JP2011259643A - Grommet for wiring harness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a grommet of two-body objects, where the resin inner is assembled to a grommet body, to be inserted even an insertion direction of the grommet to a through hole is at a slant.SOLUTION: A grommet for a wiring harness consists of a grommet body made of rubber or an elastomer, and a resin inner, which is a resin molding, to be assembled to the grommet body. The resin inner is formed by an annular attachment plate to insert and fit a peripheral part into fitting space of the resin inner provided on the grommet body, and a cylinder part protruded from the annular attachment plate. The cylinder part has a plurality of lock pieces arranged in parallel in a circumferential direction by having slits in an axial direction at an interval in a circumferential direction from a projection end, and a lock claw provided on each outside surface of the lock pieces are engaged with the circumference of a through hole of a car body.

Description

  The present invention relates to a grommet for a wire harness, and more specifically, in a grommet for waterproofing, dust-proofing, and sound-insulating, which is externally installed in a through hole of a vehicle body of a wire harness to be routed in a vehicle. In a two-piece grommet in which a grommet body made of a body is combined with an inner made of a resin molded product, it is intended to improve the mounting property to the through hole of the vehicle body and prevent rattling after mounting.

The wire harness routed from the engine room of the automobile through the through hole in the vehicle body panel to the passenger compartment is fitted with a grommet and installed in the through hole to provide waterproof, dustproof, and sound insulation from the engine compartment to the passenger compartment. ing.
As this type of grommets, there are generally used two-piece grommets in which a single-piece grommets made of only an elastic body made of rubber or elastomer and a grommet body made of an elastic body are combined and fixed with a resin inner of a resin molded product. ing.

  The present applicant provides the two-body grommet in JP-A-9-322361. As shown in FIGS. 8A and 8B, the grommet is assembled by fitting the cylindrical portion 110a of the resin inner 110 into the large-diameter cylindrical portion 100a of the grommet body 100. The elastic lock pieces 110b that are folded back from the tip of the cylinder portion are provided at four locations (two locations facing each other in the case of the small grommet) at 90 ° intervals of the cylinder portion 110a of the resin inner 110, and the outer surface of the elastic lock piece 110b Is provided with a lock claw 110c. On the other hand, a seal lip portion 100b is provided on the distal end side of the large-diameter cylindrical portion 100a of the grommet body 100. The cylindrical portion 110 a of the resin inner 110 is passed through the through hole 121 provided in the vehicle body 120, and the lock claw 110 c is locked from one side to the periphery of the through hole 121, and the grommet body 100 is attached to the other end surface of the periphery of the through hole 121. The seal lip portion 100b is pressed.

Japanese Patent Laid-Open No. 9-322361

The two-piece grommet provided with the resin inner is more expensive to manufacture than the one-piece grommet consisting only of the elastic body, but when the resin inner is inserted and locked in the through hole of the vehicle body panel, a locking sound is generated and a feeling of moderation is generated. Will occur. Therefore, there is an advantage that the worker can confirm the end of the locking work.
However, since the resin inner is a resin molded product and has rigidity, and the portion through which the through hole of the vehicle body is inserted is the cylindrical portion 110a, the axial core of the resin inner cylindrical portion 110a and the through hole 121 are concentric. If they do not match, it will be difficult to insert into the through hole 121. In addition, it is necessary to insert the grommet in a right angle direction with respect to the vehicle body panel, and if the grommet insertion posture is inclined, there is a problem that the resin inner cylindrical portion 110a cannot be inserted into the through hole 121.
Further, the lock claw 110c of the resin inner 110 has a shape in which the outer surface of the elastic lock piece 110b that protrudes from the tip of the cylindrical portion 110a is protruded, so that it is elastically locked when inserted into the through hole 121 of the vehicle body panel. The piece 110b and the lock claw 110c bend inward. Due to this bending, an overstroke occurs, and the design is designed to allow for the clearance corresponding to the overstalk, and there is also a problem that rattling increases when the grommet is attached to the vehicle body.

  The present invention intends to solve the above problem, and in a two-piece grommet in which the resin inner is combined with the grommet body, the shaft center of the through hole of the vehicle body and the grommet coincide with each other, and the grommet of the grommet with respect to the through hole. Even if the insertion direction is slanted, the main problem is to enable insertion into a through-hole and allow flexible handling.

