GB1244496A - Windshield wiper system for automative vehicles - Google Patents

Abstract

1,244,496. Windscreen wipers. McCORD CORP. Oct.28, 1968, No. 51108/68. Heading A4F. [Also in Division H2] In a windscreen wiper system in which a wiper is driven intermittently by an electric motor a housing 34 rotatably supports the wiper spindle 25 on which are rotatably mounted cams 41, 42 selectively engageable with the actuating member 73 of a switch 32 to open and close the wiper motor circuit, and a lost motion device connects the driving mechanism coupling the motor with the spindle 25, the cams 41, 42 being disengaged from the actuating member 73 for a predetermined time period during which a member 47 of a time delay device is spring actuated to rotate the cam 41 to close the switch 32 at the end of the time period, when the wiper motor is energized to rotate the cams 41, 42 and move the member 47 in the opposite direction. The time delay device 31 is pneumatically controlled and the member 47 is a rod connected to a piston 49 Fig.3 (not shown) movable in a housing 56 to which air is admitted via a bleed tube 55 which is pinched to control the air flow therethrough. The circuit for controlling the wiper motor 18, Fig. 5, and a motor 117 driving a windscreen washer pump, comprises a manually controlled multiple switch 30 including switches 94, 96, 97 having rotatable switch arms 94a, 96a, 97a, and 98a respectively, simultaneously movable to three positions for (a) wiper parking (b) continuous or intermittent wiping operation, and (c) windscreen washer operation with continuous or intermittent wiping operation. When the switches 94, 96, and 97 are in their wiper parking positions the circuit through said switches and the motor 18 is opened at the parking switch 113. When the switches 94, 96 and 97 are moved to their wiper operating positions as shown in Fig. 5 the circuits of motor field coils 105, 107 are completed via switches 101, 102, respectively. With the switch arms 101a, 102a maintained in engagement with the resistance 101c and bridge terminal 102b respectively, the wiper motor 18 will run continuously at a speed controlled by the setting of the arm 101a and the resistance 101c. To operate the wiper motor 18 intermittently the switch arm 102a is set to engage terminal 102c so that the circuit through the field coil 107 is completed through the switch 32 controlled by relative rotation of the cams 41, 42. To operate the washer pump during either intermittent or continuous wiper operation the switch members 94a, 96a 97a, and 98a are moved to the dotted line positions shown in Fig. 5 to operate the motor 117 without affecting the wiper operation.