Patent ID: 7458562

Claim:
An extendible and retractable actuator, comprising: an extendible and retractable sleeve assembly; a motor mounted in one sleeve of the extendible and retractable sleeve assembly, a shaft of the motor protruded out of both ends of the motor; a first screw connected to one end of the shaft of the motor, the extending direction of the first screw corresponds to the moving direction of the extendible and retractable sleeve assembly, the first screw being engaged with one end of the extendible and retractable sleeve assembly and rotated by the motor to drive one end of the extendible and retractable sleeve assembly to extend and retract; a gear box connected to the other end of the shaft of the motor; and a second screw fixed to the other end of the extendible and retractable sleeve assembly and engaged with the gear box, the gear box being driven by the motor to move relative to the second screw, so as to drive the other end of the extendible and retractable sleeve assembly to extend and retract.