JP2923724B2 - Automatic inertia adjustment mechanism of wiper device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiper device having a wiper arm reciprocatingly tilting around a wiper shaft, and having a structure in which the reciprocating tilting cycle of the wiper arm is adjusted. The present invention relates to a mechanism improved to automatically suppress energy fluctuation and maintain a normal wiping operation.

[0002]

2. Description of the Related Art The basic configuration of a wiper device is as shown by a solid line in FIG. 2, in which a wiper head (5) is mounted on a wiper shaft (8) and a reciprocating circular arrow (θ). As described above. A wiper arm (7) is rotatably mounted on the wiper head (5) by a pivot (6) perpendicular to the wiper shaft. A wiper blade (not shown) is supported by a tip end of a wiper arm (7) that is reciprocated about the wiper shaft (8) by the above configuration, and the wiper blade wipes the window glass surface.
The above-mentioned wiper device is mainly used in rainy weather,
A wiper device having a structure in which a reciprocating tilt cycle of a wiper arm is adjusted according to heavy rain and light rain to switch between a high speed (high) and a low speed (low) has been put into practical use. Also,
Instead of two-stage switching between high speed and low speed, three
Wiper devices having a structure that can be adjusted in steps are also in practical use.

[0003]

In a wiper device for changing the reciprocating tilt cycle of the wiper arm, there is a problem that the inertial energy of the wiper arm changes with the cycle change. FIGS. 4A and 4B are explanatory diagrams of a problem associated with a change in the reciprocating tilt cycle of the wiper arm. FIG. 4A illustrates a state in which the cycle time is short (high-speed operation state), and FIG. 4B illustrates a state in which the cycle time is long. (Low-speed operation state). A window glass 1 is attached to a window glass frame, and a wiper blade (not shown) wipes a substantially fan-shaped area of the window glass surface. Figure 4
Shows a state in which two sets of wiper devices are provided corresponding to one of the window glasses 1. The wiping area is set so that the entire surface of the window glass 1 can be wiped as much as possible by two of the substantially fan-shaped wiping areas (indicated by phantom lines). However, there are technical difficulties described below. That is, if the reciprocating tilt angle (for example, the angle φ) is set relatively large, the tilt angle (φ) is enlarged because the inertia is large at the time of high-speed operation but good at the time of low-speed operation. As described above, the wiping areas 3, 3 'interfere with the window glass frame 2. Specifically, a wiper blade (not shown) collides with the window glass frame 2, and this is repeated. If the reciprocating tilt angle is set relatively small to avoid such a collision, a gap is generated between the wiping areas 4, 4 'and the window glass frame 2 as shown in FIG. The view becomes narrow. In order to solve such a problem, a technique of switching the reciprocating tilt angle of the wiper arm between two stages of wide and narrow by using a two-speed motor whose rotation speed changes between forward rotation and reverse rotation is disclosed in Japanese Patent Application Laid-Open No. 55-2.
No. 5638, "Wiper device". But,
In the above-mentioned known art, (a) the wiper wiping angle adjustment is limited to two steps, wide and narrow, and switching of three or more steps cannot be performed.
As shown in FIG. 3 of the above publication, a load is always applied to the base of the arm (the portion corresponding to the projection 10a), causing breakage. (C) When a plurality of wiper arms are provided, the reciprocating tilt of each wiper arm It is difficult to adjust each corner independently.

[0004] There is a problem.

The present invention has been made in view of the above circumstances, and (a) does not generate a local load that may cause damage; and (b) provides a plurality of wiper arms.
It is easy to independently adjust the wiping area of each wiper arm, (c) three or more steps can be switched, and (d) an adjustment mechanism that automatically changes the wiping area according to the wiper operating speed. The purpose is to provide.

[0006]

The basic principle of the automatic adjusting mechanism according to the present invention created to achieve the above object is as follows. An auxiliary weight is attached to a wiper arm, and the operation cycle time of the wiper arm is adjusted. The auxiliary weight is moved so as to decrease the moment of inertia when the cycle time is short, and to increase the moment of inertia when the cycle time is long. As a specific configuration based on the above principle, the automatic inertia adjustment mechanism according to the present invention includes a wiper arm having a structure in which a wiper arm that reciprocates and tilts around a wiper axis and a reciprocating tilt cycle of the wiper arm is adjusted. The weight is guided so that it can move in the longitudinal direction of the
When the reciprocating tilt cycle time of the wiper arm is short, the weight is moved in a direction approaching the wiper shaft, and when the cycle time is long, the weight is separated from the wiper shaft. And

[0007]

