Grommet, wire harness with grommet, and mounting structure of wire harness

Abstract

The purpose of the present invention is to provide a technique capable of facilitating insertion of a wire harness into a grommet. The grommet is provided with a cylindrical part through which the wire harness is passed. The cylindrical part includes: a first cylindrical part having an outer surface on which a fitting groove into which a peripheral edge part of a hole of a vehicle body is fitted is formed; and a second cylindrical part communicating with the first cylindrical part. The second cylindrical part includes a spiral bellows cylindrical part in which a bellows part having a crest part and a trough part extends spirally around the axis of the cylindrical part. An inner diameter of the first cylindrical part is larger than an inner diameter of the spiral bellows cylindrical part.

Description

Grommet, grommet-equipped wire harness, and wiring harness mounting structure

[0001] The present disclosure relates to a grommet, a wire harness with a grommet, and a mounting structure for a wire harness.

[0002] Patent Document 1 discloses an automotive grommet that includes a pair of mounting portions and a bellows-shaped hollow cylindrical portion that connects the pair of mounting portions together via elbows, and a spiral portion having continuous helical peaks and valleys formed in the bellows-shaped hollow cylindrical portion. This grommet is attached between a door and a vehicle body. The bellows-shaped hollow cylindrical portion improves the grommet's ability to withstand twisting forces applied to it when the door is opened and closed, as well as its durability and waterproofness.

[0003] Japanese Patent Application Laid-Open No. 2007-157495

[0004] It is desirable to make it easy to insert the wire harness into the grommet.

[0005] Therefore, an object of the present invention is to provide a technique that can easily insert a wire harness into a grommet.

[0006] The grommet of the present disclosure comprises a tubular portion through which a wire harness is passed, the tubular portion including a first tubular portion having an engagement groove formed on its outer surface into which the peripheral edge of a hole in a vehicle body fits, and a second tubular portion communicating with the first tubular portion, the second tubular portion including a spiral bellows tubular portion having a bellows portion having peaks and valleys extending spirally around the axis of the tubular portion, and the inner diameter of the first tubular portion is larger than the inner diameter of the spiral bellows tubular portion.

[0007] According to the present disclosure, it is possible to easily insert a wire harness into a grommet.

[0008] Fig. 1 is a perspective view showing a grommet according to the first embodiment. Fig. 2 is a front view showing the same grommet. Fig. 3 is a plan view showing the same grommet. Fig. 4 is a side view showing the same grommet. Fig. 5 is a cross-sectional view taken along line V-V in Fig. 3. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 2. Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 2. Fig. 8 is a perspective view showing a grommet according to a first modified example. Fig. 9 is a perspective view showing a grommet according to a second modified example.

[0009] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described.

[0010] The grommet, the grommet-equipped wire harness, and the mounting structure of the wire harness according to the present disclosure are as follows.

[0011] (1) A grommet having a tubular portion through which a wire harness is passed, the tubular portion including a first tubular portion having a fitting groove formed on its outer surface into which the peripheral edge of a hole in a vehicle body fits, and a second tubular portion communicating with the first tubular portion, the second tubular portion including a spiral bellows tubular portion having a bellows portion having peaks and valleys extending spirally around the axis of the tubular portion, the inner diameter of the first tubular portion being larger than the inner diameter of the spiral bellows tubular portion.

[0012] According to the grommet (1), the spiral bellows tubular portion can be deformed by changing its inner diameter, for example, by being twisted circumferentially. At this time, the spiral bellows tubular portion can be deformed to expand or contract depending on the direction of twisting. For example, when the wiring member or the connector at the end of the wiring member in the wire harness is the same thickness as or thicker than the tubular portion, expanding the spiral bellows tubular portion can make it easier to pass the wire harness through the tubular portion. Furthermore, when the wiring member is thinner than the tubular portion, after passing the wiring member through the tubular portion, contracting the spiral bellows tubular portion can make the spiral bellows tubular portion tightly contact the outer periphery of the wiring member. Furthermore, because the inner diameter of the first tubular portion is larger than that of the spiral bellows tubular portion, it is also easy to pass the wire harness through the first tubular portion. These features facilitate insertion of the wire harness into the grommet.

