WO2015158398A1

WO2015158398A1 - Windscreen wiper device

Info

Publication number: WO2015158398A1
Application number: PCT/EP2014/057973
Authority: WO
Inventors: Thomas Friscioni
Original assignee: Federal-Mogul S.A.
Priority date: 2014-04-17
Filing date: 2014-04-17
Publication date: 2015-10-22

Abstract

A windscreen wiper device (1) of the flat blade type comprising an elastic, elongated carrier element, as well as an elongated wiper blade (2) of a flexible material, which can be placed in abutment with a windscreen to be wiped, which wiper blade (2) includes at least one longitudinal groove (3), in which groove (3) at least one longitudinal strip (4) of the carrier element is disposed, which windscreen wiper device (1) comprises a connecting device (6) for an oscillating arm (7), wherein said oscillating arm (7) can be pivotally connected to said connecting device (6) about a pivot axis near one end thereof, with the special feature that said longitudinal strip (4) along its entire length comprises at least one longitudinally extending recess (12) having a U-shaped cross-section being identical over the entire length of said recess, wherein dimensions of said longitudinal strip (4) are prescribed by dimensions of said longitudinal groove (3).

Description

WINDSCREEN WIPER DEVICE

The present invention relates to a windscreen wiper device of the flat blade typecomprising 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 longitudinal groove, in which groove at least one 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 pxvotally connected to said connecting device about a pivot axis near one end thereof .

The present invention also refers to a method for manufacturing said windscreen wiper device . 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.

In the framework of the present invention said wiper blade preferably comprises a spoiler at a side thereof facing away from the windscreen to be wiped .

Such a windscreen wiper device is generally known . This prior art windscreen wiper device is designed as a so-called "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. The spoiler is also called an "air deflector".

The object of the invention is to provide an improved windscreen wiper device .

In order to accomplish that objective, a windscreen wiper device of the type referred to in the introduction is characterized according to the invention in that that said longitudinal strip along its entire length comprises at least one longitudinally extending recess having a U-shaped cross-section being identical over the entire length of said recess , wherein dimensions of said longitudinal strip are prescribed by dimensions of said

longitudinal groove . An important aspect of the present invention is that the longitudinal strip in the framework of the present invention has a width and a height such that it can readily be inserted with play, like its traditional counterpart strip, inside a longitudinal groove of a wiper blade already existing on the market. In other words, dimensions of said groove of an existing wiper blade defines or prescribes dimensions of the present longitudinal strip to be inserted in said groove . By applying said recess or groove open at its upper end in said longitudinal strip, its weight is significantly reduced, while its moment of inertia is close to or above the moment of inertia of its already existing counterpart, i.e. a conventional longitudinal strip or flexor. Accordingly, the force exerted by the oscillating arm onto the wiper blade, at the location of the connecting device or

connector, is distributed uniformly over the entire length of the wiper blade . In other words, the weight of the present

longitudinal strip (s) is decreased compared to conventional longitudinal strip (s) , while the pressure distributing

performances thereof are maintained. The rigidity of said

longitudinal strip in longitudinal direction thereof is increased with less material (compared to the prior art ) .

Said longitudinal strip is particularly made of band steel . In a preferred embodiment of a windscreen wiper device in

accordance with the invention said longitudinally extending recess is provided at a side of said longitudinal strip facing towards a windscreen to be wiped. In the alternative said longitudinally extending recess is provided at a side of said longitudinal strip facing away from a windscreen to be wiped. In both preferred variants said longitudinal strip has a U-shaped cross-section being constant in dimensions over its entire length .

In another preferred embodiment of a windscreen wiper device according to the invention two longitudinal ly extending recesses are provided, wherein a first longitudinally extending recess is provided at a side of said longitudinal strip facing towards a windscreen to be wiped, and wherein a second longitudinally extending recess is provided at a side of said longitudinal strip facing away from a windscreen to be wiped. Hence, said

longitudinal strip has a H-shaped cross-section being constant in dimensions over its entire length .

In another preferred embodiment of a windscreen wiper device in accordance with the invention said longitudinal strip has

0,5 > h > 2 mm

5 > b > 12 mm

0, 05 > d > 1,8 mm

wherein b is equal to the width and h is equal to the height of said longitudinal strip (4) , and wherein d is equal to the depth of said recess (12) . As indicated, the present invention is also related to a method for manufacturing a windscreen wiper device of the flat blade type according to the present invention, 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 longitudinal groove, in which groove at least one 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 thereof, characterized in that at least one longitudinally extending recess is provided in said longitudinal strip along its entire length, wherein said recess is provided with a U-shaped cross-section made identical over the entire length of said, recess, and wherein dimensions of said longitudinal strip are adapted to dimensions of said longitudinal groove .

