JPH01186449A - Wiper for vehicle - Google Patents

Abstract

PURPOSE:To improve wiping performance by moving the contacting position of a pressure lever to a different position on a cam face through rotation of a cam member thereby modifying tension of a spring member and varying pressure of a wiper blade against a wiping face. CONSTITUTION:A wiper arm 20 comprises a link 22 pivoted to a fixed member 21 and a wiper rod 23 secured to the link 22, and a pressure lever 24 is pivoted coaxially with the link 22. The pressure lever 24 is arranged such that a predetermined contact pressure is applied from the wiper blade against the window through a contact pressure spring 25. A cam plate 37 also servable as a gear plate is fixed rotatably to the lower section of a pivot shaft 26 having upper end secured with the fixing member 21. When the cam plate 37 is rotated through a motor 39, a piston 35 engaged through a pin 36 with an endface cam 37a slides to modify the force of the contact pressure spring 25 through the pressure lever 24.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wiper device for a vehicle, and particularly to a wiper device in which wiper blade pressing pressure is variable.

[Prior art] When a vehicle is running at high speed, a lift force acts on the wiper blade,
Wiper wiping performance deteriorates.

Therefore, various wiper devices have been proposed in which the wiper blade pressing pressure can be changed by directly supporting the arm supporting the wiper blade in a tiltable manner and directly driving the arm in a tilting manner, or by changing the tension of the tension spring. (Special Publication No. 47-20849, Utility Model Publication No. 58-87
654, JP-A-58-93652, JP-A-58-93653, JP-A-62-6853).

[Problems to be Solved by the Present Invention] Incidentally, each of the above-mentioned wiper devices proposed in the past has a problem in that its structure is relatively complicated.

SUMMARY OF THE INVENTION In order to solve this problem, it is an object of the present invention to provide a wiper device for a vehicle that can change the wiper blade pressing force with a simple structure.

[Means for Solving the Problems] The vehicle wiper device of the present invention includes a fixed member that is provided on a pivot shaft that rotates reciprocatingly and rotates integrally with the pivot shaft, and one end of which is pivotally supported by the fixed member to prevent rotation of the fixed member. A wiper arm that is rotatable in a direction perpendicular to the surface and holds a wiper blade at the other end, and a wiper arm that is pivotally supported by the fixed member and is stretched between this and the wiper arm depending on the rotational position. a pressure lever that changes the tension of the spring member; a cam member that is relatively rotatable around the pivot shaft and has a cam surface formed on its peripheral surface and one end of the pressure lever is brought into contact with the cam surface; The cam member is configured to include a rotation drive means for rotating the cam member.

[Operation] In the wiper device according to the claims, when the cam member is rotated by the rotation drive means, the cam member rotates relatively around the pivot axis, and the contact position of the pressure lever moves to a different position on the cam surface. .

As the cam surface it comes into contact with changes, the pressure lever is rotated around the spindle opening, and the tension of the spring member is changed to change the rotation biasing force against the wiper arm, thereby pressing the wiper blade against the wiping surface. Pressure changes.

[First example] Figure 5 shows the device installed on the driver's seat side.

A wiper blade 10, a wiper arm 20, a wiper blade 30, a wiper arm 40, a drive motor 50, and a lever crank link 6 are attached to the lower side of the front window W of the vehicle 1.
0. An arm lowering side mechanism 70 is provided. The broken line indicates the wiping surface of the wiper blade 30.

The apparatus will be explained in detail using FIGS. 1 to 4.

The wiper arm 20 includes a link 22 which is pivotally supported to a fixed member 21 by a shaft 21a and bushes 21b and 21c, and a wiper rod 23 which is fixed to the link 22 by caulking and a rivet 22a.

Further, the wiper blade 10 is attached to the tip of the wiper rod 23.
is attached with screws, etc.

The pressure lever 24 has a shaft 21a, bushes 21b and 21c.
It is pivotally supported coaxially with the link 22. Lever 2
Figure 6 shows the external appearance of 4.

The contact pressure spring 25 has one end suspended in the hole 23a of the wiper rod 23 and the other end suspended in the hole 24a of the lever 24, and is a spring member for generating the necessary contact pressure between the wiper blade 1o and the window W surface. It acts as.

