JP4062218B2 - Grommet - Google Patents

Description

  The present invention relates to a grommet fitted on a wire harness, and more specifically, a seal lip is securely brought into close contact with a peripheral edge of a through hole of a vehicle body panel.

  Conventionally, as shown in FIGS. 7 (A) and 7 (B), a wire harness to be routed in an automobile is routed through a through hole of a vehicle body panel from the outside of an engine room or the like to the indoor side. Or the grommet 1 which consists of elastic bodies, such as an elastomer, is externally fitted by the wire harness W / H. The outer peripheral surface of the large-diameter cylindrical portion 1a of the grommet 1 is provided with a vehicle body locking groove 1b for locking the vehicle body. Of the side walls of the vehicle body locking groove 1b, one side wall is shown in FIG. As shown, a seal lip 1c is formed and brought into close contact with the vehicle body panel P to provide waterproof and soundproofing functions.

Generally, when wiring the wire harness W / H to the automobile, the wire harness W / H is passed from the indoor side (X) to the outdoor side (Y), and the grommet 1 is connected from the outdoor side (Y) to the wire harness W / H. The tightly attached cylinder portion 1d is pulled to bring the vehicle body locking groove 1b into close contact with the peripheral edge of the through hole 2, and the seal lip 1c is brought into close contact with the outdoor side surface P-1 of the vehicle body panel P for waterproofing.
As shown in FIG. 7C, the seal lip 1c to be brought into close contact with the vehicle body panel P normally has its tip inner surface elastically attached to the surface of the vehicle body panel P over the entire periphery. As shown in D), some of them may be caught inward or rolled up. In such a state, a gap may be formed between the seal lip 1c and the vehicle body panel P, and sufficient waterproof and soundproof functions may not be exhibited. Furthermore, when the grommet 1 has an oval shape, such a problem of poor adhesion of the seal lip 1c tends to be more likely to occur due to a delay in the return of the shape of the seal lip 1c at the end on the long diameter side. is there.

  Therefore, in order to solve the above problem, as shown in FIG. 8 (A), a grommet 1 ′ is known in which a protrusion 3 for correcting a seal lip hook is provided on the outer surface of the large-diameter cylindrical portion 1a ′ ( Patent Document 1). In this grommet 1 ′, after the grommet 1 ′ is installed in the through hole 2, as shown in FIG. 8 (B), the protrusion 3 is pulled to temporarily separate the seal lip 1 c ′ from the vehicle body panel P, thereby In a state where the contact surface of the lip 1c ′ with respect to the vehicle body panel P is restored to a flat surface, as shown in FIG. 8C, the protrusion 3 is stopped from pulling and returned to the vehicle body panel P side. As a result, the seal lip 1c ′ is in a normal state where the entire contact surface is in surface contact with the vehicle body panel P, and the waterproof performance of the seal lip 1c ′ can be ensured.

However, since the grommet 1 ′ provided with the protrusion 3 as described above requires an operation of further pulling the protrusion 3 after the grommet 1 ′ is mounted on the vehicle body panel P, the grommet 1 ′ on the vehicle body panel P is required. There is a problem that the mounting process becomes complicated and time-consuming.
JP 2001-99359 A

  The present invention has been made in view of the above-described problems, and an object of the present invention is to ensure that the seal lip can be securely adhered to the vehicle body panel by a normal mounting process of the grommet to the vehicle body panel.

In order to solve the above problems, the present invention is a grommet made of an elastic body that is attached to an automotive wire harness and inserted and locked into a through hole of a vehicle body panel,
Connected to the axial front end of a large-diameter cylindrical part with a body-engagement groove recessed in the outer peripheral surface through a radially projecting annular part on the rear end side of the cylindrical part through which the wire harness is brought into close contact. ,And,
At least three tension pieces extending from the outer periphery of the front side wall provided with the seal lip of the vehicle body locking groove to the front end of the cylindrical portion are provided at intervals in the circumferential direction. Attached to the wire harness together with the front end side of the tape by tape winding,
The seal lip is pulled by the tension piece and pulled away from the vehicle body panel in a state where the tube portion is pulled into the through hole of the vehicle body panel from the front end side and the front side wall of the vehicle body locking groove is passed through the through hole. A grommet is provided in which the seal lip is brought into close contact with the vehicle body panel when the annular portion is restored to its original shape when the pull-in is released.

