Grommet, wire harness with grommet, and wire harness mounting structure
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- AUTONETWORKS TECH LTD
- Filing Date
- 2026-01-09
- Publication Date
- 2026-08-06
Smart Images
Figure JP2026000495_06082026_PF_FP_ABST
Abstract
Description
Grommet, Wire Harness with Grommet, and Mounting Structure of Wire Harness
[0001] The present disclosure relates to a grommet, a wire harness with a grommet, and a mounting structure of the wire harness.
[0002] Patent Document 1 discloses an automotive grommet including a pair of mounting portions and a bellows-shaped hollow cylindrical portion integrally connecting between the pair of mounting portions via elbow-shaped portions, and having a spiral portion with continuous ridges and valleys formed in the bellows-shaped hollow cylindrical portion. Such a grommet is attached between a door and a vehicle body. The bellows-shaped hollow cylindrical portion is for improving the followability against the torsional action applied to the grommet when the door is opened and closed, and also for improving durability and waterproofness.
[0003] Japanese Patent Application Laid-Open No. 2007-157495
[0004] It is desired that the insertion of the wire harness into the grommet is easy. Also, it is desired that buckling of the grommet is suppressed.
[0005] Therefore, an object is to provide a technique that can facilitate the insertion of the wire harness into the grommet and suppress buckling of the grommet.
[0006] The grommet of the present disclosure includes a cylindrical portion through which a wire harness is passed, and the cylindrical portion includes a first cylindrical portion formed with an engaging portion on an outer surface that engages with a peripheral edge of a hole in a vehicle body panel, and a second cylindrical portion communicating with the first cylindrical portion. The second cylindrical portion includes a helical bellows cylindrical portion in which a first ridge portion and a first valley portion extend in a spiral shape around the axis of the cylindrical portion. At least one of the first ridge portion or the first valley portion has a second ridge portion provided in a part along the extending direction in which it extends in a spiral shape, and a second valley portion provided in another part along the extending direction.
[0007] According to the present disclosure, it is possible to provide a technique that can facilitate the insertion of the wire harness into the grommet and suppress buckling of the grommet.
[0008] Figure 1 is a perspective view showing a grommet according to Embodiment 1. Figure 2 is a front view showing the grommet. Figure 3 is a rear view showing the grommet. Figure 4 is a top view showing the grommet. Figure 5 is a cross-sectional perspective view taken obliquely from a cross section along the line V-V in Figure 2. Figure 6 is a side view showing the grommet in use. Figure 7 is a side view showing the grommet in use.
[0009] [Description of Embodiments of the Disclosure] First, embodiments of the Disclosure will be listed and described.
[0010] The grommet, wire harness with grommet, and mounting structure for the wire harness described herein are as follows.
[0011] (1) A grommet comprising a cylindrical portion through which a wire harness is passed, the cylindrical portion comprising a first cylindrical portion having an engaging portion formed on its outer surface that engages with the peripheral edge of a hole in a vehicle body panel, and a second cylindrical portion communicating with the first cylindrical portion, the second cylindrical portion comprising a helical bellows cylindrical portion having a first peak and a first valley that extend helically around the axis of the cylindrical portion, and at least one of the first peak or the first valley having a second peak provided in a part along the extending direction that extends helically, and a second valley provided in the other part along the extending direction.
[0012] According to the grommet of (1), the helical bellows section can be deformed, including a change in its inner diameter, by being twisted along the circumferential direction. In this case, the helical bellows section can be deformed to expand or contract in diameter depending on the direction of twisting. For example, if the wiring member or the connector at the end of the wiring member in a wire harness is the same diameter as or thicker than the section, expanding the diameter of the helical bellows section makes it easier to pass the wire harness through the section. Also, for example, if the wiring member is thinner than the section, after passing the wiring member through the section, contracting the diameter of the helical bellows section makes it possible to make the helical bellows section fit tightly against the outer circumference of the wiring member. Furthermore, since the inner diameter of the first section is larger than the inner diameter of the helical bellows section, it is also easy to pass the wire harness through the first section. As a result, it becomes easier to insert the wire harness into the grommet. In addition, buckling can be suppressed by the expansion and contraction of the second peaks and second valleys. For example, in the case of a grommet connecting the interior of a vehicle to the door, a sharp bend is created to accommodate the opening and closing of the door. Even in such sharp bends, the stretching and contracting of the second peak and second valley suppresses buckling of the grommet.
[0013] (2) The grommet of (1), wherein each of the first peak and the first valley may have the second peak and the second valley. With this grommet, buckling when bending the helical bellows tube can be further suppressed by having each of the first peak and the first valley have the second peak and the second valley.
