CONTROL FUNCTION-POWER OPERATED LIFT GATE
 Inventors: David J. Kowall, Hartland; Delbert D.
DeRees, Romeo; Thomas S. Moore,
Northville; David R. Bernier,
WhiteLake, all of Mich.
 Assignee: Chrysler Corporation, Highland Park, Mich.
 Appl. No.: 383,640
 Filed: Feb. 6, 1995
 Int. CI.6 H02P5/00
 U.S. CI 318/283; 318/266; 318/466;
 Field of Search 318/280-286,
318/255-256, 264-268, 445-446, 466-470; 49/26, 139-140, 279-280, 501-502
 References Cited
U.S. PATENT DOCUMENTS
4,533,901 8/1985 Lederie 340/52
4,634,945 1/1987 Takemura et al 318/469
5,155,937 10/1992 Yamagishi et al 49/280
FOREIGN PATENT DOCUMENTS
1314620 12/1989 Japan B60J 5/10
A lift type tailgate on a passenger van type vehicle body is operated by an electric motor powered actuator with an electronic control circuit utilizing a microprocessor operating under program control to respond to user-initiated opening and closing signals to move the tailgate in the selected direction. In the control circuit, feedback information to the microprocessor indicative of tailgate position is provided by a potentiometer coupled with the actuator motor and the microprocessor is programmed to operate with this information to stop the tailgate at a wide open position, a partially closed position and a fully closed position. Obstruction detection is performed by the microprocessor using an obstruction detection circuit and additionally by monitoring the position signal input from the potentiometer to stop the tailgate on encountering an obstacle. Activation of a tailgate latching mechanism is performed under the control of the microprocessor using a solenoid drive circuit and warning or alerting sounds indicating tailgate closure operation including tailgate stoppage at the partially closed position are provided in accordance with audio data received from the microprocessor.