FR2581946A1 - Windscreen wiper device, particularly with several blades, comprising, for at least one blade, a non-circular wiping system - Google Patents

Abstract

The windscreen wiper device comprises a non-circular wiping system which comprises a main arm moved by a driveshaft 5, this arm carrying a rocker which carries the windscreen wiper blade, and an auxiliary arm, one end of which is articulated to the rocker and the other end of which is articulated to a pivot 11 which is radially offset with respect to the rotational axis 0 of the main arm. The pivot 11 is itself driven with an alternating oscillatory movement about the axis of rotation 0 of the main arm. The alternating oscillatory movement of the pivot 11 is phase-shifted with respect to that of the main arm. The two alternating oscillatory movements of the main arm and of the articulation pivot 11 have substantially the same angular amplitude and are phase-shifted by an angle such that when the main arm occupies a limiting angular position and is going to move in one direction, the pivot 11 occupies another limiting position and is going to move in the opposite direction.

Description

WIPER DEVICE, PARTICULARLY WITH MULTIPLE BRUSHES,
COMPRISING, FOR AT LEAST ONE BROOM, A SCANNING SYSTEM
NOT CIRCULAR.

 The invention relates to a wiper device, in particular to several brushes, comprising, for at least one brush, a non-circular sweeping system.

 The wiper devices covered by the invention are of the type in which the non-circular wiper system comprises - on the one hand, a main arm moved by a drive shaft in an oscillating movement alternative around an axis of rotation, this main arm carrying, at its end remote from the axis of rotation, a rocker arm articulated around a transverse axis, substantially parallel to the sweeping surface, this rocker arm carrying the brush windscreen wiper itself articulated around a second transverse axis substantially parallel to the first, - on the other hand, an auxiliary arm, one end of which is articulated on the rocker arm, and the other end of which is articulated on a pivot offset radially from to the axis of rotation of the main arm, this pivot itself being driven in an alternating oscillation movement around the axis of rotation of the main arm, the alternative oscillation movement of the pivot being out of phase with that of the main arm, the auxiliary arm making it possible to control movements of the rocker arm which cause a displacement of the wiper blade in a direction substantially parallel to its longitudinal direction.

 The object of the invention is, above all, to provide a wiper device of the kind in question which, while ensuring an increase in the swept area thanks to the non-circular sweeping system, leads to a relatively simple trajectory of the blade.

According to the invention, the device is an agency
te that the two alternative swing movements of the arm
main and Mu articulation pivot of the auxiliary arm have
substantially the same angular amplitude and are out of phase
angularly at an angle such as when the main arm
occupies an extreme angular position, and will move in one direction, the pivot occupies another extreme position and will
move in the opposite direction.

The main arm and the pivot pass substantially
simultaneously in an average position located, angularly, equidistant from the extreme positions
With such a device, while obtaining an increase in the swept area, the brush is made to accomplish, during its outward movement, a trajectory close to or coincident with that which it performs during its return movement.

 The wiper device comprises a first device capable of transforming the continuous rotational movement of a motor shaft into an alternative oscillating movement of the drive shaft, this movement transforming device comprising a crank wedged on the motor shaft and a rod articulated at one end of this handle, the other end of the rod being connected to the drive shafts, and a second device for transforming the movement of continuous rotation of the motor shaft in an alternative oscillating movement of the pivot, this second device comprising a rod linked, at one end, to the pivot and, at its other end, to an articulation point secured to the crank ~ - ------------ the wiper device according to the invention, is characterized in that the articulation point of the rod of the second movement transformation device is angularly offset about 1800 from the point of articulation between the man ivelle and the stem of the first device.

 The two devices for transforming the movement of continuous rotation into an alternative oscillation are arranged in such a way that the movements of the main arm and of the pivot have substantially the same angular amplitude, in particular close to 90-.

 Preferably, the point of articulation of the rod of the second movement transformation device is diametrically opposite the point of articulation of the rod of the first device, relative to the axis of the motor shaft.

 In the case of a bibalai wiper device, the arm carrying the second blade is driven in an alternative oscillating movement by an articulated rod, at one end, on the crank wedged on the motor shaft.

