JPH0723082B2 - Wiper device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

A Industrial Field B Conventional Technology C Problems to be Solved by the Invention D Means for Solving Problems E Action F Example G Effect of Invention [A Industrial Field] The present invention is, for example, an automobile. The present invention relates to a wiper device for wiping a glass window of a vehicle such as.

[B Conventional Technology]

In this type of wiper device, the swing motion of the crank shaft, which is the output shaft of the wiper motor unit, is converted into reciprocating rotary (angular) motion by the link mechanism, and as shown in FIG.
The wiper blade WB is adapted to perform a reciprocating wiping motion over an angle α between points A and B.

[C Problems to be Solved by the Invention]

Referring to FIG. 14, the angle θ formed by the normal line of the window glass 10b and the center line of the wiper blade WB is defined as the error angle (Erro
r Angle). This is because the windshield of a vehicle, especially a vehicle, usually has a three-dimensional curved surface shape, and as shown in (a) and (b) of Fig. 14, the wiping position (the position of the wiper blade). ) Changes. In the text, the error angle θ is called positive (+) when the blade apex is tilted in the same direction as the advancing direction 10d of the wiper blade WB, and negative (-) when it is opposite.

The error angle θ changes as shown in FIG. 15 when the wiper blade WB makes a reciprocating wiping motion between points A and B in FIG. That is, when the error angle θ = 0, the wiper blade WB and the windshield 10b become a right angle, and the error angle θ becomes positive in the first half and negative in the latter half between the wiping forward strokes (point B → point A). On the contrary, in the wiping return stroke (between points A and B), the error angle θ becomes negative in the first half and becomes positive in the latter half. 16th
The figure shows the direction of the air flow 10e on the windshield 10b. The wiper blade WB is used during the forward wipe process (point B → point A).
The direction of the wiping direction 10d and the direction of the airflow 10e coincide with each other, and conversely, in the wiping return stroke (point A → point B), the both directions are opposite. FIG. 17 is a diagram showing the wind speed distribution on the windshield 10b by the ratio υ / V of the wind speed υ to the vehicle speed V. In the wiping forward stroke (point B → point A) in the latter half thereof, and the wiping return stroke (A). Point → B
Point), the influence of the airflow 10e becomes larger in the first half of the above, that is, at the position where the error angle becomes negative.

(1), (2) and (3) in (a) of FIG. 18 show the theoretical relationship between the wiper blade WB and the front glass 10b with respect to the change of the error angle θ in the wiping forward stroke (point B → point A). As shown in the figure, the error angle θ has three cases of zero, positive, and negative [(1), (2), and (3)] depending on the position of the wiper blade. However,
In the experiment conducted by the inventors, in reality, in the case of the wiping forward stroke (point B → point A), the results are shown in (1), (2) and (3) of (b) of FIG. As shown, the wiping portion 10c of the wiper blade is pushed and bent in the wiping direction 10d by the air flow 10e, and in the case of the wiping return stroke (point A → point B), the wiping portion 10c is wiped.
It was revealed that c was pushed and bent in the direction opposite to the wiping direction 10d (not shown), and inversion defects occurred in the cases (1) and (3) of (b) in FIG. That is, in the latter half of the wiping forward stroke (point B → point A), the error angle θ of the wiper blade WB changes from positive to negative, and the stronger wind pressure of the airflow 10e causes the wiping portion of the wiper blade WB. 10c is pushed and bent in the wiping direction 10d, and as a result, the direction of the wiping portion 10c and the wiping direction 10d match, resulting in defective reversal, a chattering phenomenon appears, and an unwiped region occurs on the front window 10b. Therefore, as shown in FIG. 19, the wiping property becomes worse as the vehicle speed increases in a region where the vehicle speed exceeds a certain value, and the forward visibility is significantly deteriorated, which is a serious problem. As described above, the inversion defect occurs in the latter half of the wiping forward stroke. In the first half of the wiping process, the error angle θ
Is positive, the wiping portion 10c is not completely pushed and bent at the vehicle speed at which the reversal failure occurs in the latter half of the wiping forward stroke, as shown in (2) of (b) of FIG. . Also, in the wiping return stroke, the arrows of the wiping direction 10d in (1), (2) and (3) of (b) in FIG. 18 are in the opposite direction, but in this return stroke, the wiping is performed by the wind pressure of the air flow 10e. Since the portion 10c is pushed and bent in the direction opposite to the wiping direction 10d, the inversion failure does not occur. The reversal failure occurs in the latter half of the wiping forward stroke. At this time, the error angle θ is negative, and the absolute value of the error angle becomes even larger because the wind pressure of the airflow 10e is added to this, resulting in reversal failure.

