GB2225218A

GB2225218A - Telescopic windscreen wiper

Info

Publication number: GB2225218A
Application number: GB8820854A
Authority: GB
Inventors: Mladen Ljubic
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-08-16
Filing date: 1988-09-05
Publication date: 1990-05-30
Also published as: GB8820854D0

Abstract

A windscreen wiper assembly comprises a mechanism for extending and retracting telescopic wiper arm member 7 whilst the wiper arm is being angularly oscillated. The wiper arm member 7 may be extended and retracted by means of a cable 28 wound around pulleys 27 which may be spread apart by cranks 15 actuated by connecting rod 18. The inner end of the arm member may act against the bias of spring 25 when being retracted. The wiper arm assembly may be angularly oscillated by drive shaft 12. The assembly may be locked in position below the windscreen with arm member 7 in the fully retracted position by means of electromagnet 24 and spring 33. <IMAGE>

Description

TELESCOPIC WINDSCREEN WIPER This invention relates to a telescopic windscreen wooer.

The windscreen wiper serves to provide transparency of an automobile windscreen during rainy and/or foggy weather. The wipers available at present function by wiping a surface which is a section of a circle area. Position and movement of a pair of wipers enables cleaning only oi a part of the windscreen surface, leaving the rest uncleaned, which may hinder the visibility.

According to the invention presented here a new telescopic windscreen wiper offer a possibility to wipe practically entire windscreen surface, significantly enhancing visibility and driving security. By means of a specially designed telescopic arm, comprising springs and cables assembly, the wiper attached to extendable part of the telescopic arm move in translatory motion across a windscreen, greatly improving efficacy of wiping although only one wiper is used.The most important feature is that during the transiatory motion tne wiper orientation relative to a windscreen surface remains unchanged regardless of its position on a wlndccreen, enabling a rectangular surface to be wipe. h wiped area can apnroxlmate the entire windscreen surface depending on the wiper dimensions. When not in use. bcrn tte wiper and the telescopic arm are in ccsitlon at the bottom ot a windscreen, minimal IV interfering with the drivers range of vision.

A more detailed principle of operation of this invention and a specific telescopic arm assembly are described in the toilowlng paragraph wttr reference to the accompanvina drawing.

Ail drawings are made in 1:1 scale except figures 1,9,10,14-17,20-22.

Figure 1 schematically illustrates windscreen wiper as a whole inclLitlng s views presented in Figures 2-5.

Figure 2 shows in detail ground-plan of a mechanism responsible for retraction and extension of a telescopic arm (view Q-S indicated in Figure li.

Figure 3 shows in detail ground-plan (seen from above) of the same as in Figure 2 (view A-S indicated in Figure 11.

Figure 4 shows in detail a side view of the telescopic arm, containing springs and cables assembly which enables retraction and extension of the telescopic arm (view C-D indicated in Figure 1J.

Figure 5 shows in detail ground-plan (seen frDm above of the same as in Figure 4 view J- indicated in Figure If.

Figure 6 and Figure 7 show main part and expendable part of the telescopic arm.

Figure 8 shows a joint (see element 8 in Figures 2,3,4 and 5i.

Figure 9 shows a slider (see element 9 in Figures 4 and 5).

Figure 10 shows a glider cube.

Figure 11 shows a stator of the telescopic arm assembly (see element 11 in Figures 2 and 4 Figure 12 shows rotating head (see element 12 in Figures 2 and 4).

Figures 13-16 show parts of a mechanism enabling retraction and extension of the telee - arm: slide-rod (Figure 13), slider (Figure 14t. cramp (Figure 15' and lock rod (Figure li.

Figure 17 shows a wiper connector (see element 17 in Figures 4 and 5), Figure 18 shows a connecting rod (see element 18 in Figures t and 3).

Figure 19 shows a hook (see element 19 in Figures 2 and 4).

Figure 20 shows a bar (see element 20 in Figures 4 and 5i.

Figure 21 shows a guide for guiding the etendabie telescopic arm see element 21 in Figures 4 and 5) Figure 2 shows a fixing plate (see element 22 in Figures 4 and 5).

