In a device for controlling a windshield wiper, in particular on a motor vehicle, the windshield wiper is switched on when a sensor indicates wetness above a preset threshold value. The windshield wiper can furthermore be turned on by a manually actuatable switch. The threshold value is reduced upon...http://www.google.com.au/patents/US5157312?utm_source=gb-gplus-sharePatent US5157312 - Device including wetness sensor for controlling a windshield wiper
