JP7463984B2 - Grommet Assembly and Wire Harness - Google Patents

Description

The present disclosure relates to a grommet assembly and a wire harness.

For example, when wiring an electric wire through a panel (body panel) that separates the inside and outside of an automobile, a through hole is provided in the panel and a grommet is attached to the through hole (see, for example, Patent Document 1). The grommet is made of, for example, resin, and protects the electric wire passing through the through hole in the panel. When attached to the panel, the grommet has a seal portion that comes into contact with the panel. The seal portion ensures waterproof performance.

JP 2020-162188 A

If a grommet is attached to a panel at an angle, a gap will form between the seal of the grommet and the panel, reducing its waterproofing performance. In addition, if the grommet is tilted due to vibration, for example, while attached to the panel, a gap will form between the seal and the panel, reducing its waterproofing performance.

The present disclosure therefore aims to provide a grommet assembly that is easy to install on a panel and that can prevent a decrease in water-stopping performance even when an external force is applied, and a wire harness that includes the grommet assembly.

A grommet assembly according to one aspect of the present disclosure is a grommet assembly that is attached to a panel having a first surface and a second surface opposite to the first surface, and a through hole penetrating from the first surface to the second surface, and includes a grommet that covers the through hole from the first surface side and has a hole through which an electric wire passes, and an annular inner member that is attached to the grommet and through which the electric wire passes on the inner peripheral side, the grommet has an annular seal portion that contacts the first surface, and the inner member has a cylindrical main body portion that is provided on the inner peripheral side of the through hole, an engagement piece that is provided on the outer peripheral side of the main body portion and engages with the panel, a guide portion that extends from the main body portion in a first direction that is a direction from the first surface side to the second surface side and has a first guide surface that can slide against the inner peripheral surface of the through hole, and a protrusion that is provided on the outer peripheral side of the main body portion and protrudes radially outward from the main body portion and can contact the inner peripheral surface of the through hole.

A wire harness according to one embodiment of the present disclosure includes an electric wire passing through a through hole provided in a panel having a first surface and a second surface opposite to the first surface, and the grommet assembly attached to the panel to protect the electric wire.

According to the present disclosure, the grommet assembly can be easily installed and the deterioration of water-stopping performance can be suppressed.

FIG. 1 is a perspective view showing a part of a wire harness according to an embodiment. FIG. 2 is a perspective view of the grommet assembly. FIG. 3 is an exploded perspective view of the grommet assembly. FIG. 4 is a cross-sectional view of the grommet assembly. FIG. 5 is an enlarged perspective view showing a portion of the grommet assembly. FIG. 6 is a cross-sectional view illustrating the installation work of the grommet assembly. FIG. 7 is a cross-sectional view illustrating the installation work of the grommet assembly. FIG. 8 is a cross-sectional view illustrating the installation work of the grommet assembly.

Overview of the embodiments of the present disclosure
Below, an overview of the embodiments of the present disclosure will be listed and described.
(1) An embodiment of a grommet assembly is a grommet assembly that is attached to a panel having a first surface and a second surface opposite to the first surface, and having a through hole that penetrates from the first surface to the second surface, the grommet comprising: a grommet that covers the through hole from the first surface side and has a hole through which an electric wire passes; and an annular inner member that is attached to the grommet and through which the electric wire passes on its inner side, the grommet having an annular sealing portion that contacts the first surface, and the inner member having a tubular main body portion provided on the inner side of the through hole, an engaging piece provided on the outer peripheral side of the main body portion and engaging with the panel, a guide portion extending from the main body portion in a first direction that is a direction from the first surface side to the second surface side, the guide portion having a first guide surface that can slide against the inner peripheral surface of the through hole, and a protrusion portion provided on the outer peripheral side of the main body portion that protrudes radially outward from the main body portion and can contact the inner peripheral surface of the through hole.

According to the grommet assembly of the embodiment, when attaching the grommet assembly to a panel, the first guide surface is brought into sliding contact with the inner peripheral surface of the through hole, and then the main body can be inserted into the through hole. The first guide surface positions the grommet assembly relative to the through hole, improving the ease of attachment.
With the grommet assembly attached to the panel, even if the grommet assembly is displaced due to, for example, vibration, the protrusion comes into contact with the inner peripheral surface of the through hole, limiting the displacement. This prevents the grommet assembly from tilting, making it difficult for a gap to form between the seal portion and the panel, and making it possible to prevent a decrease in watertight performance.

