JPH0516766A - Wiper device - Google Patents

Abstract

PURPOSE:To improve operability of lock back in a lock back mechanism holding a wiper arm in the condition of separating a wiper blade from a window glass face by providing a link mechanism, and enabling a pressing angle to be reduced. CONSTITUTION:A reciprocatively oscillated arm head 16 arranged on the one end of a wiper arm 11 is provided with a hinge 18, and the one end part 20A of a retainer 20 constituting the one part of the wiper arm 11 is supported with the hinge 18. A first link 31 is borne with the bearing 28 of the arm head 16 through a shaft 30, and the shaft 36 of the first link 31 is inserted to the bearing 42 of a second link 40. The shaft 46 fixed to the retainer 20 is inserted to the bearing 44 of the second link 40, and a stopper shaft 48 to hold a wiper blade 26 in lock back condition is provided on the retainer 20. Further the pin 50 of the first link 31 is locked with the one end of a tension coil spring 52, so as to give the wiper arm 11 the energization force in the window glass direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiper device, and more particularly to a wiper device having a lockback mechanism for a wiper arm.

[0002]

2. Description of the Related Art Conventionally, a wiper device mounted on a vehicle such as an automobile has a wiper blade attached to a wiper arm, the wiper arm is swung in a plane substantially parallel to the window glass surface, and the window glass is wiped by the wiper blade. It is like this. Further, the wiper device includes a wiper arm in a state where the wiper blade is away from the window glass surface when the wiper is not used for a long time, when the window glass is cleaned without using the wiper, or when the wiper blade is replaced. It is equipped with a so-called lockback mechanism for holding.

As an example of the lockback mechanism of this wiper device, US Pat. No. 4,741,068 is disclosed. As shown in FIG. 9, in this wiper device 70, the other hook 72B of the tension coil spring 72 in which one hook 72A is engaged with the hook portion 71A of the wiper arm 71 has one end portion 74A of the spring guide 74. Is engaged with. This spring guide 74
Has an inverted V shape in order to avoid interference with the hinge 76 in the locked back state (state of imaginary line in FIG. 9), and the other end portion 74 B of the spring guide 74 is a tension coil with respect to the hinge 76. It is engaged with a portion opposite to the spring 72.

[0004]

However, in this lockback mechanism, the straight line S connecting the engagement point P1 of the end portion 74B of the spring guide 74 and the engagement point P2 of the hook 72A of the coil spring 72 is the hinge 76. The tension force of the tension coil spring 72 urges the wiper arm 71 in the lockback state when it moves above the axis. Therefore, the pressing angle (the angle formed by the straight line S and the perpendicular line H from the axial center of the hinge 76 to the window glass) α for bringing the wiper arm 71 into the lockback state becomes large, and the lockback operability is not good. was there.

In view of the above facts, the present invention has an object to provide a wiper device capable of improving lockback operability.

[0006]

According to a first aspect of the present invention, a wiper arm supported by a hinge formed on an arm head so as to be swingable in a direction substantially perpendicular to a window glass surface is provided on the arm head. First pivotally supported on a pivoting shaft that is pivotable in the pivoting direction of the wiper arm
, A pin provided on the first link at a position offset from the rotating shaft in the direction of the window glass, an elastic body connecting the pin and the wiper arm, and the wiper arm on the shaft provided on the wiper arm. A second link that is swingably supported in the swinging direction and is rotatably connected to the first link via a shaft, and a stopper that holds the wiper arm in a lockback state. It is characterized by that.

[0007]

According to the present invention as set forth in claim 1, the pulling force of the elastic body acts on the wiper arm, and the wiper arm mounting portion of the wiper arm is provided with a force F1 for constantly urging the wiper arm toward the window glass with the hinge as the center of rotation. give. At the same time, the tensile force of the elastic body acts on the pin of the first link to give the first link a rotational force about the rotation axis. This rotational force is transmitted in the order of the shaft connecting the first link and the second link and the second link,
A force F2 for urging the wiper arm in the direction toward the window glass or in the direction opposite to the window glass is applied through the shaft provided on the wiper arm with the hinge as the center of rotation.

This force F2 is applied to the first link and the second link when the pressing angle of the wiper arm is increased, that is, when the wiper arm is swung in the direction opposite to the window glass.
It is configured to decrease with the link of, and when the pressing angle of the wiper arm becomes larger than a predetermined value,
It acts as a rotational force that urges the wiper arm in the direction opposite to the window glass.

Therefore, when the wiper arm is swung in the direction opposite to the window glass by the operation of the operator, the force F is applied.
2 further decreases, and then the force F2 increases as a rotational force that urges the wiper arm in the direction opposite to the window glass.