  According to the above configuration, when the grommet is attached to the through hole of the vehicle body panel, at least three tensile members that are taped and fixed to the cylinder portion together with the wire harness as the wire harness is pulled from the cylinder portion side. The seal lip is lifted away from the vehicle body panel through the piece. As a result, the seal lip is brought into a normal original state without entanglement due to its elastic restoring force, and when the pulling of the wire harness is subsequently released, the seal lip is engulfed all around the vehicle body panel by the elastic return force of the grommet. In addition, it can be adhered in a normal state without twisting. These operations can be performed in conjunction with a normal wire harness pull-in operation when the grommet is attached to the vehicle body panel.

The large-diameter cylindrical portion may have an elliptical cross section, and the four tension pieces may protrude from the centers of the long diameter side and the short diameter side.
When the large-diameter cylindrical part has an elliptical cross section, the end part on the long-diameter side is in a state where it is difficult for the shape to return when passing through the through-hole. The seal lip of the entire circumference can be once separated from the vehicle body panel via the. Thereby, even if the large-diameter cylindrical portion has an elliptical cross section, the seal lip can be securely adhered to the vehicle body panel.

  Further, the rear end portion of the cylindrical portion is disposed in a state of being retracted to the large diameter cylindrical portion side, and the annular portion connecting the large diameter cylindrical portion and the cylindrical portion has a cross section of the wall portion extending from the large diameter cylindrical portion to the cylindrical portion. It is set as the inclination wall which inclines in the opposite side to the protrusion direction of a cylinder part. Accordingly, when the tubular portion is pulled together with the wire harness in the protruding direction, the annular portion is reversed to the tubular portion side so that the tubular portion can easily extend from the large-diameter tubular portion. For this reason, the separation operation of the seal lip from the vehicle body panel by the tension piece fixed to the cylinder portion can be performed more effectively.

  As is clear from the above description, according to the present invention, the seal lip is once separated from the vehicle body panel via the tension piece as the wire harness is pulled in when the grommet is attached to the vehicle body panel. The seal lip can be returned to the normal original state, and then brought into close contact with the vehicle body panel over the entire circumference. Therefore, the waterproof and soundproof functions by the grommet can be surely exhibited. Moreover, since these operations can be performed in conjunction with the pull-in operation of the wire harness when the grommet is attached, the workability is not complicated and can be performed well.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show a grommet 10 according to a first embodiment. The grommet 10 is integrally formed of an elastic body such as rubber or elastomer, and a cylindrical portion 11 through which a wire harness W / H is brought into close contact, and this A thin annular portion 12 projecting radially from the rear end side of the cylindrical portion 11 and a thick large diameter cylindrical portion 13 connected to the tip of the annular portion 12 are provided.

  A body locking groove 14 that engages with the through hole Pa of the vehicle body panel P is annularly formed on the outer peripheral surface of the large-diameter cylindrical portion 13, and the inner periphery of the front side wall 14 a on the annular portion 12 side is sealed lip 15. The rear side wall 14b has a diameter larger than that of the front side wall 14a, and serves as a base portion that comes into close contact with the edge of the through hole Pa from the side opposite to the seal lip 15. The annular portion 12 is connected to the front end in the axial direction of the large-diameter cylindrical portion 13, and the cross section of the wall portion extending from the large-diameter cylindrical portion 13 to the rear end portion of the annular portion 12 is inclined opposite to the protruding direction of the annular portion 12. As the inclined wall 12a, the rear end portion of the annular portion 12 is arranged in the retracted state toward the large-diameter cylindrical portion 13 side. By arranging in this way, the annular portion 12 is easily extended in the protruding direction with respect to the large-diameter cylindrical portion 13.

