JPS5893653A - Wiper capable of varying set load on its blade - Google Patents

Abstract

PURPOSE:To simplify the operation of varying the set load on the wiper blade by a method wherein a tension member is applied to an inclined surface of a movable member and the load applied on an arm is varied through the tension member by the movement of the movable member. CONSTITUTION:A movable member 13 is attached to an arm head 4 in such a manner that the member 13 slides only in the longitudinal direction of the arm head 4 and the movement of the member 13 in that direction is effected by a cam 12. Further, the inclined surface 13e is formed on the upper surface of one end of the member 13 in such a manner that the surface 13e does not run parallel to the axis 3 of the wiper. In addition, arm retainers 15 are attached to the arm 5 so as to extend outwardly of one end of the arm 5 and the tension member 16 is supported by the retainers 15. The tension member 16 comprises a shaft 18 projecting downwardly from a case 17 and provided with a roller 18a at the top end thereof, a coil spring 19 arranged on the upper surface of the shaft 18 and a bolt 21 for adjusting the pressure of the spring 19 and the roller 18a of the shaft 18 is brought into pressure cntact with the inclined surface 13e of the movable member 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wiper device for wiping a window surface of an automobile or the like, in which the set load of the wiper blade that is pressed against the window surface is variable.

In this type of wiper device, when the vehicle speed or the relative wind speed changes, the speed of airflow hitting the wiper blade pressed against the window surface changes, and the lifting force acting on the blade also changes. Therefore, the pressing pressure of the wiper blade against the window surface changes, resulting in a drawback that the wiping performance of the wiper blade varies depending on the driving conditions of the automobile.

Conventionally, to solve this problem, an arm head with one end fixed to a wiper shaft that rotates back and forth, and a wiper that is connected to the other end of the arm head via a pivot pin and has a tip end that wipes the window surface of the car. A spring that presses the blade against the window surface is provided between the arm that holds the blade, and an actuator is connected to this spring, and the output of the actuator causes the spring to expand and contract, thereby reducing the tension. Technique 1'6 is known in which the set load of the wiper blade is changed so that the pressing pressure of the wiper blade against the window direction is kept almost constant regardless of the driving state of the automatic vehicle.

However, in this device, the actuator is directly extended in a suffling manner, and the set load of the wiper blade is varied according to the tension, so the actuator requires a large force, and the actuator is large and heavy. There is also a drawback that the spring requires high precision due to the fact that the tension of the spring is changed through the intervention of such an actuator.

The present invention eliminates the above-mentioned conventional drawbacks, and also varies the set load of the wiper blade with a relatively small number of points.
To provide a wiper device with a variable set load of wiper blades, which allows the blades to wipe the window in a good direction even when the lift force acting on the wiper blades increases, such as when the vehicle speed or relative wind speed increases. The purpose is to

Hereinafter, the present invention will be explained in detail with reference to one embodiment shown in FIGS. 1 to 6.

The flange portion 1a is fixed to the vehicle body 2. Numeral 3 is a wiper shaft which is supported by the pivot 1 and rotates back and forth, and 4 is an arm head whose one end is fixed to the wiper shaft 3. Reference numeral 5 denotes an arm, and the arm 5 has a channel 5 supported at one end on a pivot pin 6 fixed to the other end of the arm head 4.
a, and a rod 5b fixed to the other end of the channel 5a with a rivet 7. A wiper blade 9 which is pressed against the window surface 8 is attached to the tip of the rod 5b as shown in FIG.

Reference numeral 10 denotes a spring stretched between the arm °' rad and the arm 5, and is hooked to a rod 5b at one end of the spring.
The other end is hooked to a support pin 11 fixed to the arm head 4.

12 is a cam pivotally connected to the pivot 1. This cam 12
A lever 12a is provided.

13 engages with the arm head 4 and is moved in the longitudinal direction of the arm head 4 by the cam 12 (as indicated by the arrow in FIG. 1).
It is a movable member that is moved substantially perpendicularly to the axial direction of the wiper 41]3, and is hollow inside, and
+ Elongated hole 13b formed in 13a.

