Grommets and wire harnesses

Abstract

To provide a grommet and a wiring harness capable of reducing tensile force of a cylindrical part required when inserting an engaging part into an open hole of an installation object.SOLUTION: A grommet 10 includes: a body part 12 which has a plate like part 121 sealing at least a portion of an open hole 31 provided in a panel 30, and which engages with the open hole; and a bellows part 14 which protrudes from a position displaced from a center location O of the plate like part 121. The body part 12 has: a reinforcement rib 16 extending from the bellows part 14 in the plate like part 121 along a first direction (right direction) through the center location O to an outer edge 122 of the plate like part 121; and a thin wall part 18 provided across the reinforcement rib 16 in a second direction (cross direction) intersecting the first direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to grommets and wire harnesses.

Background Art

[0002] When wiring electric wires in a vehicle or the like for the purpose of waterproofing or the like, a grommet made of an elastic body such as rubber is used. The grommet has a fitting portion that fits into a through hole provided in a vehicle body panel or the like, and a cylindrical portion that is integrally connected to the fitting portion and through which an electric wire is inserted. For example, there is one used for an electric wire routed between the vehicle body and the door of a vehicle. When attaching this grommet to a hole in the panel, with the fitting portion arranged on the back side of the panel and the cylindrical portion inserted into the hole in the panel, the operator can fit the fitting portion into the hole in the panel by pulling the cylindrical portion toward the front side.

[0003] However, in a grommet in which the cylindrical portion is provided at a position shifted to one side rather than the center of the fitting portion, when the operator pulls the cylindrical portion, the force transmitted from the outer peripheral surface of the cylindrical portion to the outer surface of the fitting portion becomes non-uniform, so the workability of fitting is not good. Also, when the set position of the cylindrical portion in the fitting portion is shifted to one side, the insertion force required to fit the portion of the outer edge of the fitting portion that is far from the cylindrical portion into the hole is higher than the insertion force when the cylindrical portion is provided at the center of the fitting portion.

[0004] Therefore, in Patent Document 1, in a grommet in which the set position of the cylindrical portion in the fitting portion is shifted to one side, an outer rib is provided on the outer surface of the fitting portion from the outer peripheral surface of the cylindrical portion, and an inner rib that extends along the same direction as the outer rib on the inner surface of the fitting portion and is connected to the outer edge of the fitting portion is provided. In this way, in Patent Document 1, by providing an outer rib and an inner rib on the grommet, the tensile force from the cylindrical portion is made more likely to be transmitted to the outer edge of the fitting portion, aiming to improve the attachment workability.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] In the grommet described in Patent Document 1, the unevenness of the tensile force transmitted to the outer edge of the fitting portion can be improved by the outer ribs and inner ribs. However, because the grommet described in Patent Document 1 has ribs that make it difficult for the fitting portion to bend and deform, a high tensile force is required when fitting it into the through hole provided in the object to be attached. Therefore, the grommet described in Patent Document 1 still had room for improvement in reducing the tensile force.

[0007] The present invention has been made in view of the above circumstances, and its purpose is to provide a grommet and a wire harness that can reduce the tensile force of the cylindrical portion required when inserting the fitting portion into the through hole of the object to be attached. [Means for solving the problem]

[0008] To achieve the aforementioned objectives, the grommet according to the present invention is characterized by the following: It has a plate-like portion that covers at least a part of the through hole provided in the object to be mounted, and a main body portion that fits into the through hole, The plate-like portion comprises a cylindrical portion that protrudes from a position offset from the center of the plate-like portion, The main body is, In the plate-like portion, there is a thickened portion extending along a first direction from the cylindrical portion, passing through the central position and toward the outer edge of the plate-like portion, The thick portion is provided with a thin portion that crosses it in a second direction intersecting the first direction, to have death , The main body has a first thickened portion and a second thickened portion, which are spaced apart in the first direction and arranged along the first direction. The thin-walled portion is provided such that, at a position between the first thick-walled portion and the second thick-walled portion in the first direction, it extends from a position on one side of the second direction to a position on the other side of the first thick-walled portion and the second thick-walled portion. Grommet.

