JP6998816B2 - Grommet - Google Patents

Description

The present invention relates to a grommet that is attached to a panel such as a dash panel of an automobile to protect or waterproof a wire harness that penetrates the panel.

Since the grommet is attached to the panel while protecting the wire harness penetrating the panel, as disclosed in Patent Document 1 below, the tube portion for inserting and holding the wire harness and the fitting for attachment to the panel. It is a structure that has a joint part integrally.

The tubular portion has a length required to hold the wire harness, and a fitting collar portion is formed in the intermediate portion in the longitudinal direction of the tubular portion. The fitting flange portion projects to the outer periphery and is fitted into a through-state mounting hole formed in the panel to be mounted.

In order to fit and fix the fitting flange to the mounting hole, the fitting flange has a constricted fitting groove that fits into the mounting hole in the middle of the fitting flange in the direction corresponding to the longitudinal direction of the cylinder. There is. A fitting step portion that projects to the outer periphery from the fitting groove portion and a tapered surface having a smaller diameter toward the mounting tip side are formed in order on the portion on the mounting tip side of the fitting groove portion. On the other hand, a receiving portion that is larger than the fitting step portion and projects to the outer periphery is formed in the portion on the rear end side of the fitting portion. An annular deformed concave groove is formed between the receiving portion and the tubular portion located on the inner peripheral side of the receiving portion so as to enter toward the back side of the tapered surface toward the mounting tip direction, and when the grommet is mounted on the mounting hole, the grommet is mounted. It enables the deformation of the fitting step.

Since the fitting collar must maintain a stable and strong mounting state without accidental dropping from the panel or displacement, the fitting collar is required to have strength. For this reason, the thick part has been formed solidly so far.

Japanese Patent No. 5794962

The main object of the present invention is to make it possible to reduce the weight while ensuring the required mounting strength.

The means for this is a tubular portion for inserting and holding the wire harness, and a through-state mounting hole formed in a panel formed in a larger diameter than the tubular portion in the intermediate portion in the longitudinal direction of the tubular portion and to be mounted. A grommet having a fitting collar that is fitted into the fitting collar, and a moat-shaped concave groove formed in a portion on the outer peripheral side of the tubular portion on the mounting tip side and the concave groove are formed in the fitting collar. A plurality of ribs for connecting the inner peripheral wall and the outer peripheral wall to the inside and outside are provided, and as the rib, the portion near the outer peripheral wall is closer to the inner peripheral wall than the portion closer to the inner peripheral wall. It is a grommet having a pair of inclined ribs inclined in a direction approaching each other with respect to a virtual reference line extending in the radial direction to the outer periphery of the grommet.

In this configuration, the concave groove of the fitting collar contributes to the weight reduction of the grommet as compared with the case of the solid structure, and when the wire harness is inserted into the cylinder, it is fitted with the cylinder. Allows deformation of the inner peripheral wall of the collar to spread to the outer peripheral side. At the time of this deformation, a pair of inclined ribs forming a substantially trapezoidal shape in front view bend to elastically support the load. In the mounting state with respect to the mounting hole, when an external force is applied due to gravity, vibration, tension, etc. and a load is applied from the outer peripheral side, a pair of inclined ribs that are tilted narrowly toward the outer peripheral wall tilt in a direction close to each other. While generating compressive stress, it elastically supports the load. In addition, the concave groove of the fitting collar reduces the load generated on the grommet due to gravity and vibration by reducing the weight.

As an aspect of the present invention, the inner peripheral wall forming the concave groove may be formed in the tubular portion, and the outer peripheral wall forming the concave groove may be formed in the fitting collar portion.

With this configuration, it is possible to increase the radial distance in the concave groove, which contributes to weight reduction.

As an aspect of the present invention, the pair of inclined ribs may have the same inclination angle with respect to the reference line to form an isosceles trapezoidal shape in front view.
In this configuration, a pair of inclined ribs having the same inclination angle with respect to the reference line can stably support the load applied from the outer peripheral side.

As an aspect of the present invention, the pair of inclined ribs may be evenly arranged along the circumferential direction of the concave groove.
In this configuration, the pair of inclined ribs evenly arranged in the circumferential direction of the concave groove can support the load applied from the outer peripheral side in a well-balanced manner regardless of the applied portion.

As an aspect of the present invention, the distance between the portions of the pair of inclined ribs that are in contact with the inner peripheral wall may be set wider than the distance between the pair of inclined ribs that are adjacent to each other and that are in contact with the inner peripheral wall.
In this configuration, the pair of inclined rib portions, which are wider than the distance between the pair of inclined ribs in contact with the inner peripheral wall, secure a portion that allows displacement from the inner peripheral side to the outer peripheral side, and the load from the outer peripheral side is secured. Good support.

As an aspect of the present invention, as the rib, a radial rib extending along the radial direction can be formed between the pair of inclined ribs adjacent to each other.
In this configuration, the radial ribs elastically support the load applied from the outer peripheral side between the pair of inclined ribs by compressive stress or bending stress, and suppress the deformation between the pair of inclined ribs.

