Grommet assembly and wire harness

A grommet assembly includes a grommet attached to a through hole formed on a panel, an inner member supported by the grommet, and a protector that is attached to the panel while covering the grommet and the inner member. The grommet includes a supporting part that supports the inner member. The supporting part includes a first extending part that extends from an outer side toward an inner side in a radial direction to be held between the inner member and the protector, and a second extending part that extends in an axial direction while being bent from the first extending part to be held between the inner member and the protector.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2022-096270 filed in Japan on Jun. 15, 2022.

BACKGROUND OF THE INVENTION

1. Field of the Invention

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

2. Description of the Related Art

In the related art, there are known a grommet assembly and a wire harness obtained by arranging a grommet in a through hole through which the wire harness is inserted as disclosed in Japanese Patent Application Laid-open No. 2020-74671, for example. In these grommet assembly and wire harness, a bracket is attached to a panel, and the grommet is supported by the bracket.

As the grommet assembly and the wire harness, it can be considered that an inner member is mounted on the grommet, and the grommet and the inner member are pressed against the panel by a protector. However, there is concern that a water cutoff function of the grommet is lowered. For example, when a wiring material of the wire harness is strongly pulled, it is assumed that the grommet is deformed, an end part of the grommet is turned up, and the water cutoff function of the grommet is lowered.

SUMMARY OF THE INVENTION

Thus, the present invention aims at providing a grommet assembly and a wire harness that can prevent the grommet from being deformed and secure the water cutoff function.

In order to achieve the above mentioned object, a grommet assembly according to one aspect of the present invention includes a grommet through which a wiring material is inserted, that is attached to a through hole formed on a panel for a vehicle; an inner member that is arranged on an opposite side of the panel for the vehicle with respect to the grommet, and supported by the grommet; and a protector through which the wiring material is inserted, that is attached to the panel for the vehicle while covering the grommet and the inner member, wherein the grommet includes a supporting part that supports the inner member, and the supporting part includes a first extending part that extends from an outer side toward an inner side in a radial direction to be held between the inner member and the protector, and a second extending part that extends in an axial direction while being bent from the first extending part to be held between the inner member and the protector.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following describes an embodiment according to the present invention in detail based on the drawings. The present invention is not limited to this embodiment. Constituent elements in the following embodiment encompass a constituent element that can be easily replaced by those skilled in the art, or substantially the same constituent element.

Embodiment

FIG.1is an exploded perspective view of a grommet assembly according to an embodiment, andFIG.2is a vertical cross-sectional view of the grommet assembly and a wire harness.FIG.3is an enlarged cross-sectional view of a grommet, andFIG.4is a perspective view of the grommet and an inner member.FIG.5is an explanatory diagram of a water cutoff function of the grommet.

As illustrated inFIGS.1and2, a grommet assembly1is an assembly for attaching a grommet2to a panel10, and includes the grommet2, an inner member3, and a protector4. A wire harness WH includes the grommet assembly1and a wiring material W. For example, the wire harness WH is configured by incorporating the grommet assembly1with the wiring material W routed in a vehicle. Herein, the wire harness WH is obtained by bundling a plurality of the wiring materials W to be a collective component, for example, and electrically connects between devices mounted on the vehicle. The wire harness WH may also include another component such as a corrugated tube and resin tape. The wiring material W has electrical conductivity, connects between devices mounted on the vehicle, and is used for power supply and signal communication. The wiring material W is, for example, constituted of a metal rod, an electric wire, an electric wire bundle, and the like. The metal rod is obtained by covering an outer side of a rod-like member having electrical conductivity with a covering part having an insulation property. The electric wire is obtained by covering an outer side of a conductor part (core wire) constituted of a plurality of metal wires having electrical conductivity with a covering part having an insulation property. The electric wire bundle is obtained by bundling the electric wires.

The panel10is a panel for the vehicle, and is a floor panel disposed on a floor portion of a vehicle body, for example. The panel10is an attachment target to which the grommet2is attached, and constituted of a plate-like member disposed in a horizontal direction. For convenience of explanation, part of the panel10is illustrated in a circular shape inFIG.1. An overall shape of the panel10is a shape corresponding to a structure of the vehicle, for example.

