Nippondenso Co., Ltd.

Aisin Seiki Kabushiki Kaisha

Toyota Jidosha Kogyo Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Aisin Seiki Company, Ltd.

Toyoda Gosei Kabushiki Kaisha

Toyoda Gosei

Toshio Kondo

Akio Kobayashi

Shigenori Isomura

Masayoshi Katagiri

Hiroshi Haraguchi

Yasuo Sagisaka

Masahiko Tajima

Tomomi Eino

Hisashi Iida

Hiroshi Uemura

Yoshiharu Adachi

Akira Masuda

Hideaki Norimatsu

Juichi Shibatani

Katsuhiko Kodama

Fumio Fujimori

Nobuyuki Kobayashi

Masakazu Ishikawa

Hiroshi Tamura

Toshihiko Muramatsu

Susumu Harada

Katsuhiko Kawai

Toshihiro Suzumura

Kenichi Nakamura

Mitsuo Nakamura

Shuji Sakakibara

Katsushi Kato

Takehiro Kikuchi

Hidehiko Inoue

Shunichiro Hiromasa

Kenji Urata

Kazumi Ishida

Kenji Ikuta

Naofumi Fukue

Nobuyuki Ito

Toshihiko Igashira

Atsushi Suzuki

Masatoshi Kuroyanagi

Keiji Wakahara

Akio Numazawa

Masahiko Miyaki

Kazuo Kobayashi

Shuichi Matsumoto

Yasumasa Kaji

Katsuhiko Nakabayashi

Yoshifumi Ina

Hirotada Yamada

Hiroyuki Nakamura

Jiro Kizaki

Hidehiko Asama

Yoshihiro Narahara

Yoshihiko Hirata

Yoshinori Mori

Masatada Yokoi

Sigenori Kitajima

Tokio Kurita

Masanori Midooka

Kouichi Aoyama

Hirofumi Shouda

Syohei Udo

Sumiko Kohira

Katuhiko Kodama

Sigenori Kitazima

Tetsuo Kaisaku

Yoji Mizuno

Shuziro Morinaga

Tasunori Kato

Kouji Horie

Yoshinori Moir

Kirou Kizaki

An O amount in the intake air is determined based on a fresh air and an EGR gas. A consumed O amount is determined with a command injection amount Qr. Then, the consumed O amount is subtracted from the O amount in the intake air to obtain an exhaust O amount. An exhaust O concentration is estimated based on the exhaust O amount. According to the invention, the system is not affected by a delay for the exhaust gas to reach an O sensor and a delay of the chemical reaction in the O sensor. Therefore, the exhaust O concentration can be highly precisely estimated compare to the case in which the exhaust O concentration is detected by the O sensor.

Control system for internal combustion engine

Even after initiation of a fuel cutting operation, an estimated coolant temperature value is continuously renewed based on an engine operating state until a predetermined time period elapses. Thus, an increase in the coolant temperature during the fuel cutting operation can be estimated. Furthermore, overestimation of the increase in the coolant temperature during the fuel cutting operation can be avoided since the renewal of the estimated coolant temperature after the elapse of the predetermined time period is prohibited. In this way, possible deterioration of coolant temperature estimation accuracy caused by the fuel cutting operation can be minimized, allowing more accurate coolant temperature estimation. As a result, when abnormality of a thermostat is judged based on a difference between an actual coolant temperature and the estimated coolant temperature value, misjudgment of a normal thermostat as an abnormal thermostat can be prevented.

Coolant temperature estimation system for estimating temperature of coolant of internal combustion engine

In a fuel infection valve, a valve chamber of a three ways valve is selectively communicated to drain and high pressure conduits and also communicated, via a main orifice, to a control chamber for controlling valve opening and closing operations of a nozzle needle. The control chamber may be communicated via the main orifice and the valve chamber to the drain conduit or the high pressure conduit, when a valve body is driven by a piezo actuator to open or close the drain conduit and close or open the high pressure conduit. The control chamber is always communicated via a sub orifice to the high pressure conduit without bypassing the three ways valve. Accordingly, hydraulic pressure in the control chamber is slowly decreased at a valve opening time and is rapidly increased at a valve closing time so that a lift characteristic of the nozzle needle is improved.

Fuel injection valve

A temperature projecting system includes a temperature sensor for monitoring a temperature of an objective portion where the temperature changes depending on an engine operating condition. The temperature projecting system projects an actual temperature of the objective portion based on the monitored temperature but free of a first-order lag of the temperature sensor. A temperature control system includes the temperature projecting system. The temperature control system derives a correction amount for a basic control amount of an actuator based on a difference between the projected actual temperature and a target temperature. The basic control amount is corrected by the correction amount to derive a corrected control amount which controls the engine operating condition and thus the temperature of the objective portion.

