JPH10285754A - Sound-insulating grommet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise coming from an engine room into a cabin from a grommet attaching part. SOLUTION: A sound-insulating member 12, consisting of a sound absorbing member 18 which is pushed into the expanded diameter cylinder 16 of a grommet main part 11 from an opening side closes the opening, and a sound- insulating surface skin 19 attached to the tip surface of the sound-absorbing member 18 is provided. A wiring harness is inserted through the central holes of sound absorbing member 18 and the sound insulating surface skin 19 to attach the grommet to the wiring harness, and the sound insulating surface skin 19 is attached so as to be superposed upon a sound insulator 3 attached to the cabin side of a panel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grommet for sealing which is attached to a wire harness which is routed through a through hole provided in a partition wall between an engine room and a vehicle compartment of an automobile, and which is attached to the through hole. To reduce the noise transmitted from the vehicle to the indoor side.

[0002]

2. Description of the Related Art In recent years, it has been strongly demanded in automobiles to maintain a quiet interior of a vehicle from the viewpoint of enhancing comfort, in which case the noise from the loudest engine room into the vehicle compartment is cut off. It is necessary to do. Therefore, conventionally, as shown in FIG. 8, a sound absorbing material 2 made of urethane or the like is attached to a panel (partition) 1 that partitions an engine room (X) and a vehicle room (Y) on the vehicle room side inner surface. Further, a sound insulating material 3 made of leather or the like is attached to the indoor side surface of the silencer material 2.

[0003]

As described above, the silencer including the sound absorbing material 2 and the sound insulating material 3 is attached to the panel 1 so that the noise of the engine room (X) is prevented from being transmitted to the vehicle room (Y). Panel 1
It is necessary to provide a through-hole 4 to route the wiring harness W / H from the engine room side to the indoor side, and attach a grommet 5 attached to the wiring harness W / H to the through-hole 4. However, there is a problem that noise in the engine room is easily transmitted from the through hole 4 to the room.

That is, in order to attach the grommet 5 to the through hole 4, as shown in FIG. 9A, the grommet 5 is passed through the wire harness W / H from the engine room (X) side, and As shown in FIG. 9, once inserted into the cabin (Y), the grommet 5 is returned to the engine room (X) as shown in FIG.
It is necessary to lock the locking groove 5b formed on the outer periphery of the through hole 4 at the peripheral edge of the through hole 4.

In order to temporarily insert the enlarged diameter portion 5a of the grommet 5 into the room (Y) as described above, the silencer including the sound absorbing material 2 and the sound insulating material 3 attached to the indoor side of the panel 1 is provided with a diameter expansion of the grommet 5. So as not to bite into the part 5a
It is necessary to keep a large circular space. That is, in FIG. 8, the relationship between the inner diameter A of the through hole 4, the outer diameter B of the enlarged diameter portion 5 a, and the inner diameter C of the circular space of the sound insulating material 3 is A <
B <C. As a result, in the mounting portion of the grommet 5, the sound absorbing material 2 and the sound insulating material 3 allow the engine room side noise to pass through the periphery of the through hole 4 of the panel 1 and the thin portion 5c of the grommet 5, as indicated by the arrow in FIG. And transmitted to the inside of the room, and effective sound insulation could not be achieved.

The present invention has been made in view of the above-described problem, and has as its object to reduce transmission of noise from an engine room to a vehicle interior through a grommet mounting portion.

[0007]

In order to solve the above problems, according to the present invention, a sound absorbing material and a sound insulating material are attached to a vehicle compartment side inner surface of a panel for separating an engine room and a vehicle room of a vehicle. A grommet to be mounted in a through hole of a wire harness provided in the panel, a small-diameter tube portion through which the wire harness is inserted in close contact, and a large-diameter tube portion expanding from one end of the small-diameter tube portion. A grommet body having a locking groove on the outer peripheral surface of the enlarged diameter cylindrical portion; a sound absorbing member that is fitted into the enlarged diameter cylindrical portion of the grommet body from an opening side and closes the opening; A sound-insulating member comprising a sound-insulating skin attached to the distal end surface of the sound-absorbing member protruding from the cylindrical portion. The grommet is attached by inserting a wire harness into a central hole of the sound-absorbing member and the sound-insulating skin of the sound-insulating member. Sound insulation skin The offering sound insulation grommet, characterized in that it is configured to mount superposing a sound insulator that is attached to the indoor side of the panel.