(2) Also, preferably, the engaging piece and the guide portion are arranged side by side with the main body portion, and the engaging piece has a connecting portion extending radially outward from the main body portion, and an engaging portion extending from the connecting portion toward the seal portion side, being elastically deformable radially inward and engaging with the panel, and the connecting portion has a curved second guide surface on its outer surface, the second guide surface having a curved start point radially inward from the first guide surface and a curved end point radially outward from the first guide surface.
In this case, when attaching the grommet assembly to the panel, the first guide surface is brought into sliding contact with the inner circumferential surface of the through hole, and then the curved second guide surface of the engagement piece is brought into sliding contact with the inner circumferential surface of the through hole, so that the engagement portion of the engagement piece elastically deforms radially inward. Then, the engagement portion of the engagement piece engages with the panel, and the grommet assembly is attached to the panel. This improves the ease of attachment.

(3) Also, in the grommet assembly described in (2), preferably, the protrusion and the engaging piece are arranged side by side on the main body portion, and the protrusion has an opposing surface that faces the inner surface of the through hole and is capable of contacting the inner surface, and a third guide surface that is arranged on the sealing portion side of the second guide surface and inclines radially inward as it moves from the opposing surface toward the first direction.
When attaching the grommet assembly to the panel, the curved second guide surface is brought into sliding contact with the inner surface of the through hole, and the grommet assembly may become temporarily unstable until the engagement portion elastically deforms and engages with the panel.
According to the above-described configuration, the third guide surface can contact the inner circumferential surface of the through hole and function as an auxiliary to stabilize the position of the grommet assembly. Even if the grommet assembly is displaced due to, for example, vibration while attached to the panel, the opposing surface of the protrusion contacts the inner circumferential surface of the through hole, limiting the displacement.

(4) In the grommet assembly according to (3) above, the protrusions are preferably provided on both sides of the engagement piece.
In this case, the third guide surface of the protrusion functions as a guide at two locations on either side of the engagement piece, the grommet assembly is supported at two locations relative to the through hole, and the posture of the grommet assembly can be stabilized when it is installed.
Furthermore, the opposing surfaces located on both sides of the engaging piece stabilize the posture of the grommet assembly when it is attached to the panel, allowing its waterproofing performance to be maintained, and also makes it difficult for the engaging piece to disengage from the panel, contributing to preventing the grommet assembly from falling off.

(5) In the grommet assembly according to (3) or (4) above, preferably, a plurality of the protrusions are provided at intervals along the outer periphery of the main body.
In this case, the protrusion has a configuration in which a plurality of opposing surfaces and a plurality of third guide surfaces are provided at intervals along the outer periphery of the main body. Therefore, when the main body of the inner member is inserted into the through hole to attach the grommet assembly to the panel, the third guide surface aligns the center of the through hole, making it possible to attach the grommet assembly in an accurate position. Furthermore, even if the grommet assembly is displaced in various directions due to, for example, vibration, the displacement is restricted by the opposing surface coming into contact with the inner periphery of the through hole.

(6) In the grommet assembly according to any one of (2) to (5) above, preferably, a plurality of the engagement pieces are provided at intervals along the outer periphery of the main body portion.
In this case, the engaging piece has a configuration in which a plurality of second guide surfaces are provided at intervals along the outer periphery of the main body, so that when the main body of the inner member is inserted into the through hole to attach the grommet assembly to the panel, the second guide surfaces align the main body with the through hole, making it possible to attach the grommet assembly in an accurate position.

(7) Also, preferably, the guide portion has two pillar portions extending in the first direction, and each of the two pillar portions has the first guide surface.
According to the above-mentioned configuration, the post portion comes into contact with the through hole at two points, which makes it possible to stabilize the posture of the grommet assembly, bring the main body portion close to the through hole, and attach the grommet assembly to the panel.

(8) In the grommet assembly described in (7) above, the engagement piece is preferably provided between the two pillar portions.
According to the above-mentioned configuration, when the posture of the grommet assembly is stabilized by the two pillars and the main body is brought close to the through hole, the grommet assembly can be attached to the panel by the engagement piece between the two pillars. In other words, it is possible to attach the grommet assembly while keeping its posture stable.

(9) Also, in the grommet assembly described in (7) or (8), preferably, the pillar portion has a first long piece having the first guide surface, and a second long piece having a surface that intersects with the first guide surface.
According to the above configuration, the rigidity of the post portion is increased, which suppresses deflection of the post portion (guide portion) when the first guide surface is brought into sliding contact with the through hole, thereby making it possible to stabilize the mounting posture of the grommet assembly.

(10) Also, preferably, the grommet has a tubular portion having a hole through which the electric wire passes, the direction in which the electric wire passes through the tubular portion is inclined with respect to a reference line of the first direction, and the guide portion is provided on the side opposite to the direction in which the electric wire is pulled out from the tubular portion toward the second surface side of the panel.
According to this configuration, even when the electric wire is sharply bent, it is difficult for unnecessary external force to be generated in the grommet assembly. Furthermore, even if the guide portion is long, it does not interfere with the electric wire.

