JP2762597B2 - Wiper device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention can reduce a pressing force on a wiping surface of a wiper device, particularly a wiper device used for an automobile or a ship, in a wiper blade reversal region. The present invention relates to improvement of a wiper device.

[Prior Art] In this type of wiper device, in order to exhibit its wiping performance, it is necessary to press a wiper blade against a window panel with a predetermined pressing force.
At the reversing position of the reciprocatingly oscillating wiper arm, reducing the pressing force of the wiper blade against the window panel is useful for quickly reversing the oscillating direction of the wiper blade and preventing generation of abnormal noise at the time of reversal.

As a countermeasure for this, there is, for example, one disclosed in Japanese Patent Laid-Open No. 60-80958.

However, in this technique, the pressing force of the wiper blade against the window panel continuously changes depending on the operating angle of the wiper arm. It is desirable that the pressing force be reduced only at the reversing position, and that a predetermined pressing force be secured at other portions to maintain the wiping performance.

Therefore, as a technique capable of reducing the pressing force only at the reversing position, for example, a technique as shown in FIGS. 7 to 11 has been proposed (Japanese Patent Application No. 1-61228). In this wiper device, as shown in FIG. 7, a wiper arm 2 is attached to a pivot shaft 1, and a wiper blade 4 for wiping the surface of the window panel 3 is attached to the wiper arm 2.

Specifically, the wiper arm 2 is provided with an arm head 5,
The arm head 5 includes a retainer 6 and an arm piece 7. A base end 5 a of the arm head 5 is fixed to the pivot shaft 1, and a base end 6 a of the retainer 6 swings at a distal end 5 b of the arm head 5. It is attached so as to swing in a plane perpendicular to the window panel 3 via the driving shaft 8.

Further, a tension spring 9 is disposed between the rear end portion 7a of the arm piece 7 and the arm head 5 via a pressing force adjusting device 10, as shown in FIG.

More specifically, in the pressing force adjusting device 10, as shown in FIG. 8, a turning member 11 is provided on the arm head 5 via a bearing 12 so as to be rotatable. This rotating member 11 is
a, a holding portion 11b extending in a direction orthogonal to the shaft portion 11a, a large lever 11c, and a small lever 11d. A shaft portion 11a of the rotating member 11 is rotatably supported by the bearing 12, and one end of a tension spring 9 is connected to a holding portion 11b of the rotating member 11 via a hook member 13. I have.

On the other hand, on the vehicle body side, a pressing member (not shown) for pressing and rotating the large lever 11c and the small lever 11d of the rotating member 11 is disposed at the position where the wiper arm 2 is inverted.

According to this, the window panel 3 is wiped at a predetermined wiping angle, and the wiper blades 4 are inverted at both ends of the wiping area.

At the time of wiping, the wiper blade 4 is urged in the direction of pressing against the surface of the window panel 3 by the tensile force of the tension spring 8, and the wiping is performed following the surface of the window panel 3 which is convex. I can do it.

When the wiper arm 2 reaches the vicinity of the reversing position, the large lever 11c of the rotating member 11 contacts the pressing member and rotates as shown by the arrow in FIG. By this rotation, the holding portion 11
b is rotated about the shaft portion 11a, and the tension direction by the tension spring 9 is changed. As a result, the moment acting on the wiper blade 4 toward the window panel 3 around the swing shaft 8 is reduced, and the reversal sound when the wiper arm 2 is reversed is reduced. On the other hand, when the swinging of the wiper arm 2 in the reverse direction starts, the pressing member comes into contact with the small lever 11d, and the rotating member 11
Is returned to the neutral position.

[Problem to be Solved by the Invention] However, in the wiper device having such a structure, when the wiper arm 2 is at the reverse position, the large lever 11c is pressed by the pressing member disposed on the vehicle body side to rotate. Since the engagement length between the large lever 11c and the pressing member cannot be increased, the rotation angle of the rotation member 11 cannot be increased so much, and the rotation of the rotation member 11 with respect to the wiper arm 2 rotation amount. Since the rotation angle ratio cannot be set large, it is difficult to sufficiently obtain the effect of reducing the pressing force of the wiper blade 4 at the time of reversal. In order to return the rotating member 11 to the neutral position, the pressing member and the small lever 11 are used.
Since the meshing with d is used, there is a problem that the meshing accuracy is also required.

