A magnetic field sensor for detecting motion of an object includes one or more magnetic field sensing elements configured to generate a magnetic field signal in response to a magnetic field associated with the object. A motion detector responsive to the magnetic field signal and to a threshold signal is configured to generate a detector output signal having edges occurring in response to a comparison of the magnetic field signal and the threshold signal. A speed detector responsive to the detector output signal generates a speed signal indicative of a speed of motion of the object. A delay processor is responsive to the speed signal and configured to determine a delay for the detector output signal based on the speed of motion of the object.

A manufacturing error and a mounting error of a position sensor used for detection of a rotation angle of a rotary shaft are appropriately calibrated to improve detection accuracy of the rotation angle. Therefore, an angle detection device 1 includes at least a first crank angle sensor 1211 and a second crank angle sensor 1212 provided to be capable of detecting a rotation angle of a rotary shaft of a crankshaft 123, and includes: a gain corrector 4 that corrects at least any one of gains G1 and G2 of the first crank angle sensor 1211 and the second crank angle sensor 1212 such that an amplitude ya of a differential signal S41b of the first crank angle sensor 1211 is equal to an amplitude yb of a differential signal S42b of the second crank angle sensor 1212; and a phase corrector 5 that corrects at least any one of a phase a of the differential signal S41b and a phase b of the differential signal S42b such that the phase a of the differential signal S41b is equal to the phase b of the differential signal S42b.

Disclosed is a method for calibrating a crankshaft sensor, of the type including a crankshaft wheel and a sensitive element facing the latter, during replacement of the crankshaft sensor, including the following steps: saving an old angular position of a camshaft sensor wheel relative to the crankshaft wheel, which is achieved using the old crankshaft sensor, replacing the old crankshaft sensor with a new crankshaft sensor, determining a new angular position of the same camshaft sensor wheel relative to the crankshaft wheel, which is achieved using the new crankshaft sensor, correcting the measurement of the crankshaft sensor by applying an offset equal to the difference between the new angular position and the old angular position.

An angle detector for detecting an amount of angular change due to the rotation of a rotary body. The angle detector is provided with a rotary body rotating around a rotation axis, a graduated scale having a plurality of graduations along the circumference of the rotary body in a rotation direction, and a plurality of sensors disposed along the circumference. Each of the sensors outputs a signal according to an amount of angular change on the basis of the plurality of graduations. The output signal includes a fundamental wave component having one of the plurality of graduations as a first period first order, and a harmonic wave component having an order that is an integer multiple of at least two times the fundamental wave component. An amount of angular displacement calculated from the output signal includes an angular error component that is due to the harmonic wave component and has an order component that is an integer multiple of the one graduation that is the first period first order. The number of the plurality of sensors is determined on the basis of the number of graduations on the graduated scale and the order component of the angular error component.

A magnetic sensor may detect a system-level error, associated with a sensor system that includes the magnetic sensor, based on one or more physical parameters as determined at the magnetic sensor. The magnetic sensor may provide an indication of the system-level error in an output signal. The one or more physical parameters may include a temperature at the magnetic sensor, a temperature drift of the magnetic sensor, a supply voltage at the magnetic sensor, an amount of humidity at the magnetic sensor, or an amount of pressure at the magnetic sensor.

A digital displacement sensor and a displacement measuring method thereof, pertaining to the technical field of displacement sensors. The digital displacement sensor includes a housing and a circuit board, and the circuit board is arranged inside the housing. The housing is provided with a window and an opening. The circuit board is provided with a signal acquisition module, an analog front end circuit, a digital compensation circuit, and a signal output interface. The digital displacement sensor allows to alternatively fix the sensor or measured object according to the structure. The measurement can be performed as long as a relative movement between the sensor and the measured object occurs. Factors such as material of the measured object etc. are not limited, so materials such as steel belts, aluminum plates, plastics etc. can be flexibly used. Merely surfaces of the measured object need to be coated with corresponding stripes.

A rotation detecting device includes first and second magnetic detection elements that output first and second signals and a detection circuit having the first and second signals input thereto. The detection circuit includes an automatic correction circuit that performs generating and updating of a correction value for correcting the and second signals. The automatic correction circuit is configured to stop the generating or the updating of the correction value in at least one of a case where a rotation direction of an object is changed to a reverse rotation direction from a normal rotation direction and a case where a rotation direction of the object is changed to the normal rotation direction from the reverse rotation direction.

An angle measuring device includes first and second component groups and a bearing. The first component group includes a scale element having first and second graduations. The second component group has a first modular unit, having a position sensor, a second modular unit, having first to sixth position transducers, and a compensation coupling. To determine the relative angular position between the component groups, the first graduation is scannable with the aid of the position sensor. Using the first to third position transducers, the first graduation or a further graduation disposed on the scale element is scannable to determine a displacement of the scale element in a plane. Using the fourth to sixth position transducers, the second graduation is scannable to determine tilting of the scale element about a tilting axis, the position sensor being situated in a torsionally stiff but axially and radially flexible manner relative to the position transducers.

An angle measuring device includes first and second component groups and a bearing. The first component group includes a scale element having a first graduation. The second component group has a first modular unit, including a position sensor, and a second modular unit, including first, second, and third position transducers, and a compensation coupling. The first and second modular units are connected in a torsionally stiff but axially and radially flexible manner. The angle measuring device is operable in first and second modes. In the first mode, the first graduation is scannable by the position sensor to determine a first angular position. In the second mode, the first graduation or a further graduation situated on the scale element is scannable by the position transducers to determine further angular positions. A corrected relative angular position is determinable based on the first angular position and the further angular positions.

In order to provide a detection device that can accurately detect thermal deformation in any state including a case where thermal deformation has already occurred, there is provided a detection device which includes: a scale with a strained grating; and two sensor heads mounted on a pedestal at a predetermined distance, the sensor heads detecting positions on the scale based on the grating. Thermal deformation of the pedestal or the scale is detected based on a change in a difference between the positions detected by the two sensor heads.