On the other hand, the fixing member 21 of the wiper arm 2o is fixed by a screw 27 to the tip of the pivot shaft 26 which swings through a lever crank link 60 due to the rotation of the drive motor 50.

The pivot shaft 26 is attached to a housing 3o fixed to the vehicle front plate 28 with screws 29, and a washer 31° clip 32 is attached to the housing 3o.
is rotatably supported by the housing 30.

Further, bushings are provided above and below between the housing 3o and the pivot shaft 26, and the space 34 created thereby serves as a lubricating oil reservoir.

The pivot shaft 26 has a hollow structure (FIG. 1), and supports a piston 35 slidably within the hollow hole.

The upper end 35a of the piston 35 is in contact with one end -5 to 24b of the lever 24. Also, a screw 2 is attached to the one end 24b.
4c, and the distance between the one end 24b of the lever 24 and the upper end 35a of the piston 35 can be adjusted by turning the screw 24c. That is, the set arm pressure can be adjusted.

A bottle 36 is integrally provided at the lower end 35b of the piston 35 and is slidable within an elongated hole 26a provided in the pivot shaft 26. As a result, the piston 35 can only move in the axial direction within the pivot shaft 26.

A cam plate 37, which also serves as a gear plate, is attached to the lower part of the pivot shaft 26 so as to be rotatable around the pot shaft (FIG. 2). FIG. 7 shows a perspective view of the cam plate 37. The boss portion of the cam plate 37 has an end cam 3 attached thereto.
7a is formed. Normally, the piston 35 receives the force of the contact pressure spring 25 via the lever 24,
It is always biased to the right in Figure 1. Therefore, the pin 36 is in contact with the end cam 37a of the boss portion of the cam plate 37. Therefore, when the cam plate 37 rotates around the pivot shaft 26, the end cam 37a of the boss portion moves the piston 35.

The end cam 37a has a moving surface 37b for moving the piston 35 and a groove 37 that fits into the pin 36 at the stop position.
It is composed of c. Since the pin 36 and the groove 37c fit together, the cam plate 37 will not rotate around the pivot shaft 26 unless a torque greater than an arbitrary set value is applied.

A notch 37d is provided on the outer periphery of the flange portion of the cam plate 37.
1, 37d-2, 37d-3, and 37d-4 are provided (Fig. 2). The notches 37d-1 to 37d-4 can engage with claws 38 provided near the cam plate 37.

The claw 38 is connected to a small motor 39 fixed to the housing 30.
It is attached to the output shaft 39a of 1 through an elastic body 38a. The claw 38 and the notches 37d-1 to 37d-4 are adapted to engage with each other at any fixed position. For example, in the figure, when the claw 38 continues to rotate clockwise and the swing lever 61 is rotated counterclockwise, the right tip 38b of the claw 38 engages with the notch 37d-1. Then, the cam plate 37 comes to rest, and only the swing lever 61 continues to rotate, and eventually the pin 3
6 slides on the moving surface 37b of the end cam 37a and rises. When the swing lever 61 reaches the inverted position, the pin 36
fits into the groove 37c of the end cam 37a.

When the swing lever 61 starts rotating clockwise, the right tip 38b of the pawl 38 is pushed out of the notch 37d-1 by the outer peripheral end of the cam plate 37, and the pawl end 38b and the notch 37
d-1 is disengaged.

The same relationship as above also occurs with the clawed tips 38b and 37d-2. Also, the left tip of the claw 38c and the notch 37d-3, 37
d-4 has a similar relationship, but the rotation directions are all opposite.

The cam plate 37 has three stop positions with respect to the swing lever 61 due to the claw 38 and the notches 37d-1 to 37d-4.

Here, the load that the pawl 38 receives from the cam plate 37 is
8 and the output shaft 39a of the motor 39, the elastic body 38a bends and is received by the inner wall 30a of the housing 30. Therefore, no excessive load is applied to the output shaft 39a of the motor 39.

Further, the center portion 35c of the piston 35 has tips 35a and 3
The outer diameter is smaller than 5b, and the pivot shaft 2
An oil reservoir 35d is formed inside 6.

With the above configuration, this device operates as follows.

To increase the arm pressure, as shown in Figure 8, let the tension of the spring 25 be P, and the distance between the tension P and the support shaft 21a be H, then rotate the lever 24 clockwise in the figure to increase H. If this is done, the pressurizing torque pxH will increase. in this case,
The cam plate 37 is rotated in a direction to raise the piston 35.

