US3399418A - Window or windscreen wiper mechanisms - Google Patents

Description

l 1968 E. D. WYNN ETAL ,3

WINDOW OF WINDSCREEN WIPER MECHANISMS Filed June 13, 1966 Edward Donald .Cheltenham, an d Charlies Geoffrey .Longford, Quedgeley, near Gloucester, England, as-

"signers to Wynn Development Limited, Ch'eltenl anj,

England Filed June13, 1966, Ser. No. 557,143

Claims priority, applicationGreat Britain, Aug." 6, 1965,

7 Claims. (Cl. 15250.24) r i ABSTRACT-:OETHE DISCLOSURE-f Awiper assembly which acarriage for a wiper blade is i'e'cip'rocated by means'of a link "Inemberhidgedto said carriage and to a bracket r'nemb'er connected' 'to an endless belt passinga'round two sprockets; The connection between'the bracket member and belt is achieved by providing projecting means extending'outvvard from the bracket member and gripping the belt;

' The present invention is an improvement in orm odification of that forming the subject of our" prior U S'. Patent'No. 3,042,954 which fis concerned'with window or windscreen wiper mechanism 'in'cluding'a carriage slidable to and fro between, guides and carrying a wiper blade supporting arm, an endless belt passing around spaced pulleys,'one d'f vvhich is drivenby means ofian electric motor or other driving mechanism t'o impart a unidirectional movement to 'said belt and means connect: ing said belt to the carriage to impart a straight line motionto the wiperbla'de'or blades. p The earlier construction included aclip or pad of arduate-shape which was attached t'd'the belt, the radius of the arc approximating to the radii of thepulleys around which the belt and its associated, clipfor pad had to pass.

Such a construction was particularly, suitable for use with a belt of V'shape in cross-section but'was "applicable to belts of other shape, perhapszto' a 'le'sser'extent. i

The present invention is concerned with the connection of the carriage to the belt, the device in accordance with the present invention having been specially designed for use with belts of the flat or power grip type, the latter comprising a generally flat belt formed with integral spaced inwardly directed transverse projections or ribs for entering spaced notches in the pulleys to prevent belt slip.

In the construction disclosed by the specification and drawings of the prior patent, the belt was connected to the carriage by means of a connecting rod or link, but it is within the scope of the invention to employ any suitable means such as for example a form of scotch yoke engaged by a laterally projecting pin or its equivalent mounted on the belt.

The chief object of the invention is to evolve a method of connection between a belt and some other component which will not impair the natural flexibility of the belt or interfere with the passage of the belt and its associated connection around the pulleys or rollers even though they may be of small diameter.

The invention consists broadly in forming the belt with a tuck at the connecting point, the tuck being directed outwardly of the belt and enclosing a pin or other driving member.

It will be appreciated that when the invention is applied to a belt formed with equally spaced projections or ribs for entering notches in the pulleys, the provision of a tuck in the belt must not under any circumstances vary the longitudinal spacing of the projections in the vicinity of the tuck and consequently it is proposed ac- Patented sar -v 9 cording to a further feature of the invention to soform the tuck that. the spacing of the projections immediately below the tuck are equal to the spacing of the notches in'the pulleys or are exactly equal to twice the spacing of the notches in the pulleys to ensure that when that partofthe belt ,passes over a pulley the projections .will enter the notches without difliculty. e

Referringto the accompanying drawings: I I

FIGURE 1 is a longitudinal section on the line A-B FIGURE 2 of one formof driving pad in accordance with the invention and its associated belt; J 1 7 FIGURE 2 is a transverse section on the line C-D in FIGURE 1; I g FIGURE 3 is a section on the line E-Fin FIGURE 4 illustrating a modified construction; y, I I

FIGURE 4 is a section on the line G;H in FIGURE ,3; FIGURE 5 is a .plan view of the driving pad illustrated in FIGURES 3 and 4; and v v FIGURE 6 is a sectional side elevation of a modified construction.

As disclosed in applicants above-identified US. patent, a straight line reciprocal wiper motion is achieved by means of an endless belt passing over two spaced pulleys, and driven by means of an electric motor or the like connected with one of the pulleys. A carriage for the Wiper blade is provided which is permanently connected with the endless belt by means of a link hinged at one end to the belt and at the other end to the carriage. Therefore, upon driving one of the pulleys, the end of the link hinged to the belt travels in an endless path and imparts reciprocal movement to the carriage and therefore to the wiper blade.

The present invention is concerned with the particular connection between one end of the link 11 with the belt 1, while permitting the latter to pass over the pulleys. As shown in FIGS. 1 and 2, the belt 1 has a series of transversely arranged longitudinally spaced projections or ribs 2 which are intended to enter a series of correspondingly spaced notches 3 in two spaced pulleys 4 one of the two pulleys being shown in FIGURES 3 and 4.

