Abstract: A rotation angle detection system comprises a magnet arranged to rotate around a rotation axis. A first magnetic detection circuit defines a first surface provided with a first and second pairs of magnetic detection elements. A signal processing unit is configured to output a signal representative of a rotation angle of the magnet based on outputs of the first and second pair of magnetic detection elements. A second magnetic detection circuit is provided with another first and second pairs of magnetic detection elements. The signal processing unit is configured to output a redundant signal corresponding to a rotation angle of the magnet based on outputs of the other first pair of magnetic detection elements and the other second pair of magnetic detection elements.

Abstract: To provide a displacement detection device and a continuously variable transmission that directly detect the position of the movable sheave. A displacement detection device includes a magnet that forms a magnetic field, a movable sheave that is rotated in a rotational direction and displaced in a direction perpendicular to the rotational direction and that is a measuring object having a concave portion (or a protrusion) on the circumferential surface, and a sensor disposed between the magnet and the circumferential surface of the movable sheave and detecting a change in magnetic flux density due to the displacement of the movable sheave in the magnetic field formed by the magnet and induced to the concave portion (or the protrusion).

Abstract: A torque sensor for sensing the torque applied to a first shaft has a multipolar magnet rotated therewith and is connected to a second shaft via a torsion bar. The torque sensor includes a pair of magnetic yokes adapted to be disposed in a magnetic field of the multipolar magnet and adapted to be rotated together with the second shaft. A magnetic detection element has a detection surface and is capable of detecting a magnetic flux in a direction parallel to the detection surface.

Abstract: A rotation detection device includes a rotatable body having a tooth tip and a tooth bottom on planes normal to a rotation axis direction, a magnet forming a magnetic field toward the tooth surfaces of the tooth tip and bottom, a magnetic detection element disposed between the rotatable body and the magnet and other than on the rotation axis of the rotatable body, and detecting the magnetic flux densities in the rotation axis direction of the rotatable body at at least two positions, and a magnetic sensor having a signal processor for calculating the rotation angle of the rotatable body according to difference between the magnetic flux densities in the rotation axis direction detected at two positions and difference between the magnetic flux densities in the direction perpendicular to the rotation axis direction and a radial direction of the rotatable body detected at two positions by the magnetic detection element.

Abstract: To provide a rotation detection device that has a miniaturized sensor IC in comparison with a prior art. A rotation detection device includes: a magnet that forms a magnetic field toward a tooth surface of a gear; and a sensor disposed between the magnet and the gear, the sensor including: at least a pair of magnetic detection elements x1 and x2 that outputs signals according to a magnetic flux density in a radial direction of the gear; and a magnetic concentrator that induces, in the radial direction of the gear, a component in a circumferential direction of the gear in the magnetic flux density on detection surfaces of the magnetic detection elements x1 and x2, the sensor detecting a variation in a magnetic flux density accompanying the rotation of the gear.

Abstract: Provided is a displacement detection device which reduces the influence of disturbance noise on a magnetic field to be detected and makes a range detectable by a monopole magnet wider than a pitch of a magnetic detection elements. A displacement detection device includes a magnet which is displaced in a displacement direction Ds, is rod-shaped and has a form in which a longitudinal direction and the displacement direction Ds form a predetermined angle ?, and a sensor IC in which magnetic detection element groups, which detect a magnetic flux density of a magnetic field formed by the magnet in an x direction and a z direction orthogonal to the displacement direction Ds, are arranged in pairs with a predetermined interval dp, and which outputs a difference between outputs of the magnetic detection element groups.

Abstract: Provided is a displacement detection device which can uniquely determine displacement of a detection target from output values based on detection as well as make a displacement range of the detection target wider than a displacement range detectable by a sensor. A displacement detection device includes a magnet which is displaced in a displacement direction Ds, is rod-shaped and has a form in which a longitudinal direction and the displacement direction Ds form a predetermined angle ?, and a sensor IC which detects a magnetic flux density of a magnetic field formed by the magnet in an x direction and a z direction orthogonal to the displacement direction Ds and outputs a signal proportional to the magnetic field detected.

Abstract: Provided are a displacement detection device and a continuously variable transmission which directly detect a position of a movable sheave. An infinitely variable transmission includes: a magnet; a movable sheave which has a concave portion on a circumferential surface; and a sensor provided with Hall elements which are arranged between the magnet and the circumferential surface of the movable sheave, detect, in a rotation direction and a direction orthogonal to the rotation direction, each of changes in magnetic flux densities accompanying the displacement of the movable sheave in the magnetic field which is formed by the magnet and attracted to the concave portion, and output output values according to the magnetic flux densities.

Abstract: To provide a displacement detection device that detects a displacement of a measuring object housed in a casing without changing the design of the casing or while suppressing the design change of the casing. A displacement detection device includes a pair of magnets arranged outside an injector body housing a needle with a space between the magnets and forming a magnetic field in the space, a soft magnetic material connected to the needle inside the injector body and displaced in accordance with the displacement of the needle and disposed in the magnetic field formed by the pair of magnets, and a sensor disposed outside the injector body and in the magnetic field formed by the pair of magnets, and detecting a change in magnetic flux density in accordance with the displacement of the soft magnetic material.