GB2259851A

GB2259851A - A drive transmission device for wiper blades, in particular for the wiper blades of a vehicle windscreen

Info

Publication number: GB2259851A
Application number: GB9219046A
Authority: GB
Inventors: Antonio Toaldo; Vanni Portesan
Original assignee: Fister SpA
Current assignee: Fister SpA
Priority date: 1991-09-09
Filing date: 1992-09-09
Publication date: 1993-03-31
Also published as: ITTO910207V0; ES1023349U; FR2681023A1; ITTO910207U1; ES1023349Y; IT223283Z2; GB9219046D0; DE4229992A1

Abstract

A drive transmission device 1 for wiper blades is provided with a plurality of rods 5, 5', 8 pivoted to each other and to the body 3 of a vehicle so as to define an articulated quadrilateral 4 adapted to be pivoted relative to the body 3 between two extreme angular positions. The articulated quadrilateral 4 carries adjacent first 10 and second 11 blades, of which the first blade 10 is connected to rod 8 for moving together therewith, and the second blade 11 is connected to the articulated quadrilateral 4 by a connecting assembly 15. The connecting assembly 15 is provided with a rocker bar 17 which cooperates with the articulated quadrilateral 4 to pivot the second blade 11 relative to the articulated quadrilateral 4 itself during its movement between the two extreme angular positions. <IMAGE>

Description

1 A DRIVE TRANSMISSION DEVICE FOR WIPER BLADES, IN PARTICULAR FOR THE

WIPER BLADES OF A VEHICLE WINDSCREEN The present invention relates to a drive transmission device for wiper blades, particularly for the wiper blades of a vehicle windscreen.

To wipe windscreens, in particular to wipe windscreens with a more complex geometry than that of traditional windscreens, the known method is to use several blades, at least two, placed adjacent each other and fixed to a drive-transmission device comprising, in most applications, a system of rods pivotally connected to each other and to the body of a vehicle so as to define a pantograph- type articulated quadrilateral adapted to pivot between two extreme angular positions.

In prior art arrangements, a first such blade is connected to a free end portion of the articulated quadrilateral so that it can pivot relative to the quadrilateral itself during pivoting of the latter between the said extreme angular positions.

A second such blade is, on the other hand, positioned between the first blade and the points at which the articulated quadrilateral is pivoted on the vehicle body, and is f ixed for pivoting to a rod of the articulated 2 quadrilateral itself. In particular, this second blade is connected to the said rod so that, whatever the angular position of the articulated quadrilateral between the extreme positions, it has a free end portion facing a free end portion of the first blade.

Such a method of connecting the blades to the articulated quadrilateral, although commonly used, has an operational disadvantage in that it limits the area wiped by the blades. In other words, though the way the first blade is fixed to the articulated quadrilateral may be considered acceptable in practice, the same cannot be said for the second blade which, as it is fixed to one of the rods of the articulated quadrilateral itself, in use wipes a strip, in this case of a windscreen, the width of which depends exclusively on the angle of rotation of the articulated quadrilateral and therefore on the angle between the two extreme angular positions of the articulated quadrilateral itself.

An object of the present invention is to provide a drive-transmission device for wiper blades which'avoids the disadvantage just described, in particular which enables a greater area to be wiped for the same angle of rotation of the articulated quadrilateral and which is at the same time both simple and economical to manufacture.

According to the present invention, a drive transmission 1 h 3 device f or wiper blades is provided, in particular for the windscreen wiper blades of a vehicle, the said device including a plurality of rods, pivotally connected to each other and to the body of the vehicle so as to def ine an articulated quadrilateral adapted to be pivoted relative to the said vehicle body between two extreme angular positions, the said articulated quadrilateral having f ixed to it at least one f irst and at least one second blade, the blades being adjacent, characterised in that it includes connecting means interposed between the said articulated quadrilateral and the said second blade and connected to the said articulated quadrilateral so as to pivot the said seccnd blade relative to the articulated quadrilateral itself during at least part of the movement of the latter between the said extreme angular positions.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:- Figure 1 is a schematic frontal view of a preferred embodiment of a drive- transmission device for vehicle windscreen wiper blades according to the present invention mounted on the vehicle; Figure 2 illustrates a detail of Figure 1, on a greatly enlarged scale and substantially in block form; Figure 3 illustrates a variant of the detail of Figure 2 on a greatly enlarged scale; and 4 Figure 4 is an enlarged, detailed section taken on the line IV-IV of Figure 2.

In Figures 1 and 4, a drive-transmission device for the windscreen wiper blades of a windscreen 2 (Figure 1) of a vehicle (not shown) is shown at 1.

The device 1 includes a plurality of rods pivotally interconnected and adapted to be pivoted on the body 3 of the vehicle (not shown) so as to define an articulated quadrilateral 4 of the type commonly known as a pantograph. In particular, this articulated quadrilateral 4 is defined by first and second spaced-apart rods 5 and 5 9, each of which has one end nearer the body 3 of the vehicle (not shown) connected to the body 3 itself f or pivoting about a respective axis indicated 6 (Figure 1), and its other end connected by a pivot 7 to an axial end rod 8.