(11) Also, preferably, the grommet has a tubular portion having a hole through which the electric wire passes, the direction in which the electric wire passes through the tubular portion is inclined with respect to a reference line of the first direction, the grommet has a fitting portion protruding from the grommet for positioning with the inner member, and the fitting portion is provided in a direction in which the electric wire is pulled out from the tubular portion toward the first surface side of the panel.
According to this configuration, even in the case of a sharply bent electric wire, it is difficult to apply unnecessary external force to the grommet assembly. In addition, the fitting portion determines the position of the grommet and the inner member, and the inner member is attached to the grommet in a specified direction. The fitting portion is provided by protruding from the grommet, and is located in a space (dead space) formed between the electric wire that is inclined with respect to the reference line and the panel, thereby enabling space saving.

(12) A wire harness of this embodiment includes an electric wire passing through a through hole provided in a panel having a first surface and a second surface opposite to the first surface, and a grommet assembly attached to the panel to protect the electric wire, the grommet assembly being any one of the grommet assemblies described in (1) to (11).
According to the wire harness, the grommet assembly can be easily attached, and deterioration of the watertight performance can be suppressed.

<Details of the embodiment of the present disclosure>
Hereinafter, the details of the embodiments of the present disclosure will be described with reference to the drawings. Note that at least some of the embodiments described below may be combined in any combination.

[About wire harnesses]
A wire harness according to an embodiment will be described. The wire harness is used to electrically connect a plurality of electrical devices. FIG. 1 is a perspective view showing a part of a wire harness 7 according to the present embodiment. The wire harness 7 shown in FIG. 1 is for a vehicle such as an electric vehicle or a hybrid vehicle. Examples of the electrical devices include a battery and an inverter mounted on the vehicle. For example, the first electrical device is installed in an engine room on the outside of the vehicle, and the second electrical device is installed in an area on the cabin side (inside of the vehicle). The inside and outside of the vehicle are partitioned by a plate-shaped panel (vehicle body panel) P, and the electric wires 6 of the wire harness 7 are wired through a through hole Q provided to penetrate the panel P.

The wire harness 7 includes electric wires 6 passing through the through hole Q and a grommet assembly 10 for protecting the electric wires 6. The grommet assembly 10 is attached to the portion of the panel P where the through hole Q is formed. Figure 2 is a perspective view of the grommet assembly 10. Figure 3 is an exploded perspective view of the grommet assembly 10. Figure 4 is a cross-sectional view of the grommet assembly 10. In each figure, the panel P and the electric wires 6 are indicated by imaginary lines (two-dot chain lines).

The panel P has a first surface P1 and a second surface P2 opposite the first surface P1. A through hole Q is provided that penetrates from the first surface P1 to the second surface P. In this embodiment, the through hole Q has an oval shape, but the shape is not limited.

The "directions" in the grommet assembly 10 will now be defined.
The direction from the first surface P1 side toward the second surface P2 side of the panel P is defined as the "first direction." The direction opposite to the first direction is defined as the "second direction." If the direction along the center line L of the through hole Q is defined as the "axial direction," then the direction toward one side in the axial direction is the "first direction," and the direction toward the other side in the axial direction is the "second direction."
The direction from the center (center line L) of the through hole Q to the outside is defined as the "radial direction." The direction perpendicular to the axial direction is included in the "radial direction."
The directions of the grommet assembly 10 are based on the above definitions when the grommet assembly 10 is attached to the panel P. In the description of the present disclosure, the state in which the grommet assembly 10 is attached to the panel P is referred to as an "attached state."

The grommet assembly 10 comprises a grommet 11 and an inner member 31. The grommet 11 covers the through hole Q from the first surface P1 side. The grommet 11 has a hole 15 through which the electric wire 6 passes. The inner member 31 is attached to the grommet 11 and is integrated with the grommet 11. The inner member 31 is annular as a whole, and the electric wire 6 passes through its inner periphery. The direction from the center of the annular inner member 31 to the outside coincides with the radial direction. The grommet 11 is mainly responsible for watertightness between the grommet 11 and the panel P. The inner member 31 is mainly responsible for fixing the grommet 11 to the panel P.

The grommet 11 is made of resin and is capable of elastic deformation, for example, ethylene propylene diene rubber (EPDM). The inner member 31 is made of resin and is capable of elastic deformation. The inner member 31 is made of a material harder than the grommet 11, for example, polypropylene (PP).

[Regarding grommet 11]
The grommet 11 has a flat cover portion 12 that covers the through hole Q, a cylindrical peripheral wall portion 13 provided along the outer periphery of the cover portion 12, and a tube portion 14 provided with a hole 15 through which the electric wire 6 passes. The tube portion 14 is connected to the center of the cover portion 12. The direction in which the electric wire 6 passes through the tube portion 14 is inclined with respect to a reference line in the first direction. In Fig. 4, the reference line coincides with the center line L of the through hole Q. The electric wire 6 is in close contact with the tube portion 14.