Therefore, it is an object of the present invention to provide a wiper device that prevents the occurrence of the above-mentioned inversion failure.

[D means for solving problems]

The present invention relates to a wiper device adapted to convert a turning motion of a crankshaft of a wiper motor unit into a reciprocating rotary motion by a link mechanism to cause a wiper blade to perform a reciprocating wiping motion. An error angle variable mechanism is provided in the error angle variable mechanism, and the error angle variable mechanism is tiltable with respect to the axis of the rotation shaft by a rotation shaft having one end connected to the link mechanism and a connection pin at the other end of the rotation shaft. Also, for tilting the variable angle rotary shaft with respect to the axis line of the variable angle rotary shaft, one end of which is connected to the rotary shaft so that the rotational force of the rotary shaft can be transmitted and the other end of which is connected to the wiper arm. The angle varying device is provided with the angle varying device with respect to the axis of the rotating shaft only in the forward process of wiping the wiper blade. It is configured to act near one end of the variable angle rotation shaft so as to incline the shaft by a predetermined angle, and the size of this predetermined angle is such that the error angle of the wiper blade does not become negative at the end of the wiping forward stroke. It is characterized by being large.

[E action]

An increase is added to the error angle of the wiper blade connected to the variable angle rotary shaft during the wiping forward stroke. The amount of this increase is the end of the wiping stroke (A
Point) is an angle that prevents the error angle θ of the wiper blade from becoming a negative value. Therefore, since the error angle θ does not become negative even in the latter half of the wiping forward stroke, the occurrence of inversion failure is prevented.

[F Example]

FIG. 1A is an exploded view of each part of an automobile front wiper device embodying the present invention, in which a crankshaft CS of a known wiper motor unit WM has an error angle variable via a known wiper link WL and a link arm LA. It is transmitted to the input part of the mechanism 1, and its output part is fixed to the base end of the wiper arm WA by the arm nut 1m. The tip of the wiper arm WA has a well-known wiper blade W having a blade rubber 10a.
It is connected to B.

Referring to FIG. 1, the error angle variable mechanism 1 has a hollow housing 1j formed by screwing two upper and lower generally cup-shaped parts together. There is a shaft hole in the bottom wall of the housing 1j, and in this shaft hole, a rotary shaft 1a whose lower end is fixed to the link arm LA by a link nut 1n is rotatably mounted via a bearing 1g, and an error angle is set. The input unit of the variable mechanism 1 is configured. housing
The top wall of 1j is inclined with respect to the axis of the rotating shaft 1a, and is fixed to the cowl 10 of the vehicle body by a mounting screw 1p. A spacer 1h is interposed between the link arm LA and the bearing 1g. The top wall of the housing 1j and the cowl 10 of the vehicle body have openings aligned with each other, and the variable angle rotary shaft 1b whose upper end is fixed to the wiper arm WA by the arm nut 1m is swingably and loosely fitted in the opening. The gap between the rotary shaft 1b and the cowl 10 of the vehicle body is sealed by a flexible dust-made grommet 1K. The lower end portion 1b 'of the variable angle rotary shaft 1b is formed with a recess 1r having a larger diameter than the rotary shaft 1a and facing downward, and the upper end of the rotary shaft 1a is loosely fitted in the recess 1r. The connecting pin 1c is the lower end 1b ′ of the variable angle rotary shaft 1b.
Can be swung with respect to the upper end of the rotating shaft 1a (that is, each movement is free)
Connected to. As a result, the variable angle rotary shaft 1b constitutes the output section of the error angle variable mechanism, and the power of the wiper motor unit WM is transmitted to the wiper arm WA. In this case, the error angle variable mechanism 1 acts not only to make the wiper arm WA and the wiper blade WB make a reciprocating angular motion about the axis of the rotary shaft 1a but also to make an angular motion about the axis of the connecting pin 1c. The structure that causes this action will be described below.

