Canon Denshi Kabushiki Kaisha

Canon Kabushiki Kaisha

Masahiro Kawase

Shinichi Tazaki

Hiroshi Sato

Hitoshi Kaneko

Takahiro Matsuoka

Norihisa Urayama

Takayuki Yagi

Makoto Kameyama

Naoki Saito

Takahiro Nakagawa

Koichi Hara

Naruki Suzuki

Takumi Sato

The inspection device includes: a conveyance route that conveys an inspection object at moving speed v; a first magnetic detector and a second magnetic detector that detect a magnetic field of a magnetic foreign object contained in the inspection object; an amplifying unit that amplifies detection signals of the first magnetic detector and the second magnetic detector; and a computation processing unit that performs processing of multiplying the detection signal of the second magnetic detector by a signal obtained by delaying the detection signal of the first magnetic detector. The first magnetic detector and the second magnetic detector each include one magnetic sensor and the magnetic sensors form a pair.

Inspection device

The present invention provides a triaxial magnetism detecting apparatus having a high mechanical strength and being compact in size by simplifying the arrangement configuration of magnetism detectors for the reduction of the number of components and allowing easy angular adjustment of the magnetism detectors and easy installation of the magnetism detectors on the apparatus body, and a satellite. A triaxial magnetism detecting apparatus has a power supply board, a circuit board, and a magnetism detecting unit, which are fixed on a body, and the circuit board and the magnetism detecting unit are horizontally connected. By using the magnetism detecting unit, the triaxial magnetism detecting apparatus detects magnitudes of magnetic fields in mutually perpendicular X-axis, Y-axis, and Z-axis directions.

Triaxial magnetism detecting apparatus and satellite

When a through hole is formed in a primary conductor, a measurement target current partially becomes a bypass current that flows around the through hole. Only a magnetic field component in the X-axis direction is generated from the current that flows through a portion without the influence of the through hole. However, the bypass current generates a magnetic field component in the Y-axis direction at the tilt portion. A magnetic detection element having a magnetic field detection sensitivity only in the Y-axis direction is installed near the through hole such that the magnetic field detection direction is set in the Y-axis direction, thereby detecting the magnetic field component and measuring the current amount without the influence of a neighboring current.

Method of detecting magnetic field generated from current and estimating current amount

A measurement module includes a pair of input terminals, a pair of current paths connected to the pair of input terminals, and a pair of output terminals. A partition that is a non-magnetic insulating portion partitions an internal space of the measurement module into two spaces. Low-current components such as a magnetic detection element are disposed in a space different from a space in which the pair of current paths are housed. The presence of the partition allows the low-current components and the pair of current paths to be disposed close to one another, thus making it possible to reduce the size of the measurement module.

Measurement module, electronic apparatus, power supply tap, power supply unit, and built-in measurement module

A current sensor does not have large dimensions but is adapted to highly sensitively detect an electric current and can be manufactured with ease at low cost. The current sensor comprises parallel electric wire sections of a pair of electric wires arranged in parallel with each other and adapted to flow respective electric currents of the same intensity in directions opposite to each other and a magnetic detection device arranged on a prolonged line connecting the center axes of the parallel electric wire sections. The magnetic detection device has a magnetic field detecting direction rectangular relative to said prolonged line and is adapted to detect the difference between the magnetic field formed by the parallel electric wire section located close to the magnetic detection device and the magnetic field formed by the parallel electric wire section located remote from the magnetic detection device and directed oppositely relative to the former magnetic field in order to detect the intensity of the electric currents flowing through said parallel electric wire sections.

Current sensor and current detection unit using the same

A magnetic field detection circuit comprises a magnetic impedance device, a detection coil wound around or arranged close to the impedance device, an electric current application circuit for applying a pulse-shaped high frequency electric current substantially equally swinging to the positive side and the negative side to the magnetic impedance device, and a detection circuit for detecting a voltage generated in the detection coil in response to rises and falls of the applied pulse-shaped electric current and outputting a signal corresponding to the intensity of the external magnetic field on the basis of the outcome of the detection. The magnetic field detection circuit can provide nil-point setting on a stable basis by means of a simple circuit arrangement at low cost.

Magnetic field detection circuit using magnetic impedance device

Provided is a rocking member apparatus comprising torsion springs, a rocking member axially supported by the torsion spring, and a supporting substrate, the rocking member being rockable about the torsion spring, wherein a hard magnetic member is provided on one surface of the rocking member, a coil and a soft magnetic member, which are arranged so as to be spaced apart from the rocking member, the coil and the soft magnetic member are arranged at different positions in a direction vertical to the one surface, and the hard magnetic member is arranged at a position which is the same position as the soft magnetic member and the one surface in a direction vertical thereto, or a position which is on the side where the coil is arranged as seen from the soft magnetic member, whereby the apparatus can be made small and lightweight and allows increased deflection angle, high-speed scanning, and reduced power consumption.

