Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Subaru Corporation

Nidec Tosok Corporation

Naoki Hiraoka

Izuru Shinjo

Wataru Fukui

Yutaka Ohashi

Masahiro Yokotani

Noriaki Hayashi

Yasuyoshi Hatazawa

Hiroshi Sakanoue

Hideki Umemoto

Kazuhiko Tsutsumi

Tatsuya Fukami

Motohisa Taguchi

Yuuichi Sakai

Yuji Kawano

Takuji Nada

Shunichi Wada

Tomohiro Yasuda

Takashi Asai

Shigeki Tsujii

Tomoya Ozawa

Daisuke Murata

Naohiro Mishiro

Keita Kobayashi

Kenro Takahashi

A vehicle cooling system includes a circulation flow path section which has a first flow path section and a second flow path section, and a solenoid valve which can switch between an open state in which the first flow path section and the second flow path section are connected and a closed state in which the first flow path section and the second flow path section are blocked. The circulation flow path section includes a valve body accommodating section configured to include a first accommodating section and a second accommodating section which connects the first flow path section and the second flow path section in the open state, and a connection flow path section whose one end is connected to the first flow path section. The other end of the connection flow path section opens to the first accommodating section.

Vehicle cooling system

The magnetic sensor in the invention is arranged to detect a change of magnetic field caused by a movement of the magnetic movable by a magnetic sensor element arranged with a gap to the magnetic movable, to convert the detected change of magnetic field by first and second bridge circuits into electric signals, to generate first and second rectangular-wave signals by first and second comparator circuits depending upon the electric signals, and to form a signal having at least four levels by a signal forming circuit, thereby detecting a moving direction of the magnetic movable depending upon a level-change order in the signal. This makes it possible to detect a rotating direction of the magnetic movable rapidly and correctly.

Magnetic sensor

A magnetic detector, wherein the magnetic/electric conversion element is constituted by at least six segments symmetrically arranged in a direction in which the magnetic moving body rotates maintaining a predetermined pitch with respect to the center line of the magnet, first and second bridge circuits are constituted so as to produce outputs accompanying the rotation of the magnetic moving body, and a third bridge circuit is constituted so as to produce an output accompanying the rotation of the magnetic moving body, and wherein a comparison level of a comparator circuit that shapes the waveform of a differential output signal of the first and second bridge circuits is adjusted relying upon an output signal of the third bridge circuit.

Magnetic detector maintaining high detection precision without affected by the temperature characteristics of the sensing element

The magnetic sensor in the invention includes a detecting section that detects a change of magnetic flux due to a movement of the magnetic movable, comparator circuits constituting a converting section that converts a change of magnetic flux detected by the detecting section into an electric amount, and a D-FF circuit device, in a sensor unit having a power-supplying power terminal VB, a ground terminal GND and an output terminal VOUT. A current control section is provided to change the amount of current flowing through at least one of the power terminal and the ground terminal, correspondingly to a moving direction of the magnetic movable. Thus, a moving direction of the magnetic movable can be determined depending upon the amount of current.

A magnetic detection apparatus is able to make a selection between AC coupling and DC coupling thereby to improve the accuracy of a final output signal corresponding to a magnetic movable element, thus making it possible to ensure excellent detection performance. The magnetic detection apparatus with a sensor composed of magnetoresistive elements () for detecting the strength of a magnetic field includes a first comparison circuit () that has a first comparison level (VR), and waveform shapes the amplitude of a detection signal (C) from the magnetoresistive elements () through DC coupling, a second comparison circuit () that has a second comparison level (VR), and waveform shapes the amplitude of the detection signal C through DC coupling, and a third comparison circuit () that has a third comparison level VR, and waveform shapes the amplitude of the detection signal C after AC coupling.

Magnetic detection apparatus

A magnetic detection apparatus includes a first block, a second block, and an exterior resin covering the first block and the second block. The first block includes a magnetoresistive element for detecting a change in a magnetic field that varies in accordance with movement of a rotating member, electronic components forming a protection circuit against external noise, a first lead frame electrically connected with the electronic components, and a first base in which the electronic components, the first lead frame and the magnetoresistive element are sealed with a resin. The second block includes a magnet arranged in opposition to an object to be detected for generating a magnetic field, a second lead frame electrically connected with the first lead frame and having a connector terminal for outputting an output signal of the magnetoresistive element to an external member, and a second base in which the second lead frame is sealed with a resin.

