WO2009016205A1

WO2009016205A1 - Wiper blade for windscreen wiper and method of manufacturing such a blade

Info

Publication number: WO2009016205A1
Application number: PCT/EP2008/060002
Authority: WO
Inventors: Jean-Michel Granes; Gilles Petitet; Severin Doupeux
Original assignee: Valeo Systemes D'essuyage
Priority date: 2007-07-30
Filing date: 2008-07-30
Publication date: 2009-02-05
Also published as: FR2919552B1; FR2919552A1

Abstract

The present invention relates to a wiper blade 10 for a windscreen wiper 1, comprising a heel 11 and a lip 12 which are connected to one another by a portion of smaller cross section that forms a hinge 13. The invention is notable in that the lip 12 has a width substantially identical to that of the heel 11.

Description

WIPER BLADE FOR WIPER BLADE AND METHOD FOR MANUFACTURING SUCH BLADE

The present invention relates to a wiper blade for equipping a wiper blade.

The invention also relates to a method for manufacturing such a blade.

The invention finds a particularly advantageous application, but not exclusive, in the field of flat brushes commonly referred to by Anglicism flat blades.

A wiper blade is schematically constituted by a wiper blade of flexible material, which is supported by an elastically deformable structure. In general, the wiper blade is in the form of a profile comprising a heel integral with the support structure, a lip whose free end is intended to cooperate by sliding contact with any surface to be wiped, as well as a intermediate part connecting the lip to the heel in an articulated manner. The heel is the most massive part of the blade as its role is to interface with the support structure of the blade. The lip corresponds to the part of the blade which is responsible for performing the wiping function, and that is why it logically has a much sharper shape than the heel. Finally, the intermediate portion is usually constituted by a blade portion of lesser section, forming a hinge.

We also know that to obtain a maximum wiping quality, it is essential that the inclination of the free end of the lip, relative to the surface to be wiped, is maintained in the vicinity of an optimum value. given. This is why the assembly is conventionally arranged so that the lifter comes to wedge systematically against the heel or support structure when the blade is moved laterally in contact with the surface. The wedging takes place alternately on one side or the other of the blade according to the direction of effective movement of the blade; the inversion of the scanning direction imposing a reversal of the wiper blade, that is to say a tilting of the lip of a position of stall to another.

In order to facilitate this wedging phenomenon, the lip is traditionally provided with shoulder-shaped stops on each of its main faces; each stop bearing against the heel of the blade, or against the support structure of the blade, depending on the direction of movement of the blade. In practice, and even if the presence of these two shoulders inevitably tends to widen it somewhat, the lip still has a width less than that of the heel. This is explained by the fact that the lip is a moving mass that should be reduced to the maximum so as not to increase the inertia of the blade.

[0007] However, this type of blade profile has the disadvantage of being relatively difficult to achieve. It is indeed usually manufactured by extrusion and crosslinking of an elastomeric profile; the extrusion in question operates flat on a horizontal support surface. Or because of the difference in width between the two articulated parts of the blade, only the heel will rest on the support surface while the lip will not be supported in any case. The latter will therefore fully undergo the action of gravity, and especially as it constitutes a significant mass. The lip and the hinge will then tend to deform as extrusion, thus generating geometry defects that will be frozen during crosslinking. In the end, this will lead to the use, a deterioration of the quality of wiping, and to manufacturing, an increase in the rate of rejects with the ultimate consequence of a significant increase in the cost price of the blade.

Also, the technical problem to be solved by the object of the present invention is to provide a wiping blade for a wiper blade, comprising a heel and a lip connected together by a portion of lesser section forming hinge, wiper blade that would avoid the problems of the prior art being notably significantly less expensive to manufacture, while ensuring excellent quality wiping.

The solution to the technical problem consists, according to the present invention, in that the lip has a substantially identical width. to that of the heel.

It is important to emphasize that the invention is applicable to any type of wiper blade, whether it is a conventional broom or a new generation flat broom. It is also understood that apart from the width parameter, the invention does not take into account the shape and / or the dimensions of the wiper blade, which further increases the possibilities of application.

Anyway, the invention as defined thus has the advantage of being particularly easy to manufacture. The wiper blade has indeed a profile offering great stability in bed position. It can therefore be effectively supported during a flat extrusion; the heel and the lip resting simultaneously on the support surface. This will have the effect of preventing the deformations by gravity, and thus to ensure optimal geometry to the blade whose number of rejects will then be significantly reduced. All this explains why in the end, a wiper blade according to the invention is significantly less expensive and offers improved wiper quality compared to its counterparts of the state of the art.

