IMPROVEMENTS IN WIPER BLADES

Abstract: Combination of a connector, which is an elongate element having parallel side faces (24) and penetrated by a bore (23) perpendicular to the side faces, and a pivot pin (33), which is received in the bore (23) and protrudes from both ends thereof, the pivot pin being retained in the bore by means of a resiliently supported projection (26, 45) extending either radially into the bore (23) or radially outwardly from the pin (33), the resilient projection (26, 45) engaging the side walls of either a groove (34) formed in a pin (33), or of a recess (43) formed in the connector and communicating with the bore (23). The connector is pivotally mounted in an elongate opening (36) in a wiper blade harness, the side walls (37) of the opening being formed with holes (38) into which the ends of the pin (33) project, and is adapted to engage and retain the end of a windscreen wiper arm.

Description: TRICO-FOLBERTH LIMITED Improvements in Wiper Blades This invention relates to wiper blades for vehicles and more particularly to connecting' a wiper arm to a wiper blade by an intervening connector which can be mounted pivotally between opposite parallel side walls of an opening between the ends of the wiper blade. Various prior proposals have been made, for example in U.K. patent specifications Nos.. 1 295 592 and 1 376 878 which disclose a bearing pin forming part of a wiper blade, and a connector for retaining an end portion of a wiper arm, the connector being, respectively, detachably and permanently mounted for pivoting on the bearing pin. When the bearing pin is of metal, a forming- opera¬ tion is usually required to retain the pin. The operation entails forming a head at one or both ends of the pin in the manner of rivetting. As this forming operation is usually carried out on a completed wiper blade harness which, if of metal, means after paint cr other finish has been applied to the harness, the head on the pin needs to be painted or otherwise finished for the sake of weather-proofing or appearance, and the paint or finish on the harness around the head on the pin needs to be inspected, and restored or treated if damaged by- the head forming operation. An object of the present invention is to eliminate the head forming operation on the pin and thereby the above disadvantages which may attend the operation. The invention is, however, not limited to the use of a harness and a pin which are of metal: the harness or pin or both may be of plastics. The present invention resides in the combination of a connector and a bearing pin for use therewith for pivotally connecting a wiper arm to a wiper blade which has between its ends an opening with opposite parallel side walls, for receiving the connector and the arm for pivotal movement, the connector being elongate and having a pair of opposite parallel external side faces, a portion for supporting an end portion of the wiper arm longitudinally of the connector and on which portion of the connector there is provision for retaining the end portion of the wiper arm, and a transverse bore extending at right angles to the side faces for receiving the pin, the pin being longer than the distance between the side faces, characterised, in that the pin is separate from the connector and is re ainable in the bore by cooperation between abutment surfaces on the connector and the pin, the abutment surfaces co ing into interlocking relationship with a snap action, and the ends of the pin, when the pin is so retained in the bore, protruding from the side faces of the connector for pivotal engagement in corresponding holes in the side walls of the wiper blade opening. Examples embodying the present invention are illustrated in the accompanying drawings, in which: Figures 1 to 3 are a longitudinal section, an underside plan and an end view, respectively, of a first connector, and Figure 4 is a plan of a bearing pin for use with the first connector; Figures 5 to 7 are views of a second connector in side elevation, underside plan and end view, respectively, OMPI ,. VV//IIPPOO and Figure 8 is a plan of a bearing pin for use with the second connector; Figure 9 is an underside plan of a third connector, and Figure 10 is a side view of a bearing pin for use with the third connector; and Figure 11 is a longitudinal section of the third connector and its bearing pin in assembled condition. Similar reference numerals are applied to corresponding parts in the drawings of the connectors and bearing pins. Referring to the drawings, the connector 10 shown in Figures 1 and 2 is an elongate plastics moulding of substantially K-section as viewed in Figure 3 > comprising equal opposite parallel side plates 11 united by a web 12 to provide a groove 13 corresponding in form, width and depth to a U-shape hook termination of a wiper arm 15 of rectangular cross-section, shown in chain line in Figure 1. Upper and lower parallel portions 16 , 17 of the hook lie longitudinally of the connector 10 for support in corresponding portions of groove 13 of the connector when in assembled condition, and a semi-circular curved portion 18 of the hook .lies in a corresponding arcuate