A magnetic detection apparatus can accurately detect the rotational position of a magnetic moving member even when intervals between adjacent teeth formed thereon and the circumferential width of each tooth itself are both small and when an opposing distance between the magnetic moving member and first and second magnetoresistive segments is large. A processing circuit is arranged apart from the magnetic moving member on a plane thereof, which is formed on its periphery with the teeth. The processing circuit has a bridge circuit including the first magnetoresistive segment and the second magnetoresistive segment. A magnet applies a magnetic field to the first and second magnetoresistive segments, and to the magnetic moving member in a direction of an axis of rotation thereof. The second magnetoelectric conversion element is arranged substantially on a center line passing through the center of the magnet on a line in opposition to the magnetic moving member when viewed along the direction of the axis of rotation of the magnetic moving member, so that a differential output can be obtained from the outputs of the first magnetoelectric conversion element and the second magnetoelectric conversion element.

Six magneto-resistance segments are formed by film-forming on a signal processing circuit part consisting of an IC chip and are disposed in a predetermined rotation direction of a magnetic moving body, symmetrically about the centerline of a magnet perpendicular to that rotation direction. Two pairs of magneto-resistance segments, whose pitch centers are positioned symmetrically with respect to the centerline of the magnet, form first and second bridge circuits, and the remaining pair of magneto-resistance segments, which has its pitch center on the centerline of the magnet, forms a third bridge circuit.

Rotation detecting device

A magnetic field sensing element comprises an underlayer formed on a substrate, a giant magnetoresistance element formed on the underlayer for detecting a change in a magnetic field, and an integrated circuit formed on the substrate for carrying out predetermined arithmetic processing based on a change in a magnetic field detected by the giant magnetoresistance element, wherein the giant magnetoresistance element and the integrated circuit are formed on the same surface.

Magnetic field sensing element and device having magnetoresistance element and integrated circuit formed on the same substrate

Magnetic detection device for detecting moving direction of a toothed magnetic movable body

A method of manufacturing a rotation sensor is provided. In the method, an insert conductor having a predetermined shape and having at least a connector terminal and a conversion device terminal is provided. The insert conductor is insert-molded in a resin base such that at least the connector terminal and the conversion device terminal of the insert conductor remain exposed from the resin base. A resin connector part is molded such that the resin connector part encircles the connector terminal. Also, a magnetoelectric conversion device is connected to the conversion device terminal of the insert conductor, and positioning parts are provided at a tip of the resin base. In addition, the magnetoelectric conversion device is sandwiched between the positioning parts to securely hold the magnetoelectric conversion device, and a press fit part is formed at the tip of the resin base. Also, an output terminal of the magnetoelectric conversion device is pressed against the conversion device terminal of the insert conductor with the press fit part.

Manufacturing method of a rotation sensor

The invention provides a magnetic object motion sensor which can operate with high accuracy not only when a magnetic object moves at high speeds but also even when it moves at low speeds, which can be produced with a greater production tolerance and a greater dimensional tolerance. The magnetic object motion sensor includes: magnetoelectric transducer elements disposed opposite protrusions of a moving magnetic object; a magnet for generating bias magnetic flux toward the magnetoelectric transducer elements; unbalanced bias producing means for producing imbalance in the magnetic field sensitivity between the magnetoelectric transducer elements; a differential amplifier for amplifying in a differential fashion the electric signals output by the magnetoelectric transducer elements; a waveform shaping circuit for converting the differential signal output by the differential amplifier to a pulse signal corresponding to the edges of the magnetic material protrusion; the unbalanced bias producing means producing a difference in the amplitude of the magnetic flux density between that applied to one element of the pair of magnetoelectric transducer elements and that applied to the other element so that the difference in the electric signal level corresponding to the difference in the amplitude of the magnetic flux density becomes greater than the hysteresis of the waveform shaping circuit, thereby, in effect, introducing imbalance in the sensitivity between the magnetoelectric transducer elements.

Rotating magnetic object motion sensor with unbalanced bias

A magnetic detector having high productivity is provided by producing a connector and a base as separate units, electrically interconnecting them, forming a cut-out portion in a press-in portion of the base, and injecting a thermosetting resin adhesive into a whole case. The case also has a recess portion that prevents excess injected resin from leaking to the outside of the case. The structure of the base also allows for easier injection of resin and simplified connection of the magnetic resistance element to the base.

Magnetic detector having separate base and connector units and production process therefor

A magnetic field sensing element comprises an underlayer formed on a substrate, a giant magnetic resistance element formed on the underlayer for detecting a change in a magnetic field, and an integrated circuit formed on the substrate for carrying out predetermined arithmetic processing based on a change in a magnetic field detected by the giant magnetic resistance element, wherein the giant magnetic resistance element and the integrated circuit are formed on the same surface.

Growing community of inventors

Tokyo, Japan

Naoki Hiraoka