GB2253135A

GB2253135A - A windscreen wiper arm

Info

Publication number: GB2253135A
Application number: GB9203565A
Authority: GB
Inventors: Maurice Journee; Jean-Pierre Jehannet; Philippe Sautour
Original assignee: Paul Journee SA
Current assignee: Paul Journee SA
Priority date: 1991-02-27
Filing date: 1992-02-20
Publication date: 1992-09-02
Anticipated expiration: 2012-02-20
Also published as: ITRM920123A0; DE4204125A1; FR2673151B1; IT1263205B; GB2253135B; FR2673151A1; GB9203565D0; ITRM920123A1

Abstract

A windscreen wiper arm, especially for motor vehicles, comprises a driven head (1), a blade carrier (3) articulated on the driven head and being of channel section, and springs (6, 6') interposed between the blade carrier (3) and the driven head (1), with ratchet means (30) carried by the springs and cooperating with an indexing means (16) comprising an element (17) projecting from the upper end of the driven head (1). The ratchet means ride over the projecting element (17) when the blade carrier (3) is swung upwards into a deployed position for changing a wiper blade, and are then held by the springs (6, 6') in that position so as to retain the deployed position of the blade carrier. <IMAGE>

Description

1 A WINDSCREEN WIPER ARM, ESPECIALLY FOR MOTOR VEHICLES This invention

relates to a windscreen wiper arm, especially though not exclusively for motor vehicles.

Conventionally, a windscreen wiper arm consists of a driven head with a blade carrier articulated on the driven head, the blade carrier comprising a channel shaped beam with the general cross sectional shape of an inverted U, which'.is extended by a bar at the outer or free end of the arm. At the outer end articulated.

of this bar a windscreen wiper blade is It is usual to provide, within the interior of the channel shaped beam, a spring means the main purpose of which is to urge the wiper blade against the surface of the glass to be wiped, with a predetermined pressure such that the wiper blade, and more particularly its wip2Lng strip, can rub on the glass with a constant pressure over the whole of its wiping movement.

Among other expedients it is known to provide such a spring means in the form of a coil spring (a tension spring) in which the endmost turns are extended in an upper branch and a lower branch. The free end of each of these branches is formed with an open hook by which the spring is hooked at one end on the blade carrier and at the other end on the driven head of the arm. For this purpose the driven head is provided with an anchor pin around which the hook of the lower branch is hooked, while the blade carrier has another anchor pin which is mounted between the wings of its channel section. The hook of the upper branch of the spring is hooked around this last mentioned anchor pin.

The wiper blade carried by the arm usually has a wiping strip which is in direct contact with the windscreen during wiping movement, and which therefore becomes worn. The 2 blade therefore needs changing periodically, and this is carried out by pivoting the blade carrier outwardly about the pivot pin of the driven head, so as to move the wiper blade away from the windscreen. In this position, referred to as a deployed position, the blade can then easily be removed from the arm and replaced with a new one.

H owever, although the wiper arm is in this way released from its engagement on the windscreen through the rubber wiping strip of the blade, when the blade is removed the arm can come into contact at its free end, which is generally of a hard material, against the windscreen with a danger of damage to the latter. Similarly, the arm can accidentally be released from its deployed position and be propelled by the spring means into violent impact against the windscreen.

It has been proposed, for example in the French published patent document FR 2 629 032A, to provide a positive stop means comprising a sliding finger carried by the driven head under the influence of a spring and arranged to engage in an aperture formed in the blade carrier, in such a way that during changing of the wiper blade, the blade carrier is held in its deployed position by cooperation of this finger with the aperture in the blade carrier. Although this arrangement gives satisfaction, it nevertheless has a number of drawbacks. For instance, it requires the provision of a number of elements which slide with respect to other elements, which can only increase the cost of the wiper arm. In addition, when the deployed position is reached, it is necessary to insert a tool through the aperture in the blade carrier, to release the finger so as to disengage the two parts from each other. This is rather an inconvenient way of restoring the windscreen wiper to its working position.