The joints of the two rods on the crank can be superimposed and mounted on an axis integral with the crank, parallel to the motor shaft; a part integral with this axis and the crank is provided on the side of the articulations opposite to said crank; this part extends parallel to the radial direction of the crank, orthogonally to the axis of the drive shaft; said part carries an axis diametrically opposite to that of said articulations, relative to the motor shaft, this axis being intended for the articulation of the rod controlling the alternating oscillation of the pivot of the auxiliary arm.

 The control of alternative oscillation movements, from each rod, can be ensured by a crank whose articulation point on the end of the rod is offset radially with respect to the axis of oscillation of the shaft drive or pivot.

 The invention consists, apart from the arrangements set out above, of a certain number of other arrangements, which will be more explicitly discussed below in connection with a particular embodiment described with reference to the attached drawings. , but which is in no way limiting.

 Figure 1 of these drawings is an elevational view, with parts broken away, of the devices for transforming the continuous rotation movement into an alternating oscillation movement for a two-blade wiper device according to the invention.

 FIG. 2 is a plan view in relation to FIG. 1.

 Figure 3 is a schematic side view of a main wiper arm equipped with a rocker arm and the associated auxiliary arm.

 FIG. 4 is a diagram of the wiping zones obtained with a bi-wiper device according to the invention.

 FIG. 5, finally, is a diagram illustrating the offset of the alternating oscillation movements of the main arm and of the articulation pivot of the auxiliary arm.

 Referring to the drawings, in particular to Figures 1 to 3, we can see a wiper device 1 of the two-blade type, comprising, for a blade 2 (Figure 3) at least, a non-circular scanning system 3 .

 This system 3 comprises, on the one hand, a main arm 4 moved by a drive shaft 5 according to an alternative oscillating movement around an axis of rotation O formed by the geometric axis of the shaft 5. The main arm 4 carries, at its end remote from the axis 0, a rocker arm 6 articulated around a transverse axis 7 substantially parallel to the scanning surface. This rocker arm 6 carries the brush 2 itself articulated around a second transverse axis 8 substantially parallel to the first.

 The system 3 comprises, on the other hand, an auxiliary arm 9, one end of which is articulated on the rocker arm 6 at a point 10, generally situated between the axes 7 and 8.

 The other end of the arm 9 is articulated on a pivot 11 offset radially with respect to the axis O as visible in FIG. 1. The pivot 11 can be produced in the form of a spherical ball joint. The pivot 11 is itself driven in an alternating rotational movement around the axis O of rotation of the main arm.

 The alternative rotational movement of the pivot 11 is out of phase with that of the main arm 4. The auxiliary arm 9 makes it possible to control movements of the rocker arm, which rotates around the axis 7, causing the wiper blade to move. ice 2 in a direction substantially parallel to its longitudinal direction.

 The second wiper blade 12 (FIG. 4) is driven in an alternating oscillating movement by a second drive shaft 14.

 As shown in FIG. 1, the shafts 5 and 14 can be rotatably mounted in respective bearings 15, 16 fixed on the same plate 17. The bearing 15 can be formed by a kind of cylindrical sleeve comprising a flange 18 bearing against one face of the plate 17; a part 19, externally threaded, of the sleeve 15, passes through a hole 20 provided in the plate 17; a nut, not shown, can be screwed onto this part 19 to block the bearing 15 on the plate 17. The bearing 16 can be arranged in a similar manner. The shafts 5 and 14 completely pass through their bearing 15 and 16. The shafts 5 and 14 are advantageously provided at their ends intended to be connected to the wiper arm, with a shoulder. # Conical section Sa, fluted 14a .

 The end 5b, 14b of the shafts 5 and 14, remote from the arm associated with each shaft, is locked in rotation on an elongated flat part 20, 21 constituting a kind of crank. The ends 5b, 14b can be constituted by an extension having two parallel flat faces suitable for coming to cooperate with two rectilinear edges of an oblong opening provided in each part 20, 21.

 The wiper device 1 comprises a first device T1 capable of transforming the continuous rotational movement of a motor shaft 22 into an alternative oscillating movement of the drive shaft 5 and the drive shaft 14. The shaft 22 is driven, for example, by an electric motor 23 via a reduction gear 24.

 The movement transformation device T1 comprises a crank 25 wedged on the motor shaft 22. This handle 25, as visible in FIG. 1, can be bent back so that its end radially distant from the shaft 22 is offset, along the longitudinal direction of this axis, beyond the end of the shaft.