[0009] Furthermore, in order to achieve the aforementioned objectives, the wire harness according to the present invention has the following features. A wire harness equipped with the above-mentioned grommet. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a grommet that can reduce the tensile force of the cylindrical portion required when inserting the fitting portion into the through hole of the object to be attached.

[0011] The present invention has been briefly described above. Furthermore, the details of the present invention will be further clarified by referring to the attached drawings and reading through the embodiments for carrying out the invention described below (hereinafter referred to as "embodiments"). [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a perspective view of a wire harness equipped with a grommet according to one embodiment of the present invention. [Figure 2] Figure 2 is a perspective view of the grommet shown in Figure 1, viewed from below. [Figure 3] Figure 3 is a cross-sectional view taken along line III-III in Figure 1, showing the state before the main body is fitted into the through-hole in the panel. [Figure 4] Figure 4 shows the state after the main body has been fitted into the through-hole of the panel, as shown in the cross-sectional view of Figure 3. [Modes for carrying out the invention]

[0013] Specific embodiments of the present invention will be described below with reference to the figures. For the sake of explanation, the terms "front," "rear," "up," "down," "left," "right," "front-back direction," "left-right direction," and "up-down direction" will be defined below, as shown in Figures 1 to 4. The "front-back direction," "left-right direction," and "up-down direction" are orthogonal to each other.

[0014] FIG. 1 is a perspective view of a wire harness WH including a grommet 10 according to an embodiment of the present invention. FIG. 1 also shows a panel 30 which is an example of an attachment target. FIG. 2 is a perspective view of the grommet 10 shown in FIG. 1 viewed from below. FIG. 3 is a sectional view taken along line III-III of FIG. 1, showing the state before the main body portion 12 is fitted into the through hole 31 of the panel 30. FIG. 4 is a view showing the state after the main body portion 12 is fitted into the through hole 31 of the panel 30 in the sectional view shown in FIG. 3. In FIG. 1, the harness main body 5 inserted through the grommet 10 is shown by a two-dot chain line, but the illustration of the harness main body 5 is omitted in FIGS. 2 to 4.

[0015] <Grommet 10, Wire harness WH> The grommet 10 is a member (molded product) made of rubber or elastomer, and as shown in FIG. 1, it is attached to a predetermined position of the harness main body 5 to form the wire harness WH. The harness main body 5 is, for example, a collection of a plurality of electric wires wrapped by exterior parts such as a corrugated tube or a resin tape, and connection parts such as connectors are attached to the ends. The wire harness WH is, for example, disposed between a vehicle body panel and a movable member such as a door connected to the vehicle body via a hinge portion or the like. The grommet 10 is attached to the through hole 31 of the panel 30 to prevent liquid such as water from entering between the panel 30 and the harness main body 5 and protect the harness main body 5.

[0016] The grommet 10 integrally has a main body portion 12 that fits into the through hole 31 and a bellows portion 14 which is an example of a cylindrical portion, and is formed such that the harness main body 5 can be inserted therein.

[0017] <Bellows portion 14> The bellows 14 has a cylindrical shape through which a plurality of electric wires can be inserted. One end of the bellows 14 is connected to the main body 12, and the other end is connected to a fitting member (not shown). The bellows 14 has a shape in which large-diameter portions and small-diameter portions are alternately connected in its longitudinal direction, that is, a shape in which the longitudinal section has unevenness, and bending deformation is easily formed. As will be described later, the bellows 14 protrudes upward from a position shifted with respect to the central position O of the plate-like portion 121.

[0018] <main body 12> The main body 12 has a plate-like portion 121, an annular wall portion 125 which is an example of a wall portion, a locking recess 123, and a lip portion 124, and is configured to be fitted into a through hole 31 provided in the panel 30.

[0019] The plate-like portion 121 is a flat plate-like member that closes at least a part of the through hole 31 provided in the panel 30 in a plan view (hereinafter simply referred to as a plan view) when viewed in the vertical direction. The outer edge 122 of the plate-like portion 121 has an oval shape in which two semi-circular arcs are connected by a pair of line segments in a plan view. The outer edge 122 of the plate-like portion 121 has a shape corresponding to the through hole 31 of the panel 30 and is sized smaller than the through hole 31.

