The present invention relates to a connecting device for interconnecting a windscreen wiper device of the flat blade type and an oscillating arm pivotally connectable to said connecting device about a pivot axis near one end thereof, wherein said windscreen wiper device comprises an elastic, elongated carrier element, as well as an elongated wiper blade of a flexible material, which can be placed in

abutment with a windscreen to be wiped, which wiper blade includes at least one groove, in which groove a longitudinal strip of the carrier element is disposed.

Further, the present invention also relates to a windscreen wiper device of the flat blade type comprising an elastic, elongated carrier element, as well as an elongated wiper blade of a flexible material, which can be placed in

abutment with a windscreen to be wiped, which wiper blade includes at least one groove, in which groove a longitudinal strip of the carrier element is disposed, which windscreen wiper device comprises said connecting device for an

oscillating arm, wherein said oscillating arm can be

pivotally connected to said connecting device about a pivot axis near one end thereof.

Finally, the present invention also refers to a method for manufacturing said windscreen wiper device.

In the framework of the present invention the following is noted. Said connecting device, also called "connector", is preferably made in one piece, wherein said one-piece

connector is particularly made of plastic. The wiper blade being preferably made of an elastomer material, such as rubber, is preferably made through extrusion. Particularly, for use on a front windscreen to be wiped, said wiper blade comprises a spoiler (also called an "air deflector") at a side thereof facing away from the windscreen to be wiped, wherein said wiper blade and said spoiler are preferably made in one piece. Said longitudinal strip is also called a "flexor". Preferably, ends of said longitudinal strip (s) are connected by a respective connecting piece, also called an "end cap" .

In use, said oscillating arm is connected to a mounting head mounted on a drive shaft, wherein said oscillating arm at one end thereof is pivotally connected to the mounting head by means of a pivot pin and at another end thereof is connected to said wiper blade placed in abutment with said windscreen to be wiped. In use, the shaft rotates

alternately in a clockwise and in a counter-clockwise sense carrying the mounting head into rotation also, which in turn draws the oscillating arm into rotation and by means of said connecting device moves the wiper blade. Said oscillating arm can thus oscillate to-and-from between a first and second reversal positions.

It is noted that the present invention is not restricted to automobiles, but also refers to rail coaches and other (fast) vehicles.

Further, it is noted that the present invention is not restricted to the use of only one longitudinal strip forming the elastic carrier element that is particularly located in a central longitudinal groove of the wiper blade. Instead, said carrier element may also comprise two longitudinal strips, wherein said strips are disposed in opposite longitudinal grooves of the wiper blade. Said groove (s) may be closed at one outer end.

Such a connecting device and such a windscreen wiper device are generally known. This prior art windscreen wiper device is designed as a "flat blade" or "yokeless blade", wherein no use is made of several yokes pivotally connected to each other, but wherein the wiper blade is biased by the carrier element, as a result of which it exhibits a specific curvature .

In practice it has become apparent that there is a need for a connecting device being better connected to the

longitudinal strip (s) in use and being able to withstand high forces exerted on the connection between the connecting device and the longitudinal strip (s) .

The object of the invention is to provide an improved connecting device for interconnecting a windscreen wiper device of the flat blade type and an oscillating arm, wherein the connecting device is better connected to the longitudinal strip (s) and has a broader use and is able to withstand high forces, using a minimum of parts. Thereto, a connecting device of the type referred to in the introduction is characterized according to the invention in that said connecting device is arranged to be connected to said longitudinal strip through a welding operation, preferably an ultrasonic welding operation, wherein said connecting device comprises a support for supporting said longitudinal strip, and wherein said support is provided (before welding) with a profile along at least a portion of its upper surface. Preferably, said profile is provided along the entire upper surface of the support for the longitudinal strip. The gist of the present invention is to reduce by means of said profile a contact surface between the longitudinal strip on the one hand and the connecting device on the other hand at the location of there

interconnection, i.e. at the location where the longitudinal strip and the support of the connecting device are welded together. Particularly during ultrasonic welding, heat caused by vibrations is directed in an area of said

interconnection, resulting in local melting of the materials of said longitudinal strip and said support of said

connecting device. After cooling a link is obtained between said materials. In other words, reduction of said contact surface between the longitudinal strip on the one hand and the connecting device on the other hand at the location of there interconnection, ensures that the heat generated by said welding is efficiently concentrated along said profile, so that said welding can take place in a uniform and fast manner. Hence, a universal connecting device is obtained allowing connection to the longitudinal strip using a welding operation.

Preferably, the connecting device is made of a polymer material, whereas said longitudinal strip is either made in one piece of a polymer material as well, or provided with a polymer skin, i.e. coating. In assembled position of the connecting device, the wiper blade and the longitudinal strip, making use of said welding operation with the help of a ultrasonic head accommodated in said hole, the polymer material of the connecting device and the longitudinal strip will locally melt, namely at a location of their

interaction, ensuring a firm interconnection between them. Once the interconnection is established, the ultrasonic head will be retracted, so that a unit comprising of the

connecting device, the wiper blade and the longitudinal strip is ready for use, i.e. is ready to be connected to an oscillating arm.

Said hole is preferably a blind hole, wherein the

longitudinal strip rests on a bottom of said blind hole. Said bottom is then the location of interaction between the connecting device and the longitudinal strip in case a welding operation is used, as explained above. Particularly, said hole is open from a top of said connecting device to allow said electrode access from above through said hole to contact said longitudinal strip, as explained above. It is noted that that the term "welding" in the framework of the present invention also encompasses the term "soldering", wherein in the latter case a soldering material, preferably a polymer material as well, is locally applied between the connecting device and the longitudinal strip (or skin of the longitudinal strip) .