A through hole11is formed on the panel10. The through hole11is a hole through which the wire harness WH is inserted, and passes through front and back faces of the panel10to cause a vehicle exterior side of the panel10to communicate with a vehicle interior side thereof. InFIG.1, a lower side of the panel10is the vehicle exterior side, and an upper side thereof is the vehicle interior side.FIG.1illustrates a case in which the through hole11is opened in a circular shape, but there is a case in which the through hole11is opened in a shape other than the circular shape. Bolts12are disposed on a lower surface of the panel10. The bolts12are projected from the lower surface of the panel10toward a lower side. For example, the two bolts12are disposed at positions across the through hole11, for example. The bolt12functions as a fastening member for attaching the protector4to the panel10.

The grommet2is a member that is attached to the through hole11, and covers and protects the wiring material W inserted therethrough. The grommet2is, for example, constituted of an elastic body that can be elastically deformed, and constituted of rubber, an elastic resin material, or the like. The grommet2fills up a gap between the wiring material W and an inner edge of the through hole11to protect the wiring material W, and cuts off water inside and outside the vehicle. The grommet2may also function as a member that achieves dustproofing and soundproofing for the vehicle.

The grommet2includes a main body part21, an insertion part22, and a cylindrical part23. The main body part21is a part arranged on the vehicle exterior side of the panel10, and is formed to be larger than the through hole11to have a disc shape, for example. The insertion part22is a part to be inserted through the through hole11, and is formed to have a size that can be inserted through the through hole11and have a round pillar shape or a cylindrical shape, for example. The cylindrical part23is a part that covers the wiring material W inserted therethrough, and is projected from the main body part21or the insertion part22along a passing-through direction of the through hole11.FIG.1illustrates a case in which two cylindrical parts23are formed. One or three or more cylindrical parts23may be formed in accordance with the number of wiring materials W to be inserted.

A lip part24, a hollow part25, and a supporting part26are formed on the grommet2. The lip part24is a part abutting on the panel10, and is projected from the main body part21toward the panel10. The lip part24is formed as continuous projections surrounding a periphery of the insertion part22, for example. When the lip part24is pressure-welded to the panel10, the vehicle interior side and the vehicle exterior side of the through hole11are sealed off by the grommet2, and a water cutoff function of the grommet2is exhibited. In other words, in a case in which pressure-welding of the lip part24is not appropriately performed due to deformation of the grommet2, the water cutoff function of the grommet2is lowered.

As illustrated inFIG.3, the hollow part25is a hollow space portion in the grommet2, and formed in a region on the inner member3side with respect to the lip part24. That is, the hollow part25is formed in a region on the opposite side of the panel10with respect to the lip part24, and allows the lip part24pressure-welded to the panel10to be easily bent. For example, the hollow part25is formed as a groove extending in a circumferential direction by recessing an outer peripheral portion of the main body part21in a radial direction. The lip part24is pressed against the panel10when the grommet2is attached to the panel10. However, by forming the hollow part25, the lip part24can be bent to move toward the hollow part25side before being deformed to be crushed. In the grommet assembly1and the wire harness WH according to the present embodiment, the hollow part25is not formed in some cases.

The supporting part26is a part that supports the inner member3, and is formed on the inner member3side of the main body part21. That is, the supporting part26is formed at a position on the main body part21opposite to the panel10. The supporting part26is engaged with the inner member3, and enables the grommet2to be mounted on the inner member3. For example, the supporting part26supports the inner member3by covering an outer edge of a flange part32, and integrates the grommet2with the inner member3. Details of the flange part32will be described later.

Specifically, the supporting part26includes an outer cylindrical part26a, a first extending part26b, and a second extending part26c. The outer cylindrical part26ais formed in a cylindrical shape, and covers an outer peripheral portion of the flange part32. The first extending part26bis formed to be continuous to the outer cylindrical part26a, and extends from an outer side toward an inner side in a radial direction to cover a lower surface of the flange part32. The lower surface of the flange part32is a surface of the flange part32on the opposite side of the panel10. That is, the first extending part26bis formed along the surface of the flange part32on the opposite side of the panel10. The second extending part26cis formed to be continuous to the first extending part26b, and bent from the first extending part26bto extend in an axial direction.

