Windshield wiper control system responsive to vehicle speed

Claim 1

In a vehicle windshield wiper control system having an electrically driven wiper motor having a speed input, an operator control switch coupled to the motor and having a delay position wherein the motor operates intermittently, a vehicle speed sensor, and a control unit coupled to the control switch, the motor, and to the speed sensor, a method of controlling operation of the motor, comprising the following steps: (1) checking the status of the operator control switch; and (a) if the operator control switch is not in its delay position, resetting a dwell timer/counter to an initial value and deactivating the wiper motor; else (b) if the operator control switch is in its delay position, incrementing the value of the dwell timer/counter; (2) checking the value of the dwell timer/counter; and (a) if the value of the dwell timer/counter is less than a minimum value, energizing the wiper motor; else (b) if the value of the dwell timer/counter is greater than said minimum value, computing, as a function of the vehicle velocity, a delay time value representing a desired delay time between operations of the motor; (3) comparing the value of the dwell timer/counter to the delay time value; and (a) if the value of the dwell timer/counter is greater than said delay time value, resetting the dwell timer/counter to its initial value and deenergizing the wiper motor; else (b) if the value of the dwell timer/counter is greater than said delay time value, deenergizng the wiper motor; and (4) periodically repeating steps (1)-(3).