JP2001328510A - Wiper arm - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiper arm reducing the cost by using a thin plate material, securing a desired rigidity, and having design of a superior external appearance. SOLUTION: An arm body 5 constituting the wiper arm and having a retainer part 5a and a piece part 5c integrally formed of the same plate material is provided with a fold part 16 to be folded so as to be stacked on a side plate 12 comprising the external shape in a prescribed range E4 including a part (intermediate part 5b), with the rigidity lower than the prescribed rigidity (optimal value Y) on its external shape. The provision of the fold part 16 increases the apparent plate thickness of the inner side plate 12 in the region E4 more than the thickness of plates except for the region E4 so as to enhance the rigidity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiper arm used for a wiper device for wiping raindrops or the like attached to the surface of a windshield (windshield) of an automobile.

[0002]

2. Description of the Related Art Conventionally, a wiper arm of this type has an arm head fixed to a pivot shaft rotated at a predetermined angle by a wiper motor, a retainer rotatably connected to the arm head, and a wiper arm. The arm piece was fixed by caulking and a wiper blade was connected to the tip, and an urging spring was mounted between the arm head and the retainer and urged the wiper arm toward the glass surface.

[0003] However, in the wiper arm having the above-described structure, a step occurs at a connecting portion between the retainer and the arm piece. Therefore, there is a problem that appearance is not good. Further, since the retainer and the arm piece are separate parts, there is also a problem that the number of parts is large and the number of assembling steps is increased.

[0004] A technique for solving the above problem is disclosed in Japanese Utility Model Laid-Open No. 4-34160. The wiper arm of this publication includes an arm head and an arm blade.

[0005] The arm blade has a side wall bent at both ends in the width direction of the ceiling wall from the center to the base end side (arm head side), and has a substantially U-shaped cross section to accommodate a tension spring in the opening. (Substantially C-shaped). Arm blade center to tip end side (wiper blade side)
Is formed in a plate shape integral with the top wall by folding the side wall toward the top wall side, and the plate-shaped tip is connected to the wiper blade. It is bent. Also, the top wall and the side wall of the section having the U-shaped cross section are formed so as to gradually become narrower so that the outer shapes are smoothly connected from the base end side to the plate-shaped portion on the front end side. I have.

That is, in such an arm blade, a portion corresponding to the above-described retainer and the arm piece is integrally formed by subjecting a single plate to press punching or bending. Therefore, the arm blade of this publication does not have the above-described step, so that the appearance is good and the number of parts can be reduced.
Assembly man-hours can also be reduced.

[0007]

The optimum value of the stiffness required in each part of the arm blade is to decrease substantially linearly at a predetermined inclination from the base end to the tip end of the blade. It is desirable because there is no waste for the required rigidity, and the arm blade is preferably designed to approximate its linearly changing optimum value. This is because the moment of force due to the tensile force of the tension spring provided on the base end side of the arm blade becomes maximum at the base end, and gradually decreases toward the tip end, so that the required rigidity also increases from the base end. This is because the smaller the tip, the smaller it is. Therefore, with such a design, an arm blade having optimum rigidity can be formed without using an extra material.

Conventionally, however, a plate material having such a thickness that the portion having the lowest rigidity in the shape of the arm blade obtains the required rigidity has been selected. Then, the arm blade, which emphasizes the appearance, needs to accommodate a tension spring in the opening at the base end thereof, so that the width of the top wall and the side wall at the base end is set to be large, and the rigidity is more than necessary. It will be done. Further, when the thickness of the arm blade is set as described above, an expensive thick plate material must be used, and the material cost increases. Further, it is difficult to press-punch a thick plate material, and a large press pressure is required at the time of processing, so that the press machine becomes large. By these,
The cost of the arm blade (wiper arm) increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to use a thin plate material to reduce the cost and secure a desired rigidity while providing a good-looking design. To provide a wiper arm.

[0010]

According to a first aspect of the present invention, there is provided an arm head fixed to a pivot shaft and rotatably connected to the arm head. A side plate is bent from both ends in the width direction, and each of the side plates is bent so that the side plate is bent so as to face the top plate, and a retainer portion having a substantially U-shaped cross section opened to the wiping surface side and opened to the wiping surface side. An arm body integrally formed by bending a plate material, and an arm head housed in the opening of the retainer section for urging a tip end of the arm body toward a wiping surface side. And a biasing means provided between the arm body and the arm body, wherein the arm body has, in its outer shape, a predetermined area including a portion lower than desired rigidity, Includes a folded portion which is folded so as to overlap the portion constituting the outer shape, and the thickness of the apparent plate in the area is increased than the thickness of other than the region to increase the stiffness.