The first extending part26band the second extending part26care disposed to be held between the inner member3and the protector4. That is, the first extending part26bis held between the flange part32of the inner member3and a first parallel surface41cof the protector4. The second extending part26cis held between a main body part31of the inner member3and a second inner peripheral surface41dof the protector4. Details of the first parallel surface41cand the second inner peripheral surface41dwill be described later. In this way, the first extending part26band the second extending part26care disposed to be held between the inner member3and the protector4in a bent state, so that the first extending part26band the second extending part26chardly come off from between the inner member3and the protector4.

InFIG.1, the inner member3is a member that is attached to the grommet2. The inner member3is, for example, constituted of a resin member, and has higher rigidity than that of the grommet2. The inner member3is arranged to abut on a side of the grommet2opposite to the panel10. Due to this, in a case in which the protector4is attached to the panel10, pressing force from the protector4can be received by the inner member3to be transmitted to the grommet2. The inner member3may be arranged so that at least part thereof abuts on the side of the grommet2opposite to the panel10, and the other part is not necessarily arranged on the side of the grommet2opposite to the panel10.

The inner member3includes the main body part31, the flange part32, and locking parts33. The main body part31is formed in a cylindrical shape, and is arranged so that an axial direction agrees with the passing-through direction of the through hole11. The axial direction is a direction along a center axis of the main body part31, which is the Z-direction illustrated in the drawing. The wiring material W can be inserted through the main body part31. The flange part32is formed to extend outward in the radial direction from the main body part31to be parallel with the panel10. The radial direction is a radial direction of the main body part31, which is a direction orthogonal to the axial direction. For example, as illustrated inFIG.3, the flange part32extends outward in the radial direction from a position on the panel10side of the main body part31, and extends to the position of the lip part24of the grommet2. Due to this, when the protector4is attached to the panel10, the lip part24can be pressed by the flange part32of the inner member3having high rigidity, and the grommet2can be securely pressed against the panel10.

InFIG.1, the main body part31and the flange part32are disposed in an annular shape, but they may have a structure combining two semi-annular members, for example. In this case, the main body part31and the flange part32can be divided into two semi-annular members, or can be opened and closed. That is, insertion of the wiring material W is facilitated such that the wiring material W is inserted in a state in which they are opened or divided into two semi-annular members, and they are combined to be the main body part31and the flange part32having an annular shape thereafter.

As illustrated inFIG.4, the locking part33is a part that is disposed on an outer circumference of the main body part31for locking the protector4. For example, a plurality of the locking parts33are disposed. InFIG.4, three locking parts33are disposed at intervals along a circumferential direction of the inner member3. Two or four or more locking parts33may be disposed. The locking part33includes an arm33aand a locking pawl33b. The arm33aprojects outward in the radial direction from an outer peripheral surface of the main body part31. The locking pawl33bis formed to extend in the axial direction from a distal end of the arm33a. That is, the locking pawl33bis bent from the arm33ato extend toward the protector4side in the axial direction, and can be locked onto the protector4. At a distal end portion of the locking pawl33b, a hook part33cprojecting in the radial direction is formed. In the grommet assembly1and the wire harness WH according to the present embodiment, the inner member3may be locked on the protector4using a member other than the locking part33.

The locking part33of the inner member3is disposed to be adjacent to the first extending part26band the second extending part26c. That is, the first extending part26band the second extending part26care arranged to be adjacent to an end face in a circumferential direction of the locking part33, and regulates relative rotational movement of the grommet2and the inner member3. Specifically, a recessed part27is formed on the first extending part26band the second extending part26c, and the locking part33is inserted into the recessed part27. The recessed part27is formed by recessing the first extending part26band the second extending part26coutward in the radial direction so that the locking part33can be inserted therein. A plurality of the recessed parts27are disposed in accordance with forming positions and the number of formed locking parts33in the circumferential direction. That is, the locking part33and the recessed part27are disposed so that the locking part33is inserted into the recessed part27in a case in which the inner member3is mounted on the grommet2.