P 3 The present invention proposes to overcome the above drawbacks by proposing a windscreen wiper arm in which the deployed position is obtained in a simple and economical manner, while enabling the working position of the arm to be easily restored and without necessitating the use of either a multiplicity of additional elements or a mechanical operation involving use of a tool.

According to the present invention, there is provided:a windscreen wiper arm having a driven head and a blade carrier articulated on the driven head, with spring means comprising at least one spring connected between the driven head and the blade carrier, wherein the spring means carry ratchet means cooperating with indexing means comprising a projecting element extending from the driven head.

In changing a wiper blade in a windscreen wiper having a wiper arm according to the invention, the arm is automatically locked in the deployed position by the operator, and is able to revert to its working position by virtue of a simple reverse movement performed by the operator himself.

Various embodiments of the invention will now be described, by way of example only and with reference to the accompanying drawings, in which:

- Figure 1 is a view in longitudinal cross section of part of a windscreen wiper arm in accordance with the invention; - Figure 2 is a view in cross section taken on the line AA in Figure 1; - Figure 3 repeats part of Figure 1 but shows a blade carrier of the wiper arm in a first or partly deployed position; 7 f 1k 4 - Figure 4 is a view similar to Figure 3 but shows the blade carrier in a final or fully deployed position; - Figure 5 is again a view similar to part of Figure 1, but shows a wiper arm in a second embodiment of the invention in a working position; - Figure 6 shows the wiper arm of Figure 5 in a partly deployed position; - Figure 7 shows the same arm in a fully deployed position; - Figure 8 is another view similar to part of Figure 1 but shows a third embodiment of the invention; - Figure 9 is a perspective view showing a component of the wiper arm shown in Figure 8; - Figure 10 is another view similar to part of Figure 1, but shows a wiper arm in a fourth embodiment of the invention; - Figure 11 is a similar view to Figure 8, but shows a wiper arm in a fifth embodiment of the invention; and - Figure 12 is a perspective view of one component of the wiper arm shown in Figure 11.

Referring first to Figures 1 and 2, the windscreen wiper arm shown in these Figures has a driven head 1 formed with a bore 2 by which the driven head is mounted on a driving shaft (not shown) so as to be rotated by the latter in the usual oscillating motion. The driven head 1 is articulated to a windscreen wiper blade carrier 3, the structure of which is known pgr se in that it comprises a beam 4 of channel section, which is generally in the shape of an inverted U and which pivots about a pivot pin 5 arranged P J 1 transversely and spaced away from the bore 2. The pivot axis defined by the pin 5 is indicated by a phantom line in Figure 2. As is again known Rer se, the beam 4 has at its other end, not shown, remote from the end shown in the drawings and pivoted on the driven head 1, an extension bar portion which carries at its far end a windscreen wiper blade for wiping a glass surface such as a motor vehicle windscreen. The channel shaped beam 3 and the above mentioned bar may of course be integral with each other and may for example be a single component moulded in a suitable plastics material. In another variant, they may be made from a metal strip in such a way that each of the beam and the bar are reformed into a channel section in the form of an inverted U.

As shown in Figure 1, a spring means is interposed between the driven head 1 and the blade carrier 3, in such a way that the latter can exert a pressure on the wiper blade that is carried at its other end.