[Means for Solving the Problems] The present invention has been made to solve such a conventional problem, and a base end of a retainer is connected to a distal end of an arm head fixed to a pivot shaft via a swing shaft. By attaching one end of a tension spring to the retainer and locking the other end of the tension spring to the arm head, a pressing force in the direction of the window panel is applied to the wiper blade mounted on the retainer. In the wiper device, at the wiper blade reversal position, a pressing force adjusting device that changes the pulling direction of the tension spring to reduce the pressing force is provided, and the pressing force adjusting device includes a shaft portion having a pinion portion formed therein and the shaft portion. A holding portion extending from the shaft portion in a direction substantially perpendicular to the shaft portion and holding the other end of the tension spring; A rotatable member rotatably supported on the retainer in a direction substantially extending the retainer, a rack portion meshed with the pinion portion, and a pressed portion extending toward the window panel, and the shaft portion direction. A drive member slidably disposed in a direction substantially perpendicular to the direction, and disposed so as to be able to return to a neutral position by a biasing unit;
The wiper device is characterized in that the wiper device is provided with a pressing member that protrudes in the vicinity of the wiper reversal position on the vehicle body side and that presses and slides the pressed portion of the driving member.

[Operation] According to this means, the wiper blade is swung about the pivot axis, and the window panel surface is wiped. In this case, due to the tension of the tension spring,
The wiper blade is pressed against the window panel surface and wiped.

When the wiper arm approaches the reversing position, the pressing member provided on the vehicle body contacts the pressed portion of the driving member. Then, with the swing of the wiper arm, the driving member slides in a direction substantially perpendicular to the shaft direction, and the rotating member is rotated via the pinion in the rack of the driving shaft. .

As a result, the holding portion of the rotating member is rotated, the tension direction of the tension spring is changed, and the pressing force of the wiper blade about the pivot axis is reduced, so that the reverse noise is reduced.

When the swinging of the wiper blade in the reverse direction starts, the driving member returns to the neutral position by the urging means, and the locking portion of the rotating member also returns to the neutral position via the pinion portion.

As described above, according to the present invention, the driving member is slidable, and the rotating member is rotated via the pinion portion by the rack portion provided on the driving member. Unlike the one that rotates, the meshing state of the pressed member of the driving member by the pressing member can be lengthened, and the setting of the gear ratio between the pinion portion and the rack portion allows the rotation member to rotate with respect to the wiper arm rotation angle. Since the ratio of the rotation angles can be increased, the pressing force at the time of inversion can be reduced as compared with the related art, so that the inversion sound can be further reduced and the inversion operation can be performed quickly.

In addition, since the rotating member is returned to the neutral position by the urging means, and is not used for engagement with the small lever 11d or the like as in the related art, it is possible to return to the neutral position with a simple structure. [Example] Hereinafter, the present invention will be described based on an example.

1 to 6 show an embodiment of the present invention.

First, the structure of the wiper device will be described. As in the prior art, a wiper arm 2 is mounted on a pivot shaft 1 and a wiper blade 4 for wiping the surface of a window panel 3 is mounted on the wiper arm 2.

Specifically, the wiper arm 2 is provided with an arm head 5,
The arm head 5 includes a retainer 6 and an arm piece 7. A base end 5 a of the arm head 5 is fixed to the pivot shaft 1, and a base end 6 a of the retainer 6 swings at a distal end 5 b of the arm head 5. It is attached so as to swing in a plane perpendicular to the window panel 3 via the driving shaft 8.

Further, between the rear end portion 7a of the arm piece 7 and the arm head 5, as shown in FIG. 8, a tension spring 9 is provided with a pressing force adjusting device 20 for reducing the pressing force at the position where the wiper blade 4 is reversed. It is arranged through.

Specifically, as shown in FIG. 1, in the pressing force adjusting device 20, first, a rotating member 21 is rotatably provided on the arm head 5 via a bearing 22. This rotating member 21
The shaft portion 21a includes a holding portion 21b extending in a direction orthogonal to the distal end side of the shaft portion 21a, and a pinion portion 21c formed on the base end side of the shaft portion 21a. A shaft portion 21a of the rotating shaft portion 21 is rotatably supported by the bearing 22, and one end of the tension spring 9 is connected to a holding portion 21b of the rotating member 21 via a hook member 23. . This hook member 23
Is rotatably loosely inserted into an insertion hole 21d formed in the holding portion 21b of the rotating member 21 so that the head 23a cannot be pulled out. The hook 23b of the hook member 23
Is hooked on one end of the tension spring 9.