portion 19 of the groove 13. The web 12, as seen in Figure 1, comprises an upper straight portion 20 which extends from the left hand end of the connector 10 and parallel to the longitudinal edges of the side plates 11; an intermediate portion 21, and a lower straight portion 22 parallel to the upper portion 20. The intermediate portion 21 of the web has a cylindrical bore 23 which extends transversely of the connector at right angles to its opposite external side faces 24 which are parallel.. To the right of the"bore 23 as seen in Figure 1, part of the base of the arcuate groove portion 19 is semi-cylindrical and substantially - L coaxial with the bore 23 , but the surface is flat or otherwise relieved at 19a. above and below that part of the base . To the left of the b ore 23 3 the web portion 21 includes a rounded proj ection 2β which protrudes into the bore 23 at mid- length , towards the bore axis . Opposite sides of the proj ection 2β constitute abutment surfaces 126 as later des cribed. The proje ction 26 is integral with a bar- like element 27 formed parallel to the bore 23 during moulding of the connector , using a core which forms two slots 28 above and belovr the element 27 , thereby demarcating it from adj oining parts of web portion 21. The element 27 provides resilient support to the proj ection 26. The lower portion 22 of the web divides into two side parts 22a to the left of the intermediate portion 21, and between these two parts 22a. there extends a straight tongue 29 which inclines, outwards away from the upper portion 20 of the web . The tongue carries a detent 30 with an abutment surface 30a and has a free end 29a beyond the left hand ends of the side plates 11. The tongue is resilient in a plane parallel to the side plates 11 , so that the detent 30 can be engaged in an opening 32 in the lower portion 17 of the wiper arm hook and can cat ch the wall or abutment surface 32a of an opening 32 in the wiper arm as hereinafter des cribed. The bearing pin 33 s Figure 4 , may be of plastics or of metal , and is sub stantially cylindrical and of slightly less diameter than the bore 23 into which it is received when assembled with the connector 10 . At mid-length the pin 33 is formed with a circumferential groove 34 of U cross-section" hich can receive the proj ection 26 with slight clearance in the axial sense of th-e pin , ' Opposit.e sides of the groove 3 constitute abutment surfaces 134 for cooperation with abutment surfaces 126 on the pin as later des cribed . OMPI The connector 10 is used in conjunction with the pin 33 to establish- a pivotal connection between the wiper arm 15 and a wiper blade 35. A fragment of the harness portion of the wiper blade is shown in chain line in Figures 1 and 2. The connector is assembled in an opening 36 defined by stiff, parallel side walls 37 of the wiper blade 35. The spacing of the side walls 37 is slightly greater than the width of the connector between its external side faces 24, so that the connector can pivot freely in the opening 36. The bore 23 of the connector is aligned with corresponding holes 38 in the side walls 37 of the wiper blade. During assembly procedure the bearing pin 33 is first aligned with the holes 38 and bore 23 and pushed into them by hand, the pin 33 having a running fit in the holes 38 and a sliding fit in the bore 23. The leading end of the pin encounters the projection 26., and pushes it back in opposition to resilient force exerted by the element 27. The projection 26 snaps into the groove 34 in the pin 33 when the pin reaches its working position in the assembly, and the pin is thereby retained by cooperation between the abutment surfaces 126, 134 which come into interlocking relationship with a snap action. The ends of the pin, when the pin is so retained in the bore, protrude from the side faces 24 of the connector and engage in the holes 38 in the wiper blade for pivoting. The end of the wiper arm 15 can be hooked onto the connector 10 either before or after mounting the connector on the wiper blade 35. In either case, the hook end of the wiper arm is drawn on to the connector so that the straight portions 16, 17 of the hook lie along the straight portions of the groove 13 of the connector. The arm and connector become fully assembled when -the curved portion 18 of the hook engages the arcuate portion 19 of the web. Just before the arm engages the portion 19, the detent 30, urged by the resilient tongue 29, snaps into the opening 32 in the arm. The arm is secured against further longitudinal movement in relation to the connector, on the one hand by engagement of the arcuate portion 19 and the curved portion 18, and on the o.ther hand by abutment surface 30a on detent 30 catching the surface 32a of the wiper arm opening 32. The connector 10 thus establishes pivotal connection between the wiper arm 15 and the wiper blade 35. The wiper arm can be released by deflecting the free end 29a of the tongue 29 upwards (Figure 1) by hand to lift the detent 30 clear of the opening 32, and then sliding the wiper arm to the right until the hook is clear of the connector and can be withdrawn from the wiper blade opening 36. Once