The peripheral wall portion 13 has an annular seal portion 16 that contacts the first surface P1 of the panel P. The seal portion 16 has a plurality of lips 16a, and the lips 16a contact the first surface P1 around the entire circumference of the through hole Q, thereby achieving water-stopping performance. A circumferential groove 17 is formed between the peripheral wall portion 13 and the outer periphery of the cover portion 12 on the inside of the grommet 11. The circumferential groove 17 is fitted with an annular flange portion 32 of the inner member 31, which will be described later. The peripheral wall portion 13 has a fitting portion 18 that protrudes radially outward at one location in the circumferential direction. As will be described later, the fitting portion 18 functions to position the inner member 31. To this end, the fitting portion 18 has a recess 19 inside that connects to the circumferential groove 17 (see FIG. 4).

1 and 4, the radial component perpendicular to the first direction (the axial direction) in the direction in which the wire 6 is pulled out from the tubular portion 14 of the grommet 11 to the first surface P1 side of the panel P is defined as the "one radial direction." The one radial direction is indicated by an arrow R1 in FIGS. 1 and 4. In contrast, the radial component perpendicular to the first direction (the axial direction) in the direction in which the wire 6 is pulled out from the tubular portion 14 to the second surface P2 side of the panel P is defined as the "other radial direction." The other radial direction is indicated by an arrow R2 in FIG. The one radial direction and the other radial direction are opposite directions.

The fitting portion 18 is provided at one radial position (the position on the side of the arrow R1). In other words, the fitting portion 18 is provided in the direction in which the electric wire 6 is pulled out from the tube portion 14 toward the first surface P1 of the panel P. The fitting portion 18 is provided by protruding from the grommet 11, and is located in the space (dead space) U formed between the electric wire 6, which is inclined with respect to the reference line, and the first surface P1 of the panel P, thereby enabling space saving.

[Regarding the inner member 31]
The inner member 31 (see FIG. 3 ) has an annular flange portion 32, a cylindrical main body portion 33, an engagement piece 34, a guide portion 35, and a protrusion portion 37. The inner member 31 is annular as a whole, and in the attached state, the axial direction of the inner member 31 coincides with the axial direction of the through hole Q.

The flange portion 32 is fitted into the circumferential groove 17 of the grommet 11 and attached. The flange portion 32 (see FIG. 4) is sandwiched in the first direction (axial direction) between the cover portion 12 and a part of the peripheral wall portion 13, and the flange portion 32 and the grommet 11 are in close contact with each other. The flange portion 32 has a protrusion 38 that protrudes radially outward at one location in the circumferential direction. With the flange portion 32 fitted into the circumferential groove 17, the protrusion 38 fits into the recess 19 in the fitting portion 18 of the grommet 11. This positions the grommet 11 and the inner member 31, and the inner member 31 is attached to the grommet 11 in a specified orientation.

The main body 33 is cylindrical, and in the attached state, a portion of the main body 33 is provided on the inner periphery side of the through hole Q. The main body 33 extends in the first direction from the inner periphery of the flange portion 32, and the end of the main body 33 in the first direction is located on the first direction side of the seal portion 16. In other words, the main body 33 protrudes in the first direction further than the seal portion 16. The main body 33 has an outer peripheral contour shape corresponding to the shape of the through hole Q. Since the through hole Q is oval, the main body 33 has an outer peripheral contour shape of an oval. The main body 33 has a pair of short side wall portions 39, 39 located on both sides of the long axis direction of the oval, and long side wall portions 40, 40 located on both sides of the short axis direction.

The guide portion 35 functions as an auxiliary member for the operation of attaching the grommet assembly 10 to the panel P. The operation of attaching the grommet assembly 10 to the panel P is simply referred to as the "attachment operation." The guide portion 35 is provided extending from a part of the main body portion 33 in the first direction. The guide portion 35 has a first guide surface 36 that can slide against the inner peripheral surface of the through hole Q during the attachment operation. The guide portion 35 has two pillar portions 45, 45 that are provided extending in the first direction. Each of the two pillar portions 45, 45 has a first guide surface 36.

Figure 5 is an enlarged perspective view showing a portion of the grommet assembly 10. Each pillar portion 45 has a first long piece 46 having a first guide surface 36, and a second long piece 47. The second long piece 47 has a surface 48 that intersects with the first guide surface 36 (in the illustrated example, the surface 48 is perpendicular). In a cross section viewed from the longitudinal direction of the pillar portion 45, the pillar portion 45 has an L-shape. The two pillar portions 45, 45 are connected by a rib 49 on the side of their base portions 45a, 45a. The rib 49 is a portion that extends from a portion of the main body portion 33 in the first direction.

