FR2879985A1 - Windshield wiper blade e.g. flat wiper blade, for motor vehicle, has support formed of support units set acting as wiping blade mount, where support units are articulated with each other and oriented along direction perpendicular to plane - Google Patents

Abstract

The blade has a support (5) which is constituted of a set of n support units (Vi). The units (Vi) act as a mount for wiping strip (1) and are articulated with each other. The units are oriented along a direction perpendicular to a plane. The number of the support units is determined with respect to the length of the wiping blade and to variations of radius of curvature of a surface to be wiped (S). An independent claim is also included for a motor vehicle comprising a windshield wiper blade.

Description

Wiper blade

  The present invention relates to a wiper blade whose blade optimally matches the variations of curvature of the wiped part, and which exerts an optimized pressure on the whole of its contact zone with said wiped portion.

  Indeed, the increasingly widespread use of windshields and panoramic glasses, which have continuous glazed surfaces between their frontal and lateral parts, implies that the wiper system is confronted with significant variations in curvature. scanning. However, in case of poor adaptation of the wiper of said wiper system to these bending variations, underpressure zones and overpressure zones of said broom may appear on the wiped surface: underpressure implies poor quality of the wiper. wiping and improper positioning of the wiper blade, particularly at the time of turning, when said wiper has reached one end of the surface to be wiped; an overpressure implies an accelerated aging of said blade, as well as an exacerbated noise, annoying and source of poor quality perceived for the user.

  Two types of wiper blades are known, for which different means have been put in place in order to try to optimize, at the same time, the adaptation of your blade of said wiper blade to the curvature of the surface. wiping, and the pressure exerted by said blade on said surface.

  Whatever the type considered, the wiper blade comprises, in particular, a wiper blade and a mount to ensure the connection with the support arm of said blade. The wiper blade, generally made in the form of an elastomeric profile of more or less complex shape, has a substantially longitudinal axis, and comprises a lip of appropriate shape, coming into contact with the surface to be wiped, and, substantially opposite to said lip, a base, or heel, of appropriate shape, in particular, to the connection of said blade with said mount of said blade.

  In the oldest of the wiper blade categories, as shown in FIG. 1, which is a perspective view of a cross-section of a windshield wiper blade, a blade 1, of substantially longitudinal axis X, made in the form of a profile of elastomeric material, comprises, in particular, a lip 2 coming into contact with the surface to be wiped, and on the portion substantially opposite to said lip 2, or heel 3, at least a housing 4 substantially longitudinal, intended to accommodate a vertebra 5, substantially rectilinear, whose role is to ensure a rigid retention of said blade 1 over its entire length while having sufficient elasticity to allow [adite lame 1 follow your outline of your surface to be wiped. A set of claws 7 inserted in at least one housing 6, substantially longitudinal, said heel 3, completes the maintenance of said blade 1 over its entire length and ensures the Link between said blade 1 and the pedals (not shown in Figure 1) said wiper blade.

  Such windscreen wipers are presented, in particular and in a non-exhaustive manner, by the documents US6336243 or US5463790, in which the windscreen wiper includes a greater or lesser number of lifters to the support arm of said wiper blade. , equipped with elastic connection means for distributing your support pressure along the blade of said blade to allow it to follow the curvature of your surface to be wiped.

  Such brush systems, relatively tolerant with respect to relatively large radii of curvature (it suffices to act on the number and the height of said pedals to adjust said brush to a given set of curvatures), do not, however, generally not very aerodynamic behaviors, especially when the vehicle equipped with such brushes moves with a relatively high speed (broom lifts). Another disadvantage of the rudder wiper systems is related to the large number of interstices and pivots they involve because of their design, and are frequently subject to blockages in cold weather (ice, snow. ..), making the wiper inoperative.

  The second category of wiper blades, called flat blades, is shown in Figure 2, which is a set of views of a blade of a flat wiper blade, in which Figure 2A is a general view of such a broom, and Figure 2B is a sectional view along your Il-H direction of said broom. The blade 1 of the wiper blade has a vertebra 5 which has a substantially curved shape, established, from a mean radius of curvature defined as a function of the radius of curvature most commonly encountered by the blade 1 during its scanning, so that a substantially constant pressure is applied over the entire length of said blade. The shape of said vertebra 5 further allows it, in this case, to perform the functions of the claws 7 mentioned above and to play the role of mounting of said wiper blade, said vertebra 5 being connected, by means a substantially central element 8, not detailed in Figures 2A and 2B, the support arm of said wiper blade.

