Patent GB-762853-A (GB)
Title: Improvements in or relating to windscreen wiper apparatus
IPC: B60S1/12
Filed: 1952-11-10
Abstract: 762,853. Windscreen cleaners. O'SHEI, W. E. Nov. 6, 1953 [Nov. 10, 1952], No. 28264/52. Class 138(1). [Also in Group XXVI] A suction motor assembly for windscreen wiper apparatus comprises a double-acting suction motor in which a piston moves in a chamber to rock a shaft projecting from a bearing in the motor a bushing, means carried by the motor to support the bushing in alignment with the bearing and spaced away from the motor housing, the shaft or an extension thereof extending through the bushing, means for securing the bushing in an aperture in a vehicle body and two openings elading to the outside of the motor housing and respectively connected directly to the chamber at opposite sides of the piston. By the invention a main motor having the usual automatic and manual control valves can control the operation of ancillary suction motors. Referring to Fig. 1, the main suction motor 1 includes a housing 2 of arcuate shape in which oscillates a piston on a rocker shaft 3, an automatic change - over valve 5 and a manually controlled slide valve 7 operable by an arm 8. Fig. 2, pivotal on a connector 9 through which suction is applied to the motor. The arm 8 is movable by a Bowden cable and has a slot 10 engaging the end 11 of a lever 12 interconnected with the valve 7 and pivoted to the motor housing at 13. The construction and mode of operation of the motor is similar to that described in Specification 546,483 [Group XXVI], which is referred to. The motor chamber on each side of the piston communicates with tubular connectors 25, 26 which are closed by plugs 30 if the motor 1 is alone to be operated. The shaft 3, Fig. 4, extends through a bearing in the motor housing and a bush 18 carried by a bridge 16 secured to the housing by screws 15 and spacers 17. As will be seen 'in Fig. 2, the bush is received in an apertuer in the vehicle body 19 and is secured thereto by a spacer 21a passing over the bush and a nut 21, screwed on to the bush. The outer end of the shaft 3 is provided with means 20 for securing thereto a wiper arm. Between the bush 18 and the bearing in the motor housing the shaft 3 is made of hexagonal cross-section to receive a correspondingly apertured two part lever 23, Fig. 3. A groove 4 is provided on the shaft to receive a locating part on the lever 23. When it is desired to utilize a second wiper for the windscreen a motor 101 of similar construction to the motor 1, but without the provision of an automatic change-over valve and manual control valve, is secured, in the manner previously described, to the vehicle body The plugs 30 are then removed from the connectors 25, 26 and these are then connected in parallel with the parts of the motor housing 102 on opposite sides of its paddle by flexible tubes 27, 28 and connectors 125, 126. Control of the suction to opposite sides of the piston of the motor 101 will then be effected by the valves 5, 7 of the main motor 1. In order to ensure that the wipers on the two motor shafts 3, 103, will operate in unison the lever 23 on the shaft 3 is connected by a link 29 to a lever 123 on the shaft 103 of the motor 101. In a modification, Fig. 6 (not shown), the motor shaft itself does not extend through the bush. The end of a wiper spindle passing through the bush and the end of the motor shaft are then provided with square ends which engage in corresponding apertures in the opposite sides of the lever 23. The main motor may control more than one ancillary motor. The motor shafts between the bearings and bushes may be interconnected by pulleys and a chain, or the levers on the shafts may be interconnected by a flexible cable. According to the Provisional Specification the motor shaft may extend from the motor housing in both directions, one end passing through the bushing for connection with a wiper arm whilst the opposite end is secured to the lever or pulley for interconnecting dual wipers. Specification 383,877 also is referred to.