Patent ID: 7268449

Claim:
A linear actuator, comprising: a stator assembly shaped into a cylinder defining a hollow, the stator assembly including a plurality of windings, a plurality of stator yokes each having an array of pole teeth which constitute an inner circumference of the stator assembly, and which are excited by the windings, and a yoke support member formed of resin by injection-molding, and integrally supporting the windings and the stator yokes; a housing disposed at a front end of the stator assembly; a rear end cap disposed at a rear end of the stator assembly, the rear end cap being formed of resin simultaneously and integrally with the yoke support member; a rotor assembly shaped into a hollow-cylinder, and rotatably housed in the hollow of the stator assembly, the rotor assembly including a ring-shaped magnet having a plurality of magnetic poles, constituting an outer circumference of the rotor assembly, and opposing the pole teeth of the stator assembly with a predetermined distance therebetween, and a female screw disposed at an inner circumference of the rotor assembly; an output shaft having a male screw formed at a rearward portion thereof and threadedly engaging with the female screw of the rotor assembly, the output shaft being inserted through the rotor assembly; a stopper pin secured to the output shaft, and axially controlling mode and amount of movement of the output shaft initiated by rotation of the rotor assembly; and a bearing member fitted inside the housing for rotatably supporting the rotor assembly, the bearing member having a groove formed at its inner circumference so as to extend parallel to the length of the output shaft with one end of the groove being blind so as to constitute a stopper member positioned between the stopper pin and the rotor assembly in an axial direction.