In order to solve the above problems, the present invention is a grommet that is externally mounted on a wire harness routed in a vehicle and is attached to a through hole of a vehicle body,
It consists of a grommet body made of rubber or elastomer, and a resin inner of a resin molded product assembled to the grommet body,
The resin inner is composed of an annular mounting plate portion that inserts and locks a peripheral edge into a resin inner locking space provided in the grommet body, and a cylindrical portion that protrudes from the annular mounting plate portion,
The cylindrical portion is composed of a plurality of locking pieces spaced in the circumferential direction from the projecting end and slits in the axial direction and arranged in parallel in the circumferential direction, and lock claws provided on the outer surface of each locking piece penetrate through the vehicle body. A grommet for a wire harness is provided that is configured to be locked to the periphery of a hole.

As described above, conventionally, the resin inner is provided with four lock pieces at two positions or two opposite positions at a 90 degree interval from the tip of the cylinder part. The slit is divided into a plurality of pieces, and a lock claw is provided on each divided piece to make the divided piece a lock piece. In this way, the cylinder portion is composed of a large number of lock pieces to subdivide the lock structure. Thereby, even if it inserts a grommet from the diagonal direction with respect to the through-hole of a vehicle body, since a lock piece bends, a grommet can be inserted in a through-hole.
Further, since the lock claw provided on the outer surface of each lock piece constituting the cylinder portion is locked to the periphery of the through hole of the vehicle body, a locking sound can be generated between the lock claw and the vehicle body at the time of locking. .

The grommet of the present invention is a grommet to be attached to a through hole with a burring of a vehicle body,
The grommet body is provided with a small-diameter cylindrical portion through which the electric wire group of the wire harness is closely inserted, an annular projecting portion projecting from the outer peripheral surface of the small-diameter cylindrical portion, and an axially projecting direction from the tip of the annular projecting portion A large-diameter cylindrical portion, and an annular refractive protruding portion protruding in the inner diameter direction from the tip of the large-diameter cylindrical portion,
The refracting protrusion includes an outer periphery refracting portion protruding in an inner diameter direction from a tip of a large-diameter cylindrical portion, an axial refracting portion refracted in an axial direction from the tip of the outer periphery refracting portion, and the axial refracting portion. An inner peripheral refracting portion projecting in the inner diameter direction from the tip, providing a resin inner locking space between the refracting protrusion and the large-diameter cylindrical portion, and an inner peripheral surface of the axial refracting portion of the refracting protrusion While the seal lip is projected on the
Each lock piece constituting the cylindrical portion of the resin inner has a lock claw protruding from the outer surface at an intermediate position in the axial length direction, and the outer surface on the base side from the lock claw from the periphery of the through hole of the vehicle body It is preferable that a protruding burring contact surface is formed, and an annular space for inserting a burring on the vehicle body side is formed between the burring contact surface of the lock piece and the seal lip of the grommet body.

  With the above configuration, the burring protruding from the through hole of the vehicle body is inserted into an annular space for inserting the burring formed between the lock piece of the resin inner and the seal lip of the grommet body, and the grommet is formed on the outer peripheral surface of the burring. The seal lip of the main body is pressed to press the inner peripheral surface of the burring against the burring contact surface on the base side of the lock piece. In this way, because the resin inner lock piece is in direct contact with the burring, the bent lock piece can be returned quickly, and the overstroke is reduced and the play between the lock piece and the burring occurs. It can be lost.

Therefore, the outer diameter of the cylindrical portion formed of the plurality of lock pieces of the resin inner is set to be the same as the inner diameter of the burring protruding from the periphery of the through hole of the vehicle body.
When the protruding dimension of the seal lip on the grommet main body side is increased, the outer diameter of the cylindrical portion may be slightly smaller than the inner diameter of the burring.

It is preferable that the number of the locking pieces constituting the split inner cylinder portion of the resin inner is in the range of 4-30.
When the through hole of the vehicle body is small, a small grommet is attached. In that case, four lock pieces divided at intervals of 90 degrees may be used. The large grommet is divided into 30 lock pieces. Specifically, when the circumferential length of each lock piece is in the range of 5 mm to 10 mm, each lock piece can be deformed without difficulty.
The gap between adjacent lock pieces is preferably 5 mm to 20 mm.

