BE1021205B1 - WIPER BLADE - Google Patents

Abstract

Wiper blade (10) comprising a wiper blade (14) carrying stiffeners (62, 64) attached to stiffener supports (22, 24) of a connecting member (100). The stiffeners (62, 64) have a sheath (82, 84) of a first thermoplastic material at least in the area of the stiffener supports (22, 24). At least one stiffener support (22, 24) includes the first thermoplastic material at least in the region of the associated stiffener (62, 64).

Description

"WIPER BLADE"

Field of the invention

The present invention relates to a wiper blade comprising a wiper blade carrying stiffeners attached to stiffener supports of a connecting element, the stiffeners having a sheath of a first thermoplastic material at least in the zone stiffener supports. The invention also relates to a wiping blade wiper blade connecting element provided with stiffeners fixed in associated stiffener supports of the connecting element, the stiffeners having at least one stiffeners, a plastic sheath made of a first thermoplastic material.

Finally, the invention relates to a method of welding a stiffener of a wiper blade of a wiper blade with an associated stiffener support of a connecting element, the stiffener and the stiffener support comprising at least in segments, thermoplastic material.

State of the art

According to the state of the art, so-so-ice-cream brooms are known whose wiper blades or windscreen wiper blades have a back or a dorsal rod receiving stiffeners generally made in the form of blades. elastic. These stiffeners or rails are held in stiffening supports of a connecting element comprising a fastening element, for example a retaining spring to be attached to an associated arm of a windshield wiper. In the case of conventional wipers, the stiffener supports are generally made of polybutylene terephthalate (PBT) reinforced with glass fibers and the stiffeners have a sheath or envelope of polyethylene terephthalate (PET).

When assembling such windscreen wiper blades, the stiffeners are firstly installed in the stiffener supports so as to leave between them an interval allowing the wiper blade to slide therethrough. The stiffeners are then ultrasonically welded or friction welded to the stiffener supports to avoid any troublesome reduction in the gap between the stiffeners.

The wiper blade will then be slid from an axial end of the connecting member into the gap between the stiffeners. The disadvantage of the state of the art is that by welding the stiffeners, one can not achieve a homogeneous weld with the stiffeners because PET and PBT have different properties such as for example the structure, the melting point and the viscosity. If at welding for example, the PBT of the stiffener support does not reach the same viscosity as the PET stiffeners, the mixture of these thermoplastics will be limited.

Purpose of the invention

The object of the present invention is to develop a windscreen wiper blade having a stable and guaranteed fixation of the stiffeners in the stiffener supports of an associated connecting element, so as to have a sufficient gap between the stiffeners for sliding a blade of 'wiping.

DESCRIPTION AND ADVANTAGES OF THE INVENTION To this end, the invention relates to a windscreen wiper blade of the type defined above, characterized in that at least one straightener support comprises the first thermoplastic material at least in the associated stiffener area. The invention thus makes it possible to produce a windscreen wiper whose stiffeners and stiffener supports have the same thermoplastic material so that, when soldering, there will be a substantially homogeneous bond between the stiffeners and the stiffener supports.

Preferably, at least one stiffener support is made in segments with a second plastic material. This makes it possible to develop an economical connection element for the wiper blade.

At least one stiffener support preferably comprises a longitudinal channel in the form of a groove for receiving the associated stiffener. The first thermoplastic material is generally provided by segment in the region of the longitudinal channel. This makes it possible to easily introduce stiffeners into the dissay supports and connect them to them.

Preferably, a stiffener support carries a fixing member at least in segments surrounding the groove-shaped longitudinal channel and comprises the first thermoplastic material. At least this stiffener support is preferably made in one piece with the plastic injection fixing element in two-component injection technique. The invention thus makes it possible to develop an economic connection element that is simple to manufacture for a windscreen wiper blade according to the invention.

According to one embodiment, at least one stiffener support is welded to the associated stiffener and the fusion of the first thermoplastic material of the stiffener support with the first thermoplastic material of the associated stiffener, will thus be achieved. At least this stiffener support is preferably welded by laser beam welding to the associated stiffener.

This allows a simple way to obtain a very homogeneous welded connection between the stiffeners and stiffener supports of the wiper blade according to the invention.

The first thermoplastic material preferably comprises polyethylene terephthalate and / or a polyester-based plastic powder.

The wiper blade can thus be provided with an economical connection element.