In the remainder of this description, and for easy understanding of the invention, the above mentioned spring means will be referred to in terms of two coil springs indicated at 6 and 61 in the drawings. It is however to be clearly understood that the invention is equally applicable to a wiper arm having only one spring. In Figure 1, the two coil springs 6 and 61 are mounted side by side and substantially parallel to each other, the spring 61 being of the same configuration as the spring 6. These two springs lie in a recess 7 formed in the driven head 1. Each spring has an upper branch 8, 81 respectively extending beyond its last turn, i.e. that situated on the left hand side in Figure 1, and a lower branch 9, 91 respectively projecting from the first turn on the right hand side of Figures 1 and 2. Each of the upper and lower i 6 branches 8, 81, 9 and 91 terminates in an open hook, indicated respectively at 10, 101, 11 and 111. These hooks are C-shaped as shown in Figure 1, with the open side of the C facing towards the associated branches of the spring. Each hook has a free end 12, 121, 13 and 131 respectively. The free ends 12 and 121 of the hooks 10 and 101 face towards the driven head 1, while the free ends 13 and 131 of the hooks 11 and 111 face towards the lower end of the channel shaped beam 4.

The upper hooks 10 and 101 embrace an anchor pin 14 which lies substantially parallel to the pivot pin 5 and is supported-by the wings of the U-shaped channel section of the beam 4. The lower hooks 11 and 111 are similarly hooked on a further anchor pin 15 which is mounted in the driven head 1, and which extends substantially parallel to the anchor pin 14 between the recess 7 and bore 2 of the head 1. A pivoting motion is thus applied to the blade carrier 3 by virtue of the springs being hooked on the anchor pins 14 and 15, with the springs tending to cause this pivoting movement to take place in an anti-clockwise direction with reference to Figure 1.

Still referring to both Figures 1 and 2, the driven head 1 has an indexing means 16 comprising a projecting element 17 extending from the face 181 of the driven head at the end of the latter remote from the bore 2. This end face 19 lies generally facing the anchor pin 14. The projecting element 17 lies between the pivot pin 5 and the anchor pin 14, and extends substantially parallel to the latter. It faces towards the free ends 12 and 121 of the anchor hooks 10 and 101 of the springs, but it may be formed along the whole of the width of the end face 181 of the driven head if desired.

0 1 i 7 The projecting element 17 may consist of a separate component secured to the end face 181, for example by being moulded on to the driven head 1 or attached by suitable fasteners such as screws. In the form shown in Figure 1, the projecting element 17 has a triangular cross section the base of which is coincident with the end face 181 of the driven head, with the apex 20 of the triangle facing generally towards the transverse plane containing the anchor pin 14. The apex 20 lies between upper and lower faces 18 and 19 respectively of the projecting element 17.

The springs 6 and 61 together carry ratchet means 30 for cooperation with the indexing means 16 carried by the driven head 1. Reference in particular to Figure 2 shows that this ratchet means 30 comprises a transverse element 40 which joins together the two free ends 12 and 12' of the upper hooks 10 and 101 of the two springs. The transverse element 40 is substantially parallel to the pivot pin 5, and lies at a distance d from the axis of the latter. The distance d is smaller than the distance D beween the apex (or front edge) of the projecting element 17 and the axis of the pivot pin 5.

Thus, as can be seen in Figures 3 and 4, when the windscreen wiper blade is being changed, a pivoting movement is applied to the blade carrier 3 so as to cause it to pivot about the pivot pin 5 in the direction of the arrow F1 in Figure 3. During this movement, the transverse element 40 comes into contact with the lower face 18 of the projecting element 17, along which it slides with continuing pivoting motion of the arm 3 until it reaches the front edge 20 of the element 17. This is the position in which it is shown in Figure 3, from which it can be seen that the anchor pin 14 is no longer in contact with the hooks 10 and 101 of the springs. The applied force for P 1 1 8 pivoting the blade carrier 3 is therefore greatly reduced, which facilitates the operation of changing a blade.

