Patent ID: 8646352

Claim:
A worm wheel, comprising: a metallic core member including a pivot portion; and a gear forming member made of plastic material and formed on an outer periphery of the core member; wherein: the core member includes a boss portion defining the pivot portion, an intermediate portion extending radially from the outer periphery of the boss portion, and a cylindrical portion connected to a radially outer end of the intermediate portion and having the gear forming member molded thereon coaxially with the boss portion; the cylindrical portion is formed with a plurality of radially outward projections on an outer periphery thereof such that the projections are arranged circumferentially at a regular interval; the cylindrical portion is formed with a plurality of hollow portions passed radially therethrough such that a hollow portion is located between each adjacent pair of projections; and teeth formed on an outer periphery of the gear forming member are disposed at positions circumferentially coinciding with the hollow portions formed in the cylindrical portion.