JP5200427B2 - Grommet - Google Patents

Description

  The present invention relates to a grommet, and more specifically, when a grommet to be attached to a wire harness routed in an automobile is inserted through a through hole of a vehicle body panel, the grommet's through posture is corrected and the annular grommet provided in the grommet is provided. The entire periphery of the vehicle body locking recess can be accurately locked to the periphery of the through hole.

  The wire harness routed from the engine room of the automobile to the passenger compartment side is routed through a through-hole drilled in the dash panel (or cowl panel) that separates the engine room from the passenger compartment. In order to prevent water from entering the passenger compartment from the hole and intrusion of dust, a grommet integrally molded with rubber or elastomer is externally mounted on the wire harness, and the vehicle body locking recess provided in the grommet is locked to the periphery of the through hole. Yes.

As this type of grommet, there is a so-called one-motion grommet in which a vehicle body locking recess provided on the outer periphery of the grommet is locked to the periphery of the through hole by simply pushing the grommet into the through hole of the vehicle body panel from one direction. Many are provided in the 32855 publication.
As shown in FIG. 7, the one-motion grommet includes a small-diameter cylindrical portion 2 and a large-diameter cylindrical portion 3 that is continuous with the small-diameter cylindrical portion 2. The vehicle body locking recess 4 is provided, and the both side walls sandwiching the groove 4a of the vehicle body locking recess 4 are a vertical wall 4b on the large diameter tip side and an inclined wall 4c on the opposite small diameter side. The grommet 1 is passed through the wire harness W / H from the small-diameter cylindrical portion 2 to the hollow portion of the enlarged-diameter cylindrical portion 3, and is fixed by a tape T on the distal end side of the small-diameter cylindrical portion 2.

  As shown in FIG. 7, the grommet 1 is inserted into the through hole H of the vehicle body panel P from the engine room side (X), and then the vehicle compartment is mounted on the through hole of the vehicle body panel. The small-diameter cylindrical portion 2 is pulled from the side (Y) to deform the inclined wall 4c so as to be crushed inward, pass through the through hole H, and the inclined wall 4c and the vertical wall 4b that return after passing through the both sides of the vehicle body panel P. The vehicle body locking recess 4 of the grommet 1 is attached to the through hole H of the vehicle body panel P.

JP 2003-32855 A

When the grommet 1 is inserted into the through hole H and pulled in the step of attaching the grommet to the through hole, the center line of the through hole H and the central axis of the grommet 1 are aligned to form a straight direction S0. The entire circumference of one annular body locking recess 4 can be accurately locked to the entire periphery of the through hole H.
However, at the time of attaching the grommet 1 to the through hole H, the small-diameter cylindrical portion 1a is inclined from the engine room side (X) in the oblique directions S1, S2 with respect to the center line S0 of the through hole H as shown in FIG. Or when pulling from the passenger compartment (Y), it may be pulled in the diagonal directions S3 and S4. In particular, the engine harness (also referred to as the front harness) routed from the engine room side (X) to the passenger compartment side (Y) has a large amount of electric wire and is heavy, so the grommet 1 attached to the wire harness also requires strength. Therefore, the operation of pulling the vehicle body locking recess 4 of the grommet 1 to the periphery of the through hole H by pulling from the indoor side requires a large tensile force, and therefore often deviates from a straight direction.
When the grommet 1 is inserted in an oblique direction or pulled in an oblique direction, the vehicle body locking recess 4 is locked to the periphery of the through hole H in one piece, and as shown in FIG. The vehicle body locking recess 4 is not locked to the entire periphery of the vehicle, and a portion that is not partially locked occurs. In this state, the waterproof and dustproof performance is deteriorated, and the vehicle is vibrated and the grommet 1 may be detached from the through hole H.
The above-described problem is not limited to the engine harness, and is a problem that occurs at a place where the grommet is inserted through the through hole of the vehicle body panel.

  The present invention has been made in view of the above problems. The grommet is inserted and retracted through the through hole of the vehicle body panel so that the center of the grommet is aligned with the through hole. It is an object to be able to reliably lock the entire circumference of the hole.

