... transmission with rigid frame, special bearing and screw down worm gear with secondary enveloping surface.StructureIt is composed of main ... motor, gear reducer, double helical spur gear, universally-jointed axle, support, working seat, ... carbon steelSpeed of screw Dow gear0.058mm/sGear reducerZLYWorm gear for screw downA=315Double helical spur gearA:690; ...