JPH01182145A - Wiper device - Google Patents

Abstract

PURPOSE:To enable holding an angle of a wiper blade and a press force at a specified value, by a method wherein a pivot shaft to rotatably hold a wiper is supported rockably along a cam surface conforming to the rotating locus of the wiper. CONSTITUTION:A tip 5A of a pivot shaft 5 is moved along a rotating locus M through rotation of a wiper along a cam surface based on a central position 6A of a ball joint. During the movement, an axial direction Q of a wiper arm 4 is moved for a short time. During rotation of the wiper, a blade deflection angle alpha of the axial direction of a wiper blade 3 with the direction of the normal of a window glass 2 can be held so that it is linearly changed in a range of a fine angle on both sides in the direction of the normal. As noted above, a given change in the blade deflection angle alpha is ensured so that inversion of the wiper blade 3 is smoothly effected during rotation of the wiper. Since it is desirable that the press force of the blade 3 on a glass 2 is specified throughout the total contact surface of the blade 3, the depress angle of the blade is set to zero.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a wiper device used for wiping a windshield of an automobile, for example.

(Prior art) Conventionally, as this type of wiper device, for example,
The one described in Japanese Patent No.-122266 is known. According to this publication, a pivot shaft for rotatably holding a wiper is pivotally supported so as to be swingable along a guide groove substantially along the wiping direction of the wiper blade.

(Problem to be Solved by the Invention) However, according to the configuration of the prior art, the pivot shaft is swingable only in a predetermined direction. ) or the pressing force of the wiper blade against the wiping surface cannot be kept constant, and vibration noise caused by differences in the angle or pressing force, and deterioration of the wiper blade due to this, can be prevented. The problem was that it was not possible.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wiper device that can correct the angle formed by the wiper blade with respect to the wiped surface and the suppressing force of the wiper blade to keep it constant within a desired range by adding a simple configuration. .

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a pivot shaft that rotatably holds a wiper so as to be able to freely swing along a cam surface corresponding to a rotation locus of the wiper. Features (functions): The pivot shaft swings along the cam surface corresponding to the wiper rotation locus, so it is possible to make corrections to keep the angle of the wiper blade relative to the wiper surface within a predetermined range. While it is possible to correct the pressure force on the blade to keep it constant within a predetermined range, by forming the cam surface into a predetermined shape, the pressure force on the wiper blade only at the desired rotational position of the wiper, such as the reversed position, is reduced. be able to.

(Example) As shown in FIG. 4, the wiper device 1 according to the present invention is applied to a windshield 2 on the driver's seat side of an automobile as a wiping surface, for example, and includes a wiper comprising a wiper blade 3 and a wiper arm 4; It is roughly composed of a pivot 11115. Details of the vicinity of the pivot axis 5 are shown in Figures 1 and 2.
As shown in the figure, the tip of the pivot shaft 5 (upper end in Figure 1)
The wiper arm 4 is connected to the wiper arm 4, and a link 7 having a ball joint 6 connected to a wiper drive source (not shown) is connected to the base end (lower end in FIG. 1). Further, a bulge 5a is formed in the middle of the pivot shaft 5, and the bulge 5a is located inside a storage section 8a of the lower case 8, and a bush 9 is filled in the storage section 8a. ing.

Furthermore, an upper case 10 is provided on the upper part of this lower case 8.
is placed with the sealing ring () interposed, and both cases 8.
10 is fixed to the vehicle body II via bolts 12,
Rubber boots 13 and 14 are installed between the lower case 8 and the base end of the pivot shaft 5, and between the upper case 10 and the upper end of the pivot shaft 5, respectively.

On the other hand, above the bulge 5a, a wiping locus cam 15 is installed so as to pass through the pivot shaft 5 and be sandwiched between the cases 8 and 1O.
There are three trochanters 16 on the cam surface 15a of No. 5 (see Fig. 3).
The trochanters 16 are attached to leg portions 18 extending in three directions at equal intervals from a support base 17 via bearings. A spring 21 is interposed between the support base 17 and a spring seat 20 fixed to the pivot shaft 5 by a clip 19, and the action of this spring 21 causes each trochanter 16 to It can be in pressure contact with the cam surface 15a at all times.

