A device for the measurement of the angular position of a shaft, having: a support upon which a primary winding and at least two secondary windings in mutual phase opposition are configured, to form a first inductive positional sensor, and a second positional sensor having at least two secondary windings in mutual phase opposition and arranged on the same support, opposite the secondary windings of the first positional sensor with respect to a median line, such that a motif is formed in each case on either side of the median line, wherein the primary winding encloses all the secondary windings. A unit having a device of this type and a target having two helixes of opposing pitches.

A rotary encoder may include a magnetic encoder disc having a plurality of magnetic features added to the disc by additive manufacturing distributed over a surface of the encoder disc, wherein the disc is configured for attachment to the end of a rotatable shaft, or a cylindrical metallic encoding feature having a plurality of magnetic features added to the cylindrical encoder by additive manufacturing distributed over the surface of the cylindrical encoding feature, wherein the encoding feature is capable of attachment to an outer diameter of the rotatable shaft. The encoder additionally includes a magnetic sensor positioned adjacent to the end of the rotatable shaft to detect magnetic signals from the magnetic features on the disc and/or positioned over the surface of the rotatable shaft to detect magnetic signals from the magnetic features on the encoding feature.

The invention relates to a system having a coder with a magnetic track that exhibits an alternation of North and South magnetic poles separated by i Archimedean spiral transitions. The invention also includes a rotation sensor able to detect the periodic magnetic field emitted by the coder using several sensitive elements, the sensitive elements being distributed angularly along the magnetic track while forming between at least two sensitive elements an angle which is designed so that the signals delivered by the elements are in quadrature.

Various embodiments are directed to an angle position sensor system for detecting angle position of a movable member along a defined path comprising: an arc magnet array defining an arc path and configured to be coupled to the movable member. The arc magnet array comprising at least two magnetized pole layers arranged in a spiral pattern and having a tilt angle. A magnetic field sensor disposed proximate to the arc magnet array and movable relative to the magnetic field sensor. The magnetic field sensor configured to generate one or more periodic position signals having N number of periods per arc cycle along the arc path. The magnetic field sensor configured to transmit the one or more periodic position signals to a controller associated with the movable member. The angle position of the movable member is determined based at least in part on the one or more periodic position signals.

Disclosed is a linear inductive sensor having, on the one hand, a fixed part of transformer type with a primary circuit and at least two secondary circuits, the primary circuit being flowed through by a high-frequency alternating current capable of inducing an electrical voltage in each of the at least two secondary circuits and, on the other hand, a moving part with a target intended to be fixed on a mechanical component executing a movement in rotation about an axis, which the inductive sensor measures angularly. The target is a metal spiral carried by a circular face of a ring having a central recess, the ring being intended to be fixed on the component while being concentric therewith, the spiral projecting axially from the ring while making at least one revolution around and moving away from the recess.

This inductive position sensor is designed to measure the angular position of a shaft or the like and includes a support on which are realized, on the one hand, a primary winding, and on the other hand, at least two secondary windings in phase opposition with respect to each other. Each secondary winding is defined by a set of at least two loops in phase with each other. The secondary windings are connected in series and each arranged symmetrically with respect to a middle line so as to form each time a pattern on either side of this middle line, the two patterns having a separation between them in the area of said middle line. An assembly including such a sensor and a target with two oppositely directed helices.

A device for the measurement of the angular position of a shaft, having: a support upon which a primary winding and at least two secondary windings in mutual phase opposition are configured, to form a first inductive positional sensor, and a second positional sensor having at least two secondary windings in mutual phase opposition and arranged on the same support, opposite the secondary windings of the first positional sensor with respect to a median line, such that a motif is formed in each case on either side of the median line, wherein the primary winding encloses all the secondary windings. A unit having a device of this type and a target having two helixes of opposing pitches.

A rotation angle detection device that is capable of detecting an absolute rotation position with a high accuracy without an error. A rotation detection target rotates together an operatable rotation member and has an outer scale and an inner scale. Two rotation detection elements are arranged at opposite positions across the rotation axis in the radial direction so as to respectively irradiate the outer and the inner scales with light beams and output signals corresponding to reflected components. A control unit calculates a rotation angle of the rotation detection target using the signals. The outer and inner scales are so formed that a signal output from one of the two rotation detection elements increases and the signal output from the other decreases when the rotation member is rotated.

An angle sensor is disclosed. The angle sensor has a disc, a first magnetic pattern disposed on a side of the disc and including a number N1 of first portions of spirals regularly distributed in a first ring, and a second magnetic pattern disposed on a side of the disc and including a number N2 of second portions of spirals regularly distributed in a second ring. The numbers N1 and N2 are coprime and N1 is different from N2, N21, and N2+1.

A magnetic field sensor includes a back bias magnet to generate a DC magnetic field. First and second magnetic field sensing elements of the magnetic field sensor are disposed proximate to at least one ferromagnetic surface of a ferromagnetic target object. The first and second magnetic field sensing elements generate first and second electronic signals, respectively, in response to first and second sensed magnetic fields corresponding to the DC magnetic field but influenced by the at least one ferromagnetic surface. The magnetic field sensor generates a difference signal that is a difference of amplitudes of the first and second electronic signals. The difference signal is indicative of a rotation measurement of an absolute relative rotation of the ferromagnetic target object and the magnetic field sensor about a rotation axis.