Nippondenso Co., Ltd.

Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Nippondenco Co., Ltd.

Toshitaka Yamada

Tiaki Mizuno

Susumu Akiyama

Masumi Kinugawa

Katsunori Ito

Tomoaki Abe

Atsushi Suzuki

Yoshihisa Sato

Masahito Imai

Hirohito Shioya

Akira Tai

Inao Toyoda

Motomi Iyoda

Makiko Sugiura

Hiroshi Okada

Tsuyoshi Fukada

Takamichi Nakase

Norio Omori

Seiki Aoyama

Yoshimi Yoshino

Hirofumi Uenoyama

Hiromi Ariyoshi

Hideya Fujisawa

Katsuhiro Ina

Hiroshige Sugito

Masahito Muto

Yoshinori Fujihashi

Masashi Echigo

Kengo Sugiura

Toshihiro Saga

Takushi Maeda

Hisakazu Koketsu

Haruyuki Ikeo

Hirohito Sioya

Masahiko Kitano

Yoshitaka Nagayama

A motor-assisted turbocharger is composed of a turbine driven by energy of exhaust gas, a compressor rotated by the turbine and a rotary electric machine for assisting rotation of the compressor. The turbine, the compressor and the rotary electric machine are connected to each other by a common rotating shaft. A polygon nut having magnetic member facing fixed magnetic sensor is connected to an axial end of the rotating shaft. A magnetic field formed between the magnetic member and the magnetic sensor changes according to rotation of the rotating shaft. A rotational speed and a rotational position (or angle) of the compressor are detected based on the changes in the magnetic field. Operation of the turbocharger is electronically controlled based on the detected rotational speed and the rotational position.

Rotational speed and position detector for supercharger

A magnetoresistance element detects an angular position of a toothed gear rotated by an engine. The element (first element) is positioned at a vicinity of the peripheral edge of the gear tooth in a magnetic filed supplied from a bias magnet. The magnetic field direction is changed by the tooth, which is detected by the element even when the gear is not rotated before the engine starts. To detect an exact angle of the gear, an additional magnetoresistance element positioned perpendicularly to the first element may be used. The gear tooth position is detected by the first element even when the gear is not rotated, and once the gear rotates, the second element detects an exact angular position of the gear.

Rotation detector using magnetoresistance element positioned in vicinity

A surge protective device, which has a favorable surge-absorbing characteristic while avoiding increase in chip area and in process complexity, is disclosed. In a surge protective device having an ordinary planar bipolar transistor structure and having a voltage-regulation diode to absorb surge current by breakdown of a junction between an emitter region and base region thereof, a surface collector region thereof is shorted to the base region. Accordingly, when surge current is increased, a pn junction between a collector region and the base region is sufficiently forward biased, and thereby a backward transistor is formed. Surge current is sufficiently absorbed by the operation of the backward transistor.

Surge protective device having a surface collector region directly

The output of a filter circuit utilizing a capacitance amplifier circuit is sufficiently stabilized in its temperature characteristics to improve the operational reliability of the circuit. There is provided a DC cutoff filter circuit utilizing a CR circuit constituted by a composite capacitance formed by a capacitance amplifier circuit utilizing an operational amplifier and a series resistor which is grounded to a reference voltage. The reference voltage is a divided voltage output by a voltage follower constituted by an operational amplifier and serves as a virtual ground. Resistors having different temperature coefficients are used. In response to a positive or negative change in the temperature coefficient of the composite capacitance, the reference potential selects the temperature coefficient of the resistors so that the temperature characteristics including those of the amplifier will provide a temperature coefficient which is the reverse of that of the capacitance amplifier circuit, thereby compensating for fluctuation associated with the temperature coefficient of the composite capacitance.