Said longitudinally extending recess is made inside said

longitudinal strip by manufacturing said longitudinal strip through a laminating process. In the alternative said

longitudinally extending recess is made inside said longitudinal strip by a material removing operation .

The invention will now be explained more in detail with reference to figures illustrated in a drawing, wherein figure 1 is a perspective, schematic view of a preferred embodiment of a windscreen wiper device according to the invention, with (a part of) an oscillating arm;

figure 2 is a cross- sectional view of a longitudinal strip according to the prior art to be used in a windscreen wiper- device;

figure 3 corresponds to figure 2, but shows a longitudinal strip according to a first preferred embodiment of the invention, as used in a windscreen wiper device of figure 1; and

figure 4 corresponds to figure 2, but shows a longitudinal strip according to a second preferred embodiment of the invention, as used in a windscreen wiper device of figure 1.

Figure 1 shows a preferred variant of a windscreen wiper device 1 according to the invention . Said windscreen wiper device is built up of an elastomeric (rubber) wiper blade 2 comprising a central longitudinal groove 3, wherein a longitudinal strip 4 made of spring band steel is fitted in said longitudinal groove 3. Said strip 4 forms 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) . An end of said strip 4 and/or an end of said wiper blade 2 is connected on either side of the windscreen wiper device 1 to respective connecting pieces or "end caps" 5. In this embodiment, the connecting pieces 5 are separate constructional elements, which may be form-locked as well as force-locked to both ends of said strip 4 and/or ends of said wiper blade 2. In another preferred variant, said connecting pieces 5 are in one piece with the strip 4 made of spring band steel. The windscreen wiper device 1 is furthermore built up of a connecting device 6 of metal for connecting an oscillating wiper arm 7 thereto, with the

interposition of a joint part 8. The oscillating wiper arm 7 is pivotally connected to the connecting device 6 about a pivot axis near one end. The preferred embodiment of figure 1 according to the invention comprises a spoiler or "air deflector" 9 which is made in one piece with the rubber wiper blade 2 and which extends along the entire length thereof.

As can be seen in figure 1 , the joint part 8 comprises a resilient tongue 10 extending outwardly, while the oscillating arm 7 has an ϋ-shaped cross-section at the location of its connection to said joint part 8, so that the tongue 10 engages in an identically shaped hole 11 provided in a base of said U-shaped cross-section . The connecting device 6 with the wiper blade 2 is mounted onto the oscillating arm 7 as follows . The joint part 8 being already clipped onto the connecting device 6 is pivoted relative to the connecting device 6, so that said joint part 8 can be easily slid on a free end of the oscillating arm 7. During this sliding movement the resilient tongue 10 is initially pushed in against a spring force and then allowed to spring back into said hole 11, thus snapping, that is clipping the resilient tongue 10 into the hole 11. This is a so-called bayonet-connection, The oscillating arm 7 together with the joint part 8 may then be pivoted back in a position parallel to the wiper blade 2 in order to be ready for use. By subsequently pushing in again said resilient tongue 10 against the spring force (as if it were a push button) , the connecting device 6 and the j oint part 8 together with the wiper blade 2 may be released from the oscillating arm 7. Dismounting the connecting device 6 with the wiper blade 2 from the

oscillating arm 7 is thus realized by sliding the connecting device 6 and the joint part 8 together with the wiper blade 2 in a direction away from the oscillating arm 7.

Although not shown in figure 1, but fully understood by a skilled person, said oscillating arm 7 is connected to a mounting head fixed for rotation to a shaft driven by a small motor. In use, the shaft rotates alternately in a clockwise and in a counterclockwise sense carrying the mounting head into rotation also, which in turn draws said oscillating arm 7 into rotation and by means of said connecting device 6 moves said wiper blade 2.

Figure 2 is a cross-sectional view of a standard, well known longitudinal strip 2 according to the prior art to be used in a windscreen wiper device . This known strip 4 has a width b of approximately 9 mm and a height h of approximately 1 mm, so that the cross-sectional surface thereof is approximately 8,97 mm².