On the lower end surface of the variable angle rotary shaft 1b (bottom surface of the lower end portion 1b '),
As shown in FIG. 2, two diametrically opposed protrusions 2a, 2b having the same height are provided in a protruding manner. One protrusion 2a is continuous with the outer peripheral surface of the lower end 1b ', and the other protrusion 2b is the lower end.
It is continuous with the inner peripheral surface of 1b ', and therefore the distance of the lower end portion 1b' from the axis is larger in the protrusion 2a. These protrusions 2
As is clear from (a) and (b) of FIG. 5, a and 2b are wedge-shaped with a knife edge at the tip.

In the housing 1j, an annular angle variable plate that constitutes a main part of the angle variable device in a state of being in contact with the protrusions 2a and 2b.
1d is arranged around the rotating shaft 1a. An annular flange portion of the bearing 1g is interposed between the variable angle plate 1d and the bottom wall of the housing 1j. A cylindrical rotary stopper 1e is provided in the housing 1j and is pressed by the compression coil spring 1f toward the variable angle plate 1d. Rotating stopper
1e is for preventing the variable angle plate 1d from reversing, and for this purpose, as shown in FIG. 2B, a plurality of guide projections 2i are provided on the outer peripheral portion at equal intervals in the circumferential direction. And is axially slidably engaged with the axial guide groove 1q on the inner peripheral surface of the housing 1j, and the stopper projection 2h is provided on the bottom surface.
Are provided at equal intervals in the circumferential direction. Each stopper projection 2h has a wedge shape having a knife edge at its tip, as shown in FIG.

The surface of the variable angle plate 1d opposite to the bearing 1g is 2A
As clearly shown in the figure, the outer peripheral portion 2k, the central portion 2j and the inner peripheral portion 2l
The outer projection 2k of the stopper 1e is pressed against the outer circumference 2k, and the projections 2a and 2b provided on the bottom surface of the variable angle rotary shaft 1b are respectively attached to the central portion 2j and the inner circumference 2l. It is pressed (see Fig. 1). The outer peripheral portion 2k is composed of a groove portion 2g in the radial direction and a mountain portion 2y between these groove portions, and the groove portions 2g have the same number as the stopper projections 2h and are provided at equal intervals in the circumferential direction. As shown in (c) of FIG. 3, each groove 2g has a cross-sectional shape (cross section cut along a plane in the circumferential direction) and a size that substantially tightly engages the stopper projection 2h, and has a mountain portion. The surface of 2y lies in a plane perpendicular to the axis of the rotating shaft 1a. Each groove 2g has a V-shaped side surface, and one side surface is parallel to the axis of the rotating shaft 1a (hereinafter referred to as "vertical side surface"), but the other side surface is inclined with respect to the axis ( As shown in FIG. 3C, when the stopper projection 2h is engaged with the groove 2g, as can be seen from FIG. 3C, (4), the angle variable plate 1d is moved in the direction shown by the arrow 5l. When a rotating force is applied, the inclined side surface of the groove 2g is stopped by the cam action.
2h is pushed up in the direction of arrow 5k, whereby the rotary stopper 1e is pushed upward in the axial direction against the spring 1f, so that the variable angle plate 1d can rotate in the direction of arrow 5l. However, even if the angle variable plate 1d is given a rotational force in the direction opposite to the arrow 5l, the stopper projection 2h and the groove
The rotation of the variable angle plate 1d is prevented by the engagement with the vertical side surface of 2g.