If the pivoting movement is now continued in the direction of the arrow F1 in Figure 3, the transverse element 40 passes over the front edge 20 of the projecting element 17, so that the pull exerted by the springs 6 and 61 causes it to slide up the upper face 19 of the element 17 until the spring hooks 10 and 101 once again fully engage the apchor pin 14. The springs are now holding the hooks 10 and 101 in a position in which they lock the blade carrier 3 in the outwardly inclined, or deployed, position shown in Figure 4, by cooperation with the projecting element 17 and anchor pin 14. With the blade carrier held in this position, the wiper blade can easily be changed without concern having to be had to holding the blade carrier in this position. The blade carrier can be released from this position and restored to its normal position in line with the driven head 1, simply by pushing it back in the opposite direction to the arrow Fl. This has the effect of causing the transverse element 40 to slide along the upper face 19, to pass around the edge 20 and to slide along the lower face 18, with the springs 6 and 61 returning it to its original position below the projecting element 17 as shown in Figure It will of course be understood that the transverse member 40 may be omitted between the two springs 6 and 61, and that at least one of the hook ends 12 and 121 may be situated at the same distance d as the transverse element 40 as described, so that it is these ends 12 and/or 121 that are then able to slide along the surfaces 18 and 19 of the projecting element 17.

IF 4 k 9 Referring now to Figures 5 to 7, these repeat substantially the same elements as those seen in Figures 1 to 4, and the same reference numerals are therefore used where appropriate. However in Figures 5 to 7, the hooks 10, 101 of the springs 6 and 61 engage against a sliding member 50 which is fitted in the hollow of the hooks and which constitutes the ratchet means. In this example the sliding member 50 is in the form of a tubular piece 60, the length of which is substantially identical to the distance b6tween the two wings of the U-shaped cross section of the beam 4. The member 50 is fitted around the anchor pin 14, but it will be noted that its internal diameter is larger than the outer diameter of the anchor pin 14, while its outer diameter is substantially equal to twice the radius of the inner face of the hooks 10 and 101, so that it fits snugly within these hooks as shown. The distance between the axis of the pivot pin 5 and the transverse plane which is tangent to the outer periphery of the member 50 closest to and therefore facing the end face 181 of the driven head 1, corresponds to the distance d described above.

Thus, and referring in particular to Figures 6 and 7, during the operation of changing the wiper blade, the pivoting movement of the blade carrier 3 in the direction of the arrow F1 causes the periphery of the tubular member 60 to bear against the lower surface 18 of the projecting element 17 until it reaches the front edge 20 of the latter, Figure 6. As the pivoting movement is continued, the member 60 slides on to the upper surface 19 of the element 17 to hold the blade carrier 3 in its fully deployed position with the wiper blade spaced away from the windscreen of the vehicle.

In the third embodiment shown in Figures 8 and 9, the sliding member 50 has a tubular body portion 70, which J again surrounds the anchor pin 14 and fits within the hooks 10 and 101 of the springs 6 and 61. The tubular body portion 70 is formed with a projecting, transversely extending lip 72, and also with retaining means 74 for attaching the sliding member 50 on the upper branches 8 of the springs 6 and 61. The lip 72 projects towards the transverse plane containing the axis of the pivot pin 5 and i.s substantially parallel to the latter, so that the distance dl between the free edge of the lip 72 and the axis of the pivot pin 5 is smaller than the distance D between the latter and the front edge 20 of the projecting element 17. The distance dl is also smaller than the distance D between the axis of the pivot pin 5 and the transverse plane which is tangent to the outer peripheral surface of the tubular body portion 70 of the member 50 where the tubular body is closest to the end face 181 of the driven head 1.

The retaining means 74 comprise two channel elements 77 and 78, lying substantially parallel to each other and spaced apart by a distance corresponding to the distance by which the two upper branches 8 and 81 of the springs 6 and 61 are themselves spaced apart. The cross section of each channel element 77, 78 corresponds substantially to the transverse cross section of the wire constituting the branches 8 and 81. The channel elements 77 and 78 are carried by a flat portion 79 which projects from the outer periphery of the tubular body portion 70 of the member 50, substantially parallel to the lip 72 as can be seen in Figure 9. The channel elements 77 and 78 clip on to the spring branches 8 and 81, and thus also act as spacers between the two springs.

