AU617308B2

AU617308B2 - Lockback device for the wiper arm of a windscreen wiper

Info

Publication number: AU617308B2
Application number: AU13553/88A
Authority: AU
Inventors: Peter Mower
Original assignee: Trico Ltd
Current assignee: Trico Ltd
Priority date: 1987-03-25
Filing date: 1988-03-24
Publication date: 1991-11-28
Anticipated expiration: 2008-03-24
Also published as: GB2203934A; AU1355388A; GB8707135D0; GB2203934B; BE1001071A5; DE3809966A1; GB8807017D0; JPS63305058A

Description

4 COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952-69 COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged; Aceped Published: Priority Rlelated Art Name of Applicant: Address of Applicant: Act~al Inventor; Address for Service: TRICO-FOLBERTH LIMITED Great West Road, Brentford, Middlesex TW8 9HP, England PETER MOWER EDWD. WATERS SONS, 50 QUEEN STREET, MELBOURNE, AUSTRALIA, 3000.

Complete Specification for the Invention entitled: LOCKBACK DEVICE FOR THE WIPER ARM OF A WINDSCREE1N WIPER The following statement Is a full description of W'vention, Including the best mathod of per' 4rming It known to us LOCKBACK DEVICE FOR THE WIPER ARM OF A WTNDSCREEN WIPER This invention relates to a lockback device for the wiper arm of a windscreen wiper.

There has become a tendency at the present time to fit the windscreen wiper drive spindle in a slot in the bodywork of a vehicle, so that, when the windscreen wiper is parked, it is no longer on view, With this type of arrangement, the usual lockback for the wiper arm, which is provided by over centre action of the arm spring cannot be used since otherwise the edges of the slot would be fouled. Nevertheless it is desirable to lift the windscreen wiper blade from the screen both for 1 i5 purposes of changing the blade and for the purposes of cleaning tiie windscreen, Alec this lockback has hbPn required for assembly of the wiper system initially.

Therefore there have been proposed devices for locking back the windscree, wiper arm in a somewhat raised position but these devices have been relatively complicated or consisted of parts which require to be kept separately to the windscreen wiper arm and e therefore are easily lost, 25 The present invention seeks to provide a lockback device doe o for the arm of a windscreen wiper which is of relatively simple construction, has no loose parts and can be simply operated.

According to the invention, there is provided a lockback device for the arm of a windscreen wiper comprising an arm member, e retainer carrying the arm member, an arm head for attachment to e drive spindle and pivotted to the retainer, and a spring acting between the arm head and the retainer in a direction to urge the arm towaros the windscreen with which the wiper is intended to be used, the lockback device comprising a shoulder on the retainer and a slider moveable in the head between a first position in which it is positioned in the line of movement of the shoulder to limit the pivotting movement between the arm head and retainer and a second position in which it is clear of the shoulder on the retainer and permits full pivotting of the head and retainer.

Preferably the retainer, at its end pivotted to the arm head, is of channel shaped section so as to receive the arm head in the channel thereof, the shoulder being o formed on the sidewall of the channel of the retainer "and the slider is arranged to slide transversely relative to the arm.

00 0 a a If desired Lhe slider may be spring biassed towards its second position.

The invention will now be described in greater detail, by way of example, with reference to the drawings, in which: Figure 1 is a perspective view of a slider used in one form of lockback device in accordance with the invention; Figure 2 is a perspective exploded view of a lockback device using the slider shown in figure 1; Figure 3 is a side view of a lockback device according to figures 1 and 2; Figure 4 is a plan view from underneath showing the arrangement of the slider in the arm head; Figure 5 is a diagrammatic sectional view through a to. i A r 3 variation of the lockback device of figures 1 to 4; Figure 6 is a sectional view taken on the line VI-VI of figure 5, and 7U~ 44 44 0 0 44 ]0 4 4 j i a 00 t 440 5 4 4 4 4 444 4r 4 4444,t Figure 7 is a view similar to figure 6 but showing a different form of lockback device in accordance with the invention.

Referring firstly to figures 1 to 4, there is shown a part of a windscreen wiper arm 1, including a retainer 2 which carries an arm member (not shown) and an arm head 3 pivotted to the retainer 2 by means of a pivot pin passing through both the retainer 2 and the arm head 3 15 and being peened over at its headless end in the form of a rivet, A spring which is used for urging the arm towards the windscreen is indicated diagrammatically at A shoulder 10 is formed on the retainer 2 so as to lie radially of the pivot pin 5. A slider 12, sliding in a slot or slots 14 in the arm head 3 is moveable transversely to the head. It is moveable between between a first position in which a stop 16 on the slider 12 can engage behind the shoulder 10 and a second position in which the stop 16 lies outside the path of the shoulder 10 thus giving free pivottjin movement of the retainer 2 relative to the head 3. The slider 12 basically comprises a trifurcated member having two outer limbs 17 and 18 parallel to each other and a middle limb 19 which is bowed at right angles to the remaining two limbs 17 and 18 so as to provide a frictional.effect in the slot(s) 14 in the head 3. The slider 12 is formed with two stop elements one of which (<20 is intended to retain the slide in the slot(s) 14 in the head 3 and the other of which (16) is intended to engage behind the shoulder 10 on the retainer 2, as will be described in more detail hereafter, The end~ of the slider 12 is bent upwardly from the plane of the outer two limbs 17 and 18, and acts both to limit movement of the alider 12 and as an operating handle 22 as will also be described hereafter.