The central portion 2j of the variable angle plate 1d is, as shown in FIG. 2A, a plurality of groove portions 2c arranged at equal intervals in the circumferential direction, which are engageable with the protrusions 2a on the bottom surface of the variable angle rotation shaft 1b, It is composed of a mountain portion 2d between these groove portions. The mountain portion 2d is inclined so as to be lower inward in the radial direction, and the angle of this inclination is equal to the inclination angle β of the variable angle rotary shaft 1b during operation, which will be described later.
As shown in (a) of FIG. 3, the groove portion 2c has a cross-sectional shape and a size to receive the protrusion 2a almost tightly, and the groove portion 2c
One side surface is parallel to the axis of the rotating shaft 1a (hereinafter referred to as “vertical side surface”), but the other side surface is inclined with respect to the axis.

As shown in FIG. 2A, the inner peripheral portion 2l of the variable angle plate 1d has a plurality of peaks 2n at the same height level as the bottom of the groove 2c of the central portion 2j and a plurality of valleys lower than these peaks. The peak portion 2n and the valley portion 2m are radially aligned with the peak portion 2d and the groove portion 2c of the central portion 2j, respectively (see (a) in FIG. 2A). Both the surface of the peak 2n and the bottom of the valley 2m are flat (see (b) in FIG. 3).

The number of the groove portions 2c of the central portion 2j is set so that the angle α between two adjacent groove portions 2c is equal to the wiping angle of the wiper blade WB. When the variable angle rotary shaft 1b is rotated by the rotation of the rotary shaft 1a, the protrusion 2a enters the groove 2c, and then the peak 2d.
The operation of riding on the vehicle and then entering the groove 2c is sequentially repeated to rotate (see (1) to (5) in (a) of FIG. 3). At the same time, the protrusion 2b rides on the mountain portion 2n and then the valley portion.
The operation of entering 2 m and then riding on the mountain 2n is sequentially repeated to rotate ((1) to (1) of (b) in FIG. 3).
(See (5)). As described above, the protrusions 2a and 2b have the same height (the same amount of protrusion), and the mountain portion 2n of the inner peripheral portion 2l is the groove portion of the central portion.
Since the valley portion 2m is located at the same height level as the bottom of 2c and the valley portion 2m is lower than the mountain portion 2n, the protrusion 2a has the mountain portion 2d as shown in (2) of FIG.
When the projection 2b is on the upper side and the protrusion 2b is in the valley 2m, the angle variable rotary shaft 1b
Is tilted with respect to the rotation shaft 1a by a tilt β with respect to the connecting pin 1c as shown in FIG. At this time, as described above, the crest 2d is inclined radially inward by β degrees, so that the knife edge at the tip of the protrusion 2a comes into line contact with the surface of the crest 2d instead of point contact. Therefore, the knife edge is less likely to be worn as compared with the case of the point contact. When the projection 2a enters the groove 2c and the projection 2b rides on the ridge 2n, the variable angle rotary shaft 1b is aligned with the rotary shaft as shown in FIG.

Next, the operation will be described.

The turning motion of the crankshaft CS of the wiper motor unit WM is converted into the reciprocating rotary motion of the rotary shaft 1a by the link mechanism consisting of the link WL and the link arm LA, and this motion is transferred via the connecting pin 1c and the variable angle rotary shaft 1b. TE wiper arm WA
And the wiper blade WB is transferred to A as shown in FIG.
With the point as the top dead center and the point B as the bottom dead center, a reciprocating wiping motion is performed between point A and point B on the windshield 10b of the automobile. The angular range of this movement is α degrees as described above. (1), (2), (3) of (a), (b) and (c) of FIG.
(4) and (5) are points B and B in FIG. 6, respectively.
Protrusions 2a, 2b and stopper protrusion 2h when the wiper blade WB is located between points A, A, A-B, and B
And the positional relationship of each part corresponding to them. Further, (1), (2), (3) and (4) in FIG. 5 correspond to (1), (2), (3) and (4) in FIG. 3, respectively.