Another advantage of the invention is to allow a simplification of the profile geometry. Due to the high dimensional stability of the blade, it is indeed possible to increase the height of the hinge to have all the flexibility necessary for the proper functioning of said blade, and thus to dispense with the complex profiles of the blade. prior art. This improves the cold performance of the blade, increase the resistance to the permanent deformation of the hinge, and provide some stability to the profile when it is weakly solicited in terms of support force.

This simplification of geometry also allows a reduction in the height of the profile, especially when the wedging of the blade takes place on the support structure. This will logically generate a significant improvement in the aerodynamic performance of the broom. It will thus be possible to opt for a lower power drive motor, which means at the same time less expensive, less energetic and less bulky. But this will also reduce the support force required to plating the blade, with the key a significant reduction in wear of the blade. The present invention also relates to the features that will emerge during the following description, which should be considered in isolation or in all their possible technical combinations. This description, given by way of non-limiting example, is intended to better understand what the invention is and how it can be achieved. It is also given with reference to the appended drawings in which:

Figures 1 to 4 are cross sections. Figure 1 shows a wiper blade which is equipped with a wiper blade according to a first embodiment of the invention. Figure 2 partially illustrates an alternative embodiment of the windscreen wiper blade of Figure 1. [0019] Figure 3 shows a wiper blade with a wiper blade according to a second embodiment of the invention. Figure 4 shows a wiper blade provided with a wiper blade according to a third embodiment of the invention. For the sake of clarity, the same elements have been designated by identical references. Likewise, only the essential elements for understanding the invention have been represented, and this without regard to the scale and in a schematic manner. Figure 1 illustrates a wiper blade 1 which in this particular embodiment, chosen solely by way of example, is flat blade type.

There is therefore essentially a wiper blade 10 of flexible material, which is supported by a flexible structure 20. But we also note the presence of a spoiler 30 which is responsible for optimizing the aerodynamic performance of the blade 1. [0023] In the detail, the wiper blade 10 is constituted by an elastomeric profile, which is mainly composed of a heel 11 and a lip

12 articulated to each other via a portion of smaller section, The support structure 20 is in the form of a plastic profile 21 which incorporates an inner housing 22 in which is inserted a metal vertebra 23, and a holding rail 24 in which takes place the heel 11 of the wiper blade 10. Finally, the spoiler 30 is also constituted by a profile 31, but it is made of elastomer and is secured to the upper part of the profile 21.

According to the object of the present invention, the heel 11 and the lip 12 have substantially identical widths.

In this first embodiment, the assembly is arranged so that the lip 12 always wedges against the support structure 20 when the blade 1 is moved laterally in contact with a surface to be wiped. Therefore, particularly advantageously, the blade 1 is further provided with abutment means 40 which are integral with the support structure 20, and which are able to damp the contact between the lip 12 and said support structure 20.

Specifically, the abutment means 40 have two damping elements 41, 42 which are positioned under the support structure 20 respectively on either side of the wiper blade 10, and which are able to cooperate by contact. blocking with the proximal portion of the lip 12, that is to say the portion directly contiguous to the hinge 13.

As can be seen clearly in Figure 1, the implementation of the damping elements 41, 42 is located at the portions of the support structure 20, which extend in the direct vicinity of the wiper blade 10. More specifically, they are arranged all at once, on either side of the hinge 13, and facing the shoulders which are formed at the proximal portion of the lip 12 to ensure wedging.

Accordingly, if the first function of the damping elements 41, 42 is to form flexible stops for the wedging of the lip 12, the fact remains that their implementation also leads them to play a role of screen vis-à-vis the most fragile portion of the wiper blade 10, namely the hinge 13. Thus interposed, the damping elements 41, 42 are indeed able to avoid any accumulation of material likely to disturb the operation of the blade 10, and / or any direct exposure to a photochemical attack capable of rapidly deteriorating the hinge 13.

In this logic, and according to an advantageous characteristic of the invention, each damping element 41, 42 extends over substantially the entire length of the support structure 20.

It should be noted that such a feature optimizes both the soft stop function, that protection screen.

According to a feature of the invention, each damping element 41, 42 may have a cellular and / or fibrous structure able to deform elastically.

By way of example, mention may be made of a foam based on polyurethane, polyethylene, butadiene-styrene rubber (SBR), etc. But it can also be a flocking based in particular polyamide fibers (PA 6.6), polyester fibers, vegetable fibers (cotton).