  On the outer periphery of the front side wall 14 a provided with the seal lip 15 in the vehicle body locking groove 14 of the large diameter cylindrical portion 13, four strips extending to the front end of the cylindrical portion 11 in the axial direction parallel to the cylindrical portion 11. Are provided at equal intervals in the circumferential direction. By pulling the tension piece 16 toward the cylindrical portion 11, the front side wall 14a on which the seal lip 15 is formed can be lifted.

  As shown in FIG. 2 (A), the grommet 10 is passed through a wire harness W / H in which a group of electric wires are converged, and a tape T is wound around the outer periphery of the wire harness W / H together with the front end side of the cylindrical portion 11. 10 is fixed to the wire harness W / H.

Next, a process of mounting the grommet 10 having the above configuration in the through hole Pa of the vehicle body panel P will be described.
As shown in FIG. 2A, the wire harness W / H to which the grommet 10 is attached is passed through the through hole Pa from the cylindrical portion 11 side toward the outdoor side (Y) from the indoor side (X). Next, as shown in FIG. 2 (B), by pulling the wire harness W / H together with the grommet 10 from the cylindrical portion 11 side, the front side wall 14a of the large diameter cylindrical portion 13 is bent in the reduced diameter direction while passing through the through hole Pa. , The vehicle body locking groove 14 is engaged with the inner periphery of the through hole Pa, and the rear side wall 14b is in contact with the rear surface of the vehicle body panel P. Further, when the tubular portion 11 is further pulled together with the wire harness W / H, the annular portion 12 is inverted and protrudes toward the tubular portion 11 side, so that the tubular portion 11 is engaged and fixed in the through hole Pa. The state extends from the portion 13. Along with this, the tension piece 16 having one end fixed to the cylinder portion 11 is also pulled forward, so that the front side wall 14a having the seal lip 15 formed on the inner surface is also pulled via the tension piece 16 and the entire seal lip 15 is pulled. The circumference is separated from the vehicle body panel P. Thereby, when passing through the through hole Pa, the seal lip 15 wound inward or caught is restored to the normal original shape over the entire circumference.

  Next, when the pulling operation of the wire harness W / H with respect to the grommet 10 is released, the cylindrical portion 11, the annular portion 12 and the front side wall 14a are elastically restored to the state shown in FIG. The panel P is in close contact with the entire surface without any gaps. Thereby, the waterproofing and soundproofing function through the through-hole Pa which are the basic functions of the grommet 10 can be exhibited reliably.

  4 and 5 show a second embodiment of the grommet 20, in which the grommet 10 of the first embodiment is inserted from the indoor side (X) toward the outdoor side (Y) and engaged with the vehicle body panel P. On the other hand, the second embodiment shows a type that is mounted from the outdoor side (Y) toward the indoor side (X). For this reason, the rear side wall 24b of the vehicle body locking groove 24 in the large-diameter cylindrical portion 23 is set to have a smaller diameter than the front side wall 24a, and the inclined guide surface for guiding the insertion into the through hole Pa at the end surface portion of the rear side wall 24b. 24c is formed. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.

