Automatic servo drive for flap on vehicle

摘要

An automatic servo drive to open and close a flap on a vehicle, e.g. boot lid, comprises an electric motor (3) with a reduction gear and a pinion (6) mounted on a support plate and fitted to the inside of the vehicle. The pinion drives a rack (7) which slides over a fixed stop (8) set into a slot (9) running the length of the rack. The other end of the slot has a lug (10) fitted to a swan neck hinge (12) attached to the flap (2). The lug is linked to the end of the rack by a spring (16). The position of the lug is monitored by a sensor (17) to switch off the servo motor in the closed position and in the fully open position. The spring accommodates any motor overrun and thereby dispenses with the need for a clutch in the drive linkage.