A LINEAR BALLSCREW ACTUATOR WITH A SAFETY UNLOCKING DEVICE

摘要

The actuator controls the axial translation of a controlled output member (3) in response to axial movements of an input control member (1). A ballscrew mechanism (8.) has a rotatable nut (7) and an axially translatable screw (9) for coupling to the output member (3). An unlocking device includes a rod (20) secured to the control member (1) and locking balls (18) interposed between the rod (20), the controlled member (3) and the screw (9), whereby axial movement of the rod (20) with respect to the screw (9) causes the locking balls (18) to move from radially outer positions, in which the controlled member (3) is axially locked to the screw (9), to radially inner positions in which the controlled member (3) is axially released from the screw (9). An intermediate stem (16) is slidable in a passage (15) formed through the screw (9). The stem (16) transmits the axial movements of the control member (1) to the controlled member (3) when the latter is axially released from the screw (9).