Patent ID: 7661332

Claim:
A worm reducer comprising: a worm having a screw face on an outer circumferential surface thereof, said worm having a first longitudinal axis; and a worm wheel having worm wheel teeth formed on a circumferential surface thereof, the worm wheel teeth meshing with the screw face of the worm, said worm wheel having a second longitudinal axis, wherein: a rotation of the worm is reduced and transmitted to the worm wheel, a lead angle of the worm wheel is smaller than that of the worm, a diameter of the tooth tip circle of the worm is constant, a diameter of the tooth base circle of the worm is constant, respective lead angles of the teeth on the worm are the same, and an axis-crossing angle, defined by an angle between the first longitudinal axis of the worm and the second longitudinal axis of the worm wheel, is greater than zero.