A rotation angle detection device including: an angular position calculation unit configured to calculate angular position information representing an angular position of the motor rotation shaft based on a first sensor signal of the first sensor; an rotation number detection unit configured to detect a rotation number of the motor rotation shaft based on a second sensor signal of a second sensor and outputs rotation number information representing the rotation number; a rotation angle calculation unit configured to calculate rotation angle information indicating a rotation angle of the motor rotation shaft based on the angular position information and the rotation number information; and a power supply unit configured to stop supplying power to the first sensor, the angular position calculation unit and the rotation angle calculation unit and to supply power to the second sensor and the rotation number detection unit when the power switch is off.

An embodiment may provide a sensing device comprising: a rotor; a stator disposed outside the rotor; and a sensor module disposed outside the stator, wherein the rotor includes a rotor holder, and a magnet and a sleeve which are coupled to the rotor holder, wherein the magnet includes a first body and a first protrusion protruding in an axis direction from the first body, the sleeve includes a second body and a second protrusion protruding outward from the second body, and the rotor holder includes a first groove in which the first protrusion is disposed.

Provided is a torque sensor and an electric power steering system, which are capable of suppressing a detection property fluctuation between two magnetic sensors. A retaining portion is disposed at first and second magnetism collecting members in such a position as to be magnetically symmetrical with respect to first and second magnetic sensors.

The invention relates to a sensor apparatus, comprising: at least one ferromagnetic element, which, in an operating state, can be arranged on a torque transmission apparatus; and a measuring apparatus, which has at least one measuring element. Each measuring element is configured to measure a ferromagnetic resonance frequency of at least one ferromagnetic element. The measuring apparatus is configured to determine a torque of the torque transmission apparatus on the basis of so a shift in the measured ferromagnetic resonance frequency. The invention further relates to a method for determining a torque of a torque transmission apparatus.

A magnetic detection device includes a substrate including a penetration part, a magnetic detection part supported on the substrate to overlap the penetration part, a pair of magnetic guiding parts arranged to sandwich the penetration part and the magnetic detection part, the pair of magnetic guiding parts being configured to guide a magnetic flux from a magnetic generation part to the magnetic detection part, and a soft magnetic member at least partially provided inside the penetration part.

A sensor device includes a partial assembly, a circuit board, and a sensor housing. The partial assembly is constituted by selectively mounting a part that is at least one of a magnetism collection member and a driven wheel to a holder. The circuit board is provided with a detector configured to detect at least one of magnetic flux induced by the magnetism collection member and a rotational angle of the driven wheel in accordance with the part mounted to the holder. The sensor housing is penetrated by the shaft, and houses the partial assembly and the circuit board.

The power control unit sets a drive interval for driving the sensor by providing power intermittently to the sensor to a first time interval when no change is detected in the sine-wave signal and the cosine-wave signal, sets to the second time interval that is shorter than the first time interval when a change in only one of the sine-wave signal and the cosine-wave signal is detected, and sets to the third time interval that is shorter than the second time interval when a change in one of the sine-wave signal and the cosine-wave signal is detected and then a change in the other is detected.

A torque sensor unit includes a ring magnet that is connectable to a first partial shaft in a torque-proof manner, a magnetic yoke that is connectable to a second partial shaft and that is arranged in a magnetic field of the ring magnet, magnetic flux conductors that are connectable to the second partial shaft and that conduct magnetic fluxes generated by the magnetic yoke, a sensor unit having a first housing, which detects a change in rotational angle between the partial shafts by measuring magnetic flux density generated between the magnetic flux conductors, and a second housing that surrounds the ring magnet, the magnetic yoke, the magnetic flux conductors, and the sensor unit. The second housing may include a housing opening that is at least partly closed by a housing cover. The second housing and the housing cover may comprise magnetically conductive material for magnetically shielding the torque sensor unit.

The power management unit supplies first power that is continuous power to the second sensor when the power switch is on, supplies second power that is intermittent power having a voltage lower than the first power to the second sensor when the power switch is off, and outputs rotation number information representing a rotation number of the motor rotation shaft based on the second sensor signal. The power management unit includes a comparator that operates using the second power as the power source when the power switch is off and compare the second sensor signal and the reference voltage, and a counter that detects the rotation number of the motor rotation shaft by counting the output of the comparators.

A torque detection device includes an inner ring, a middle ring, an outer ring, a first beam, a second beam, a magnetic target, and a magnetic sensor. The first beam is composed of an elastic member extending in a radial direction so as to couple the inner ring and the middle ring together. The second beam is composed of an elastic member extending in a radial direction so as to couple the middle ring to the outer ring together. The magnetic target is fixed to the inner ring and the magnetic sensor is fixed to the middle ring such that the magnetic target and the magnetic sensor face each other. Torque acting on the inner ring or the outer ring is calculated according to how an amount of magnetism sensed by the magnetic sensor changes.