[0014] (3) A grommet according to (1) or (2), wherein each of the first peaks and first valleys may have a plurality of alternately arranged second peaks and second valleys. With this grommet, each of the first peaks and first valleys has a plurality of alternately arranged second peaks and second valleys, so that buckling can be suppressed when bending the helical bellows tube at multiple locations.
[0015] (4) Any one of the grommets from (1) to (3), wherein the second peaks adjacent to each other in the circumferential direction of the cylindrical portion may be provided in the same region along the axial direction of the second cylindrical portion. With this grommet, bending along the axial direction of the cylindrical portion is absorbed by the multiple second peaks provided in the same region. Therefore, buckling when bending the helical bellows cylindrical portion can be further suppressed.
[0016] (5) Any one of the grommets from (1) to (4), wherein the second valleys adjacent to each other in the circumferential direction of the cylindrical portion may be provided in the same region along the axial direction of the second cylindrical portion. With this grommet, bending along the axial direction of the cylindrical portion is absorbed by the multiple second valleys provided in the same region. Therefore, buckling when bending the helical bellows cylindrical portion can be further suppressed.
[0017] (6) The grommeted wire harness of the present disclosure is a grommeted wire harness comprising one grommet from (1) to (5) and a wire harness passed through the grommet.
[0018] (7) The wire harness mounting structure of the present disclosure further comprises the wire harness with grommet of (6) and a vehicle body panel having the hole formed therein, wherein the peripheral edge of the hole and the engaging portion of the grommet engage with each other.
[0019] [Details of Embodiments of the Disclosure] Specific examples of grommets, wire harnesses with grommets, and mounting structures for wire harnesses of the Disclosure will be described below with reference to the drawings. However, the Disclosure is not limited to these examples and is intended to include all modifications within the meaning and scope of the claims as indicated by the claims.
[0020] In each drawing, some parts of the configuration may be exaggerated or simplified for ease of explanation. Also, the dimensional ratios of each part may differ in each drawing. Furthermore, in this specification, "parallel" and "orthogonal" do not only refer to strictly parallel or orthogonal connections, but also to connections that are approximately parallel or orthogonal within the range that achieves the function and effect of this embodiment.
[0021] [Embodiment 1] The following describes a grommet 10, a wire harness 80 with a grommet, and a mounting structure 110 for the wire harness according to Embodiment 1. Figure 1 is a perspective view showing the grommet 10 according to Embodiment 1. Figure 2 is a front view showing the grommet 10. Figure 3 is a rear view showing the grommet 10. Figure 4 is a plan view showing the grommet 10. Figure 5 is a cross-sectional perspective view taken obliquely from a cross section along the line V-V in Figure 2. Figures 6 and 7 are side views showing the grommet 10 in use. In Figure 6, the vehicle body panel 90 and the door panel 100 are shown by dashed lines. Note that the orientation of the door panel 100 relative to the vehicle body panel 90 changes when the door is opened and closed, but the change in the orientation of the door panel 100 relative to the vehicle body panel 90 is omitted in Figures 6 and 7.
[0022] The grommet 10 includes a cylindrical portion 12 through which the wire harness 82 passes. In this embodiment, the grommet 10 includes a wiring fixing portion 60. The wiring fixing portion 60 may be omitted. The grommet 10 is formed from an elastic material such as rubber or elastomer. The grommet 10 is a molded product, for example, made using a mold or a silicone mold.
[0023] The cylindrical portion 12 includes a first cylindrical portion 14, a second cylindrical portion 20, and a third cylindrical portion 18 that communicate with each other. The first cylindrical portion 14 and the third cylindrical portion 18 are parts of the cylindrical portion 12 that are aligned along the axial direction, and the other part is the second cylindrical portion 20. The first cylindrical portion 14 and the third cylindrical portion 18 are parts that are attached to the vehicle body. The first cylindrical portion 14 engages with the peripheral edge of the hole 91 in the vehicle body panel 90. Specifically, a fitting groove 16 is formed on the outer surface of the first cylindrical portion 14. The peripheral edge of the hole 91 in the vehicle body panel 90 fits into the fitting groove 16. The third cylindrical portion 18 engages with the peripheral edge of the hole 101 in the door panel 100. Specifically, a fitting groove 19 is formed on the outer surface of the third cylindrical portion 18. The peripheral edge of the hole 101 in the door panel 100 fits into the fitting groove 19. The first cylindrical portion 14 may engage with the peripheral edge of the hole 101 in the door panel 100, or the third cylindrical portion 18 may engage with the peripheral edge of the hole 91 in the vehicle body panel 90. Furthermore, other engagement structures for the fitting groove 19 may be used between the first cylindrical portion 14 and the peripheral edge of the hole 91 in the vehicle body panel 90. Similarly, other engagement structures for the fitting groove 19 may be used between the third cylindrical portion 18 and the peripheral edge of the hole 101 in the door panel 100.