When the radial ribs are provided, the number of the pair of inclined ribs and the radial ribs may be the same.
In this configuration, a pair of inclined ribs and radial ribs provided in the same number can act differently at adjacent positions to achieve uniform support as a whole.

When the radial ribs are provided, the thickness of the radial ribs can be made thicker than the thickness of the pair of inclined ribs.
In this configuration, the radial ribs between a pair of inclined ribs adjacent to each other, which are spaced closer to the outer peripheral side, have a thickness larger than that of the pair of inclined ribs to ensure the required strength and are more effective. Enables meaningful weight reduction.

When the radial ribs are provided, the area of the portion surrounded by the pair of inclined ribs can be further set to be larger than the area of the portion surrounded by the pair of inclined ribs and the radial ribs adjacent to each other.
In this configuration, the size of the space of the substantially trapezoidal portion in the pair of tilted ribs is larger than the size of the substantially triangular partial space between the pair of adjacent tilted ribs and the radial ribs, so that the pair of tilted ribs is tilted. By avoiding the ribs becoming narrower in the circumferential direction of the concave groove and the inclination with respect to the reference line being too gentle, the pair of inclined ribs can be utilized to achieve both strength assurance and weight reduction.

As an aspect of the present invention, all the ribs are arranged symmetrically with respect to the center line on a plurality of virtual diameter lines extending in the radial direction of the fitting flange portion through the center line of the cylinder portion. , At least one of the diameter lines can be an axis of symmetry in which the ribs are arranged line-symmetrically.
In this configuration, the ribs symmetrically arranged on the virtual diameter line are stretched in the radial direction to strongly maintain the mounted state.

As an aspect of the present invention, the rib can be extended to the bottom of the concave groove.
In this configuration, the ribs transfer the load to the bottom of the groove and provide firm support.

As an aspect of the present invention, the thickness of the portion of the rib on the inner peripheral wall side can be formed to be thicker than the thickness of the portion on the outer peripheral wall side.
In this configuration, the part on the inner peripheral wall side, which can be said to be the root of the rib, is thicker than the part on the outer peripheral wall side, which can be said to be the tip, and it strongly supports the load applied from the outer peripheral side, which is effective while reducing the weight. Achieve support.

As an aspect of the present invention, an annular deformed concave groove is formed in the fitting flange portion on the mounting rear end side opposite to the mounting tip side, on the outer peripheral side of the tubular portion, toward the mounting tip direction. The deformed concave groove and the concave groove are adjacent to each other across the outer peripheral wall, and the bottom of the concave groove is formed into a tapered shape extending in an inclined manner toward the tubular portion so that the outer peripheral wall has a conical shape. It can be a formed grommet.
In this configuration, the conical outer peripheral wall facilitates deformation of the tubular portion toward the outer peripheral side.

As an aspect of the present invention, the tubular portion has one large diameter portion in the longitudinal direction and the other small diameter portion in the longitudinal direction, and the large diameter portion is formed on the mounting tip side on the inner peripheral surface of the tubular portion. A conical surface is formed between the large-diameter portion and the small-diameter portion, and the tip of the bottom of the concave groove is formed at a position on the small-diameter portion side of the boundary position between the conical surface and the large-diameter portion. Can be a grommet.
In this configuration, the bottom of the concave groove formed deeper than the boundary position between the conical surface and the large diameter portion increases the susceptibility to deformation toward the outer peripheral side of the tubular portion.

According to the present invention, it is possible to secure the required mounting strength and reduce the weight at the same time.

A perspective view showing the mounting tip side of the grommet. A partial cross-sectional side view showing the usage mode of the grommet. A perspective view showing the rear end side of the grommet mounting. Front view showing the surface on the mounting tip side of the grommet. FIG. 4A is a cross-sectional view taken along the line AA of FIG. BB sectional view of FIG. A perspective view of the grommet in a half-split state. Explanatory drawing showing a groove and a rib. Explanatory drawing which shows other example of a rib shape. Explanatory drawing which shows the working state. Stress analysis diagram.

An embodiment for carrying out the present invention will be described below with reference to the drawings.

FIG. 1 shows a perspective view of the grommet 11 attached and viewed from the tip side. The grommet 11 is made of rubber or synthetic resin, and is fixed to a wire harness 25 penetrating a panel 21 such as a panel dash panel of an automobile as shown in FIG. 2, and the wire harness 25 is attached to the panel 21. .. In FIG. 2, the upper half shows the cross section and the lower half shows the side surface. For mounting on the panel 21, either push the mounting tip side of the grommet 11 integrated with the wire harness 25 toward the penetrating mounting hole 22 formed in the panel 21 (see the white arrow F1 in FIG. 2). ), The mounting tip side of the grommet 11 is pulled from the opposite side of the mounting hole 22 (see the white arrow F2 in FIG. 2).

