Mazda Motor Corporation

Eiji Nishimura

Toshihiro Matsuoka

Takahisa Ishihara

Kazutoshi Nobumoto

Kenichi Watanabe

Kaoru Sotoyama

Toshiaki Tsuyama

Hirofumi Nishimura

Junichi Taga

Osamu Kameda

Koichi Hatamura

Tomoji Izumi

Mitsuru Nagaoka

Takahiro Inada

Tsunehisa Okuda

Hiroyuki Takebayashi

Kouji Miyamoto

Satoru Ando

Kazuyoshi Okuda

Kenji Shimizu

Akiko Honda

Toshihiro Matuoka

Tamio Hirasawa

The present invention has an object to effectively prevent deterioration of combustion characteristics when engine temperature is low. There is provided an intake pressure controller that effects control such that, when an operating condition discriminator that identifies engine temperature identifies low engine temperature after engine start-up, control by an engine controller (feedback controller ) that performs engine control on fluctuation of intake negative pressure to decrease the intake negative pressure is suppressed until the temperature of the intake passage rises to at or above a predetermined value, and such that the intake negative pressure is made larger.

Engine control system

An engine control system for controlling combustion of an internal combustion engine equipped with an exhaust gas purifying catalyst. The system controls fuel combustion on the basis of control parameters including air/fuel ratio, ignition timing and intake air flow so as to cause a rise in exhaust gas temperature while an exhaust gas purifying catalyst installed in an exhaust line of the engine is insufficiently warmed or inactive. When a fluctuation of engine speed is detected, the system controls the air/fuel ratio to reach a target value close to a stoichiometric value, for example, a value between 13 and 17, and controls a control parameter other than air/fuel ratio so as to bring the fluctuation of engine speed within limits of stable combustion while the exhaust gas purifying catalyst is insufficiently warmed. The air/fuel ratio feedback control may be commenced immediately after an engine start.

Fuel combustion control system for engine

A fuel combustion control system for an internal combustion engine having an exhaust gas purifying catalyst installed in an exhaust line therein advances an ignition timing to try to stabilize combustion when a fluctuation of engine speed is larger than a limit speed on stable combustion and further retards an ignition timing to accelerate a rise in catalyst temperature together with securing combustion stability while the engine is still cold or when a fluctuation of engine speed is smaller than the limit speed on stable combustion.

An engine control device has an idle speed control of an engine by an ignition timing control and an idle speed control by air-by-fuel ratio feedback. This engine control device detects roughness caused by a torque change on the basis of a change in angular velocity of a crank shaft, sets a control gain depending on the roughness, reflects the control gain on the idle speed control by the ignition timing control, thereby harmonizing the idle speed control of the engine by the ignition timing control with the idle speed control by the air-by-fuel ratio feedback.

Idle speed control device for engine

A vehicle which can execute both vehicle-speed based auto-cruising control and vehicle-interval distance based auto-cruising control has a single operation knob having a SET switch, a RESUME switch, and a COAST switch. In order to allow the single operation knob to set both a target vehicle speed and a target vehicle-interval distance, when the SET switch is operated during the vehicle-speed based auto-cruising control, a vehicle speed at the time of the operation or at the end of the switch operation is set to be the target vehicle speed; when the SET switch is operated during vehicle-interval distance based auto-cruising control, a vehicle-interval distance at the time of the operation or at the end of the switch operation is set to be the target vehicle-interval distance.

Cruise controller for vehicles

In a vehicle which sets a target vehicle-interval distance, and can execute auto-cruise control for controlling the vehicle speed so as to maintain the target vehicle-interval distance, when the auto-cruise control is not executed, a vehicle-interval distance to be set by a driver is detected together with the vehicle speed at that time. A plurality of sets of the vehicle speed and vehicle-interval distance data are accumulated, and the relationship between the vehicle speed and the vehicle-interval distance is calculated. Upon execution of the auto-cruise control, a vehicle-interval distance corresponding to the vehicle speed at that time is obtained from the calculated relationship, and the obtained vehicle-interval distance is set to be the target vehicle-interval distance.

A system for controlling a supply of driving power to an automotive vehicle having driving wheels and an internal combustion engine includes a supercharger, which is capable of maintaining a supercharging pressure, for charging intake air into the internal combustion engine, and an automatic transmission having a shifting characteristic including a down-shifting zone with a specified width. The automatic transmission is capable of shifting among gear stages and transmitting driving power generated by the internal combustion engine to the driving wheels. A first adjustment device controls the supercharging pressure of the supercharger to converge on a target supercharging pressure. A second adjustment device causes the automatic transmission to shift from one gear stage to another gear stage. A detection device determines an acceleration requirement level by detecting an opening angle of an accelerator pedal. A control device changes (i) the target supercharging pressure and (ii) the shifting characteristic of the automatic transmission, in accordance with the acceleration requirement level determined by the detection device such that the target supercharging pressure is lowered and the down-shifting zone of the shifting characteristic of the automatic transmission is widened when (i) the automatic transmission shifts to a higher vehicle speed gear stage and (ii) the acceleration requirement level increases.