The guide portion 35 is provided at one radial position (the position on the arrow R1 direction side) in the main body portion 33 (see FIG. 4). In other words, the guide portion 35 is provided on the side opposite to the direction in which the electric wire 6 is pulled out from the tube portion 14 of the grommet 11 to the second surface P2 side of the panel P. Therefore, even if the guide portion 35 is long, it does not interfere with the electric wire 6.

The guide portion 35 is provided at only one location on one of the short side wall portions 39 of the main body portion 33. An engagement piece 34 is provided on the main body portion 33 (one of the short side wall portions 39) next to the one guide portion 35. Specifically, as shown in FIG. 5, one engagement piece 34 is provided between the bases 45a, 45a of the two pillar portions 45, 45. The engagement piece 34 is provided on the outer periphery of the main body portion 33. Multiple engagement pieces 34 (four in the illustrated example) are provided at intervals along the outer periphery of the main body portion 33.

All of the engagement pieces 34 have the same shape. Using FIG. 4 as an example, the engagement pieces 34 sandwich the panel P between themselves and the seal portion 16, thereby fixing the grommet assembly 10 to the panel P. One engagement piece 34 is provided on one short side wall portion 39 of the main body portion 33, and one engagement piece 34 is provided on one long side wall portion 40. Thus, as shown in FIG. 2, the engagement pieces 34 are provided at two locations on both sides in the long axis direction and two locations on both sides in the short axis direction. The shapes of the engagement pieces 34 are all the same, but may differ, for example, in terms of the width dimension perpendicular to the first direction.

In Figures 4 and 5, the engagement piece 34 has a connecting portion 51 having a curved shape that extends radially outward from the main body portion 33, and an engagement portion 52 that extends from the connecting portion 51 toward the seal portion 16 and engages with the panel P. The tip of the engagement piece 34 is freely elastically deformable, and by coming into contact with the panel P during the installation work, the engagement portion 52 can elastically deform radially inward.

The connecting portion 51 has a curved second guide surface 53 on the outer surface of the connecting portion 51. As described above, the engaging piece 34 is provided between the two pillar portions 45, 45 of the guide portion 35, and the guide portion 35 and the engaging piece 34 are arranged side by side in the circumferential direction. The circumferential direction is the direction along the circumferential direction of the main body portion 33, which is cylindrical (annular). As shown in FIG. 4, the second guide surface 53 has a curved shape (cylindrical surface shape) that is convex radially outward, with a bending start point S radially inward from the first guide surface 36 and a bending end point E radially outward from the first guide surface 36.

The engaging portion 52 has an inclined surface 54 on its radially outer side. The inclined surface 54 is provided continuously from the second guide surface 53, and is a surface that inclines in a radially outward direction as it approaches the second direction, which is opposite to the first direction. As will be described later, during the mounting work, the panel P (the inner peripheral surface of the through hole Q) presses the second guide surface 53 and the inclined surface 54, so that the engaging portion 52 elastically deforms toward the outer peripheral surface 33a of the main body portion 33, which is radially inward. The engaging portion 52 further has a first contact surface 55 that contacts the inner peripheral surface of the through hole Q and a second contact surface 56 that contacts the second surface P2 of the panel P in the mounted state.

When the second contact surface 56 contacts the second surface P2 of the panel P and the seal portion 16 contacts the first surface P1 of the panel P, the grommet assembly 10 is attached to the panel P and cannot move axially. When the first contact surface 55 of each of the multiple (four) engagement pieces 34 contacts the inner circumferential surface of the through hole Q, the grommet assembly 10 is attached to the panel P and cannot move radially.

The protrusions 37 are provided on the outer periphery of the main body 33. The protrusions 37 protrude radially outward from the outer periphery 33a of the main body 33. A plurality of protrusions 37 (eight in the illustrated example) are provided at intervals along the outer periphery of the main body 33. The protrusions 37 and the engagement pieces 34 are provided side by side at intervals on the main body 33. The shapes of the protrusions 37 may all be the same or may be different. In the illustrated example, the protrusions are different in width dimension perpendicular to the first direction.

The arrangement of the protrusions 37 and the engagement pieces 34 will now be described. As shown in FIG. 2, two protrusions 37, 37 are provided on both sides of one engagement piece 34. To explain further, in one short side wall portion 39 of the main body portion 33, two protrusions 37, 37 are provided on both sides of one engagement piece 34, and in one long side wall portion 40, two protrusions 37, 37 are provided on both sides of one engagement piece 34. In other words, the pair of protrusions 37, 37 located on both sides of one engagement piece 34 are provided at two locations on both sides in the long axis direction and two locations on both sides in the short axis direction. As a result, a total of eight protrusions 37 are provided on the main body portion 33.

