Hitachi, Ltd.

Toru Sugawara

Matsuo Amano

Shinichi Sakamoto

Seiko Suzuki

Masumi Imai

Sigeyuki Kobori

Takao Sasayama

Noriyuki Kinjo

Masayuki Miki

Kanji Kawakami

Yoshikazu Hoshi

Yasunori Mouri

Toshio Furuhashi

Shigeki Tsuchitani

Satoshi Suzuki

Shuichi Ohara

Isamu Komatsu

Masahiro Takasaka

Tsukasa Yamauchi

Yoshikazu Aochi

Toru Takahasi

A method of electronically controlling the operation of an internal combustion engine is effected on the basis of results of arithmetic operations of digital control quantities derived from detected operating conditions of the engine through digital processing operations. The digital processing operations are subdivided into a number of tasks in dependence on the control functions to be performed. In addition, these tasks are subdivided into a plurality of priority levels. The memory has a task control block having run or execution flag areas in response to the priority levels and start request flag areas in response to the tasks, the start request flag areas being classified in accordance with the levels, in order to make it easy to correct, alter or add tasks. An order for starting the execution of the task is always controlled in accordance with the condition of the run flags and the start request flags.

Engine control method

The invention relates to a humidity sensor of electric resistance type whose electric resistance changes in accordance with an ambient humidity, characterized by a protective film of silicone resin provided on the surface of a humidity-sensitive material, and to a method for preparing the same. The protective film of silicone resin is formed by applying a varnish of siloxanes to the humidity-sensitive material and subjecting the varnish to reaction. The varnish can be of one-part curing system or two-part curing system, and desirably the reaction of siloxanes is a cross-linking reaction. The formed protective film is not influenced by swelling or shrinking of the humidity-sensitive material, and is prevented from flowing off due to a temperature rise, or from deposition of dusts, etc.

Humidity sensor with improved protective layering

A method of starting the operation of an internal combustion engine utilizes a turning force transmitted from wheels of a vehicle through a clutch in addition to a driving force generated by a starting motor. A computer for controlling engine operations detects the initiation of the engine starting operation on the basis of the rotating speed of the engine or intake air quantity and additionally detects the termination of the engine starting operation when the engine rotating speed or intake air quantity exceeds an associated reference value. When the engine stops in the course of running of a vehicle, the engine can be re-started under the influence of the inertial force of the vehicle without resorting to the operation of the starting motor.

Method for starting the operation of an internal combustion engine

A method of controlling, electronically, the operation of an internal combustion engine on the basis of results of arithmetic operations of digital control quantities derived from detected operating conditions of the engine through digital processing operations. The digital processing operations are divided into a number of tasks in dependence on the control functions to be performed. The method comprises a step of setting an activation request indication for a task through the execution of another task, a step of setting an activation request indication for a task through execution of the task itself, a step of searching the activation request indications for the individual tasks, and a step of executing the tasks to which the activation requests are issued on the basis of the effects of the tasks.

Electronic type engine control method

An electronic fuel feed system wherein pulses generated in synchronism with the revolutions of an engine are multiplied by N, the suction air of the engine is measured by a swirl-type air flow meter, the pulses increased N times as fall within a pulse of the air flow meter are counted, and the quantity of fuel supply is calculated from the inverse number of the count value.

Electronic fuel feed system

A temperature responsive apparatus includes a thermocouple producing a thermoelectric e.m.f. depending on the temperature difference between a temperature to be detected and a circumferential temperature and a first winding supplied with current from the thermocouple to generate a first magnetic field. A second winding is connected to a voltage source to generate a second magnetic field in the opposite direction to that generated by the first winding and a reed switch is positioned in the total magnetic field generated by the first and the second windings so as to respond to the intensity of the total magnetic field to make and break its contacts. A diode is also connected to the voltage source, and the second winding is always excited in accordance with the voltage drop across the diode to maintain said second magnetic field.

Temperature responsive apparatus employing a thermocouple

A solid state relay or controlled switch for connecting an AC power source to a load includes a solid state switching circuit in which a semiconductor controlled rectifier element, such as a photothyristor, thyristor or light-AC controlled element, is ignited by an external control signal, thereby to feed a load with an alternating current. A zero voltage switching circuit which executes switching when the instantaneous value of the amplitude of the supply voltage of the AC load current is zero or a value close thereto is connected to the rectifier element. As an improvement, a series circuit consisting of a resistor and a capacitor are connected between the base and emitter of a transistor in the zero voltage switching circuit. Thus, a zero voltage switching solid state relay whose withstand voltage build-up rate is enhanced and whose switching is endowed with a hysteresis characteristic is provided.

Zero voltage switching solid state relay

A thermal time-delay switch comprises contacts which are normally engaged, a first bimetallic element associated with one of the contacts to separate the contacts from each other with temperature rise in the first bimetallic element, a second bimetallic element associated with the other of the contacts to bring the contacts into engagement with each other with a temperature rise in the second bimetallic element, and a heating resistor provided for each of the first and second bimetallic elements to heat it. The relative displacement between the contacts caused by the first bimetallic element with the temperature rise therein is larger than that caused by the second bimetallic element, so that the contacts are separated from each other substantially independent of voltage fluctuations over a wide range of a voltage source feeding the two heating resistors when the heating resistors have been connected to the voltage source for a given period of time.

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Hitachi, Japan

Toru Sugawara