Protruding the annular protrusion from the middle or one end in the length direction of the small diameter cylindrical portion of the grommet body,
The annular protrusion preferably has a shape in which an inner peripheral side continuous with the small-diameter cylindrical portion is refracted in a mountain shape in the axial direction, and an annular mounting plate portion of resin inner is fitted to the outer peripheral portion.

  Further, the large-diameter cylindrical portion is provided at one end side at the outer peripheral end of the annular protrusion of the grommet body, and the reduced-diameter cylindrical portion is protruded at the other end, and the outer peripheral surface of the small-diameter cylindrical portion is provided at the distal end. It is preferable that an overlapping cylindrical portion is provided so as to be taped and fixed to the small-diameter cylindrical portion so that the reduced-diameter cylindrical portion is a sound-insulating sealed space.

  As described above, in the two-piece grommet in which the resin inner according to the present invention is combined with the grommet body, the cylindrical portion inserted into the through hole of the resin inner having rigidity is composed of a large number of lock pieces arranged in parallel in the circumferential direction. It is easy to bend. Therefore, even when the grommet to be inserted into the through hole of the vehicle body is inclined with respect to the axis of the through hole, the grommet can be inserted, and the grommet can be easily inserted into the through hole. Therefore, when inserting the grommet into the through hole, it is not necessary to pay close attention to the insertion posture of the grommet, and the working efficiency can be improved.

  Further, when a lock claw is projected on the outer surface of the lock piece and the outer surface of the lock piece on the base side from the lock claw is brought into contact with the inner peripheral surface of the burring protruding from the peripheral edge of the through hole, When the lock piece is inserted, the lock piece can be quickly returned from the inwardly bent state, and the overstroke of the lock piece can be eliminated to prevent rattling at the contact surface between the lock piece and the burring.

It is a perspective view of the state where the grommet of the first embodiment was externally mounted on the wire harness and mounted in the through hole of the vehicle body. It is sectional drawing of FIG. It is a principal part expanded sectional view of the said grommet. It is sectional drawing which shows the state which inserts the said grommet in the through-hole of a vehicle body. (A) and (B) are principal part expanded sectional views which show the process of inserting and latching the said grommet to a through-hole. It is sectional drawing of the grommet of 2nd Embodiment. It is principal part sectional drawing of the grommet of 3rd Embodiment. (A) (B) is drawing which shows a prior art example.

Hereinafter, embodiments of a grommet for a wire harness according to the present invention will be described with reference to the drawings.
The grommet of the present invention is a grommet that is externally mounted on a wire harness routed from an engine room of a vehicle to a vehicle compartment and is attached to a through hole formed in a dash panel of a vehicle body.
The grommet is a two-piece grommet including a grommet body made of rubber or elastomer and a resin inner of a resin molded product assembled to the grommet body.

1 to 5 show a grommet according to the first embodiment.
The grommet 1 is a grommet that is attached to a through hole 51 with a burring provided in the dash panel 50, and includes the grommet main body 2 and the resin inner 10.

  The grommet main body 2 includes a small-diameter cylindrical portion 3 through which the wire group of the wire harness W / H is closely inserted and an annular projecting portion 4 protruding from an outer peripheral surface at an intermediate position in the length direction of the small-diameter cylindrical portion 3. A large-diameter cylindrical portion 5 projecting in the axial direction from the distal end of the annular projecting portion 4, an annular refractive projecting portion 6 projecting in the inner diameter direction from the distal end of the large-diameter cylindrical portion 5, and the refractive projecting portion 6. It consists of a projecting seal lip 7.

  The annular projecting portion 4 has its inner peripheral portion 4a refracted in a mountain shape in the axial direction. The refraction protrusion 6 includes an outer periphery refraction part 6a that protrudes in the inner diameter direction from the tip of the large-diameter cylindrical part 5, and an axial refraction part 6b that is bent in the axial direction from the front end of the outer periphery refraction part 6a. And an inner periphery refracting portion 6c projecting in the inner diameter direction from the tip of the axial direction refracting portion 6b. A resin inner locking space 8 is provided between the refracting protrusion 6 and the large-diameter cylindrical part 5, and the seal lip 7 protrudes from the inner peripheral surface of the axially refracting part 6 b of the refracting protrusion 6. .