  Such windscreen wipers are described, for example and without limitation, by DE10139104. It immediately appears that such brushes, if they frequently have better aerodynamic performance (limited lifting when the vehicle equipped with said brushes moves with a relatively high speed), may be relatively unsuitable for sudden variations in radius of curvature, as it is often encountered in your windshields and panoramic glasses mentioned above.

  The documents WO2004078541, WO2004054860 and WO2004054859 present, for their part, a wiper blade of the flat-blade type described above, in which two substantially rectilinear elements and behaving substantially like elongated springs, are bent along a radius of curvature less than that of the surface to be wiped and play the role of vertebrae on each of the side faces of the heel of the wiper blade. Said heel also supports a set of overmolded elements and uniformly distributed over its length. The role of frame here is played by a set of bars placed in housings of a substantially rigid longitudinal element placed substantially on the deck of your wiper blade, between said overmoulded elements previously mentioned, the assembly "bars - rigid element longitudinal "being intended to ensure the maintenance of the assembly, while maintaining said sweeper sufficient relative flexibility, due to appropriate shapes shaped to said substantially rigid element and the relative elasticity of the material used to make said substantially rigid element, for that the wiper blade can follow the curvatures of the surfaces to be wiped. Such a broom, however, still has insufficient adaptation to abrupt changes in radius of curvature of the surface to be wiped. Its implementation seems, moreover, relatively complex in view of the gains in terms of flexibility of said wiper blade and control of the pressure applied by said blade on the surface to be wiped.

  The object of the present invention is to provide a wiper blade of the flat-blade type in which the wiper blade optimally remains in contact with the surface to be wiped off and exerts on said surface an appropriate pressure, whatever or the radius of curvature encountered by said wiper blade during scanning.

  The invention achieves its goal by means of a wiper blade comprising a wiper blade, having a lip intended to come into contact with a surface to be wiped and a heel substantially opposite to said lip, comprising less a vertebra which is oriented along the median plane of the blade and which is connected to a connecting element for reattaching said wiper blade to a support arm which can communicate to said wiper blade a sweeping movement of the blade; surface, characterized in that said vertebra is constituted by a finite number n of vertebral elements.

  Advantageously, said vertebral elements are articulated to each other by means of axes perpendicular to the median plane of the blade.

  In a preferred embodiment of the invention, a spring is inserted between each of said vertebral elements and its contiguous vertebral element.

  Advantageously, the invention may also have one or more of the following features; each of said vertebral elements is pivotally articulated to each of the vertebral elements which are contiguous to it on either side, the number of said vertebral elements is defined as a function of the area and the curvature of said surface to be wiped, - said vertebral elements located at the ends of said wiper blade have a shape suitable for holding the blade of said blade in a direction parallel to the median plane.

  said substantially central element has a shape suitable for its articulated connection with the vertebral elements which are contiguous to it on either side, according to a principle substantially similar to that of the articulation of said vertebral elements with one another, said springs being arranged with such that they rest on one of said vertebral elements and refer to their pressure relative to the immediately adjacent vertebral element, said springs are torsion springs, one end of which bears on said vertebral element, and the other end takes resting on its contiguous vertebral element so as to exert a return moment on said adjacent vertebral element, said springs are lamellar, said springs have identical stiffnesses over the entire length of said wiper blade, the stiffness of said springs are adjusted along said wiper blade according to the curvature of the surface at e ssuyer, said vertebral elements and said springs are made in one piece, the dimensions of said vertebral elements are identical over the entire length of the wiper blade according to the invention, - the dimensions of said vertebral elements are not identical over the entire length of said brush and may, in particular, be reduced in areas where the curvature of the surface to be wiped varies significantly.

