Patent GB-902605-A (GB)
Title: Improvements in windscreen cleaners
Inventor: OISHEI JOHN ROFFO
IPC: B60S1/48
Filed: 1959-01-21
Abstract: 902,605. Windscreen cleaning systems. TRICO PRODUCTS CORPORATION. Jan. 21, 1959, No. 2276/59. Class 138 (1). A windscreen cleaning system comprises means for controlling the operation of both an electric wiper motor and a washer delivering a predetermined quantity of washing liquid at each operation, and a timing mechanism providing a period of conjoint operation of the wiper motor and the washer. The washer 5, Fig. 1, is operated when an electromagnetic valve 9 is actuated to place the washer in communication with the engine intake manifold 3, so that a predetermined quantity of liquid is drawn from a reservoir and discharged through nozzles 7 on to the windscreen. The wiper arms 11 are driven by an electric motor 12 via crankarms 13, 13<SP>1</SP>, Fig. 5, and connecting-rods 14. A worm 16 coupled to the motor-shaft drives pinions 17, 18, to which the crank-arms 13, 13<SP>1</SP> are secured, and having gear teeth in the ratio 4: 5 so that the wiper arms are in phase at one instant only during each five rotations of the pinion 17. The pinions 17, 18 are mounted in the casing 22 of a multiple switch comprising a contact 24, Fig. 6, connected to a resilient steel strip 25 adapted to be engaged with contacts 26, 27 by cam followers 17<SP>11</SP>, 18<SP>11</SP>, respectively, actuated by cams 17<SP>1</SP>, 18<SP>1</SP> integral with the pinions 17, 18. To start the wiper motor 12 the insulating disc member 32 of a rotary switch 30, Fig. 9, is rotated so that conducting bridges 37, 38 connect together leads 33, 34 and leads 35, 36, respectively, of the motor circuit and terminating at contact points in an insulating disc 31. To stop the wiper motor the disc 32 is rotated through 90 degrees so that the motor circuit is completed through either the contacts 24, 26 or the contacts 24, 27, or through both these pairs of contacts, and the motor 12 continues to run until the cams 17<SP>1</SP>, 18<SP>1</SP> are in positions such that the strip 25 is disengaged from both contacts 26 and 27, which occurs when the wiper arms are both in the parked position. To utilize the washer a switch 42 is closed momentarily to activate the electromagnetic valve 9. If the wipers are in use the closing of the switch 42 will not affect their operation, but if they are not in use the switch 42 completes momentarily a circuit through the motor 12 to energize it for a period determined by timing mechanism. The latter comprises a pawl (not shown) on the crank arm 13 which rotates a timing gear 48 one tooth at each rotation of the arm. As the gear 48 rotates, a split collar 49 secured thereto engages and rotates a lever 50 to hold the strip 25 engaged with the contact 26. A circuit through the motor 12 is thus maintained until the trailing edge of the split collar 49 has disengaged from the lever 50 and its other edge abuts against the latter, when the cams 17<SP>1</SP>, 18<SP>1</SP> are so disposed that the wiper arms are both in the parked position, the strip 25 being then disengaged from both contacts 26 and 27. Specifications 733,550 and 752,941 are referred to.