GB2201585A

GB2201585A - Windscreen wiper operating mechanism

Info

Publication number: GB2201585A
Application number: GB08803795A
Authority: GB
Inventors: David Baynham
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-03-03
Filing date: 1988-02-18
Publication date: 1988-09-07
Anticipated expiration: 2008-02-18
Also published as: GB8803795D0; GB2201585B

Abstract

In a windscreen wiper arrangement comprising wiper 60 mounted on arm 52 connected to drive shaft 51 of wiper motor 50, the wiper is rotated about the axis of arm 52 by another motor 54 via transmission gearing 55, 56, 58, 59 whilst it is moved to and fro across windscreen 61. The wiper may be a conventional wiper blade, or cylindrical structure with radially-extending blades, or a bristled brush. In other embodiments, the wiper is not rotated about the axis of the wiper arm, but wiper and arm are subjected to an additional motion during the course of normal to and fro movement. This may be effected by imparting a rocking motion to a pivotally-mounted drive motor, or by linearly displacing a drive motor against the bias of springs, or by vibrating the drive motor. Improved cleaning action is said to result. <IMAGE>

Description

VEHICLE WINDSCREEN WIPER SYSTEM This invention relates to a vehicle windscreen wiper system.

It has been noticed that windscreen wiper systems do not always wipe the windscreen surface completely clean, particularly if the windscreen washer liquid is only pure water and does not contain any added cleaner or detergent. It is believed that this is often due to oil and oily polluting substances being lifted from the road surface by the tyres of other vehicles, flung into turbulent air and thus deposited on the windscreen, possibly together with water. The result is that the oil or other pollutant is simply smeared over the whole surface by the windscreen wiper blade.

The principal object of the present invention is to help to clean the surface of a windscreen adequately by physical means alone as distinct from the use of chemical solvents added to the water in the washer system.

Accordingly, the present invention consists in a vehicle windscreen wiper system which includes at least one motorised windscreen wiper blade which is carried by an arm and which is adapted to be moved in opposite directions of. movement one at a time over the surface of the windscreen, and drive means operable to impart additional motion to said blade during its movement in each of said opposite directions.

In a first embodiment of the system according to the present invention, the wiper blade is rotated about the longitudinal axis of said arm.

In a second embodiment of the system according to the present invention, said arm is drivingly connected to a windscreen wiper motor which is mounted for rocking movement about an axis of rotation and which is connected by a rod to a second motor, said rod being connected to the second motor eccentrically, whereby the windscreen wiper blade is lifted off and drawn into contact with the surface of the windscreen by the action of the second motor on the wiper motor and on said rod as the blade is moved across said surface by the driven arm.

In a third embodiment of a windscreen wiper system according to the present invention, said arm is drivingly connected to a windscreen wiper motor which is mounted for rocking movements about an axis of rotation and which is connected by a rod to a second motor, said rod being connected to the second motor eccentrically and being operable to move the windscreen wiper motor in opposite directions one at a time relatively to the windscreen in directions substantially parallel to the surface of the windscreen, whereby the windscreen wiper blade is not only caused to move across the windscreen surface by the driven arm but is also caused to make additional movements in opposite directions during said movement across the windscreen surface.

In a fourth embodiment of a windscreen wiper system according to the present invention, said arm is drivingly connected to a windscreen wiper motor which is so mounted as to be capable of making sliding movements substantially parallel to the windscreen surface, a cam plate carried by or integral with said wiper motor being kept firmly in contact with a cam by spring means, and said cam being driven by a second motor, whereby rotation of the cam during drive of said arm by said wiper motor will result in additional movements parallel to the windscreen surface and in opposite directions being imparted to said blade during its movement across the windscreen surface by the wiper motor.In one form, said fourth embodiment can comprise opposed L-shaped slides of which one limb of each slide overlies the wiper motor, compression springs acting upon one end of the wiper motor to maintain the cam plate on the other end thereof to bear against said cam. In another form, said fourth embodiment can comprise a yoke-shaped member through whose oppositely-directed limbs there extend guide bolts, the cam being in contact with a first surface of the central portion of said member and the wiper motor being mounted upon a second surface of said central portion opposite to the first surface thereof.

Some embodiments of a vehicle windscreen wiper system, given by way of example only, will now be more particularly described with reference to the accompanying diagrammatic drawings, in which : Figures 1 and 2 illustrate a side elevation and a front elevation, respectively, of a second embodiment of said system, Figure 2 being a view seen looking in the direction indicated by the arrow X in Figure 1; Figure 3 illustrates (in a side elevation similar to that of Figure 1) a third embodiment of said system; Figure 4 illustrates (again, in a side elevation similar to that of Figure 1) a fourth embodiment of said system; Figure 5 illustrates another form of said fourth embodiment; and Figure 6 illustrates a front elevation of the first embodiment of said system.