  Other features and advantages of the invention will emerge on reading the description which follows, with reference to the appended figures in which: FIG. 1 is a perspective view of a cross-section of a blade of a broom Fig. 2 is a set of views of a blade of a flat windscreen wiper, in which Fig. 2A is a general view of such a broom, and Fig. 2B FIG. 3 is a partial schematic side view of an embodiment of a windscreen wiper blade according to the invention, FIG. 4 is a sectional view along the direction II-II of said blade. Figure 5 is a cross-sectional view along a plane perpendicular to the median plane of the wiper blade, of an embodiment of a wiper blade of Figure 3; of said spinal elements according to the invention, FIG. 6 is a view from above of the central element intended to connect a Wiper blade according to the invention at its support arm, Figure 7 is a set of views in which Figure 7A is a side view of a blade according to another embodiment of the invention and Figure 7B is a top view of the blade of Figure 7A.

  As shown in Figure 3, a wiper blade has a blade 1 provided with a heel 3 and a lip 2 for wiping a curved surface S.

  In order to facilitate the description of the invention, FIG. 5 shows the wiper blade shown in a theoretical position in which the lip 2 is not bent. We then define a median reference plane P of the blade 1 passing, at each point of contact pi of the lip 2 with the surface S, by a normal Ni at the surface S. The blade also comprises a vertebra 5 consisting of a set of n vertebral elements V. These vertebral elements, whose shape, which will be detailed later, also allows them to play, locally, the mounting role of the wiper blade 1, are articulated between them via Yi axes, oriented in a direction perpendicular to the plane P. The number n of vertebral elements Vi is determined as a function of the length of the blade 1 of the wiper blade and as a function of variations in radius of curvature of the surface To wipe S. As a non-limiting example, a broom of about five hundred ro millimeters in length will have about thirty vertebral elements Vi. By convention, the vertebral elements Vi are, moreover, numbered from an element 8 which in the embodiment described is substantially central, intended to ensure the connection of said blade with its support arm (not shown in your figures) : The vertebral elements Vi are thus divided into two sub-assemblies, respectively of n 'and n "vertebral elements Vi, each located on one side of said substantially central element 8, and the element Vi + 1 is thus the contiguous element. to the element Vi, placed towards one end of said wiper blade with respect to said element Vi.

  Figures 4 and 5 show in more detail some of said vertebral elements Vi and their mode of articulation. The vertebral elements Vi have the general shape of a U whose plane is oriented in a plane perpendicular to the normal Ni at the surface, the branches of the U extending in a direction parallel to the plane P, the space formed between the branches being directed towards the central element 8 of the broom. The base of the U has a male appendix 9. The branches of the U and the appendix 9 are respectively crossed by an orifice 10a and an orifice 10b able to receive an axis Yi.

  The element Vi comprises means for holding the blade 1. For example, the element Vi comprises two tabs extending on either side of the plane P and able to cooperate each with a groove 4, parallel to the median plane. P, formed in a flank 3a of the heel 3. Said vertebral element Vi thus plays the role of your mount described above.

  During the assembly of said vertebral element Vi with the vertebral elements Vi-1 and Vi + 1 contiguous respectively on either side of said vertebral element Vi, said appendix 9 of said vertebral element Vi cooperates with the space formed between the branches the U of said vertebral element Vi + 1, and the space formed between the branches of the U of said vertebral element Vi cooperates with said appendage 9 of said vertebral element Vi-1, so that the orifices 10a and 10b are coaxial, the axes Yi and Yi-1 joining said vertebral elements Vi-1, Vi, and Vi + 1 while maintaining a pivotal connection between them. Thus, gradually, a fully articulated structure of the wiper blade according to the invention, according to a principle similar to that of a vertebral cotton.

  The end vertebral elements Vn 'and Vn ", placed at each end of the brush, have, for their part, at their end not linked to a vertebral element, ro a form suitable for maintaining your blade in a direction parallel to the plane median P, such as for example, a tab cooperating with one end of the blade.

  On the other hand, as shown in Figure 6, the substantially central element 8 has at each of its ends, an appendix 9 identical to said appendices 9 of each of said vertebral elements Vi. In the same way as for the appendices 9 of each vertebral element Vi, the appendages 9 of the central element 8 are traversed by an axis Y0, thus allowing the articulation, on either side of said substantially central element 8, of first two vertebral elements V1, and thus, step by step, two subsets of vertebral elements Vi.