[0024] The first cylindrical portion 14 protects the portion of the wire harness 82 that penetrates the hole 91 in the vehicle body panel 90 from the periphery of the hole 91. The second cylindrical portion 20 protects the portion of the wire harness 82 that extends out of the hole 91 in the vehicle body panel 90. The third cylindrical portion 18 protects the portion of the wire harness 82 that penetrates the hole 101 in the door panel 100 from the periphery of the hole 101. Furthermore, the second cylindrical portion 20 protects the portion of the wire harness 82 that extends out of the hole 101 in the door panel 100. In this embodiment, only one first cylindrical portion 14 and one third cylindrical portion 18 are provided. The first cylindrical portion 14 forms one end of the cylindrical portion 12, and the third cylindrical portion 18 forms the other end of the cylindrical portion 12. In this embodiment, the axial direction of the cylindrical portion 12 follows a single straight line from one end to the other. The cylindrical portion 12 is formed in a straight line when unloaded.
[0025] The second cylindrical portion 20 includes a helical bellows cylindrical portion 22, a first connecting cylindrical portion 34, and a second connecting cylindrical portion 36. The helical bellows cylindrical portion 22 is a cylindrical portion 12 in which a bellows section having a first peak portion 24 and a first valley portion 26 extends helically around the axis of the cylindrical portion 12. In this disclosure, the convex portion on the outer circumferential surface is referred to as the first peak portion 24, and the concave portion on the outer circumferential surface is referred to as the first valley portion 26. On the inner circumferential surface, the concave-convex relationship between the first peak portion 24 and the first valley portion 26 is reversed compared to the outer circumferential surface. That is, on the inner circumferential surface, the first peak portion 24 is concave and the first valley portion 26 is convex.
[0026] Furthermore, the first peak 24 has a second peak 25 provided along the spirally extending direction A, and a second valley 27 provided in another part along the extending direction A. The second peak 25 of the first peak 24 is a portion that is convex on the outer circumference side of the first peak 24. The second valley 27 of the first peak 24 is a portion that is concave on the outer circumference side of the first peak 24. The first valley 26 also has a second peak 25 provided along the extending direction A, and a second valley 27 provided in another part along the extending direction A. The second peak 25 of the first valley 26 is a portion that is convex on the outer circumference side of the first valley 26. The second valley 27 of the first valley 26 is a portion that is concave on the first valley 26. In this embodiment, each of the multiple first peaks 24 and first valleys 26 has a second peak 25 and a second valley 27 (see Figures 1 and 4). However, a structure in which some of the first peaks 24 or some of the first valleys 26 have a second peak 25 and a second valley 27 is also possible.
[0027] The first connecting cylindrical section 34 connects the first cylindrical section 14 to the spiral bellows cylindrical section 22. The second connecting cylindrical section 36 connects the third cylindrical section 18 to the spiral bellows cylindrical section 22. The first connecting cylindrical section 34 and the second connecting cylindrical section 36 are not provided with spiral bellows sections.
[0028] The spiral bellows section 22 has a first end section 30 located at the end on the first section 14 side, a second end section 40 located at the end on the third section 18 side, and a main section 32 connected to the first end section 30 and the second end section 40. The main section 32 is located between the first end section 30 and the second end section 40. The first peaks 24 and first valleys 26 of the first end section 30 spread outward along the axial direction of the section 12 more than the first peaks 24 and first valleys 26 of the main section 32. The direction of extension of the first peaks 24 and first valleys 26 of the first end section 30 is closer to parallel to the axial direction of the section 12 than the direction of extension of the first peaks 24 and first valleys 26 of the main section 32. Similarly, the first peaks 24 and first valleys 26 of the second end cylindrical portion 40 extend outward along the axial direction of the cylindrical portion 12, more so than the first peaks 24 and first valleys 26 of the main cylindrical portion 32. The first peaks 24 and first valleys 26 of the second end cylindrical portion 40 are closer to being parallel to the axial direction of the cylindrical portion 12 than the extending direction of the first peaks 24 and first valleys 26 of the main cylindrical portion 32.
[0029] In the helical bellows section 22, multiple sets of first peaks 24 and first valleys 26 are arranged in a spiral pattern parallel to each other. For example, the number of sets of first peaks 24 and first valleys 26 is not particularly limited, but may be, for example, 5 to 25 sets. Here, 15 sets of first peaks 24 and first valleys 26 extend spirally around the cylindrical section 12, parallel to each other, forming the helical bellows section 22. As shown in Figures 1, 4, and 5, the 15 sets of first peaks 24 and first valleys 26 are arranged in the circumferential direction of the cylindrical section 12.
[0030] The number of times the first peak 24 and the first valley 26 circle around the cylindrical portion 12 from one end to the other of the helical bellows cylindrical portion 22 is not particularly limited, but may be, for example, one or more times and three or less times. In this case, the number of times the first peak 24 and the first valley 26 circle around the helical bellows cylindrical portion 22 from one end to the other is about one and a half times.