the wiper arm has been- disconnected, the connector can, if desired, be disassembled from ' , the wiper blade by forcing the bearing pin 33 out of the holes 8 and the bore 23, and. then withdrawing the connector from the wiper blade opening 36. The second connector, shown in Figures 5 to 7, differs from the first connector in the form and location of the element and projection used, and the bearing pin, Figure 8, for use with the second connector is shaped accordingly. An element 2 ' 7a of the second connector extends as a cantilever parallel to the axis of bore 23 to one end of the bore, from inside a recess 135 in the outer face of one of the side walls of the connector and open to the bore 23. The free end Of the cantilever element 27a. is formed with a lateral projection 26a which normally protrudes into the bore 23 towards its axis. The projection 26a has a cylindrically concave face coaxial with the bore 23, and has radial opposite sides or abutment surfaces 126a. O PI The other features of the second connector correspond with those of the first connector, as indicated by the corresponding reference numerals. The bearing pin 33, Figure 8, is formed with a circumferential groove 34a adjacent to one end for reception of the projection 26a. The sides or abutment surfaces 134a of the groove 34a are preferably radial. Application and assembly procedure of the second connector and bearing pin correspond with those of the first connector and bearing pin. Either form of connector illustrated may be moulded to provide a socket or passage for reception and retention of a straight-ended wiper arm, at right angles to the bore 23. Figures 9 and 11 show a third connector 10a moulded for reception of a straight-ended wiper arm of rectangular cross-section. Figure 11 shows .in chain line the arm 15a. assembled with the connector. Figure 10 shows a bearing pin 33b. for use with this connector 10_a,but it is to be understood that bearing pin 33b can be used with either of the first two connectors if they are moulded to provide appropriate abutment surfaces, which are described hereinafter with reference to Figures 9 and 11. The connector 10a. is an elongate moulding having a pair of opposite parallel external side faces 24a. (Figure 9) and a longitudinally extending socket 39. The entrance to the socket has, as its underside, the customary resilient tongue 42, the free £nd 4 ' 2a of which can be manipulated to deflect It downwards from its position in Figure 11 to- assist insertion of the arm 15a and principally the forcing of a stop 40 formed on the arm through the entrance of the socket to locate - it in -a ho-le 4l; alternatively, to assist withdrawal of the arm from the socket. A bore 23a for reception of the bearing pin 33b. extends transversely of the connector Oa., at right angles to the side faces 2 ' 4_a. The bore 2 " 3.a is intersected at right angles by the opposite sides or abutment faces 143 of a recess 43 which extends away from the bore between its outer ends. The bearing pin 33b. (:Figure 10) is of substantially cylindrical form, corresponding in diameter 30 to the bore 23a in which it " has a sliding fit, with the exception of resilien ly supported projections 45 protruding from the circumferential surface of the pin 33b.. Two such projections 45, arranged diametrically opposite each other, are shown present in Figures 10 and 11, but a single such projection is adequate. Each projection 45 is formed on a segmental supporting portion 33 of the pin, produced by dividing the pin longitudinally with a slot 47 between the ends of the pin; and the projection can have the rib form shown, extending circumferentially and having radial sides 145 joined by a rounded crest. Each supporting portion 33.C has resilience radially of the pin to afford the corresponding projection resilient support. The connector 10a, either before or after being assembled with the wiper arm 15a, is assembled in an opening corresponding to opening 36 in the wiper blade shown in Figures 1 and 2. The side faces 24a of the connector ICa have just sufficient clearance between the opposite sides of the blade opening to permit free pivoting. The connector 10a is supported for pivoting in bearing holes in the opposite sides of the blade by insertion of the pin 3_ by hand. Projections 45, on encountering the sides of the bearing hole into which the pin 33b. is being inserted, and of the bore 23_a, are forced radially inwards against the resilience of - - the supporting portions 33 of the pin, the slot 47 being of width adequate to allow the p.in portions 33 to flex inwards simultaneously and to permit the projections 5 to enter the bearing hole in the blade and the bore 2 ' 3a in the connector. The projections 4 snap radially outwards inside the recess 43 under the resilience of their supporting portions 33 . The opposite sides 14 3 143 of the projections and of the recess, respectively, coopera ' te as abutment surfaces in interlocking relationship and retain the pin "33b with its ends protruding from the side faces 24a of the connector as indicated in chain line in Figure 9 S to engage in the bearing holes in the wiper blade for pivoting.