  Said substantially central element 8 further comprises, in a substantially central position, an element 11 inserted in a direction substantially perpendicular to the plane P, said element 11 being intended for the connection, by appropriate means not detailed herein, of said brush according to the invention with his support arm.

  The mounting direction of the vertebral elements Vi, in the embodiment described, is inverted elsewhere on the central element 8.

  In a preferred embodiment of the invention, there is further provided spring connection elements between the vertebral elements. For example, a torsion spring Ri, having turns wound around the axis Yi, is inserted between the vertebral element Vi and the vertebral element Vi + 1. The spring Ri is in flexion and has two ends, one in contact with the vertebral element Vi and the other with the vertebral element Vi + 1.

  Thus, confronted with the local radius of curvature r, of the surface element Si to be wiped, the vertebral element Vi, rotatable, both around its axis Yi, and around the axis Yi-1 of the immediately adjacent vertebral element Vi-1 takes a position in which the element of the wiper blade 1 held by said vertebral element Vi best conforms to said surface element Si. At the same time, said spring R 1, resting on the vertebral element Vi, exerts a plating moment Mi on said adjacent vertebral element Vi + 1, thus inducing a pressure of the element of said blade 1 on the wiping surface element Si + 1 corresponding to said element vertebral Vi + 1.

  In order to conform to the broom a suitable curvature, said plating moments Mi must be applied in directly opposite directions on each side of the substantially central element 8: to do this, the mounting directions of said springs Ri are reversed on each side of said substantially central element 8, as shown in Figure 6, the mounting directions of the first springs RO placed between said substantially central element 8 and each of said first vertebral elements V1, so as to exert their pressure on said vertebral elements V1.

  A wiper blade is thus obtained in which the blade no longer has, as is the case for the brushes or flat brushes known in the state of the art, an overall behavior with respect to the wiper blade. surface to be wiped, but wherein said blade has a sum of local behaviors with respect to said surface. The discretization thus achieved of the vertebra (each of the vertebral elements Vi also plays, as has been previously described, the local role of mounting) and pressure elements on the wiping blade of the wiper blade. Thus, ice can both maintain said blade in contact with the surface to be wiped with appropriate pressure over the entire scanning surface, as well as optimally match the variations of curvature of said surface.

  In another embodiment of the invention, said springs Ri are lamellar type springs made integral with said vertebral element Vi (for example by welding) and exerting their restoring force on said adjacent vertebral element Vi-1.

  It should be noted that said vertebral elements Vi and springs Ri may be 30 indifferently made of metal materials, plastics, or composites.

  Likewise, in the embodiments presented, the functions of vertebral element Vi and of spring Ri are filled by distinct elements: in an alternative embodiment, represented in FIG. 7, these two functions can be fulfilled by a single element VRi carried out by any suitable technical means in one or more metallic, plastic or composite materials.

  It should also be noted that, in the embodiments presented by the figures, said vertebral elements Vi all have substantially the same dimension in the direction parallel to the median plane P of the blade 1, and said springs Ri are substantially all identical (in in particular, they all have substantially the same stiffness). In a variant of these embodiments, vertebral elements Vi of different dimensions may be associated, so as, for example, to increase the number of said vertebral elements Vi in the parts of the blade brought into contact with surface elements. If having strong variations of radius of curvature, and conversely, to reduce the number of said vertebral elements Vi in the parts of said blade brought into contact with Si surface elements having small variations in radius of curvature.

  Similarly, in another variant, the stiffness of the various springs R 1 can vary along the wiper blade, so as to allow an optimal adjustment of the pressure exerted by the blade of said broom on the entire surface. to wipe.

