Abstract: This invention relates to a 4-cycle in-cylinder injection internal combustion engine in which fuel is injected directly into a combustion chamber, and specifically to an in-cylinder injection internal combustion engine suited for use as an internal combustion engine which performs premixed combustion at the time of a high power output but stratified combustion at the time of a low power output and switches the state of each of the combustions depending on an operation state of the engine.

Abstract: A combustion control system for a lean-burn engine, to be mounted on an automotive vehicle, uses probabilistic and statistical nature of combustion variance upon lean-burn operation to obtain reliable combustion control. The system detects a variance value in angular acceleration of a rotating member driven by the engine, normalizes the variance value in accordance with an operating state of the engine to determine a normalized variance value. The system also compares the normalized variance value with a predetermined threshold value to obtain a deteriorated combustion determining value. The system compares the deteriorated combustion determining value with a predetermined reference value and controls a combustion variance adjustment element so that the deteriorated combustion determining value matches the reference value.

Abstract: An apparatus for controlling an internal combustion engine having an exhaust purifying catalytic device which absorbs nitrogen oxides contained in exhaust when the engine is in a lean-combustion mode and which deoxidizes the absorbed nitrogen oxides when the engine is in a rich-combustion mode. The engine control apparatus includes an electronic control unit for estimating the amount of purifying capability reducing substances other than nitrogen oxides, which decreases the nitrogen oxide adsorbing ability of the catalytic device, absorbed by the catalytic device, on the basis of the accumulated value of vehicle travel distance, fuel consumption of engine, or intake air amount. The control unit changes the operating condition of engine so that the exhaust gas temperature is increased when it is judged that the estimated adsorption amount has reached a predetermined adsorption amount.

Abstract: An internal combustion engine according to this invention is provided with intake ports each of which is formed to guide a flow of inducted air in a particular direction. Each intake port includes, in the vicinity of its corresponding intake opening to a combustion chamber, a bent port portion bent at a greater curvature than a port portion on a side upstream of the bent port portion. The bent port portion has a greater inner diameter than the inner diameter of the corresponding intake opening, whereby air can be inducted in a sufficient amount without deterioration to the directing function for air to be inducted into the combustion chamber.

Abstract: A stratified burning internal combustion engine according to this invention is equipped with an intake port and a fuel feed device so that stratified tumble flows of different fuel concentrations can be formed in a combustion chamber. An ignition device is provided in the combustion chamber to ignite at least one of the tumble flows, said at least one tumble flow being rich in fuel. To promote the stratified tumble flows, a top wall of a piston has an inclined wall. This makes it possible to strengthen the tumble flows, whereby the stratification of an air-fuel mixture in the combustion chamber can be improved further to permit lean burn at a larger air/fuel ratio.

Abstract: An air fuel ratio detecting device which is improved in accuracy as compared to similar prior art devices comprises a sensor cell for developing an electrical signal in response to the difference between the concentration of oxygen within an exhaust gas and the concentration of oxygen within a reference gas, a controlling means for developing an electrical control signal having a polarity determined from the output of the sensor cell, a pump cell for moving oxygen ions in response to the electrical control signal received from the controlling means, a control current detecting means for detecting control current flow between the controlling means and the pump cell, an air fuel ratio detecting means for detecting an air fuel ratio from the control current flow, a stoichiometric air fuel ratio detecting means for detecting the direction of the control current flow so as to determine the stoichiometric air fuel ratio, a storage means for storing therein a linear air fuel ratio value which is determined from a pr

Abstract: An exhaust emission control system for a motor vehicle is disposed in an exhaust path, comprises a first catalyst for purifying an exhaust gas during activation of an engine, a second catalyst disposed downstream of the first catalyst and including a lean NOx catalyst, a bypass detouring the first catalyst, a select valve for controlling the amount of exhaust gas to be introduced into the bypass and first catalyst, and a control unit for controlling the select valve and flow of the exhaust gas according to operating status of the engine.