13b engages with the engagement pins 14 and 14a attached at intervals in the longitudinal direction of the arm head 4, respectively, and the movable part @1
3 to the arm head 4 in the vertical and horizontal directions d' in FIG.
It can be slid only in the longitudinal direction.

One surface of the movable part side 13, the upper surface in the illustrated embodiment, is connected from the arm head 4 side to the long groove 13C1 flat surface 13d, and -
It is an inclined surface 13e that reaches the end edge. This slope 1
3e is an inclined surface that is not perpendicular to the axial direction of the wiper shaft 3. Further, on the lower surface, engagement protrusions 13f and 13g capable of engaging with the cam 12 are provided near both ends thereof.

15 is channel 5 & of arm 5 to arm 4
It is a rigid arm retainer extending to the side, and may be formed integrally with the channel 5IL, or may be formed separately and fixed to the i-channel 5a.

16 is the arm retainer 15. The tension part row is supported by the movable part 13 and pressed against the upper surface of the movable part 13, and has a structure as shown in FIG. 3, for example.

In FIG. 3, the tension member 16 has an opening 17 at the bottom.
a shaft member 18 having a large diameter portion hooked to the bottom surface of the case 17 within the case 17, a small diameter portion protruding downward from the opening 17a, and a roller 8a provided at the tip.
A coil spring 19 disposed on the upper surface of the large diameter portion of the shaft member 18 and a bolt 21 screwed together with a female thread 17b formed on the upper l of the case 17 and brought into contact with the upper surface of the coil spring 19 via a washer 20. It consists of This Porto 21 is
This is for adjusting the hexagonal pressure of the coil spring 19.

Next, the operation of the variable set load wiper device for wiper blades according to the present invention will be explained with reference to FIGS. 4 to 6.

Now, assuming that the cam 12 is in the position shown in FIG.
3g and engages with the locking projection 13f on the opposite side, the movable member 13 moves in the longitudinal direction of the arm head 4 in the direction of arrow E shown in FIG. 4(A), and as shown in FIG. When the lever 12a rotates approximately 180 degrees, the movable member 13
The amount of movement becomes the maximum.

At this time, the movable member is pressed against the roller 18&.

The position of the upper surface of 13 changes from an inclined surface 13e to a flat surface 13d. Therefore, the coil spring 19 is compressed, and the spring pressure of the coil spring 19 increases.

Here, FIG. 86 is an explanatory diagram showing the principle of the present invention. The distance from the pivot pin 6, which is the fulcrum of the arm 5, to the support point of the wiper blade 9 is L, and the degree setting load of the wiper blade 9 is P. In addition, if the distance from the pivot pin 6 to the tension member 16 is l, and the reaction force due to the spring pressure of the coil spring 19 is F, then the relationship LXP=exF holds. Since the length of the distance e is constant -1el, the set load P of the wiper blade 9 is equal to the reaction force F due to the coil spring 19.
is proportional to.

Therefore, when the movable member 13 moves from the position shown in FIGS. 4 to 5, the spring pressure of the coil spring 19 increases, and the pressure F also increases from Fl to F2, and the set load P It increases from F2 to F2.

Here, when the movable member 13 moves to the position shown in FIG. 51, the engagement pin 14 is made to reach one end of the elongated hole 13b.

By reciprocating the wiper shaft 3 with a wiper drive device (not shown), the arm throat 4, arm 5, and wiper blade 9 reciprocate integrally with the wiper shaft 3, and the movable member 13 moves from the cam 12 to the arm. However, the positional relationship between the arm head 4 and the movable member 13 does not shift at all in the direction of the arrow E shown in FIG. Since the coil spring 19 pushes the flat surface 13d of the upper surface of the movable member 13 in the direction of the arrow G shown in FIG. This makes it more difficult to shift.

When the member 13 is moved to the position shown in FIG. Slope 13e
The recess 13h is provided in.