According to a second aspect of the present invention, in the wiper arm according to the first aspect, the folded portion is provided at least from a portion where the arm body changes from a retainer portion to a piece portion.

[0012] The invention according to claim 3 is the invention according to claim 1 or 2.
In the wiper arm described in the above item, the folded portion has a
It turns back only once. (Operation) According to the first aspect of the present invention, the arm main body that constitutes the wiper arm and in which the retainer portion and the piece portion are integrally formed of the same plate material has a lower rigidity than a desired rigidity due to its outer shape. In a predetermined region including the portion, a folded portion is provided to be folded so as to overlap with a portion constituting the outer shape. By providing such a folded portion, the apparent plate thickness of the plate material in the region is increased from the plate thickness in the region other than the region, and the rigidity is increased. Therefore, the entire arm body is not formed by using an expensive thick plate, but can be formed by using an inexpensive thin plate by partially increasing the rigidity by the folded portion. In addition, since the stiffness of the arm body can be partially increased by the folded portion, the design of the arm body in which the retainer portion and the piece portion are integrally formed of the same plate material is not spoiled.

According to the second aspect of the present invention, the folded portion is provided at least from a portion where the arm body changes from the retainer portion to the piece portion. Here, in the case where the retainer portion and the piece portion are integrally formed of the same plate material to form the arm body, the portion where the cross-sectional shape changes from substantially U-shaped (retainer portion) to substantially plate-shaped (piece portion) has the highest rigidity. The decrease can be estimated from the section modulus, and the result of analysis by the inventors has been confirmed (see FIG. 3B). Therefore, by providing the folded portion in this portion, the rigidity of the arm main body can be most effectively increased, and the required strength can be secured.

According to the third aspect of the present invention, since the folded portion is folded only once, an increase in the number of bending processes of the arm main body can be suppressed as much as possible.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a vehicle wiper for wiping a windshield glass (front glass) of a vehicle. FIG. 2A is a plan view of the wiper arm, and FIG. 2B is a side view of the wiper arm.
FIG. 3A is a bottom view of the wiper arm, and FIG. 4 is an enlarged view of a main part of the bottom view of the wiper arm. FIG.
5A is a cross-sectional view of FIG. 4, and FIG.
4C is a cross-sectional view taken along the line CC of FIG. 4, and FIG.
It is D sectional drawing.

As shown in FIG. 1, the vehicle wiper 1 includes a wiper arm 2 and a wiper blade 3. The wiper arm 2 includes an arm head 4 fixed to a pivot shaft rotated at a predetermined angle by a wiper motor (not shown), an arm body 5 having a base end rotatably connected to the arm head 4, An urging spring 6 is mounted between the main body 5 and the arm head 4 to urge the wiper arm 2 toward the glass surface. On the other hand, the wiper blade 3 is connected to the wiper arm 2 (arm body 5).
And a blade rubber 8 held by the lever assembly 7 and in contact with the glass surface. The wiper 1 is rotated at a predetermined angle based on the drive of the wiper motor, and wipes raindrops and the like on the glass surface.

As shown in FIGS. 2 (a), 2 (b), 3 (a) and 4, the arm body 5 of the present embodiment has a retainer portion 5a connected to the arm head 4 (in the drawing, a region 5a). E1
), An intermediate portion 5b provided continuously to the retainer portion 5a (a region E2 in the figure), and a piece portion 5c provided continuously to the intermediate portion 5b (a region E3 in the figure).
It has. The arm body 5 is formed by pressing and bending a single plate (not shown).

The retainer portion 5a is formed in a substantially U-shaped section (see FIGS. 5 (a) and 5 (b)) in which the side plates 12 are bent at right angles at both ends in the width direction of the top plate 11 and open to the wiping surface side. ing. The base end of the retainer portion 5a is
And is rotatably connected to the arm head 4. The urging spring 6 for urging the distal end of the arm body 5 toward the glass surface side is accommodated in the base end side opening of the retainer 5a, and one end of the urging spring 6 is fixed to the retainer 5a. The other end is hung on a pin 15 fixed to the arm head 4. Further, the top plate 11 and the side plate 12 are arranged from the base end side to the tip end side (intermediate section 5b side).
The width is gradually narrowed toward.

The intermediate portion 5b is located on the tip end side (piece portion 5c).
The side plate 12 is gradually bent toward the top plate 11 so as to face the top plate 11 and the opening is gradually closed (FIG. 5C).
Then, the side plate 12 is bent until it comes into contact with the top plate 11. The intermediate portion 5b allows the side surface shape of the arm body 5 to smoothly connect from the retainer portion 5a to the piece portion 5c.

