Window wiper control for vehicle

Claim 1

A window wiper control for a motor vehicle having a window and a wiper mechanism including an electric motor effective, when activated, to drive a wiper across the window in repeating cycles of a wiper pattern with a pause in a park position between successive cycles, the window wiper control comprising, in combination: a source of electric power; a pulse switch; a park switch responsive to the wiper mechanism to close a first circuit path when the wiper is in its park position and alternatively close a second circuit path throughout the rest of the wipe pattern; a relay having an armature connected in series with the motor, source of electric power and pulse switch through a normally closed contact and further connected in series with the motor, the first circuit path of the park switch and source of electric power through a normally open contact, the relay further having an activating coil effective, when activated, to move the armature out of contact with the normally closed contact into contact with the normally open contact, the relay armature being further connected in series with the motor and the second circuit path of the park switch for dynamic braking of the motor when the relay armature is in contact with the normally open contact and the second circuit path of the park switch is closed; an electrically controlled switch connected in series with the relay coil and electric power source and having a control terminal; a capacitor connected in series with the park switch and electric power source so as to be charged to a high voltage when the park switch is closed, the capacitor being further connected to the control terminal of the electrically controlled switch so as to close the switch with the high voltage; a resistance comprising a discharge current path for the capacitor effective to slowly discharge the capacitor to a low voltage when the park switch is open, the low voltage being applied to the control terminal and effective thereby to open the electrically controlled switch, whereby closure of the pulse switch initiates an immediate cycle of the wipe pattern and a new such cycle after each pause through the normally closed contact of the relay with the remainder of each such cycle being activated through the normally open contact of the relay, the relay armature being held in contact with the normally open contact as the capacitor discharges with the park switch open to create the paused between successive cycles of the wipe pattern.