Therefore, the pulling force of the elastic body causes the wiper arm holding force F = F1 + F acting on the wiper blade mounting portion of the wiper arm with the hinge as the center of rotation.
In No. 2, when the pressing angle of the wiper arm increases and the absolute value of the force F2 exceeds the force F1, the hinge is used as the center of rotation,
It acts as a rotational force that swings the wiper arm in the direction opposite to the window glass. Further, the swinging of the wiper arm in the direction opposite to the window glass due to this rotational force is stopped by the stopper, and the wiper arm enters the lockback state.

As described above, according to the present invention, since the link mechanism is used, the pressing angle for bringing the wiper arm into the lockback state can be made small and the lockback operability can be improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 3, the wiper arm 11 of the wiper device 10 of the present embodiment is arranged on the window glass 12 in the clockwise direction of FIG. 3 (the arrow X direction in FIG. 3) and in the direction opposite to the clockwise direction (FIG. 3). 3, and the window glass 12 is wiped by the blade 14 attached to the tip.

As shown in FIG. 4, an arm head 16 is arranged at one end of the wiper arm 11.
The arm head 16 is connected to a swing means (not shown) and is swingable in the arrow X direction and the arrow Y direction in FIG. The arm head 16 has a hinge 1
8 are provided. The hinge 18 has one end 20A of a retainer 20 that constitutes a part of the wiper arm 11.
Is supported, and the retainer 20 can swing about the hinge 18 in the clockwise direction of FIG. 4 (direction of arrow P in FIG. 4) and the direction opposite to the clockwise direction (direction of arrow S in FIG. 4). It is said that. In addition, the other end 20 of the retainer 20
An arm piece 22 that constitutes another part of the wiper arm 11 is fixed near B. This arm piece 2
2 extends along the window glass 12 and has a tip 2
A blade 26 is attached to 2A via a hinge 24.

As shown in FIGS. 1 and 2, the arm head 16 is provided with an extending portion 16A extending toward the window glass 12 side of the hinge 18, and a bearing 28 is driven into the extending portion 16A. Has been. A shaft 30 is inserted into the bearing 28, and a first link 31 is fixed to the shaft 30. The first link 31 is composed of two plate members 32 and 34 arranged in parallel with each other with the extending portion 16A of the arm head 16 interposed therebetween.
It is swingable around the shaft 30. First
At the end of the link 31 of the blade 26 side, the shaft 36
The shaft 36 is provided with a bearing 4 that is driven into the end of the second link 40 on the arm head 16 side.
It is inserted in 2.

The bearing 4 is provided at the center of the second link 40.
4 has been hammered in. A shaft 46 is inserted into the bearing 44, and both ends of the shaft 46 are fixed to the retainer 20. A stopper shaft 48 is provided on the blade 26 side of the shaft 46 of the retainer 20.
When the link 40 of the second link 40 swings counterclockwise, the end portion 40 of the second link 40 on the blade 26 side is attached to the stopper shaft 48.
A contacts.

A pin 50 is fixed to the end of the first link 31 opposite to the blade 26. One hook portion 52A of the tension coil spring 52 as an elastic body is engaged with the pin 50, and the other hook portion 52B of the tension coil spring 52 is provided on the arm head 16 side end portion of the arm piece 22. It is engaged with the hook 22B.

Next, the operation of this embodiment will be described.
As shown in FIG. 4, when the tension force by the tension coil spring 52 is T, the tension force T is
Rotational force T in the direction of arrow P in FIG. 4 is applied to the retainer 20 with the hook 22B of No. 2 as an application point and the hinge 18 as the center of rotation.
Give A. In this case, A is the tension coil spring 52
Is the distance between the axis of the and the axis of the hinge 18.

Therefore, when this rotational force TA is divided by the distance (arm length) L between the axis of the hinge 18 and the blade 26 mounting portion (the axis of the hinge 24) of the tip 22A of the arm piece 22, the tip of the arm piece 22 is divided. The force F1 acting on the portion 22A in the direction of the window glass 12 is TA / L.

At the same time, the tensile force T gives a rotational force TB in the direction of arrow P in FIG. 4 with the pin 50 of the first link 31 as the force application point and the shaft 30 as the center of rotation. In this case, B is the axis of the tension coil spring 52 and the shaft 3
It is the distance from the axis of 0.

Therefore, this rotational force TB is applied to the shaft 30 and the extension line of the line connecting the center of the shaft 36 and the center of the shaft 46.
Divided by the distance C from the axis of the retainer 2 through the shaft 46
At 0, the force TB / C acts in the direction of arrow Q in FIG. This rotational force TB / C gives the retainer 20 a rotational force DTB / C in the direction of arrow P in FIG. 4 with the shaft 46 as the force application point and the hinge 18 as the center of rotation. In this case, D is the distance between the extension of the line connecting the center of the shaft 36 and the center of the shaft 46 and the axis of the hinge 18.

