Patent GB-795126-A (GB)
Title: Improvements in and relating to windscreen cleaner systems
IPC: B60S1/48
Filed: 1956-06-27
Abstract: 795,126. Windscreen cleaners. GENERAL MOTORS CORPORATION. June 27, 1956 [July 11, 1955], No. 19885/56. Class 138(1). [Also in Group XXXII] A control mechanism 58, Fig. 1, for a windscreen wiper motor 36, and the motor of a windscreen washer pump 46, comprises a shaft 70, Fig. 3, which is movable axially and rotatably in a housing 60 and is adopted upon either axial or rotary movement to control the operation of one motor e.g. 36, and upon a predetermined axial movement to additionally control the other motor, e.g. the pump motor ; a spring 82 which biasses the shaft 70 in one direction of axial movement ; and a time delay mechanism 100, 106, 110, 112 and 114 (see also Fig. 4) connected to the shaft 70 so as to retard the movement of the shaft by the spring 82. The pump motor is actuated on its intake stroke, air which it takes in liquid from a reservoir 50, Fig. 1, by an electric solenoid connected by wires 52, 54 and contacts in the mechanism 58 with a battery 56, the delivery stroke of the pump being effected by a spring. The motor 36 may be operated by fluid pressure or an electric motor and is controlled from the mechanism 58 by a cable 88. Referring to Fig. 3, the shaft 70 has a manual operating knot 72 and a worm 80 secured thereto, the latter engaging a worm shaft 84 connected to the control wire 86 of the cable 88. An insulating sleeve 90 and electrical contact 92 are provided on the shaft 84 and when the shaft 70 is moved to its limit to the right the contact 92 engages a contact 94 and thus completes the pump motor circuit. If the knob 72 is merely rotated when in the position shown in Fig. 3, the worm shaft will move from an " OFF " position through " LOW " and " HIGH " speed positions for the wiper motor 36. However the pump motor will only operate when the shaft 70 is pushed fully to the right in which case the wiper motor will operate at high speed. Referring to Figs. 4 and 5, a rack 100 is connected to the shaft 70 by apertured legs 102, 104, which engage in grooves 74, 76 in the shaft, whereby the shaft 70 can rotate relative to the rack, but moves with the shaft 70 as the latter moves axially. A spring yoke 98 is connected between the rack 100 and another groove 78 in the shaft 70. The rack 100 co-operates with a ratchet wheel 106 rotatable in the housing 60. The ratchet wheel 106 has an integral flange 110 which cooperates with a fixed disc 112 with the interpositioning of a liquid silicone layer 114 the latter having a high viscosity. As the shaft 70 is moved to the right in Fig. 4, the wheel 106 remains stationary the rack being depressed against the spring yoke 98. However after the pump motor is energised and the knot 72 is released the pump motor spring effects the delivery stroke of the pump to delivery liquid to nozzles 38, 40 onto the windscreen, 10, Fig. 1. The rack 100 also engages and rotates the wheel 106 but the outward movement of the shaft 70 by the spring 82 is retarded by the layer 114 between the flange 110 and disc 112. Preferably the arrangement is such that the wiper motor will continue to operate slightly after the delivery stroke of the pump 46 is completed if the angular setting of the knot 72 corresponds initially with the " OFF " position of the wiper motor. However if the wiper motor was operating at a particular setting this setting will be retained after the pump ceases to operate.