Further, on the pinion portion 21c side of the rotating member 21, a driving member 24 for rotating the rotating member 21 is provided.

As shown in FIG. 3, the driving member 24 is provided on the upper surface of a rectangular plate-shaped driving member main body 24a.
While a rack portion 24b screwed to 1c is formed, a pressed piece 24c as a pressed portion is vertically projected downward from the drive member main body 24a. Then, slide pieces 24d are formed on both side surfaces of the drive member main body 24a, and the slide pieces 24d are formed in slide grooves 5 formed in the arm head 5.
The drive member 24 is set so as to slide in a direction substantially perpendicular to the shaft portion 21a by being slidably inserted into c. The sliding of the driving member 24 causes the rotating member 21 to rotate. Further, the driving member 24 is set so as to always return to the neutral position as shown in FIG. 3 by a spring 25 as a biasing means provided between the driving member 24 and the arm head 5.

On the other hand, on the vehicle body side, a pressing member 26 for pressing and rotating the pressed piece 24c of the driving member 24 is disposed at a predetermined position near the wiper arm 2 reversing position (see FIG. 5).

Next, the operation of the wiper device having such a configuration will be described.

When the wiper motor 4 (not shown) swings the wiper blade 4 about the pivot shaft 1 via the wiper arm 2, the wiper blade 4 wipes the convex surface of the window panel 3. In this case, the retainer 6 is rotated toward the surface of the window panel 3 by the tensile force of the tension spring 8, and the wiper blade 4 is pressed against the surface of the window panel 3 to be wiped. At positions other than the reversing position, as shown in FIG. 4 (d), since the holding portion 21b is in a substantially vertical direction toward the window panel 3, the window panel is attached to the wiper blade 4 around the swing shaft 8. The moment M ₀ acting toward the third side is, as shown in FIG. 4B, M ₀ = F · L _0, where F is the tension force of the tension spring 9 and L ₀ is oscillating from the tension spring 9 This is the distance to axis 8.

Then, when the wiper arm 2 approaches the reversing position,
A pressing member 26 provided on the vehicle body contacts the pressed portion 24c of the driving member 24. In this state, as the wiper arm 2 swings, the driving member 24 is pressed by the pressing member 26, guided by the slide groove 5c, and resists the urging force of the spring 25, as shown in FIG. Slided. This allows
The rotating member 21 is rotated by the rack portion 24b of the driving member 24 via the pinion portion 21c, and the holding portion 21b of the rotating member 21
Is rotated about the shaft portion 21a as shown in FIG. 5D, whereby the tension direction of the tension spring 9 is changed. Then, as shown in FIG. 5 (b), since the distance L ₁ to the pivot shaft 8 decreases from tension spring 9, toward the window panel 3 side to the wiper blade 4 around the pivot shaft 8 The acting moment M ₁ is M ₁ = F · L ₁ , and M ₁ is smaller than M ₀ .

Accordingly, since the pressing force of the wiper blade 4 is reduced at the reversing position, the reversing sound is reduced and the reversing operation can be performed quickly.

If this is compared with the previously proposed one, it will be as shown in FIGS. 6 (a) and 6 (b). FIG. 6A is a graph showing a change in the rotation angle θ of the rotating member 21 with respect to the amount of movement x of the pressed piece 24c of the driving member 24 (the amount of movement of the arm head 5). FIG. 6B shows a pressing ratio (P / P ₀ ) of the wiper blade 4 to the moving amount x.
FIG. 7 is a graph showing changes in (P ₀ is a specified pressing force, P is an actual pressing force).

