GB781885A - Improvements in or relating to windshield wiper assemblies and method of wiping a curved windshield - Google Patents

Abstract

781,885. Windscreen cleaners. PRODUCTIVE INVENTIONS, Inc. Dec. 20,1954 [May 7, 1954], No. 36731/54. Class 138(1). A method of wiping a rearwardly curved wing portion of a windshield by a wiper blade carried by a wiper arm, consists in oscillating the wiper arm across the windshield, reciprocating the wiper blade with respect to the wiper arm during the oscillation and rotating the wiper blade with respect to the wiper arm to cause the wiper blade to conform to the curvature of the windshield at all times. Referring to Figs. 1 and 2, the wiper arm comprises an inner section 1, adjustably secured by a nut 4 to a drive shaft 5 disposed in a mounting 6, an intermediate section 2 pivoted under the urge of a spring 7 to the inner section 1, a tubular guide member 8 secured in either of two positions to the section 2 by a rivet 9, and an extensible section 3 slidable and rotatable in the guide 8, which section 3 carries the wiper blade connector. A pin 13 Fig. 4, secured to the section 3, engages in a slot in the guide 8, the slot having a longitudinal portion 10 and a helical portion 11. The head 14 of the pin 13 is universally pivoted to one end of a secondary arm 15 formed of two members 16 riveted together as at 20. The other end of the arm 15 is universally pivoted to the head 17 of the shaft of a bolt assembly 18, Fig. 3, which is adjustably secured in a slot 27, Fig. 2, in a fitting 19 adjustably secured to the mounting 6 by nuts 25, 26, Fig. 1. The underside of the fitting 19 is serrated to engage serrations on the top of the nut 26. Referring to Fig. 9, as the wiper arm moves from the parked position shown in full lines, to the position 32, the pin 13 is caused to move along the slot 10 to thus slide the section 3 and wiper blade longitudinally of the guide 8 but without rotation relative thereto. As the wiper moves from position 32 to the position shown on the extreme right of Fig. 9, i.e. on the rearwardly extending wing 31 of the windshield, the pin 13 enters the slot portion 11 and the section 3 and wiper blade are thus rotated relative to the longitudinal axis of the guide 8, and the blade is retained in contact with and normal to the wing 31. Without the present construction the blade would follow the path 33 and on reaching the wing portion a part of the blade would be out of contact with the windshield and also the windshield frame would be fouled. In a modification described with reference to Fig. 2a (not shown) the slot in the guide is formed with two longitudinal portions with an intervening helical section. The adjustment of the fitting 19 relative to the mounting 6, the adjustment of the bolt assembly 18 on the fitting 19, and the adjustment of the guide 8 on the arm section 2, allow of the wiper assembly being used on different windshields.