In the attached state, the protrusion 37 can contact the inner circumferential surface of the through hole Q. As shown in FIG. 5, the protrusion 37 has an opposing surface 62 located radially outward from the outer circumferential surface 33a of the main body 33, and a third guide surface 63 continuing from the opposing surface 62 in the first direction. The opposing surface 62 is a flat surface, and in the attached state, it faces the inner circumferential surface of the through hole Q and can contact the inner circumferential surface. More specifically, in the attached state, the opposing surface 62 faces the inner circumferential surface of the through hole Q with or without a gap. When the grommet assembly 10 begins to be displaced in a direction that reduces the gap between the opposing surface 62 and the through hole Q due to an external force such as vibration, the opposing surface 62 contacts the inner circumferential surface of the through hole Q before the outer circumferential surface 33a of the main body 33.

The opposing surface 62 is provided at the same position in the first direction as the first contact surface 55 of the engagement portion 52. The third guide surface 63 is provided closer to the seal portion 16 than the second guide surface 53 of the engagement piece 34. The third guide surface 63 is provided at the same position in the first direction as a part of the inclined surface 54 of the engagement portion 52. The third guide surface 63 is a surface that inclines in a direction radially inward as it moves from the opposing surface 62 toward the first direction. As shown in FIG. 5, in the short side wall portion 39 where the guide portion 35 is provided, a part of the first guide surface 36 and a part of the third guide surface 63 are continuous.

As described above, in the grommet assembly 10, when the cylindrical main body 33 is divided into four regions (short side wall portions 39, 39 and long side wall portions 40, 40) along the circumferential direction, two protrusions 37, 37 and one engagement portion 52 are provided in each region, and a guide portion 35 is provided in only one region (short side wall portion 39).

[Regarding the Grommet Assembly 10 of the Embodiment]
As described above, the grommet assembly 10 of the embodiment includes the grommet 11 and the inner member 31 attached to the grommet 11. The grommet 11 has the annular seal portion 16 that contacts the first surface P1.
The inner member 31 has a cylindrical main body portion 33 provided on the inner periphery of the through hole Q in the attached state, an engagement piece 34 that engages with the panel P, a guide portion 35, and a protrusion portion 37. The guide portion 35 is provided extending from the main body portion 33 in the first direction. The guide portion 35 has a first guide surface 36 that can come into sliding contact with the inner periphery of the through hole Q during the attachment work. The protrusion portion 37 is provided on the outer periphery of the main body portion 33 and protrudes radially outward from the main body portion 33. The protrusion portion 37 can come into contact with the inner periphery of the through hole Q in the attached state.

During the installation process, the grommet assembly 10 having the above-described configuration can be attached by first sliding the first guide surface 36 against the inner peripheral surface of the through hole Q as shown in FIG. 6, and then inserting the main body 33 into the through hole Q as shown in FIGS. 7, 8, and 4. The first guide surface 36 positions the grommet assembly 10 relative to the through hole Q, improving the ease of installation.

In the above-mentioned attached state, even if the grommet assembly 10 is displaced due to, for example, vibration, the protrusion 37 contacts the inner peripheral surface of the through hole Q, limiting the displacement. This prevents the grommet assembly 10 from tilting, making it difficult for a gap to form between the seal portion 16 and the panel P (first surface P1), and making it possible to prevent a decrease in water-stopping performance.

In the attached state (see FIG. 4), the direction in which the electric wire 6 penetrates the tubular portion 14 of the grommet 10 is inclined with respect to the reference line of the first direction (the center line L of the through hole Q). Therefore, even in the case of a sharply bent arrangement of the electric wire 6, it is difficult to generate unnecessary external forces on the grommet assembly 10. As a result, the grommet assembly 10 is difficult to displace, it is possible to suppress a decrease in the water-stopping performance, and the grommet assembly 10 is difficult to fall off.

The guide portion 35 has two pillar portions 45, 45 extending in the first direction. Therefore, during the installation work, the pillar portions 45, 45 come into contact with the through hole Q at two points. As a result, as shown in Figures 6 to 8 and Figure 4, it is possible to stabilize the posture of the grommet assembly 10, bring the main body portion 33 close to the through hole Q, and install the grommet assembly 10 on the panel P.

An engagement piece 34 is provided between the two pillars 45, 45 (see Figure 2). During the installation work, when the posture of the grommet assembly 10 is stabilized by the two pillars 45, 45 and the main body 33 is brought close to the through hole Q, the engagement piece 34 between these two pillars 45, 45 allows the grommet assembly 10 to be attached to the panel P. In other words, the installation work can be performed while keeping the posture of the grommet assembly 10 stable.

Each pillar 45 has a first long piece 46 having a first guide surface 36 and a second long piece 47 having a surface 48 perpendicular to the first guide surface 36 (see FIG. 5). This configuration increases the rigidity of the pillar 45. During the installation work, deflection of the pillar 45 is suppressed, and the installation posture of the grommet assembly 10 is stabilized.