 The device T1 comprises a first rod 26 constituting a sort of connecting rod, articulated on the end of the crank 25 radially distant from the shaft 22; more specifically, an axis 27, parallel to the axis 22, is made integral with said end of the crank 25; the rod 26 is provided, at its end, with a head 28 comprising a bore in which the axis 27 is engaged to ensure the articulation.

 The other end 29 of the rod 26 is linked to the drive shaft 5 by means of the part 20.

More precisely, this end 29 is equipped with a pin 30 on which the end of the part 20 is articulated radially distant from the axis 5.

 The device T1 is arranged in a similar manner to ensure the transformation of the continuous movement of the shaft 22 into an alternative oscillation movement of the shaft 14. A rod 31, constituting a kind of connecting rod, is articulated on the end of the crank 25; for this, the rod 31 has, at its end, a head 32, similar to the head 28, comprising a bore in which the axis 27 is engaged. At its other end, the rod 31 is connected by an articulation 31b to the end of the part 21 radially distant from the shaft 14. According to the embodiment of Figure 1, the two rods 26, 31 are located in two parallel planes offset in the direction of the axis 27, the rod 31 being located on the side of the rod 26 opposite the shaft 22.

 It is immediately understood, as can be seen from FIG. 2, that the continuous rotational movement of the shaft 22 and of the crank 25 is transformed into an alternative oscillating movement of the parts 20 and 21 and of the shafts 5 and 14, around the geometric axes of these trees.

 The angular amplitude of the movement of the part 20 and therefore of the oscillation of the shaft 5 is designated by A in FIG. 2.

 The articulation pivot 11 is driven in an alternating oscillation movement around the axis O having an amplitude equal to or substantially equal to A. The movement of the pivot 11 is out of phase with that of the arm 4 by an angle such that, when the main arm 4 leaves from an extreme angular position, the pivot 11 is substantially on another opposite extreme angular position, and leaves in the opposite direction.

goes in the opposite direction.

 FIG. 2 illustrates the position of the various elements of the device in an extreme position. The part 20 and therefore the shaft 5 as well as the main arm 4 (not shown in FIG. 2) linked to this shaft 5, begin their movement in the direction of the arrow F1 around the axis 0, that is i.e. clockwise. The pivot 11 which is also in an extreme angular position leaves in the other direction, along the arrow F2, that is to say in the anti-clockwise direction around the axis 0.

 A second device T2 (FIG. 1) for transforming the continuous rotation movement of the motor shaft 22 into an alternative oscillation movement of the pivot 11 is provided. This second device T2 comprises a rod 33, also constituting a kind of connecting rod, linked at one end 34 to the pivot 11 by means of connection means L. These connection means comprise a flat part 35 similar to part 20 constituting a kind of crank or lever, one end of which is articulated on the end 34 of the rod 33. The distance dl (fig 2) between the axis O and the articulation of the part 35 on the end 34 is equal to the distance d2 (fig. 2) between the axis O and the articulation of the part 20 on the end 29. The part 35 has, at its other end, an opening 36 coaxial with the shaft 5, in which is engaged a cylindrical hollow shaft 37 coaxial with the shaft 5. The part 35 is locked in rotation on the shaft 37, which is mounted free in rotation relative to the bearing 15. The shaft 5, which passes through the hollow shaft 37 , is free to rotate relative to the latter. The connection in rotation of the part 35 and the shaft 37 can be ensured by the cooperation of two diametrically opposite flats, provided on the outer surface of the shaft 37 with two straight edges. of the --- opening 36. The part 35 can be # held, with a freedom in rotation, against the bottom of the bearing 15 by a nut 38 screwed onto an externally threaded part of the shaft 37. The axial stop of the shaft 37 relative to the bearing 15 can be ensured by means of a split rod 39 anchored in a groove provided at the periphery of the shaft 37, this rod 39 being able to cooperate with the transverse end face of the bearing 15 opposite to part 35. The pivot is fixed on a flat part 40, forming a crank, extending radially with respect to the shaft 5. This part 40 comprises, at its end opposite to pivot 11, a window 41, traversed by the end of the shaft 37 opposite the part 35. The part 40 is linked in rotation to the shaft 37, for example by the cooperation of two straight parallel edges of the window 41 with two flats provided on the end of the axis 37. The axial retention of the part 40 is ensured by a nut 42 screwed on the external threaded end. ent of the tree 37.