As illustrated inFIGS.1and2, the protector4is a member that protects the grommet2, the inner member3, and the wiring material W, and regulates a routing path of the wiring material W. The protector4is attached to the panel10so as to house the grommet2, the inner member3, and the wiring material W, and holds the grommet2and the inner member3between the protector4and the panel10.

The protector4includes a base member40that covers the grommet2, the inner member3, and the wiring material W. The base member40includes a first base part41and a second base part42. The first base part41is a part that is arranged at a forming position of the through hole11to cover and protect the grommet2and the inner member3. The first base part41is formed in a cylindrical shape in which an end face on the panel10side is opened. In a case in which the protector4is attached to the panel10, the first base part41covers the grommet2and the inner member3, and protects the grommet2and the inner member3.

The second base part42is formed to be continuous to the first base part41, and is disposed to project in the radial direction from a side part of the first base part41. The wiring material W extending from the first base part41is inserted through the second base part42. That is, the wiring material W is inserted through the first base part41while being bent from the axial direction to the radial direction, and extends from the first base part41to be inserted through the second base part42. In a case in which the protector4is attached to the panel10, the second base part42protects the wiring material W inserted therethrough.FIG.1illustrates the protector4in a state in which a cover42athat covers a side surface portion of the first base part41and the panel10side of the second base part42is removed.

InFIGS.2and3, an internal space41aof the first base part41has a round pillar shape, for example, and is a stepped space the inner diameter of which is reduced as being separated from the panel10. That is, the internal space41ais defined by a first inner peripheral surface41b, a first parallel surface41c, a second inner peripheral surface41d, a second parallel surface41e, a third inner peripheral surface41f, and a bottom surface41g. That is, in the internal space41a, inner peripheral surfaces are formed in order of the first inner peripheral surface41b, the second inner peripheral surface41d, and the third inner peripheral surface41ffrom the panel10side. An inner diameter of the second inner peripheral surface41dis smaller than an inner diameter of the first inner peripheral surface41b, and an inner diameter of the third inner peripheral surface41fis smaller than an inner diameter of the second inner peripheral surface41d. The first parallel surface41cformed to be parallel with the panel10is formed between the first inner peripheral surface41band the second inner peripheral surface41d, and the second parallel surface41eformed to be parallel with the panel10is formed between the second inner peripheral surface41dand the third inner peripheral surface41f. Due to this, the internal space41ahas a shape having two steps.

In the internal space41a, the grommet2and the flange part32of the inner member3are arranged on an inner side of the first inner peripheral surface41b. The supporting part26of the grommet2covering the flange part32abuts on the first parallel surface41c. The main body part31of the inner member3abuts on the second parallel surface41e. Due to this, when the protector4is attached to the panel10, the grommet2can be pressure-welded to the panel10via the inner member3.

InFIG.1, an insertion hole43through which the bolt12is inserted is bored on the protector4. The insertion hole43is a hole that is formed in the axial direction, and is formed at a projecting part44projected in the radial direction from the outer peripheral surface of the first base part41, for example. The insertion hole43and the projecting part44are formed corresponding to arrangement positions of the bolts12. InFIG.1, two insertion holes43and two projecting parts44are formed corresponding to the two bolts12.

Next, the following describes an assembly method for the grommet assembly and the wire harness according to the present embodiment.

First, as illustrated inFIG.1, the wiring material W is inserted through the grommet2. For example, the wiring material W is inserted through the grommet2as an elastic body while a diameter of the grommet2is expanded. The inner member3is then assembled to the wiring material W. For example, the main body part31and the flange part32of the inner member3are divided or opened, and the wiring material W is arranged on an inner side of the inner member3. When the main body part31and the flange part32are assembled to each other or closed to have an annular shape, the inner member3is assembled to the wiring material W. The wiring material W is then inserted through the protector4. For example, the cover42aof the protector4is opened, and the wiring material W is inserted through inner parts of the first base part41and the second base part42of the protector4. The cover42ais then closed, and the protector4is assembled to the wiring material W.