This is done by rotating pawl 38 in the clockwise direction in FIG. To lower the arm pressure, the claw 38 may be rotated counterclockwise to lower the piston 35.

An example of control is shown in FIGS. 9 and 10.

FIG. 9 shows a control block diagram. Signals from a known stop position detection sensor 52 built into the drive motor 50, a wiper switch 53, and a vehicle speed sensor 54 are input to the control circuit 51. Control circuit 51 processes these signals to control drive motor 50 and motor 39.

The control procedure will be explained using the flowchart in FIG. The processing and judgment in each step in the figure are as follows.

5101; Does nothing if wiper (WP> is OFF).

If it is other than OFF, proceed to 5102.

8102, Initialization of each variable, CT1, CT2, CT3
is a variable that counts the number of pulses output when the drive motor 50 reaches the stop position based on the signal from the stop position detection sensor of the drive motor 50, and CT is a low pressure (CT=O), medium pressure (CT
= 2), a variable indicating that high pressure (CT = 3) is set.

5103; If the vehicle speed is Vsan/h or more, proceed to 8126. Otherwise, proceed to 5104.

5104; If WPS/W is not OFF, proceed to S110. If it is OFF, proceed to 5105.

8105-5109. This is a step of setting the pressing pressure to a low pressure. That is, after rotating the motor 39 in the counterclockwise direction, if the motor 50 exceeds the CT rotation stop position, the motor 39 is stopped, and when the motor 50 reaches the stop position, the motor 50 is stopped. This returns the pressure setting from the medium pressure to high pressure setting to the low pressure setting.

5110. If Cr2 is 10, proceed to 8103.

Otherwise (Proceed to Cr2<10>Sl 11).

5ill; CT=2.

5112. If CT2=3, proceed to 5120; otherwise proceed to (CT=O)=Sl 13.

5113 to 5118: This is a step of changing the pressing pressure from low pressure to medium pressure. That is, after rotating the motor 39 clockwise for T1 time, the motor 39 is turned off for 12 hours.
F. After Cr2 increases by 1, the T-time motor 39 is turned ON in the clockwise direction again, and the 12-hour motor 39 is turned OFF. Repeat the above action 10 times. This repetition is to ensure that the claw and cam plate are engaged when the wiper operation is not smooth due to glass freezing, etc., and the number of times is set as appropriate.

5119. CT2=O.

5120-5125: This is a step of changing the pressing pressure from high pressure to medium pressure. That is, after rotating the motor 39 counterclockwise for T1, the motor 39 is turned off for 12 hours.
F. Repeat the above action 10 times. The reason why the motor is temporarily turned off is that if it continues to rotate, the engagement of the claws will shift to the next stage notch.

5L26. If CT2=3, proceed to 8103; otherwise, proceed to 5127.

5127. Let CT=3.

5128 to 5131: This is a step of setting the pressing pressure to high pressure. That is, after rotating the motor 39 clockwise, if the motor 50 exceeds the stop position three times, the motor 3
Stop 9.

8132, CT=O.

With the mechanism, operation, and control content explained above, this device lowers the arm pressure when the wiper is stopped, = 12 - sets the arm pressure to medium when the wiper is operating and the vehicle speed is Vkm/h or less, and when the wiper is operating and the vehicle speed is Vkm/h. /h or more, the arm pressure can be made high.

In the above process, the arm pressure was switched by timer control of the motor 39, but as shown by the broken line in FIG.
It is clear that the cam position can also be controlled by providing a limit S/W or the like on the cam plate 37 or the like.

Further, the control contents for the second embodiment and the subsequent embodiments can be designed using known techniques according to FIG. 10, and therefore will not be particularly explained.

[Second Embodiment] In FIGS. 11 to 13, the pivot shaft 126 is connected to the boss portion 1 of a gear plate 137 that is pivotally supported by a housing 130 that is fixed to the vehicle front plate 128 with screws 129.
37a, and is rotatably supported on the housing 130 by a washer 131 and a clip 132. Further, the boss portion 137a of the gear plate 137 is provided with an oil reservoir 137b, and the pivot shaft 126 is provided with an oil reservoir 126a.

