Patent ID: 8138646

Claim:
A rotatable shaft assembling method comprising: installing at least one plain bearing over a rotatable shaft; and inserting the rotatable shaft together with the at least one plain bearing into a housing in a predetermined inserting direction, which is generally parallel to an axial direction of the rotatable shaft, such that the at least one plain bearing is respectively press fitted into at least one installation part of the housing, wherein: the inserting of the rotatable shaft includes moving at least one pressing and supporting element, which is provided in at least one of the rotatable shaft and an assembling jig, in the predetermined inserting direction to respectively press fit the at least one plain bearing into the at least one installation part of the housing; the installing of the at least one plain bearing over the rotatable shaft includes installing one of the at least one plain bearing to an end portion of the rotatable shaft, which is located at a front side of the rotatable shaft in the predetermined inserting direction; and the moving of the at least one pressing and supporting element includes moving one of the at least one pressing and supporting element, which is provided in the rotatable shaft, in the predetermined inserting direction to press fit the plain bearing, which is installed to the end portion of the rotatable shaft, into one of the at least one installation part of the housing, further comprising: moving the rotatable shaft in an opposite direction, which is opposite from the predetermined inserting direction, to provide a gap between the plain bearing, which is installed to the end portion of the rotatable shaft, and the pressing and supporting element, which is provided in the rotatable shaft, after the moving of the pressing and supporting element, which is provided in the rotatable shaft, in the predetermined inserting direction, wherein the moving of the rotatable shaft in the opposite direction includes applying an axial force to the end portion of the rotatable shaft in the opposite direction.