[0013] (2) In the grommet of (1), the second tubular portion may include a connecting tubular portion that connects the first tubular portion and the spiral bellows tubular portion, and a circumferential groove may be formed on the outer surface of the connecting tubular portion.

[0014] (3) In the grommet of (2), the first tubular portion may include a protrusion protruding from an outer peripheral portion of an end face of the first tubular portion on the connecting tubular portion side, the connecting tubular portion may have a shape lacking a portion that overlaps with the protrusion, and the spiral bellows tubular portion may be provided on the inner peripheral side of the protrusion. By providing the spiral bellows tubular portion on the inner peripheral side of the protrusion, even if a protrusion is provided, interference between the protrusion and the spiral bellows tubular portion can be suppressed.

[0015] (4) In the grommet of any one of (1) to (3), the spiral bellows tubular portion may have an end tubular portion located at an end portion on the first tubular portion side and a main tubular portion connected to the end tubular portion, and the peaks and valleys of the end tubular portion may extend further outward in the axial direction of the tubular portion than the peaks and valleys of the main tubular portion, thereby making it easier to deform the main tubular portion in a concentrated manner when deforming the spiral bellows tubular portion.

[0016] (5) In any one of (1) to (4), the grommet may further include a wiring fixing portion provided at an end of the spiral bellows tubular portion opposite the end of the spiral bellows tubular portion adjacent to the first tubular portion, the wiring fixing portion including a plurality of extending pieces spaced apart from one another along the circumferential direction of the second tubular portion, each of the plurality of extending pieces protruding from the spiral bellows tubular portion. This allows, for example, a wiring member threaded through the grommet to be fastened to the wiring fixing portion by bundling the wiring fixing portion with the portion of the wiring member extending from one end of the grommet. Because the wiring fixing portion includes a plurality of extending pieces spaced apart from one another along the circumferential direction of the second tubular portion, the spiral bellows tubular portion can be easily twisted and deformed together with the wiring fixing portion, compared to a case in which the wiring fixing portion is cylindrical. Furthermore, because each of the plurality of extending pieces protrudes from the spiral bellows tubular portion, when the spiral bellows tubular portion is compressed, the inner surfaces of the extending pieces are deformed to approach each other.

[0017] (6) In the grommet of any one of (1) to (5), the inner diameter of the spiral bellows tubular portion may be the smallest among the inner diameters of the tubular portions. As a result, the portion of the tubular portion with the smallest inner diameter becomes the spiral bellows tubular portion, making it easier to expand the portion of the tubular portion with the smallest inner diameter and to pass the wire harness through the tubular portion.

[0018] (7) In any one of the grommets (1) to (6), the axial direction of the cylindrical portion may be along a single straight line from one end of the cylindrical portion to the other end of the cylindrical portion. This simplifies the structure of the grommet by simply passing it through a single hole, making it easier to insert the wire harness into the grommet.

[0019] (8) A grommet-equipped wire harness according to the present disclosure includes any one of the grommets (1) to (7) and a wire harness passed through the grommet.

[0020] (9) In the grommet-equipped wire harness of (8), the wire harness may include a wiring member passing through the grommet and at least one connector provided at an end of the wiring member closer to one end than the grommet, and the inner diameter of the first tubular portion may be larger than an outer dimension of a largest connector of the at least one connector. This allows even the largest connector to be passed through the first tubular portion without widening the first tubular portion.

[0021] (10) In the grommet-equipped wire harness of (8) or (9), the spiral bellows tubular portion may be held in a state of being deformed to reduce its diameter, thereby allowing the spiral bellows tubular portion to be in close contact with the wiring members of the wire harness therein.

[0022] (11) A mounting structure for a wire harness according to the present disclosure includes the grommet-equipped wire harness according to any one of (8) to (10) above, and a dash panel having a mounting hole formed therein, wherein a peripheral portion of the mounting hole is fitted into the fitting groove of the first cylindrical portion of the grommet. This allows the grommet to be easily attached to the wire harness, which is typically an engine room harness that does not move after being installed in a vehicle.