[0031] In the axial direction of the cylindrical portion 12, the lengths of the first cylindrical portion 14, the second cylindrical portion 20, the third cylindrical portion 18, the helical bellows cylindrical portion 22, the first connecting cylindrical portion 34, and the second connecting cylindrical portion 36 are not particularly limited and can be set as appropriate. For example, in the axial direction of the cylindrical portion 12, the helical bellows cylindrical portion 22 may be longer than the first cylindrical portion 14 and the first connecting cylindrical portion 34. For example, in the axial direction of the cylindrical portion 12, the helical bellows cylindrical portion 22 may occupy more than half of the length of the cylindrical portion 12.
[0032] Furthermore, in the spiral bellows section 22, each of the multiple first peaks 24 has a second peak 25 and a second valley 27. Each of the first peaks 24 has a plurality of alternating second peaks 25 and a plurality of second valleys 27. Each of the first peaks 24 has a plurality of alternating second peaks 25 and a plurality of second valleys 27 arranged at a constant pitch overall. Also, each of the multiple first valleys 26 has a second peak 25 and a second valley 27. Each of the first valleys 26 has a plurality of alternating second peaks 25 and a plurality of second valleys 27 arranged at a constant pitch overall. In this embodiment, as described above, each of the first peaks 24 and first valleys 26 has a second peak 25 and a second valley 27, but is not limited to this. Only a portion of the first peaks 24 or a portion of the first valleys 26 may have second peaks 25 and second valleys 27. In this embodiment, each of the first peaks 24 and first valleys 26 has a plurality of second peaks 25 and a plurality of second valleys 27 arranged alternately at a constant pitch, but is not limited to this. Each of the first peaks 24 and first valleys 26 may have a plurality of second peaks 25 and a plurality of second valleys 27 arranged alternately at an uneven pitch. In addition, one or both of the second peaks 25 and second valleys 27 may be provided as a single unit instead of multiple units.
[0033] Furthermore, as shown in Figure 4, the second peaks 25 adjacent to each other in the circumferential direction of the cylindrical portion 12 are provided in the same region E1 along the axial direction of the second cylindrical portion 20. Note that the second peaks 25 include those provided on the first peaks 24 and those provided on the first valleys 26. The second peaks 25 adjacent to region E1 in the axial direction of the cylindrical portion 12 are provided in the same region E2 along the axial direction of the second cylindrical portion 20. Regions E1 and E2 may be followed by region E3 along the axial direction of the second cylindrical portion 20. In addition, multiple further regions may be arranged along the axial direction of the second cylindrical portion 20.
[0034] Similarly, as shown in Figure 4, the second valleys 27 adjacent to each other in the circumferential direction of the cylindrical portion 12 are provided in the same region F1 along the axial direction of the second cylindrical portion 20. Note that the second valleys 27 include those provided in the first peaks 24 and those provided in the first valleys 26. The second valleys 27 adjacent to region F1 in the axial direction of the cylindrical portion 12 are provided in region F2 along the axial direction of the second cylindrical portion 20. Region F3 may be arranged following regions F1 and F2 along the axial direction of the second cylindrical portion 20. Furthermore, multiple regions may be arranged along the axial direction of the second cylindrical portion 20.
[0035] In this embodiment, the second peak section 25 has 10 regions arranged from region E1 to region E10. The second valley section 27 has 9 regions arranged from region F1 to region F9. The number of these regions is not particularly limited and can be set as appropriate. For example, the second peak section 25 may have 9 or fewer regions, or 11 or more regions. Similarly, the second valley section 27 may have 8 or fewer regions, or 10 or more regions. A larger number of regions increases flexibility, while a smaller number increases manufacturability.
[0036] In this embodiment, the second peak 25 and the second valley 27 are provided on the main cylindrical portion 32, but not on the first end cylindrical portion 30 and the second end cylindrical portion 40. However, the second peak 25 and the second valley 27 may be provided on the first end cylindrical portion 30 and the second end cylindrical portion 40. Also, in this embodiment, the second peak 25 and the second valley 27 are provided throughout the entire main cylindrical portion 32. However, the second peak 25 and the second valley 27 may be provided only on a part of the main cylindrical portion 32. For example, if the main cylindrical portion 32 has a first part and a second part which is arranged with a sharper bend than the first part, the second peak 25 and the second valley 27 may be provided only on the second part of the first part and the second part.
