DRIVE UNIT FOR OVERHEAD DOORS

摘要

The invention relates to drive units for the motive movement of upwardly opening swing doors, such as, for example, garage doors. So that these drive units can be as little susceptible to faults as possible and nevertheless be small and lightweight, it is proposed to accommodate the limit switches (8) protectively within the drive housing consisting of the base plate (1) and cover (2). Since the output shaft (5) projects outwards through the base plate (1), where a pinion (7) for driving a chain (18), for example, is fastened to it, it is proposed to push a bush (12), especially consisting of plastic, fixedly in terms of rotation onto an outside diameter of the pinion (7), in such a way that the bush (12) projects back just inside the housing coaxially relative to the output shaft (5), this end of the bush (12) having a bevel gear (13). There meshes with this a bevel pinion (14) at the end of a threaded rod (9) on which are located nuts (10) which are prevented from corotating with the threaded rod (9) by an angle piece (16) bearing in parallel against them and which consequently move axially along the threaded rod (9) in a similar way to the movement of the door. Because the limit switches (8) are arranged parallel to the threaded rod (9), these nuts (10) of variable basic position as a result of the removal of the angle piece (16) are used for actuating the limit switches (8).