Temperature predicting system for internal combustion engine and

A fuel vapor purging control system for an internal combustion engine is provided. This purging control system incorporates an air/fuel ratio compensating system which includes a purge control valve for controlling a purge flow rate of an air-fuel vapor mixture flowing into an induction system of the engine through a purge passage according to a preselected engine operating condition parameter, a sensor disposed in the purge passage for determining an amount of fuel in the air-fuel vapor mixture, an air/fuel ratio controller for modifying an amount of fuel in an air/fuel mixture injected through a fuel injection system of the engine based on the amount of fuel in the air-fuel vapor mixture determined by the sensor for assuring a desired air/fuel ratio of the air/fuel mixture entering a combustion chamber of the engine.

Fuel vapor purging control system with air/fuel ratio compensating

A spark timing control system includes an engine state detecting device for detecting a state of an internal combustion engine. A vehicle vibration detecting device serves to detect a vibration of a vehicle in a longitudinal direction with respect to the vehicle. A target vehicle vibration value calculating device serves to calculate a target vehicle vibration value on the basis of one of results of detections by the engine state detecting device and the vehicle vibration detecting device. A control quantity setting device serves to set a control quantity of a spark timing so as to control the result of detection by the vehicle vibration detecting device at the target vehicle vibration value by use of an optimal feedback gain which is determined according to a dynamic model of the engine.

Spark timing control system for a vehicle-driving internal combustion

Speed control system for an internal combustion engine

There is disclosed a self-diagnosis apparatus in which when detecting a supply abnormally (i.e., failure to lead fuel evaporation gas into an intake passage), the abnormality can be accurately detected, taking into consideration variations in the fuel gas density (variations in the ambient temperature, variations in the volatility of the fuel, and etc.) due to the residual air in a fuel tank. In the apparatus, the amount of flow of the gas from the fuel tank to a canister can be detected, and a control circuit controls a purge valve to close a fuel gas discharge passage, and in this condition the control circuit detects the amount of flow of the gas from the fuel tank to the canister. When this flow amount exceeds a set value, the control circuit controls the purge valve to close and open the discharge passage, and judges in accordance with a change in an air-fuel ratio detected at this time by an O.sub.2 sensor whether or not any abnormality exists. If the control circuit judges by this judgment that there exists abnormality, the set value of the gas flow amount is set to a value greater than said set value, and the abnormality judgment is again effected. Then, if this judgment result still indicates that abnormality exists, a warning lamp is turned on to give warning.

Self-diagnosis apparatus in system for prevention of scattering of fuel

An air-fuel ratio feedback control apparatus for a gas engine. A mixer mixes intake air and a fuel gas. A subsidiary supply path supplies at least one of the intake air and the fuel gas downstream of the mixer. Oxygen concentration sensors detect a concentration of oxygen in an exhaust gas; and operation condition detectors detect operating conditions of the gas engine. A basic amount setting unit sets a basic amount of at least one of the intake air and the fuel gas supplied through the subsidiary supply path. A correction amount setting unit sets a correction amount proportional to a total fuel gas supply rate, and a control amount setting unit for setting a control amount of at least one of the intake air and the fuel gas supplied through the subsidiary supply path by adding the basic amount and the correction amount together, whereby the air-fuel ratio of the gas engine can be controlled at a desired value even when a bypass supply ratio of the fuel gas varies.

Air-fuel ratio control apparatus for engine

An air-fuel ratio control apparatus for an internal combustion engine which is equipped with an air-fuel ratio sensor for sensing an actual air-fuel ratio of a mixture to be introduced into the engine and a target air-fuel ratio setting section for setting a target air-fuel ratio of the engine. Also included is a controlled-amount calculating section for setting an optimal feedback gain on the basis of a predetermined dynamic model of the engine to calculate a controlled amount in accordance with the predetermined optimal feedback gain so that the actual air-fuel ratio becomes equal to the target air-fuel ratio. A fuel supply amount to the engine is determined on the basis of the calculated controlled amount, and the control responsiveness of the controlled-amount calculating section is suppressed when the engine is in a speed-decreasing state. This arrangement can adequately control the air-fuel ratio of the engine irrespective of the engine speed-decreasing state.