[0037] The wiring fixing portion 60 is provided at the other end of the cylindrical portion 12. The wiring fixing portion 60 is provided at the end of the helical bellows cylindrical portion 22 on the third cylindrical portion 18 side, opposite to the end on the first cylindrical portion 14 side. The wiring fixing portion 60 includes a plurality of (in this case, a pair) extension pieces 62. The plurality of extension pieces 62 are spaced apart from each other along the circumferential direction of the second cylindrical portion 20. Each of the plurality of extension pieces 62 protrudes axially from the tip of the helical bellows cylindrical portion 22. The thickness of the extension pieces 62 is substantially constant from the base end to the tip end. The distance between the pair of extension pieces 62 is substantially constant from the base end to the tip end. The extension pieces 62 do not have bellows sections, and the inner and outer surfaces of the extension pieces 62 are circumferentially shaped. A notch 28 is provided in the portion of the end of the helical bellows cylindrical portion 22 between the pair of extension pieces 62.
[0038] For example, with the wiring member 84 of the wire harness 82 passed through the grommet 10, the wiring member 84 and one end of the grommet 10 are fixed together by wrapping a fastening member such as adhesive tape or a cable tie around the wiring member 84 and the extension piece 62. The wiring fixing portion 60 may also be provided at the end on the first cylindrical portion 14 side.
[0039] As shown in Figure 2, the inner diameter of the first cylindrical portion 14 is larger than the inner diameter of the helical bellows cylindrical portion 22. It is preferable that the inner diameter of the portion of the first cylindrical portion 14 in which the fitting groove 16 is formed is larger than the inner diameter of the helical bellows cylindrical portion 22. Also, as shown in Figure 3, the inner diameter of the third cylindrical portion 18 is larger than the inner diameter of the helical bellows cylindrical portion 22. It is preferable that the inner diameter of the portion of the third cylindrical portion 18 in which the fitting groove 19 is formed is larger than the inner diameter of the helical bellows cylindrical portion 22. Of the inner diameters of the cylindrical portion 12, the inner diameter of the helical bellows cylindrical portion 22 is the smallest.
[0040] The spacing between the multiple extension pieces 62 is smaller than the inner diameter of the third cylindrical portion 18. Since the multiple extension pieces 62 are spaced apart in the circumferential direction and are not cylindrical, they are more easily expanded in diameter than the third cylindrical portion 18.
[0041] <Wire harness with grommet 80> The wire harness with grommet 80 comprises the grommet 10 and a wire harness 82 passed through the grommet 10.
[0042] The wire harness 82 includes a wiring member 84 and at least one connector 86 provided at the end of the wiring member 84. The wiring member 84 is, for example, an electric wire for transmitting electricity or an optical cable for transmitting light. Typically, multiple transmission members are bundled together to form the wiring member 84. The wiring member 84 passes through the grommet 10. The grommet 10 is attached to the middle portion of the wiring member 84. Hereinafter, the portion of the wiring member 84 to which the grommet 10 is attached will be referred to as the grommet attachment portion. At least one connector 86 is provided at the end of the wiring member 84 that is one end away from the grommet attachment portion.
[0043] For example, the wire harness 82 is passed through the grommet 10 from one end beyond the grommet mounting portion. In this case, the connector 86 of the wire harness 82 that is on one end beyond the grommet mounting portion needs to pass through the grommet 10 from one end to the other. In this case, if the inner diameter of the cylindrical portion 12 is smaller than the outer diameter of the connector 86, the grommet 10 needs to be deformed by expanding its diameter.
[0044] When there are a plurality of connectors 86 on one end side of the grommet mounting portion in the wire harness 82, if the outer dimension of the connector 86 and the inner diameter of the grommet 10 are set so that the largest connector 86 among the plurality of connectors 86 can pass through the grommet 10, the connectors 86 other than the largest connector 86 among the plurality of connectors 86 can also pass through the grommet 10. Note that since the other end side of the wire harness 82 than the portion mounted on the grommet 10 is not passed through the grommet 10, there is no need to consider the size of the connector 86.
[0045] Here, the inner diameter of the first cylindrical portion 14 may be larger than the outer dimension of the largest connector 86 among at least one connector 86. The outer dimension of the connector 86 is the largest dimension in the cross section of the connector 86. For example, when the connector 86 is in the shape of a rectangular parallelepiped, it is the dimension connecting two opposite corners among the four corners. The outer dimension of the connector 86 in this case is shown by the dimensions (outer dimension D) in FIGS. 2 and 3, for example. Thus, when the inner diameter of the first cylindrical portion 14 is larger than the outer dimension D of the largest connector 86 among at least one connector 86, the first cylindrical portion 14 does not need to be expanded in diameter when the connector 86 is inserted. Similarly to the first cylindrical portion 14, it is preferable that the first connecting cylindrical portion 34 also has a size that does not require diameter expansion when the connector 86 is inserted.
