Mazda Motor Corporation

Toyo Kogyo Co., Ltd.

Mitsubishi Denki Kabushiki Kaisha

Masahiko Matsuura

Haruo Okimoto

Kazuhiko Ueda

Yasuyuki Morita

Katsuhiko Yokooku

Hideo Shiraishi

Sadashichi Yoshioka

Nobuo Doi

Kazumichi Tsutsumi

Tadashi Kaneko

Makoto Hotate

Tadayoshi Kaide

An engine control system having an engine vibration sensor which detects engine vibrations. A control circuit is provided for discriminating engine roughness wherein the engine vibration level is above a predetermined level and for decreasing the fuel supply continuously when engine roughness is not detected, in order to make the mixture leaner, but increasing the fuel supply when engine roughness is detected to make the mixture richer. A detector is provided for detecting a specific engine condition wherein the mixture is enriched for specific purposes. The control circuit is responsive to the output of the engine condition detector and discontinues the roughness control when the specific engine condition is detected.

Engine roughness control

A control system for a vehicle engine in which fuel supply quantity is controlled in accordance with the engine roughness level. An engine roughness sensor is provided for detecting engine vibrations and producing a roughness signal which is compared with a reference signal. When the roughness signal is greater than the reference signal, the fuel supply is increased to enrich the air-fuel mixture but, when the roughness signal is smaller than the reference signal, the fuel supply is decreased to make the mixture leaner. The reference signal is smallest in idling operation and stepwisely increased depending on an increase in the load on the engine.

Engine roughness control means

An engine air-fuel ratio control system in which the engine operating range is divided into a light load, medium load and heavy load regions. In the light load region, a control of the fuel supply is made so as to provide a mixture of leaner than the stoichiometric value. In the medium load region, a feedback control is made based on the signal from an O.sub.2 sensor and, in the heavy load region, a control is made to provide a richer mixture. In the transient between the light load and medium load regions, the air-fuel ratio is changed with a rate which changes in accordance with the rate of change in the engine load.

Air-fuel ratio control for an international combustion engine

A throttle opening control device includes a driver for controlling the opening of the throttle during idling and a judgment circuit or an idle switch for determining an idling condition and means for halting driver operation during non-idling intervals. In one embodiment, a sensor detects the throttle opening and supplies the same to a throttle driver by way of a difference circuit which forms a deviation value between the output of the sensor and that of an arithmetic unit whose operation is suspended during non-idling periods.

Control device for internal combustion engine

Engine cooling system including a cooling water passage having cooling water jackets formed in the engine and a water pump for circulating cooling water through the water passage. A driving motor is provided for driving the water pump and a control circuit for the motor receives an engine speed signal so that the speed of the water pump is decreased to a predetermined low level when the engine temperature is low so that the engine can be warmed up rapidly while maintaining a cooling water circulation for preventing local overheating of the engine.

Cooling system for liquid-cooled internal combustion engines

Engine cooling system including cooling water passages having cooling water jackets formed respectively in the hot temperature portion and the cold temperature portion of the engine and water pumps for circulating cooling water through the water passages. Driving motors are provided for driving the water pumps and a control circuit for the motors receives an engine speed signal so that the water pump for the water passage to the cold temperature portion of the engine is stopped when the engine temperature is low so that the engine can be warmed up rapidly while maintaining a cooling water circulation through the water passage in the hot temperature portion for preventing local overheating of the engine.

Growing community of inventors

Hiroshima, Japan

Masahiko Matsuura