System for controlling driving power for a supercharged automotive

A throttle actuator opens and closes the throttle valve of an engine in response to movement of an accelerator pedal. Throttle opening characteristics which determines a target throttle opening for a given amount of depression of the accelerator pedal is set so that the accelerator depression fluctuation rate is minimized when the power mode is selected and so that the fuel consumption rate is minimized when the economy mode is selected.

Engine output characteristic control system for vehicle

A clutch control apparatus for a mechanical supercharger is used in connection with a mechanical supercharger provided in the intake passage of an engine and driven by the output shaft of the engine through a clutch. The clutch control apparatus suppresses shock during clutch engagement and increases clutch life by controlling the slipping condition of the clutch when the mechanical supercharger is engaged.

Clutch control apparatus for a mechanical supercharger

A control system for a power train having an engine, an automatic transmission, and a supercharger provided in an intake passage of the engine for supplying compressed air into a cylinder of the engine includes a first detector for detecting a demand for adding supercharging power, a second detector for detecting a demand for shifting the gear stage of the automatic transmission, and a controller for controlling both the supercharger and the automatic transmission in response to the first and the second detectors so that the supercharger and the automatic transmission have an interrelation with respect to the initiation of their respective operations when both the demand for adding the supercharger power and the demand for shifting the gear stage of the automatic transmission occur at the same time.

Control system for a power train

A four wheel drive system for a vehicle includes comprising a power plant for producing a driving force, a front wheel driving mechanism for transmitting the driving force to drive right and left front wheels, a rear wheel driving mechanism for transmitting the driving force to drive right and left rear wheels, and right and left wheel clutches provided in one of the driving mechanisms for controlling the amount of the driving force transmitted to the wheels. A cut-off clutch is provided for controlling the driving force transmitted to the wheels of the one of the driving mechanisms, and a control device causes the cut-off clutch to engage before the wheel clutch is engaged. The driving force is transmitted sequentially rather than instantly from the cut-off clutch, the wheel clutches and to the wheels so as to suppress the torque shock creative in connection with a change in the drive condition.

Four wheel drive system

A four wheel drive system of a vehicle including a power plant for producing driving force, has a front wheel driving mechanism for transmitting the driving force to drive a right and left front wheels and rear wheel driving mechanism for transmitting the driving force to drive right and left rear wheels. Right and left wheel clutches provided in one of the driving mechanisms for control the amount of the driving force transmitted to the wheels, and steering angle detecting device detects a steering angle of a steering wheel. A control device increases torque distribution for the rear wheel driving mechanism in a cornering condition of the vehicle as a steering angle change rate is increased. The system provides the vehicle with a desirable torque distribution during a cornering operation so that improved cornering property is obtained.

A drive control system of a four-wheel drive vehicle has a differential device interposed between front and rear wheels and a differential restricting device mounted to the differential device. The differential restricting device is subjected to feedback control so as for the wheels to reach a target slip ratio. In this control, a control target value is given by way of slip ratios of the wheels and the target slip ratios are then converted into a wheel speed difference between the front and rear wheels. The feedback control of the differential restricting device is performed by comparing the target wheel speed difference with an actual wheel speed difference between the front and rear wheels.

Drive control system of four-wheel drive vehicle

A power train control system for controlling power to be transmitted to a traction wheel of a vehicle from a vehicle engine through an automatic transmission shifts its speed range according to shift patterns depending upon speed of the vehicle and a load of the vehicle engine. When slippage occurring on the traction wheel is detected, the automatic transmission is caused to shift its speed range according to a specific shift pattern for traction control which predetermined according to at least a rotational speed of a driven wheel of the vehicle so as to control the power transmitted to the traction wheels from the vehicle engine, thereby eliminating the slippage.

Method and system for controlling power train of vehicle

An automatic speed control system for a vehicle includes an automatic transmission, a speed change switch for producing signals for changing a vehicle speed, and a shift down control device. The shift down control device carries out a shift down operation of the automatic transmission of the vehicle under a certain vehicle driving condition when the shift down control device receives the signals from the speed change switch. A gradient detecting device detects a gradient of a running path on which the vehicle is driven, and shift down prohibiting device prohibits the shift down operation even where the speed change switch is actuated to the vehicle speed at least when the gradient of a running path detected is greater than a predetermined value so that unnecessary shift changes are suppressed.

Growing community of inventors

Hiroshima, Japan

Eiji Nishimura