  The inner resin 10 has an annular mounting plate 11 that is set over the annular projection 4 of the grommet body 2, and a resin inner locking space 8 of the grommet body 2 that protrudes from the outer peripheral edge of the annular mounting plate 11. And a cylindrical portion 12 projecting from one surface of the annular mounting plate portion 11. The central hole 11 h of the annular mounting plate portion 11 is externally fitted to an inner peripheral portion 4 a that protrudes in a mountain shape of the annular protruding portion 4 of the grommet body 2. Further, the cylindrical portion 12 of the resin inner 10 protrudes from the protruding end of the large diameter cylindrical portion 5 of the grommet body 2, and the small diameter cylindrical portion 3 of the grommet main body 2 further protrudes from the tip of the cylindrical portion 12 of the resin inner 10. I am letting.

  The cylindrical portion 12 is composed of a plurality of lock pieces 15 which are spaced in the circumferential direction from the projecting end and have slits 13 in the axial direction and arranged in parallel in the circumferential direction. The slit 13 is inserted up to the connecting portion with the annular projecting portion 4, and the cylindrical portion 12 is a divided cylindrical portion made of the lock piece 15. In addition, although the slit 13 is inserted to a location close to the connection position with the annular projecting portion 4, a cylindrical portion having a short axial direction continuing to the annular projecting portion 4 may be left.

  The number of the plurality of lock pieces 15 divided by the slit 13 is appropriately set according to the size of the grommet, etc., and is preferably in the range of 4-30, and the circumferential dimension of one lock piece 15 is 5 mm. It is preferable to set it as the range of -10 mm. In the grommet 1 of the present embodiment, the number of lock pieces 15 is 24.

The plurality of lock pieces 15 constituting the cylindrical portion 12 are elongated rectangular pieces that protrude in the axial direction from the annular mounting plate portion 11, and lock claws 16 that protrude in a triangular shape on the outer surface of a substantially central portion in the length direction. Is provided. The locking surface 16 a of the lock claw 16 is positioned outward in the axial direction from the protruding position of the seal lip 7 of the grommet body 2.
Further, the base side of the lock piece 15 between the connection points of the lock claw 16 and the annular mounting plate portion 11 is a burring contact surface 17. The burring contact surface 17 is located opposite to the seal lip 7 of the grommet body 2, and a burring for inserting a burring 52 protruding from the peripheral edge of the through hole 51 between the seal lip 7 and the burring contact surface 17 of the lock piece 15. An annular space 18 for insertion is provided. Therefore, the outer diameter of the cylindrical portion 12 composed of a large number of lock pieces 15 is set to be substantially the same as the inner diameter of the burring 52.

  With this shape, when the burring 52 has passed over the lock claw 16, the burring 52 is inserted into the annular space 18 for inserting the burring, and the seal lip 7 contacts the outer peripheral surface in a pressed state, and the inner peripheral surface. In addition, the burring contact surface 17 of the lock piece 15 is in a pressed state, and the locking surface 16 a of the lock claw 16 is locked to the periphery of the through hole 51.

Further, the front end surface of the inner periphery refracting portion 6 c of the grommet body 2 is brought into contact with the burring contact surface 17.
Each lock piece 15 described above can swing inward and outward with a base end 15a connected to the annular mounting plate portion 11 as a fulcrum. In this way, by dividing the cylindrical portion 12 into a large number of lock pieces 15, the lock claw 16 is easily bent inward when the lock claw 16 comes into contact with the burring 52. It is easy to return to the original.

  Next, the grommet 1 is attached to the wire harness W / H, the wire harness W / H is routed to the automobile and passed through the through hole 51 with the burring 52 of the dash panel 50, and the grommet 1 is inserted into the through hole 51. The work of mounting will be described.

  First, the grommet 1 is completed by assembling the resin inner 10 to the grommet body 2. That is, the cylindrical portion 12 of the resin inner 10 is set so as to be fitted into the inner peripheral refracting portion 6c of the refractive protruding portion 6 of the grommet body 2, and the annular mounting plate portion 11 is overlapped with the annular protruding portion 4 of the grommet main body 2. The locking portion 11 a is fitted into the resin inner locking space 8 of the grommet body 2.