The piece portion 5c is formed such that the side plate 12 is brought into contact with the top plate 11, the opening is closed, and the side plate 12 has a substantially plate-like cross section integral with the top plate 11 (FIG. 5 (d)). )reference). Further, a hook portion 5d which is bent into a U-shape having a predetermined shape is provided on the tip end side of the piece portion 5c to be connected to the wiper blade 3.

As shown in FIGS. 4 and 5B to 5D, each side plate 12 of the arm body 5 has a retainer 5a.
, The middle part 5b and the piece part 5c
A folded portion 16 that is folded once to double the side plate 12 is provided in a region E4 in the drawing.
In the present embodiment, the folded portion 16 is formed in substantially the same shape as the side plate 12 in the region E4. By providing such a folded portion 16, each side plate 12 in the region E4 is made apparently thick,
The rigidity has been increased.

As shown in FIG. 6 (a), when the arm body 5 is stamped out by pressing, the folded-back portion 16 is
It is punched so as to be continuous to 2. Then, FIG.
As shown in (1), before bending to form the outer shape of the arm body 5, the folded portion 16 is bent so as to abut on the surface inside the side plate 12, and then the outer shape of the arm body 5 is bent. It is formed as shown in FIG.

FIG. 3B shows a change in rigidity of the arm body 5 in the longitudinal direction. Note that an actual measured value of the rigidity according to the distance from the base end of the arm body 5 (the connection portion with the arm head 4) is indicated by “X”, and an optimal value of the rigidity of the arm body 5 is indicated by “Y”.

Due to its shape, the arm body 5 of the present embodiment has a single side plate 12 without the folded portion 16 described above, that is, when the thickness of the side plate 12 is constant in the longitudinal direction.
It can be estimated from the section modulus that the rigidity of the portion (intermediate portion 5b) where the cross-sectional shape changes from substantially U-shaped (retainer portion 5a) to substantially plate shape (piece portion 5c) becomes lowest. As shown by the dashed line, it can be seen that the stiffness near the intermediate portion 5b is lower than the optimum value Y. In other words, the plate material forming the arm body 5 of the present embodiment means that a thin plate material whose rigidity near the intermediate portion 5b when the side plate 12 is made single is lower than the optimum value Y is used. I have.

Therefore, the arm body 5 of the present embodiment has the apparent thickness of the side plate 12 in the region E4 by using the inexpensive thin plate material by providing the folded portion 16 in the predetermined region E4 including the intermediate portion 5b. Is increased so that the rigidity becomes higher than the optimum value Y. In other words, the arm main body 5 of the present embodiment does not use an expensive thick plate in order to increase the rigidity of the portion where the rigidity is low (near the intermediate portion 5b) because of its shape.
Is provided to partially increase the rigidity, so that an inexpensive thin plate material can be used.

As described above, according to the present embodiment,
It has the following effects. (1) The arm body 5 of the present embodiment has
Part lower than desired rigidity (optimum value Y) (intermediate part 5b which shifts (changes) from retainer part 5a to piece part 5c)
Is provided in the predetermined area E4 including the folded portion 16 which is folded back into the opening so as to overlap the side plate 12 constituting the outer shape. By providing such a folded portion 16, the apparent plate thickness of the side plate 12 in the region E4 is increased from the plate thickness in the region other than the region E4, and the rigidity is increased. Therefore, the entire arm body 5 can be configured by using an inexpensive thin plate by increasing the rigidity partially by the folded portion 16 instead of using an expensive thick plate. Moreover, due to the folded portion 16,
Since the rigidity of the arm body 5 can be partially increased, the design of the arm body 5 in which the retainer portion 5a and the piece portion 5c are integrally formed of the same plate material does not deteriorate.

(2) As in the present embodiment, the retainer 5
a and the piece portion 5c are made of the same plate and are integrally formed with the arm body 5.
Is formed, the cross-sectional shape is substantially U-shaped (retainer portion 5
From the section modulus, it can be estimated from the section modulus that the portion (intermediate portion 5b) that changes from a) to a substantially plate shape (piece portion 5c) has the lowest rigidity, and as shown in FIG. Has been confirmed. Therefore, the folded portion 16
Is provided, the rigidity of the arm body 5 can be increased most effectively, and required strength can be secured.

(3) Since the stiffness of the arm body 5 is increased by the folded portion 16 provided integrally with the plate constituting the arm body 5, other members need not be used, and the number of parts does not increase.

