GB1591310A

GB1591310A - Windscreen wipers

Info

Publication number: GB1591310A
Application number: GB4985976A
Authority: GB
Original assignee: Trico Ltd
Current assignee: Trico Ltd
Priority date: 1976-11-30
Filing date: 1976-11-30
Publication date: 1981-06-17
Also published as: DE2753252A1; ES464607A1; FR2372055B3; FR2372055A1; IT1090250B; BE861119A

Description

(54) IMPROVEMENTS RELATING TO WINDSCREEN WIPERS (71) We, TRICO-FOLBERTH LIMITED, a British Company, of Great West Road, Brentford, Middlesex, TW8 9HP, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement : Motor vehicles when new are fitted with windscreen wiper assemblies selected by the vehicle manufacturer from a considerable range of designs of wiper assembly offered by accessory manufacturers. A wiper assembly commonly consists of a wiper blade unit connected to the outer end of a wiper arm, the inner end of the arm being mounted on a shaft which can be driven with an oscillating action.

The effective life of a wiper blade unit is only a fraction of the life of the vehicle.

Consequently the user of a vehicle wishes to replace the blade unit from time to time. The user may not necessarily wish to replace the blade unit by one identical with that originally fitted to the vehicle. A different type of blade unit may be more effective, more readily available, or cheaper. In particular the public will benefit from lower prices consequent from large-volume production, if a blade unit made for the replacement market can be used in association with a wide range of existing wiper arms.

Problems arise, however, over providing for connection between the replacement blade unit and the existing wiper arm.

The present invention is concerned with replacement blade units to be fitted to wiper arms of the general kind described in British Patent No. 1 212 337. The arms of this general kind have been developed and have appeared in practice comprising a metal bar and a one piece plastics arm-to-blade connector fixed on the outer end of the bar. The outer end of the connector is bifurcated by a parallel sided slot with a circular widening at its inner end. The connector is also formed with a tongue having lateral resilience which serves as a latch in a wiper arm and blade assembly. Such an arm is hereinafter referred to as "a wiper arm of the kind specified".

Hitherto, such an arm has been used with a blade unit including a yoke which is of channel section with a window in the web and having a bar extending transversely between the side flanges of the yoke, the bar having a pair of diagonally opposed flat surfaces.

When the arm and this blade unit are in assembly, the blade lies beneath the arm.

Recently there has been an increasing use by motor vehicle manufacturers of windscreen wiper blades and arms of the general kind described in British Patent No. 1 254 109, that is to say, of the kind in which a blade unit has a mounting pin which projects outwards from a side thereof. The blade unit is mounted on a wiper arm by inserting the pin into an aperture of a bearing through the side of the arm so that the blade can lie alongside the arm, with freedom to pivot about the pin axis. A blade unit of this kind cannot normally be fitted directly to wiper arms of the kind described in British Patent No. 1212337.

An object of the present invention is to provide an adaptor for the purpose of coupling a blade unit of the kind described in Patent No. 1 254 109 to a wiper arm of the kind specified, to form an operable combination. This purpose is hereinafter referred to as "the purpose hereinbefore described".

Accordingly the present invention resides in an adaptor, for the purpose hereinbefore described, comprising a pair of parallel spaced walls joined rigidly by a pin extending from side to side between the adaptor walls, and by a transverse member spaced from the pin, there being aligned holes in the adaptor walls defining end portions of a receptor, and there being a spring latch supported by the adaptor to encroach on the receptor, the adaptor pin constituting a coupling for the wiper arm connector, the transverse member providing an abutment face for engagement with the wiper arm connector to resist disengagement thereof from the adaptor pin, and the spring latch engaging in a circumferential groove in the mounting pin of the wiper blade to retain the mounting pin in the receptor when the adaptor is in assembly with the wiper arm and blade.

Preferably the adaptor comprises a pair of parallel spaced walls joined rigidly by a web, by a transverse member spaced from the web, and by a pin extending from side to side between the adaptor walls, the web having a passage which pierces the adaptor walls and has itself an opening between them, and there being a spring latch supported by the adaptor to encroach on the passage at the opening in the web, the adaptor pin constituting a coupling for the wiper arm connector, the transverse member providing an abutment face for engagement with the wiper arm con nector to resist disengagement thereof from the adaptor pin, and the spring latch engaging in a circumferential groove in the mounting pin of the wiper blade to retain the mounting pin in the passage when the adaptor is in assembly with the wiper arm and blade.

Two examples of adaptor according to the present invention are shown in the accom panying drawings, and also a wiper arm of the kind specified.

