Patent ID: 8381442

Claim:
A hand-pulling drive mechanism for an industrial door, the mechanism being installed on a motor end cover of a motor used to move the industrial door upward or downward, comprising a hand drive device for users to manually operate the mechanism and a shaft connected with the hand drive device, the hand pulling drive mechanism further comprising: a gear pair having an engagement state and a disengagement state, comprising a drive gear sleeved on the shaft to switch between the two states, and a follower gear secured to a motor shaft; a rotation propelling device connected with the shaft to cause rotation of the drive gear, the rotation propelling device being moveably connected with the drive gear; an eccentric pulling device comprising a shaft pin radially positioned on the shaft and a torsion jacket pivotally connected to the shaft and capable of rotation relative to the shaft pin, wherein the torsion jacket and the drive gear rotate together such that rotation of the shaft pin relative to the torsion jacket causes axial movement of the torsion jacket and the drive gear during rotation of the shaft, thereby leading to engagement and disengagement between the drive gear and the follower gear; wherein, the rotation propelling device comprising: a feeding tube fixedly connected to the shaft so that rotation of the shaft causes the drive gear to move axially relative to the shaft and rotate with the feeding tube; a torsion spring engaged with the feeding tube urging the feeding tube and the shaft to return to an original position when the feeding tube is rotated from said original position; one end surface of the drive gear includes a first toothed portion whose teeth project parallel to a longitudinal axis of the drive gear, whereas one end surface of the feeding tube includes a second toothed portion engaged with the first toothed portion.