To prevent play from generating even in a component having a cylindrical bearing formed with fixed draft by forming a plurality of ribs having no gradient on the extreme ends on the inner face of the cylindrical bearing.

The inner face of a cylindrical bearing 2 is integratedly formed with four ribs 6 along the lengthwise direction of the cylindrical bearing 2. The rib 6 is formed into a triangular shape gradually enlarging the cross section from the extreme end part of the cylindrical bearing 2 toward the base end part side and forming the extreme end angle into 45°. Consequently, the extreme end of the rib 6 is without gradient (in parallel with a shaft 3 or nearly in parallel with it) and it is closely stuck to the outer face of the shaft body 3. Accordingly, the cylindrical bearing 2 itself is formed with fixed draft θ, but the shaft body 3 inserted into the cylindrical bearing 2 is prevented from playing in the radial direction.