Wire harness
The grommet's variable portions enable manual expansion and contraction, simplifying attachment and reducing damage, enhancing the productivity and sealing of wire harnesses.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- YAZAKI CORP
- Filing Date
- 2024-12-18
- Publication Date
- 2026-06-30
AI Technical Summary
The use of dedicated devices to expand the diameter of grommets for wire harnesses complicates the attachment process, reduces productivity, and can cause damage to the grommets due to excessive expansion.
A grommet with a cylindrical portion featuring a first variable portion recessed in a groove shape and a second variable portion extending continuously, allowing manual expansion and contraction without dedicated tools, and secured with a tape for close contact with the wire.
Facilitates easy attachment of the grommet to the wire harness, reduces damage risk, and enhances sealing performance by manual expansion and contraction, improving overall productivity and versatility.
Smart Images
Figure 2026107271000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a wire harness including an electric wire, a grommet attached to the electric wire, and a fixture attached to the grommet.
Background Art
[0002] Conventionally, for example, when routing a wire harness so as to penetrate a body panel (e.g., a dash panel or the like) that partitions the inside and outside of a vehicle cabin, a grommet for closing a gap between a through-hole of the body panel and a wire bundle of the wire harness is attached to the wire bundle from the viewpoints of waterproofing, soundproofing, etc. (see, for example, Patent Document 1).
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] When attaching a grommet of the above-described type to a wire bundle, usually, a dedicated device (so-called, an expander) is used to elastically expand the diameter of a cylindrical portion, and the wire bundle is inserted into the expanded cylindrical portion. This is because it is difficult for an operator to manually expand the diameter of the cylindrical portion in consideration of the elastic modulus, shape, etc. of the cylindrical portion. However, the need for such a dedicated device can hinder the workability of the operation of attaching the grommet to the wire bundle (and thus the productivity of the wire harness), and in some cases, the cylindrical portion may be damaged due to excessive diameter expansion. For these reasons, it is desired to improve the productivity of the wire harness by using a grommet having excellent workability in the operation of inserting an electric wire into the cylindrical portion.
[0005] One object of the present invention is to provide a wire harness having excellent productivity. [Means for solving the problem]
[0006] To achieve the aforementioned objectives, the wire harness according to the present invention has the following features.
[0007] A wire harness comprising an electric wire, a grommet attached to the electric wire, and a fastener attached to the grommet, The grommet is, It has a cylindrical portion that is elastically deformable in the radial direction and through which the electric wire is inserted, and a main body portion that extends from the cylindrical portion and is fitted into a through hole in the object to be attached, The aforementioned cylindrical portion is The cylindrical portion has a first variable portion which is configured such that a part of the cylindrical wall of the cylindrical portion is recessed in a groove-like shape toward the radially outward direction and extends along the cylindrical axis of the cylindrical portion, The main body is, It has a second variable portion that extends continuously with the first variable portion and is configured such that a part of the main body portion is recessed in a groove shape, The aforementioned fixing device is The first variable part is deformed to conform to the outer circumferential surface of the cylindrical part, and is attached to the cylindrical part. It must be a wire harness. [Effects of the Invention]
[0008] According to the wire harness of the present invention, the cylindrical portion of the grommet is provided with a first variable portion configured such that a part of the cylindrical portion is grooved outward in the radial direction and extends along the cylindrical axis of the cylindrical portion, and the main body of the grommet is provided with a second variable portion configured to extend continuously with the first variable portion and be grooved. As a result, when the first variable portion is deformed so as to separate a pair of groove walls of the first variable portion that face each other in the circumferential direction of the cylindrical portion, the diameter of the cylindrical portion expands, and when the first variable portion is deformed so as to bring the pair of groove walls closer together, the diameter of the cylindrical portion contracts. The second variable portion deforms in conjunction with the deformation of the first variable portion, as its pair of groove walls move in conjunction with the deformation of the first variable portion. Due to the operation of the first and second variable portions in this way, the cylindrical portion can be easily expanded and contracted by the operator by hand without the use of a dedicated device (expanding machine). As a result, the work of attaching the grommet to the electric wire can be made easier, and the possibility of damage to the cylindrical portion due to excessive expansion can be reduced. Furthermore, after passing the electric wire through the cylindrical section, the first variable section is deformed using a fixing device (e.g., tape) to conform to the outer surface of the cylindrical section, and the fixing device is then attached to the cylindrical section. This ensures that the cylindrical section remains in close contact with the electric wire. Therefore, the wire harness of the present invention offers excellent productivity.