Said longitudinal strip 4 has a moment of inertia I_x = (b*h³) /12 (along its middle longitudinal plane) of approximately 0.74*10*e^"12 kg*m², as well as I_y = (b³*h) /12 (along its middle transverse plane) of approximately 0.60*10*e^"10 kg*m².

Figure 3 corresponds to figure 2, but now according to the invention a longitudinally extending recess 12 is provided at a side of said longitudinal strip 4 facing away from a windscreen to be wiped. Said recess 12 has a depth d of approximately 0,6 mm, whereas the overall height h of said strip 4 is approximately 1, 2 mm. The width b' of said recess 12 is approximately 5 mm and the overall width b of said strip 4 is approximately 7, 4 mm². The present longitudinal strip 4 has a moment of inertia

(along its middle longitudinal plane) of approximately 0.76*10*e^-12 kg*m², as well as

(along its middle transverse plane) of approximately

Figure 4 corresponds to figure 3, but now according to the invention a longitudinally extending recess 12', 12'' is provided at both sides of said longitudinal strip 4, that is at a side facing away from a windscreen to be wiped, as well as at a side facing towards a windscreen to be wiped. The recesses 12' , 12 ' ' in figure 4 have the same dimensions as the recess 12 in figure 3, while also the overall width b and height h of the strip 4 in figure 4 equals those of the strip 4 depicted in figure 3, The moments of inertia are therefore also the same.

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

Claims

1. A windscreen wiper device (1) of the flat blade type

comprising an elastic, elongated carrier element, as well as an elongated wiper blade ( 2 ) of a flexible material, which can be placed in abutment with a windscreen to be wiped, which wiper blade (2) includes at least one longitudinal groove (3) , in which groove (3) at least one longitudinal strip (4) of the carrier element is disposed, which

windscreen wiper device (1) comprises a connecting device (6) for an oscillating arm (7) , wherein said oscillating arm (7) can be pivotally connected to said connecting device (6) about a pivot axis near one end thereof, characterized in that said longitudinal strip (4) along its entire length comprises at least one longitudinally extending recess (12) having a U-shaped cross-section being identical over the entire length of said recess, wherein dimensions of said longitudinal strip (4) are prescribed by dimensions of said longitudinal groove (3) .

2. A windscreen wiper device (1) according to claim 1, wherein said longitudinally extending recess (12) is provided at a side of said longitudinal strip (4 } facing towards a

windscreen to be wiped.

3. A windscreen wiper device (1) according to claim 1 , wherein said longitudinally extending recess (12) is provided at a side of said longitudinal strip (4 ) facing away from a windscreen to be wiped .

4. A windscreen wiper device (1) according to claim 1, 2 or 3, wherein two longitudinally extending recesses (12) are provided, wherein a first longitudinally extending recess (12' ) is provided at a side of said longitudinal strip (4) facing towards a windscreen to be wiped, and wherein a second longitudinally extending recess (12' ' ) is provided at a side of said longitudinal strip (4) facing away from a windscreen to be wiped. 5. Ά windscreen wiper device (1) according to any of the

preceding claims 1 through 4, wherein said longitudinal strip (4) has

0, 5 > h > 2 mm

5 > b > 12 mm

0, 05 > d > 1,8 mm

wherein b is equal to the width and h is equal to the height of said longitudinal strip (4) , and wherein d is equal to the depth of said recess (12) .

A method for manufacturing a windscreen wiper device (1)

6.

according to any of the preceding claims 1 through 5

comprising an elastic, elongated carrier element, as well as an elongated wiper blade (2) of a flexible material, which can be placed in abutment with a windscreen to be wiped, which wiper blade (2) includes at least one longitudinal groove (3) , in which groove (3) at least one longitudinal strip (4) of the carrier element is disposed, which

windscreen wiper device (1) comprises a connecting device (6) for an oscillating arm (7) , wherein said oscillating arm

(7) can be pivotaily connected to said connecting device (6) about a pivot axis near one end thereof, characterized in that at least one longitudinally extending recess (12) is provided in said longitudinal strip (4) along its entire length, wherein said recess is provided with a U-shaped cross-section made identical over the entire length of said recess, and wherein dimensions of said longitudinal strip (4) are adapted to dimensions of said longitudinal groove (3) .

A method according claim 6, wherein said longitudinally 7.

extending recess is made inside said longitudinal strip (4 ) by manufacturing said longitudinal strip (4) thorough a laminating process .

8. A method according to claim 6 or 7, wherein said longitudinal strip (4) is made of band steel.