In order to solve the above-mentioned problems, the present invention is made of rubber or elastomer that is locked to a through-hole of a vehicle body panel in a state of being sheathed on an automobile wire harness, and has a small-diameter cylindrical portion and a thin-walled portion that continues to the small-diameter cylindrical portion. An enlarged cylindrical portion, a tip thick portion projecting in the direction perpendicular to the axis continuous with the large-diameter tip of the enlarged diameter cylindrical portion, and an annular outer surface between the thick tip portion and the enlarged cylindrical portion A grommet that includes a vehicle body locking recess provided on the small diameter cylindrical portion and is inserted into the through-hole from the small diameter cylindrical portion side to lock the vehicle body locking recess to the vehicle body panel,
With an interval in the circumferential direction on the outer peripheral surface of the expanded diameter cylindrical portion,
A plurality of protruding step portions extending in the axial direction from the small diameter cylindrical portion to the vehicle body engaging recess portion are provided, and a virtual outer diameter D1 connecting the outer surfaces of the protruding step portions is smaller than the inner diameter d of the through hole of the vehicle body panel. A grommet is provided in which ribs for confirming the center position are provided concentrically on the outer surface of each protruding step.

As described above, if the rib for center position confirmation is provided concentrically with the central axis of the grommet at a position close to the small-diameter cylindrical part side, it is inserted into the through hole of the vehicle body panel from the small-diameter cylindrical part side. In doing so, it is possible to determine at a glance whether or not the grommet is inserted straight with the through hole and the shaft center aligned with each other from the positional relationship with the center confirmation rib at the periphery of the through hole. That is, if the dimensions between the ribs for center confirmation and the peripheral edge of the through hole are substantially the same, it is inserted straight. If the dimensions between the ribs and the through hole are greatly different, the grommet is inserted diagonally. Will be. Therefore, the operator can correct the insertion posture so that the dimensions of the ribs and the through holes are substantially the same.
In addition, the center confirmation rib is provided on the small-diameter cylindrical portion side from the position where the protruding step portion of the grommet contacts the peripheral edge of the through hole, so that the operator can notice the oblique insertion and correct the insertion posture. Is before the protruding stepped portion of the grommet abuts on the periphery of the through hole, so that the insertion posture can be corrected smoothly, the grommet is not damaged, and the operator is not burdened.

Further, the grommet of the present invention is spaced in the circumferential direction on the outer peripheral surface of the expanded diameter cylindrical portion,
A plurality of protruding step portions extending in the axial direction from the small-diameter cylindrical portion to the vehicle body locking recess are provided, and the outer surface of the protruding step portion is brought into contact with the inner peripheral surface of the through hole of the vehicle body panel, thereby reducing the contact area. Therefore, the insertion force for attaching the grommet to the through hole can be reduced.

The rib for checking the center position is provided on the entire circumferential length of the outer surface of the protruding stepped portion, and the height thereof is such that the virtual outer diameter D1 connecting the tips of the ribs of each protruding stepped portion is larger than the inner diameter d of the through hole. It is set to be smaller.
When the virtual outer diameter D1 connecting the tips of the center position confirmation ribs is larger than the inner diameter d of the through hole, when the grommet is inserted straight into the through hole, the center confirmation rib is positioned at the periphery of the through hole. The insertion force increases at this point in contact. Also, when recognizing that it is inserted in an oblique posture and correcting the insertion posture, it is necessary to do so while bringing the grommet into contact with the peripheral edge of the through hole, so there is a possibility that the outer surface of the grommet may be damaged, and This places a burden on the worker. Therefore, the height of the rib for confirming the center position is set so that the virtual outer diameter D1 connecting the tips of the ribs of each protrusion step portion is smaller than the inner diameter d of the through hole.
Further, the insertion posture can be confirmed more easily by providing the rib over the entire circumferential length of the outer surface of the protrusion step.