In a preferred embodiment of a connecting device in

accordance with the invention said profile comprises several ribs protruding upwardly from said upper surface.

Preferably, said ribs extend in longitudinal direction of the wiper blade in use. Hence, the welding area is

increased .

In another preferred embodiment of a connecting device according the invention said engaging members are arranged to engage around longitudinal strips of the carrier element disposed in opposing grooves of the wiper blade. In another preferred embodiment of a connecting device in accordance said connecting device comprises two pairs of holes, wherein each pair comprises opposing holes, and wherein each pair is located near an end wall of said connecting device.

The present invention also relates to a windscreen wiper device of the flat blade type comprising an elastic, elongated carrier element, as well as an elongated wiper blade of a flexible material, which can be placed in

abutment with a windscreen to be wiped, which wiper blade includes at least one groove, in which groove a longitudinal strip of the carrier element is disposed, wherein said windscreen wiper device further comprises a connecting device according to the invention for pivotally connecting an oscillating arm to said connecting device about a pivot axis near one end thereof.

The present invention also refers to a method for

manufacturing a windscreen wiper device comprising an elastic, elongated carrier element, as well as an elongated wiper blade of a flexible material, which can be placed in abutment with a windscreen to be wiped, which wiper blade includes at least one groove, in which groove a longitudinal strip of the carrier element is disposed, which windscreen wiper device comprises a connecting device for an

oscillating arm, wherein said oscillating arm can be

pivotally connected to said connecting device about a pivot axis near one end, characterized in that said connecting device is welded to said longitudinal strip, wherein said connecting device comprises a support for supporting said longitudinal strip, and wherein said support is provided before welding with a profile along at least a portion of its upper surface. Preferably, said connecting device is provided with at least one hole arranged to allow an

ultrasonic head access through said hole to contact said longitudinal strip for welding said longitudinal strip and said connecting device together.

The invention will now be explained in more detail with reference to figures illustrated in a drawing, wherein - Figure 1 is a schematic and perspective view of a

windscreen wiper device of the flat blade type and an oscillating arm according to the invention;

- Figure 2 are schematic, perspective views (above) of a connecting device according to the invention, used in the windscreen wiper device of figure 1, as well as cross-sectional views (below) thereof showing how the connecting device is connected through ultrasonic welding .

Figure 1 shows a windscreen wiper device 1 of the "flat blade" type according to the invention. Said windscreen wiper device 1 is built up of an elastomeric wiper blade 2, in the longitudinal sides of which opposing longitudinal grooves 3 are formed, and of longitudinal strips 4 made of spring band steel, which are fitted in said longitudinal grooves 3. Said strips 4 form a flexible carrier element for the rubber wiper blade 2, as it were, which is thus biased in a curved position (the curvature in operative position being that of a windscreen to be wiped) . Neighbouring ends of strips 4 are interconnected on either side of the

windscreen wiper device 1 by means of connecting pieces or "end caps" functioning as clamping members. In this embodiment, the connecting pieces may be separate constructional elements, which may be form-locked ("positive locking" or "having positive fit"), as well as force-locked to the ends of strips 4. In another preferred variant, said connecting pieces are in one piece with the strips 4 made of spring band steel. In the latter case said connecting pieces form transverse bridges for the strips 4, as it were.

Possibly, a spoiler 5 is furthermore provided. With reference to figure 2, the windscreen wiper device 1 is furthermore built up of a connecting device 6 of plastic material for an oscillating wiper arm 7. Said connecting device 6 comprises two cylindrical protrusions 8 extending outwards on either side thereof, i.e. on each vertical side wall thereof. These protrusions 8 pivotally engage in identically shaped cylindrical holes of a joint part or adapter (not shown) . In case of a rear windscreen to be wiped, the connecting device 6 is directly connected to the rear wiper arm 7, as shown in figure 1, i.e. without any joint part or adapter. Said protrusions 8 act as bearing surfaces at the location of a pivot axis in order to pivot the joint part (and the oscillating wiper arm 7 attached thereto) about said pivot axis near a free end of said oscillating wiper arm 7. The protrusions 8 are preferably in one piece with said connecting device 6. In the alternative, the protrusions 8 are part of a single pivot pin

perpendicular to the connecting device 6.

Referring to figure 2, with the help of two pairs of

ultrasonic heads 9 accommodated in corresponding blind holes 10 of the connecting device 6, the polymer material of the connecting device 6 and the longitudinal strips 4 will locally melt together, namely at a location 11 of their interaction, ensuring a firm interconnection between them. Once the interconnection is established, the ultrasonic tool 9 will be retracted, so that a unit comprising of the connecting device 6, the wiper blade 2 and the longitudinal strips 4 is ready for use.

As shown in figure 2, said connecting device 6 comprises engaging members 12 made integral therewith arranged to engage around said longitudinal strips 4, wherein each engaging member 12 forms a slit 13 arranged for receiving one of said longitudinal strips 4 therein. A bottom wall 14 of said slit 13 is provided with a profile comprising several longitudinal ribs 15 protruding upwardly from said bottom wall 14. Thus, the ribs 15 ensure that the contact surface between each longitudinal strip 4 on the one hand and the bottom wall 14 of each slit 13 on the other hand at the location of there interconnection is reduced, so that the heat generated by the ultrasonic tool 9 is uniformly and efficiently applied on a lager welding area.

The invention is not restricted to the variants shown in the drawing, but it also extends to other embodiments that fall within the scope of the appended claims.