[0023] [Details of the embodiments of the present disclosure] Specific examples of the grommet, the grommet-equipped wire harness, and the mounting structure of the wire harness of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0024] [First Embodiment] Hereinafter, a grommet 10, a grommet-equipped wire harness 80, and a wire harness mounting structure 100 according to a first embodiment will be described. FIG. 1 is a perspective view showing the grommet 10 according to the first embodiment. FIG. 2 is a front view showing the grommet 10. FIG. 3 is a plan view showing the grommet 10. FIG. 4 is a side view showing the grommet 10. FIG. 5 is a cross-sectional view taken along line V-V in FIG. 3. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 2. FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 2. In FIGS. 2 to 7, a wire harness 82 is shown in phantom lines. Note that FIG. 7 shows the wire harness 82 in the middle of being inserted into the grommet 10. In addition, in FIGS. 4 to 7, a vehicle body panel 102 is shown in phantom lines.

[0025] The grommet 10 includes a tubular portion 12 through which a wire harness 82 is passed. In this embodiment, the grommet 10 includes a protrusion 40, a first wiring fixing portion 50, and a second wiring fixing portion 60. One or more of the protrusion 40, the first wiring fixing portion 50, and the second wiring fixing portion 60 may be omitted. The grommet 10 is formed of an elastic material such as rubber or elastomer. The grommet 10 is, for example, an injection-molded product formed using a mold.

[0026] The tubular portion 12 includes a first tubular portion 14 and a second tubular portion 20 that communicate with each other. A portion of the tubular portion 12 along the axial direction is the first tubular portion 14, and the other portion is the second tubular portion 20. The first tubular portion 14 is a portion that is attached to the vehicle body. A fitting groove 16 is formed on the outer surface of the first tubular portion 14. The fitting groove 16 fits into the peripheral edge of a hole in a vehicle body panel. The first tubular portion 14 protects the portion of the wire harness 82 that passes through the hole in the vehicle body panel from the peripheral edge of the hole. The second tubular portion 20 protects the portion of the wire harness 82 that extends from the hole in the vehicle body panel. In this embodiment, only one first tubular portion 14 is provided. The first tubular portion 14 forms one end of the tubular portion 12, and the second tubular portion 20 forms the other end of the tubular portion 12. In this embodiment, the axial direction of the tubular portion 12 follows a single straight line from one end to the other end of the tubular portion 12. The cylindrical portion 12 is formed in a straight line.

[0027] The second tubular portion 20 includes a spiral bellows tubular portion 22 and a connecting tubular portion 34. The spiral bellows tubular portion 22 is a tubular portion 12 in which a bellows portion having peaks 24 and valleys 26 extends spirally around the axis of the tubular portion 12. In the present disclosure, convex portions on the outer peripheral surface are referred to as peaks 24, and concave portions on the outer peripheral surface are referred to as valleys 26. On the inner peripheral surface, the relationship between the peaks 24 and valleys 26 on the outer peripheral surface is reversed. In other words, on the inner peripheral surface, the peaks 24 are concave, and the valleys 26 are convex. The connecting tubular portion 34 connects the first tubular portion 14 and the spiral bellows tubular portion 22. The connecting tubular portion 34 does not include a spiral bellows portion. A circumferential groove 36 is formed on the outer surface of the connecting tubular portion 34.

[0028] The spiral bellows tubular portion 22 has an end tubular portion 30 located at the end on the first tubular portion 14 side, and a main tubular portion 32 connected to the end tubular portion 30. The main tubular portion 32 continues to the end on the opposite side from the end tubular portion 30. The main tubular portion 32 forms the end of the tubular portion 12. The peaks 24 and valleys 26 of the end tubular portion 30 extend more radially outward than the peaks 24 and valleys 26 of the main tubular portion 32, while aligning more with the axial direction of the tubular portion 12. The extending direction of the peaks 24 and valleys 26 of the end tubular portion 30 is closer to being parallel to the axial direction of the tubular portion 12 than the extending direction of the peaks 24 and valleys 26 of the main tubular portion 32.