A cam play () 138 shown in FIG. 17 is rotatably mounted around the protrusion 126b of the pivot shaft 126. The cam plate 138, the washer 131, and the boss portion 137a of the gear plate 137 are connected by a pin 139 (FIG. 14) passing through the washer 131, and always rotate together.

An end cam 138a is formed on the cam plate 138. Normally, the lever 124 receives the force of a pressure spring 125, and the rear end 124a of the lever 124 is attached to the screw 1.
The locking tool 141 is made of an elastic body attached by 40.
is pressed against the end face cam 138a via.

The end cam 138a is a moving surface 1 that rotates the lever 124.
38b and the notch 141 of the locking tool 141 in the stop position.
It is constituted by a groove portion 138C that fits into the groove portion a. Therefore, as the cam plate 138 rotates around the pivot shaft 126, the end cam 138a rotates the lever 124.

Furthermore, since the notch 141a and the groove 138c fit together, the cam plate 138 will not rotate around the pivot shaft 126 unless a torque greater than an arbitrary set value is applied.

A notch 137 is provided on the outer periphery of the flange portion of the gear plate 137.
cm1, 137 cm2 are provided (Fig. 15).

The notch 137 cm2 can be engaged with a pawl 142 provided near the gear plate 137.

The pawl 142 is attached to an output shaft 143a of a small motor 143 fixed to the housing 130 via an elastic body 142a.

The claw 142 and the notches 137cm1 and 137cm2 are designed to engage with each other at any fixed position. For example, in the figure, the claw 142 continues to rotate clockwise and the swing lever 1
61 counterclockwise, the left tip 1 of the claw 142
42b meshes with the notch 137cm1. Then, the gear plate 137 comes to rest, and only the swing lever 161 continues to rotate, and eventually the lever 124 moves to the moving surface 1 of the end cam 138a.
It slides on 38b and rotates. When the swing lever 161 reaches the reverse position, the notch 141a (FIG. 16) fits into the groove 138C.

When the swing lever 161 starts rotating counterclockwise, the claw 1
The right tip 142C of 42 is pushed out from the notch 137cm1 by the outer peripheral end of the gear plate 137, and the left tip 14 of the claw
2b and the notch 137cm2 are disengaged. The same relationship as above occurs between the left claw tip 142b and the notch 137cm1, but the rotation direction is opposite here.

Here, since the claw 142 has an elastic body 142a between the claw 142 and the output shaft 143a of the motor 143, the load that the claw 142 receives from the gear plate 137 is received by the inner wall 130a of the housing 130 as the elastic body 142a bends. Therefore, no excessive load is applied to the output shaft 143a of the motor 143.

The operation is similar to that in the first embodiment, but the arm pressure switching in the first embodiment is in three stages, whereas in this embodiment there are two stages.

Also, by adjusting the screw 140, the locking tool 141
is bent to adjust the position of the lever 124. In other words, the set arm pressure can be adjusted.

[Third example] A third embodiment of the invention is shown in FIGS. 18 and 19.

The difference from the second embodiment is that the cam plate 238 and
This is the lever 224. In the second embodiment, the end cam 138C
Whereas the lever 124 was actuated in this embodiment, the present embodiment differs in that it is configured by a cylindrical cam 238a and a pin 224a provided at the rear end of the lever 224. pin 224
a is slidably inserted into the groove 238b of the cylindrical cam 238a, and when the cam plate 238 rotates, the lever 2
24 rotates. Other configurations and operations are the same as in the second embodiment.

[Fourth embodiment] In the first embodiment, the pawl 38 is connected to the motor 3 via the elastic body 38a.
Although it is attached to the output shaft 39a of FIG. 20, the claw 242 may be made of an elastic material (resin, etc.) so that the area around the output shaft 39a is flexible.

Moreover, the same effect can be achieved even if the elastic body 38a is used as a void.

However, in this case, it is necessary to connect the output shaft of the motor 3a and the pawl 38 with a spline or the like.

[Fifth example] A fifth embodiment is shown in FIGS. 21 and 22.

In the second embodiment, the gear plate 137 always rotates together with the pivot shaft 126, and the gear plate 137 is kept stationary only when switching the arm pressure, but in this embodiment, the gear plate 537 is always kept stationary. and rotates the gear plate 537 only when switching.

For this reason, the configuration includes a gear plate 537 rotatably supported around a pivot shaft 526, and a gear plate 53.
7, and a motor 543 that rotates a worm 543a that meshes with a helical gear 537a on the flange portion of the gear plate 537.