Following elements are parts of the telescopic arm assembly indicated in Figures 2,3,4 and 23 = cables; 24 = electro-magnet; 25 = suspension spring; 26 = wiper; 27 = pulley; 28 = cable; 29 = distant spring; 30 = spring; 31 = tunnel; 32 = locking device; 33 = spring; 34 = profile; 35 = Bowden cable; 36 = screw; 37 = grease nipple; 38 = gasket; 39 = eye; 40 = pin.

The telescopic arm is fixed to a car-body in the middle of a windscreen base. Semi-rotatlona movement of the telescopic arm is driven by a rotational head (12), Translatory motion or a wiper across a windscreen is achieved by synchronous rotation and - shortening of the telescopic arm having a wiper attached to its extendable part (Figure 1). When a wiper is In extremely deflected position, a telescopic arm is fully extended. Movement of the telescopic arm from this position toward the opposite side of a windscreen causes its shortening by means of synchronous retraction of extendable part (7).The prin-iple o4 this ope-ation (see Figures 1-5) is as follows: movement of a connecting rod (18) forces two cramps 1', by means of leverage to spread a system of pulleys (27), thus straining a cable (26': and pu'ling 1 the extendable arm (7) inside the main telescopic arm (6). This shortening is balanced by the counteraction of a suspension spring (25). The length of the telescopic arm is at minimum (fully retracted) in a moment when wiper passes a central point of the windscreen surface which is followed by the movement of the telescopic arm forcing other parts of the assemblv to function in a reversed mode.Cosequently, the telescopic arm gradually lengthens as wiper continues to move toward the opposite side of the windscreen. Thus, the extension of tne telescopic arm depends an the position of the wiper on the windscreen. After reaching its position on the other side, the wiper reoeats the same movement in the opposite direction, untill the cycle is completed.

In order to establish a translatory motion of the wiper extension ano retraction of the telescopic arm should be synchronous with its semi-rotational motion across the windscreen.

This is easily achieved by choosing the proper dimensions of the elements 15 and 18 in the assembly design. The orientation of tne wiper is perpendcular with resoect to the direction of its translatory movement, and remains unchanged during operation, enablIng a rectangular surface to be wiped. This is performed bv a mutual action of the cables (;, distant spring (30) and wiper connector (17). Wiper is oppressed against the windscreen surface by action of the springs (31:) maintained on the bars (20).

The operation of the wiper is terminated by locking the whole assembly in fully retracted position of the telescopic arm bellow the windscreen. For this purpose an eiectro-magnet (24) is activated and, by means of spring and cable system t33) Indicated in Figures 2 and 3. pull up the glide rod (13.) carrying a system of pulleys (27) and cramps (15). In the moment when the telescopic arm is fully retracted and cramps (15) are parallel to it the cramps i151 are ejected (lifted by the spring 33) to a lock rod (16) and fixed by means of cams. Element J4 placed in a slide rod (13) is also lifted blocking the whole telescopic arm in this position.

The slide rod (13) is released from its footing and can rotate around the same axis as the rotating head (12). Movement of a rotating head continues untill a fully retracted telescopic arm, having the wiper fixed on one end and the slide rod/cramps assembly on the other placed bellow a windscreen.

Claims

1 A telescopic windscreen wiper comprising a telescopic arm with wiper attached to its extendable part, enabling by means of synchronous semi-rotational movement across a windscreen and retraction/extension of the telescopic arm, translatory motion of a wiper across a windscreen and a rectangular area to be wiped.

2 A telescopic windscreen wiper as claimed in Claim 1, wherein an assembly comprising a system of crapms, pulleys, springs and cables is provided to establish a functional dependence between semi-rotational motion of the telescopic arm and its retraction/extension.

3 R telescopic windscreen wiper as claimed in Claim 1 and Claim , wherein an assembly comprising a system of springs and cables is provided in order to keep the wiper in the same orientation during its motion across a windscreen.

4 A telescopic windscreen wiper as claimed in any preceding claim, wherein an assembly V is aranged in suct; a wav to lock. the telescopic arm in fully retracted position 1 order to place it bellow a windscreen.

5 A telescopic windscreen wiper as described herein with reference to Figures 1-2 ct the accompanving drawings.