[0009] The present invention has been briefly described above. Further details of the present invention will be clarified by referring to the accompanying drawings and reading through the embodiments for carrying out the invention described below. [Brief explanation of the drawing]
[0010] [Figure 1] Figure 1 is a perspective view of a wire harness according to an embodiment of the present invention. [Figure 2] Figure 2 is a front view of the wire harness shown in Figure 1. [Figure 3] Figure 3 is a top view of the grommet that makes up the wire harness shown in Figure 1. [Figure 4] Figure 4 is a top view corresponding to Figure 3, showing the state in which the first variable part is deformed to enlarge the diameter of the cylindrical part in order to insert the wire bundle through it. [Figure 5] Figure 5 is a top view corresponding to Figure 3, showing the state in which tape is wrapped around the cylindrical part through which the wire bundle is inserted. [Figure 6] Figure 6 is a diagram corresponding to Figure 2 in another embodiment of the present invention. [Modes for carrying out the invention]
[0011] <Embodiment> Hereinafter, a wire harness 4 according to an embodiment of the present invention will be described with reference to the drawings. As shown in Figures 1 and 2, the wire harness 4 comprises a wire bundle 2, a grommet 1 attached to the wire bundle 2, and a tape 3 wrapped around the grommet 1. The grommet 1 constituting the wire harness 4 is typically used by being attached to a through-hole Pa (see Figure 2) in the vehicle body panel P to seal the gap between the through-hole Pa in the vehicle body panel P and the wire bundle 2 when the wire bundle 2 constituting the wire harness 4 is routed to pass through a vehicle body panel P (e.g., a dash panel) that separates the inside and outside of the passenger compartment of an automobile, as shown in Figures 1 and 2.
[0012] For the sake of explanation, the terms "front," "rear," "left," "right," "up," and "down" are defined below, as shown in Figure 1, etc. The "up" side corresponds to the inside of the passenger compartment relative to the vehicle body panel P, and the "down" side corresponds to the outside of the passenger compartment relative to the vehicle body panel P. In other words, the "up and down direction" can be rephrased as the "inside and outside direction." The "up and down direction," "left and right direction," and "front and rear direction" are orthogonal to each other. Note that the "up and down direction," "left and right direction," and "front and rear direction" are defined solely for the sake of explanation and do not necessarily have to correspond to the up and down, left and right, and front and rear directions of the vehicle when the grommet 1 is mounted on the vehicle.
[0013] The grommet 1, which constitutes the wire harness 4, is a molded product made of an elastic material (for example, rubber), and as shown in Figures 1 and 2, it integrally comprises a main body portion 10 and a cylindrical portion 20. The configuration of each part constituting the grommet 1 will be described in order below.
[0014] First, the main body part 10 will be described. The main body part 10 is a part that will be fitted into the through-hole Pa of the vehicle body panel P. As shown in FIGS. 1 and 2, the main body part 10 includes a cylindrical base part 11 extending in the vertical direction, a tapered cylindrical first upper protrusion part 12 that is continuous with the upper end of the base part 11 and gradually decreases in diameter at a first inclination angle as it moves upward from the base part 11, and a tapered cylindrical second upper protrusion part 13 that is continuous with the upper end of the first upper protrusion part 12 and gradually decreases in diameter at a second inclination angle larger than the first inclination angle as it moves upward from the first upper protrusion part 12. An annular engagement groove 11a that will be fitted into the through-hole Pa of the vehicle body panel P is formed on the outer peripheral side surface of the base part 11.