Such a grommet 11 projects to the outer periphery at the middle portion between the tubular portion 13 that inserts and holds the wire harness 25 and the tubular portion 13 in the longitudinal direction, in other words, is formed to have a diameter larger than that of the tubular portion 13 and is formed on the panel 21. A fitting flange portion 15 to be fitted into the mounting hole 22 of the above is integrally provided.

The tubular portion 13 is formed to have a length required to integrally hold the wire harness 25. After the wire harness 25 is inserted into the tubular portion 13, the adhesive tape (not shown) is wrapped around both ends of the tubular portion 13 to fix the wire harness 25, but the entire tubular portion 13 is the same as the thickness of the wire harness 25. If the thickness is large, it is difficult to insert the enlarged diameter portion of the diameter-expanding tool (not shown) when inserting the wire harness 25, so that the tubular portion 13 is larger than the thickness of the wire harness 25 in one of the longitudinal directions. It has a large diameter portion 31 and a small diameter portion 32 corresponding to the thickness of the wire harness 25 on the other side in the longitudinal direction.

In the grommet 11 of the illustrated example, the large diameter portion 31 is formed on the mounting tip side. Since the large diameter portion 31 is thicker than the thickness of the wire harness 25 that is inserted and held, two notched portions 33 that are cut along the longitudinal direction from the end portion are formed at positions facing each other. This is to enable fixing with adhesive tape. That is, by dividing the large diameter portion 31 of the tubular portion 13 by the notch portion 33, the adhesive tape can be wound around the wire harness 25 step by step. Specifically, the one-sided portion 31a of the large-diameter portion 31 divided by the notch 33 is fixed to the wire harness 25, and then the other-side portion 31b of the large-diameter portion 31 divided by the notch 33 is fixed. Is fixed to the previously integrated wire harness 25 and the portion 31a on one side of the large diameter portion 31.

A conical surface 34 is formed between the large diameter portion 31 and the small diameter portion 32 on the inner peripheral surface of the tubular portion 13. The inclination angle of the conical surface 34 is, for example, the longitudinal length of the tubular portion 13 so that the desired deformability can be obtained in consideration of the length of the transition portion from the small diameter portion 32 to the large diameter portion 31 in the longitudinal direction of the tubular portion 13. The angle is set to about 40 ° to 55 ° with respect to the direction.

The fitting flange portion 15 has a constricted fitting groove portion 51 that fits into the mounting hole 22 in the middle portion in the direction corresponding to the longitudinal direction of the tubular portion 13 in order to fix the fitting flange portion 15 to the mounting hole 22 forming a circle. ing. In the portion on the mounting tip side of the fitting groove portion 51, a fitting step portion 52 projecting to the outer periphery from the fitting groove portion 51 and a tapered surface 53 having a smaller diameter toward the mounting tip side are sequentially provided from the fitting groove portion 51 side. It is formed. A plurality of ridges 54 extending along the longitudinal direction and the corresponding direction of the tubular portion 13 are evenly provided on the outer surfaces of the fitting step portion 52 and the tapered surface 53 over the entire circumference, and are provided at the time of mounting to the mounting hole 22. We are trying to reduce contact resistance. On the mounting tip side of the tapered surface 53, a tip surface portion 55 having a circular diameter smaller than that of the mounting hole 22 is formed.

A receiving portion 56 having an annular diameter larger than that of the fitting step portion 52 is formed on the mounting rear end side of the fitting flange portion 15 with respect to the fitting groove portion 51, that is, the portion opposite to the mounting tip side. ing. The receiving portion 56 has a solid structure having a desired rigidity, and has a lip portion 56a on the outer peripheral edge that extends diagonally toward the mounting tip side.

FIG. 2 shows a portion of the fitting flange portion 15 on the surface on the rear end side of the fitting portion on the outer peripheral side of the tubular portion 13, that is, between the receiving portion 56 and the tubular portion 13 located on the inner peripheral side of the receiving portion 56. As shown in FIG. 3, an annular deformed concave groove 57 that enters toward the mounting tip is formed. The deformed concave groove 57 has a size that extends to a portion extending to the back side of the fitting step portion 52 and the tapered surface 53, and the portion of the fitting step portion 52 that overhangs the outermost side is directed outward in the radial direction. The thin-walled portion 52a is formed by the inverted V-shaped notch 57a.

FIG. 3 shows a perspective view of the grommet 11 attached and viewed from the rear end side. Since the conical surface 34 is formed on the inner peripheral surface of the tubular portion 13 as described above, the inner peripheral side surface 58 of the deformed concave groove 57 is located on the back side of the conical surface 34 and corresponds to the conical surface 34. , Is formed in a substantially conical shape.

By forming the deformed concave groove 57, the fitting step portion 52 is allowed to be deformed when the grommet 11 is mounted on the mounting hole 22, and the weight of the grommet 11 is reduced.

As shown in FIGS. 1 and 2, a moat-shaped concave groove 61 is formed in the above-mentioned tip surface portion 55 of the fitting flange portion 15, that is, a portion on the outer peripheral side of the cylinder portion 13 of the surface on the mounting tip side. , Weight reduction is done.

