Patent ID: 7611206

Claim:
A lift device, comprising: an outer pipe; a guide track secured in the outer pipe and having two opposite sides each formed with a plurality of locking grooves; an inner pipe movably mounted in the guide track; a follower having an upper end secured to a lower end of the inner pipe to move with the inner pipe; a locking member pivotally mounted in a lower end of the follower and having two opposites ends each formed with a locking portion protruding from the follower and detachably locked in one of the locking grooves of the guide track to detachably lock the follower and the inner pipe in the guide track; a pull handle movably mounted in the inner pipe and having a lower end which is movable to press and pivot the locking member toward the guide track so as to lock the locking portion of the locking member in one of the locking grooves of the guide track; a control knob movably mounted on an upper end of the inner pipe and connected to an upper end of the pull handle to move the pull handle to press or detach from the locking member; a restoring spring mounted on the pull handle and biased between the follower and the lower end of the pull handle to push the lower end of the pull handle toward the locking member.