JP2008137509A - Wiper shaft water-proof structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To certainly perform water-proof regardless of a curvature of a curved part of a wiper shaft insertion port edge side part. <P>SOLUTION: A grommet 20 mounted between the wiper shaft 12 and the insertion port 2 is provided with a covering part 21 for covering the wiper shaft 12; and a fixed part 25 connected to the covering part 21 at a folded/returned part 24 and fixed to the insertion port 2. A fitting groove 27 fitted to the insertion port edge side part 3 is annularly formed on an outer periphery of the body 26 of the fixed part 25 formed to a cylindrical shape, and a lip 28 is formed at the covering part 21 side of the fitting groove 27 of the outer periphery of the body 26. An extension part 29 followable to the curvature of the curved part 4 of the insertion port edge side part 3 is formed on the lip 28 by an opening angle θ in a circumferential direction corresponding to the curved part 4. Even when the curvature of the curved part of the insertion port edge side part is large, since the extension part is sufficiently elastically deformed and closely adhered to an outer surface of the curved part, formation of a clearance is prevented and water-proof can be certainly performed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wiper shaft waterproofing structure, for example, to an effective one for sealing a wiper shaft of a wiper device mounted on an automobile.

2. Description of the Related Art Generally, in a rear wiper device for an automobile, a wiper shaft is inserted through a wiper shaft insertion opening (hereinafter referred to as an insertion opening) provided in a rear panel or rear windshield glass of a vehicle body.
As described above, since the wiper shaft is inserted through the insertion port, the wiper shaft and the insertion port need to be waterproofed.

  In this type of conventional wiper shaft waterproof structure, a cylindrical portion formed at one end of a rubber grommet is fitted to the outer periphery of the wiper shaft, and an outer flange portion formed at the other end of the grommet. And the inner flange portion sandwich the edge of the insertion opening. For example, see Patent Document 1.

JP 2003-118543 A

  However, in the wiper shaft waterproof structure described above, the curvature [curvature] of the curved portion (arc portion) formed at the edge portion of the wiper shaft insertion opening of the rear panel. If the reciprocal of the radius of curvature is large, the outer peripheral lip of the outer flange part cannot follow the rear panel surface and a gap is formed, causing water to enter the rear panel. was there.

  An object of the present invention is to provide a wiper shaft waterproof structure that can reliably waterproof regardless of the curvature of a curved portion formed at the edge of the wiper shaft insertion opening.

Typical means for solving the above-described problems are as follows.
(1) In a wiper shaft waterproof structure in which a wiper shaft is attached to pass through a wiper shaft insertion port provided in a vehicle body, and a grommet for connecting the wiper shaft and the wiper shaft insertion port is attached.
The grommet includes a covering portion that partially covers the wiper shaft in the longitudinal direction, and a fixing portion that is connected to the covering portion and fixed to the wiper shaft insertion port,
The fixed portion includes a main body formed in a cylindrical shape, a fitting groove formed in an annular shape on the outer periphery of the main body and fitted to an edge portion of the wiper shaft insertion opening, and the fitting groove on the outer periphery of the main body. A lip formed on the covering portion side of
The wiper shaft waterproof structure according to claim 1, wherein an extended portion of the lip is partially formed integrally with the lip.
(2) The extending range in the circumferential direction of the extending part is set so as to correspond to an opening angle at the center of the wiper shaft insertion port corresponding to the circumferential range of the bent part. The wiper shaft waterproof structure according to (1).
(3) The wiper shaft waterproof structure according to (1) or (2), wherein a mark that indicates a position of the extension portion is displayed on the grommet.
(4) The wiper shaft waterproof structure according to (1), (2), or (3), wherein an assembly guide is formed on an outer peripheral edge of the main body opposite to the covering portion. .
(5) The wiper shaft waterproofing structure according to (1), (2), (3) or (4), wherein the extending portion overhangs the assembly guide.

  According to said (1), since the extension part integrally formed in the lip | rip of the grommet can be elastically deformed according to the curvature of the curved part formed in the wiper shaft insertion port edge part, a wiper shaft Even when the curvature of the bent portion formed at the edge of the insertion opening is large, it is possible to prevent a gap from being formed by sufficiently following and sticking, and to be reliably waterproofed.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In the present embodiment, the wiper shaft waterproof structure according to the present invention is applied to a rear wiper device of an automobile.
That is, as shown in FIG. 1, a wiper shaft insertion port (hereinafter referred to as an insertion port) 2 is provided in the rear panel 1 in the vicinity of the rear windshield glass of the automobile. A wiper shaft 12 of a wiper motor (only part of which is shown) is inserted. The insertion port 2 may be opened in the rear windshield glass.
A base end portion 14 of a wiper arm (only part of which is shown) 13 is fitted to the protruding end portion of the wiper shaft 12 and fastened by a nut 15. An insertion hole 16 is recessed in the end surface of the base end portion 14 of the wiper arm 13 opposite to the nut 15.

