| 摘要 |
An eccentric guide surface portion (48), which has a shape of a partially cylindrical surface, is formed at a front end portion of a second cylindrical surface portion (32a), into which a torque detecting coil unit (31a) is fitted and fixed, of an inner peripheral surface of a housing body (16a) that is joined and fixed to a front end portion of a steering column. The center of curvature of the eccentric guide surface portion (48) is offset to a side opposite to a connection hole (39a), which is formed at the housing body (16a), in a radial direction so that a connection terminal (36a) of the torque detecting coil unit (31a) is connected to a circuit board (40a). Accordingly, a torque measuring unit for an electric power steering device, of which the size and weight are reduced while good assembly workability is ensured, is obtained. |
| 主权项 |
1. A torque measuring unit for an electric power steering device, comprising:
a housing that includes a housing body and a lid body fixed to the housing body; an input shaft and an output shaft that are rotatably supported in the housing and are coaxially connected to each other by a torsion bar; a rolling bearing that is fitted and fixed into a first cylindrical surface portion formed at one end portion of an inner peripheral surface of the housing body in an axial direction and supports the output shaft so as to allow the output shaft to be rotatable relative to the housing body; and a torque detecting coil unit that is fitted and fixed into a second cylindrical surface portion having a diameter smaller than a diameter of the first cylindrical surface portion and formed closer to the other side of the inner peripheral surface of the housing body in the axial direction than the first cylindrical surface portion so as to be concentric with the first cylindrical surface portion, and detects a direction and a magnitude of torque applied to the input shaft, wherein the torque detecting coil unit includes an annular detection body that includes a coil, and a connection terminal which is provided at a portion of the detection body in a circumferential direction so as to protrude outward in a radial direction, and a distance between a center of the detection body and an end edge of the connection terminal is larger than a half of an outer diameter of the rolling bearing, a connection hole, which is formed in the radial direction, is formed at a portion matching the second cylindrical surface portion in the axial direction on a part of the housing body in the circumferential direction, a recessed groove, which is recessed outward in the radial direction, is formed at a portion, of which a phase corresponds to a phase of the connection hole in the circumferential direction, of the inner peripheral surface of the housing body between the connection hole and the first cylindrical surface portion in the axial direction, an eccentric guide surface portion, which has a shape of a partially cylindrical surface and of which a center of curvature is offset to a side opposite to a side on which the connection hole is formed in the radial direction, is formed at one end portion of the second cylindrical surface portion in the axial direction, and the eccentric guide surface portion and the second cylindrical surface portion are continuous in an axial direction through a stepped surface. |