In the drawings: Figure 1 is a side elevation of the outer end portion of the wiper arm with the connector; Figure 2 is a side elevation showing a first adaptor mounted on the connector of the arm; Figure 3 is a longitudinal section through the adaptor of Figure 2, on the line III--III in Figure 4; Figure 4 is a plan of the adaptor of Figure .2; Figure 5 is an end elevation of the adaptor, as seen from the direction of the arrow A in Figure 3; Figure 6 is an enlarged central longitudinal cross-section of a second, preferred, adaptor, parts corresponding to parts in the adaptor of Figures 2 to 5 having the same reference numerals with the suffix "a" added; Figure 7 is an enlarged end elevation of the adaptor of Figure 6, seen in the direction of arrow B; Figure 8 is an enlarged view of the spring used in the preferred adaptor; and Figures 9 and 10 are end and plan views, respectively, of the blade unit used with the adaptor.

Referring to the drawings, particularly to Figure 1, the wiper arm comprises a metal bar 1, fixed on the outer end of which is a one piece plastics wiper arm-to-blade connector 2. The connector is bifurcated at its outer end by a parallel-sided slot 3 with a circular widening 4 at its inner end. Adjacent to the widening 4 and rearward of its extends a laterally resilient tongue 5 which engages with either example of adaptor hereinafter de scribed. An abutment face 5b adjacent to the tongue 5 is effective during the engagement.

The adaptor 10 in Figures 2 to 5 consists of a a moulded hollow plastics body comprising a pair of parallel spaced side walls 11, 12 rigidly joined by a web 13 and by a transverse member 14 which are spaced from each other, there being an opening 15 between them.

The web 13 and the parts of the adaptor side walls 11, 12 which the web joins are pierced by a straight passage 18 at right angles to the side walls. The passage is cylindrical excepting centrally between the side walls 11, 12 where there is a side opening inwards of the adaptor. End portions of the passage constitute aligned holes in the side walls.

A cylindrical coupling pin 22 spaced from the web 13 and member 14 extends from side to side between the side walls 11, 12. This pin 22 may be of plastics material integrally moulded with the side walls, or may be a rivet extending through aligned holes in the side walls.

The adaptor supports a spring latch 20, conveniently by means of the pin 22 as shown, the latch being of substantially Sform longitudinally of itself one end portion 22 of the latch embracing the pin and thereby being retained. The other end portion of the latch 20 is of cantilever form which is presented to lie in a groove 19 in web 13 and encroach on the passage 18 by extending transversely across it.

The diameter of the latch portion 20 when backed up by the pin 22 is substantially equal to the width of the parallel-sided slot 3 in connector 2, and can enter the slot 3 when the connector is pushed on to the portion 20, and can pivot with the pin 18 in the widening 4 relatively to the connector about the pin axis.

The distance between the abutment face 5b of the connector and the widening 4 of the slot 3 corresponds with the distance between an abutment face 14b of the adaptor and the latch portion 20 backed up by the pin 22.

Between the pin 22 and the outer end of the adaptor, i.e. adjacent to the side of the pin 22 remote from the member 14, each of the side walls 11, 12 has a respective internal rounded protuberance 16, 17 for engaging in the connector slot 3.

In order to assemble the adaptor 10 and the arm connector 2, the arm is held in the attitude shown in Figure 1, while the adaptor is to the right of it, in an attitude rotated anti-clockwise about 20 from the attitude shown in Figure 2. The adaptor is then moved to the left, so that the pin 22 embraced by -latch portion 20 enters the slot 3. Movement of the adaptor to the left is continued until the pin 22 and the embracing latch portion 20 reach the widening 4 at the inner end of the slot 3. Thereupon, the adaptor 10 is rotated clockwise through about 20 , so that the resilient tongue 5 on the arm connector 2 passes downwards through the opening 15, past the right-hand or abutment face 14b of the transverse member 14, and latches beneath the transverse member 14. At the same time, the protuberances 16, 17 ride over the side faces of the connector 2, and enter the slot 3. The side walls 11, 12 flex slightly while this is happening. The protuberances 16, 17 resist unintended rotation of the adaptor 10 in opposite senses, thereby preventing rattling in the assembled condition. The tongue 5, by latching with the transverse member 14, prevents anti-clockwise rotation of the adaptor relatively to the connector in Figure 2.

Furthermore, latching of the tongue 5 with the member 14 not only maintains the abutment faces 5b, 14b adjacent to each other, thereby preventing withdrawal of the pin 22 from the widening 4 through the slot 3, but also maintains the latch portion 20, backed up by the pin 22, adjacent to the left-hand extremity of the widening 4 as viewed in Figure 1, thereby preventing movement of the adaptor 10 to the left of the connector 2 as viewed in Figure 2. The adaptor can, however, be released from the arm connector 2, by flexing the tongue 5 to the right, and then rotating the adaptor 10 anti-clockwise through about 20 to overcome protuberances 16, 17, and removing the adaptor to the right.