[0015] Next, the cylindrical part 20 will be described. The cylindrical part 20 is a substantially cylindrical part that extends upward from the upper end of the second upper protrusion part 13 of the main body part 10 and through which the wire bundle 2 will be inserted. The cylindrical part 20 is elastically deformable in the radial direction. The internal space of the cylindrical part 20 communicates with the internal space of the main body part 10.
[0016] As shown in FIGS. 1 and 2, a first variable part 21 is provided on the cylindrical part 20. The first variable part 21 is recessed (projected in a protrusion shape) in a groove shape toward the outside in the radial direction (that is, the outside of the cylindrical part 20) at one position in the circumferential direction of the cylindrical wall constituting the cylindrical part 20, and extends straight along the cylindrical axis direction (that is, the vertical direction) over the entire range in the cylindrical axis direction from the tip (that is, the upper end) to the base end (that is, the lower end) of the cylindrical part 20. As shown in FIG. 3, the wall thickness of a pair of groove walls 22 that face each other in the circumferential direction of the cylindrical part 20 and constitute the first variable part 21 is smaller than the wall thickness of the cylindrical wall constituting the cylindrical part 20 at a location different from the first variable part 21. In other words, the first variable part 21 has a thin-walled structure in which the thickness of the first variable part 21 is smaller than the thickness at a location different from the first variable part 21 in a cross section perpendicular to the cylindrical axis of the cylindrical part 20.
[0017] In correspondence with the provision of the first variable portion 21 in the cylindrical portion 20, a second variable portion 14 is also provided in the second upward projecting portion 13 of the main body portion 10 as shown in FIGS. 1 and 2. The second variable portion 14 is recessed (projected in a protruding shape) in a groove shape toward the outside (the outer side of the main body portion 10) at the same circumferential location as the circumferential location where the first variable portion 21 is provided in the tapered cylindrical wall constituting the second upward projecting portion 13, and extends straight along the direction orthogonal to the circumferential direction over the entire region from the upper end to the lower end of the second upward projecting portion 13. The second variable portion 14 extends continuously from the lower end of the first variable portion 21. In other words, each of the pair of groove walls 15 (see FIGS. 2 and 3) that face each other in the circumferential direction of the second upward projecting portion 13 and constitute the second variable portion 14 is continuous with each of the pair of groove walls 22 constituting the first variable portion 21. The wall thickness of the pair of groove walls 15 is smaller than the wall thickness of the tapered cylindrical wall constituting the second upward projecting portion 13 at a location different from the second variable portion 14. In other words, the second variable portion 14 has a thin-walled structure in which the thickness of the second variable portion 14 is smaller than the thickness at a location different from the second variable portion 14 in a cross section orthogonal to the cylindrical axis of the second upward projecting portion 13.
[0018] As described above, by providing the first variable portion 21 in the cylindrical portion 20 and providing the second variable portion 14 continuous from the first variable portion 21 in the second upward projecting portion 13 of the main body portion 10, when the first variable portion 21 is deformed so as to bring the pair of groove walls 22 of the first variable portion 21 closer to each other, the diameter of the cylindrical portion 20 is reduced, and when the first variable portion 21 is deformed so as to separate the pair of groove walls 22 from each other (see FIG. 4), the diameter of the cylindrical portion 20 is increased. At that time, the second variable portion 14 is deformed so that the pair of groove walls 15 interlocks with the deformation of the first variable portion 21. Specifically, when the first variable portion 21 is deformed so that the pair of groove walls 22 approach each other, the second variable portion 14 is deformed so that the pair of groove walls 15 approach each other, and when the first variable portion 21 is deformed so that the pair of groove walls 22 separate from each other, the second variable portion 14 is deformed so that the pair of groove walls 15 separate from each other. Here, since each of the first variable portion 21 and the second variable portion 14 has the thin-walled structure as described above, it becomes easier to deform the first variable portion 21 and the second variable portion 14.
[0019] In grommet 1, the first variable part 21 and the second variable part 14, as described above, allow the cylindrical part 20 to be easily expanded and contracted by the worker's manual operation without the need for a dedicated device (a so-called expansion machine). As a result, the work of attaching grommet 1 to the wire bundle 2 is made easier, and the possibility of damage to the cylindrical part 20 due to excessive expansion is also reduced.
