention, when the density of the material forming the grommet body and the density of the water-swellable elastic body constituting the ring member are made different, sound is hardly transmitted at this portion. Therefore, soundproofing can be further improved.

Further, in the grommet according to the present invention, only the ring member is formed from a water-swellable elastic body, and the grommet body itself can be formed from relatively inexpensive EPDM or the like, so that the cost can be reduced. It has various advantages such as possible.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing a water-swellable elastomer.

FIG. 3 is a cross-sectional view showing a case where moisture has entered the inside of the panel.

FIG. 4 is a sectional view showing a second embodiment of the present invention.

FIG. 5 is a sectional view showing a third embodiment of the present invention.

FIG. 6 is a sectional view showing a modification of the third embodiment.

FIG. 7 is a sectional view showing an example of a conventional grommet.

[Explanation of symbols]

 Reference Signs List 2 wire harness 3 panel 3a insertion hole 11, 21, 26, grommet body 12 tapered cylindrical portion 14, 24, 27 ring member 14a slit portion 12a, 21a, 26a first hole portion 13a, 21c, 26c second hole portion 22 Cylindrical part 22a Third hole part 22c Connection part

Claims (2)

(57) [Scope of request for utility model registration] 1. A grommet which is mounted between an insertion hole provided in a panel or the like and a wire harness inserted through the insertion hole to seal the inside of the panel or the like from the outside, wherein the main body of the grommet is A first hole that tapers from the large-diameter opening to the small-diameter opening on the panel side, and the projection provided on the large-diameter opening side of the first hole and the small-diameter opening are in close contact with the outer peripheral portion of the wire harness. A tapered tubular portion, and a large-diameter portion provided with a second hole portion through which the wire harness is loosely inserted in communication with the first hole portion, and the large-diameter opening side end of the tapered tubular portion is provided. Forming a folded portion connected to the end surface of the enlarged diameter portion by folding back in the insertion direction of the wire harness, and projecting the side surface portion of the enlarged diameter portion radially inward near the opening end of the second hole portion to engage the engaging portion; Forming a reduced diameter portion, and fitting the edge of the panel insertion hole into the reduced diameter portion. An annular groove is provided, and a portion surrounded by the end face, the side surface, and the reduced diameter portion of the folded portion and the enlarged diameter portion is a ring-shaped space, and a ring member made of a water-swellable elastic body is accommodated in the ring-shaped space. The inner peripheral surface of the ring member is pressed against the folded portion to elastically contact the folded portion with the outer peripheral portion of the wire harness, and the engaging portion is elastically fitted to the edge of the insertion hole of the panel. The grommet is characterized in that the grommet is configured to be pressed against water, expanded when absorbing moisture, and pressed with a stronger force to seal with water. 2. A grommet which is mounted between an insertion hole provided in a panel or the like and a wire harness inserted through the insertion hole to seal the inside of the panel or the like from the outside, wherein the main body of the grommet is A small-diameter cylindrical portion provided with a first hole portion in close contact with the outer peripheral portion of the wire harness; and a large-diameter portion provided with a second hole portion in communication with the first hole portion to loosely insert the wire harness. A cylindrical portion provided with a third through hole that is in close contact with the outer peripheral portion of the wire harness is provided in the second hole portion in a folded manner, and radially outward from the outer peripheral portion of the opening end of the cylindrical portion on the small-diameter cylindrical portion side. Connecting the extending connecting portion to the inner peripheral surface of the second hole portion,
An outer peripheral portion of the cylindrical portion, a portion surrounded by an inner peripheral surface of the connection portion and the second hole portion is defined as a ring-shaped space, and the ring-shaped space includes:
A ring member made of a water-swellable elastic body is accommodated, and the inner peripheral surface of the ring member is pressed against the folded cylindrical portion to elastically adhere the cylindrical portion to the outer peripheral portion of the wire harness, A grommet characterized in that the engagement portion is elastically pressed against the edge of the insertion hole, expands when absorbing moisture, and is pressed with a stronger force to seal the grommet.