The shaft 5 can be stopped axially with respect to the shaft 37 by a split rod, anchored in the shaft 5, or by any equivalent means.

 The rod 33 is linked, at its other end 43, to a point of articulation 44 secured to the crank 25.

 This articulation point 44, as clearly visible in FIG. 2, is angularly offset by 1800 or around 1800 relative to the articulation point, located on the axis 27, between the crank 25 and the rod 26 of the device T7 for driving the shaft 5. It should be noted that the axis 27 also constitutes the articulation point for the other rod 31 for driving the shaft 14.

 Preferably, the articulation point 44 is formed by an axis or equivalent member) carried by a part 45, for example in the form of a racket, extending parallel to the radial direction of the crank handle 25. The axis 44 is diametrically opposite the axis 27 with respect to the axis of the shaft 22, but is located on the side of the part 45 opposite that of the axis 27. The distance hi (FIG. 2) from the axis 44 to l The geometric axis of the shaft 22 is therefore equal to the distance h2 from the axis 27 to the geometric axis of the shaft 22. The rod 33 is arranged at a level higher than that of the rod 31 when the 'we are looking at Figure 1. part 45 is itself arranged above the rods 26 and 31, still according to the representation of Figure 1. Part 45 is integral with the axis 27 and therefore the crank 25. The assembly of the part 45 and of the crank 25 connected by the axis 27, and of the axis 44 constitutes a kind of crankshaft with two crankpins.

 This being the case, the operation of the two-blade wiper device according to the invention is as follows. We will consider, essen tie ~ lement, for the explanations that follow, Figures 2 to 5.

 The assumed starting position is that of FIG. 2 for which the part 20 occupies an extreme position corresponding to the extreme angular position 4b (FIGS. 4 and 5) of the main arm 4. The other arm 13 also occupies an extreme position 13b ( figure 4). The two positions, in the example considered, are low positions on the windshield.

 The pivot 11 occupies the extreme angular position 11b schematically represented in FIG. 5.

 The shaft 22 is driven in a continuous rotation movement in a clockwise direction according to the representation of FIG. 2. The parts 20 and 21 will move, from their extreme angular position represented in FIG. 2 , by turning clockwise (arrow F1) around the geometric axes of the respective trees 5 and 14.

 On the other hand, the part 35, driven by the axis 44, diametrically opposite the axis 27, will rotate in the sen! counterclockwise around axis 0. Pivot 11 will therefore move from its extreme position 11b (Figure 5) by turning anti-clockwise around axis O - (arrow F2, figures 2 and 5).

 As a result, the angular difference between the main arm 4 and the radius passing through the axis O and the pivot 11 will decrease. The auxiliary arm 9 will therefore push the axis 10 outward and move the brush 2 radially outward. The trajectory of the outer radial end of the brush 2 is represented by the curve 46 in FIG. 4 which goes beyond the circular trajectory 47; the trajectory of the inner radial end of the brush 2 is represented by the curve 48 in this same figure 4 and also goes beyond the circular trajectory 49. It appears however that the surface swept is greater than in the case of a circular sweep, this increase in swept area corresponding to the difference between the areas limited by curves 46 and 47 (increase in surface) and curves 48, 49 (smaller decrease in surface).

The brush 2 is pushed out as far as possible when the pivot 11 crosses the arm 4.

 When this arm 4 reaches its other extreme angular position 4a (FIG. 5) the pivot 11 also reaches its other extreme angular position 11a, since the angular amplitude A of the alternating oscillation of the pivot 11 is equal or substantially equal to that of the arm 4. During the return movement, the ends of the wiper blade will describe the same trajectories 46, 48 as during the forward movement.

 The polar radius Dm passing through the point of the path 46 furthest from the axis O has an angular position which corresponds to the intersection of the pivot 11 and the arm 4.

 The two extreme positions 11a and 1b of the pivot 11 can have the same angular positions as the positions ex thrones 4b and 4a of the arm; the radius Dm is then merged with the bisector of the angle formed by the extreme positions 4a. 4b of the main arm.

