ROTATION TRANSMISSION MECHANISM AND ELECTRIC POWER STEERING DEVICE

摘要

Provided are an electric power steering device and a rotation transmission mechanism having a split structure and enabling a reduction in processing costs. For example, when connecting, by means of a torsion bar (4), an input side shaft (first rotating shaft) (2) and an output side shaft (second rotating shaft) (3), positioned on the same axis in an electric power steering device, the input side shaft (2) is configured as a several-portion connection structure that is split into a torsion bar interlocking section (20a) which is a common portion that can be commonly used in different products, and a connection section (20b) which is a specialized-portion for a specific product. The torsion bar interlocking section (20a) and the connection section (20b) are joined by means of serration press-fitting; and a thin-walled section (23a), which serves as a swage section, is provided to the torsion bar interlocking section (20a) (or the connection section (20b)), the thin-walled section (23a) being swaged to the connection section (20b) (or the torsion bar interlocking section (20a)) and serving as a backup for the serration press-fitting.