Patent ID: 9546725
Date: 2017-01-17
CPC Classifications: B21K,B23P,F16D,F16H,Y10T

Claim:
1. A press-fit structure in which one of end faces of a gear in a central axis direction is placed in contact with a protrusion formed to protrude outward from an outer peripheral surface of an annular component in a radial direction of the annular component, and an inner peripheral surface of the gear is press-fitted on the outer peripheral surface of the annular component, wherein the press-fit structure includes a tensile stress reducing mechanism to reduce tensile stress in a position of at least the one end face of the gear, the tensile stress being generated in a tooth-root portion of the gear when the inner peripheral surface of the gear is press-fitted on the outer peripheral surface of the annular component, wherein the tensile stress reducing mechanism is configured so that a press-fit allowance between the inner peripheral surface of the gear and the outer peripheral surface of the annular component and in the position of the one end face of the gear is set smaller than a press-fit allowance between the inner peripheral surface of the gear and the outer peripheral surface of the annular component and in a position of the other end face of the gear in the central axis direction, and wherein the inner diameter of the gear in the position of the one end face and the inner diameter in the position of the other end face are set at a ratio equal to a ratio of a tensile stress generated in the position of the one end face and a tensile stress generated in the position of the other end face in a case wherein the inner diameter of the gear is constant.