[0020] The bellows 14 is provided on the plate-like portion 121 so as to protrude upward from a position shifted with respect to the central position O. That is, the bellows 14 is connected to the plate-like portion 121 such that its center is arranged at a position shifted from the central position O of the plate-like portion 121. The central position O is the intersection of a virtual straight line extending in the left-right direction and a virtual straight line extending in the front-back direction, which are shown by a one-dot chain line in FIG. 1. The virtual straight line extending in the left-right direction passes through the center of the width of the plate-like portion 121 in the front-back direction, and the virtual straight line extending in the front-back direction passes through the center of the width of the plate-like portion 121 in the left-right direction.

[0021] The annular wall portion 125 has its upper edge connected to the outer edge 122 of the plate-like portion 121, and its lower edge connected to the lip portion 124 via a locking recess 123. The locking recess 123 and the lip portion 124 are provided around the entire circumference of the annular wall portion 125. The annular wall portion 125 has a first portion 125a near the lower edge. The first portion 125a is the part that protrudes to the outside of the through hole 31 when the main body portion 12 is fitted into the through hole 31 of the panel 30 (see Figure 4). In the state shown in Figure 4, when the main body portion 12 is fitted into the through hole 31 of the panel 30 (see Figure 4), the bottom surface of the locking recess 123 contacts the inner circumferential surface of the through hole 31, and the lip portion 124 contacts the surface of the panel 30, maintaining a watertight seal between the panel 30 and the locking recess 123.

[0022] The main body portion 12 has a reinforcing rib 16, which is an example of a thick-walled portion, and a thin-walled portion 18.

[0023] <Reinforcement rib 16, thin-walled section 18> The reinforcing rib 16 extends along the rightward direction, which is an example of a first direction, from the bellows section 14 on the lower surface of the plate-like portion 121, passing through the central position O shown in Figure 1, toward the outer edge 122 of the plate-like portion 121. By providing such a reinforcing rib 16 on the plate-like portion 121, the thickness of the plate-like portion 121 can be reduced while ensuring the strength of the main body portion 12. As shown in Figure 3, the reinforcing rib 16 has a roughly rectangular parallelepiped shape, with a thickness d2 greater than the thickness d1 of the plate-like portion 121, i.e., its vertical size. The reinforcing rib 16 extends from the periphery of the bellows section 14 on the plate-like portion 121 toward the outer edge 122 of the plate-like portion 121. The right end of the reinforcing rib 16 connects to the inner circumferential surface of the annular wall portion 125 below the outer edge 122 (see Figures 3 and 4). The reinforcing rib 16 is formed such that the thickness d2 decreases as it approaches the annular wall portion 125 near the right end.

[0024] The thin-walled portion 18 is provided on the lower surface of the plate-like portion 121 so as to traverse the reinforcing rib 16 in the front-rear direction. The front-rear direction is an example of a second direction intersecting the first direction. By providing the thin-walled portion 18 so as to traverse the reinforcing rib 16, when the bellows portion 14 is pulled in the direction indicated by arrow A1 in Figure 3 and the main body portion 12 is inserted into the through hole 31, the outer shape of the main body portion 12, specifically the first portion 125a of the annular wall portion 125, becomes more flexible in the direction of arrow A2. The thin-walled portion 18 is the bottom of a groove that is recessed in the direction of the protrusion (upward direction) of the bellows portion 14, where the reinforcing rib 16 is provided on the plate-like portion 121. As shown in Figure 3, the thickness d3 of the thin-walled portion 18 is thinner than the thickness d1 of the plate-like portion 121. The thin-walled portion 18 is provided extending from the lower surface of the plate-like portion 121 to the inner circumferential surface of the annular wall portion 125, and the front and rear ends of the thin-walled portion 18 are located at the first portion 125a, respectively. With this configuration, the main body portion 12 can bend more easily at the thin-walled portion 18, as the plate-like portion 121 and the annular wall portion 125 are more flexible.