As described above, since the sound insulating member is attached to the grommet main body, first, the small diameter portion of the sound absorbing member of the sound insulating member is fitted inside the enlarged diameter cylindrical portion of the grommet main body. Transmission of noise from the thin portion on the bottom surface can be reduced. Further, the large-diameter portion of the sound absorbing member can reduce the space facing the through hole of the sound absorbing member attached to the inner surface of the panel. Further, since the sound-insulating skin portion is overlapped with the sound-insulating material arranged on the inner surface side of the panel, the space can be shielded. Therefore, transmission of noise from the engine room from the portion of the panel through hole to the vehicle interior can be effectively reduced.

The sound-absorbing member is made of a foam material such as urethane and has a small-diameter portion that fits inside the enlarged-diameter tube portion of the grommet body, and a large-diameter portion that closes the opening at the end of the enlarged-diameter tube portion. The sheet-like sound insulation skin portion made of vinyl chloride or the like is attached to the surface of the portion with its outer peripheral portion protruding, and the sound absorbing material and the sound insulation skin material are provided with an axial slit, and the slit is opened to open the wire. A sound insulation member is attached to the harness from the side (Claim 2).

[0010]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, a grommet 10 of the present invention includes a grommet body 11 integrally molded from rubber or an elastomer, and a grommet body 1.
1 and a sound insulation member 12 attached to the sound insulation member 12.

The grommet main body 11 has the same shape as that of the prior art, and includes a small-diameter tube portion 15 through which the wire harness W / H is inserted in close contact, and a large-diameter tube portion 16 expanding from one end of the small-diameter tube portion 15. The conical bottom surface 16a of the enlarged diameter cylindrical portion 16 is made thinner and the peripheral wall portion 16b is made thicker, and a locking groove 17 is annularly formed on the outer peripheral surface of the thicker peripheral wall portion 16b. The shape of the grommet main body 11 is not limited to the above-mentioned shape, and can be applied to the grommet main body 11 having a shape having the enlarged-diameter cylindrical portion 16 having an open end.

The sound insulating member 12 has a sound absorbing portion 18 made of urethane having a two-stage annular shape and a ring-shaped sheet made of vinyl chloride adhered to the surface of the large diameter portion 18a of the sound absorbing portion 18. It is composed of a skin portion 19. The small-diameter portion 18b inserted into the large-diameter tube portion 16 of the grommet body 11 from the opening side and fitted therein, and the large-diameter portion 18b abutting on the distal end surface of the large-diameter portion 16 to close the opening. Consists of The center hole 18 between the small diameter portion 18b and the large diameter portion 18b
e and 18f are wire harness insertion holes. Note that the sound absorbing material 18 is not limited to a foam material such as urethane, and may have any sound absorbing properties. In addition, the skin portion 19 for sound insulation is not limited to the vinyl chloride sheet, and may be any material having excellent flexibility and sound insulation.

The small diameter portion 1 of the sound absorbing portion 18 of the sound insulating member 12
The thickness t1 of the grommet main body 11 is equal to the thickness t1 of the grommet main body 11.
The thickness t2 of the large-diameter portion 18b corresponds to the depth of the panel 1 with the grommet 10 attached to the panel through hole 4.
The outer diameter of the sound insulating material 3 is set larger than the inner diameter of the hole of the sound insulating material 3 so that the sound insulating material 3 attached via the sound absorbing material 2 and the skin 19 for sound insulating overlap.

Further, slits 18c, 19c which are continuous in the axial direction are formed in the sound absorbing portion 18 and the sound insulating skin portion 19 of the sound insulating member 12 so as to form a wire harness W.
/ H from the side perpendicular to the axis. A central hole 19a for inserting the wire harness of the sound insulating skin portion 19 is formed by cutting and raising, and the cut and raised skin is used as a wire harness fixing tongue piece 19b.