'As will be seen clearly in FIGURE 1 the belt 1 is formed with a tuck generally indicated by 5, the belt being bent about a transverse axis so that the two projections 2 adjacent the bend abut, the next two adjacent projections being spaced apart an amount 2a exactly double the normal spacing a. In this case when the tuck passes over a pulley one of the notches in the pulley lying beneath the belt will not be entered by a projection but this will not materially adversely afiect the drive between the pulley and belt.

The driving pad indicated generally by 6 takes the form of a bracket carrying three laterally projecting spaced pins 7 which are threaded at their extremities to receive securing nuts 8 which engage a loose link 9 drilled to receive the three pins.

The pins are so spaced that the belt is held firmly in the shape of a tuck, the belt being in addition gripped between the bracket and the loose link when the nuts are tightened.

The bracket 6 includes an olfset part 10 having an axial protuberance forming a bearing for a link 11 intended to move a carriage carrying a windscreen wiper arm, the link being located between part 10 and a disc like member 12, parts 10 and 12 being threaded or otherwise connected together.

The pins 7 may carry distance sleeves 13 or may be of increased diameter intermediate their ends to form shoulders against which the link will abut to limit pressure on the edges of the belt.

In the case of the modified arrangement shown in FIGURES 3 to 5, the driving pad 6 is of substantially rectangular shape in plan and of substantially arcuate a rectangular slot "or opening through which the tuck' in the belt is passed, a pin 14 having a length greater than the length of the slot being passed through the tuck and maintained in that position by two split pins 15 passing through diametral holes in the pin near its extremities. In this case the distance a separating the projections 2 on the belt immediately below the pad is the same as the distance a separating the remainder of the projections,.the arcuate formation of the pad enabling the latter to pass easily around the pulleys. The remainder of the pad corresponds substantially with the pad shown in FIGURES 1 and 2.

The pad 6 shown in FIGURE 6 has been designed primarily for use with fiat belts devoid of projections or ribs. The construction is very similar to that shown in FIGURES 1 and 2 except for the fact that the three pins 7 are arranged in the form of a triangle to fit closely around the belt. The pins may be screw threaded at their extremities to receive securing nuts engaging a separate link or plate whereby the belt will be gripped at its edges to connect it firmly to the pad, the belt passing freely over the pulley without interference.

The two outer pins support the belt against outward radial displacement and the central pin against inward radial displacement, the central pin being enclosed by the tuck.

It will be appreciated that in the case of the power grip type of belt, accurate registration of the projections or ribs with the notches in the pulleys will be maintained and due to the fact that in all cases the parts of the belt on the inside of the pad are free to move inwardly to conform to the periphery of each pulley, the belt will pass around pulleys of quite smaller diameter.

' We claim:

1. A wiper assembly comprising a pair of spaced sprockets, an endless ribbed belt passing around said sprockets, a bracket member having projecting means extending therefrom, a portion of said belt being gripped by said projecting means to fasten said belt to said bracket member, said belt being folded outwardly so that said portion thereof conforms to the curvature of said pulleys, a carriage for wiper blades, a link member hinged at one end to said carriage and at the other end to said bracket,

andmsans Q E Y'? an? 9 q u e t impart pr qa movement to said carriage.

2. The assembly of claim 1, wherein said projecting means is in the form of three laterally spaced pins, said pins being so positionedfthat one pin is enclosed by the foldjrin'the belt, the 'belt'being'of the flat type, the portions of the belt on opposite 'sides of the fold lying beneath'theremaining pins'and beingfree to move radially inwardly to adapt themselves-to the curvature of the pulleys.

3. The assembly of claim. .1, wherein said projecting means gis inthe form of three laterally projecting pins all lying in substantially the same plane, the fold in the belt enclosing the central pin, the portions of the belt on opposite sides of the fold passing between the central pin and the outer pins lying beneath the outer pins, the pins bein'g'so arranged and constituted thatthe ribs on the'belt lying .beneath said bracket are spaced apart an amount equal to double the normal spacing of the ribs to insure correct meshing of the ribs with said sprockets.

4. The assembly of claimt3, wherein the ribs on the belt lying within the 'fold abut face to face.

5. The assembly of claim 1, wherein said bracket is formed with a rectangular shaped slot through which the fold in the belt projects radially outward and wherein said projecting means is in the form of a pin having a length greater than thewidth 0f the belt and the width of the slot, the ends of the pin projecting beyond the longitudinal edges of the slot abutting the upper surface of the bracket adjacentthe edges of the slot, the ribs on the belt lying within the fold abutting face to face. 1

6. The assembly of claim 5, wherein .the fold is so constitutedthat the normal spacing of the ribs on the belt isunaffected, the portions of the belt lying beneath the" bracket being free to moveradially inwardly to conform to the curvature of said pulleys.

7. The assembly of claim 5, wherein said pin is bored radially at its extremities, and further comprising a pair of split cotter pins extending through the bores to hold the pin in position.

No references cited. CHARLES A. WILLMUTH, 'P rimary Examiner.

ROBERT I. SMITH, Assistant Examiner.

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