The problem mentioned above is also solved by a wiper blade connection element to the wiper blade on the stiffeners attached to the associated supports of the stiffeners of the connecting element. At least in the area of the stiffener supports, the stiffeners have a plastic sheath made of a first thermoplastic material. At least one stiffener support has a groove-shaped longitudinal channel for receiving the associated stiffener and this channel is at least in segments surrounded by a fastener provided on the stiffener support to secure the associated stiffener. The fastener comprises the first thermoplastic material and the stiffener support, a second plastic material.

The problem mentioned above is also solved by a method of welding a stiffener provided on a wiper blade of a wiper blade with the associated stiffener support and forming part of a connecting element. The stiffener and the stiffener support have at least in segments of the thermoplastic material. For melting in a predefined area of the stiffener or stiffener support, energy is supplied to the thermoplastic material by laser radiation.

drawings

The present invention will be described in more detail below with the aid of embodiment examples shown schematically in the accompanying drawings, in which: FIG. 1 is an exploded view of a wiper blade provided with a connecting element to be articulated to a wiper arm according to the invention, Figure 2 is a sectional view of the wiper blade of Figure 1 substantially at the connecting member, the figure 3 is a sectional view of a stiffener support corresponding to a first embodiment with a stiffener welded to the support, and FIG. 4 is a sectional view of a stiffener support according to a second embodiment with a stiffener soldered to it. Description of the embodiments

Figure 1 shows several parts which, according to one embodiment, constitute a windscreen wiper blade 10, especially for cleaning a motor vehicle window. According to one embodiment, the wiper blade 10 corresponds to a beam structure or flat structure.

The wiper blade 10 comprises for example a deflector 88, 89 in two parts, two end caps 46, 48, two stiffeners (or support rails) 62, 64 and a wiper blade 14 having at least a wiper lip 20. To attach the wiper blade 10 to the associated wiper arm, preferably according to the principle of fixing by lateral locking or locking from above, there is provided a connecting element 100. This connection element 100 comprises for example a base adapter 120 and a retaining spring 110. According to one embodiment, base adapter 120 is hingelessly and permanently connected to stiffeners 62, 64 (support rails), as will be described hereinafter with reference to FIGS. 3 and 4. The retaining spring 110 attaches to the associated wiper arm and is hingedly connected to the base adapter 120.

The wiper blade 14 and / or the wiper lip 20 are preferably ethylene propylene rubber (EPDM) and / or polypropylene carbonate (PPC). The deflector 88, 89 is preferably made of rubber (EPDM) and / or polypropylene (PP). The end caps 46, 48 and the retaining spring 110 preferably comprise polyoxymethylene (POM). The base adapter 120 is preferably (PBT) reinforced with glass fibers; the glass fiber content preferably does not exceed 45%. The stiffeners or support rails 62, 64 are preferably made in the form of a flat blade with an outer metal layer, preferably activated (this layer bears the reference 72 in FIG. 4 and the reference 74 in FIG. 3). for example a layer of ZnAl with preferably a sheath of a thermoplastic material 82, 84 for example a PET layer and / or a layer of polyester-based powder.

Figure 2 is a sectional view of the wiper blade 10 of Figure 1 at the connecting member 100 after mounting. As shown in Figure 2, the wiper blade 30 has a back 50 held by the base adapter 120 and this back is connected to the wiper lip 20 by a tilting spacer 34 connected in the axial direction of the blade 14. The back 50 comprises at least one support spar 52 connected by a spacer 55 directed in the axial direction of the blade 14, to at least one supporting spar 54 to form between the support spar 52 and the support spar 54, cavities 51, 53 in the form of grooves; to simplify the description, these cavities will be called hereinafter "longitudinal grooves". The longitudinal grooves 51, 53 receive the stiffeners 62, 64. The base adapter 120 connected to the fixing spring 110 for example by a hinge pin, comprises fasteners stiffeners 22, 24 which face each other. These fasteners each form a longitudinal channel 27, 29 in the form of grooves of substantially rectangular section to receive the stiffeners 62 or 64. At least in the region of the longitudinal channel 29, according to one embodiment, there is provided at least in segments a fixing element 99, for example U-shaped to fix the stiffener 64, as will be described hereinafter with reference to FIG.

It should be noted that the rail fasteners 22, 24 of Figure 2 are shown differently only by way of example and this difference should not be understood as a limitation of the invention. Moreover, the two rail fasteners 22, 24 may have substantially the same structure.