The grommet 10 including the grommet body 11 and the sound insulating member 12 is connected to a wire harness W /
H, as shown in FIG. 3, pushes the small-diameter cylindrical portion 15 of the grommet main body 11 using a diameter-expanding machine (not shown) and inserts it. After insertion, the wire harness W
/ H around the tape 20 and the grommet body 1
1 and the wire harness W / H are fixed. After that, the sound insulating member 12 is inserted into the slit 18 in front of the opening side of the large-diameter tube portion 16.
c and 19c are spread and assembled to the wire harness W / H from the side, and the wire harness W / H is passed through the center holes 18e, 18f and 19a. After assembling, the sound insulating member 12 is moved toward the grommet main body 1 and the small diameter portion 18b of the sound absorbing portion 18 is moved.
Is pushed into the enlarged-diameter tube portion 16 to be fitted therein.

In this state, the opening of the large-diameter cylindrical portion 16 of the grommet body 11 is closed by the large-diameter portion 18a of the sound-absorbing portion of the sound-insulating member 12, and a sound-insulating skin portion 19 is provided on the protruding distal end surface of the large-diameter portion 18a. positioned. Next, the tape 21 is wound around the outer peripheral surface of the wire harness W / H together with the fixing tongue piece 19b of the sound insulating skin portion 19 to fix the sound insulating member 12 to the wire harness W / H.

With the grommet 10 previously attached to the wire harness W / H as described above, the engine room (X) and the vehicle room (Y) are partitioned as shown in FIGS. 4 (A) to 4 (C). The grommet 10 is attached to the through hole 4 of the panel 1 through the wire harness W / H. As in the prior art, a sound absorbing material 2 made of urethane and a sound insulating material 3 made of vinyl chloride are attached to the interior of the panel 1 as in the prior art. Material 3.

First, as shown in FIG. 4A, the grommet 10 is inserted from the engine room (X) into the vehicle room (Y) through the through hole 4 of the panel 1, and as shown in FIG. Then, the entire grommet 10 including the sound insulating member 12 on the distal end side is passed through the interior of the passenger compartment (Y). At this time, since the outer diameter of the sound insulating skin portion 19 is set to be larger than the inner diameter of the hole of the sound insulating material 3, the sound insulating skin portion 19 overlaps the sound insulating material 3 and deforms the sound insulating material 3 toward the indoor side. Let it.

Then, as shown in FIG. 4 (C), the wire harness W / H is pulled back to the engine room (X) side, and the locking groove 17 of the grommet main body 11 is locked to the peripheral edge of the through hole 4. The grommet 10 is fixed to the panel 1.

In this state, the sound insulating skin portion 19 is
And a large-diameter portion 18a of the sound absorbing portion is positioned inside the sound absorbing member 19 to keep the sound insulating skin portion 19 and the sound insulating material 3 in contact with each other.

When the grommet 10 is mounted in the through hole 4 of the panel 1 as described above, the hole area of the sound absorbing material 2 mounted on the indoor side of the panel 1 is reduced by the large diameter portion 18a of the sound insulating member 12. Further, the holes of the sound insulating material 3 are completely closed by the sound insulating skin portion 19. Further, the small-diameter portion 18b is fitted inside the enlarged-diameter tube portion 16 opened in the grommet body 11, and absorbs sound that enters from the thin bottom surface 16a. Therefore, the noise of the engine room (X) that enters the cabin (Y) from the grommet mounting portion of the panel through hole can be effectively reduced.

FIGS. 5A and 5B show a modified example of the first embodiment. When the grommet 10 is inserted into the vehicle interior (Y), the sound insulating skin portion 19 at the distal end extends beyond the sound insulating material 3. In this case, as shown in FIG. 5 (B), the sound insulating skin portion 19 of the grommet 10 includes the sound insulating material 3.
Will be located on the indoor side surface. Also in this case, similarly to FIG. 4C, transmission of noise to the vehicle interior can be effectively reduced.

FIGS. 6 and 7 show a second embodiment in which a hose 30 made of a thin tube is passed through the grommet 10 together with a wire harness W / H. Has been established,
A hose through hole 18 continuous with slits 18c and 19c is formed in the sound absorbing portion 18 and the sound insulating skin portion 19 of the sound insulating member 12.
g.