Claims: AMENDED CLAIMS (received by the International Bureau on 1st July 1980 (01.07.80)) 1. The combination of a connector and a bearing pin for use therewith for pivotally connecting a wiper arm to a wiper blade which has between its ends an opening, with opposite parallel side walls, for receiving the connector for pivotal movement, the connector being elongate and having a pair of opposite parallel external side faces, a portion for supporting an end portion of the wiper arm longitudinally of t-he connector and on which portion of the connector there is provision for retaining the end portion of the wiper arm, and a transverse bore extending at right angles to the side faσes for receiving the pin, the pin being longer than the distance between the side faces, characterised in that the pin (33) is separate both from the connector (10) and from the wiper arm (15) and, when the connector is in operative position within the opening (36), can be inserted into an operative position in which a central part of the pin lies in the bore (23) of the connector while end parts of the pin lie in respect¬ ive holes (38) in the side walls (37) of the wiper blade, the insertion requiring solely the application of axial force to the pin relative to the arm and connector, the pin being located and restrained in the operative position by cooperation of abutment surfaces (e.g. 134, 126 Figures 1 to 4) on the pin (33) and connector (10), at least one of these abutment surfaces being resilient radiall OMPI_ (126) whereby the abutment means automatically snap Into interengagement when the pin reaches operative position. 2. A combination according to claim 1, characterised in that the abutment surfaces (134, 126) are in part provided by a projection (26) resiliently supported on the connector (10) to protrude towards the axis of the bore (23), and in part provided by a circumferential groove " (34) in the pin for receiving the projection and thereby reta-inirig the pin in the bore. 3. A combination according to claim 1, characterised in that the abutment surfaces (143, 145, Figures 9 to 11) are in part provided by opposite sides of a recess (43) in the connector, the recess extending from the bore (23a.), and in part by a resiliently supported projection (45) protruding from the circumfer¬ ential surface of the pin (33b.). 4. A combination according to claim 3, characterised in that the projection (45) is formed on a segmental portion (33 ) of the pin produced by dividing the pin (33b) longitudinally with a slot (47) between the ends of the pin, the segmental- portion having resilience radially of the pin to afford the projection resilient support. 5. A combination according to claim 1 or claim 2, in which the abutment surfaces (126) on the pin (33) are at the mid-length of the pin. OMPI STATEMENTUNDERARTICLE19 The preamble to amended claim 1 differs only slightly from the preamble as first filed. This preamble is based on British Patent Specification 1 376 878 (mentioned at page 1 line 8 of the application) which is a more appropriate starting point for the invention than French 2 133 340 listed in the International Search Report. Reference to the arm at original claim 1 line 5 has been omitted, because in the construction shown in Figures 9 to 11 the arm does not enter the opening in the wiper blade. The characteristic part of claim !• has been extensively rewritten in order to define the invention more precisely. The amended claims contain an additional claim 5, directed to a feature described at page 4 lines 29 to 31 of the application. OMPI

Inventors: MOWER P
Applicants: TRICO FOLBERTH LTD
Application year: 1980
Main classification: B60S1
IPC codes: B60S1