The blade unit, shown in Figures 9 and 10 of the drawings, is of a known kind, available on the market, and described in our British Patent No. 1 254 109 mentioned above.

Projecting from one side of the harness 26 of the blade unit there is a cylindrical mounting pin 27, having a slightly tapered tip 28, and a circumferential groove 29. The length of the pin is somewhat greater than the width of the adaptor 10.

The preferred form of adaptor, shown in Figures 6 and 7, has in general the features of the first adaptor. Only the variants will be described. Protuberances 16a, 17a on each side wall 1 la, 12a adjoin the outer end of the adaptor and are of ridge instead of rounded form. Spring latch 20a is of substantially Uform longitudinally of itself and is retained by friction in a recess 24 in the web 13a. One limb 23 of the U is however longer than the the limb 25. The limb 23 encroaches on the passage 1 8a by extending transversely across the passage. The limb 23 projects beyond the side walls of the adaptor to enable the limb to be manipulated. The short limb 25 terminates in an outwardly bent end which engages one wall of the recess 24. Details of the latch 20a can be seen in Figure 8.

The preferred adaptor is assembled with the arm connector 2 by the procedure described with preference to the first adaptor.

Either form of adaptor can be assembled with the blade unit, before or after assembling the connector and adaptor, by pushing the pin 27 of the blade unit into one end of the passage 18 or 18a. The tapered tip 28 of the pin 27 flexes spring latch 20 or 20a upwards.

The pill 27 can then enter into the passage 18 or 1 8a until a shoulder on the pin 27 engages one external face of the side wall 11 la) or 12 (12a) as the case may be. At the same time the latch 20 or 20a engages in the circumferential groove 29 on the pin 27. The blade unit is thus pivotally connected to arm 1. The blade unit can be released from the adaptor 10, after the adaptor has been released from the arm connector 2, by pressing upwards on the part of the latch 20 which is exposed at the outer end of the adaptor, to the right of Figure 2, or, in the preferred adaptor, by pressing upwards on the exposed end of the limb 23, whereupon the blade unit can be displaced sideways to withdraw the pin 27 from passage 18 or 18a.

It will be apparent that, in the assembled condition, any tendency for the adaptor 10 to shift to the right in Figures 1 and 2, relatively to the arm, is entirely prevented by engagement of the abutment faces 5b, 14b. Corresponding remarks apply to the preferred form of adaptor. There is thus firm engagement of surfaces of considerable area to resist such forces as may be caused by centrifugal action when the wiper arm is oscillating.

WHAT WE CLAIM IS: 1. An adaptor for the purpose hereinbefore described, comprising a pair of parallel spaced walls joined rigidly by a pin extending from side to side between the adaptor walls, and by a transverse member spaced from the pin, there being aligned holes in the adaptor walls defining end portions of a receptor, and there being a spring latch supported by the adaptor to encroach on the receptor, the adaptor pin constituting a coupling for the wiper arm connector, the transverse member providing an abutment face for engagement with the wiper arm connector to resist disengagement thereof from the adaptor pin, and the spring latch engaging in a circumferential groove in the mounting pin of the wiper blade to retain the mounting pin in the receptor when the adaptor is in assembly with the wiper arm and blade.

2. An adaptor as claimed in claim 1, in which there is also a web extending between the adaptor walls, and the aligned holes in the adaptor walls are end portions of a passage which passes through the web, the spring being situated in a recess in the web communicating with the passage.

3. An adaptor for the purpose hereinbefore described, comprising a pair of parallel spaced walls joined rigidly by a web, by a transverse member spaced from the web, and by a pin extending from side to side between the adaptor walls, the web having a passage which pierces the adaptor walls and has itself an opening between them, and there being a spring latch supported by the adaptor to encroach on the passage at the opening in the web, the adaptor pin constituting a coupling