The concave groove 61 is formed between the outer circumference of the tubular portion 13 and the inner circumference of the fitting flange portion 15. That is, the inner peripheral wall 63 forming the concave groove 61 is formed in the tubular portion 13, and the outer peripheral wall 64 forming the concave groove 61 is formed in the fitting flange portion 15. In the example shown in FIG. 2, the step portion 63a having a diameter larger than the outer peripheral surface position of the large diameter portion 31 of the cylinder portion 13 is provided, but here, this step portion 63a is also a part of the cylinder portion 13. Suppose that

The boundary between the cylinder portion 13 and the fitting flange portion 15 is not always clearly distinguishable, and the concave groove 61 is formed between the outer periphery of the cylinder portion 13 and the inner circumference of the fitting flange portion 15 as described above. In addition to being formed, it may be formed only on the fitting flange portion 15.

The concave groove 61 is provided with a rib 62, that is, a plurality of ribs 62 for connecting the inner peripheral wall 63 forming the concave groove 61 and the outer peripheral wall 64 inside and outside.

FIG. 4 shows a surface of the grommet 11 on the mounting tip side, FIG. 5 is a cross-sectional view taken along the line AA of FIG. 4, that is, a cross-sectional view cut at a position passing through the center of the rib 62, and FIG. -B cross-sectional view, that is, a cross-sectional view cut at a position passing between the ribs 62. Further, FIG. 7 is a perspective view cut at a position passing between the ribs 62.

As shown in these figures, the deformed concave groove 57 as described above is formed on the mounting rear end side of the fitting flange portion 15, and the deformed concave groove 57 has a conical inner peripheral side surface 58. Since the concave groove 61 is provided, the concave groove 61 is adjacent to the deformed concave groove 57 across the outer peripheral wall 64 forming the concave groove 61, and the bottom of the concave groove 61 is directed toward the small diameter portion 32 of the tubular portion 13. It has a tapered shape that extends in an inclined manner, and the outer peripheral wall 64 has a conical shape. That is, the cross-sectional shape of the concave groove 61 is a substantially triangular shape or a substantially fan shape. A conical wall 65 is continuously provided over the small diameter portion 32 on the extension line in the inner peripheral direction of the outer peripheral wall 64, and the inner surface of the conical wall 65 becomes the conical surface 34 of the tubular portion 13 described above.

As shown in FIGS. 6 and 7, the tip end 61a of the bottom of the concave groove 61 is formed at a position closer to the small diameter portion 32 than the boundary position 34a between the conical surface 34 and the large diameter portion 31. In other words, the concave groove 61 is formed to a deeper position.

As the rib 62 described above, as shown in FIG. 4, two types of ribs 62, a pair of inclined ribs 66 and a radial rib 67 formed between a pair of inclined ribs 66 adjacent to each other, are used. It has more than one. The pair of inclined ribs 66 and the radial ribs 67 are evenly arranged along the circumferential direction of the concave groove 61, and the number of the pair of inclined ribs 66 and the radial ribs 67 is the same. Specifically, the pair of inclined ribs 66 and the radial ribs 67 are four each, and the ribs 62 of the same type are arranged at 90 ° intervals.

In FIG. 8, for the sake of clarity, the thin line showing the three-dimensional shape of the surface shown in FIG. 4 is removed, and the surface on the mounting tip side of the grommet 11 is simplified and drawn. A pair of inclined ribs 66 and radial ribs 67 will be described with reference to this figure.

The pair of inclined ribs 66 are composed of two inclined rib carriers 66a, and the inclined rib carrier 66a has a fitting flange from the center line C of the tubular portion 13 rather than a portion closer to the outer peripheral wall 64 than a portion closer to the inner peripheral wall 63. It is inclined in a direction approaching each other with respect to a virtual reference line D extending radially toward the outer periphery of the portion 15. The tilt angle α of the pair of tilt ribs 66 with respect to the reference line D is the same. Further, the thickness of the inclined rib carrier 66a from the portion closer to the inner peripheral wall 63 to the portion closer to the outer peripheral wall 64 is uniform.

The inclination angle α of the inclined rib carrier 66a is appropriately set according to conditions such as the distance between the inner peripheral wall 63 forming the concave groove 61 and the outer peripheral wall 64 and the diameters of the inner peripheral wall 63 and the outer peripheral wall 64. For example, it is advisable to set the inclination to about 15 ° to 20 ° with respect to the reference line D.

In the illustrated example, the inclined rib carriers 66a constituting the pair of inclined ribs 66 do not touch each other, but are separated from each other not only at the portion in contact with the inner peripheral wall 63 but also at the portion in contact with the outer peripheral wall 64. Therefore, the portion partitioned by the pair of inclined ribs 66, the inner peripheral wall 63, and the outer peripheral wall 64 has a substantially isosceles trapezoidal shape when viewed from the front.