Referring to Figures 1 and 2 which illustrates a second embodiment of a system according to the present invention, the glass of the windscreen is indicated by the reference numeral 10. An arm 11 is connected to and driver by a wiper motor 12 in any convenient manner and carries a wiper blade 13. The motor 12 is mounted on a roller bearing 14 for rocking movements about an axis 15, the rocking movements being imparted to said motor 12 by a motor 16 through the intermediary of a rod 17 whose one end is connected at 18 to the motor 12 and whose other end is connected eccentrically at 19 to said motor 16. The two motors 12, 16 are mounted on a base plate 20 which will be suitably positioned in the vehicle.

In operation, this embodiment is such that, when the motor 12 is in operation and when the vehicle driver decides that enhanced cleaning is desirable, the motor 16 is activated by the driver operating an ON/OFF switch in order to cause the motor 16, through the rod 17, firstly to move the motor 12 angularly in an anti-clockwise direction about the axis 15 and secondly to move said motor 12 angularly in a clockwise direction about said axis. Of course, the swinging or reversing movements of the motor 16 are not considerable because all that is required is for the windscreen wiper blade 13 to be lifted off the surface of the glass 10 and then to be brought back into contact with said surface, all of this taking place cyclically during the normal and familiar sweeping movements of the windscreen wiper.The ON/ OFF switch used by the driver tovturn the motor 16# on (and to turn it off again when it is considered that the windscreen has been adequately cleaned) is not shown in Figures 1 and 2 but the provision thereof is considered to be within the capability of any competent craftsman.

Referring to Figure 3, in which components similar to or identical with those shown in Figures 1 and 2 are identified by the same reference numerals, the illustrated third embodiment of a windscreen wiper system according to the present invention differs from the second embodiment thereof in that the rocking movements imparted to the motor 12 when the motor 16 has been activated resulted in the working edge or surface(s) of the blade 13 is/are moved in opposite directions one at a time relatively to the surface of the glass 10 in directions which are substantially parallel to said glass surface, Therefore, in this case, the action carried out by the blade 13 when the motor 16 is running could be described as a scrubbing action.

Referring now to Figure 4, which illustrates one form of a fourth embodiment of a system according to the present invention, a base plate 20 supports a windscreen wiper motor 12 which drives an arm 11 which carries a wiper blade 13. .However, unlike the second and third embodiments, in this form of the fourth embodiment the motor 12 is mounted for sliding movements along the base plate 20; said sliding movements are guided by virtue of the motor 12 being arranged between parallel L-shaped slides 30 of which one limb in each case overlies part of the motor 12.

A cam plate 31 is carried by the motor 12, said plate 31 being in contact with a cam 32 which is fixed to a shaft 33 whose one end is journalled in a bearing 34 and whose other end is drivingly connected to a motor 35. Compression springs 36 maintain contact between the plate 31 and the cam 32.

When the vehicle driver activates the motor 35, the cam 32 rotates and the first angular movement of the cam causes the motor 12 to move firstly, say, to the left as seen in Figure 4, thereby compressing the springs 36; continued angular movement of the cam 32 about its axis of rotation permits the power stored in the springs 36 to move the motor 12 to the right as seen in Figure 4. Such movements are repeated cyclically. Therefore, the wiper blade 13 performs a scrubbing action on the glass 10 because said blade is moved in directions parallel to the surface of the glass.

In Figure 5, which illustrates another form of the fourth embodiment of a system according to the present invention, a base plate 20 supports a windscreen wiper motor 12 which is mounted on a socalled yoke-shaped member 40; oppositely directed limbs 41 of the member 40 are apertured to enable guide bolts 42 to extend through them and to be screwed into tapped holes in the base plate 20.

Buffers 43 are provided in order to mount the member 40 and hence the motor 12 in a resilient manner; said buffers may be washers or the like made of an elastomeric material or they could be compression springs. Another motor (not visible in Figure 5 but which could be similar to the motor 35 of Figure 4) is drivingly connected to a cam 44 which, when the cam-driving motor is activated, will cause the member 40 and the motor 12 to vibrate upwardly and downwardly; such upwards/downwards movements of the motor 12 will cause the blade 13 to be moved in directions parallel to the surface of the windscreen glass and, therefore, the action of the blade will be a scrubbing action.