In such a case, the shock absorbing capacity results from a structural effect, that is to say the elastic deformation capacity offered by the structure of each damping element 31, 31.

According to another feature of the invention, each damping element 41, 42 may be made of an elastically deformable material.

Here, for example, a material based on polynorbornene (PNB), isobutene-isoprene rubber (MR), etc. is used.

In such a case, the shock absorption capacity derives directly from the intrinsic damping properties of the material constituting each damping element 41, 42. It should be noted that this second damping solution is less interesting than the previous one which favored structural deformation.

Anyway, in the embodiment shown in Figure 1, the damping elements 41, 42 are very concretely constituted by flocking based on polyamide fibers PA 6.6, which are fixed under the plastic section 21 using a one-component PU type glue. For this, the section 21 has been previously treated with a plasma to improve the adhesion of the adhesive. Once the latter has been applied, the fibers have been deposited in a magnetic field on the glued portion only, by implementing a conventional flocking process. The profiled assembly 21 / glue / fibers was then mounted in temperature in order to crosslink the glue, and thus to ensure maximum attachment of the fibers on the section 21.

Figure 2 shows a flat blade 2 which is only a simple variant of the first described. This second example of embodiment is essentially distinguished by the fact that it has no abutment means 40, but also that the shoulders 14, 15 of the lip 12, which are responsible for bearing against the support structure 20, are bevelled so that the respective contact surfaces are substantially parallel when the setting is effective. This feature maximizes the contact area between the lip 12 and the support structure 20, which provides better energy dissipation, and consequently a greater damping capacity of the impact.

The third embodiment, object of Figure 3, shows meanwhile a flat blade 3 which differs from the other two by the specific profile of its wiper blade 10. The latter is indeed shaped so that the wedging of the lip 12 is effected on the heel 11, by bearing a shoulder 14, 15 on a flexible stop 16, 17 formed at the level of said heel 11.

Figure 4 corresponding to a flat broom 4 of old generation. It is observed in fact that in this fourth embodiment, the support structure 20 is composed of two tongues 25, 26 elastically deformable, which are integrated longitudinally at respectively each face of the wiper blade 10. What it in either, the wedging of the blade 10 operates here on itself, but with this time the shoulders 14, 15 coming directly into contact with the heel 11, unlike the third embodiment which has specific soft stops 16, 17 .

Of course, the invention more generally relates to any wiper blade 1, 2, 3, 4 comprising a support structure 20 elastically deformable, and a wiper blade 10 of flexible material, such as previously described. Finally, the invention also relates to a method of manufacturing a wiper blade 10 as previously described. This is remarkable in that it comprises a step of extruding the blade 10 flat, while simultaneously resting the heel 11 and the lip 12 on a support surface.

Claims

claims

A wiping blade (10) for a wiper blade (1, 2, 3, 4), comprising a bead (11) and a lip (12) connected together by a portion of lesser hinge section (13). ), characterized in that the lip (12) has a width substantially identical to that of the heel (11).

2. Wiper blade (1, 2, 3, 4) comprising a wiper blade (10) of flexible material, which is supported by an elastically deformable structure (20), characterized in that the blade of wiping (10) is according to the preceding claim.

3. Wiper blade (1) according to claim 2, characterized in that the lip (12) is intended to be wedged against the support structure (20) when the blade (1) is moved laterally in contact with a surface to be wiped, said blade (1) further comprises stop means (40) which are integral with the support structure (20) and which are able to damp the contact between the lip (12) and said support structure (20). ).

4. Wiper blade (1) according to claim 3, characterized in that the stop means (40) comprise two damping elements (41, 42) which are positioned under the support structure (20) respectively from other of the wiper blade (10), and which are adapted to cooperate by blocking contact with the proximal portion of the lip (12).

5. Wiper blade (1) according to claim 4, characterized in that each damping element (41, 42) extends over substantially the entire length of the support structure (20).

6. wiper blade (1) according to one of claims 4 or 5, characterized in that each damping element (41, 42) is made of an elastically deformable material.

7. wiper blade (1) according to any one of claims 4 to 6, characterized in that each damping element (41, 42) has a cellular and / or fibrous structure able to deform elastically.

8. A method of manufacturing a wiper blade (10) according to claim 1, characterized in that it comprises a step of extruding the blade (10) flat by simultaneously resting the heel (11) and the lip (12) on a support surface.