According to the above construction, when the reciprocating tilt cycle time of the wiper arm is short (during high-speed operation), the weight is moved in the direction approaching the wiper shaft (that is, at the root side of the wiper arm), and the wiper arm is moved. Since the surrounding moment of inertia is reduced, the inertia force of the wiper arm does not become excessively high at the time of high-speed operation, and there is no possibility that the wiping area will interfere with the window glass frame. Further, when the reciprocating tilt cycle time of the wiper arm is long (during low-speed operation), the weight is moved in a direction away from the wiper shaft (that is, the tip side of the wiper arm), and the moment of inertia of the wiper arm around the wiper axis increases. In addition, when the low-speed operation is performed, the inertia force of the wiper arm does not become too small, and there is no possibility that the wiping area does not reach the window glass frame. In addition, since the weight is moved in the length direction of the wiper arm, it can be adjusted not only in three or more steps but also steplessly by changing the moving distance and stopping at an arbitrary position. is there. Since the weight is moved as described above, the weight can be adjusted easily and quickly without replacing mechanical components, and even when a plurality of wiper arms are provided, each of the wiper arms can be individually adjusted. Can be adjusted independently. In addition, since no other changes are made to the mechanical transmission system, there is no danger of locally generating excessive stress, which may cause breakage of the wiper arm and wear of the contact portion. As there is no operation, operation reliability is high and durability is excellent.

[0008]

Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a perspective view of a wiper arm to which an embodiment of an automatic inertia moment adjusting device configured by applying the automatic inertia adjusting mechanism of the wiper device according to the present invention, and a supporting and driving portion thereof. The wiper arm 7 is rotatably supported by the pivot shaft 6 with respect to the wiper head 5. The wiper head 5 is fixed to a wiper shaft (represented by a center line) 8. The wiper shaft 8 is reciprocally rotated as shown by a reciprocating arc arrow θ.
A wiper blade (not shown) is connected to the wiper arm tip 7a.
Attached to. The wiper arm 7 is urged by a coil spring 9 in a direction to press the wiper blade against a window glass (both not shown).
The automatic moment of inertia adjusting device 10 according to the present invention is fixed to the wiper arm 7 by a mounting screw 10a.
An electric wire 10b connects the automatic moment of inertia adjusting device 10 to an operation panel in a driver's seat. For convenience of explanation, the illustration XX 'is referred to as the longitudinal direction of the wiper arm. FIG. 1 is an exploded perspective view of an automatic inertia moment adjusting device which is an embodiment of an automatic inertia moment adjusting mechanism according to the present invention. Reference numeral 10c denotes a box constituting a housing of the apparatus according to the present embodiment, and 10d denotes a lid. The feed screw 10f rotated by the motor 10e is provided therein so as to be parallel to the longitudinal direction XX 'of the wiper arm. The moving weight 10g is provided with a female screw 10h that is screwed with the feed screw, and a slide contact 10i that opens and closes an energizing circuit of the motor 10e is fixed to the moving weight 10g. The feed screw 10f is a motor 10e.
As a result, the moving weight 10g is moved forward and backward in the longitudinal direction XX 'of the wiper arm by the screw feed action. When the moving weight 10g moves forward and backward, the sliding contact 10i fixed to the moving weight slides on the printed circuit board 10j. For convenience of description, when the moving weight 10g is moved toward the tip of the wiper arm by rotation of the motor 10e, the rotation direction of the motor is referred to as forward rotation. When it is moved toward the root of the wiper arm, it is called reverse. When the reciprocating tilt of the wiper arm is switched at a high speed, the motor 10e is reversely rotated as described later with reference to FIG. 3, and moves the moving weight 10g in the root direction of the wiper arm (the direction of arrow X). This reduces the moment of inertia of the wiper arm, and the wiping area of the wiper blade tends to shrink,
Excessive wiping area during high-speed operation is prevented. When the reciprocating tilt of the wiper arm is switched to low speed, the motor 1
0e is rotated forward as described later with reference to FIG. 3, and moves the moving weight 10g in the direction of the tip of the wiper arm (the direction of the arrow X '). As a result, the moment of inertia of the wiper arm increases, and the wiping area of the wiper blade tends to expand, thereby preventing the wiping area from becoming too small during low-speed operation. The operation speed of the wiper arm is switched between high, medium, and low. When the speed is switched to the medium speed, the moving weight 10g is moved to the vicinity of the center in the longitudinal direction of the wiper arm as described later with reference to FIG. Therefore, the magnitude of the moment of inertia is an intermediate value between high speed and low speed. FIGS. 3A and 3B are views for explaining means for controlling the rotation of the motor in the embodiment according to the present invention, wherein FIG. 3A is an electric system diagram, and FIG. It is a drawn chart. 10j shown in FIG.
Is a printed circuit board 10j described above with reference to FIG. 1, on which fixed contact plates A, B, and C formed of three conductive patterns parallel to the longitudinal direction of the wiper arm are formed. 3 is a slide contact 10i described above with reference to FIG. 1, and is fixed to the moving weight 10g, and is moved together with the moving weight in the longitudinal direction of the wiper blade. Touch A, B, C,
Separate and switch electrical circuits. When the motor 10e stops for a predetermined time or longer, the switch S is turned off.
When the low-speed switches H, M, and L are switched, the switch S is turned on. When the moving weight 10g and the slide contact 10i are located near the root side (right side in the figure) of the wiper arm as shown, the fixed contact plates A and B are electrically connected. Further, when it is located near the tip end side (left side in the figure) of the wiper arm, the fixed contact plates A and C are electrically connected. And, when located near the center of the wiper arm, the fixed contact plates A, B, and C are electrically connected to each other. As a result, as shown in the bottom column of the chart shown in FIG.
In the low speed state, the motor 10e rotates forward and the moving weight 10
g is moved to the tip side (to the left in the figure). Accordingly, the slide contact 10i also moves to the distal end side (leftward), and when it comes off beyond the left ends of the fixed contact plates A and C, the moving weight 10g is located at the stroke end on the distal end side in the longitudinal direction of the wiper arm. Stop. Similarly, FIG.
As shown in the lowermost column of the table shown in FIG. 7, in a high-speed state, the motor 10e rotates in the reverse direction, and the moving weight 10g is moved to the root side (rightward in the figure). Accordingly, the slide contact 10i also moves to the root side (rightward), and when it comes off beyond the right ends of the fixed contact plates A and B, the moving weight 10g.
Stops at the end of the stroke at the root side in the longitudinal direction of the wiper arm.