Thereafter, as illustrated inFIGS.3and4, the grommet2is mounted on the inner member3. That is, the flange part32of the inner member3is covered by the supporting part26of the grommet2, and the grommet2is mounted on the inner member3. At this point, the inner member3and the grommet2are joined so that the locking part33of the inner member3is inserted into the recessed part27of the grommet2. The supporting part26covers the flange part32from a side surface to a lower surface, so that the flange part32can be securely supported. When the locking part33is inserted into the recessed part27, relative rotational movement of the grommet2and the inner member3is suppressed.

Next, the grommet2and the inner member3are attached to the protector4. As illustrated inFIG.2, the grommet2and the inner member3are housed in the internal space41aof the first base part41. At this point, the grommet2and the inner member3are housed in the internal space41aso that the locking pawl33bof the inner member3is inserted into a hole part45of the protector4. When the locking pawl33bis hooked on a part to be locked of the protector4, the inner member3is locked to the protector4, and the grommet2, the inner member3, and the protector4are integrated with each other.

The protector4is then attached to the panel10. As illustrated inFIG.2, the first base part41of the protector4is aligned with the position of the through hole11, and the lip part24of the grommet2abuts on the panel10. As illustrated inFIG.1, when the bolt12is inserted through the insertion hole43of the protector4, the protector4is arranged at a correct position with respect to the panel10. The grommet2and the inner member3are arranged at correct positions with respect to the protector4, so that arrangement positions of the grommet2and the inner member3with respect to the panel10become correct positions. Due to this, the grommet2is attached while being appropriately arranged with respect to the through hole11without using a metal plate.

A nut (not illustrated) is screwed onto the bolt12to be fastened. Due to this, the protector4is brought close to the panel10to be fixed. At this point, as illustrated inFIG.3, the protector4presses the grommet2via the inner member3, and the lip part24of the grommet2is pressure-welded to the panel10. Due to this, for example, as compared with a case in which a portion as the inner member3is an elastic body and configured as part of the grommet2, excessive deformation of the grommet2can be suppressed, and a water cutoff function of the grommet2can be appropriately exhibited. That is, if the portion as the inner member3is constituted of a member having the same rigidity as that of the grommet2, the protector4presses the entire grommet2. In this case, stress is applied to the entire grommet2, and portions other than the lip part24are unnecessarily deformed. Due to this, there is the possibility that the grommet2cannot exhibit a desired water cutoff function. In contrast, the grommet2according to the present embodiment can suppress such a failure, and can exhibit an appropriate water cutoff function.

When the protector4is attached to the panel10, attachment of the grommet2, the inner member3, and the wire harness WH is completed, and the wiring material W can be inserted through the through hole11of the panel10to be arranged.

Next, the following describes the water cutoff function of the grommet assembly and the wire harness according to the present embodiment.

As illustrated inFIG.2, the grommet2is attached to the through hole11, and the lip part24of the grommet2is pressed against the panel10. Due to this, the vehicle interior side and the vehicle exterior side of the panel10are sealed off by the grommet2, and water is prevented from entering the vehicle from the vehicle exterior side to the vehicle interior side via the through hole11.

Herein, as illustrated inFIG.5, there is a case in which the wiring material W is pulled. For example, at the time of attachment of the wire harness WH, the wiring material W may be pulled toward a lateral side. At this point, the cylindrical part23is also pulled together with the wiring material W, and tensile force T applied to the cylindrical part23is transmitted to the supporting part26via the main body part21and the insertion part22.