Now, when the wiper blade WB is at the start of operation or at the point of point B in FIG. 6 during wiping operation, as shown in (1) of (a) of FIG. Since 2a is in the groove 2c of the central portion 2j of the variable angle plate 1d, the variable angle rotary shaft 1b is not inclined and is in the initial zero state ((1) in FIG. 5). At this time, as shown in (1) of (b) of FIG. 3, the protrusion 2b has a valley portion 2m of the inner peripheral portion 2l.
It is floating from the bottom of the
Since 2h is in the groove 2g of the outer peripheral portion 2k of the angle variable plate 1d, the angle variable plate 1d rotates in the reverse direction, that is, in the direction opposite to the arrow 5l in (4) of FIG. Restraining movement. Next, as shown in (2) of FIG.
The rotation of the rotary shaft 1a causes the variable angle rotary shaft 1b to start rotating, and at the same time, the protrusion 2a starts to rotate in the direction of arrow 5b while rising in the direction of arrow 5a along the inclined side surface of the groove 2c, and at the same time, the protrusion 2b It descends toward the valley 2m in the direction of the arrow 5f, and as a result, the variable angle rotary shaft 1b tilts with respect to the rotary shaft 1a by the tilt angle θ as shown in (2) of FIG. At the same time, the protrusion 2b is an arrow
Rotate in the 5g direction. At this time, the projection 2h of the stopper 1e is in a state in which the rotation of the angle variable plate 1d is restrained because the stopper 1e is pressed against the variable angle plate 1d by the spring 1f and the guide protrusion 2i is in the guide groove 1q. keep. When the wiper blade WB reaches point A in Fig. 6,
As shown in (3) of FIG. 3, the protrusion 2a descends in the direction of the arrow 5c and is inserted into the groove 2c, and at the same time, the protrusion 2b rises in the direction of the arrow 5h and separates from the valley 2m to allow the variable angle rotary shaft 1b to move. The initial angle is zero ((3) in FIG. 5). At this time, protrusion 2h
Keeps being inserted into the groove 2g. Then the rotation axis
When 1a starts rotating in the opposite direction, as shown in (4) of FIG. 3, the protrusion 2a is inserted into the groove 2c and starts rotating in the directions of arrows 5d and 5e together with the angle varying plate 1d. To do.
At this time, the protrusion 2b is separated from the valley portion 2m by an arrow 5i.
Direction and the valley part 2m also rotates in the direction of arrow 5j. At the same time, the protrusion 2h rises along the inclined side surface of the groove 2g in the direction of the arrow 5k against the spring 1f. That is, rotation of the variable angle plate 1d with respect to the rotary stopper 1e is allowed only in the direction of the arrow 5l and blocked in the opposite direction, and the variable angle rotary shaft 1b is provided between the points A and B in FIG. Keeps the initial angle of zero ((4) in FIG. 5). Next, when the point B is reached again, as shown in (5) of FIG.
2h is lowered by the pressing force of the spring 1f in the direction of the arrow 5m and is inserted into the groove 2g, so that it is in the same state as (1) in FIG.

After all, the variable angle rotary shaft 1b makes one reciprocating rotation and the connecting pin during one reciprocating wiping operation of the wiper blade WB.
The tilting motion is performed once around 1c, the variable angle plate 1d rotates by the wiping angle α, and the stopper 1e moves up and down by 1 time.
It will be done once. Since the tilting motion of the variable angle rotary shaft 1b is transmitted to the wiper blade WB via the wiper arm WA, the error angle θ increases by the angle β in the wiping forward stroke from point B to point A in FIG.

This operation is shown in Fig. 7, and the variable angle rotary shaft 1b increases the error angle θ in the positive direction by β degrees only in the wiping forward stroke (point B → point A), but the wiping return stroke. This increase does not occur at (Point A → Point B). Ie B
Point 8a, Point B → Point A 8b, Point A 8c, Point A → Point 8d,
The error angle θ changes on each line. In the forward stroke of wiping, as shown by the lines 8a and 8b in FIG. 7, the error angle θ is only on the positive side, and the relationship between the blade WB and the windshield 10b is (1) in (a) of FIG. And (2)
Therefore, it is possible to prevent the occurrence of inversion failure.