According to this, if the length of the pressing member is set to be longer than that of the large lever 11c and the meshing state of both is ideally set, a line as shown by a one-dot chain line A is drawn in the figure.
According to this, when the movement amount x becomes the length L of the large lever 11c, the rotating member 21 rotates π / 2 as shown in FIG.
In this state, the pressing ratio P / P ₀ becomes 0 as shown in FIG. However, the one shown by the one-dot chain line A in the figure is ideal, and in reality, the rotation angle θ with respect to the moving amount x becomes small as shown by the broken line B in the figure due to the relationship of meshing and the like,
The pressing ratio P / P ₀ increases. On the other hand, according to this embodiment, as shown by the solid line C in the figure, the rotation angle θ increases and the pressing ratio P / P ₀ decreases. That is, according to this embodiment, by setting the gear ratio between the pinion portion 21c and the rack portion 24b to a predetermined value, the change in the rotation angle θ with respect to the movement amount x can be set to be larger than that shown by the one-dot chain line A. , The pressing ratio P / P ₀ can be reduced. Therefore, the pressing force at the time of reversing the wiper arm 2 can be made smaller than that proposed above, which leads to a reduction in reversal sound and a quick reversal operation.

[Effects of the Invention] As described above, according to the present invention, the pressing force adjusting device is provided with the shaft portion on which the pinion portion is formed, and the pressing force adjusting device extends in a direction substantially orthogonal to the shaft portion, and the other end of the tension spring is provided. A rotating member rotatably supported by the arm head about the extension direction of the retainer, a rack portion meshed with the pinion portion, and a shaft portion extending to the window panel side; A drive member having a pressed portion, slidable in a direction substantially perpendicular to the axis direction, and arranged to be able to return to a neutral position by a biasing means; By using a pressing member that presses and slides the pressed portion of the driving member,
This has a practically useful effect that the inversion sound at the time of inversion of the wiper blade can be reduced as compared with the conventional case.

[Brief description of the drawings]

1 to 6 are views showing an embodiment of a wiper device according to the present invention. FIG. 1 is a sectional view of a main part of the wiper device.
FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG.
4 (a) to 4 (d) are views showing states other than the wiper arm reversal position, and FIG. 4 (a) is a view showing the position of the wiper arm with respect to the window panel. FIG. 5B is an explanatory view showing the relationship between the tension spring and the rotating member and the like, and FIGS. 5C and 5D are views shown by arrows A and B in FIG. (A) to (d)
FIGS. 4 (a) to 4 (d) correspond to the wiper arm reversing position, and FIG. 6 (a) is a graph showing the relationship between the movement amount x of the pressed piece and the rotation angle θ of the rotating member. FIG. 6 (b) is a graph showing the relationship between the movement amount x and the pressing ratio, FIGS. 7 to 11 are views showing a conventional example, FIG. 7 is a perspective view of a wiper device, and FIG. FIG. 8 is VIII- of FIG.
9, 10, and 11 are sectional views taken along lines IX-IX, XX, and XI-XI in FIG. 8, respectively. DESCRIPTION OF SYMBOLS 1 ... Pivot shaft 2 ... Wiper arm 3 ... Window panel 4 ... Wiper blade 5 ... Arm head 6 ... Retainer 7 ... Arm piece 8 ... Swing shaft 9 ... Tension spring 20 ... Pressing force adjusting device 21 ... Rotating member 21a ... Shaft Portion 21b Holding portion 21c Pinion portion 24 Drive member 24b Rack portion 24c Pressed piece (pressed portion) 25 Spring (biasing means) 26 Pressing member

────────────────────────────────────────────────── ─── Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B60S 1/04-1/42

Claims (1)

(57) [Claims] 1. A base end of a retainer is attached to a distal end of an arm head fixed to a pivot shaft via a swing shaft, and one end of a tension spring is locked to the retainer, and the other end of the tension spring is connected to the retainer. A wiper blade attached to the retainer, which applies a pressing force in the direction of the window panel to the wiper blade mounted on the retainer. A pressing force adjusting device for reducing pressure is provided, and the pressing force adjusting device extends in a direction substantially perpendicular to the shaft portion on which the pinion portion is formed, and holds the other end of the tension spring. A rotating member having a holding portion, the shaft portion being rotatably supported by the arm head about a substantially extending direction of the retainer; A rack portion meshed with the shaft portion and a pressed portion extending toward the window panel, slidable in a direction substantially perpendicular to the axial direction, and capable of returning to a neutral position by a biasing means. A wiper device comprising: a driving member provided; and a pressing member projecting from the vehicle body near the wiper reversing position and pressing and sliding a pressed portion of the driving member.