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. beneath the transverse member 14. At the same time, the protuberances 16, 17 ride over the side faces of the connector 2, and enter the slot 3. The side walls 11, 12 flex slightly while this is happening. The protuberances 16, 17 resist unintended rotation of the adaptor 10 in opposite senses, thereby preventing rattling in the assembled condition. The tongue 5, by latching with the transverse member 14, prevents anti-clockwise rotation of the adaptor relatively to the connector in Figure 2. Furthermore, latching of the tongue 5 with the member 14 not only maintains the abutment faces 5b, 14b adjacent to each other, thereby preventing withdrawal of the pin 22 from the widening 4 through the slot 3, but also maintains the latch portion 20, backed up by the pin 22, adjacent to the left-hand extremity of the widening 4 as viewed in Figure 1, thereby preventing movement of the adaptor 10 to the left of the connector 2 as viewed in Figure 2. The adaptor can, however, be released from the arm connector 2, by flexing the tongue 5 to the right, and then rotating the adaptor 10 anti-clockwise through about 20 to overcome protuberances 16, 17, and removing the adaptor to the right. The blade unit, shown in Figures 9 and 10 of the drawings, is of a known kind, available on the market, and described in our British Patent No. 1 254 109 mentioned above. Projecting from one side of the harness 26 of the blade unit there is a cylindrical mounting pin 27, having a slightly tapered tip 28, and a circumferential groove 29. The length of the pin is somewhat greater than the width of the adaptor 10. The preferred form of adaptor, shown in Figures 6 and 7, has in general the features of the first adaptor. Only the variants will be described. Protuberances 16a, 17a on each side wall 1 la, 12a adjoin the outer end of the adaptor and are of ridge instead of rounded form. Spring latch 20a is of substantially Uform longitudinally of itself and is retained by friction in a recess 24 in the web 13a. One limb 23 of the U is however longer than the the limb 25. The limb 23 encroaches on the passage 1 8a by extending transversely across the passage. The limb 23 projects beyond the side walls of the adaptor to enable the limb to be manipulated. The short limb 25 terminates in an outwardly bent end which engages one wall of the recess 24. Details of the latch 20a can be seen in Figure 8. The preferred adaptor is assembled with the arm connector 2 by the procedure described with preference to the first adaptor. Either form of adaptor can be assembled with the blade unit, before or after assembling the connector and adaptor, by pushing the pin 27 of the blade unit into one end of the passage 18 or 18a. The tapered tip 28 of the pin 27 flexes spring latch 20 or 20a upwards. The pill 27 can then enter into the passage 18 or 1 8a until a shoulder on the pin 27 engages one external face of the side wall 11 la) or 12 (12a) as the case may be. At the same time the latch 20 or 20a engages in the circumferential groove 29 on the pin 27. The blade unit is thus pivotally connected to arm 1. The blade unit can be released from the adaptor 10, after the adaptor has been released from the arm connector 2, by pressing upwards on the part of the latch 20 which is exposed at the outer end of the adaptor, to the right of Figure 2, or, in the preferred adaptor, by pressing upwards on the exposed end of the limb 23, whereupon the blade unit can be displaced sideways to withdraw the pin 27 from passage 18 or 18a. It will be apparent that, in the assembled condition, any tendency for the adaptor 10 to shift to the right in Figures 1 and 2, relatively to the arm, is entirely prevented by engagement of the abutment faces 5b, 14b. Corresponding remarks apply to the preferred form of adaptor. There is thus firm engagement of surfaces of considerable area to resist such forces as may be caused by centrifugal action when the wiper arm is oscillating. WHAT WE CLAIM IS:

1. An adaptor for the purpose hereinbefore described, comprising a pair of parallel spaced walls joined rigidly by a pin extending from side to side between the adaptor walls, and by a transverse member spaced from the pin, there being aligned holes in the adaptor walls defining end portions of a receptor, and there being a spring latch supported by the adaptor to encroach on the receptor, the adaptor pin constituting a coupling for the wiper arm connector, the transverse member providing an abutment face for engagement with the wiper arm connector to resist disengagement thereof from the adaptor pin, and the spring latch engaging in a circumferential groove in the mounting pin of the wiper blade to retain the mounting pin in the receptor when the adaptor is in assembly with the wiper arm and blade.

for the wiper arm connector, the transverse member providing an abutment face for engagement with the wiper arm connector to resist disengagement thereof from the adaptor pin, and the spring latch engaging in a circumferential groove in the mounting pin of the wiper blade to retain the mounting pin in the passage when the adaptor is in assembly with the wiper arm and the blade.

4. An adaptor as claimed in claim 3, in which the spring latch is retained by the adaptor pin and presents a cantilever portion of itself which extends transversely of the passage.

5. An adaptor as claimed in claim 3, in which the spring latch is of substantially S-form longitudinally of itself, one end portion of the latch embraces the adaptor pin and is thereby retained, and the opposite end portion of the latch extends transversely of the passage.

6. An adaptor as claimed in claim 3, in which the passage opening disposed between the adaptor walls opens in a recess in the web, and the recess retains the spring latch.

7. An adaptor as claimed in claim 6, in which the spring latch is of substantially U-form longitudinally of itself and is retained by friction in the recess, one limb of the U-form extending transversely of the passage.

8. An adaptor as claimed in any of claims 3 to 7, in which the adaptor walls have protuberances disposed adjacent to the side of the adaptor pin remote from the transverse member, for resisting rotation relative to the connector in opposite senses when the adaptor and connector are in assembly.

9. An adaptor for the purpose hereinbefore described, and constructed substantially as described with reference to Figures 2 to 5 or Figures 6 to 8 of the accompanying drawings.