However, as shown in FIG. 8, if the increment β of the error angle θ is made too large, the wiping property deteriorates. This is because inversion defects occur in the latter half of the wiping return process. That is, in the latter half of the wiping return stroke (point A → point B), the error angle θ is originally positive as described above (Fig. 15), and the positive error angle increment β
Therefore, even if the wiping portion 10c is pushed and bent by the wind pressure of the airflow 10e in the direction opposite to the wiping direction, the wiping portion 10c is not completely pushed and bent to the place where the inversion failure does not occur, resulting in the wiping portion 10c.
Since the direction of and the wiping direction remain the same, inversion failure occurs. Therefore, in the embodiment of the present invention, the error angle increment β is set so that the error angle θ becomes 0 (zero) at the end point (that is, point A) of the forward stroke of the wiper blade. The specific value of the angle β is determined by matching the vehicle and the wiper device.

As described above, by increasing the error angle of the wiper blade only in the forward stroke of the wiper blade, it is possible to improve the reversal failure during restrained running in the rain, and as a result, the upper limit of the vehicle speed at which the reversal failure does not occur. It is clear from the comparison between FIG. 9 (in the case of the above-mentioned embodiment) and FIG. 19 (in the case of the conventional case) that Δ can be increased by ΔV.

10 and 11 show a second embodiment of the present invention, in which the same parts as in the first embodiment are designated by the same reference numerals. Only the differences will be described below.

Angle variable plate 11d that constitutes the main part of the angle variable device
Is a cup-shaped member, and has a bottom wall 11d-1 and an annular upper plate portion 11e provided at the upper edge of the peripheral wall. The inner surface (upper surface) of the bottom wall 11d-1 is provided with the same central portion 2j and inner peripheral portion 2l as in the first embodiment.
2A and 3 have the same ridges and grooves as those shown in FIGS. 2A and 3, and the inner peripheral portion 2l also has ridges and valleys. Similarly to the first embodiment, projections 2a and 2b are also provided on the bottom surface of the variable angle rotary shaft 1b, and the central portion 2j of the bottom wall 11d-1 of the variable angle plate 11d and the mountain portion of the inner peripheral portion 2l, As in the case of the first embodiment, the groove and the valley cooperate with each other. The upper plate portion 11e of the variable angle plate 11d includes a downward flat surface 11e ′ engageable with an annular upward shoulder 1b ″ provided on the outer peripheral surface of the lower end portion 1b ′ of the variable angle rotary shaft 1b, and an inner peripheral surface of the housing 1j. Vertical groove 1 formed on the surface
and a guide projection 12i slidably engaged with q.
A downward pressing force is constantly applied to the upper surface of the upper plate portion 11e by the compression coil spring 1f. A solenoid coil 16f is provided in the housing 1j around the coil spring 1f. This solenoid coil 16f operates by the electric circuit shown in FIG.

The operation of the second embodiment is basically the same as that of the first embodiment, and is as follows. In the forward stroke of wiper wiping, when the solenoid coil 16f is energized at the start of wiping, the variable angle plate 11d resists the pressing force of the spring 16g.
Are sucked upwards and the central portion 2j and the inner peripheral portion 2 of the bottom wall 11d-1 are
l contacts the protrusions 2a and 2b of the variable angle rotation shaft 1b, respectively. The operation thereafter is similar to that of the first embodiment, and the protrusions 2a and 2b are respectively formed in the central portion 2j and the inner peripheral portion 2l.
When the wiper blade is in the forward stroke, the variable angle rotary shaft 1b tilts by the tilt angle β to perform the rotary motion. In the wiping-back process, the solenoid coil 16f is de-energized, and the spring 1f pushes the upper plate 11e downward until the downward plane 11e 'of the upper plate 11e contacts the shoulder 1b "of the variable angle rotary shaft 1b. Therefore, in the wiping return stroke, the variable angle rotary shaft 1b returns to the initial position, and the increase β of the error angle is eliminated.With this configuration, the error angle can be adjusted only by controlling the energization of the solenoid coil 16f. Since it is possible to freely select the case where the additional β is added to θ,
By providing the control circuit 17 as shown in FIG. 7, it is possible to more effectively take measures against the inversion defect. The control circuit 17 includes a relay coil 17b, a relay switch 17c, and a signal comparison unit 17h. The power supply 17a and the solenoid coil 16f are connected to the control circuit 17 as illustrated. The input signals are the wiper switch 17e, vehicle speed sensor 17d, and wiper link WL.
It is provided by limit switches 17f and 17g provided at both ends of. Limit switches 17f and 17g, wipe the wiper,
It is attached to the position corresponding to the bottom dead center (points A and B), the wiper switch 17e is ON, the vehicle speed sensor 17d is ON at the set vehicle speed or higher, the wiper link WL is at the bottom dead center, and the limit switch 17f is ON. Is energized, the relay switch 17c is closed, the solenoid coil 16f is energized, and the variable angle rotating shaft 1b is inclined by β degrees, and the increment β is added to the error angle θ. The wiper is at top dead center (A
Point), the limit switch 17g is turned on, the relay coil 17b is de-energized, the variable angle rotary shaft 1b is not tilted, and the error angle θ returns to the initial angle. By repeating this, in the process of wiping the wiper,
The increment β is added to the error angle θ only when the vehicle speed is equal to or higher than the set vehicle speed.