Temperature drift stabilized filter circuit

A semiconductor accelerometer which can satisfy the requirements of both the sensitivity and the fracture strength without any contrivance for providing viscous liquid and beam stopper material is provided. A casing comprises a stem and a shell. The casing houses an accelerometer chip. The silicon accelerometer chip is of double cantilever beam structure. Each beam is provided with piezo resistance layers. The motion of the beams due to the action of acceleration is converted into electrical signals. The resonant frequency of the beams of the accelerometer chip is above the resonant frequency of the casing itself, so that the acceleration components above this resonant frequency are damped by the casing and therefore most acceleration components in the resonant frequency of the beam are damped. As a result, the beams of the accelerometer chip can be protected from the impacts due to the dropping of the accelerometer, or the like.

Semiconductor accelerometer with damperless structure

In fixing a sensor element for sensing stress on a substrate by using an adhesive for semiconductors, the present invention aims to solve both the problems of stress applied from the substrate side due to temperature change and defects in wire bonding in the wire bonding process. In a semiconductor device equipped with a sensor element for sensing stress fixed on a substrate, an adhesive for semiconductors is used which is prepared by compounding resin beads made of resin with a base adhesive made of flexible resin.

Semiconductor device for sensing strain on a substrate

A semiconductor strain sensor includes a base, a peripheral section, a central section and a flexible beam. The peripheral section is bent to the base. Bonding strain is generated at a bonding portion between the base and the peripheral section. The central section extends from the peripheral section. The flexible beam extends from the central section and includes a strain detecting element. The strain detecting element changes its electric characteristic when strain is applied thereto. A thickness of the flexible beam is thinner than that of the central section. The bonding strain is transmitted from the bonding portion to the strain detecting element through a transmission path. The transmission path is bent. The bonding strain is attenuated because it is dispersed at a bending portion of the transmission path. The sensor accurately detects the strain to be detected without a bad influence of the bonding strain.

Semiconductor strain sensor having improved resistance to bonding strain

When an acceleration sensor is used, it is attached to a measured object to detect an acceleration applied to the object. The acceleration sensor includes a package having at least one chamber. A sensor element is disposed in the chamber and has a portion which vibrates in response to the acceleration. Damping liquid is sealed within the package and has a quantity which allows the sensor element to be submerged in the damping liquid and which allows a predetermined quantity of gas to remain in the package. The gas absorbs a thermally-induced volume change of the damping liquid. In the absence of the acceleration, a gas bubble is prevented from separating from the gas. In addition, the gas bubble is prevented from staying in the chamber.

Acceleration sensor

A semiconductor accelerometer includes a package containing damping liquid. A base is fixedly disposed within the package. A semiconductor plate is disposed within the package and is supported on the base. The semiconductor plate has a movable free end and a deformable diaphragm. A semiconductor strain gauge is associated with the diaphragm and deforms in accordance with deformation of the diaphragm. The base has a first surface opposing the semiconductor plate free end. The first surface of the base has a recess for limiting movement of the semiconductor plate free end. The recess extends to and opens at a second surface of the base which differs from the first surface.

Semiconductor accelerometer

A control system for an engine has a temperature sensitive element as part of a device for measuring the air flow in an air intake manifold to the engine. Further, a first pulse signal is generated, corresponding to the rotation of the engine, for controlling the setting of a flip-flop. A transistor is conducted in the set state of the flip-flop to supply a heating electric current to the element. The element supplied with the current is raised to the temperature that corresponds to the air flow in the manifold. When the temperature of the element is raised until the specified temperature difference to the air temperature (measured by a sub temperature sensitive element) is set, the temperature difference is detected by a comparator, and the flip-flop is reset by the detection signal. A pulse-shaped signal corresponding to the set state of the flip-flop is produced as a measurement output signal, supplied as one detection signal of the operating state of the engine to an engine control unit, and the current to the element is controlled to be supplied by the pulse-shaped signal.