Further, in the arrangement interval of the pair of inclined ribs 66 to be arranged, the interval a of the portion of the pair of inclined ribs 66 in contact with the inner peripheral wall 63 is in contact with the inner peripheral wall 63 of the pair of inclined ribs 66 adjacent to each other. It is set so as to be wider than the interval b of the portions, that is, a> b. Here, the reference position indicating the interval is an intermediate position in the width direction of the inclined rib carrier 66a, that is, a center line position of the inclined rib carrier 66a.

The radial rib 67 extends linearly along the radial direction. The thickness of the radial rib 67 from the portion closer to the inner peripheral wall 63 to the portion closer to the outer peripheral wall 64 is uniform. Further, the forming position of the radial rib 67 is set to an intermediate position between a pair of inclined ribs 66 adjacent to each other.

As described above, the pair of inclined ribs 66 and the radial ribs 67 are evenly arranged along the circumferential direction of the concave groove 61, and the number of the pair of inclined ribs 66 and the radial ribs 67 is the same. From a specific point of view, all the ribs 62, that is, the pair of inclined ribs 66 and the radial ribs 67 are on a plurality of virtual diameter lines E extending in the radial direction of the fitting flange portion 15 through the center line C of the tubular portion 13. In addition, at least one of the diameter lines E is arranged symmetrically with respect to the center line C, and is an axis of symmetry in which the ribs 62 are arranged line-symmetrically. "Arranged symmetrically" means an arrangement that is axisymmetric with a line that passes through the center line C on the virtual diameter line E and is orthogonal to the virtual diameter line E as the axis of symmetry, and is a pair of inclined ribs. The 66s face each other on the virtual diameter line E with the center line C as the boundary, and the radial ribs 67 face each other on the virtual diameter line E with the center line C as the boundary.

Since the radial rib 67 is not inclined unlike the pair of inclined ribs 66, the portion partitioned by the pair of inclined ribs 66 adjacent to each other, the radial rib 67, the inner peripheral wall 63, and the outer peripheral wall 64 is viewed from the front. It becomes a substantially triangular shape or a substantially trapezoidal shape close to a triangle.

The area S1 of the portion partitioned by the pair of inclined ribs 66, the inner peripheral wall 63, and the outer peripheral wall 64, and the area S2 of the portion partitioned by the pair of inclined ribs 66, the radial rib 67, the inner peripheral wall 63, and the outer peripheral wall 64. From the viewpoint, the former area S1, that is, the area S1 of the portion surrounded by the pair of inclined ribs 66 is the area S2 of the latter, that is, the area of the portion surrounded by the pair of inclined ribs 66 and the radial ribs 67 adjacent to each other. It is larger than S2 and is set to S1> S2. In other words, the space of the portion partitioned by the pair of inclined ribs 66, the inner peripheral wall 63, and the outer peripheral wall 64 is the portion of the portion partitioned by the pair of inclined ribs 66, the radial ribs 67, the inner peripheral wall 63, and the outer peripheral wall 64. Larger than space.

Further, all the ribs 62 do not partially connect the inner peripheral wall 63 and the outer peripheral wall 64, but the ribs 62 extend to the bottom of the concave groove 61 formed by the inner peripheral wall 63 and the outer peripheral wall 64. The hollow space 61b of the concave groove 61 divided into a plurality of parts by the rib 62 has a completely independent structure that does not communicate with each other via the rib 62.

The thickness of the pair of inclined ribs 66 and the radial rib 67 is appropriately set in consideration of weight reduction and strength, but in the relationship between the two types of ribs (the pair of inclined ribs 66 and the radial rib 67), the diameter is set. It is preferable that the thickness t1 of the directional ribs 67 is equal to or greater than the thickness t2 of the pair of inclined ribs 66, or the thickness t2 of the pair of inclined ribs 66 is equal to or less than the thickness t1 of the radial ribs 67. That is, t1 ≧ t2, and in the examples shown in FIGS. 1 and 4, the thickness of the pair of inclined ribs 66 and the radial ribs 67 are the same, but as shown in FIG. 9A. The radial rib 67 can also be made thicker.

Further, in the example shown in FIGS. 1 and 4, the thickness of the rib 62 was set to be uniform in the portion on the inner peripheral wall 63 side and the portion on the outer peripheral wall 64 side, but it is shown in FIG. 9 (b). As described above, the thickness t3 of the portion of the rib 62 on the inner peripheral wall 63 side can be formed to be thicker than the thickness t4 of the portion on the outer peripheral wall 64 side, that is, t3> t4.

In the grommet 11 configured as described above, after the wire harness 25 is inserted and held in the tubular portion 13, the fitting flange portion 15 is fitted into the mounting hole 22 of the panel 21.