[0029] In the spiral bellows tubular portion 22, multiple sets of peaks 24 and valleys 26 are arranged parallel to one another in a spiral pattern. For example, the number of sets of peaks 24 and valleys 26 is not particularly limited, and may be, for example, 5 to 25 sets. Here, 15 sets of peaks 24 and valleys 26 extend parallel to one another in a spiral pattern around the tubular portion 12 to form the spiral bellows tubular portion 22. As shown in Fig. 5 , in a cross section of the spiral bellows tubular portion 22, the 15 sets of peaks 24 and valleys 26 are aligned in the circumferential direction.

[0030] The number of times that the peaks 24 and valleys 26 wrap around the tubular portion 12 from one end to the other of the spiral bellows tubular portion 22 is not particularly limited, but may be, for example, one to three times. Here, the number of times that the peaks 24 and valleys 26 wrap around the tubular portion 12 from one end to the other of the spiral bellows tubular portion 22 is about one and a half times.

[0031] The length dimensions of the first tubular portion 14, the second tubular portion 20, the spiral bellows tubular portion 22, and the connecting tubular portion 34 in the axial direction of the tubular portion 12 are not particularly limited and can be set as appropriate. For example, in the axial direction of the tubular portion 12, the spiral bellows tubular portion 22 may be longer than the first tubular portion 14 and the connecting tubular portion 34. For example, in the axial direction of the tubular portion 12, the spiral bellows tubular portion 22 may occupy more than half the length of the tubular portion 12.

[0032] The protrusion 40 protrudes from the outer peripheral portion of the end face of the first tubular portion 14 on the connecting tubular portion 34 side. The connecting tubular portion 34 has a shape that lacks a portion that overlaps with the protrusion 40. The spiral bellows tubular portion 22 is provided on the inner peripheral side of the protrusion 40.

[0033] The use of the protrusion 40 is not particularly limited. For example, the protrusion 40 may be gripped by an operator when attaching or detaching the grommet 10, or may be used for positioning the grommet 10. Furthermore, for example, as shown in FIG. 6 , the interior of the protrusion 40 may be hollow. In this case, by cutting off the tip of the protrusion 40, a wire such as a hood opener may be passed through the interior of the protrusion 40, or the tubular protrusion 40 may be used to connect a pipe such as a washer hose. The tubular protrusion 40 may pass through a hole in a vehicle body panel.

[0034] The first wiring fixing portion 50 is provided at one end of the tubular portion 12. The first wiring fixing portion 50 includes a plurality (here, a pair) of first extending pieces 52. The plurality of first extending pieces 52 are spaced apart from each other along the circumferential direction of the first tubular portion 14. The plurality of first extending pieces 52 protrude in the axial direction from the tip of the first tubular portion 14. The base ends of the first extending pieces 52 are thicker than the tip ends. The spacing between the pair of first extending pieces 52 at the base ends gradually narrows toward the tip ends. The spacing between the pair of first extending pieces 52 at the tip ends is constant.

[0035] The second wiring fixing portion 60 is provided at the other end of the tubular portion 12. The second wiring fixing portion 60 is provided at the end of the spiral bellows tubular portion 22 opposite the end on the first tubular portion 14 side. The second wiring fixing portion 60 includes multiple (here, a pair) second extending pieces 62. The multiple second extending pieces 62 are spaced apart from each other along the circumferential direction of the second tubular portion 20. Each of the multiple second extending pieces 62 protrudes axially from the tip of the spiral bellows tubular portion 22. The thickness of the second extending pieces 62 is approximately constant from the base end to the tip. The spacing between the pair of second extending pieces 62 is approximately constant from the base end to the tip. The second extending pieces 62 do not have a bellows portion, and the inner and outer surfaces of the second extending pieces 62 are circumferentially shaped. A notch 28 is provided in the end of the spiral bellows tubular portion 22, in a portion between the pair of second extending pieces 62.

[0036] For example, with the wiring member 84 of the wire harness 82 passed through the grommet 10, a bundling member such as adhesive tape or a cable tie is wrapped around the wiring member 84 and the pair of first extension pieces 52, thereby fixing the wiring member 84 to one end of the grommet 10. Similarly, a bundling member such as adhesive tape or a cable tie is wrapped around the wiring member 84 and the pair of second extension pieces 62, thereby fixing the other end of the wiring member 84 to the grommet 10.

