Patent ID: 8715132

Claim:
A linear actuator comprising: a housing, a linear output member axially movable from a retracted position within the housing, the linear output member comprising a radial groove; and a rotary lock assembly disposed within the housing and constrained from axial motion, the rotary lock assembly comprising: a generally tubular rotor having an inner surface and an outer surface, the rotor disposed surrounding the radial groove of the linear output member when the linear output member is in the retracted position, the rotor being capable of rotation from a first rotor position to a second rotor position, the inner surface of the rotor including a plurality of axial rotor grooves, each axial rotor groove having a rounded surface with a radius of curvature defining an outer radius of the axial rotor groove and radially angled surface between the outer radius of the axial rotor groove and an innermost radius of the rotor; a lock capable of radial displacement disposed within a bore of the rotor, the lock responsive to rotation of the rotor to the first rotor position to engage the radial groove and prevent axial motion of the output member from the retracted position; the radial groove of the linear output member including an axially angled, substantially planar surface; the lock configured to include an axially angled surface shaped complimentary to axially angled, substantially planar surface of the radial groove, a substantial portion of the axially angled surface of the lock being in contact with a substantial portion of the axially angled, substantially planar surface of the radial groove, when the lock is in a locked position; the lock configured with a crown having a first portion and a second portion, the second portion extending radially outward from the first portion, the second portion having a rounded outer surface with a radius of curvature substantially the same as a radius of curvature of the inner surface of the rotor; the crown further configured with a radially angled surface between the first portion and the second portion, the radially angled surface having an angled complementary to an angled of one of the radially angled surfaces between the outer radius of the axial rotor groove and the innermost radius of the rotor; wherein a substantial portion of the rounded outer surface of the second portion of the lock corresponds to and is in contact with the inner surface of the rotor, when the lock is in the locked position; and wherein the one of the radially angled surfaces between the outer radius of the axial rotor groove and the innermost radius of the rotor is corresponding to and in substantial contact with the radially angled surface between the first portion and the second portion of the crown when the lock is in an unlocked position.