[0020] Furthermore, another benefit is that the versatility of the grommet 1 can be improved. Specifically, because the diameter of the cylindrical portion 20 can be easily expanded and contracted, the single-shaped grommet 1 can be attached to both thin and thick wire bundles 2. In other words, the upper and lower limits of the wire bundle 2's thickness that can be properly inserted into the cylindrical portion 20 (i.e., the range in which the cylindrical portion 20 can absorb differences in wire bundle thickness) can be expanded compared to conventional grommets. The configuration of each part constituting the grommet 1 has been explained above.
[0021] A wire bundle 2 is inserted through the grommet 1 having the above configuration (see Figures 1 and 2). Depending on the specifications of the vehicle on which the wire bundle 2 is mounted, the thickness of the wire bundle 2 inserted through the grommet 1 may vary. When inserting the wire bundle 2 into the grommet 1, without using a special device (so-called expansion machine), the worker manually deforms the first variable part 21 so that the pair of groove walls 22 of the first variable part 21 are separated from each other, maintaining a state in which the cylindrical part 20 is expanded in diameter (see Figure 4). The wire bundle 2 is then inserted into the grommet 1 by inserting it into the internal space of the cylindrical part 20 from the open end (upper end) side of the cylindrical part 20 or the open end (lower end) side of the main body part 10.
[0022] After the wire bundle 2 is inserted into the grommet 1, the manually expanded state of the cylindrical portion 20 is released. As a result, the first variable portion 21 elastically recovers so that the pair of groove walls 22 move closer to each other, and the cylindrical portion 20 shrinks in diameter, causing the inner wall surface of the cylindrical portion 20 to adhere closely to the outer surface of the wire bundle 2. This enables the sealing performance of the cylindrical portion 20. Next, the tape 3 is wrapped around the cylindrical portion 20 (see Figure 5). The tape 3 corresponds to the "fixing device" of the present invention. Specifically, with the pair of groove walls 22 constituting the first variable portion 21 overlapping each other, the first variable portion 21 is tilted toward one side in the circumferential direction of the cylindrical portion 20 and deformed to follow the outer surface of the cylindrical portion 20, while the tape 3 is wrapped only around the cylindrical portion 20. By wrapping the tape 3 in this way, the state in which the cylindrical portion 20 adheres closely to the wire bundle 2 can be properly maintained. This further improves the sealing performance of the cylindrical portion 20. Thus, the wire harness 4 shown in Figures 1 and 2 is completed, comprising a wire bundle 2, a grommet 1 attached to the wire bundle 2, and a tape 3 wrapped around the grommet 1.
[0023] As shown in Figures 1 and 2, the grommet 1 through which the wire bundle 2, which constitutes the completed wire harness 4, is inserted is attached to the through-hole Pa of the vehicle body panel P by fitting the engagement groove 11a of the main body portion 10 into the through-hole Pa of the vehicle body panel P. As a result, the gap between the wire bundle 2, which is routed to pass through the through-hole Pa of the vehicle body panel P, and the through-hole Pa is sealed by the grommet 1 (specifically the cylindrical portion 20), thereby achieving the waterproof function (sealing performance) of the grommet 1.