[0037] 7, the inner diameter of the first tubular portion 14 is larger than the inner diameter of the spiral bellows tubular portion 22. The inner diameter of the portion of the first tubular portion 14 where the fitting groove 16 is formed is preferably larger than the inner diameter of the spiral bellows tubular portion 22. Of the inner diameters of the tubular portion 12, the inner diameter of the spiral bellows tubular portion 22 is the smallest.

[0038] The spacing between the multiple first extending pieces 52 is smaller than the inner diameter of the first tubular portion 14. The multiple first extending pieces 52 are spaced apart from one another in the circumferential direction and are not cylindrical, so they are more likely to expand in diameter than the first tubular portion 14. Similarly, the spacing between the multiple second extending pieces 62 is smaller than the inner diameter of the first tubular portion 14. The multiple second extending pieces 62 are spaced apart from one another in the circumferential direction and are not cylindrical, so they are more likely to expand in diameter than the first tubular portion 14.

[0039] <Grommet-Equipped Wire Harness 80 > The grommet-equipped wire harness 80 includes the grommet 10 and a wire harness 82 passed through the grommet 10 .

[0040] The wire harness 82 includes a wiring member 84 and at least one connector 86 provided at an 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, the wiring member 84 is formed by bundling a plurality of transmission members. The wiring member 84 passes through a grommet 10. The grommet 10 is attached to an intermediate portion of the wiring member 84. Hereinafter, the portion of the wiring member 84 where the grommet 10 is attached will be referred to as a grommet attachment portion. The at least one connector 86 is provided at an end of the wiring member 84 that is closer to one end than the grommet attachment portion.

[0041] For example, the wire harness 82 is passed through the grommet 10 from one end side of the grommet mounting portion. At this time, the connector 86 of the wire harness 82, which is on the one end side of the grommet mounting portion, needs to pass from one end to the other end of the grommet 10. At this time, if the inner diameter of the tubular portion 12 is smaller than the outer dimension of the connector 86, the grommet 10 needs to be deformed to expand in diameter.

[0042] When the wire harness 82 has multiple connectors 86 on one end side of the grommet mounting portion, if the outer dimensions of the connectors 86 and the inner diameter of the grommet 10 are set so that the largest connector 86 of the multiple connectors 86 can pass through the grommet 10, connectors 86 other than the largest connector 86 of the multiple connectors 86 can also pass through the grommet 10. Note that, because the other end side of the wire harness 82 from the portion mounted on the grommet 10 is not passed through the grommet 10, it is not necessary to consider the size of the connectors 86.

[0043] Here, the inner diameter of the first tubular portion 14 may be larger than the outer dimension of the largest connector 86 among the 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, if the connector 86 is rectangular parallelepiped, it is the dimension connecting two of the four corners that are opposite each other. In this case, the outer dimension of the connector 86 is indicated, for example, by dimension D in FIG. 2. In this way, if the inner diameter of the first tubular portion 14 is larger than the outer dimension D of the largest connector 86 among the at least one connector 86, the first tubular portion 14 does not need to expand or deform when the connector 86 is inserted. Like the first tubular portion 14, the connecting tubular portion 34 should also be sized so that expansion or deformation is not required when the connector 86 is inserted.

[0044] The outer dimension D of the connector 86 may be larger than the inner diameter of the spiral bellows tubular portion 22. In this case, the spiral bellows tubular portion 22 is expanded in diameter when the connector 86 is passed through it. For example, the spiral bellows tubular portion 22 is expanded in diameter by twisting the tip end in the direction of arrow A1 in FIG.

[0045] The wire harness 82 may be inserted into the grommet 10 while the grommet 10 is not attached to the vehicle body, or while the grommet 10 is 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 in the fitting groove 16. In this case, it is difficult to expand the diameter of the portion of the first tubular portion 14 where the fitting groove 16 is formed, because the peripheral edge of the hole in the vehicle body panel is fitted in the fitting groove 16. Even in this case, the inner diameter of the portion of the first tubular portion 14 where the fitting groove 16 is formed is larger than the outer dimensions of the largest connector 86 among the connectors 86 to be passed through the grommet 10, so the wire harness 82 can be passed through the first tubular portion 14 with almost no expansion of the diameter.