The assembly and operation of the lockback device as described above will now be considered: Prior to aFssembly of the parts 2 and 3 of the arm 0together, the slider 12 is slid into its slot 14, Thereafter head and retainer parts of the arm are 0assembled in the usual way using the pivot pin 5, it will be seen, that, due to the fact that the retainer2 0:00.:ex~ends around the outside of the head 3 and radially further outward of the pivot than the end of the slots 14-, once the arm has been assembled the slider 1,2 will be captivated in the slots 14 and thus be prevented from being lost, in order to lock the arm in the lockback position, the retainer 2 is pivotted about the arm head 3 in a direction away from the windscreen (anticlockwise in figure 3) until the shoulder 10 passes the slot 14.

With the retainer 2 and arm head 3 held in this position, the slid(er 12 is pulled out using the handle portion 22, sothat the retaining stop 16 is positioned behind the shoulder 10 of the retainer 2. The retainer 2 is then allowed to pivot back under the acion of the spring 7 whereupon, when the shoulder 10 engages the stop 16 in the slider, this will prevent it from pivotting any further and will maintain the arm in a position with the windscreen wiper blade spaced from the windscreen, To unlock the lockback device, the retainer 2 is again pulled back in an anticlockwise direction against the action of the spring 7 so as to move the shoulder away from the retaining stop on the slider, thus releasing the slider 12. The slider 12 can then be pushed back into the arm head 3 so that the retaining stop 16 is moved out of the path of the shoulder and, on release of the retainer, the pivotting of the retainer 2 relative to the head 3 is unrestricted so that the windscreen wiper blade will be returned to the windscree for operation.

Figures 5 and 6 show a modified arrangement in which the slider 12 is urged to its non-operative position by means of a compression spring 30, This spring 30 acts between the tlider 12 and one side of the arm head 3, the slider 12 being provided with a projection 32 on which the compression spring 30 is located.

With this embodiment, the retainer 2 must be released while the slider 12 is held out to achieve iockback, the force of the shoulder 10 acting on the retaining stop 16 of the slider being sufficient to counteract the bias of the compression spring 30, In order to release the wiper arm, the retainer 2 is pulled back, releasing the slider 12 which is then moved by the spring 30 back into its non-operative position. When the retainer 2 is again released, full pivotting can be carried out, In a further version of the arrangement shown in figure 7, this spring 30 is again omitted and the necessary friction for the slider 12 is provided by means of a rubber or soft plastics insert 40 which engages the slider 12, thus doing away with the necessity for the bowed central arm 19 of the slider 12, In this way the slider 12 can be made as a solid sheet member, 6 It will be appreciated that various modifications may be made to the above described embodiments without departing from the scope of the invention. For example, the slider can be of any suitable shape, such as round, the slider being provided with the appropriate projections as stops for engagemeic with the shoulder.

0 o a I t6 s: r (S <l

Claims

1. A lockback device for the wiper arm of a windscreen wiper comprising an arm member, a retainer carrying the arm member, an arm head for attachment to a drive spindle and pivotted to the retainer, and a spring acting between the arm head and the retainer in a direction to urge the arm towards the windscreen with which the wiper is intended to be used, wherein the lockback device comprises a shoulder on the retainer and a slider moveable in the head between a first position in which it is positioned in the line of movement of the shoulder to limit the pivotting movement between the arm head and retainer and a second position in which it is clear of the shoulder on the retainer and permits full pivo Ling of the head and retainer.

2. A lock back device as claimed in claim 1, wherein the retainer, at its end pivotted to the arm head, is of channel shaped section so as to receive the arm head in the channel thereof, the shoulder being formed on the sidewall of the channel of the retainer and the slider is arranged to slide transversely relative to the arm. 3, A lockback device as claimed in claim 1 or 2, wherein the slider slides in one or more slots in the arm head, 4, A lockback device as claimed in claim 3, wherein the slider is a trifurcated member having two outer limbs paral el to eacho ther and a middle limb which is bowed -arght a-gl eo-t-e- the remaining two limbs so as to provide a frictional effect in the slot in the head, M(S 8 A lockback device as claimed in claim 4, wherein the end of the slider away from the free ends of the limbs is bent upwardly from the plane of the outer two limbs and acts as an operating handle

6. A lockback device as claimed in claim 3, 4 or wherein the slider is formed with two stop elements one of which is intended to retain the slider in the slot(s) in the arm head and the other of which is intended to engage behind the shoulder cn the retainer, S. 7, A lockback device as claimed in claim 1 or 2, S4 wherein the slider is spring biassed towards its second ,S .position, S6 A luckback device for the wiper arm of a windscreen wiper substantially as described herein with reference to the drawings, DATED this 23rd day of March 1988. TRICO-FOLBERTH LIMITED EDWD. WATERS SONS PATENT ATTORNEYS QUEEN STREET MELBOURNE. VIC. 3000.