Of course, in place of the cam mechanism, the two forms of the fourth embodiment could utilize a linkage in conjunction with a motor which will produce a rocking (reversing) motion as was the case with the motor 16 in Figures 1 to 3.

Referring lastly to Figure 6 which illustrates the first embodiment of the system according to the present invention, a windscreen wiper motor 50 has an output shaft 51 to which an arm 52 is connected; said arm 52 may conveniently comprise a shaft made of, for example, fibre glass or GRP material and one end of said shaft may include a clamp 53 for securing the arm to the shaft 51. A second motor 54 has an output shaft which carries a gear 55 whose teeth mesh with those of a pinion 56 which forms part of a unit whose other parts are a sleeve 57 and a bevel gear 58. The bevel gear 58 meshes with a complementary bevel gear 59 which is fast with a so-called windscreen wiper "blade" 60.Said blade 60 may have a form similar to that/those of existing blade(s) or it could, for example, have the form of a bristled brush or it could comprise a number of radially outwardly directed elongate ribs which are appropriately spaced from one another around the longitudinal axis of the gear 59/blade 60 unit. The arrangement will be such that, when the vehicle driver operates the motor 54'in order to rotate the blade 60, said motor 54 could drive the rotary blade 60 intermittently in any convenient manner or it could drive said blade 60 continuously, the intermittent or continuous drive thereof resulting in an additional motion imparted to said blade during its movement (by the motor 50/arm 52) across the surface of the glass windscreen 61.

It is to be understood that, in the case of each embodiment, an ON/OFF switch is provided in order to enable the vehicle driver to start and stop the motor which imparts the additional component of movement to the blade when the extra cleaning of the windscreen has been carried out to the driver's satisfaction.

Claims

CLATMS:-

1. A vehicle windscreen wiper system which includes at least one motorised windscreen wiper blade which is carried by an arm and which is adapted to be moved in opposite directions of movement one at a time over the surface of the windscreen, and drive means operable to impart additional motion to said blade during its movement in each of said opposite directions.

2. A system as claimed in Claim 1, wherein the wiper blade is rotated about the longitudinal axis of said arm.

3. A system as claimed in Claim 2, wherein said rotation of the wiper blade is effected by means of a gear drive from a motor which is independent of the motor which drives the windscreen wiper blade.

4. A system as claimed in Claim 1, wherein said arm is drivingly connected to a windscreen wiper motor which is mounted for rocking movement about an axis of rotation and which is connected by a rod to a second motor, said rod being connected to the second motor eccentrically, whereby the windscreen wiper blade is lifted off and drawn into contact with the surface of the windscreen by the action of the second motor on the wiper motor and. on said rod as the blade is moved across said surface by the driven arm.

5. A system as claimed in Claim 1, wherein said arm is drivingly connected to a windscreen wiper motor which is mounted for rocking movements about an axis of rotation and which is connected by a rod to a second motor, said rod being connected to the second motor eccentrically and being operable to move the windscreen wiper motor in opposite directions one at a time relatively to the windscreen in directions substantially parallel to the surface of the windscreen, whereby the windscreen wiper blade is not only caused to move across the windscreen surface by the driven arm but is also caused to make additional movements in opposite directions during said movement across the windscreen surface.

6. A system as claimed in Claim 1, wherein said arm is drivingly connected to a windscreen wiper motor which is so mounted as to be capable of making sliding movements substantially parallel to the windscreen surface, a cam plate carried by or integral with said wiper motor being kept firmly in contact with a cam by spring means, and said cam being driven by a second motor, whereby rotation of the cam during drive of said arm by said wiper motor will result in additional movements parallel to the windscreen surface and in opposite directions being imparted to said blade during its movement across the windscreen surface by the wiper motor.

7. A system as claimed in Claim 6, wherein there are opposed L-shaped slides of which one limb of each slide overlies the wiper motor, compression springs acting upon one end of the wiper motor to maintain the cam plate on the other end thereof to bear against said cam.

8. A system as claimed in Claim 6, wherein there is a yoke-shaped member through whose oppositelydirected limbs there extend guide bolts, the cam being in contact with a first surface of the central portion of said member and the wiper motor being mounted upon a second surface of said central portion opposite to the first surface thereof.

9. A vehicle windscreen wiper system constructed, arranged and adapted to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying diagrammatic drawings.

10. Any features of novelty, taken singly or in combination, of the embodiments of the invention hereinbefore described with reference to the accompanying diagrammatic drawings.