The guide portion 35 and the engagement piece 34 are arranged side by side on the main body portion 33. The engagement piece 34 has a connecting portion 51 extending radially outward from the main body portion 33, and an engagement portion 52 extending from the connecting portion 51 toward the seal portion 16. The connecting portion 51 has a curved second guide surface 53 on the outer surface of the connecting portion 51 (see Figures 6 and 7). The second guide surface 53 has a curved shape with a bending start point S radially inward from the first guide surface 36 and a bending end point E radially outward from the first guide surface 36.

Therefore, during the installation work, as shown in FIG. 6, the first guide surface 36 is brought into sliding contact with the inner circumferential surface of the through hole Q, and then, as shown in FIG. 7, the curved second guide surface 53 is brought into sliding contact with it, and as shown in FIG. 8, the engagement portion 52 of the engagement piece 34 elastically deforms radially inward. Then, as shown in FIG. 4, the engagement portion 52 engages with the panel P, and the grommet assembly 10 is attached to the panel P. The grommet assembly 10 is continuously supported by the first guide surface 36 and the second guide surface 53 against the panel P, improving the ease of installation work.

During the installation work, as shown in Figure 7, the curved second guide surface 53 is brought into sliding contact with the inner surface of the through hole Q, and the first guide surface 36 moves away from the inner surface of the through hole Q until the engagement portion 52 elastically deforms (see Figure 8) and engages with the panel P, which may cause the grommet assembly 10 to become temporarily unstable.
Therefore, in this embodiment (see FIG. 5 ), the engagement piece 34 and the protrusion 37 are provided side by side on the main body portion 33. The protrusion 37 has a third guide surface 63 that is inclined inward in the radial direction from the opposing surface 62 toward the first direction.

During the installation work, the third guide surface 63 can contact the inner circumferential surface of the through hole Q until the first guide surface 36 passes over the inner circumferential surface of the through hole Q and functions as an auxiliary to stabilize the posture of the grommet assembly 10. Furthermore, the protrusion 37 is provided on both sides of the engagement piece 34. Therefore, the third guide surface 63 of the protrusion 37 functions as a guide at two points on both sides of the engagement piece 34. In other words, the grommet assembly 10 is supported at two points with respect to the through hole Q, making it possible to further stabilize its posture.

The protrusion 37 has an opposing surface 62 that can contact the inner circumferential surface of the through hole Q in the attached state. Therefore, even if the grommet assembly 10 is displaced due to vibration, for example, in the attached state (see FIG. 4), the opposing surface 62 contacts the inner circumferential surface of the through hole Q, limiting the displacement. Moreover, the protrusion 37 is provided on both sides of the engagement piece 34. Therefore, in the attached state, the opposing surfaces 62 of the protrusion 37 function at two locations on both sides of the engagement piece 34. The opposing surfaces 62, 62 located on both sides of the engagement piece 34 make the posture of the grommet assembly 10 even more stable, and the water-stopping performance can be maintained. In addition, the engagement of the engagement piece 34 with the panel P is difficult to release, which contributes to preventing the grommet assembly 10 from falling off.

The protrusions 37 are provided in a plurality at intervals along the outer periphery of the main body 33. In particular, the protrusions 37 are provided in four radial directions centered on a reference line in the first direction (the center line L of the through hole Q). In other words, the opposing surfaces 62 and the third guide surfaces 63 of the protrusions 37 are provided in a plurality at intervals along the outer periphery of the main body 33.
Therefore, when inserting the main body portion 33 into the through hole Q for the installation work, the multiple third guide surfaces 63 align the main body portion 33 with the through hole Q, making it possible to install the grommet assembly 10 in an accurate posture.
Furthermore, even if the grommet assembly 10 is displaced in various directions due to vibration, for example, in the attached state, the opposing surface 62 comes into contact with the inner peripheral surface of the through hole Q, thereby restricting the displacement.

The engaging pieces 34 are provided in a plurality of positions spaced apart along the outer periphery of the main body 33. In particular, the engaging pieces 34 are provided in four radial directions centered on a reference line in the first direction (the center line L of the through hole Q). In other words, the second guide surfaces 53 and the inclined surfaces 54 of the engaging pieces 34 are configured to be provided in a plurality of positions spaced apart along the outer periphery of the main body 33.
Therefore, when inserting the main body portion 33 into the through hole Q for the installation work, as shown in Figures 7 and 8, the second guide surface 53 and the inclined surface 54 align the main body portion 33 with the through hole Q, making it possible to install the grommet assembly 10 in an accurate posture.

〔others〕
The seal portion 16 of the grommet 11 may have a shape other than that shown in the drawings. The direction in which the tubular portion 14 of the grommet 11 pays out the electric wire 6 may also be changed.
The number of engagement pieces 34 and protrusions 37 of the inner member 31 can be changed according to the size of the through hole Q, and may be greater than that shown in the figure, for example. The guide portion 35 has two independent pillar portions 45, 45, but these pillar portions 45, 45 may be connected at their tips.