[0046] The thickness of the wiring member 84 is typically smaller than the outer dimension D of the connector 86. Therefore, as long as the grommet 10 is large enough to allow 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 some branched wires of the wiring member 84 and some connectors 86 through the grommet 10 at the same time. In this case, for example, the inner diameter of the portion of the first tubular portion 14 where the fitting groove 16 is formed may be equal to or greater than the sum of the thickness of the branched wires of the wiring member 84 to be passed through at the same time and the dimension of the short side of the connector 86. This allows some branched wires of the wiring member 84 and some connectors 86 to be passed through the grommet 10 at the same time without enlarging or deforming the portion of the first tubular portion 14 where the fitting groove 16 is formed.

[0047] The diameter of the grommet mounting portion of the wiring member 84 may be smaller than the inner diameter of the spiral bellows tube portion 22. In this case, in the grommet-equipped wire harness 80, the spiral bellows tube portion 22 may be held in a diameter-reduced deformed state. For example, the spiral bellows tube portion 22 is deformed in a diameter-reduced state by twisting the tip end portion in the direction of arrow A2 in FIG. 1 . For example, the spiral bellows tube portion 22 may be held in a diameter-reduced deformed state by fixing the second wiring fixing portion 60 to the wiring member 84 while the spiral bellows tube portion 22 is deformed in a diameter-reduced state. The inner surface of the spiral bellows tube portion 22 (the inner surface of the valley portion 26) may be in close contact with the grommet mounting portion.

[0048] <Wire harness mounting structure 100> The wire harness mounting structure 100 includes the grommet-equipped wire harness 80 and a vehicle body panel in which a mounting hole 104 is formed. In this example, an example is described in which the vehicle body panel is a dash panel 102. The vehicle body panel may be a panel other than the dash panel 102. The peripheral portion of the mounting hole 104 formed in the dash panel 102 is fitted into the fitting groove 16 of the first tubular portion 14 of the grommet 10.

[0049] The dash panel 102 is a panel that separates the passenger compartment from an engine compartment located forward of the passenger compartment. The dash panel 102 extends generally along a plane including the vehicle width direction and the vertical direction. The grommet 10 penetrates the dash panel 102. In this case, the grommet 10 may be oriented so that the spiral bellows tubular portion 22 is disposed in the engine compartment, or may be oriented so that the grommet is disposed in the passenger compartment. In the former case, the wire harness 82 and the spiral bellows tubular portion 22 may be curved so as to thread through a narrow gap in the engine compartment. In the latter case, the wire harness 82 and the spiral bellows tubular portion 22 may be curved so as to thread through a narrow gap between the dash panel 102 and the instrument panel in the passenger compartment.

[0050] <Effects, etc.> With the grommet 10, grommet-equipped wire harness 80, and wire harness mounting structure 100 configured as described above, the spiral bellows tubular portion 22 can be deformed, changing its inner diameter, by being twisted, for example, in the circumferential direction. At this time, the spiral bellows tubular portion 22 can be deformed to expand or contract 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 tubular portion 12, expanding the spiral bellows tubular portion 22 can make it easier to pass the wire harness 82 through the tubular portion 12. Furthermore, for example, if the wiring member 84 is thinner than the tubular portion 12, after passing the wiring member 84 through the tubular portion 12, contracting the spiral bellows tubular portion 22 can bring the spiral bellows tubular portion 22 into intimate contact with the outer periphery of the wiring member 84. Furthermore, since the inner diameter of the first tubular portion 14 is larger than the inner diameter of the spiral bellows tubular portion 22, it is also easy to pass the wire harness 82 through the first tubular portion 14. This makes it easy to insert the wire harness 82 into the grommet 10.

[0051] The second tubular portion 20 also includes a connecting tubular portion 34 that connects the first tubular portion 14 and the spiral bellows tubular portion 22, and a circumferential groove 36 is formed on the outer surface of the connecting tubular portion 34. This makes it difficult for the force that twists and deforms the spiral bellows tubular portion 22 to be transmitted to the first tubular portion 14.