First, when the wire harness 25 is inserted and held in the tubular portion 13, a diameter-expanding tool is inserted into the large-diameter portion 31 to expand the diameter of the tubular portion 13. At this time, the tubular portion 13 itself can be expanded and deformed, and the concave groove 61 is formed in the fitting flange portion 15 existing so as to project from the tubular portion 13 to the outer peripheral side. Allows the diameter expansion deformation of the tubular portion 13. Moreover, since the pair of inclined ribs 66 are inclined so as to be recessed toward the outer peripheral side, the portion in contact with the inner peripheral wall 63, which is also the portion forming the tubular portion 13, can be widely taken in the portion not in contact with the inclined rib carrier 66a. , The diameter expansion and deformation can be done relatively freely. Therefore, it is easy to insert the wire harness 25 into the tubular portion 13.

After inserting the wire harness 25 through the tubular portion 13, an adhesive tape is wrapped around the tubular portion 13 to integrate the wire harness 25 with the tubular portion 13. At this time, in the large diameter portion 31, one of the one-sided portion 31a and the other-sided portion 31b divided by the notch 33 is first fixed to the wire harness 25, and then the remaining portions are integrated first. Fix it to the converted part. Since the fixing is performed in this way, the fixing balance becomes poor depending on the work method, and the vicinity of the tip surface portion 55 of the fitting flange portion 15 and the positional relationship between the fitting flange portion 15 and the wire harness 25 are distorted. Although there is a risk, even in the unlikely event that distortion occurs, the pair of evenly arranged inclined ribs 66 and radial ribs 67 cooperate with the hollow space 61b to absorb the strain.

When the wire harness 25 is fixed, it is integrated with the wire harness 25, and the positional relationship between the tubular portion 13 and the fitting flange portion 15 is firmly maintained. Therefore, when fitting the fitting flange portion 15 into the mounting hole 22 of the panel 21, even if the fitting flange portion 15 is pressed against the mounting hole 22 by holding the wire harness 25 or the grommet 11, the fitting flange portion 15 is mounted. Even when the wire harness 25 or the grommet 11 is pulled and fitted from the opposite side of the hole 22, the pressing force or the tensile force applied to the wire harness 25 or the grommet 11 is satisfactorily transmitted to the fitting flange portion 15. Therefore, the desired fitting of the fitting flange portion 15 to the mounting hole 22 can be reliably performed.

In the state where the fitting flange portion 15 is fitted into the mounting hole 22, the fitting flange portion 15 has a concave groove 61, but the pair of inclined ribs 66 and the radial ribs 67 formed in the concave groove 61 have the fitting flange. Since the deformation of the portion 15 is suppressed, the fitted state with respect to the mounting hole 22 is firmly maintained, and unexpected dropout and displacement can be prevented.

Specifically, as shown in FIG. 10A, a pair of inclined ribs is applied when a load is applied to the fitting flange portion 15 from the outer peripheral side due to gravity, vibration, pulling of the wire harness 25, or the like. When a force acts from the direction of the center line of the 66, the inclined rib carriers 66a of the pair of inclined ribs 66 receive a load in the direction of tilting inward approaching each other and resist mainly by compressive stress, so that the fitting flange portion 15 Suppress deformation. When a force is applied from a direction deviated from the center line of the pair of inclined ribs 66, the inclined rib carriers 66a constituting the pair of inclined ribs 66 resist each other by compressive stress and bending stress, and the fitting flange portion 15 Suppress deformation.

When a load is applied to the fitting flange portion 15 from the outer peripheral side and a force is applied from the center line direction of the radial rib 67, the radial rib 67 resists by compressive stress and the fitting flange portion 15 Suppress deformation. When a force is applied from a direction deviated from the center line of the radial rib 67, it resists by bending stress and suppresses deformation of the fitting flange portion 15.

In any of these cases, it goes without saying that the pair of inclined ribs 66 or radial ribs 67 located adjacent to each other also resist the load at the same time.

Since such an action is performed, unexpected deformation of the fitting flange portion 15 of the grommet 11 is suppressed, and the mounting state with respect to the mounting hole 22 can be maintained even when gravity, vibration, or tensile force is applied.

On the other hand, when a load is applied to the wire harness 25 that has been inserted and held and a force that causes a relative displacement between the tubular portion 13 and the fitting flange portion 15 acts on the tubular portion 13, the wire harness 25 with respect to the tubular portion 13 described above is used. Since it can be flexibly deformed from the inside to the outer peripheral side as in the case of the insertion work, it is possible to absorb the strain due to the load applied from the inside as shown in FIG. 10 (b). That is, even if a load is applied from the inside toward the outer circumference, the strain due to the load is not transmitted to the outer peripheral portion. Therefore, from this point as well, the deformation of the fitting flange portion 15 is suppressed and the mounting state with respect to the mounting hole 22 is maintained. can.

The concave groove 61 of the fitting flange portion 15 together with the deformed concave groove 57 formed on the opposite side of the concave groove 61 reduces the weight of the grommet 11. In particular, since the inner peripheral wall 63 forming the concave groove 61 is formed in the tubular portion 13 and the outer peripheral wall 64 forming the concave groove 61 is formed in the fitting flange portion 15, the radial distance in the concave groove 61 is increased. By taking it, it can be made lighter. This weight reduction also reduces the load on the grommet 11 due to gravity and vibration, so that not only the weight reduction by lightening but also the mounting strength can be improved, which is a synergistic effect.