Rocking member apparatus

A magnetic detection element suitable for detecting a strength of an external magnetic field, has a magnetic thin film formed on a single non-magnetic substrate, a circuit that applies a high-frequency current to the magnetic thin film, and a spiral-type planar coil that is stacked on the magnetic thin film with an insulating layer, in between. The magnetic thin film is formed in a longitudinal shape, and magnetic anisotropy is provided such that the direction of easy magnetization is orthogonal to the longitudinal direction of the longitudinal shape.

Magnetic detection element utilizing magneto-impedance effect, production method of the element, and portable equipment using the element

An electric current sensor which includes a pair of magnetic detectors arranged near a signal line, flowing through which is an electric current to be detected. Additionally, a differential amplifier is included for differentially amplifying two signals obtained by the paired magnetic detectors, detecting a magnetic field from the electric current flowing through the signal line, and outputting a detection signal for the detected electric current. The paired magnetic detectors are arranged adjacent to each other along a first straight line and sandwiching between them a second straight line. The first straight line is perpendicular to but spaced from the signal line, and the second straight line crosses perpendicularly to both the first straight line and the signal line. The paired magnetic detectors have the same magnetic field detecting direction, which may be parallel or inclined relative to the second straight line.

Electric current sensor

In a magnetic impedance element in which an element body is formed of a magnetic thin film formed on a non-magnetic substrate, and when a high-frequency current is supplied to the magnetic thin film, an impedance between both ends of the magnetic thin film changes in accordance with an external magnetic field, the magnetic thin film is formed in a slender zigzag pattern obtained by folding a straight line in parallel several times, and an easy axis of magnetization of the magnetic thin film is so set as to be directed along the longitudinal direction of the pattern. Also, assuming that a thickness of the magnetic thin film is T, a line width of the pattern is W, and a length of the pattern is L, T is in a range of 1 to 5 &mgr;m, and L/(W&times;T) is in a range of 10 to 400&times;10 m .

Magnetic impedance element having a highly linear magnetic field detection range

A first portion of a perimeter of an outer circumferential portion of a tire is magnetized with a first polarity along the steel belt in one circumferential direction less than 360&deg; and a second portion of the perimeter is magnetized with a second polarity in an opposite circumferential direction. The magnetic field generated by the magnetized steel belt is detected by two magnetic detection elements, which are set so that the magnetic field detection directions of the two magnetic detection elements are parallel to the side surface of the tire, and the two elements are juxtaposed in a direction perpendicular to the side surface of the tire.

Method for detecting the magnetic field of a tire

In a magnetic detecting element utilizing a magnetic impedance effect, a high-permeability magnetic film is formed on a non-magnetic substrate and has magnetic anisotropy in a predetermined direction in the plane of the magnetic film. A high-frequency current is applied across two point in a direction perpendicular to the direction of the magnetic anisotropy, and a change in impedance generated between the two points is converted into an electric signal to obtain an output.

Magnetic detecting element utilizing magnetic impedance effect

A magnetic sensor for detecting magnetic fields deriving from a magnetic body to detect any magnetic body on a non-magnetic body by moving relative to the non-magnetic body in prescribed relative moving directions along the surface of the non-magnetic body includes a magnetizing magnet in which a line connecting the N and S poles thereof is a direction substantially orthogonal to, and of which one pole is arranged either in contact with or in proximity to, the surface of the non-magnetic body; and a magnetism detecting element having two magnetic detectors arranged along a magnetic field detecting direction, the magnetic field detecting direction being orthogonal to the relative moving directions in a surface parallel to the surface of the non-magnetic body, wherein the magnetic body is magnetized by the magnetizing magnet along with the movement relative to the non-magnetic body, and magnetic fields according to the quantity of the magnetized part of the magnetic body are differentially detected by the two magnetic detectors of the magnetism detecting element.

Magnetic sensor having magnetic detectors arranged in a direction orthogonal to a relative moving direction

A tire (,) used includes a steel belt in its outer circumferential portion. A magnetic sensor (,) including a pair of magnetic detection elements (,A,,B), which are arranged so that their magnetic detection directions become parallel to each other or series each other, is set in the vicinity of a rear tire (,) in a trunk room of a vehicle (,). Changes in magnetic field upon revolution of the tire (,) are differentially detected by the magnetic detection elements (,A,,B), and the revolution of the tire (,) is detected on the basis of the differentially detected output waveform. Among a plurality of peaks present in the differentially detected output waveform, a peak, the potential difference from the immediately preceding peak of which is equal to or larger than a predetermined threshold value, is detected as an effective peak, which is effective for tire revolution detection, and the revolution speed of the tire is calculated by detecting the number of effective peaks.

Growing community of inventors

Saitama, Japan

Masahiro Kawase