Next, the operation of the above-described embodiment configured in this manner will be explained with reference to FIGS. 5 to 8.

First, as shown in FIG. 5, the tip 5A of the pivot shaft 5 moves along a rotation locus M by rotation of the wiper along the cam surface 15a with the center position 6A of the ball joint 6 as a reference. During this period (from the wiper starting position L1 to the wiper reversing position, while the rewiper rotation angle θ changes)
, the axial direction Q of the wiper arm 4 gradually moves in the direction shown in the figure.

During this rotation of the wiper, as shown in FIG. It can be maintained so that it varies linearly within a small angle (for example, 3 degrees) on both sides of the line (see straight line a in FIG. 8).

Note that the curve C shows the change in the blade deflection angle α when the pivot shaft 5 is not oscillated, and the curve C is a correction curve for obtaining the straight line a marked 0; J by the oscillation of the pivot shaft 5. be. The purpose of ensuring a predetermined change in the blade deflection angle α in this way is to ensure smooth reversal of the wiper blade 3 when the wiper rotates.

On the other hand, as shown in FIG. 7, the direction along the axial direction of the wiper arm 4 around the rotation center F (the direction in which the wiper blade 3 presses against the surface of the windshield 2 in the vertical force direction)
The angle at which the blade is displaced (hereinafter referred to as the blade depression angle β) is constant as shown by the base line d in FIG. That is, since it is desirable that the pressing force (blade pressure) of the wiper blade 3 against the windshield 2 be constant over the entire contact surface of the wiper blade 3, the blade depression angle β is set to zero. In addition, in FIG. 8, the curve e is the pivot axis 5.
1III line f is a correction curve for obtaining the base line d indicated by njI by swinging the pivot shaft 5. This correction curve f, together with the correction curve C, becomes the basis for forming the cam surface 15a.

As shown in FIG. 8, clearance angles γ1 and γ are provided near the wiper starting position 1 and the wiper reversing position L8, respectively, in order to ensure smooth rotation of the wiper.

is set. Also, in both positions 9 and L, cam surface 1
By forming 5a into a predetermined shape, the blade pressure can be reduced and smoother rotation of the wiper can be ensured.

<Effects of n Light> As described above, according to the present invention, the pivot shaft that rotatably holds the wiper is pivotally supported so as to be freely swingable along the cam surface corresponding to the rotation locus of the wiper. Since the configuration is
At any rotational position of the wiper, it is possible to correct the angle change made by the wiper blade relative to the wiped surface within a predetermined range, and to keep the pressing force of the wiper blade constant at all times.Moreover, both corrections can be made simultaneously. Because it can be done,
It is possible to effectively prevent unpleasant chattering noises occurring between the wiping surface and the wiper blade.

Further, the pressure of the wiper blade can be reduced at a desired position, and the durability of the wiper device can be improved.

[Brief explanation of the drawing]

Figure 1 and Figure fA2 show one embodiment of the present invention.
FIG. 1 is a longitudinal cross-sectional view of the main part, FIG. 2 is a cross-sectional view taken along the line ■-H in FIG. 1, and FIG. 3 is a perspective view of the wiping locus cam shown in FIG. 1.
FIG. 4 is a perspective view of essential parts showing the front part of an automobile to which the wiper device of the present invention is applied, FIG. 5 is a schematic diagram showing the locus of the tip of the pivot shaft, and FIG. 6 is a schematic diagram illustrating the blade deflection angle. Figure 7 is a schematic diagram explaining the blade depression angle, Figure 8 is a schematic diagram explaining the blade depression angle.
The figure is a graph showing the relationship between the rotation angle of the wiper, the blade deflection angle, the blade depression angle, etc. l... Wiper device, 3... Wiper blade (wiper), 4... Wiper arm (wiper), 5... Pivot shaft, 15... Rotation locus cam. Applicant: 1 Giken Kogyo Co., Ltd.

Claims (1)

[Claims] 1. A wiper device characterized in that a pivot shaft that rotatably holds a wiper is pivotally supported so as to be swingable along a cam surface corresponding to a rotation locus of the wiper.