Further, since the inner peripheral wall 63 forming the concave groove 61 has a stepped portion 63a while reducing the weight, it is possible to give the portion having the fitting flange portion 15 the necessary rigidity.

As described above, in the grommet 11 having the above-mentioned configuration, it is possible to secure the required mounting strength and reduce the weight at the same time.

In particular, since the distance a of the portion of the pair of inclined ribs 66 in contact with the inner peripheral wall 63 is wider than the distance b of the portion of the pair of inclined ribs 66 adjacent to each other in contact with the inner peripheral wall 63, from the inner peripheral side to the outer peripheral side. Since the load from the outer peripheral side is well supported while securing the portion that allows the displacement of the above-mentioned, the effect of being strong against the above-mentioned pressure from the outside and being flexible to spread from the inside can be enhanced.

The effect of being flexible to spread from the inside is that the bottom of the concave groove 61 is inclined and extends toward the tubular portion 13, and the outer peripheral wall 64 and the conical wall 65 are conical, and the concave groove is formed. The tip 61a at the bottom of 61 is formed at a position closer to the small diameter portion 32 than the boundary position 34a between the conical surface 34 of the tubular portion 13 and the large diameter portion 31. That is, as compared with the case where the bottom of the concave groove 61 is a plane extending in a direction orthogonal to the longitudinal direction of the tubular portion 13, it can be flexibly deformed because it has a conical shape.

Further, since the inclination angle α of the pair of inclined ribs 66 with respect to the reference line D is the same, the load applied from the outer peripheral side can be supported with good stability.

Moreover, since the pair of inclined ribs 66 and the radial ribs 67 are evenly arranged in the same number along the circumferential direction of the concave groove 61, the load applied from the outer peripheral side can be applied from this point regardless of the portion to be applied. It is possible to suppress deformation by effectively supporting it in a well-balanced manner and uniformly as a whole.

Moreover, all the ribs 62 are arranged symmetrically with respect to the center line C on a plurality of virtual diameter lines E extending in the radial direction of the fitting flange portion 15 through the center line C of the tubular portion 13. Therefore, the ribs 62 symmetrically arranged on the virtual diameter line E are stretched in the radial direction. Therefore, the attached state can be strongly maintained.

Further, in addition to the pair of inclined ribs 66, a radial rib 67 extending in the radial direction between the pair of inclined ribs 66 is provided, and the radial rib 67 has a compressive stress with respect to a load applied from the outer peripheral side. Since it is elastically supported against the bending stress, it assists the action of the pair of inclined ribs 66 having different actions, and also cooperates with the pair of inclined ribs 66 to deform the fitting flange portion 15. Since it is suppressed, the deformation suppressing effect is high.

In addition, since the area S1 of the portion surrounded by the pair of inclined ribs 66 is set to be larger than the area S2 of the portion surrounded by the pair of inclined ribs 66 and the radial ribs 67 adjacent to each other, the pair of inclined ribs The form of 66 does not become narrow in the circumferential direction of the concave groove 61 or the inclination with respect to the reference line D is not too gentle, and the pair of inclined ribs 66 can be utilized to achieve both strength assurance and weight reduction. can.

As shown in FIG. 9A, when the thickness t1 of the radial ribs 67 is equal to or larger than the thickness t2 of the pair of inclined ribs 66, the radial direction between the pair of inclined ribs 66 having a space closer to the outer peripheral side. Since the rib 67 secures the required strength with a thickness larger than that of the pair of inclined ribs 66, more effective and meaningful weight reduction can be realized.

As shown in FIG. 9B, when the thickness t3 of the portion on the inner peripheral wall side of the rib 62 is formed to be equal to or larger than the thickness t4 of the portion on the outer peripheral wall side, high stress is generated due to the pressure applied. It is possible to increase the strength of the portion on the root side of the rib 62, which is easy to do. Therefore, it is possible to realize effective support while increasing the strength of the required portion and reducing the weight.

Further, since the rib 62 extends to the bottom of the concave groove 61, the rib 62 can transmit the load to the bottom of the concave groove 61 and firmly support the rib 62, so that the required mounting strength can be obtained while reducing the weight. Can be secured.

FIG. 11 shows the results of stress analysis.
FIG. 11A shows a state in which an external force acts from the center line direction of the pair of inclined ribs 66, and FIG. 11B shows a state in which an external force acts from the center line direction of the radial ribs 67. As shown in these cases, it can be seen that in any case, the load is well supported and the deformation of the outer peripheral portion of the fitting flange portion 15 is suppressed.

11 (c) and 11 (d) are comparative examples, and show a case of a structure in which eight ribs extending radially at the same volume as the grommets of the above-mentioned (a) and (b) are provided at equal intervals. There is. Since the volumes are the same, the ribs in the cases of (c) and (d) are thicker than those in the cases of (a) and (b).