  The wire harness W / H is penetrated while the small diameter cylindrical portion 3 of the grommet 1 assembled as described above is expanded with an expansion jig (not shown). After the penetration, the adhesive tape T is wound around both ends of the small diameter cylindrical portion 3 in the length direction and the wire harness W / H, and the grommet 1 is fixed to the wire harness W / H.

  The wire harness W / H to which the grommet 1 is attached as described above is routed in the automobile. As shown in FIG. 4, a burring 52 projects toward the engine room (X) from the periphery of a through hole 51 formed in the dash panel 50. The wire harness W / H is inserted through the through hole 51 from the engine room (X) side toward the vehicle compartment (Y).

  When the grommet 1 reaches the protruding end of the burring 52 protruding from the through hole 51, the annular burring 52 comes into contact with the outer peripheral surface of a large number of lock pieces 15 arranged in parallel in the annular shape, as shown in FIG. The protruding position of the nail 16 is reached. In order for the burring 52 to get over the lock claw 16, each lock piece 15 is bent inward from the base end 15a. Thereby, the burring 52 gets over the lock claw 16 and is inserted into the burring insertion annular space 18 sandwiched between the burring contact surface 17 on the base side of the lock piece 15 and the seal lip 7 of the grommet body 2.

The outer peripheral surface of the burring 52 inserted into the annular space 18 is in contact with the seal lip 7 on the grommet body 2 side, and the inner peripheral surface of the burring 52 is in contact with the burring contact surface 17 of the lock piece 15 of the resin inner 10. The inner and outer peripheral surfaces are sealed. The lock piece 15 of the resin inner 10 is bent inward when the lock claw 16 is pushed by the burring 52, but when the lock claw 16 is detached from the burring 52, as shown in FIG. Swing outward to return to the original state. Thus, it is not necessary to allow for the overstroke by the lock piece 15 returning to the original shape at an early stage, and the burring contact surface 17 of the lock piece 15 can be brought into contact with the burring 52 without backlash.
In addition, the lock claw 16 of the resin inner 10 is engaged with the peripheral edge of the through hole 51 corresponding to the base of the burring 52 to prevent the grommet 1 from coming off the through hole 52.

  In the grommet 1 having the above-described configuration, the cylinder portion on which the lock claw 16 is provided is divided into a large number of lock pieces 15 so that each lock piece 15 is easily bent. Therefore, even if the insertion direction of the grommet 1 is shifted from the axial direction of the through hole 51 and is obliquely inserted, the divided lock pieces 15 are bent, and the grommet 1 can be inserted and can be flexibly handled.

FIG. 6 shows a grommet according to the second embodiment.
The grommet 1 has the large-diameter cylindrical portion 5 protruding from one surface of the outer peripheral end of the annular protrusion 4 of the grommet body 2, and the reduced-diameter cylindrical portion 30 protruding from the other surface, and a small-diameter cylindrical portion at the tip thereof. A cylindrical portion 31 is provided so as to overlap the outer peripheral surface 3. A pressure-sensitive adhesive tape T is wound around and fixed to the cylindrical portion 31 and the small-diameter cylindrical portion 3 to provide a sound insulation sealed space 33.
Since other configurations and operational effects are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the first and second embodiments, a resin inner mounting portion is provided in the middle of the length direction of the small diameter cylindrical portion of the grommet body, and the resin inner is assembled, but the resin is attached to one end of the small diameter cylindrical portion in the length direction. An inner attachment portion may be provided, and the resin inner may be attached to the tip of the small diameter cylindrical portion of the grommet body.