As described above, even when the hose 30 is passed through the grommet 10 together with the wire harness W / H, the sound insulating member 12 can be attached to the grommet main body 11 to transmit noise from the engine room side to the vehicle interior. Can be reduced.

[0025]

As is apparent from the above description, according to the present invention, a sound insulating member in which a sound absorbing material made of urethane or the like and a sheet-shaped sound insulating skin material made of vinyl chloride are integrated with a grommet body. Therefore, transmission of noise from the grommet mounting space of the sound absorbing material and the sound insulating material attached to the inner surface of the panel on the vehicle interior side can be reduced.

In particular, since the sound insulating member is provided separately from the grommet main body, it is only necessary to attach the sound insulating member to a conventionally used grommet, which has an advantage that it can be easily implemented. In addition, the grommet body has a simple structure, and the sound insulation member has a simple shape in which a sound absorbing material made of a ring-shaped urethane or the like and a vinyl chloride sheet are bonded together. is there.

[Brief description of the drawings]

FIG. 1 shows a grommet according to a first embodiment of the present invention,
(A) is a perspective view, (B) is a sectional view.

FIGS. 2A and 2B are perspective views showing a sound insulating member used for the grommet, and FIG. 2B is an enlarged sectional view.

FIG. 3 is a cross-sectional view showing a state where a wire harness is attached to the grommet.

FIGS. 4A, 4B, and 4C are cross-sectional views showing steps of attaching the grommet to a panel through-hole.

FIGS. 5A and 5B are cross-sectional views showing a step of attaching a grommet showing a modification of the first embodiment to a panel through-hole.

FIG. 6 is a perspective view showing a grommet according to a second embodiment of the present invention.

FIG. 7 is a perspective view of a sound insulating member according to the second embodiment.

FIG. 8 is a cross-sectional view showing a state where a conventional grommet is attached to a panel through hole.

FIGS. 9A, 9B, and 9C are cross-sectional views showing a process of attaching a conventional grommet to a panel through hole.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Panel 2 Sound absorbing material 3 Sound insulating material 4 Through hole 10 Grommet 11 Grommet main body 12 Sound insulating member 15 Small diameter cylindrical part 16 Large diameter cylindrical part 17 Engagement groove 18 Sound absorbing part 18a Large diameter part 18b Small diameter part 18e, 18f Center hole 18c Slit 19 Sound insulation skin 19a Center hole 19c Slit W / H Wire harness X Engine room Y Cab

Claims (2)

[Claims] 1. A grommet which has a sound absorbing material and a sound insulating material attached to a vehicle compartment side inner surface of a panel separating an engine room and a vehicle compartment of an automobile, and which is mounted in a through hole of a wire harness provided in the panel. A grommet having a small-diameter tube portion through which a wire harness is inserted in close contact, and a large-diameter tube portion expanding from one end of the small-diameter tube portion, and having a locking groove on an outer peripheral surface of the large-diameter tube portion A main body, a sound absorbing member that fits inside the enlarged-diameter tube portion of the grommet main body from the opening side and closes the opening, and a sound-insulating skin portion attached to a distal end surface of the sound-absorbing member protruding from the enlarged diameter tube portion. A wire harness is inserted through a central hole of the sound absorbing member and the sound insulating skin portion of the sound insulating member, and the sound insulating skin portion of the grommet is overlapped with the sound insulating material mounted on the indoor side of the panel. Take Sound insulation grommet, characterized in that it is configured to apply. 2. The sound absorbing member is made of a foam material such as urethane, and has a small-diameter portion that fits inside the enlarged-diameter tube portion of the grommet main body.
A large-diameter portion that closes the opening of the distal end of the enlarged-diameter cylindrical portion, and the sheet-like sound-insulating skin made of vinyl chloride or the like is attached to the surface of the large-diameter portion so that the outer peripheral portion protrudes, and the sound absorption is performed. The sound insulating grommet according to claim 1, wherein an axial slit is provided in the material and the sound insulating skin material, and the slit is opened to attach a sound insulating member to the wire harness from the side.