  Next, a process of mounting the grommet 20 having the above configuration in the through hole Pa of the vehicle body panel P will be described. As shown in FIGS. 4A and 4B, the wire harness W / H to which the grommet 20 is attached is inserted from the large-diameter cylindrical portion 23 side toward the indoor side (X) from the outdoor side (Y). Then, the rear side wall 24b of the large-diameter cylindrical portion 23 passes through the through hole Pa and the vehicle body locking groove 14 engages with the inner periphery of the through hole Pa by the guide of the inclined guide surface 24c. Next, as shown in FIG. 5A, when the wire harness W / H is pulled together with the tube portion 11 from the outdoor side (Y), the seal lip 15 that is in contact with the vehicle body panel P is pulled through the tension piece 16. As a result, the vehicle body panel P is once separated from the vehicle body panel P over the entire circumference, and the seal lip 15 is brought into a normal state with no stagnation or entanglement. Next, when the pulling operation of the wire harness W / H is released, the cylindrical portion 11, the annular portion 12 and the seal lip 15 are elastically restored, so that the seal lip 15 is disposed on the vehicle body panel P over the entire circumference as shown in FIG. It is in a state of evenly adhering to each other, and the waterproof and soundproofing functions are reliably exhibited. Thus, also in 2nd Embodiment, the seal lip 15 is once separated from the vehicle body panel P by the effect | action of the tension | pulling piece 16 interlock | cooperated with pulling operation of the wire harness W / H, and the seal lip 15 is attached to the vehicle body panel P. It is possible to return to a fully intimate shape.

FIG. 6 shows a third embodiment of the grommet 30, corresponding to the case where the through-hole Pa of the vehicle body panel P is a long hole, the large-diameter cylindrical portion 33 has an elliptical cross section, and each of the long-diameter side 30 a and the short side thereof. Four tension pieces 36 are projected from the center of the diameter side 30b. Since other shapes are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.
The ellipse-shaped grommet 30 is particularly easy to be deformed due to its large bending dimension when the long diameter side 30a passes through the through-hole Pa, and it may be difficult to return to the normal shape. In the present embodiment, in particular, the shape of the normal shape is obtained by pulling the seal lip 15 via the tension piece 36 in conjunction with the pull of the wire harness W / H by projecting the tension piece 36 also on the long diameter side 30a. Can be reliably restored.

  In each of the above embodiments, an example is shown in which four tension pieces are provided at equal intervals. However, at least three tension pieces may be provided, and the intervals between the tension pieces are precisely equal. It may not be, and it may be made to concentrate on the part which is easy to change according to the shape of a grommet.

1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a perspective view of a grommet, and FIG. (A) is sectional drawing which shows the process of mounting | wearing a vehicle body panel with a grommet (B). It is sectional drawing of the state which attached the grommet to the vehicle body panel. A 2nd embodiment is shown and (A) and (B) are sectional views showing a process of attaching a grommet to a body panel. (A) (B) is sectional drawing which shows the process of mounting | wearing a vehicle body panel with a grommet same as the above. It is a perspective view which shows the grommet of 3rd Embodiment. (A)-(D) are schematic which shows a prior art example. (A)-(C) are figures which show a prior art example.

Explanation of symbols

10, 20, 30 Grommet 30a Long diameter side 30b Short diameter side 11 Tube portion 12 Annular portion 13, 23, 33 Large diameter tube portion 14 Car body locking groove 14a, 24a Front side wall 15 Seal lip 16, 36 Tensile piece W / H wire Harness P Body panel Pa Through hole T Tape

Claims (2)

A grommet made of an elastic body that is attached to a wire harness for an automobile and inserted and locked into a through hole of a vehicle body panel,
Connected to the axial front end of a large-diameter cylindrical part with a body-engagement groove recessed in the outer peripheral surface through a radially projecting annular part on the rear end side of the cylindrical part through which the wire harness is brought into close contact. ,And,
At least three tension pieces extending from the outer periphery of the front side wall provided with the seal lip of the vehicle body locking groove to the front end of the cylindrical portion are provided at intervals in the circumferential direction. Attached to the wire harness together with the front end side of the tape by tape winding,
The seal lip is pulled by the tension piece and pulled away from the vehicle body panel in a state where the tube portion is pulled into the through hole of the vehicle body panel from the front end side and the front side wall of the vehicle body locking groove is passed through the through hole. A grommet configured such that when the pull-in is released, the annular portion returns to its original shape so that the seal lip is in close contact with the vehicle body panel.   2. The grommet according to claim 1, wherein the large-diameter cylindrical portion has an elliptical cross section, and the four tension pieces protrude from the centers of the long diameter side and the short diameter side.

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