Speed-reducing gear comprising a worm and a worm wheel

摘要

The worm and wheel speed reduction gear has an endless screw (1) with a hollowed out semi-circular form (7) driving a helical gear (11) which also has semi-circular hollowed out gear teeth (19). The drive is transmitted from the endless screw to the helical gear by closely packed spherical balls (6) which run in the semi-circular tracks. After passing along the working section of the gear pair, the balls are collected by curved scoops (9, 10) and are returned to the other end of the screw along an internal passage (8). The balls are retained in the screw recesses by two annular collars (14, 15) pinned (16, 17) to the worm wheel shaft and an outer stationary sleeve (5).