A cam guiding device includes a cam guide having a cylindrical portion, a partially cylindrical portion extending from a leading end portion of the cylindrical portion, a partially tapered portion extending from the leading end portion of the cylindrical portion, and a rotation stopper portion provided on the partially cylindrical portion, and a sleeve for accommodating the cam guide. The sleeve includes an arc portion that overlaps the partially cylindrical portion from an outside. A radius of the partially tapered portion increases as the partially tapered portion extends away from the cylindrical portion. The rotation stopper portion is a component that protrudes radially outward from an outer circumferential surface of the partially cylindrical portion. When the rotation stopper portion abuts the sleeve and an inner circumferential surface of the cam guide abuts the parking cam, rotation of the cam guide with respect to the sleeve is restricted.