Control system for operating a window wiper in response to water moisture

摘要

An automatic control system for operating an electrically actuated device, such as a windshield wiper, power window, sun roof or convertible top of a motor vehicle, in response to the presence of water moisture. The control system includes a moisture sensor having a plurality of spaced apart, exposed conductive strips, the strips being arranged in adjacent pairs; a voltage source coupled to one strip of each pair; a current detector coupled to the other strip of each pair to discriminate between the presence or absence of moisture droplets on each pair; a drop accumulation detector, coupled to the current detector, for determining the number of pairs of sensor strips which are contacted by moisture droplets; and an electrical switch, coupled to the droplet detector, for switching on the electrical device in response to the number of droplets present on the moisture sensor.