[0046] Also, the inner diameter of the third cylindrical portion 18 may be larger than the outer dimension D of the largest connector 86 among at least one connector 86. Thus, when the inner diameter of the third cylindrical portion 18 is larger than the outer dimension D of the largest connector 86 among at least one connector 86, the third cylindrical portion 18 does not need to be expanded in diameter when the connector 86 is inserted. Similarly to the third cylindrical portion 18, it is preferable that the second connecting cylindrical portion 36 also has a size that does not require diameter expansion when the connector 86 is inserted.
[0047] The outer dimension D of the connector 86 may be larger than the inner diameter of the helical bellows cylindrical portion 22. In this case, the helical bellows cylindrical portion 22 is expanded in diameter when passing the connector 86. For example, the helical bellows cylindrical portion 22 is expanded in diameter by the tip being twisted in the direction of the arrow B in FIGS. 1, 2, and 3.
[0048] The insertion of the wire harness 82 into the grommet 10 may be performed with the grommet 10 not attached to the vehicle body, or may be performed with the grommet 10 attached to the vehicle body. In the latter case, the wire harness 82 is inserted into the grommet 10 with the peripheral edge of the hole in the vehicle body panel fitted into the fitting groove 16. In this case, since the peripheral edge of the hole in the vehicle body panel is fitted into the fitting groove 16 in the portion of the first cylindrical portion 14 where the fitting groove 16 is formed, it is difficult to increase the diameter. Even in this case, since the inner diameter of the portion of the first cylindrical portion 14 where the fitting groove 16 is formed is larger than the outer dimension of the largest connector 86 among the connectors 86 passed through the grommet 10, the wire harness 82 can be passed through without substantially increasing the diameter of the first cylindrical portion 14. Similarly, since the peripheral edge of the hole in the vehicle body panel is fitted into the fitting groove 19 in the portion of the third cylindrical portion 18 where the fitting groove 19 is formed, it is difficult to increase the diameter. Even in this case, since the inner diameter of the portion of the third cylindrical portion 18 where the fitting groove 19 is formed is larger than the outer dimension of the largest connector 86 among the connectors 86 passed through the grommet 10, the wire harness 82 can be passed through without substantially increasing the diameter of the third cylindrical portion 18.
[0049] The thickness of the wiring member 84 is usually smaller than the outer dimension D of the connector 86. Therefore, if the grommet 10 has a size that allows the connector 86 to be inserted therethrough, the wiring member 84 can also be inserted therethrough. The wiring member 84 may be branched. In this case, it may be necessary to pass a branched line of a part of the wiring member 84 and a part of the connectors 86 through the grommet 10 at the same time. In this case, for example, the inner diameter of the portion of the first cylindrical portion 14 where the fitting groove 16 is formed may be set to be equal to or greater than the sum of the thickness of the branched line of the wiring member 84 and the dimension of the short side of the connector 86 to be passed through at the same time. Thereby, a branched line of a part of the wiring member 84 and a part of the connectors 86 can be passed through the grommet 10 at the same time without expanding and deforming the portion of the first cylindrical portion 14 where the fitting groove 16 is formed. Similarly, the inner diameter of the portion of the third cylindrical portion 18 where the fitting groove 19 is formed may be set to be equal to or greater than the sum of the thickness of the branched line of the wiring member 84 and the dimension of the short side of the connector 86 to be passed through at the same time. Thereby, a branched line of a part of the wiring member 84 and a part of the connectors 86 can be passed through the grommet 10 at the same time without expanding and deforming the portion of the third cylindrical portion 18 where the fitting groove 19 is formed.
[0050] The diameter of the grommet mounting portion of the wiring member 84 may be smaller than the inner diameter of the helical bellows portion 22. In this case, the grommet-equipped wire harness 80 may be held in a state of reduced diameter deformation of the helical bellows portion 22. For example, in the helical bellows portion 22, the end on the first cylindrical portion 14 side is twisted in the direction to the left of arrow B in Figure 2, and the end on the third cylindrical portion 18 side is twisted in the direction to the left of arrow B in Figure 3, thereby causing it to be reduced in diameter deformation. For example, the helical bellows portion 22 may be held in a reduced diameter deformation state by fixing the first cylindrical portion 14 and the third cylindrical portion 18 to the wiring member 84 while the helical bellows portion 22 is in a reduced diameter deformation state. The inner surface of the helical bellows portion 22 (the inner surface of the second valley portion 27 in the first valley portion 26) may be in close contact with the grommet mounting portion.