Also in the third embodiment shown in FIG. 12, the rotary shaft 1a and the variable angle rotary shaft 1b are provided.
And a connecting pin 1c for connecting them. The variable angle mechanism changes the error angle by tilting the variable angle rotary shaft 1b by pushing the lower end 1b 'of the variable angle rotary shaft 1b by a piston 18d provided in a cylinder 18e formed in the housing 1j. One piston 18d and one cylinder 18e are provided on the left and right sides of the variable angle rotary shaft 1b to form the main part of the variable angle device. The piston 18d and the cylinder 18e tilt to the left or right depending on the direction of the working fluid (water, air, oil, etc.) You can change the corners. In the illustrated embodiment, in the wiper wiping stroke, the working fluid is pumped into the left cylinder 18e through the line 18g, whereby the left piston 18d compresses the spring 18h and moves to the right as indicated by the arrow. , The lower end portion 1b 'of the variable angle rotary shaft 1b is pushed to tilt the variable angle rotary shaft 1b as shown by an arrow 18i. In the wiper wiping return stroke, on the contrary, the working fluid may be applied to the right piston 18d. A control device for controlling the flow direction of the working fluid is shown in FIG. The control circuit 19 controls the position of the wiper link WL (top dead center,
The input signals from the micro switches 19a, 19b, the wiper switch 19c and the vehicle speed sensor 19d that detect (bottom dead center) are compared and operated to operate the pump 19e and control the direction switching valve 19f to switch the direction of the working fluid. . A check valve 19h is provided between the on-circuit pump 19e and the tank 19g so that the pressure in the connected cylinder 18e does not exceed a certain pressure value.

Although the example in which the present invention is applied to the wiper device for an automobile has been described above, it is obvious to those skilled in the art that the present invention can be applied to the wiper device for other vehicles.

[Effect of Invention]