More specifically, the vehicle body locking recess of the grommet includes a first wall that is high on the thick-walled end side and a second wall that is low on the enlarged-diameter cylindrical portion with the groove bottom interposed therebetween, and the second wall is bent inward. It is shaped to pass through the through hole, and
There are six or more protruding stepped portions provided on the outer peripheral surface of the diameter-enlarging cylindrical portion, projecting from the continuous end with the small-diameter cylindrical portion, and extending to the projecting end of the second wall of the vehicle body locking recess. The circumferential width of the stepped portion extends in the axial direction as the same,
Projecting amount of the projecting step portion, when inserting the central axis line S1 of the grommet in the orientation coincides with the center SO of the through hole of the body panel to said through hole, the contact point between the inner surface of the through hole the portion up to a position gradually thinned small diameter cylinder portion side end as the maximum protruding amount, the second wall to the tip protrusion amount of the said vehicle body latch recess is bent at the contact point and a fixed, reaches the second wall It is preferable to provide a circumferential groove near the tip.

  As described above, when the shape of the protrusion step portion is set as described above on the outer peripheral surface of the enlarged diameter cylindrical portion, the grommet is inserted into the through hole of the vehicle body panel, and all the ribs for checking the center position are all through holes. Since the outer surface of the protrusion step portion contacts the inner peripheral surface of the through-hole after passing through, it is necessary to bend and push the second wall inward from this contact point. By inserting and strengthening, it is possible to efficiently insert the through hole of the grommet. Moreover, by providing a groove in the circumferential direction in the vicinity of the second wall side of the protrusion step portion, the second wall can be easily deformed to the groove side of the vehicle body locking recess, and the protrusion of the protrusion step portion Since the amount is reduced, the insertion force can be reduced.

Further, the number of the protruding stepped portions provided with the chevron ribs is six or more, preferably eight, and the same width in the circumferential direction is extended in the axial direction, so that the protruding stepped portion on the small diameter cylindrical portion side is provided. The adjacent ridge step portions are adjacent to each other and radially extend toward the tip end side of the second wall, and between the adjacent ridge step portions, a triangular shape composed of the outer peripheral surface of the enlarged diameter cylindrical portion. It becomes the structure where a hollow part arises.
As described above, when the protruding step portions are densely arranged on the small diameter side, the center position confirmation ribs provided on the small diameter cylindrical portion side are close to each other, and the difference in dimensions between the ribs and the through holes is facilitated. Also, it is advantageous in correcting the direction at the time of oblique insertion. Moreover, when inserting straightly, even if it arrange | positions a protrusion step part closely, since it does not contact the internal peripheral surface of a through-hole, it will not become an increase in insertion force.
Further, since the area of the thin hollow portion increases toward the vehicle body engagement concave portion side, it becomes easy to bend in the diameter reducing direction, and the insertion force can be reduced.

  According to the present invention, when inserting into the through hole of the vehicle body panel from the small-diameter cylindrical portion side of the grommet, the size between the ribs for checking the center position and the peripheral edge of the through hole is observed while being inserted. It is possible to determine at a glance whether is a straight insertion posture but an oblique insertion posture. Therefore, the operator can insert the grommet while correcting the straight insertion posture. Therefore, the entire circumference of the vehicle body locking recess of the grommet can be accurately locked to the entire periphery of the through hole of the vehicle body panel.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 6.
The grommet 10 of this embodiment is attached in advance to the grommet 10 that is externally mounted on the wire harness W / H that penetrates the through hole H of the dash panel P from the engine room side (X), similarly to FIG.

  The grommet 10 is integrally formed of rubber, and the enlarged diameter cylindrical portion 13 is made to be continuous with the small diameter cylindrical portion 11 that is the insertion side front portion. The diameter-expanding cylindrical portion 13 is conically expanded from the continuous end of the small-diameter cylindrical portion 11, and a distal end thick portion 12 that protrudes in a direction orthogonal to the axial direction of the grommet is connected to the larger-diameter distal end side. . A vehicle body locking recess 14 is formed in an annular shape on the outer peripheral surface between the distal end thick portion 12 and the enlarged diameter cylindrical portion 13.

