Patent ID: 7555963

Claim:
A torque sensor comprising: a first shaft having a first shaft central axis; a second shaft; a torsion bar connecting the first shaft and the second shaft together at first and second ends of the torsion bar; a magnetism generation portion mounted onto the first shaft so as to surround an outer circumference of the first shaft, the magnetism generation portion producing a magnetic flux in a direction of the central axis of the first shaft; a first magnetic yoke and a second magnetic yoke, each mounted onto the second shaft with a magnetic gap between them; and a magnetic sensor operable to detect magnetic flux in the magnetic gap between the first magnetic yoke and the second magnetic yoke; wherein the first magnetic yoke and the second magnetic yoke are positioned to guide the magnetic flux into the magnetic gap; wherein the first magnetic yoke, the second magnetic yoke, and a sleeve that includes a central sleeve opening from a first end surface of the sleeve to a second end surface of the sleeve are molded together with a resin to form a magnetic yoke assembly with a central insertion hole through the magnetic yoke assembly from a first end of the magnetic yoke assembly to a second end of the magnetic yoke assembly; wherein the first end surface of the sleeve is exposed at the first end of the magnetic yoke assembly; wherein the second end surface of the sleeve is partially exposed by at least one notch formed in an inner surface inside the central insertion hole of the magnetic yoke assembly; and wherein the notch is configured to receive a pressing surface of an assembly jig, and wherein the pressing surface of the assembly jig is configured to bear against a portion of the second end surface of the sleeve that is exposed inside the notch at a time when the magnetic yoke assembly is press-fit onto the second shaft.