[0009]

According to the present invention, when the reciprocating tilt cycle time of the wiper arm is short (during high-speed operation), the weight is moved in the direction approaching the wiper shaft (that is, the root side of the wiper arm), and the wiper arm is moved. Since the moment of inertia around the wiper axis is reduced, the inertia force of the wiper arm does not become excessive at high-speed operation, and there is no possibility that the wiping area will interfere with the window glass frame. Also,
When the reciprocating tilt cycle time of the wiper arm is long (during low-speed operation), the weight is moved in a direction away from the wiper shaft (that is, the tip side of the wiper arm), and the moment of inertia of the wiper arm around the wiper axis increases. Then, the inertia force of the wiper arm does not become too small, and there is no possibility that the wiping area does not reach the window glass frame. In addition, since the weight is moved in the length direction of the wiper arm, it can be adjusted not only in three or more steps but also steplessly by changing the moving distance and stopping at an arbitrary position. is there. And
Since the weight is moved as described above,
Adjustment can be performed easily and quickly without replacing mechanical components, and even when a plurality of wiper arms are provided, each wiper arm can be adjusted independently. In addition, since no other changes are made to the mechanical transmission system, there is no danger of locally generating excessive stress, which may cause breakage of the wiper arm and wear of the contact portion. Therefore, there is an excellent practical effect that the operation reliability is high and the durability is excellent.

[Brief description of the drawings]

FIG. 1 shows an automatic moment of inertia adjusting mechanism according to the present invention.
It is an exploded perspective view of an automatic moment of inertia adjustment device which is an example.

FIG. 2 is a perspective view of a wiper arm on which an embodiment of an automatic inertia moment adjusting device configured by applying the automatic inertia adjusting mechanism of the wiper device according to the present invention, and a supporting and driving portion thereof.

FIG. 3 is a view for explaining means for controlling rotation of a motor in the embodiment according to the present invention,
(A) is an electrical system diagram, and (B) is a chart depicting an open / closed state of an electric circuit.

4A and 4B are explanatory diagrams of a problem associated with a change in the reciprocating tilt cycle of the wiper arm, wherein FIG. 4A illustrates a state in which the cycle time is short (high-speed operation state), and FIG. The state (low-speed operation state) is depicted.

[Explanation of symbols]

1 ... window glass, 2 ... window is a lath frame, 3, 3 '
... Excessive wiping area, 4,4 '... Extra small wiping area, 5
... Wiper head, 6 ... pivot, 7 ... Wiper arm, 7a
... tip end of wiper arm, 8 ... wiper shaft, 9 ... coil spring, 10 ... automatic adjustment device for moment of inertia, 10a ...
Mounting screws, 10b ... wires, 10c ... boxes, 10d ...
Lid, 10e motor, 10f feed screw, 10g moving weight, 10h female screw, 10i slide contact, 1
0j: Printed circuit board.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akira Toyama 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Motor Co., Ltd. (56) References JP-A-4-24148 (JP, A) JP-A-57- 15045 (JP, A) JP-A-57-95235 (JP, A) JP-A-57-95237 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60S 1/08 B60S 1 / 18 B60S 1/32

Claims (1)

(57) [Claims] 1. A wiper device having a wiper arm that reciprocates and tilts around a wiper shaft, wherein a reciprocating tilt cycle of the wiper arm is adjusted, wherein a weight is guided so as to be movable in a longitudinal direction of the wiper arm. When the reciprocating tilt cycle time of the wiper arm is short, the weight is moved in a direction approaching the wiper shaft, and when the cycle time is long, the weight is separated from the wiper shaft. An automatic inertia adjustment mechanism for a wiper device.