  As shown in FIG. 1, a grommet 20 is fitted between the wiper shaft 12 and the insertion opening 2. The grommet 20 is integrally formed into a substantially double cylindrical shape using a rubber or resin elastic material having an appropriate elastic force.

As shown in FIG. 2, the grommet 20 includes a covering portion 21 that partially covers the wiper shaft 12 in the longitudinal direction. The inner diameter of the covering portion 21 is set larger than the outer diameter of the wiper shaft 12, and the outer diameter is set smaller than the inner diameter of the insertion port 2.
A plurality of inner annular lips 22 having a triangular cross section are juxtaposed in parallel in the axial direction on the inner peripheral surface of one end of the covering portion 21, and the inner annular lip 22 has a tip at the outer periphery of the wiper shaft 12. It is configured to be in sliding contact with the surface. That is, the front end surface of the inner annular lip 22 and the outer peripheral surface of the wiper shaft 12 are relatively rubbed with each other as the wiper shaft 12 rotates. The seal between the 12 outer peripheral surfaces is maintained.
On the outer periphery of the end portion of the covering portion 21 where the inner annular lip 22 is formed, a conical cylinder-shaped outer annular lip 23 projects in a concentric manner. As shown in FIG. 1, in a state where the grommet 20 is inserted into the insertion hole 16 of the wiper arm 13, the outer annular lip 23 is in sliding contact with the inner peripheral surface of the insertion hole 16 of the wiper arm 13. It is possible to maintain a sealing property between the distal end surface of the insertion hole 16 and the inner peripheral surface of the insertion hole 16 by relatively rubbing with the rotation of the wiper shaft 12. it can.

  As shown in FIGS. 1 and 2, one end of the folded portion 24 is integrally connected to the end of the covering portion 21 opposite to the outer annular lip 23, and the other end of the folded portion 24 is connected to the other end of the folded portion 24. Is fixedly connected to a fixing portion 25 which is inserted into and fixed to the insertion port 2.

The fixing portion 25 includes a main body 26. The main body 26 is formed in a thick cylindrical shape in which the outer peripheral side is a truncated cone shape and the inner peripheral side is formed in a columnar shape.
A fitting groove 27 is formed in an annular groove shape on the outer periphery of the main body 26, and the fitting groove 27 is configured to be fitted to the edge portion 3 of the insertion port 2 in the rear panel 1.
A lip 28 is formed over the entire circumference of the conical surface of the main body 26 on the covering portion 21 side of the fitting groove 27 on the outer periphery of the main body 26, and the lip 28 is restored by elastic deformation of the grommet 20 itself. Thus, it is set so as to follow and adhere to the outer surface of the rear panel 1 at the edge 3 of the insertion opening 2.

An extension portion 29 is formed on a part of the lip 28 so as to extend partially from the lip 28 to the side opposite to the covering portion 21. As shown in FIG. 1, the circumferential position of the extending portion 29 corresponds to the bent portion 4 of the rear panel 1 formed on the edge portion 3 of the insertion opening 2. The extending portion 29 is set to follow the bent portion 4 of the rear panel 1 formed at the edge portion 3 of the insertion opening 2 by being elastically deformed by the elastic force of the grommet 20 itself.
As shown in FIG. 1, FIG. 2A, and FIG. 3, a mark 30 that indicates the position of the extended portion 29 is a convex portion at a position facing the extended portion 29 on the outer peripheral surface of the main body 26. It is formed and displayed in a shape.
As shown in FIG. 2B, the circumferential extension range in which the extension portion 29 is provided is set by the opening angle Θ at the center of the insertion port 2, and the opening angle Θ is determined by the rear panel. 1 is set so as to correspond to the circumferential range of the bent portion 4 formed in 1.

As shown in FIGS. 1 and 2, a mounting base 31 is formed on the opposite side of the fitting groove 27 of the main body 26, and an assembly guide having an R chamfered shape is formed on the outer peripheral edge of the mounting base 31. The part 31a is formed over the entire circumference. The extension part 29 is configured to overhang the assembly guide part 31a.
The fitting groove 27 has a constant depth from the outer peripheral end of the mounting base 31, and the width between the main body 26 and the mounting base is also constant.

  The assembling work, operation, and effect of the grommet 20 and the wiper shaft 12 according to the above configuration to the insertion port 2 will be described.

With the wiper arm 13 removed from the wiper shaft 12, the grommet 20 is fitted to the tip of the wiper shaft 12.
By this fitting, the inner annular lip 22 of the covering portion 21 is in sliding contact with the outer peripheral surface of the wiper shaft 12.

