Disclosed is a step actuator. The step actuator includes a housing; a stator installed in the housing; a rotor positioned radially inward from the stator, the rotor rotating and protruding from one side of the housing; a bearing installed at one side of the housing so as to be coupled with the rotor; a bearing cover coupled with one side of the housing to restrain movement of the bearing; a screw member coupled with the rotor to linearly move according to rotation of the rotor; and a mounting member coupled to the bearing cover to support the screw member.

Disclosed is a step actuator. The step actuator includes a housing; a stator installed in the housing; a rotor positioned radially inward from the stator, the rotor rotating and protruding from one side of the housing; a bearing installed at one side of the housing so as to be coupled with the rotor; a bearing cover coupled with one side of the housing to restrain movement of the bearing; a screw member coupled with the rotor to linearly move according to rotation of the rotor; and a mounting member coupled to the bearing cover to support the screw member.

An actuator includes a ball nut, a ball screw, and a ball screw stop. The ball nut is adapted to receive an input torque and in response rotates and supplies a drive force. The ball screw extends through the ball nut and has a first end and a second end. The ball screw receives the drive force from the ball nut and in response selectively translates between a retract position and a extend position. The ball screw stop is mounted on the ball screw proximate the first end to translate therewith. The ball screw stop engages the ball nut when the ball screw is in the extend position, translates, with compliance, a predetermined distance toward the first end upon engaging the ball nut, and prevents further rotation of the ball screw upon translating the predetermined distance.