Apparatus for controlling a vehicle window wiper system

• Main Authors: KADE, ALEXANDER, GRAHAM, DONALD ELLIS, KOWALIK, JAMES JOSEPH
• Format: Patent
• Language: English; French; German
• Published: 11.06.1986
• Edition: 4
• Subjects: PERFORMING OPERATIONS; SERVICING, CLEANING, REPAIRING, SUPPORTING, LIFTING, ORMANOEUVRING OF VEHICLES, NOT OTHERWISE PROVIDED FOR; TRANSPORTING; VEHICLES IN GENERAL

A control apparatus for separately driven, potentially interfering wiper blades (11, 14) includes position sensors (24, 25) for each wiper blade and a memory (23) which stores, for each pattern, numbers representing inner (26, 27) and outer (26' 27') wipe positions with acceleration, constant velocity and deceleration regions therebetween and a command velocity for the constant velocity regions. The memory further stores numbers defining a zone (29-27', 26-28) of potential blade interference and, for each position of each blade within this zone, a non-interference zone (27-29, 28-26') for the other blade. The control apparatus further includes closed loop velocity control apparatus (18. 21, 23) responsive to the signals from the position sensors and the command velocity to maintain the command velocity in the constant velocity region, accelerate to the command velocity in the acceleration region and decelerate from the command velocity in the deceleration region. The control apparatus also synchronizes the wiper blades at each of the inner and outer wipe positions and includes apparatus responsive to signals from the position sensors indicating that both of the blades are within the zone of potential blade interference to derive from the memory, for the position of the blade in advance in the direction of common blade movement, the non-interference zone for the other blade and prevent the other blade from leaving this zone.