Both side walls of the vehicle body locking recess 14 are composed of a first wall 14a on the distal end thick portion 12 side and a second wall 14c on the enlarged diameter cylindrical portion 13 side facing each other across the groove 14b. The wall 14a has a high protruding amount from the bottom surface of the groove 14b, the second wall 14c is low, and the height is changed. A lip 14e for pressure contact is provided on the bottom surface of the groove 14b.
Along the outer peripheral surface of the enlarged-diameter cylindrical portion 13, an axial interval extends from the small-diameter side continuous with the small-diameter cylindrical portion 11 to the tip of the second wall 14 c of the vehicle body locking recess 14. A plurality of protruding step portions 20 are provided. The ridge step portion 20 protrudes from the outer peripheral surface of the diameter-expanded cylindrical portion 13 in a step-like manner and is formed into a rib shape.
In the present embodiment, eight ridge step portions 20 are provided, each ridge step portion 20 has the same shape, the circumferential width W is the same, and the second end of the vehicle body locking recess 14 from the small-diameter cylindrical portion side end P1. It extends in the axial direction to the tip point P2 of the wall 14c.

For confirming the center position on the outer surface of each ridge step portion 20 on the small diameter cylindrical portion 11 side where the virtual outer diameter D1 connecting the outer surface 20a of the ridge step portion 20 is smaller than the inner diameter d of the through hole H of the vehicle body panel P. The ribs 21 are concentrically provided over the entire length in the circumferential direction.
The height of the rib 21 for checking the center position is set so that the virtual outer diameter D1 connecting the tips of the ribs 21 of each protruding step 20 is smaller than the inner diameter d of the through hole.

As shown in FIG. 3, the protruding amount G of the protrusion step portion 20 protruding from the outer peripheral surface of the enlarged diameter cylindrical portion 13 is maximized at the small diameter cylindrical portion side end P <b> 1, and is inserted into the through hole H of the vehicle body panel P. By changing the position at the contact point P3 with the inner surface Ha of the through hole, the projecting height gradually decreases from the small-diameter cylindrical portion side end P1 toward the contact point P3, and from the contact point P3, The amount of protrusion toward the point P2 reaching the second wall 14c is substantially constant. In addition, a circumferential groove 25 is provided at a position close to the second wall 14c, so that the second wall 14c at the tip of the inclined wall can easily fall into the vehicle body locking recess 14.
Further, a groove 27 is provided between the end of the protruding step portion 20 on the side of the small diameter cylindrical portion 11 and the outer peripheral surface of the small diameter cylindrical portion 11 to enhance the flexibility of the small diameter cylindrical portion 11.

  The width W of each protrusion step portion 20 is the same in the axial direction X, and extends radially from the small-diameter cylindrical portion 11 side toward the vehicle body locking recess 14. The end portions 20b of the ridge step portions 20 on the small-diameter cylindrical portion 11 side are densely arranged in a state where adjacent ridge step portions are in contact with each other. A triangular recess 26 made of the outer peripheral surface 13a of the enlarged diameter cylindrical portion 13 is provided in a direction extending from the small diameter side to the large diameter side.

  A central groove 22 in the axial direction is provided at the center in the circumferential direction of the recess 26. Further, both side grooves 23 are provided along the base portion of the protruding step portion 20. Even if the ridge step portion 20 is projected by the grooves 22 and 23 to increase the rigidity of the diameter-expanded cylindrical portion 13, it can be easily bent in the diameter-reducing direction when inserted into the through hole of the vehicle body panel. I have to. That is, the grooves 22 and 23 guide the dent 26 in the direction in which it is folded to reduce the diameter without difficulty.

  A thin-walled end surface portion 29 is provided at the large-diameter end of the large-diameter cylindrical portion 13, and a divided small-diameter cylindrical portion 19 divided by a slit 29 a protrudes from the center of the end surface portion 29.

