Linear actuator with translating screw and torque tube

A linear actuator, comprising:

• a housing;
• a motor disposed within the housing and having a tubular motor shaft configured for rotation about an axis;
• a ball nut disposed within the housing and configured for rotation about the axis, the ball nut axially spaced from the motor shaft;
• a torque transfer assembly configured to transfer torque from the motor shaft to the ball nut, the torque transfer assembly including
• a torque transfer tube configured for rotation about the axis and having first and second axial ends, the first axial end coupled to the motor shaft for rotation therewith;
• and,
• a first coupling between the second axial end of the torque transfer tube and the ball nut, the first coupling configured for rotation with the ball nut and the torque transfer tube;
• and,
• a ball screw extending through at least a portion of the motor shaft, the torque transfer tube and the ball nut and outward from the housing, the ball screw configured for movement along the axis in response to rotation of the ball nut
• wherein the first coupling is configured for movement along the axis relative to the torque transfer tube in the presence of a load applied to the ball screw in the direction of the axis and
• further comprising a brake disposed within the housing and configured to apply a braking torque to the motor shaft
• wherein the ball screw extends through at least a portion of the brake.

A linear actuator, comprising:

• a housing;
• a motor disposed within the housing and having a tubular motor shaft configured for rotation about an axis;
• a ball nut disposed within the housing and configured for rotation about the axis, the ball nut axially spaced from the motor shaft;
• a torque transfer assembly configured to transfer torque from the motor shaft to the ball nut, the torque transfer assembly including
• a torque transfer tube configured for rotation about the axis and having first and second axial ends, the first axial end coupled to the motor shaft for rotation therewith;
• and,
• a first coupling between the second axial end of the torque transfer tube and the ball nut, the first coupling configured for rotation with the ball nut and the torque transfer tube;
• and,
• a ball screw extending through at least a portion of the motor shaft and through the torque transfer tube and the ball nut and outward from the housing, the ball screw configured for movement along the axis in response to rotation of the ball nut
• wherein a first radially extending surface formed in an axial end of one of torque transfer tube and the first coupling faces a second radially extending surface of the other of the torque transfer tube and the first coupling and the first and second radially extending surfaces are axially spaced from one another by an air gap.