Worm gear drive with axially split drive worm - has adjustable spacer to prevent worm wheel backlash

摘要

A worm wheel gear drive has a drive shaft (25) which carries two worm bushes (23, 24). The two worms are separated by a radial spacer flange (26). The worm wheel teeth (17) are in contact with the helix on each worm bush. - When the drive shaft (25) rotates in one direction, the helix flank of one worm bush (23) produces a tangential force on the worm wheel which causes it to rotate. The facing helix flank of the second worm bush (24) is in contact with the opposite side of the gear wheel teeth. Thus by spacing the axial distance between the two worm bushes, any play between worm and worm wheel can be eliminated. When the drive shaft rotates in the opposite direction, the function of the two worm bushes is reversed.