Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Kouzou Katogi

Minoru Ohsuga

Shinji Nakagawa

Seiji Suda

Takanobu Ichihara

Hirohisa Yamamura

Osamu Igarashi

Kazuhiko Kanetoshi

Keiichi Tokuyama

Yutaka Takaku

Hiroaki Hoshika

Masaru Kugo

Hideyuki Ouchi

An EGR flow rate control apparatus of an internal combustion engine is provided that can correct with high accuracy an EGR gas flow rate measured by a gas flow rate measurement apparatus in an EGR passage and control with high accuracy a gas flow rate regulating valve to reduce discharge amounts of PM and NOx in exhaust gases. An EGR flow rate control apparatusof an internal combustion engine includes a gas flow rate correction unitthat corrects the EGR gas flow rate based on a first operating state parameter relating to pressure fluctuations of the intake pipe or exhaust pipe of the internal combustion engine and a second operating state parameter relating to a flow channel resistance of the EGR flow channel.

EGR flow rate control apparatus of internal combustion engine

The present invention performs correction appropriately according to errors in the fuel system and air system respectively and corrects both variations in the air-fuel ratio and torque. When the difference between a target air-fuel ratio and a real air-fuel ratio is equal to or below a predetermined value when feedback control based on the air-fuel ratio of an exhaust manifoldA is in progress, the air-fuel ratio of a cylinder cylhaving the largest variation of angular acceleration is corrected to the rich side, for example, by increasing the amount of fuel. Angular acceleration per cylinder is then detected again and when the variation in angular acceleration among cylinders is not eliminated, it is judged that there is an error in the amount of air control of the cylinder having the largest variation and the amount of air, amount of fuel, ignition timing or the like are corrected.

Engine control apparatus

There is disclosed an apparatus in which changes of linear A/F sensor or engine response characteristics can be detected with high precision in a broad range during operation of an engine. The apparatus includes a controller for controlling an air/fuel ratio of each cylinder of a multiple cylinder engine, and a linear A/F sensor for emitting an output which is proportional to the air/fuel ratio of an exhaust tube assembly. The air/fuel ratio of a specific cylinder is changed by a predetermined amount, a vibration component amplitude or a frequency component based on an engine rotation number is extracted from a signal obtained from the linear A/F sensor , and the response characteristics of an air/fuel ratio detector or the engine are detected from the amplitude or a power of the frequency component.

Engine self-diagnosis apparatus and control apparatus

In a color liquid crystal type electronic instrument panel, the quantity of light to be radiated from a background light source is changed in accordance with a color to be displayed. The color liquid crystal type electronic instrument panel is of the type that a plurality of plural-primary-color stripe filters are disposed on each segment of a display element in the longitudinal direction of the segment; a voltage is applied to electrodes corresponding to the stripe filters having a color selected based on the contents to be displayed, and the background light source is positioned at the back of the display element to enable color-displaying. A device for detecting the brightness of outdoor light is further provided in the liquid crystal display type electronic instrument panel, wherein the quantity of light to be radiated from the background light source is changed in accordance with a detected signal by the detecting device.

Electronic instrument panel

In a segment display type multi-color liquid crystal display device, the area of the display surface of the display device except the areas of segment electrodes is formed so as to present a color identical or similar to a color presented by the segment electrodes in an unselected state. Selected segments can be clearly recognized.

Liquid crystal display device

Growing community of inventors

Hitachi, Japan

Kouzou Katogi