[0025] Furthermore, since the reinforcing rib 16 is formed such that its thickness d2 decreases as it approaches the annular wall portion 125, the first portion 125a becomes more easily deformed in the direction of arrow A2.

[0026] <Attaching grommet 10 to panel 30> When attaching the grommet 10 with the above configuration to the panel 30, the worker positions the grommet 10, through which the harness body 5 is inserted, so that the main body portion 12 is located below the panel 30 and the bellows portion 14 protrudes above the panel 30 through the through hole 31 (see Figures 1 and 3). When the worker grasps the bellows portion 14 and pulls it upward (see arrow A1 in Figure 3), the annular wall portion 125 of the main body portion 12 comes into contact with the inner edge of the through hole 31, and the main body portion 12 is inserted into the through hole 31 while elastically deforming in a direction that reduces in diameter along the left-right direction. At this time, because the plate-like portion 121 of the main body portion 12 bends at the thin-walled portion 18, the part of the first portion 125a furthest from the mounting position of the bellows portion 14 is prone to deformation in the direction of arrow A2.

[0027] When the operator pulls the bellows section 14 further upward from a state in which the main body 12 is bent inward along the left-right direction, the first section 125a moves over the inner edge of the through hole 31 and is positioned above the panel 30 by elastic restoration. As a result, as shown in Figure 4, the bottom surface of the locking recess 123 of the main body 12 contacts the inner edge of the through hole 31 and fits into the through hole 31.

[0028] <Effects of Grommet 10 and Wire Harness WH> As explained above, although the bellows section 14 of the grommet 10 is located off-center from the center position O of the plate-shaped section 121, a reinforcing rib 16 is provided inside the main body 12, and a thin-walled section 18 is provided to cross the reinforcing rib 16, making it easier for the plate-shaped section 121 to flex at the thin-walled section 18. Therefore, compared to a grommet 1 without a thin-walled section 18 inside, the grommet 1 can be easily bent in the main body 12 and fitted into the through-hole 31 of the panel 30 even with a small pulling force on the bellows section 14, improving fitting workability. Consequently, when routing a wire harness WH equipped with a grommet 10 to a vehicle or the like, the insertion force of the grommet 10 can be reduced, improving fitting workability.

[0029] Furthermore, the present invention is not limited to the embodiments described above, and can be modified, improved, etc., as appropriate. In addition, the material, shape, dimensions, numerical values, form, number, arrangement, etc. of each component in the embodiments described above are arbitrary and not limited as long as they can achieve the present invention. For example, in the above embodiment, the plate-like portion 121 was flat, but the plate-like portion is not limited to a flat surface and may have a curved surface.

[0030] Furthermore, in the above embodiment, the outer edge 122 of the plate-like portion 121 had an oval shape in plan view, but the outer edge shape of the plate-like portion is not limited to an oval shape and may be any shape such as a circle. Moreover, the cylindrical portion does not have to be bellows-shaped as long as it is hollow, and may be cylindrical or rectangular. In this case, the present invention is useful when the center of gravity of the outer edge of the plate-like portion in plan view is taken as the center position of the plate-like portion, and the cylindrical portion is positioned offset from this center position.

[0031] Herein, the features of the grommet and wire harness according to the embodiments of the present invention described above are briefly summarized and listed below in [1] to [6].

[0032] [1] A plate-shaped portion (121) that covers at least a part of a through hole (31) provided in the mounting object (panel 30), and a main body portion (12) that fits into the through hole, The plate-shaped portion (121) comprises a cylindrical portion (bellows portion 14) that protrudes from a position offset from the central position (O), The main body (12) is, In the plate-like portion, there is a thickened portion (reinforcement rib 16) that extends along a first direction (rightward direction) from the cylindrical portion (bellows portion 14) through the central position (O) toward the outer edge (122) of the plate-like portion, The thickened portion (reinforcement rib 16) is provided with a thinned portion (18) that is positioned to traverse a second direction (front-rear direction) intersecting the first direction, Grommets (10).

[0033] According to the grommet configuration described in [1] above, by providing a thin section in the main body so as to traverse the thick section, the plate-like section is reinforced by the thick section, and the plate-like section flexes at the thin section, so that even with a small pulling force on the cylindrical section, the main body can be inserted into the through hole and fitted.