The cam plate 538 has a bottom surface 53 on which a locking tool 541 provided at the rear end of the lever 524 slides when the arm pressure is low.
8a, a rear surface 538b that slides when the arm pressure is high, a moving surface 53 that smoothly connects the bottom surface 538a and the rear surface 538b;
An end cam made of 8C is formed.

The above configuration performs the following operations.

Normally, only the pivot shaft 526 swings.

Therefore, the locking tool 541 is attached to the bottom surface 538a or the rear surface 5.
It is located on 38b and swings while sliding.

When switching the arm pressure, the motor 543 is rotated and the gear plate 537 is rotated, that is, the cam plate 538 is rotated to switch the sliding surface of the locking tool 541 and change the rotational position of the lever 524.

It goes without saying that the cam plate 37 in the first embodiment can be changed to be driven by a motor via a worm and a helical gear.

Further, in the first embodiment, switching is performed using a notch, a pawl, and a motor that rotates the pawl, but it is obvious that the same effect can be obtained by using other known ratchet mechanisms. .

[Effects] According to the wiper device according to the first aspect, the wiper blade pressing pressure can be easily changed with a simple configuration in which a cam member provided relatively rotatably around a pivot shaft is rotated by a rotation drive means.

[Brief explanation of the drawing]

1 to 10 show a first embodiment of the present invention, FIG. 1 is a sectional view of the main part taken along the line A-A in FIG. 3, and FIG. 2 is a sectional view taken along the line B-B in FIG. 3. 3 is a cross-sectional side view of the wiper device, FIG. 4 is a plan view of the wiper device, FIG. 5 is a plan view of the front of the vehicle equipped with the wiper device, and FIG. 6 is a pressure lever. 7 is a perspective view of the cam plate, FIG. 8 is a conceptual diagram of the pressing pressure changing mechanism, FIG. 9 is a block diagram of the control section, FIG. 10 is a control flowchart, and FIGS. 11 to 17 11 shows a second embodiment of the present invention, FIG. 11 is a plan view of the wiper device, FIG. 12 is a sectional side view of the wiper device, and FIG. 13 is a sectional view of essential parts taken along line C-C in FIG. 11. , 14th
The figure is a sectional view of the main part taken along the line D-D in Fig. 13, Fig. 15 is a sectional view of the main part taken along the line E-E in Fig. 13, Fig. 16 is a sectional view of the locking tool, and Fig. 17 is a perspective view of the cam plate, No. 18
FIG. 19 shows a third embodiment of the present invention, and FIG.
Fig. 8 is a cross-sectional side view of the wiper device, Fig. 19 is a perspective view of the cam plate and pressure lever, the lever showing a cutaway perspective view of the base end, and Fig. 20 is a fourth embodiment of the present invention. 21 and 22 are cross-sectional views of the pawl provided on the motor shaft, showing
The figures show a fifth embodiment of the present invention, with FIG. 21 being a sectional side view of the wiper device, and FIG. 22 being a perspective view of the cam plate. 10... Wiper blade 20. 120... Wiper arm 21,... Fixing member 24.124.224.524... Pressure lever 25.
125...Spring member 26.126.526...Pivot shaft 35...Piston 37.138.238.538...Cam plate (cam member) 38.142...Claw body 39.143...・Motor (claw body moving means) 137.5
37...Gear plate (ratchet gear) 543...Motor (rotation drive means) 51st! l No. 71! I Fig. 8 11%IL+ 15th wJ Fig. 16 17YIB

Claims (1)

[Claims] A fixed member is provided on a pivot shaft that rotates reciprocally and rotates integrally with the pivot shaft, and one end is pivotally supported by the fixed member and is rotatable in a direction perpendicular to the rotating surface of the fixed member, and a wiper blade is attached to the other end. a wiper arm to be held; a pressure lever that is pivotally supported by the fixed member and rotates and changes the tension of a spring member stretched between the wiper arm and the wiper arm according to the rotational position; and a pressure lever that rotates around the pivot axis. A wiper device for a vehicle, comprising: a cam member that is relatively rotatable and has a cam surface formed on its peripheral surface and one end of the pressure lever is brought into contact with the cam member; and a rotational drive means for rotating the cam member. .