 The other brush 12 describes a circular trajectory around the geometric axis of its shaft 14.

 Generally, the brush 2 with a non-circular path, which makes it possible to obtain an increase in the swept area, is provided opposite the seat of the driver of the vehicle.

 The other brush 12 could, if necessary, also be driven in a non-circular sweeping movement using a rocker and auxiliary arm system similar to that of FIG. 3. The auxiliary arm would be entrained by a pivot, similar to pivot 11, moved in an alternating oscillation movement around the geometric axis of the shaft 14. The entrainment of this other pivot could be ensured by the device T2 completed by a rod and a similar part to the rod 33 and to the part 35 used for driving the pivot 11.

Claims (6)

 1. Wiper device, in particular with several blades, comprising, for at least one blade, a non-circular sweeping system comprising - on the one hand, a main arm moved by a drive shaft in a movement d alternative oscillation around an axis of rotation, this main arm carrying, at its end remote from the axis of rotation, a rocker articulated around a transverse axis, substantially parallel to the sweeping surface, this rocker bearing the brush wiper itself articulated around a second transverse axis substantially parallel to the first, - on the other hand, an auxiliary arm whose one end is articulated on the rocker arm, and whose other end is articulated on a pivot offset radially relative to the axis of rotation of the main arm, this pivot being itself born in an alternating oscillation movement around the axis of rotation of the main arm, the alternative oscillation movement of the pivot being out of phase with respect to to that of the main arm, the auxiliary arm making it possible to control movements of the rocker arm which cause a displacement of the wiper blade in a direction substantially parallel to its longitudinal direction, this wiper device comprising a first device (T1 ) suitable for transforming the continuous rotation movement of a motor shaft (22) into an alternating oscillation movement of the drive shaft (5), this movement transformation device comprising a crank 125) wedged on the motor shaft (22) and a rod (26) articulated at one end of this crank, the other end (29) of the rod being linked to the drive shaft (5), and a second device (T2) for transformation of the continuous rotational movement of the motor shaft (22) into an alternative oscillating movement of the pivot (11), this second device (T2) comprising a rod (33) linked, at one end (34), to the pivot (ll) and, at its other end (43tu at a point of articulation (44) integral with the crank (25), characterized in that the articulation point (44) of the rod (33) of the second movement transformation device (T2) is angularly offset by about 1800 relative to the point of articulation (27) between the crank (25) and the rod of the first device (T1).  2. Device according to claim 1, characterized in that the articulation point (44) of the rod (33) of the second movement transformation device (T2) is diametrically opposite to the articulation point (27) of the rod (26) of the first device, relative to the axis of the motor shaft (22).  3. Device according to any one of the preceding claims, characterized in that the extreme positions (11a), 11b) of the pivot (11) have the same angular positions as the extreme positions (4b, 4a) of the main arm (4 ).  4. Device according to any one of claims 1 to 3, characterized in that the end (29) of the rod (26) of the first device (T1) is linked to the drive shaft (5) by through a part (20) constituting a kind of crank while the rod (33) of the second device (T2) is connected, at one end (34) to the pivot (11) via a part (35) also constituting a kind of crank, the distance (dl) between the axis (0) of the drive shaft (5) and the articulation of the part (35) on the end (34), of the rod of the second device (T2), being equal to the distance (d2) between the axis (O) and the articulation of the part (20) on the end (29) of the rod (26) of the first device.  5. Device according to any one of the preceding claims, characterized in that a part (45) integral with the crank (25) extends parallel to the radial direction of this crank, orthogonally to the axis of the motor shaft (22), said part (45) carrying an axis (44) diametrically opposite to that of the articulation (27) of the rod (e6) of the first device (T1) on the crank (25), this axis ( 44) being intended for the articulation of the rod (33) controlling the alternating oscillation of the pivot (11) of the auxiliary arm.  6. Bi-brush windscreen wiper device according to claim 5, in which the arm (13) carrying the second blade is driven in an alternating oscillation movement by a rod (31) articulated, at one end, on the crank (25) wedged on the motor shaft (22), characterized in that the articulations (28, 32) of the rods (26, 31) on the crank are superimposed and mounted on an axis (27) integral with the crank, the aforesaid part (45) being integral with this axis (27) and being provided on the side of the joints (28, 32) opposite to said crank (25).