As shown in FIG. 11 (c), when a load is applied from the direction of the center line of the rib, the load can be supported, but as shown in FIG. 11 (d), it corresponds to the intermediate position of the two ribs. It can be seen that when a load is applied from the direction in which the fitting flange is applied, an excessive stress is generated on the outer peripheral portion of the fitting flange portion, and the outer peripheral portion of the fitting flange portion may be deformed.

From this, it can be said that the grommet 11 of the above-mentioned (a) and (b) can suppress the deformation of the fitting flange portion 15 even if the grommet 11 has the same volume, that is, the same weight.

The above-mentioned configuration is one embodiment for carrying out the present invention, and the present invention is not limited to the above-mentioned configuration, and other configurations may be adopted.

For example, the mounting hole 22 of the panel 21 is not limited to a circular shape, and may be an elliptical shape, for example. In such a case, the ribs are not uniformly and evenly arranged, but are evenly and well-balanced according to the shape. It is good.

11 ... Grommet 13 ... Cylinder 15 ... Fitting flange 21 ... Panel 22 ... Mounting hole 25 ... Wire harness 31 ... Large diameter 32 ... Small diameter 34 ... Conical surface 57 ... Deformed concave groove 61 ... Concave groove 62 ... Rib 63 ... Inner peripheral wall 64 ... Outer peripheral wall 65 ... Conical wall 66 ... Pair of inclined ribs 67 ... Radial ribs

Claims (14)

Fitting that is fitted into a tubular portion that inserts and holds a wire harness and a through-state mounting hole that is formed in a diameter larger than that of the tubular portion in the intermediate portion in the longitudinal direction of the tubular portion and is formed in a panel to be mounted. A grommet with a collar
The fitting collar has a moat-shaped concave groove formed on the outer peripheral side of the tubular portion on the mounting tip side, and a plurality of ribs connecting the inner peripheral wall and the outer peripheral wall forming the concave groove to the inside and outside. Be prepared,
As the rib, the portion near the outer peripheral wall is closer to each other than the portion near the inner peripheral wall with respect to a virtual reference line extending in the radial direction from the center line of the tubular portion to the outer periphery of the fitting flange portion. A grommet with a pair of tilted ribs. The inner peripheral wall forming the concave groove is formed in the tubular portion, and the inner peripheral wall is formed.
The grommet according to claim 1, wherein the outer peripheral wall forming the concave groove is formed in the fitting flange portion. The grommet according to claim 1 or 2, wherein the pair of inclined ribs have the same inclination angle with respect to the reference line. The grommet according to any one of claims 1 to 3, wherein the pair of inclined ribs are evenly arranged along the circumferential direction of the concave groove. Any of claims 1 to 4, wherein the distance between the pair of inclined ribs in contact with the inner peripheral wall is set wider than the distance between the pair of inclined ribs adjacent to each other in contact with the inner peripheral wall. The grommet described in item 1. The grommet according to any one of claims 1 to 5, wherein as the rib, a radial rib extending along the radial direction is formed between the pair of inclined ribs adjacent to each other. The grommet according to claim 6, wherein the pair of inclined ribs and the radial ribs have the same number of ribs. The grommet according to claim 6 or 7, wherein the thickness of the radial rib is thicker than the thickness of the pair of inclined ribs. One of claims 6 to 8 in which the area of the portion surrounded by the pair of inclined ribs is set to be larger than the area of the portion surrounded by the pair of inclined ribs adjacent to each other and the radial ribs. The grommet described in the section. All the ribs are arranged symmetrically with respect to the center line on a plurality of virtual diameter lines extending in the radial direction of the fitting flange portion through the center line of the cylinder portion.
The grommet according to any one of claims 1 to 9, wherein at least one of the diameter lines serves as an axis of symmetry in which the ribs are arranged line-symmetrically. The grommet according to any one of claims 1 to 10, wherein all the ribs extend to the bottom of the groove. The grommet according to any one of claims 1 to 11, wherein the thickness of the portion on the inner peripheral wall side of all the ribs is formed to be thicker than the thickness of the portion on the outer peripheral wall side. An annular deformed concave groove that enters toward the mounting tip is formed on the outer peripheral side of the tubular portion on the mounting rear end side opposite to the mounting tip side in the fitting flange portion, and the deformed concave groove is formed. And the concave groove are adjacent to each other across the outer peripheral wall.
The grommet according to any one of claims 1 to 12, wherein the bottom of the concave groove is formed into a tapered shape extending in an inclined manner toward the tubular portion, and the outer peripheral wall is formed in a conical shape. The tubular portion has one large diameter portion in the longitudinal direction and the other small diameter portion in the longitudinal direction.
The large diameter portion is formed on the mounting tip side,
A conical surface is formed between the large-diameter portion and the small-diameter portion on the inner peripheral surface of the tubular portion.
The grommet according to any one of claims 1 to 13, wherein the tip of the bottom of the concave groove is formed at a position on the small diameter portion side of the boundary position between the conical surface and the large diameter portion. ..

Images