[0024] <Effects and Actions> As described above, according to the wire harness 4 of this embodiment, the cylindrical portion 20 of the grommet 1 is provided with a first variable portion 21 which is grooved outward in a part of the cylindrical portion 20 and extends along the cylindrical axis of the cylindrical portion 20, and the main body portion 10 of the grommet 1 is provided with a second variable portion 14 which extends continuously with the first variable portion 21 and is grooved. As a result, when the first variable portion 21 is deformed so that the pair of groove walls 22 of the first variable portion 21 that face each other in the circumferential direction of the cylindrical portion 20 are separated from each other, the diameter of the cylindrical portion 20 is expanded, and when the first variable portion 21 is deformed so that the pair of groove walls 22 are brought closer together, the diameter of the cylindrical portion 20 is reduced. The second variable portion 14 is deformed so that its pair of groove walls 15 are linked to the deformation of the first variable portion 21. The functions of the first variable section 21 and the second variable section 14 allow the cylindrical section 20 to be easily expanded and contracted by the operator's manual labor without the need for a dedicated device (expanding machine). As a result, the work of attaching the grommet 1 to the wire bundle 2 is simplified, and the possibility of damage to the cylindrical section 20 due to excessive expansion is reduced. Furthermore, after passing the wire bundle 2 through the cylindrical section 20, the tape 3 is wrapped around the cylindrical section 20 while deforming the first variable section 21 to conform to the outer surface of the cylindrical section 20. This ensures that the cylindrical section 20 is properly in close contact with the wire bundle 2. Therefore, the grommet 1 according to this embodiment offers excellent productivity.
[0025] Furthermore, according to the wire harness 4 of this embodiment, the first variable portion 21 has a thin-walled structure in which the thickness of the first variable portion 21 is smaller than the thickness of other portions. This makes it even easier to deform the first variable portion 21 when inserting the wire bundle 2 into the cylindrical portion 20.
[0026] Furthermore, according to the wire harness 4 of this embodiment, the tape 3 is wrapped only around the cylindrical portion 20 of the grommet 1. This ensures that the cylindrical portion 20 remains in close contact with the wire bundle 2.
[0027] <Other embodiments> It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the embodiments described above, and can be modified, improved, etc. as appropriate. Furthermore, the material, shape, dimensions, number, placement, etc. of each component in the embodiments described above are arbitrary and not limited as long as they can achieve the present invention.
[0028] In the above embodiment, the tape 3 is wrapped only around the cylindrical portion 20 of the grommet 1. In contrast, as shown in Figure 6, the tape 3 may be wrapped around both the cylindrical portion 20 and the wire bundle 2 inserted into the cylindrical portion 20. Specifically, the tape 3 is wrapped together around the cylindrical portion 20 and the wire bundle 2 so that the tip (upper end) of the cylindrical portion 20 and the wire bundle 2 located near the upper end of the cylindrical portion 20 are covered by the tape 3. By wrapping the tape 3 in this way, the gap between the open end (upper end) of the cylindrical portion 20 and the wire bundle 2 is sealed by the tape 3. This further improves the sealing performance of the cylindrical portion 20 and appropriately suppresses the displacement of the wire bundle 2 in the direction of the cylindrical axis of the cylindrical portion 20.
[0029] Herein, the features of the embodiment of the wire harness 4 according to the present invention described above are briefly summarized below.
[0030] [1] A wire harness (4) comprising an electric wire (2), a grommet (1) attached to the electric wire (2), and a fastener (3) attached to the grommet (1), The grommet (1) is It has a cylindrical portion (20) that is elastically deformable in the radial direction and through which the electric wire (2) is inserted, and a main body portion (10) that extends from the cylindrical portion (20) and is fitted into a through hole (Pa) of the mounting object (P), The cylindrical portion (20) is The cylindrical portion (20) has a first variable portion (21) which is configured such that a part of the cylindrical wall of the cylindrical portion (20) is recessed in a groove shape toward the radially outward direction and extends along the cylindrical axis of the cylindrical portion (20), The main body (10) is The first variable portion (21) has a second variable portion (14) which extends continuously from it and is configured such that a part of the main body portion (10) is recessed in a groove shape, The aforementioned fixing device (3) is The first variable part (21) is deformed to conform to the outer circumferential surface of the cylindrical part (20) and attached to the cylindrical part (20). Wire harness (4).