Thus, during changing of a wiper blade, when the wiper arm is swung out in the direction of the arrow F1, the lip 72 7 7 I:

11 of the tubular member 70 slides along the lower surface 18, and passes over the front edge 20, of the projecting element 17 until the latter engages in the zone 80 lying between the lip 72 and the outer periphery of the tubular body portion 70, thus giving a partly deployed position of the blade carrier. If the pivoting movement is now continued in the direction of the arrow F1, the outer Cylindrical surface of the tubular body portion 70 now slides on the face 18, over the edge 20 and partly on. to the face 19, so as to reach a fully deployed position in which the projecting element 17 is now nested into the zone 81 shown in Figure 9, defined between the flat portion 79 and the cylindrical surface of the body portion 70.

In the fourth embodiment shown in Figure 10, the free ends 12 and 121 of the spring hooks 10 and 101 carry a transverse member 90 which is formed with two cylindrical sockets 90 and 911 of the same diameter as the free ends 12 and 121, which are fitted in these sockets so that they are joined together by the member 90. In the same way as has already been described above, the distance between the face of the transverse member 90 that faces towards the transverse plane containing the axis of the pivot pin 5 is smaller than the distance between the front edge 20 of the projecting element 17 and the axis of the pivot pin 5, so that once again the blade carrier 3 can be held in a deployed position for changing a wiper blade.

In the fifth embodiment shown in Figures 11 and 12, there is a transverse member 100 which is very similar to the transverse member 90 of Figure 10 and which similarly joins together the free ends 12 and 121 of the hooks 10 and 10' of the springs. However, the transverse member 100 has in addition a semi-tubular portion 102 which fits into the hooks 10 and 101, between the latter and the anchor pin 14.

J j 12 The invention is of course not limited to the embodiments described above, but includes all variants. In particular, the ratchet means may consist of the anchor pin 14 itself, sliding in grooves carried by the side wings of the channel section of the beam 4, and acting under the influence of the springs. In that case, the anchor pin 14 will slide on the surfaces 18 and 19 and over the front edge 20 of the projecting element 17 in order to give the required deployed position of the arm 3.

p 4 z 13

Claims

1. A windscreen wiper arm having a driven head and a blade carrier articulated on the driven head, with spring means comprising at least one spring connected between the driven head and the blade carrier, wherein the spring means carry ratchet means cooperating with indexing means comprising a p.rojecting element extending from the driven head.

2. A windscreen wiper arm according to Claim 1, wherein the spring means comprise two coil springs, each having an anchor hook engaging an anchor pin carried by the blade carrier, the said ratchet means comprising a transverse element connecting the free ends of the said hooks together.

3. A windscreen wiper arm according to Claim 2, wherein the said transverse element is a separate member carried on the free ends of the said hooks.

4. A windscreen wiper arm according to Claim 1, wherein the spring means comprises at least one coil spring having an anchor hook engaging an anchor pin carried by the blade carrier, the ratchet means comprising a sliding member carried by the spring or at least one of the springs.

5. A windscreen wiper arm according to Claim 4, wherein the sliding member is carried in the crook of at least one of the said anchor hooks.

6. A windscreen wiper arm according to Claim 4, wherein the sliding member is carried by the free end of at least one said anchor hook.

7. A windscreen wiper arm according to Claim 4, wherein the sliding member is a tubular member.

4P T V.

14

8. A windscreen wiper arm according..to Claim 7, wherein the tubular member surrounds the anchor pin.

9. A windscreen wiper arm according to any one of Claims 5, 7 or 8, wherein the tubular member includes a projecting transverse lip, and carries retaining means for engaging the spring means.

V0. A windscreen wiper arm according to any one of the preceding Claims, wherein the said-transverse element includes a semi-tubular portion fitting in the crook of the anchor hooks of the springs.

11. A windscreen wiper arm substantially as described in the foregoing description with reference to Figures 1 to 4, or Figures 5 to 7, or Figures 8 and 9, or Figure 10, or Figures 11 and 12, of the accompanying drawings.

0