  Next, a method of attaching the grommet 10 to the wire harness W / H and mounting it in the through hole H of the vehicle body panel P formed of a dash panel that partitions the engine room side (X) and the indoor side (Y) will be described.

  The small diameter cylindrical portion 11 is pushed into the through hole H from the engine room side (X). At this time, as shown in FIG. 5A, the central axis S1 of the grommet 10 coincides with the central axis S0 of the through hole H, and the grommet 3 is straight when the insertion posture of the grommet 10 is straight. As shown in FIG. 5 (B), the operator recognizes that the dimension L between the ribs 21 for confirming the center position and the through hole H is substantially the same, and the grommet 10 is in a straight insertion posture. Can be judged.

On the other hand, when the central axis S1 of the grommet 10 does not coincide with the central axis S0 of the through hole H as shown in FIG. 6A and is inclined S3, as shown in FIG. The operator can determine at a glance that the dimension L between the rib 21 for position confirmation and the through hole H includes a narrow L2 and a wide L3, and the grommet 10 is in an oblique insertion posture.
Therefore, the insertion posture can be corrected immediately after insertion so that the dimension L between the rib 21 and the through hole H is the same. By inserting the rib 21 and the through hole H with care so that the dimensions of the rib 21 and the through hole H are the same, the insertion can be performed while the insertion posture is not inclined and the insertion posture is straight.

  Moreover, since a large number of protruding step portions 20 are provided on the outer peripheral surface of the thin-walled enlarged-diameter cylindrical portion 13, the rigidity of the enlarged-diameter cylindrical portion 13 increases, and when the grommet 10 is inserted obliquely, the inner peripheral surface of the through hole It is possible to reliably prevent the diameter-expanded cylindrical portion 13 at the portion in pressure contact with the bent portion from being bent.

  When the diameter-expanded cylindrical portion 13 of the grommet 10 passes through the through hole H and reaches the contact point P3 of the protruding step portion 20 that is the same as the inner diameter of the through hole H, the operator pushes the grommet 10 at a stroke from this point. Then, the protruding step 20 is passed through the through hole H so as to be crushed. At this time, since the grooves 22 and 23 are provided in the recess portion 26 between the protruding step portions 20, the recess portion 26 is smoothly reduced in diameter, and the circumferential groove 25 on the tip side is present. The second wall 14c easily falls down into the vehicle body locking recess 14, so that a large pushing force is not required and the pushing can be performed with a low insertion force.

In this manner, the protruding end of the second wall 14c passes through the through hole H while pressing the outer surface 20a of the eight protruding stepped portions 20 with the inner peripheral surface of the through hole H and reducing the diameter of the enlarged diameter cylindrical portion 13. Let
When the second wall 14c passes through the through hole H, the second wall 14c is elastically returned to the initial position, and the peripheral portion of the through hole H is dropped into the groove 14b between the second wall 14c and the first wall 14a. In this state, the opposing surfaces of the second wall 14c and the first wall 14a are in pressure contact with both surfaces of the vehicle body panel P, and are in pressure contact with the lip 14e protruding from the groove bottom surface of the inner peripheral surface of the through hole H. 10 is locked to the through hole H of the vehicle body panel P in a sealed state.

As described above, the protrusion step portion 20 is provided on the outer peripheral surface of the enlarged diameter cylindrical portion 13 of the grommet 10, and the rib for checking the center position on the small diameter tube portion side from the through hole contact position of the protrusion step portion 20. 21 is provided, the operator can correct the oblique insertion posture by looking at the dimension between the rib 21 and the through hole H.
Further, since the grooves 22 and 23 are provided so that the respective recessed portions 26 between the ridge step portions 20 are folded, the diameter is uniformly reduced in the circumferential direction, and the second wall 14c is engaged with the vehicle body by the grooves 25. Since it is easy to fall into the stop recess, the grommet 10 can be locked in the through hole of the vehicle body panel with a low insertion force.

