| 摘要 |
PROBLEM TO BE SOLVED: To provide a reduction gear for an electric power steering device having high reliability, especially having excellent dimensional stability necessary for a worm wheel. SOLUTION: This reduction gear for the electric power steering device for transmitting output of a steering assistant output-generating electric motor to a steering shaft has the worm wheel integrated with a resin part formed with gear cogs on the peripheral face, on the periphery of a metal core pipe. A resin component of the resin part is composed of at least a compatible resin component of a high water absorptive polyamide resin selected from a polyamide 6, a polyamide 66 and a polyamide 46, and a low water absorptive polyamide resin selected from a polyamide 12, a polyamide 11, a polyamide 612, a polyamide 610, an aromatic polyamide and a denatured polyamide 12. |