As illustrated inFIG.3, the supporting part26includes the first extending part26band the second extending part26c, and the first extending part26band the second extending part26care sandwiched and held between the inner member3and the protector4. That is, the first extending part26bis sandwiched and held between the flange part32and the first parallel surface41c, and the second extending part26cis sandwiched and held between an outer peripheral surface of the main body part31and the second inner peripheral surface41d. The first extending part26band the second extending part26care sandwiched and held between the inner member3and the protector4in a bent state. Due to this, the first extending part26band the second extending part26care not easily pulled out from between the inner member3and the protector4even when the tensile force T is applied to the supporting part26. Thus, with the grommet assembly1and the wire harness WH, the supporting part26at the end part of the grommet2is prevented from being turned up, and the lip part24is prevented from being separated from the panel10. Accordingly, a desired water cutoff function of the grommet2can be secured.

The supporting part26covers the outer edge of the flange part32to support the inner member3, and extends around the outer edge of the flange part32to form the first extending part26balong a surface on the opposite side of the panel10. Due to this, the grommet assembly1and the wire harness WH have a structure in which the first extending part26bis hardly pulled out from the panel10side. Thus, the grommet assembly1and the wire harness WH can prevent the end part of the grommet2from being turned up and exhibit a high water cutoff function even when the wiring material W is pulled.

Furthermore, the inner member3is arranged to abut on the side of the grommet2opposite to the panel10, and the protector4is attached to the panel10so as to hold the grommet2and the inner member3between the protector4and the panel10. Due to this, with the grommet assembly1and the wire harness WH, the first extending part26bcan be strongly held between the protector4and the inner member3when the protector4is attached to the panel10. Thus, the grommet assembly1and the wire harness WH can have a structure in which the first extending part26bhardly comes off from between the protector4and the inner member3, and the water cutoff function of the grommet2can be reliably secured.

As described above, in the grommet assembly1and the wire harness WH according to the present embodiment, the supporting part26of the grommet2includes the first extending part26bthat extends from the outer side toward the inner side in the radial direction to be held between the inner member3and the protector4, and the second extending part26cthat is continuous to the first extending part26bwhile being bent and extends in the axial direction to be held between the inner member3and the protector4. That is, the first extending part26band the second extending part26cof the supporting part26are held between the inner member3and the protector4in a bent state. Due to this, even in a case in which the tensile force T is applied to the grommet2as the wiring material W is pulled, for example, the first extending part26band the second extending part26care prevented from coming off from between the inner member3and the protector4. Thus, with the grommet assembly1and the wire harness WH, the end part of the grommet2is hardly turned up, and a desired water cutoff function of the grommet2can be secured.

In the grommet assembly1and the wire harness WH according to the present embodiment, the supporting part26covers the outer edge of the flange part32to support the inner member3, and extends around the outer edge of the flange part32to form the first extending part26balong the surface on the opposite side of the panel10. Due to this, the grommet assembly1and the wire harness WH have a structure in which the first extending part26bis hardly pulled out from the panel10side. Thus, with the grommet assembly1and the wire harness WH, the end part of the grommet2is more hardly turned up, and a desired water cutoff function of the grommet2can be secured.

Furthermore, in the grommet assembly1and the wire harness WH according to the present embodiment, the first extending part26band the second extending part26care arranged to be adjacent to the end face in the circumferential direction of the locking part33. Due to this, with the grommet assembly1and the wire harness WH, relative rotational movement of the grommet2and the inner member3can be regulated by the supporting part26and the locking part33.

The embodiment of the present invention is exemplified above. However, the embodiment described above is merely an example, and does not intend to limit the scope of the invention. The embodiment described above can be implemented in various other forms, and can be variously omitted, replaced, combined, and modified without departing from the gist of the invention. Additionally, specs such as each configuration and a shape (a structure, a type, a direction, a format, a size, a length, a width, a thickness, a height, the number, arrangement, a position, a material, and the like) can be appropriately changed.

For example, in the above embodiment, described is a case of attaching the grommet assembly1and the wire harness WH to the panel10as the floor panel of the vehicle, but the embodiment can also be applied to a case of attaching the grommet assembly1and the wire harness WH to a panel for a vehicle other than the floor panel or another panel.

With the grommet assembly and the wire harness according to the present embodiment, the grommet can be prevented from being deformed and the water cutoff function can be secured.