Still with reference to Figure 1, the articulated quadrilateral 4 is able to pivot about the axes 6 between two extreme angular positions thanks to an actuator assembly 9, known and therefore not described in detail, and carries first and second wiper blades 10, 11 fixed to it. In particular, the articulated quadrilateral 4 is to be moved between a first position, corresponding to a rest position of the device 1 in which the first and second rods 5. 51 are adjacent a bonnet adaDted 1 (not illustrated) of the vehicle (not illustrated), and a second position, indicated in broken outline in Figure 1, in which the first and second rods 5, 51 are substantially adjacent a pillar (not shown) of the vehicle (not shown).

is Still with reference to Figures 1 and 4, the first wiper blade 10 is fixed by an associated support bracket 13 to an end portion 14 of the end rod 8 which projects past the pivot 7 connecting it to the first rod 5, while the second blade 11 is fixed to the articulated quadrilateral in a position adjacent the first blade 10 so that an end portion of the second blade 11 is facing an end portion of the first blade 10 itself, whatever the angular position of the articulated quadrilateral 4 between the said extreme angular positions.

The second blade 11 is fixed to the articulated quadrilateral 4 by an interposed fixing assembly 15 which is part of the device 1.

With reference to Figure 1, but especially to Figures 2 and 4, this fixing assembly 15 includes a rod 16 extending transverse the first and second rods 5, 51 of the articulated quadrilateral 4 and, in use, between the first and second rods 5,1 51 themselves and the windscreen 2, and an articulated rocker arm 17 controlled by the rod 16 and extending between the first rod 5 itself and the 6 windscreen 2.

The rod 16 has a first end which cooperates with a lateral surf ace 18 (Figure 4) of the second rod 51 and f acing, the windscreen 2, in use, and is pivoted on an intermediate portion of the second rod 51 by a pivot pin 19 so as to pivot about an axis 191 (Figures 1, 2 and 4) orthogonal to the plane of Figure 2 and to the second rod 51. The rod 16 has a second end connected to a first end of the rocker arm 17 by a pivot 20 so as to enable the rocker arm itself to pivot relative to the rod 16 about an axis 21 substantially parallel to the axis 191.

is As shown in Figure 4, the first rod 5 has a projection 22 which is fixed to an intermediate portion of the first rod 5 and, when the device 1 is mounted on the vehicle, extends towards the windscreen 2. An intermediate portion of the rocker arm 17 is pivotally connected to this projection 22 by a pivot pin 23 so as to allow the rocker arm 17 to pivot about an axis 231 parallel to the axes 191 and 21.

The second end of the rocker arm 17 is f ixed to the second blade 11 by an interposed, elastically def ormable, flexible blade 24 which is arranged to urge the second blade 11 into contact with the windscreen 2 with a predetermined f orce, and to permit small movements of the second blade 11 towards and away from the windscreen 2 7 itself and relative to the first and second rods 5, 5'.

In use, the actuation of the actuator 9 causes the articulated quadrilateral 4 to be pivoted about the axes 6 and consequently the blades 10 and 11 to be moved between a first angular position, corresponding to the rest position of the articulated quadrilateral 4 itself, and a second angular position corresponding to the second extreme position of the articulated quadrilateral 4.

When the blades 10, 11 lie in their first angular position, they are substantially aligned with each other and extend substantially parallel to and adjacent the first rod 5.

When, on the other hand, the blades 10, 11 lie in the second angular position, the first blade 10 is positioned substantially adjacent the pillar (not shown) of the vehicle (not shown) and is pivoted anticlockwise relative to the first rod 5, while the second blade 11 is also pivoted anticlockwise relative to the first rod 5 and is positioned substantially adjacent a side edge 25 (Figure 1) of the windscreen 2.

While passing from the first to the second angular position, the first blade 10 moves together with the end rod 8 and its ends describe respective curves 26, 27 indicated by broken lines in Figure 1.

8 During the same movement, the first and the second rods 5, 5 1 move relative to each other as a result of being pivoted at different points; therefore the rod 16 and the rocker arm 17, which are hinged to the second rod 51 and to the f irst rod 5 respectively, pivot relative to the first and second rods 5, 51 themselves about respective axes 231 and 191, and relative to each other about the pivot 20 so as to increase an angle a (Figure 2) defined between them.

An increase in the angle a involves an anticlockwise pivoting of the rocker arm 17 and the consequent pivoting, in the same sense, of the second blade 11, the opposite ends of which describe two arcs 28, 29, indicated by chain lines in Figure 1.

The variant illustrated in Figure 3 relates to a device 30 similar to the device 1, the parts of which are indicated with the same numbers as the corresponding parts of the device 1.

In the device 30, the second blade 11 is joined to the articulated quadrilateral by a connecting assembly 32 including a rocker bar- 33. which extends transverse the first and second rods 5, 51 and has an intermediate portion hinged to the first rod 5 for pivoting about an axis 34 orthogonal to the plane of Figure 3 and to the first rod 5 itself.