The above-described embodiment is illustrative in all respects and is not restrictive. The scope of the present invention is indicated by the claims, not by the above-described embodiment, and includes all modifications within the scope of equivalents to the configurations described in the claims.

Reference Signs List 6 Electric wire 7 Wire harness 10 Grommet assembly 11 Grommet 12 Cover portion 13 Circumferential wall portion 14 Cylinder portion 15 Hole 16 Sealing portion 16a Lip 17 Circumferential groove 18 Fitting portion 19 Recess 31 Inner member 32 Flange portion 33 Main body portion 33a Outer circumferential surface 34 Engagement piece 35 Guide portion 36 First guide surface 37 Protrusion 38 Convex portion 39 Short side wall portion 40 Long side wall portion 45 Pillar portion 45a Base portion 46 First long piece 47 Second long piece 48 Surface 49 Rib 51 Connecting portion 52 Engagement portion 53 Second guide surface 54 Inclined surface 55 First contact surface 56 Second contact surface 62 Opposing surface 63 Third guide surface L Center line P Panel P1 First surface P2 Second surface Q Through hole U Space

Claims (12)

1. A grommet assembly to be attached to a panel having a first surface and a second surface opposite to the first surface, the panel having a through hole extending from the first surface to the second surface,
a grommet covering the through hole from the first surface side and having a hole through which an electric wire passes;
an annular inner member that is attached to the grommet and through which the electric wire passes on an inner periphery side;
Equipped with
The grommet has an annular seal portion in contact with the first surface,
The inner member is
A cylindrical main body portion provided on an inner peripheral side of the through hole;
an engagement piece provided on an outer periphery of the main body portion and adapted to engage with the panel;
a guide portion extending from the main body portion in a first direction from the first surface side toward the second surface side, the guide portion having a first guide surface capable of slidingly contacting an inner circumferential surface of the through hole;
a protrusion provided on an outer circumferential side of the main body portion and protruding radially outward from the main body portion and capable of contacting an inner circumferential surface of the through hole;
The grommet assembly has The engagement piece and the guide portion are provided side by side on the main body portion,
The engaging piece has a connecting portion extending radially outward from the main body portion, and an engaging portion extending from the connecting portion toward the seal portion, elastically deformable radially inward, and engaging with the panel,
The grommet assembly according to claim 1, wherein the connecting portion has, on an outer surface of the connecting portion, a curved second guide surface having a bend start point radially inward from the first guide surface and a bend end point radially outward from the first guide surface. The protrusion and the engagement piece are provided side by side on the main body,
The protrusion is
an opposing surface that faces an inner circumferential surface of the through hole and is capable of contacting the inner circumferential surface;
The grommet assembly according to claim 2 , further comprising: a third guide surface that is provided closer to the seal portion than the second guide surface and that inclines radially inward as it moves from the opposing surface toward the first direction. The grommet assembly according to claim 3, wherein the protrusions are provided on both sides of the engagement piece. The grommet assembly according to claim 3 or claim 4, wherein the protrusions are provided at intervals along the outer periphery of the main body. The grommet assembly according to any one of claims 2 to 5, wherein the engagement pieces are provided at intervals along the outer periphery of the main body. The grommet assembly according to any one of claims 1 to 6, wherein the guide portion has two pillar portions extending in the first direction, and each of the two pillar portions has the first guide surface. The grommet assembly according to claim 7, wherein the engagement piece is provided between the two pillars. The grommet assembly according to claim 7 or 8, wherein the column portion has a first long piece having the first guide surface and a second long piece having a surface that intersects with the first guide surface. The grommet has a tubular portion provided with the hole through which the electric wire passes,
A direction in which the electric wire passes through the cylindrical portion is inclined with respect to a reference line in the first direction,
The grommet assembly according to claim 1 , wherein the guide portion is provided on a side opposite to a direction in which the electric wire is pulled out from the tubular portion toward the second surface side of the panel. The grommet has a tubular portion provided with the hole through which the electric wire passes,
A direction in which the electric wire passes through the cylindrical portion is inclined with respect to a reference line in the first direction,
The grommet has a fitting portion for positioning the grommet with the inner member, the fitting portion being raised from the grommet,
The grommet assembly according to claim 1 , wherein the fitting portion is provided in a direction in which the electric wire is pulled out from the tubular portion to the first surface side of the panel. A wire harness comprising: an electric wire passing through a through hole provided in a panel having a first surface and a second surface opposite to the first surface; and a grommet assembly attached to the panel to protect the electric wire,
The grommet assembly according to claim 1 , wherein the grommet assembly is a grommet assembly according to any one of claims 1 to 11 .

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