[0034] [2] The thickened portion (reinforcement rib 16) extends from the peripheral portion of the cylindrical portion in the plate-like portion to the outer edge (122) of the plate-like portion. The grommet described in [1] above.

[0035] With the grommet configuration described in [2] above, the thickened portion can reinforce the plate-like portion from the periphery of the cylindrical portion to its outer edge.

[0036] [3] The thickness (d3) of the thin-walled portion (18) is thinner than the thickness (d1) of the plate-like portion (121). The grommet described in [1] above.

[0037] According to the grommet configuration described in (3) above, the thin-walled portion is made thinner than the plate-like portion, allowing the thin-walled portion to bend easily, thus enabling the grommet's outer shape to be easily elastically deformed.

[0038] [4] The main body portion (12) has a wall portion (annular wall portion 125) connected to the outer edge (122) of the plate-shaped portion (121), The thin-walled portion (18) is provided extending from the plate-like portion to the wall portion. The grommet described in [1] above.

[0039] With the grommet configuration described in [4] above, the thin-walled portion extends from the plate-like portion to the wall portion, allowing the plate-like portion and the wall portion to bend, and thus the outer shape of the grommet can be easily elastically deformed.

[0040] [5] The thin-walled portion (18) is the bottom of a groove formed by recessing the thick-walled portion and the portion of the plate-like portion where the thick-walled portion is provided in the protruding direction (upward) of the cylindrical portion. The grommet described in [1] above.

[0041] According to the grommet configuration described in [5] above, the plate-like portion can be bent along the groove.

[0042] [6] A wire harness (WH) equipped with a grommet (10) as described in any one of [1] to [5] above.

[0043] In the wire harness configuration described in [6] above, a thin section is provided in the main body of the grommet so as to traverse the thick section. With this configuration, the plate-like section is reinforced by the thick section, while the plate-like section flexes at the thin section, so that the main body can be inserted into the through hole and fitted even with a small pulling force on the cylindrical section. [Explanation of Symbols]

[0044] 5. Harness body 10 grommets 12 Main body 14 Bellows 16. Reinforcement ribs (thick sections) 18 Thin-walled section 30 panels 31 Through hole 121 Plate-like part 122 Outer edge 123 Locking recess 124 Lip section 125 Annular wall section 125a Part 1 A1, A2 arrows O center position WH Wire Harness

Claims

1. It has a plate-like portion that covers at least a part of the through hole provided in the object to be mounted, and a main body portion that fits into the through hole, The plate-like portion comprises a cylindrical portion that protrudes from a position offset from the center of the plate-like portion, The main body is, In the plate-like portion, there is a thickened portion that extends along a first direction from the cylindrical portion, passing through the central position and toward the outer edge of the plate-like portion, The thick portion is provided with a thin portion that crosses it in a second direction intersecting the first direction, It has, The main body has a first thickened portion and a second thickened portion, which are spaced apart in the first direction and arranged along the first direction. The thin-walled portion is provided such that, at a position between the first thick-walled portion and the second thick-walled portion in the first direction, it extends from a position on one side of the second direction to a position on the other side of the first thick-walled portion and the second thick-walled portion. Grommet.

2. The thickened portion extends from the peripheral portion of the cylindrical portion in the plate-like portion to the outer edge of the plate-like portion. The grommet according to claim 1.

3. The thin-walled portion is the thick-walled portion and the portion of the plate-like part where the thick-walled portion is provided. The bottom of the groove recessed in the direction of the protrusion of the cylindrical portion, The grommet according to claim 1.

4. The thickness of the thin-walled portion is thinner than the thickness of the plate-like portion. The grommet according to claim 1.

5. The main body portion has a wall portion that connects to the outer edge of the plate-shaped portion, The thickened portion is connected to the inner circumferential surface of the wall portion and is provided such that its thickness decreases as it approaches the wall portion in the vicinity of the wall portion. The thin-walled portion is provided extending from the plate-like portion to the wall portion. The grommet according to claim 1.

6. A wire harness comprising a grommet according to any one of claims 1 to 5.

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