[0031] In the wire harness configuration described in [1] above, the cylindrical portion of the grommet is provided with a first variable portion configured such that a part of the cylindrical portion is grooved outward in the radial direction and extends along the cylindrical axis of the cylindrical portion, and the main body of the grommet is provided with a second variable portion configured to extend continuously with the first variable portion and be grooved. As a result, when the first variable portion is deformed so as to separate a pair of groove walls of the first variable portion that face each other in the circumferential direction of the cylindrical portion, the diameter of the cylindrical portion expands, and when the first variable portion is deformed so as to bring the pair of groove walls closer together, the diameter of the cylindrical portion contracts. The second variable portion deforms in conjunction with the deformation of the first variable portion, as its pair of groove walls move in conjunction with the deformation of the first variable portion. Due to the operation of the first and second variable portions in this way, the cylindrical portion can be easily expanded and contracted by the operator by hand without the use of a dedicated device (expander). As a result, the work of attaching the grommet to the electric wire can be made easier, and the possibility of damage to the cylindrical portion due to excessive expansion can be reduced. Furthermore, after passing the electric wire through the cylindrical section, the first variable section is deformed using a fixing device (e.g., tape) to conform to the outer surface of the cylindrical section, and the fixing device is then attached to the cylindrical section. This ensures that the cylindrical section maintains a tight seal with the electric wire. Therefore, this wire harness configuration offers excellent productivity.
[0032] [2] In the wire harness (4) described in [1] above, The first variable part (21) is, In a cross-section perpendicular to the cylindrical axis of the cylindrical portion (20), the thickness of the first variable portion (21) is smaller than the thickness of a portion other than the first variable portion (21), thus having a thin-walled structure. Wire harness (4).
[0033] According to the wire harness configuration described in [2] above, the first variable portion of the grommet has a thin-walled structure in which the thickness of the first variable portion is smaller than the thickness of a different portion. This makes it even easier to deform the first variable portion when inserting an electric wire into the cylindrical portion.
[0034] [3] In the wire harness (4) described in [1] above, The aforementioned fixing device (3) is The tape (3) is capable of being attached to the grommet (1), The aforementioned tape (3) is The grommet (1) is wrapped only around the cylindrical portion (20), or it is wrapped around both the cylindrical portion (20) and the electric wire (2) inserted into the cylindrical portion (20). Wire harness (4).
[0035] With the wire harness configuration described in [3] above, if the tape is wrapped only around the cylindrical portion of the grommet, the state in which the cylindrical portion is in close contact with the electric wire can be properly maintained as described above. Furthermore, by wrapping the tape around both the cylindrical portion and the electric wire inserted into the cylindrical portion, in addition to properly maintaining the state in which the cylindrical portion is in close contact with the electric wire, displacement of the electric wire in the direction of the cylindrical axis of the cylindrical portion can be properly suppressed. [Explanation of Symbols]
[0036] 1 grommet 2 Wire bundle (wire) 3. Tape (fastener) 4 Wire harness 10 Main body 14. Second variable section 20 Cylindrical part 21 First variable section P Body panel (for installation) Pa through hole
Claims
1. A wire harness comprising an electric wire, a grommet attached to the electric wire, and a fastener attached to the grommet, The grommet is, It has a cylindrical portion that is elastically deformable in the radial direction and through which the electric wire is inserted, and a main body portion that extends from the cylindrical portion and is fitted into a through hole in the object to be attached, The aforementioned cylindrical portion is The cylindrical portion has a first variable portion which is configured such that a part of the cylindrical wall of the cylindrical portion is recessed in a groove-like shape toward the radially outward direction and extends along the cylindrical axis of the cylindrical portion, The main body is, It has a second variable portion that extends continuously with the first variable portion and is configured such that a part of the main body portion is recessed in a groove shape, The aforementioned fixing device is The first variable part is deformed to conform to the outer circumferential surface of the cylindrical part, and is attached to the cylindrical part. Wire harness.
2. In the wire harness according to claim 1, The first variable part is, In a cross-section perpendicular to the cylindrical axis of the cylindrical portion, the thickness of the first variable portion is smaller than the thickness of a portion other than the first variable portion, thus having a thin-walled structure. Wire harness.
3. In the wire harness according to claim 1, The aforementioned fixing device is The tape is capable of adhering to the grommet, The aforementioned tape is The grommet is wrapped around only the cylindrical portion, or it is wrapped around both the cylindrical portion and the electric wire inserted into the cylindrical portion. Wire harness.