[0052] Furthermore, the spiral bellows tube portion 22 is provided on the inner peripheral side of the protrusion portion 40. This makes it possible to suppress interference between the protrusion portion 40 and the spiral bellows tube portion 22 even when the protrusion portion 40 is provided.

[0053] Furthermore, the peaks 24 and valleys 26 of the end tubular portion 30 extend further outward in the axial direction of the tubular portion 12 than the peaks 24 and valleys 26 of the main tubular portion 32. This makes it easier to deform the main tubular portion 32 in a concentrated manner when deforming the spiral bellows tubular portion 22.

[0054] Furthermore, each of the multiple extension pieces in the wiring fixing portion protrudes from the spiral bellows tubular portion 22. As a result, for example, by bundling the wiring member 84 threaded through the grommet 10 with the wiring fixing portion, it is possible to fix the portion of the wiring member 84 extending from one end of the grommet 10 to the wiring fixing portion. Because the wiring fixing portion includes multiple extension pieces that are spaced apart from each other along the circumferential direction of the second tubular portion 20, it is easier to twist and deform the spiral bellows tubular portion 22 together with the wiring fixing portion, compared to when the wiring fixing portion is cylindrical. Furthermore, because each of the multiple extension pieces protrudes from the spiral bellows tubular portion 22, when the spiral bellows tubular portion 22 is deflated, the inner surfaces of the extension pieces deform so as to approach each other.

[0055] Furthermore, the inner diameter of the spiral bellows tubular portion 22 is the smallest among the inner diameters of the tubular portion 12. As a result, the portion of the tubular portion 12 with the smallest inner diameter becomes the spiral bellows tubular portion 22, making it easier to expand the portion of the tubular portion 12 with the smallest inner diameter, and making it easier to pass the wire harness 82 through the tubular portion 12.

[0056] In addition, the axial direction of the tubular portion 12 is along a single straight line from one end to the other end of the tubular portion 12. This results in a simple structure in which the grommet 10 simply passes through a single hole, making it easy to insert the wire harness 82 into the grommet 10.

[0057] Furthermore, in the grommet-equipped wire harness 80, the inner diameter of the first tubular portion 14 is larger than the outer dimension of the largest connector 86 among the at least one connector 86. This allows the largest connector 86 to be passed through the first tubular portion 14 without widening the first tubular portion 14.

[0058] Furthermore, when the spiral bellows tube portion 22 is held in a state in which its diameter is reduced and deformed, the spiral bellows tube portion 22 can be in close contact with the wiring member 84 of the wire harness 82 therein.

[0059] Furthermore, according to the wire harness mounting structure 100, the peripheral portion of the mounting hole 104 formed in the dash panel 102 fits into the fitting groove 16 of the first tubular portion 14 of the grommet 10. This allows the grommet 10 to be easily attached to the wire harness 82, which is an engine room harness that does not normally move after being placed in the vehicle.

[0060] [Note] With the first tubular portion 14 attached to the vehicle body, the wire harness 82 can be passed through the grommet 10 by deforming the spiral bellows tubular portion 22, for example by twisting it. This manufacturing method can be considered as a manufacturing method for the mounting structure 100 for the wire harness.

[0061] Furthermore, in a state where the wire harness mounting structure 100 is in place, it is possible to add a wiring member 84 with or without a connector 86 by twisting or otherwise deforming the spiral bellows tube portion 22. This method can be regarded as a method of adding a wire harness 82.

[0062] 8 is a perspective view showing a grommet 110 according to a first modified example. The grommet 110 differs from the grommet 10 in that the protrusion 40 is omitted. The grommet 110 has the same configuration as the grommet 10, except for the omission of the protrusion 40 and other associated features. In the grommet 110, the same components as those in the grommet 10 are designated by the same reference numerals, and their description will be omitted. The same applies to the following modified examples. In the case where the protrusion 40 is omitted as in the grommet 110, the connecting tubular portion 34 may be completely circular.