In the wiper device of the present invention, since the increased amount β is forcibly added to the error angle θ only in the forward stroke of the wiping operation of the wiper blade, the influence of the wind on the blade rubber is reduced. Therefore, conventionally, the occurrence of chatter due to defective reversal of the wiper blade and the deterioration of the wiping property (occurrence of unwiping), which has been caused by the blade rubber being pushed and bent by the wind pressure during high-speed traveling, are improved,
As a result, the upper limit of the vehicle speed range in which the wiper blade inversion failure does not occur is raised to the higher speed side, and the safety of high speed running in the rain is enhanced. Moreover, since the error angle variable mechanism for forcibly tilting the wiper blade has a configuration in which the angle variable rotary shaft connected to the wiper arm is tilted with respect to the rotary shaft that is the input unit during the rotation, Simple structure, reliable operation, and
Easy maintenance and inspection. Further, since the error angle variable mechanism only needs to replace the conventional wiper arm attachment portion, it is not necessary to remake the entire wiper device, and the conventional parts can be used as they are.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of a wiper device of the present invention, FIG. 1A is a perspective view showing an exploded view of the entire wiper device, and (a) and (b) of FIG. A bottom view of the shaft and a vertical cross-sectional view of the lower end portion of the shaft, (A) of FIG. 2A is a top view of the variable angle plate, and (B) and (C) are B-B cross-sections of (A) of FIG. 2A. Fig. And C-C sectional view, (A) and (B) of Fig. 2B are a top view and a longitudinal sectional view of the rotary stopper, and (A) and (B) of Fig. 3 are the lower end portion of the variable angle rotary shaft. The figure which showed the change of the relation with the variable angle plate diagrammatically,
(C) is a diagram schematically showing a change in the relationship between the rotary stopper and the variable angle plate, FIG. 4 is a sectional view showing a state in which the variable angle rotary shaft 1b is inclined with respect to the rotary shaft 1a, and FIG. 5 is FIG. 6 is an enlarged sectional view of an essential part showing a change in the position of the variable angle rotary shaft 1b with respect to the rotary shaft 1a and the variable angle plate 1d, and FIG. 6 is an explanatory view showing the range of the wiping angular movement of the wiper blade on the windshield, FIG. 7 is an explanatory view showing a change of an error angle by the wiper device of the present invention, FIG. 8 is an explanatory view showing a change of a wiping property of the wiper device with respect to an increase of the error angle, and FIG. 9 is a wiping device with respect to a vehicle speed. 10 is a longitudinal sectional view of a second embodiment of the present invention, and FIG. 11 is a solenoid coil 16f shown in FIG. FIG. 12 is an electric circuit diagram for activating the third embodiment of the present invention. FIG. 13 is a longitudinal sectional view of an example, FIG. 13 is a diagram showing an electric circuit and a fluid circuit used in the third embodiment, and FIGS. 14 (a) and 14 (b) are diagrams for explaining a change in error angle. Figure is a diagram showing the change of the error angle with respect to the blade wiping position in the conventional wiper device, Figure 16 shows the relationship between the direction of the air flow on the front glass while the vehicle is running and the wiping movement of the wiper blade Fig. 17, Fig. 17 is an explanatory view showing the wind speed distribution on the windshield, and Fig. 18 (a) shows the theoretical relationship between the wiper blade and the windshield with respect to the change of the error angle in the wiping forward stroke, (b) FIG. 19 is an explanatory diagram showing a realistic relationship revealed by an experiment, and FIG. 19 is a diagram showing a change in wiping property with respect to a change in vehicle speed when a conventional wiper device is used. 1 …… Error angle variable mechanism, 1a …… Rotary axis, 1b …… Angle variable rotary axis, 1c …… Connecting pin, 1j …… Housing, 10 …… Body cowl, WM …… Wiper motor unit CS …… Cam shift, WL …… wiper link, LA …… link arm, WA …… wiper arm, WB …… wiper blade.

Front page continuation (72) Inventor Junaki Ando 1-1 Chome Showa-cho, Kariya city, Aichi prefecture Nihon Denso Co., Ltd. (72) Inventor Hiroshi Takahashi 1-1-chome Showa town, Kariya city, Aichi prefecture NPC (56) References: Actually developed 60-122266 (JP, U)

Claims (1)

[Claims] 1. A wiper device adapted to convert a turning motion of a crankshaft of a wiper motor unit into a reciprocating rotary motion by a link mechanism to cause a wiper blade to perform a reciprocating wiping motion. An error angle variable mechanism is provided between the rotary shaft having one end connected to the link mechanism and the other end of the rotary shaft tiltable with respect to the axis of the rotary shaft by a connecting pin. And an angle variable rotary shaft whose one end is connected so that the rotational force of the rotary shaft can be transmitted and the other end is connected to the wiper arm, and the angle variable rotary shaft is tilted with respect to the axis of the rotary shaft. And an angle changing device for changing the angle with respect to the axis of the rotating shaft only in the forward stroke of wiping of the wiper blade. It is configured to act near the one end of the variable angle rotating shaft so as to incline the rolling shaft by a predetermined angle, and the size of this predetermined angle does not make the error angle of the wiper blade negative at the end of the wiping forward stroke. A wiper device having such a size.