In addition, this invention is not limited to the said embodiment, Six pieces may be sufficient as the number of protrusion steps, and ten pieces may be sufficient as it.
In addition, the split small-diameter cylindrical portion on the large-diameter side of the large-diameter cylindrical portion may be eliminated, but in consideration of the dropout after the grommet is attached to the through hole of the vehicle body panel, the split-diameter cylindrical portion is provided and the wire harness and tape It is preferable to wind and fix. Moreover, you may provide the cable insertion cylinder part for optional parts in a grommet. Furthermore, it goes without saying that the through-hole has an elliptical shape, and the expanded cylindrical portion can also be applied to a grommet having an elliptical cross section.

It is a perspective view of the grommet of an embodiment of the present invention. It is the side view seen from the small diameter cylinder part side of the said grommet. It is sectional drawing of the part which provided the protrusion step part of the said grommet. It is a principal part enlarged view which shows the rib for the center position confirmation of the said grommet. (A) (B) is explanatory drawing in the case of an insertion attitude | position with a straight grommet. (A) (B) is explanatory drawing in case a grommet is a diagonal insertion attitude | position. It is drawing which shows the conventional grommet. (A) (B) is explanatory drawing in case a grommet becomes a diagonal insertion attitude | position.

Explanation of symbols

P Car body panel H Through hole 10 Grommet 11 Small diameter cylindrical part 12 Thick end thick part 13 Large diameter cylindrical part 14 Car body locking concave part 14a First wall 14b Groove 14c Second wall 20 Projection step part 21 Center position confirmation rib 22 , 23, 24, 25, 27 groove

Claims (3)

It is made of rubber or elastomer that is engaged with a through hole of a vehicle body panel in a state where it is sheathed on an automobile wire harness, and has a small-diameter cylindrical portion, a thin-diameter cylindrical portion continuous to the small-diameter cylindrical portion, and the large-diameter cylindrical portion A distal end thick portion projecting in a direction perpendicular to the axis continuous with the distal end of the large diameter side, and a vehicle body locking recess provided annularly on the outer peripheral surface between the thick portion of the distal end and the enlarged diameter cylindrical portion, A grommet that is inserted into the through-hole from the small-diameter cylindrical portion side and locks the vehicle body locking recess to the vehicle body panel,
A plurality of ridge step portions extending in the axial direction from the small diameter tube portion to the vehicle body locking recess are provided at intervals in the circumferential direction on the outer peripheral surface of the enlarged diameter tube portion, and an outer surface of the ridge step portion is provided. A grommet characterized in that center position confirmation ribs are provided concentrically on the outer surface of each protrusion step at a position where a virtual outer diameter D1 to be connected is smaller than an inner diameter d of the through hole of the vehicle body panel.   The rib for checking the center position is provided on the entire circumferential length of the outer surface of the protruding stepped portion, and the height thereof is such that the virtual outer diameter D1 connecting the tips of the ribs of each protruding stepped portion is larger than the inner diameter d of the through hole. The grommet according to claim 1, wherein the grommet is set to be small. The vehicle body locking recess has a high first wall on the side of the thick part at the tip and a low second wall on the side of the enlarged diameter cylindrical part with the groove bottom interposed therebetween, and the second wall is bent inward to pass through the through hole. A shape to be made, and
There are six or more protruding stepped portions provided on the outer peripheral surface of the diameter-enlarging cylindrical portion, projecting from the continuous end with the small-diameter cylindrical portion, and extending to the projecting end of the second wall of the vehicle body locking recess. The circumferential width of the stepped portion extends in the axial direction as the same,
Projecting amount of the projecting step portion, when inserting the central axis line S1 of the grommet in the orientation coincides with the center SO of the through hole of the body panel to said through hole, the contact point between the inner surface of the through hole the portion up to a position gradually thinned small diameter cylinder portion side end as the maximum protruding amount, the second wall to the tip protrusion amount of the said vehicle body latch recess is bent at the contact point and a fixed, reaches the second wall The grommet according to claim 1 or 2, wherein a circumferential groove is provided at a position near the tip.

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