Patent ID: 9157519
Filing Date: 2015-10-13
Classification: F16H,Y10T

Abstract:
1. A worm reduction gear configured to reduce a rotation of a worm and transmit the reduced rotation to a worm wheel, the worm reduction gear comprising: a worm configured to rotate axially, a worm wheel configured to be driven to rotate by being meshed with the worm, a casing that houses the worm and the worm wheel, wherein the casing comprises: a wheel opposing surface that opposes an end surface of the worm wheel via an interval; and a grease holding recessed portion formed in a recessed shape in the wheel opposing surface and facing a worm meshing portion between the worm and the worm wheel, and wherein the grease holding recessed portion comprises: a recessed portion bottom surface opposing the end surface of the worm wheel; and a recessed portion side face extending from the recessed portion bottom surface to the wheel opposing surface, wherein the recessed portion side face is formed in an arc shape which opens towards the worm meshing portion, and wherein the casing comprises: a gear housing that houses the worm wheel; and a lower cover encapsulating the gear housing, the lower cover includes a disc-shaped wheel opposing base portion including the wheel opposing surface that opposes the end surface of the worm wheel, the grease holding recessed portion is formed in a recessed shape in a side portion of the wheel opposing base portion, and the recessed portion side face is formed around the worm meshing portion.