Air-fuel ratio control apparatus for use in engine

An air-fuel ratio control apparatus in which an air-fuel ratio of a mixture gas supplied to an engine, especially, a gas engine, is controlled in accordance with an output signal of each of oxygen concentration sensors disposed in upper and lower streams of an exhaust gas catalyzer of the engine. The output signal of the oxygen concentration sensor disposed on the upper stream side of the catalyzer is provided as one input signal of an air-fuel ratio control unit and the output signal of the oxygen concentration sensor disposed on the lower stream side of the catalyzer is provided as an input signal of an output signal correction amount determination unit, respectively. A mixing member for mixing an exhaust gas is disposed in an upper stream of each oxygen concentration sensor to detect the concentration of oxygen in the exhaust gas which is well mixed. The air-fuel ratio control unit controls an air-fuel ratio of a mixture gas in accordance with the output signal of the oxygen concentration sensor disposed on the upper stream side of the catalyzer and an output signal correction amount which is an output signal of the output signal correction amount determination unit. Since the exhaust gas is sufficiently mixed by the mixing member, variations of a measured value caused by the attachment position of each oxygen concentration sensor ar eliminated, thereby making it possible to control the air-fuel ratio of the mixture gas to a value close to a theoretical air-fuel ratio with a satisfactory precision.

A disc brake assembly includes a mounting member and two brake pads mounted on the mounting member on opposite sides of a disc to be acted upon the brake pads. The brake pads are mounted on backing plates which have circumferential ends disposed in facing relationship to torsion-resisting surfaces of the mounting member. The torsion-resisting surfaces have circumferentially extending projections which engage the backing plates in a manner resisting radial outward movement of the brake pads in response to frictional braking forces.

Disc brake pad assembly which resists radial outward displacement

An air-fuel ratio control apparatus for an engine for controlling a fuel injection amount so that an air-fuel ratio of a mixture gas which is supplied to the engine is set to a stoichiometric air-fuel ratio is disclosed. The apparatus has a first oxygen concentration sensor on the upstream side of a catalyst arranged in an exhaust pipe of the engine and a second oxygen concentration sensor on the downstream side, respectively. The first sensor gives to the apparatus a first linear detection signal for the air-fuel ratio of the mixture gas. The second sensor gives to the apparatus a second detection signal indicating whether the air-fuel ratio of the mixture gas is rich or lean for the stoichiometric air-fuel ratio. A target air-fuel ratio is set in accordance with the second detection signal and the first detection signal and the target air-fuel ratio are compared, thereby controlling a fuel injection amount. Thus, a deviation between the actual air-fuel ratio and the first detection signal can be accurately corrected and the air-fuel ratio can be accurately controlled to a value in a region where a high purification factor of the catalyst is derived.

Apparatus for controlling air-fuel ratio for engine

An engine control valve is disclosed which comprises a first bypass passage for introducing auxiliary air flow to an engine from an upstream side of an intake throttle valve disposed in an air intake pipe of the engine while bypassing the intake throttle valve; a second bypass passage having an inlet port in communication with an outlet port of the first bypass passage, for introducing the auxiliary air flow, introduced through the inlet port, to a downstream side of the intake throttle valve; a valve body for changing an opening area of at least one of the outlet port of the first bypass passage and the inlet port of the second bypass passage, thereby adjusting an amount of the auxiliary air flow to be introduced from the upstream side to the downstream side of the intake throttle valve; and a drive unit for driving the valve body in accordance with a drive signal outputted from the control unit. When a maximum drive signal is inputted into the drive unit, the opening area of at least one of the outlet port of the first bypass passage and the inlet port of the second bypass passage is throttled so that a predetermined amount of the auxiliary air flow smaller than a maximum amount of the auxiliary air flow may be introduced into the downstream side of the intake throttle valve.

Engine idle control valve

A disc brake assembly includes a disc rotor rotated with a wheel in a body, a mounting member fixed to a stational member of vehicles and having an arm portion in which a pair of grooves extending toward to the axial direction of the disc rotor are provided therein. A brake pad disposed to at least one side of the disc rotor and having a pair of ear portions which are outwardly projected at the center portion or the outer side of both ends in the rotational direction of the disc rotor of its backing plate, respectively and which are fitted into a pair of groove portion formed in the arm portion of the mounting member and slidably supported on the arm portion of the mounting member toward to the axial direction of the disc rotor. The brake pad has a backing plate in which end surfaces in the rotational direction of the disc rotor of the rotational center side of the disc rotor from the each ear portion are formed in wedge-shape in the diameter direction of the disc rotor and the mounting member has torque resisting surfaces opposed to the rotational center side of the disc rotor from each ear portion of the end surfaces of the backing plate in the rotational direction of the disc rotor at its arm portion and formed in V-shape in corresponding to the backing plate. Since the brake pad is held under a stable condition in the diameter direction and the rotational direction of the disc rotor and is prevented from movement, it is able to fundamentally prevent generation of the uncomfortable squeak noise of the disc brake assembly caused by movement of the brake pad.

Disc brake assembly

Growing community of inventors

Kariya, Japan

Toshio Kondo