The movable member 13 is moved to the position and is pressed by the roller 18a.
The position of the upper surface changes from the flat surface 13d to the inclined surface 13e δ Therefore, the coil spring 19 expands, the pressure F exerted by the spring 19 decreases from F2 to Fl, and the set load P of the wiper blade 9 decreases from F2 to Pl. do. When the movable member 13 moves to the position shown in FIG.
If the movable member 13 is moved away from the cam 12 due to the rotation of the wiper shaft 3, the movable member 1
The positional relationship between 3 and arm head 4 is 4th LXl (a)
There is no deviation at all in the direction of arrow G shown in FIG. 4, and since the roller 18a is in pressure contact with the slope 13e, a component force in the direction of arrow G acts on the movable part 13, as shown in FIG. 4(A). Arrow Lord goes in one direction, Zureo. 8. ,, big.

In other words, when the vehicle speed or relative wind speed increases and the lift force acting on the wiper blade 9 becomes thicker, the movable member 13 is moved by the cam 12, and the positional relationship between the movable member 13 and the arm head 4 is changed as shown in FIG. When the centrifugal load P of the wiper blade 9 is increased in the state shown in FIG. Since the set load P of the wiper blade 9 is reduced by changing the positional relationship to the state shown in FIG. 4, the pressing pressure of the wiper blade 9 against the window surface 8 can be kept almost constant regardless of the driving state of the vehicle. This makes it possible to maintain good wiping performance of the blade 9, ensure visibility for the occupants, and improve safety.

The set load P of the wiper blade 9 can be changed by a simple operation of moving the movable member 13 in the longitudinal direction of the arm head 4 using the cam 12, and the output is as large as the conventional one. Compared to a device that uses an actuator to extend and retract a splint knob provided between an arm and an arm head and change the tension thereof to change the set load, the device is smaller and weighs less.

A part of the set load P of the wiper blade 9 is also applied from a spring 10 stretched between the arm head 4 and the arm 5, but in the present invention, the tension member 1
6 is provided, the spring 10 can be extremely weak and the tension of the spring 10 is always constant, and the spring 10 does not require high dimensional accuracy as in the conventional case, and its design becomes easy. Further, since the tension member 16 is provided, this spring 10 may be omitted.

In addition, the tension m The reaction force F due to the spring pressure of the coil spring 19 is varied by the bolt 21 of the material 16, and the wiper blade 9
The set load P of can be adjusted. Although the wiper cam 12 is pivotally connected to the pivot 1, it is also possible to pivotally connect it to the wiper shaft 3.

As explained above, the variable set load wiper device for wiper blades according to the present invention includes a movable member having an inclined surface not perpendicular to the bearing direction of the wiper shaft on one surface of the movable member. and a tension member pressed against the tension member, and by moving the movable member in the longitudinal direction of the arm head using a cam, the position on one surface of the movable member that is pressed against the tension member is changed, and the spring pressure of the tension member is applied. By changing the reaction force and making the set load of the wiper blade variable, the variable operation is simple, and unlike conventional methods, the spring can be expanded and contracted using a large output actuator, and the tension can be changed to adjust the set load of the wiper blade. Compared to a variable type device, the device is smaller and weighs less, and the spring does not require high dimensional accuracy, making the spring easier to design.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a variable set load wiper device for wiper blades according to the present invention, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIG. Enlarged cross-sectional front view of the member, Figures 4 (A) and 5 (A)
2A and 2B are explanatory diagrams showing the principle of operation of the present invention, respectively.

Claims (1)

[Claims] 1) A wiper shaft that is supported by a pivot and rotates back and forth, an arm head that has one end fixed to the wiper shaft, and an arm that has one end supported on the other end of the arm head via a pivot pin. and a wiper blade attached to the other end of the arm and pressed against the window surface, the wiper blade having a cam pivotally connected to the pivot or the wiper shaft, and a cam that engages with the arm head and causes the arm head to be moved by the cam. a movable member that is moved in the longitudinal direction and has an inclined surface on one side F that is not orthogonal to the axial direction of the wiper shaft; an arm retainer that extends from the arm toward the arm head; A wiper device with a variable set load for a wiper blade, comprising a tension member pressed onto one surface of a movable member.