(4) The folded portion 16 is folded so as to overlap the side plate 12, so that the apparent thickness of the side plate 12 is increased. Therefore, since the folded portion 16 only needs to be provided on the side plate 12, the shape of the folded portion 16 is simple and easy to form and bend.

(5) Since the folded portion 16 is folded only once, an increase in the number of bending processes of the arm body 5 can be suppressed as much as possible. (6) Since the required rigidity can be obtained even when a thin plate is used for the arm body 5 of the present embodiment, the degree of freedom in selecting the material of the plate can be improved.

The embodiment of the present invention may be modified as follows. In the above embodiment, the folded portion 16 is provided only to the side plate 12, but the folded portion 16 is formed so as to extend to the back surface of the top plate 11, and the apparent plate thickness of the top plate 11 is increased together with the side plate 12. Alternatively, the rigidity may be increased.

In the above embodiment, the folded portion 16 is provided on both side plates 12, but may be provided on only one side plate 12. In the above embodiment, the folded portion 16 is folded only once, but it may be folded twice or more.

In the above embodiment, the folded portion 16 is formed in the same shape as the side plate 12 in the region E4, but may be formed in a shape corresponding to required rigidity. In this way, necessary rigidity can be obtained without using an extra material.

In the above embodiment, the folded portion 16 is provided in the region E4 shown in the drawing to increase the rigidity of the intermediate portion 5b, but is not limited to this region E4. In the above embodiment, the arm main body 5 has a shape as shown in the drawing, but is not limited to this shape.

In the above embodiment, the present invention is applied to the wiper arm 2 of the vehicle wiper 1, but may be applied to a wiper arm other than the vehicle. The technical ideas other than the claims that can be grasped from the above embodiments will be described below together with their effects.

(A) The wiper arm according to any one of claims 1 to 3, wherein the folded portion has a shape corresponding to required rigidity. In this way, necessary rigidity can be obtained without using an extra material.

(B) A wiper for a vehicle, wherein the wiper arm according to any one of claims 1 to 3 and (a) is used. In this case, the wiper arm of the vehicle wiper can be made of a thin plate to reduce the cost, secure desired rigidity, and improve the degree of freedom in design.

[0038]

As described in detail above, according to the present invention,
It is possible to provide a wiper arm with a good-looking design while using a thin plate to reduce costs and secure desired rigidity.

[Brief description of the drawings]

FIG. 1 is a perspective view of a vehicle wiper for wiping a windshield glass (front glass) of a vehicle.

2A is a plan view of a wiper arm, and FIG. 2B is a side view of the wiper arm.

FIG. 3A is a bottom view of the wiper arm, and FIG. 3B is a diagram for explaining a change in rigidity of the arm body of the wiper arm in a longitudinal direction.

FIG. 4 is an enlarged view of a main part of FIG.

5A is a sectional view taken along line AA of FIG. 3, and FIG.
4C is a cross-sectional view taken along line BB, FIG. 4C is a cross-sectional view taken along line CC in FIG.
FIG. 5 is a sectional view taken along line DD of FIG. 4.

FIG. 6 is a view for explaining a bending process of the arm body.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 3 ... Wiper blade, 4 ... Arm head, 5 ... Arm main body, 5a ... Retainer part, 5b ... Intermediate part as a changing part, 5c ... Piece part, 6 ... Urging spring as urging means,
11: top plate, 12: side plate, 16: folded part, E4: area.

Continued on the front page (72) Inventor Takashi Hasegawa 390 Umeda, Kosai-shi, Shizuoka Prefecture Asmo Co., Ltd. F-term (reference) 3D025 AA01 AC01 AD02 AE05

Claims (3)

[Claims] An arm head fixed to a pivot shaft, a side plate rotatably connected to the arm head, and side plates bent at both ends in the width direction of the top plate to open to the wiping surface side and have a substantially U-shaped cross section. An arm body connected to a wiper blade, and a piece part having a substantially plate shape, each of which is bent so that the side plate faces the top plate, is formed integrally by bending a plate material, A wiper arm that is housed in the opening of the retainer portion and includes urging means provided between the arm head and the arm body to urge the tip end of the arm body toward the wiping surface; The arm body has a folded portion which is folded back so as to overlap with a portion constituting the outer shape in a predetermined area including a portion having a lower rigidity than the desired rigidity. A wiper arm, wherein the rigidity is increased by increasing an apparent thickness of the plate material in the region from a thickness in a region other than the region. 2. The wiper arm according to claim 1, wherein the folded portion is provided at least from a portion where the arm body changes from a retainer portion to a piece portion. 3. The wiper arm according to claim 1, wherein the turn-back portion turns back only once.