FIG. 7 shows a grommet 40 of the third embodiment.
The grommet 40 is provided with the annular protruding portion 4, the large diameter cylindrical portion 5, the refractive protruding portion 6 and the seal lip 7 at the tip of the small diameter cylindrical portion 3 of the grommet body 2. The seal lip 7 protrudes from the outer surface of the outer periphery refracting portion 6 a of the refracting protrusion 6.
The resin inner 10 is set at the tip of the grommet body 2. The resin inner 10 divides the cylindrical portion 12 into a number of lock pieces 15 as in the first embodiment. Each lock piece 15 is provided with a lock claw 47 that is folded outward from the tip, which is different from the first embodiment.
Other configurations are the same as those of the first embodiment, and the same reference numerals are given and the description thereof is omitted.
The grommet 40 is inserted into the through hole 55 without burring, the lock claw 47 is engaged with the periphery of the through hole 55, and the seal lip 7 is pressed against the periphery surrounding the through hole 55.

DESCRIPTION OF SYMBOLS 1 Grommet 2 Grommet main body 3 Small-diameter cylinder part 4 Annular protrusion part 5 Large-diameter cylinder part 6 Refraction protrusion part 7 Seal lip 8 Resin inner locking space 10 Resin inner 11 Annular support plate part 12 Tube part 13 Slit 15 Lock piece 16 Lock claw 18 Annular space for inserting burring 50 Dash panel 51 Through hole 52 Burring W / H wire harness

Claims (5)

A grommet that is externally mounted on a wire harness that is routed in a vehicle, and is attached to a through hole of a vehicle body,
It consists of a grommet body made of rubber or elastomer, and a resin inner of a resin molded product assembled to the grommet body,
The resin inner is composed of an annular mounting plate portion that inserts and locks a peripheral edge into a resin inner locking space provided in the grommet body, and a cylindrical portion that protrudes from the annular mounting plate portion,
The cylindrical portion is composed of a plurality of locking pieces spaced in the circumferential direction from the projecting end and slits in the axial direction and arranged in parallel in the circumferential direction, and lock claws provided on the outer surface of each locking piece penetrate through the vehicle body. A grommet for a wire harness, wherein the grommet is configured to be engaged with a peripheral edge of a hole. The grommet body is provided with a small-diameter cylindrical portion through which the electric wire group of the wire harness is closely inserted, an annular projecting portion projecting from the outer peripheral surface of the small-diameter cylindrical portion, and an axially projecting direction from the tip of the annular projecting portion A large-diameter cylindrical portion, and an annular refractive protruding portion protruding in the inner diameter direction from the tip of the large-diameter cylindrical portion,
The refracting protrusion includes an outer periphery refracting portion protruding in an inner diameter direction from a tip of a large-diameter cylindrical portion, an axial refracting portion refracted in an axial direction from the tip of the outer periphery refracting portion, and the axial refracting portion. An inner peripheral refracting portion projecting in the inner diameter direction from the tip, providing a resin inner locking space between the refracting protrusion and the large-diameter cylindrical portion, and an inner peripheral surface of the axial refracting portion of the refracting protrusion While the seal lip is projected on the
Each lock piece constituting the cylindrical portion of the resin inner has a lock claw protruding from the outer surface at an intermediate position in the axial length direction, and the outer surface on the base side from the lock claw from the periphery of the through hole of the vehicle body The wire according to claim 1, wherein the wire has a shape as a protruding burring contact surface, and an annular space for inserting a burring on the vehicle body side is formed between the burring contact surface of the lock piece and the seal lip of the grommet body. Grommet for harness.   3. The wire harness according to claim 1, wherein the number of lock pieces constituting the cylindrical portion of the resin inner is in a range of 4 to 30, and a circumferential length of each lock piece is in a range of 5 mm to 10 mm. Grommet.   The annular projecting portion protrudes from the middle or one end of the small diameter cylindrical portion of the grommet body, and the annular projecting portion refracts the inner peripheral side continuous with the small diameter cylindrical portion in a mountain shape in the axial direction. The grommet for a wire harness according to any one of claims 1 to 3, wherein the annular mounting plate portion of the resin inner is fitted into the portion.   The large-diameter cylindrical portion is provided on one surface side of the outer peripheral end of the annular protrusion of the grommet body, the reduced-diameter cylindrical portion is protruded on the other surface side, and the cylindrical portion that overlaps the outer peripheral surface of the small-diameter cylindrical portion is provided at the distal end. The grommet for a wire harness according to any one of claims 1 to 4, wherein the grommet is provided so as to project and is tightly wound with the small-diameter cylindrical portion to form a sound insulation sealed space.

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