[0051] <Wire harness mounting structure 110> As shown in Figure 6, the wire harness mounting structure 110 comprises the grommet-equipped wire harness 80, a vehicle body panel 90 with a hole 91 formed therein, and a door panel 100 with a hole 101 formed therein. The vehicle body panel 90 is the part that faces the door opening. For example, a part of the vehicle body panel 90 different from the part with the hole 91 formed therein supports a door hinge connected to the door panel 100. The first cylindrical portion 14 engages with the peripheral edge of the hole 91 in the vehicle body panel 90, and the third cylindrical portion 18 engages with the peripheral edge of the hole 101 in the door panel 100. More specifically, the peripheral edge of the hole 91 formed in the vehicle body panel 90 fits into the fitting groove 16 of the first cylindrical portion 14 of the grommet 10. Also, the peripheral edge of the hole 101 formed in the door panel 100 fits into the fitting groove 19 of the third cylindrical portion 18 of the grommet 10.
[0052] The door panel 100 rotates as the door opens and closes. This causes the distance between the vehicle body panel 90 and the door panel 100 to increase or decrease. For example, when the door is in the closed position, the wire harness 82 and the helical bellows section 22 are bent and positioned so that the helical bellows section 22 fits through the narrow gap between the vehicle body panel 90 and the door panel 100. Specifically, holes 91 and 101 are formed at different positions in the vertical direction. When the door is in the closed position, as shown in Figure 6, sharp bends are formed in the helical bellows section 22 at positions P1 and P2. Position P1 is located at one end of the intermediate position P3 of the helical bellows section 22, and position P2 is located at the other end. The intermediate position P3 is a less curved section than positions P1 and P2. On the other hand, when the door is in the open position, the distance between hole 91 and hole 101 is greater than when the door is in the closed position. As a result, the cylindrical portion 12 is positioned in an elongated state, as shown in Figure 7.
[0053] In this embodiment, the extension and contraction of the second peak 25 and the second valley 27 suppresses buckling of the grommet 10 even when sharp bends are formed, such as at positions P1 and P2 when the door is in the closed position. More specifically, at position P1, the upper second peak 25 and the second valley 27 extend, and the lower second peak 25 and the second valley 27 contract. At position P2, the upper second peak 25 and the second valley contract, and the lower second peak 25 and the second valley 27 extend.
[0054] Furthermore, when the door is in the open position, the spiral bellows section 22 extends axially as a whole so that the height difference between the second peak 25 and the second valley 27 becomes smaller. This makes it easier to accommodate a larger distance between the holes 91 and 101 compared to the closed position by allowing the spiral bellows section 22 to extend axially.
[0055] In the above-described embodiment, the structure has a second peak 25 and a second valley 27 in which the first peak 24 and the first valley 26 are arranged alternately throughout, but the structure is not limited to this. For example, the structure may have a second peak 25 and a second valley 27 only in the locations corresponding to positions P1 and P2. Even with such a structure, buckling of the grommet 10 is suppressed even if a sharp bend is formed in the grommet 10.
[0056] Furthermore, although the above-described embodiment includes a third cylindrical portion 18, the invention is not limited thereto. For example, the third cylindrical portion 18 may be omitted, and a part of the wire harness 82 may be exposed from the second cylindrical portion 20 and connected to another wire harness via a connector or the like. In this case, the vehicle body panel to which the grommet is attached may be, for example, the dash panel. The dash panel separates the engine compartment from the passenger compartment in a vehicle. The wire harness 82 and the helical bellows cylindrical portion 22 may be bent and arranged so that the helical bellows cylindrical portion 22 weaves through narrow gaps in the engine compartment or passenger compartment. In this case, even if a sharp bend such as the position P1 described above is formed in the helical bellows cylindrical portion 22, buckling of the grommet is suppressed.
[0057] <Effects, etc.> With the grommet 10, wire harness 80 with grommet, and wire harness mounting structure 110 configured as described above, the helical bellows cylinder portion 22 can accommodate twisting along the circumferential direction by providing the first peak portion 24 and the first valley portion 26. More specifically, it can be deformed, including a change in its inner diameter, by being twisted along the circumferential direction. At this time, the helical bellows cylinder portion 22 can undergo expansion or contraction in diameter depending on the direction of twisting. For example, if the wiring member 84 or the connector 86 at the end of the wiring member 84 in the wire harness 82 is the same thickness as or thicker than the cylinder portion 12, the helical bellows cylinder portion 22 can be expanded in diameter to make it easier to pass the wire harness 82 through the cylinder portion 12. Furthermore, for example, if the wiring member 84 is thinner than the cylindrical portion 12, the spiral bellows portion 22 can be made to fit tightly against the outer circumference of the wiring member 84 by first passing the wiring member 84 through the cylindrical portion 12 and then reducing the diameter of the spiral bellows portion 22. Also, since the inner diameter of the first cylindrical portion 14 is larger than the inner diameter of the spiral bellows portion 22, it becomes easier to pass the wire harness 82 through the first cylindrical portion 14. As a result, it becomes easier to insert the wire harness 82 into the grommet 10.