As shown in FIG. 1, when the wiper motor 11 is assembled to the rear panel 1, a mark 30 (see FIG. 3) indicating the position of the extending portion 29 is formed on the edge portion 3 of the insertion port 2. The end portion of the main body 26 opposite to the covering portion 21 is assembled so as to be aligned with the bent portion 4 and pushed into the insertion port 2 with the mounting base 31 as a guide. That is, the edge 3 of the insertion port 2 is inserted into the fitting groove 27 in a state where the grommet 20 is properly aligned with the insertion port 2.
At this time, since the assembly guide portion 31a is formed in an R chamfered shape, the end portion of the main body 26 opposite to the covering portion 21 is smoothly received in the insertion port 2 and the insertion groove 2 is inserted into the fitting groove 27. The edge part 3 fits smoothly.
Although a positioning part for positioning the mark 30 may be provided on the rear panel 1 side, it is not necessary to provide a positioning part on the rear panel 1 side by setting the position of the mark 30 up or down.

After the grommet 20 is assembled to the insertion opening 2, the extension portion 29 is elastically deformed by the elastic force of the grommet 20 itself, and thus follows the curvature of the bent portion 4 of the rear panel 1. Can be securely attached to each other.
That is, the extending portion 29 extending from the lip 28 has a large elastic deformation allowance (amount), so that it can be elastically deformed to follow the large curvature even when the curvature of the curved portion 4 is large. Therefore, it is possible to reliably adhere to the outer surface of the bent portion 4 of the rear panel 1.
In other words, the grommet 20 including the bent portion 4 having a large curvature is securely in contact with the outer surface of the rear panel 1 at the edge of the insertion port 2 over the entire circumference, thereby reliably preventing water from entering the insertion port 2. can do.

Thereafter, the base end portion 14 of the wiper arm 13 is fitted to the distal end portion of the wiper shaft 12 and fastened by the nut 15.
As the nut 15 is fastened, the tip of the covering portion 21 of the grommet 20 is inserted into the insertion hole 16, and the outer annular lip 23 is placed inside the recess of the insertion hole 16. In addition, it is possible to prevent water from entering the wiper motor 11 through the wiper shaft 12.

  Needless to say, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

  For example, the mark that indicates the position of the extension is not limited to the convex shape, and may be formed in a concave shape or may be omitted.

  The annular lip on the inner peripheral surface of the hollow portion of the covering portion is not limited to a plurality of protrusions, but may be one or may be omitted.

  Although the wiper shaft waterproof structure of the rear wiper device has been described in the above embodiment, the wiper shaft prevention structure according to the present invention can be applied to wiper shaft waterproof structures such as a front wiper device in general.

1 is an enlarged longitudinal sectional view showing a wiper shaft waterproofing structure according to an embodiment of the present invention. The grommet is shown, (a) is a longitudinal cross-sectional view, (b) is a bottom view. It is a perspective view which shows a grommet.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Rear panel (vehicle body), 2 ... Insertion port (wiper shaft insertion port), 3 ... Edge part, 4 ... Curved part, 11 ... Wiper motor, 12 ... Wiper shaft, 13 ... Wiper arm, 14 ... Base end part, 15 ... Nut , 16 ... Insertion hole, 20 ... Grommet, 21 ... Covering part, 22 ... Inner annular lip, 23 ... Outer annular lip, 24 ... Folded part, 25 ... Fixed part, 26 ... Main body, 27 ... Fitting groove, 28 ... Lip , 29 ... Extension part, 30 ... Mark, 31 ... Mounting base, 31a ... Assembly guide part.

Claims (5)

In the wiper shaft waterproof structure in which a wiper shaft is attached to pass through a wiper shaft insertion port provided in the vehicle body, and a grommet for connecting the wiper shaft and the wiper shaft insertion port is attached.
The grommet includes a covering portion that partially covers the wiper shaft in the longitudinal direction, and a fixing portion that is connected to the covering portion and fixed to the wiper shaft insertion port,
The fixed portion includes a main body formed in a cylindrical shape, a fitting groove formed in an annular shape on the outer periphery of the main body and fitted to an edge portion of the wiper shaft insertion opening, and the fitting groove on the outer periphery of the main body. A lip formed on the covering portion side of
The wiper shaft waterproof structure according to claim 1, wherein an extended portion of the lip is partially formed integrally with the lip.   The extension range in the circumferential direction of the extension part is set so as to correspond to an opening angle at the center of the wiper shaft insertion port corresponding to the circumferential range of the bent part. The wiper shaft waterproof structure according to 1.   The wiper shaft waterproofing structure according to claim 1 or 2, wherein a mark indicating the position of the extending portion is displayed on the grommet.   4. The wiper shaft waterproof structure according to claim 1, wherein an assembly guide is formed on an outer peripheral edge of the main body opposite to the covering portion.   The wiper shaft waterproof structure according to claim 1, 2, 3, or 4, wherein the extending portion overhangs the assembly guide.

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