Patent GB-790283-A (GB)
Title: Improvements in or relating to windshield wipers
IPC: B60S1/34
Filed: 1954-10-12
Abstract: 790,283. Windscreen cleaners. PRODUCTIVE INVENTIONS, Inc. Oct. 12, 1954 [March 26, 1954], No. 29358/54. Class 138(1). A windscreen wiper arm assembly comprises an inner section 1, Fig. 1, securable on a drive shaft 6, an intermediate section 2 pivoted to the section 1 and an outer extensible section 3 carried by the section 2, a connector 30 pivoted on the outer end of the section 3 for supporting a blade, an actuator 23 movably supported on the arm assembly, means 20, 25, operatively connecting the connector 30 with the actuator 23, and means 15, 18 for'operating the actuator 23 to pivot the connector 30 after the extensible section 3 has moved a predetermined extent relative to the intermediate section 2. The inner section 1 of the wiper arm is secured to the wiper shaft 6 in any desired angular position by means of clutch members 4 and a nut 5. Also secured to the shaft mounting 7 by means of nuts 40, 41 is a fitting 39, Fig. 7, provided on its under surface with serrations which coact with serrations 45 on the nut 40, whereby the angular position of the fitting relative to the mounting may be adjusted. The intermediate section 2 of the wiper arm is provided with a chamber 8 to house, an arm spring 9 secured between a clutch member 4 and a cross-pin 10, and the abutment member in the form of a U-shaped spring the legs 15 of which have off-set ends 16 to engage as desired in any one pair of three pairs of holes 17 in the section 2. The section 2 is also formed with a recess 11, a groove 12, and an elongated shoulder 13 which constitutes an extension of the groove 12. Slidably mounted in the groove 12 and against the shoulder 13 is the rectangular-section extensible section 3 of the wiper arm which at its outer end pivotally carries the connector 30 for the wiper blade. At its inner end the section 3 is provided with an opening 2, Fig. 2, and a narrower opening 22 which joins a groove 19. A lub 14 at the inner end of the section 3 is pivotally connected to one end of a secondary arm 37 the other end of which is pivoted to a link 38 which in turn is pivoted by a bolt 43, Fig. 7, to the fitting 39. Mounted on a pin 24 in the opening 21 is the actuator 23 which is pivotally connected by a pin 28 with a link 25, mounted in the opening 22 and pivoted at 26 to a rod 20 slidable in the groove 19. This rod is bent at its outer end and provided with an upturned offset 33 which engages in a slot 32 in a link 31 secured to the connector 30, Fig. 2. The section 3 and rod 20 are retained in place in the section 2 by means of a cover 34 secured to the section 2 by a cross-pin 35, Fig. 1. As shown in Fig. 2, the inner end of the cover 34 and the side wall of the section 2 are cut away to allow passage of the lug 14, and the inner end 36, Fig. 3, of the base wall of the cover is spaced from the bridge portion 18 connecting the legs 15 of the abutment member. When the arm is oscillated by the shaft 6 the secondary arm 37 causes the section 3 and the rod 19 to move together inwardly towards the shaft and as will be seen from Fig. 3, pivotal movement of the actuator 23 is prevented until the actuator passes inwardly beyond the end 36 of the cover 34. On passing beyond the end 36, a notch 29 on the actuator finally engages the bridge 18 of the abutment and further inward movement of the section 3 causes the actuator to be pivoted as shown in dotted lines in Fig. 3 whereby the rod 20 will be moved inwardly relative to the section 3 and thus cause the connector 30 and the wiper blade to pivot on the end of the wiper arm. When the wiper arm is applied to a curved windscreen having a frontal portion connected to a rearwardly extending wing portion, the wiper blade is moved bodily along the arm towards the wiper shaft as the arm moves towards the junction of the frontal and wing portions and as it passes the junction the blade is caused to pivot relative to the arm and thus ensure that it maintains contact with the wing portion. Without the provision of the final pivotal movement of the blade the outer portion thereof would not remain in contact the wing portion, as described with reference to Fig. 15 (not shown). Specification 790,284 is referred to.