The stiffeners 62, 64 are preferably made in the form of elastic rails; in section the stiffeners preferably have a rectangular profile with longitudinal surfaces substantially flat or straight as shown in Figures 3 and 4. These elastic rails are manufactured as described above from a flat wire or for example one or more rolling operations from a profiled wire, round, according to one embodiment. Such rolling operations make it possible to produce any profile so that the rectangular profile described above has only an exemplary character and not a limit of the invention. According to one embodiment, the support rails 62, 64 once the desired profile has been obtained, receive an outer metal layer which will be enveloped by a layer of thermoplastic material as will be described hereinafter with reference to FIGS. .

Figure 3 is a detail view of the part with the reference 300 in Figure 2 of the stiffener 64 fixed in the longitudinal channel 29 in the form of a groove of the stiffener support 24; as has been described with reference to FIGS. 1 and 2, the stiffener is made from a flat wire provided with an outer layer, preferably an activated metal layer 74. This is for example a layer of ZnAl and at least in the area of the stiffener support 24, the stiffener comprises a plastic sheath 84. The plastic sheath 84, according to one embodiment, is a selected thermoplastic material, preferably PET and / or a plastic powder based on polyester. The plastic casing 84 is preferably designed to fulfill predefined quality criteria, in particular for its attachment to the metal layer 74 and any variations in the thickness of material.

The stiffener support 24 comprises this thermoplastic material selected at least also in the area of the stiffener 64; moreover, it will be made at least in segments of another plastic material meeting predefined conditions of rigidity and / or weather resistance. For example, the stiffener support 24 may be made of glass fiber reinforced PBT as described in connection with FIG. 1; the glass fiber content preferably does not exceed more than 45%; for example in the area of the longitudinal channel 29, there will be at least PET segments and / or polyester-based plastic powder.

According to one embodiment, the stiffener support 24 is provided with a fixing element 99. This element surrounds the groove-shaped longitudinal channel 29 at least in segments and is preferably made of the selected thermoplastic material, for example PET. . Figure 3 illustrates by way of example a U-shaped embodiment of the fastener 99; this element comprises a longitudinal groove 310 receiving the stiffener 64.

The stiffener support 24 is preferably made by injecting plastic material according to the two-component injection technique to form a body with the fastening element 99. It should however be noted that this embodiment in one piece by injection of material plastic, is only given by way of example without limiting the invention. For example, the fastening element 99 may be made as a separate piece that is fixed in the stiffener support 24, for example by clamping or hooking; the stiffener support 24 may be made of plastic or other suitable material, for example metal.

According to one embodiment, the stiffener support 24 or the fixing element 99 are welded to the stiffener 64 for example by ultrasonic welding, friction welding or laser welding. This results in a melting of the thermoplastic material of the fixing element 99 with the thermoplastic material of the envelope 84 of the stiffener 64 to arrive at a connection by the essentially homogeneous material between the stiffener 64 and the stiffener support 24 .

FIG. 4 shows the detail view bearing the reference 400 in FIG. 2 of the longitudinal channel 27 in the form of a groove of the stiffener 62 fixed in the stiffener support 22. Like the stiffener 64 of FIGS. 1 to 3, the stiffener 62 is also preferably in the form of a ribbon; it comprises an outer metal layer 74 preferably activated, for example a layer of ZnAl, and it is provided with a plastic envelope 82 at least in the region of the stiffener support 22; this plastic sheath corresponds, according to one embodiment, to a thermoplastic material preferably selected from PET and / or polyester-based plastic powder.

The stiffener support 22 comprises this selected thermoplastic material, for example PET, preferably also in the region of the stiffener 62; moreover, the support can be made as described for the support 24 in Figure 3. Alternatively, the stiffener support 22 can also be made entirely with another thermoplastic material. For example, the stiffener support 22 may be made entirely of glass fiber reinforced PBT as described in FIG. 1; the glass fiber content will preferably be at most equal to 45%.

According to one embodiment, the stiffener support 22 is welded to the stiffener 62 by laser welding. In the case where the stiffener support 22 and the stiffener 62 comprise for example PET, the PET provided in the stiffener support 22, in a predefined zone 90, is supplied with energy by a laser beam 420 emitted by the source of radiation 410. This energy is provided punctually in a given geometric pattern, for example a circle or poly-gone and / or a predefined length, for example 15 to 30 mm. This energy will be absorbed by the PET. This results in a temperature rise of the stiffener support 22 which, in turn, heats the PET of the plastic sheath 82 of the stiffener 62 producing a melting of the PET and the support 22 with the PET of the plastic sheath. 84 of the stiffener 64 to give a connection by the material, substantially homogeneous.

