Patent ID: 8881363

Claim:
A method for coupling two components together, which comprises: subjecting a softer member of the two components to shearing with a corner of a harder member of the two components while respective parts of the two components, positioning thereof being required, are kept in as-positioned state; fitting the two components together between a side face of the corner of the harder member, and a sheared surface of the softer member; and further coupling the two components together in a fitting surface where the two components are fitted; wherein the coupling in the fitting surface is effected by plastic coupling or press-fitting; the harder member is an outer cylindrical component with a bottom, having plural levels of steps on the inner surface thereof, and a tapered hole at the center of an inner bottom thereof while the softer member is in an inner cylindrical component having a through hole at the center thereof; a guide pin for positioning is inserted into the through hole of the inner cylindrical component until the guide pin is butted against the tapered hole of the outer cylindrical component with a bottom of the inner cylindrical component kept placed on the plural levels of the steps of the outer cylindrical component, thereby effecting tentative concentric positioning of both the through hole of the inner cylindrical component and the tapered hole of the outer cylindrical component, and the bottom of the inner cylindrical component is then interlocked by the plural levels of the steps of the outer cylindrical component by pressing down the inner cylindrical component while maintaining a clearance between the inside diameter of the outer cylindrical component and the outside diameter of the inner cylindrical component, so that the bottom of the inner cylindrical component is coupled to the outer cylindrical component by an auto-straining force as a residual stress occurring to a side face of at least one step among the plural levels of the steps; an inner peripheral surface of the outer cylindrical component and an outer peripheral surface of the inner cylindrical component are in contact together only at the plural levels of the steps located at the bottom of the inner cylindrical component, and a gap exists therebetween except for at the plural levels of the steps.