Torque sensor

Abstract

Provided is a torque sensor that allows a surface-mount magnetic sensor to be disposed between magnetic collection rings adjacent to each other in a radial direction with respect to a rotational axis. A torque sensor includes a rotational member including a first shaft and a second shaft connected to each other via a torsion bar, a first magnetic collection mechanism and a second magnetic collection mechanism each formed into a circular-arc shape along a direction around a rotational axis of the rotational member with use of a magnetic material and disposed so as to face each other in a radial direction of the rotational member, a surface-mount first magnetic sensor and second magnetic sensor inserted between the first magnetic collection mechanism and the second magnetic collection mechanism and each including a Hall element configured to detect a change in a magnetic field between the first magnetic collection mechanism and the second magnetic collection mechanism, and a sensor substrate on which the first magnetic sensor and the second magnetic sensor are mounted. The torque sensor detects a torque generated on the rotational member based on an output signal of the first magnetic sensor or the second magnetic sensor.