In the case where the stiffener support 22 is, for example, entirely made of glass fiber-reinforced PBT, PET of the plastics material 82 of the stiffener 62 is provided with the laser radiation 420 supplied by the radiation source 410, the energy punctually or according to a predefined geometric pattern, for example a circle or a polygon and / or a predefined length, for example from 15 to 30 mm. This energy will be absorbed by the PET. This produces a rise in temperature of this PET which in turn heats the PBT of the stiffener support 22 to melt PET with PBT.

It should be noted that the laser beam welding is sufficiently known to specialists so that it is not necessary to proceed to a detailed description of the welding operation according to the invention. It should be noted, however, that in order to obtain a substantially homogeneous plugging zone or weld connection, according to the welding operations described above, the stiffeners 62, 64 of FIGS. 3 and 4 must be held during welding preferably. without leaving an interval with the stiffener support 22 or 24 corresponding according to Figures 3 and 4.

NOMENCLATURE 10 wiper blade 14 wiper blade 20 wiper lip 22, 24 stiffener support 27, 29 longitudinal channel 34 tilt spacer 46.48 end cap 50 back 51.53 longitudinal groove 52 , 54 support beam 55 spacer 62, 64 stiffener 74 activated metal layer 82, 84 plastic sheath 88.89 deflector 90 zone 99 fastening element 100 connecting element 110 retaining spring 120 base adapter 310 longitudinal groove 410 source 420 laser beam radiation

Claims (9)

1) Wiper blade (10) comprising a windscreen wiper blade (14) carrying stiffeners (62, 64) fixed to stiffener supports (22, 24) of a connecting element ( 100), the stiffeners (62, 64) having a sheath (82, 84) of a first thermoplastic material at least in the region of the stiffener supports (22, 24), characterized in that at least one stiffener support ( 22, 24) comprises the first thermoplastic material at least in the region of the associated stiffener (62, 64), and at least one stiffener support (22, 24) is made at least in segments, in a second plastic material. Windscreen wiper blade according to Claim 1, characterized in that at least one stiffener support (22, 24) has a groove-like longitudinal channel (27, 29) for receiving the stiffener (62, 64) associated, the first thermoplastic material being provided at least in segments in the region of the longitudinal channel (27, 29). Windscreen wiper blade according to Claim 2, characterized in that at least one stiffener support (22, 24) has a fastening element (99) formed in the first thermoplastic material and at least in segments around it. the longitudinal channel (27, 29) in the form of a groove. Windscreen wiper blade according to Claim 3, characterized in that at least one stiffener support (22, 24) is formed in one piece with the fastening element (99) by plastic injection molding. in two-component injection technique. Windscreen wiper blade according to Claim 4, characterized in that at least one stiffener support (22, 24) is welded to the associated stiffener (62, 64), fusing the first thermoplastic material of the support. a stiffener (22, 24) being produced with the first thermoplastic material of the associated stiffener (62, 64). Windscreen wiper blade according to Claim 1, characterized in that at least one stiffener support (22, 24) is welded by laser beam welding to the associated stiffener (62, 64). The wiper blade according to claim 1, characterized in that the first thermoplastic material is polyethylene terephthalate and / or a polyester-based plastic powder. 8 °) Connecting element (100) of wiper blade (10) to a wiper blade (14) provided with stiffeners (62, 64) fixed in stiffener carriers (22, 24) associated with connecting member (100), the stiffeners (62, 64) having a plastic sheath (82, 84) made of a first thermoplastic material at least in the region of the stiffener supports (22, 24), characterized in that at least one stiffener support (22, 24) has a groove-shaped longitudinal channel (27, 29) surrounded at least in segments by a fastener (99) provided on the stiffener support (22, 24) for fixing the associated stiffener (62, 64), the fastener (99) comprising the first thermoplastic material and the stiffener support (22, 24) comprising a second plastic material. 9 °) A method of welding a stiffener (62, 64) of a wiper blade (14) of a wiper blade (10) with a stiffener support (22, 24) associated therewith a connecting element (100), the stiffener (62, 64) and the stiffener support (22, 24) having, at least in segments, thermoplastic material, characterized in that the thermoplastic material is provided with energy by laser radiation for melting in a predefined area (90) stiffeners (62, 64) or stiffener supports (22, 24).