Claims (21)

claims   A wiper blade having a center plane wiper blade (1) having a lip (2) for engaging a wiping surface (5) and a bead ( 3), substantially opposite said lip (2), having at least one vertebra (5) which is oriented in the plane (P) and which is connected to a connecting element (8) for reattaching said wiper blade ( 1) a support arm capable of communicating with said wiper blade a scanning movement of the ro surface (S), characterized in that said vertebra (5) consists of a finite number n of vertebral elements ( vi).   2. Wiper blade according to claim 1, characterized in that said vertebral elements (Vi) are articulated to each other by means of axes (Yi) perpendicular to the median plane (P) of the blade (1).   3. Wiper blade according to claim 1 or 2, characterized in that each vertebral element (Vi) has the general shape of a U whose plane is oriented along a plane perpendicular to a normal (Ni) on the surface (5), the legs of the U extending in a direction parallel to the median plane (P) and the base of the U having an appendage mast (9) intended to cooperate with the space between the branches of the U of the contiguous vertebral element (Vi-1), the branches of the U of the element (Vi) and the male appendage (9) of the element (Vi- 1) being traversed respectively by an orifice (10a) and a coaxial aperture (10b) for receiving the axis (Yi-1).   4. Wiper blade according to the preceding claim, characterized in that the mounting direction of the vertebral elements (Vi) is reversed on either side of the element (8).   A wiper blade according to any one of claims 1 to 4, characterized in that each of said vertebral elements (Vi) is thus pivotally connected to the adjacent vertebral elements (Vi + 1) and (Vi-1). ).   6. Wiper blade according to any one of claims 1 to 5, characterized in that the number n of vertebral elements (Vi) is defined according to the area and the curvature of said surface (S ) to wipe.   A wiper blade according to any one of claims 1 to 6, characterized in that said element (8) has a shape suitable for its articulated connection with said vertebral elements (V1) which are contiguous to it, according to the the same principle as that of articulated links of said vertebral elements (Vi) to each other.   ro 8. Wiper blade according to any one of claims 1 to 7, characterized in that said terminal vertebral elements (Vn ') and (Vn "), respectively placed at both ends of said wiper blade, have an appropriate shape, at their end not connected to an adjacent vertebral element, the maintenance of said blade (1) in a direction parallel to the plane (P).   9. Wiper blade according to any one of claims 1 to 8, characterized in that a spring (Ri) is inserted between each of said vertebral elements (Vi) and its contiguous vertebral element (Vi + 1). .   10. Wiper blade according to any one of claims 1 to 9, characterized in that a spring (Ri) is arranged between said substantially central element (8) and each of said adjacent vertebral elements (V1) from and other.   11. Wiper blade according to any one of claims 9 or 10, characterized in that said spring (Ri) is a torsion spring, whose turns are wound around the axis (Yi) and one of which end is supported on said vertebral element (Vi), and the other end is supported on the vertebral element (Vi + 1) so as to exert a moment of return on said vertebral element (Vi + 1).   12. Wiper blade according to any one of claims 9 or 10, characterized in that said spring (Ri) is a lamellar spring integral with said vertebral element (Vi), and exerts a moment of return on said vertebral element. contiguous (Vi-1).   13. Wiper blade according to any one of claims 8 to 12, characterized in that the mounting direction of the springs (Ri) is reversed on either side of the element (8).   14. Wiper blade according to any one of claims 1 to 13, characterized in that the dimensions of said vertebral elements (Vi) in a direction parallel to the median plane (P) are substantially identical.   A wiper blade according to any one of claims 1 to 13, characterized in that the dimensions of said vertebral elements (Vi) in a direction parallel to the median plane (P) are substantially different.   16. Wiper blade according to the preceding claim, characterized in that said vertebral elements (Vi), the dimension of which is smaller, are placed in areas of said broom caused to wipe elements of the surface (S) having the larger variations in radius of curvature.   17. Wiper blade according to any one of claims 9 to 16, characterized in that the stiffness of said springs (Ri) are all identical.   Windscreen wiper blade according to one of Claims 9 to 16, characterized in that the spring stiffness (Ri) is adjusted as a function of the pressure to be exerted by the part of said blade (1) held by said vertebral element (Vi) and said spring (Ri) on said surface element (Si) to be wiped.   Windscreen wiper blade according to one of Claims 9 to 16, characterized in that the vertebral element (Vi) and spring (Ri) functions are fulfilled by a single element (VRi). 20. Wiper blade according to any one of claims 9 to 19, characterized in that said vertebral elements (Vi), springs (Ri), or single elements (VRi), are made of plastic or composite materials.   21. A motor vehicle equipped with wiper blades according to any one of claims 1 to 20.