[0058] Furthermore, the presence of the second peak 25 and the second valley 27 allows the helical bellows section 22 to accommodate axial bending. More specifically, the expansion and contraction of the second peak 25 and the second valley 27 reduces the load placed on the grommet 10 due to bending. Additionally, the expansion and contraction of the second peak 25 and the second valley 27 changes the length of the helical bellows section 22. Therefore, for example, even if the distance between the vehicle body panel to which one end of the grommet 10 engages and the vehicle body panel to which the other end engages changes, this can be accommodated by changing the length of the grommet 10.
[0059] Furthermore, each of the first peaks 24 and the first valleys 26 has a second peak 25 and a second valley 27. This further suppresses buckling when the helical bellows cylinder 22 bends.
[0060] Furthermore, each of the multiple first peaks 24 and first valleys 26 has multiple second peaks 25 and second valleys 27 arranged alternately. This allows for adaptation to the curved portion of the helical bellows cylinder 22 at multiple locations, and suppresses buckling of the grommet 10 at multiple locations. For example, even if the bending point of the helical bellows cylinder 22 changes, the second peaks 25 and second valleys 27 corresponding to the curved portion of the helical bellows cylinder 22 suppress buckling of the grommet 10.
[0061] Furthermore, the second peaks 25 adjacent to each other in the circumferential direction of the cylindrical portion 12 are provided in the same region along the axial direction of the second cylindrical portion 20. As a result, the second peaks 25 adjacent to each other in the circumferential direction of the cylindrical portion 12 are more easily bent along the axial direction of the second cylindrical portion 20. Therefore, buckling of the grommet 10 is suppressed.
[0062] Furthermore, the second valleys 27 adjacent to each other in the circumferential direction of the cylindrical portion 12 are provided in the same region along the axial direction of the second cylindrical portion 20. As a result, the second valleys 27 adjacent to each other in the circumferential direction of the cylindrical portion 12 are more easily bent along the axial direction of the second cylindrical portion 20. Therefore, buckling of the grommet 10 is suppressed.
[0063] [Note] With the first cylindrical portion 14 or the third cylindrical portion 18 attached to the vehicle body, the wire harness 82 can be passed through the grommet 10 by twisting or otherwise deforming the helical bellows cylindrical portion 22. This manufacturing method can be considered a manufacturing method for the wire harness mounting structure 110.
[0064] Furthermore, with the wire harness mounting structure 110 in place, a wiring member 84 with or without a connector 86 can be added by twisting or otherwise deforming the helical bellows cylinder portion 22. This method can be considered a method for adding a wire harness 82.
[0065] Furthermore, the configurations described in each of the above embodiments and modifications can be combined as appropriate, as long as they do not contradict each other.
[0066] 10 Grommet 12 Cylinder section 14 First cylinder section 16, 19 Fitting groove 18 Third cylinder section 20 Second cylinder section 22 Helical bellows cylinder section 24 First peak section 25 Second peak section 26 First valley section 27 Second valley section 28 Notch 30 First end cylinder section 32 Main cylinder section 34 First connecting cylinder section 36 Second connecting cylinder section 40 Second end cylinder section 60 Wiring fixing section 62 Extension piece 80 Wire harness with grommet 82 Wire harness 84 Wiring component 86 Connector 90 Body panel 91, 101 Hole 100 Door panel 110 Mounting structure A Extension direction B Arrow D Outer dimensions E1-E10 Area F1-F9 Area
Claims
1. A grommet comprising a cylindrical portion through which a wire harness is passed, wherein the cylindrical portion includes a first cylindrical portion having an engaging portion formed on its outer surface that engages with the peripheral edge of a hole in a vehicle body panel, and a second cylindrical portion communicating with the first cylindrical portion, wherein the second cylindrical portion includes a helical bellows cylindrical portion having a first peak and a first valley that extend helically around the axis of the cylindrical portion, and at least one of the first peak or the first valley has a second peak provided in a part along the extending direction of the helical extension, and a second valley provided in the other part along the extending direction.
2. A grommet according to claim 1, wherein each of the first peak and the first valley has a second peak and a second valley.
3. A grommet according to claim 1 or claim 2, wherein each of the first peaks and first valleys has a plurality of alternately arranged second peaks and second valleys.
4. A grommet according to claim 3, wherein the second peaks adjacent to each other in the circumferential direction of the cylindrical portion are provided in the same region along the axial direction of the second cylindrical portion.
5. A grommet according to claim 3, wherein the second valleys adjacent to each other in the circumferential direction of the cylindrical portion are provided in the same region along the axial direction of the second cylindrical portion.
6. A wire harness with a grommet, comprising: a grommet according to claim 1 or claim 2; and a wire harness passed through the grommet.
7. A wire harness mounting structure comprising: a wire harness with a grommet as described in claim 6; and a vehicle body panel having the hole formed therein, wherein the peripheral edge of the hole and the engaging portion of the grommet engage.