Therefore, when this rotational force DTB / C is divided by the arm length L, the force F2 = DTB acting on the tip portion 22A of the arm piece 22 toward the window glass 12 is obtained.
/ CL. Therefore, the tip portion 2 of the arm piece 22
The wiper arm pressing force F acting on 2A is F = F1 + F
It becomes 2.

Further, the arm pressing force F2 has a large arm pressing angle θ (an angle formed by a perpendicular line drawn from the axis of the hinge 18 to the window glass 12 and a line connecting the axis of the hinge 18 and the axis of the hinge 24). As shown in FIG. 5, the center of the shaft 36 and the axis 46
When the extension line of the line connecting the centers of the two is located on the opposite side of the window glass 12 from the axis of the hinge 18, it becomes negative. That is, F2 = -DTB / CL, and acts on the tip portion 22A of the arm piece 22 in the direction opposite to the window glass 12.

Further, as shown in FIG. 6, when the arm pressing angle θ is further increased by the operation of the operator, F2
Becomes larger than the absolute value of F1, and the wiper arm pressing force F = F1 + F2 acts on the tip portion 22A of the arm piece 22 in the direction opposite to the window glass 12. Therefore, the retainer 20 is swung in the direction of arrow S in FIG.
The end portion 44A of the second link 40 on the blade 26 side abuts. As a result, the retainer 20 is held in the lockback state where the arm pressing angle is θ3.

As described above, in this embodiment, since the link mechanism is used, the pressing angle for bringing the wiper arm 11 into the lockback state can be made small and the lockback operability can be improved.

Further, according to this embodiment, the holding force is set in order to hold the wiper arm in the lockback state by utilizing the tension of the tension coil spring 52 provided for pressing the wiper arm against the window glass 12. Can be performed easily and reliably. Further, in order to hold the wiper arm in the lockback state, the holding load may be set to a value that slightly exceeds the own weight of the retainer 20, the arm piece 22, and the blade 26. Since the holding load does not change with time, the holding load is extremely small. It is possible to set a low value, and the operability of the wiper arm is improved.

In the lockback state of the wiper arm, since the stopper shaft 48 only comes into contact with the second link 40 and there is no need for a lap margin that occurs when the link and the stopper are engaged, the wiper arm is held. The angle can be set small. Further, as shown in FIG. 7, the wiping is performed by determining the shapes and attachment positions of the first link 31 and the second link 40 so that the wiping is performed within the range where the arm pressing force is substantially constant. The performance can be improved.

Although the retainer 20 is provided with the stopper shaft 48 in the above embodiment, instead of this, as shown in FIG. 8, the stopper 54 is formed on the arm head 16, and the stopper 16 is formed at the end of the retainer 20. It may be configured to contact the portion 20A.

[0029]

Since the present invention has the above-mentioned structure, it has an excellent effect that the lockback operability can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a wiper device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a front view showing a window glass to which a wiper device according to an embodiment of the present invention is applied.

4 is a cross-sectional view taken along line 4-4 of FIG.

5 is a cross-sectional view taken along line 5-5 of FIG.

FIG. 6 is a cross-sectional view showing a lockback state of the wiper device according to the embodiment of the present invention.

FIG. 7 is a graph showing the relationship between the wiper arm pressing angle and the wiper arm pressing force of the wiper device according to the embodiment of the present invention.

FIG. 8 is a sectional view showing a wiper device according to another embodiment of the present invention.

FIG. 9 is a cross-sectional view showing a wiper device according to a conventional example.

[Explanation of symbols]

 10 Wiper Device 11 Wiper Arm 12 Window Glass 14 Blade 16 Arm Head 18 Hinge 20 Retainer 22 Arm Piece 30 Shaft (Rotating Axis) 31 First Link 36 Shaft 40 Second Link 46 Axis 48 Stopper Axis 50 Pin 52 Tension Coil Spring (Elastic body)

Claims (1)

Claim: What is claimed is: 1. A wiper arm supported by a hinge formed on an arm head so as to be swingable in a direction substantially perpendicular to a window glass surface, and a rotary shaft provided on the arm head. A first link that is swingably supported in the swing direction of the wiper arm, a pin provided at the first link at a position offset from the rotation axis in the window glass direction, and the pin and the wiper arm are connected. An elastic body, and a second link rotatably supported by a shaft provided on the wiper arm in the swing direction of the wiper arm and rotatably connected to the first link via a shaft. And a stopper that holds the wiper arm in a lockback state.