[0063] FIG. 9 is a perspective view showing a grommet 210 according to a second modification. The grommet 210 differs from the grommet 10 in that the first tubular portions 14 are provided at both ends of the second tubular portion 20. In the grommet 210, the two first tubular portions 14 are each attached to a panel. The panels to which the two first tubular portions 14 are attached may be, for example, different panels of a vehicle. In this case, the second tubular portion 20 spans between the two panels. For example, one of the two first tubular portions 14 may be attached to a door panel, and the other first tubular portion 14 may be attached to a body panel. In this case, the second tubular portion 20 may deform when the door is opened or closed. The first wiring fixing portion 50 is provided on only one of the two first tubular portions 14. The first wiring fixing portion 50 may also be provided on both of the two first tubular portions 14.

[0064] The configurations described in the above embodiments and modifications can be combined as appropriate as long as they are not mutually contradictory.

[0065] REFERENCE SIGNS LIST 10, 110, 210 Grommet 12 Cylindrical portion 14 First cylindrical portion 16 Fitting groove 20 Second cylindrical portion 22 Spiral bellows cylindrical portion 24 Peak portion 26 Valley portion 28 Notch 30 End cylindrical portion 32 Main cylindrical portion 34 Connecting cylindrical portion 36 Circumferential groove 40 Projection portion 50 First wiring fixing portion 52 First extending piece 60 Second wiring fixing portion 62 Second extending piece 80 Wire harness with grommet 82 Wire harness 84 Wiring member 86 Connector 100 Wire harness mounting structure 102 Dash panel 104 Mounting hole

Claims

1. A grommet comprising: a tubular portion through which a wire harness is passed, the tubular portion including a first tubular portion having an engagement groove formed on its outer surface into which the peripheral portion of a hole in a vehicle body fits, and a second tubular portion communicating with the first tubular portion, the second tubular portion including a spiral bellows tubular portion having a bellows portion having peaks and valleys extending spirally around the axis of the tubular portion, the inner diameter of the first tubular portion being larger than the inner diameter of the spiral bellows tubular portion.

2. A grommet as claimed in claim 1, wherein the second tubular portion includes a connecting tubular portion that connects the first tubular portion and the spiral bellows tubular portion, and a circumferential groove is formed on the outer surface of the connecting tubular portion.

3. A grommet as claimed in claim 2, comprising a protrusion protruding from an outer peripheral portion of the end face of the first tubular portion on the connecting tubular portion side, the connecting tubular portion having a shape lacking a portion that overlaps with the protrusion, and the spiral bellows tubular portion being provided on the inner peripheral side of the protrusion.

4. A grommet as claimed in any one of claims 1 to 3, wherein the spiral bellows tubular portion has an end tubular portion located at the end on the first tubular portion side, and a main tubular portion connected to the end tubular portion, and the peaks and valleys of the end tubular portion extend further outwardly than the peaks and valleys of the main tubular portion while following the axial direction of the tubular portion.

5. A grommet as claimed in any one of claims 1 to 3, comprising a wiring fixing portion provided at an end of the spiral bellows tubular portion opposite the end on the first tubular portion side, the wiring fixing portion including a plurality of extending pieces spaced apart from one another along the circumferential direction of the second tubular portion, each of the plurality of extending pieces protruding from the spiral bellows tubular portion.

6. A grommet according to any one of claims 1 to 3, wherein the inner diameter of the spiral bellows cylindrical portion is the smallest among the inner diameters of the cylindrical portions.

7. A grommet according to any one of claims 1 to 3, wherein the axial direction of the cylindrical portion is along a single straight line from one end of the cylindrical portion to the other end.

8. A grommet-attached wire harness comprising: the grommet according to any one of claims 1 to 3; and a wire harness passed through the grommet.

9. A grommet-equipped wire harness as described in claim 8, comprising a wiring member passing through the grommet and at least one connector provided at an end of the wiring member closer to one end than the grommet, and the inner diameter of the first tubular portion is larger than the outer dimension of the largest connector of the at least one connector.

10. A grommet-equipped wire harness according to claim 8, wherein the spiral bellows tubular portion is held in a radially contracted and deformed state.

11. A mounting structure for a wire harness, comprising: a grommet-equipped wire harness as claimed in claim 8; and a dash panel having a mounting hole formed therein, wherein the peripheral portion of the mounting hole is fitted into the mating groove of the first tubular portion of the grommet.

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