Control system for an engine having an air intake passage

In an apparatus for controlling an engine, as an air flow sensor for measuring intake air flow quantity, a heater resistor having temperature-resistance characteristic and a temperature sensitive resistor for sensing air temperature are provided in an intake passage, and heating electric power is supplied to the heater resistor in response to a start signal generated periodically. The heating electric power is cut off when the temperature of the heater resistor is raised to a specified reference temperature predetermined in accordance with the air temperature, so that an output signal indicative of the time width in which the heating electric power is supplied is applied to an electronic control unit to measure air flow quantity therefrom. Further, compensation coefficient stored in a memory is derived in correspondence to the intake air temperature sensed by the temperature sensitive resistor, and the output signal is compensated for by the compensation coefficient to compensate the measured air flow quantity. Based on the compensated air flow quantity, fuel injection quantity, ignition timing or the like is computed in the electronic control unit.

Apparatus for controlling engine

A heater, which comprises an element whose resistance varies with changes in temperature, and a temperature element are provided in the air intake pipe of an engine. This heater and temperature element together with resistors form a bridge circuit to which heating power is supplied via a transistor. An engine control unit generates start signals Tin simultaneously with the rotation of the engine. A flip-flop circuit is set by these start signals and, when set, the transistor is turned on and the heating power rises. The output signal from the bridge circuit is supplied to a comparator and the output signal of the comparator resets the flip-flop circuit, which outputs a pulse-shaped signal representing the airflow quantity as a length of time. This pulse-shaped time signal is sent via a constant current circuit to another comparator, where it is compared with a reference voltage and the output signal from the comparator is supplied together with the above time signal to an exclusive OR circuit. This exclusive OR circuit outputs a first and second pulse signal as the measurement output signal Tout synchronously with the rise and fall of the time signal and this signal is supplied to the engine control unit.

Heat-wire type airflow quantity measuring apparatus

A heat generating element having a thermal characteristic such that its resistance varies in response to changes in temperature is provided in the intake pipe of an engine. A heating power, the voltage of which is set by a reference voltage source, is supplied to the heat generating element via a transistor. The supply of this heating power is controlled by a start pulse signal periodically generated by a set flip-flop circuit when the ignition switch is on. When the heat generating element reaches a predetermined temperature, the supply is cut off by the flip-flop circuit. A measurement signal having a pulse width corresponding to the time period of heating power supply is generated from the flip-flop circuit. The opening of the ignition switch is detected and a one-shot multivibrator is driven to produce a burn-off signal having a pulse width to which the burn-off period corresponds. This burn-off control signal turns the transistor on and heating power is supplied to the heat generating element and the voltage of the reference power source is reduced so that the voltage of the heating power is switched to a low level.

Heat-wire type air flow measurement apparatus

An air flowrate measuring apparatus with a heat wire measures the flow rate of the air flowing through the intake pipe of an engine. The apparatus has a temperature sensitive element which has a specific temperature-resistance characteristic and is disposed in the intake pipe. Constant heating voltage is applied to this element in response to a start signal, thus heating the element. When the temperature of the element rises to a specified value, the application of the voltage is stopped. At the same time, a pulse signal whose width corresponds to the period of applying the voltage is generated. The signal is supplied to an interface circuit through a drive circuit driven by a reference voltage which has been also used to control the heating voltage. The interface circuit comprises two wave-shaping circuits. The first wave-shaping circuit has a filter means of a small integration time constant. The second wave-shaping circuit has a filter means whose integration time constant is large enough to remove noise from the input signal.

Heat wire type air flowrate measuring apparatus

An ignition timing adjusting system for an internal combustion engine wherein the output of a magneto-type generator driven by the engine is used as a power source to generate a constant voltage output through a voltage regulator circuit, and a rotational angular position of the engine is detected by a sensor and the corresponding output signal being used as a reference signal in order to electronically determine an ignition timing by an advance angle computing circuit energized by the constant voltage output of the voltage regulator circuit, and further detecting the constant voltage output of the regulator circuit, and an advance angle adjusting circuit cancels the computed output from the advance angle adjusting circuit when the detected voltage is less than a voltage which is an absolute minimum voltage necessary for the accurate ignition timing operation, whereby when the detected constant voltage output is not adequately regulated the computed output of the advance angle adjusting circuit causing the excessively advanced ignition timing is ignored, instead, forcibly timing the ignition to occur at the low-speed fixed angular position.

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Nagoya, Japan

Toshitaka Yamada