Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Tetsuya Kaneko

Kenji Nishida

Tomiyuki Sasaki

Naoki Sakamoto

Seiji Hatcho

Shinichi Wagatsuma

Kazuto Fukuzawa

Ryosuke Ibata

Akira Kato

Hiroshi Kitagawa

Koji Aoki

Kenichiro Nakamura

Yoichi Iwata

Toshiaki Hirota

Jun Takahashi

Tetsu Teshirogi

Hiroshi Ito

Tsuyoshi Takizawa

Satoshi Honma

Kenjiro Saito

Ranju Imao

Masami Watanabe

Takahiro Kitamura

Daiji Kawaguchi

Hirotaka Sato

Shunji Akamatsu

Yuki Takano

A diagnosis apparatus of a fuel supply system includes an operation state detector, an air-fuel ratio sensor, a fuel injection amount calculator, a threshold value table, an abnormality information acquiring device, and an abnormality determining device. In the threshold value table, operation ranges of an internal combustion engine are provided based on an engine speed and a throttle opening. In the threshold value table, a lean side threshold value and a rich side threshold value of an air-fuel ratio correction factor to determine abnormality of the fuel supply system are set beforehand for each of the operation ranges. The abnormality information acquiring device is configured to determine whether the air-fuel ratio correction factor has exceeded the lean side threshold value or the rich side threshold value extracted from the threshold value table according to an operation state so as to acquire abnormality information.

Diagnosis device for fuel supply system

In an exhaust-gas-purification catalytic heating device that houses a current heater in a conductive metallic housing where a catalytic unit is housed, the current heater being arranged at an upstream side of the catalytic unit along a distribution direction of exhaust gas, the current heater has a negative electrode directly coupled to the housing electrically coupled to an external ground wire, the current heater has a positive electrode with which a rod-shaped terminal is continuous, the terminal passing through the housing in an electrically insulating state so as to be electrically coupled to a power line outside the housing, and the terminal has a portion protruding from the housing, the protruding portion being covered with a terminal cover.

Exhaust-gas-purification catalytic heating device

In an alcohol concentration estimation apparatus for an engine, a first crank angular speed (&#x3c9;) within a first predetermined interval overlapping with the compression top dead center is calculated, and a first variation amount (&#x394;&#x3c9;) is calculated by subtracting &#x3c9;from an average engine speed. A second crank angular speed (&#x3c9;) within a second predetermined interval overlapping with the combustion bottom dead center is calculated, and a second variation amount (&#x394;&#x3c9;) is calculated by subtracting &#x3c9;from &#x3c9;. In a relationship between air fuel ratio A/F and an indicated mean effective pressure (IMEP)/charging efficiency (&#x3b7;c) of the engine when the engine is operated with a predetermined fuel injection map indicating a relationship between A/F and IMEP/&#x3b7;c for each desired alcohol concentration, IMEP/&#x3b7;c is substituted by &#x394;&#x3c9;ratio to estimate an alcohol concentration in fuel. The alcohol concentration estimation apparatus eliminates requirement of sensors for detecting an intake air mass.

Alcohol concentration estimation and detection apparatus for an engine

To prevent a reduction in engine load detection accuracy due to variations in reluctor size within mass production tolerances, an engine control unit includes a pulse generator PC that detects a reluctor to output crank pulses. An angular velocity calculating unit calculates a first crank angular velocity on the basis of an interval between two crank pulses output in a predetermined section near compression top dead center TDC, and detects near overlap top dead center OLP the same reluctor used for calculating the first crank angular velocity to calculate a second crank angular velocity on the basis of an interval between generated two crank pulses. An engine load estimating unit calculates, as an engine load, a difference between the first crank angular velocity and the second crank angular velocity. The engine load is indicated mean effective pressure over a whole cycle including negative work done by the engine.

Engine control unit

An ignition timing setting apparatus includes a pulse generator for generating crank pulses corresponding to crank angles, a crank angular speed variation calculating section for calculating a crank angular speed variation based on an interval of the crank pulses, an engine load estimating section for estimating an indicated mean effective pressure from the crank angular speed variation, and an ignition timing determining section having an ignition timing control map for determining an ignition timing advance quantity in accordance with the estimated indicated mean effective pressure and an engine temperature or an engine speed. Such ignition timing setting apparatus sets appropriate ignition timings for avoiding a knocking occurrence load range based on an accurate estimated engine load.

Engine ignition timing setting apparatus

An air-fuel ratio estimating device can include an amount of fuel injected calculating unit which can estimate the amount of fuel injected GF for each cycle on the basis of a driving time Tout of a fuel injection valve. A proportional constant calculating section determines a proportional constant K, using the estimated charging efficiency CE and the amount of fuel injected Gf, when the output value of a sensor is in a transition region R. When the sensor output value is not in the transition region R, an air-fuel ratio A/F is estimated from the determined proportional constant K, a charging efficiency CE calculated by a calculating section, and the amount of fuel injected Gf.

Air-fuel ratio estimating/detecting device

An air-fuel ratio control system for an internal combustion engine has a catalytic converter arranged in an exhaust passage. A maximum oxygen storage amount indicative of the maximum amount of oxygen that can be stored in the catalytic converter is calculated. The air-fuel ratio of a mixture supplied to the engine is forcibly oscillated at a predetermined frequency and a predetermined amplitude. At least one of the predetermined frequency and the predetermined amplitude is changed at a predetermined rate of change. A predetermined rate of change of the at least one of the predetermined frequency and the predetermined amplitude is set in dependence on the maximum oxygen storage amount to thereby secure the maximum purification rate of the catalytic converter.

Air-fuel ratio control system for internal combustion engines and

An air-fuel ratio control system for an internal combustion engine having a catalyst arranged in the exhaust system, for purifying exhaust gases emitted from the engine. Upstream and downstream air-fuel ratio sensors arranged in the exhaust system at respective locations upstream and downstream of the catalyst detect the concentration of a specific component present in the exhaust gases. An ECU controls the air-fuel ratio of an air-fuel mixture supplied to the engine, in response to the outputs from the upstream and downstream air-fuel ratio sensors. The ECU detects deterioration of the catalyst caused by sulfur poisoning, based on at least the output from the downstream air-fuel ratio sensor.

Air-fuel ratio control system for internal combustion engines

Growing community of inventors

Wako, Japan

Tetsuya Kaneko