9 The rocker bar 33 also has one end portion 35, which is substantially L shaped, extending outside the first rod and fixed to an end of the flexible blade 24, and an opposite end portion 331 joined to the second rod 51 by a coupling 36.

This coupling 36 is arranged to allow the rocker bar 33 to pivot relative to the second rod 51 about an axis orthogonal to the plane of Figure 3 and to the second rod 51 itself, and to allow the end 331 of the rocker bar 33 itself to move parallel to the second rod 51.

In particular, with reference still to Figure 3, the coupling 36 is constituted by a pin 37 fixed to the end 331 of the rocker bar 33 and slidable axially in an associated axial guide and retaining channel formed in the second rod 51.

In use, the axial movement of the first and second rods 5, 51 relative to each other, produced by the pivoting of the articulated quadrilateral 4 from the first to the second extreme angular position, involves a rotation of the rocker bar 33 about the axis 34, in particular an anticlockwise rotation which results in the second blade 11 turning in the same sense relative to the adjacent first rod 5.

It its evident from the above description that the z devices 1 and 30 both have the advantage of enabling a not inconsiderable increase in the working surface wiped by the blades 10, 11 to be achieved. In f act, with reference to Figure 1, if A indicates a surface wiped in use of prior art devices, this surface ending laterally substantially at the first rod 5 (in f act the second blade 11 was f ixed to this), when either device 1 or device 30 is used, the surf ace A is increased by the hatched area indicated B in Figure 1. From this drawing, it is clear that this area B widens the driver's angle of view and therefore facilitates, to a significant extent, the driving of the vehicle.

It is also clear that the described devices 1 and 30 are is both of very simple construction and, in particular, are made so as to be highly reliable in use with time and of relatively low cost.

It is finally clear that modifications and variations can be made to the devices 1 and 30 without departing from the scope of the present invention. In particular, a different number of first blades 10 and second blades 11 can be provided and the assemblies 15 and 32 connecting the second blades 11 to the articulated quadrilateral 4 can be made differently with, for example, a different number of rods and with these connected differently to the articulated quadrilateral 4 itself, while always permitting, however, the second blade 11 to pivot 7 relative to the articulated quadrilateral 4 and, particular, relative to the first and second rods 5, 51 of the articulated quadrilateral itself.

Finally, as regards the device 30, the end 331 of the rocker bar 33 can be coupled to the second rod 5 1 by a coupling different from than that described, and made, for example, to facilitate relative movement of the end 331 of the rocker bar 33 and the second rod 51.

Furthermore, the devices 1 and 30 do not necessarily have to be used for driving wipers for wiping a particular area of the windscreen 2 but can also be used, for example, to drive blades adapted to wipe-wash headlights in applications where the size of the devices 1 and 30 themselves are comiDatible with the dimensions of the headlight surfaces to be cleaned.

12

Claims

1. A drive transmission device for wiper blades, particularly for wiper blades for a vehicle windscreen,, said device including a plurality of rods pivotally connected to each other and adapted for pivotal connection to the body of the vehicle so as to define an articulated quadrilateral able to pivot relative to said body between two extreme angular positions, said articulated quadrilateral carrying at least one first blade and at least one second blade adjacent each other, said first blade being connected to an end portion of said articulated quadrilateralr and said second blade being connected to an intermediate portion of the articulated quadrilateral itself, and connecting means interposed between said articulated quadrilateral and said second blade and fixed to said articulated quadrilateral for pivoting said second blade relative to said articulated quadrilateral itself during at least part of the pivoting of the latter between said extreme angular positions.

2.

A device according to Claim 1, wherein said articulated quadrilateral includes first and second adjacent rods arranged to be moved p 13 relative to each other, said connecting means including at least one rocker element, an intermediate portion of which is connected to said first rod for pivoting about an axis orthogonal to said first rod, and one end of which is coupled to said second rod by an interposed control element adapted to control relative movement between said rocker element and said first rod, said rocker element having its opposite end from that coupled to said second rod connected to said second blade

3. A device according to Claim 2, wherein said control element comprises a rod, one end of which is pivoted on an intermediate portion of said second rod for pivoting about an axis orthogonal to said second rod and the other end of which is pivoted on the opposite end of said rocker element from that fixed to second blade for pivoting about an axis substantially parallel to said axis orthogonal to said second rod.

4. A device according to claim 2, wherein said control element comprises a coupling adapted to allow pivoting of said end of the said rocker element opposite the end fixed to the second 14 blade relative to the second rod and about an axis orthogonal to said second rod, and a translational movement of this end itself in a direction parallel to the second rod.

5. A device according to any one of Claims 2 to 4, wherein an elastically deformable flexible element is interposed between said end of said rocker element opposite that connected to said second rod and said second blade.

6. A device according to Claim 5, wherein said flexible element is a resilient blade.

7. A drive transmission device for wiper blades, particularly f or wiper blades of a vehicle windscreen, substantially as described with reference to any of the appended drawings.

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