Abstract: An internal combustion engine according to this invention is provided with intake ports and an injector. The intake ports are designed to form stratified tumble flows of different fuel concentrations in a combustion chamber. A spark plug is arranged in the combustion chamber to ignite one of the tumble flows, which one tumble flow is rich in fuel. Each intake port is provided with a longitudinal partition which divides an interior of the intake port into two passages. These longitudinal partitions are formed in such a way that, of the air-fuel tumble flows formed around the spark plug, the tumble flow closest to the spark plug is formed of a richer air-fuel mixture. Each longitudinal partition is arranged only on a side upstream of a valve stem of an intake valve in the corresponding intake port, so that a sufficient amount of intake air can be obtained while extremely minimizing a reduction in the actual cross-sectional flow area.

Abstract: This invention relates to an intake port structure for an internal combustion engine. It is an object of the present invention to increase the strength of tumbling without lowering the maximum flow rate. An intake port (44) is constructed broader in a tumble-flow-side half (44a) than in the other half (44b) to have an intake air flow through the intake port (44) off-centered toward the side of a tumble flow, whereby an intake air flow from the intake port (44) promotes the tumble flow.

Abstract: An engine controlling system for a vehicle which is suitable for use with an automobile. When an accelerated/decelerated condition detecting means detects an inoperative condition of an acceleration/deceleration instructing means and develops a non-operation detection signal, a constant speed running designation signal is developed from a constant speed running designating means, and an aimed speed setting means sets a speed of the vehicle to be aimed when the vehicle should make constant speed running. Then, a constant speed running controlling means controls an engine output adjusting means in response to a running speed detection signal from a running speed detecting means so that the running speed of the vehicle may become equal to the aimed speed. The engine output adjusting means thus adjusts the output power of an engine carried on the vehicle. Consequently, the vehicle thereafter makes constant speed running at a speed equal to the aimed speed.

Abstract: An engine controlling system for a vehicle is disclosed which is suitable for use with an automobile. When a treadled condition detection signal is developed from an accelerator pedal operated condition detector, a first control amount setting device sets a control amount of an engine output adjusting device in accordance with an operation amount detection signal. When a treadled condition cancelling detection signal is developed from the accelerator pedal operated condition detector, a second control amount setting device sets, if it receives a constant speed running designating signal from a running condition designating device in accordance with a running speed detection signal from a running speed detector, a control amount of the engine output adjusting device necessary to make the running speed of the vehicle equal to an aimed speed.

Abstract: An engine controlling system for a vehicle suitable for use with an automobile. When a running condition change-over means develops a constant speed running designating signal, an aimd torque calculating means calculates an aimed output torque of an engine of the vehicle in accordance with an aimed speed, but when the running condition change-over means develops an accelerated running designating signal, the aimed torque calculating means calculates an aimed output torque of the engine in accordance with an aimed acceleration. Meanwhile, an engine output torque detecting means calculates an output torque of a torque converter in accordance with characteristics of the torque converter and an engine rotational speed detection signal detected by an engine rotational speed detecting means and outputs the output torque as a measured value of the output power of the engine.

Abstract: In a cooling apparatus for an engine, a water jacket is divided into two parts, namely a forcible circulation part located chiefly round a cylinder head, and a natural convection part located chiefly round a liner of a cylinder block. The natural convection part is filled at its upper space with a cooling water and at its lower space with a cooling medium different from the cooling water. The cooling medium has a boiling point around a temperature zone to cool the liner, and also has a specific gravity larger than that of the cooling water and immiscible with the cooling water.

Abstract: Disclosed herein is an air/fuel ratio controller for an engine, which is equipped with a function to make the air/fuel ratio leaner in a light-load operation zone or the like of a lean burn engine. The controller is intended to improve the starting performance and acceleration feeling of the engine significantly. Upon generation of an acceleration command by a driver during lean burn of the engine at a lean air/fuel ratio, an air/fuel ratio enriching device is operated to set the air/fuel ratio of an air-fuel mixture, which is to be fed to the engine, at a level richer than the lean air/fuel ratio while an actually accelerated state continues in the engine from the time point of generation of the acceleration command.

Abstract: An air fuel ratio detecting device which is improved in accuracy as compared to similar prior art devices comprises a sensor cell for developing an electrical signal in response to the difference between the concentration of oxygen in the exhaust gas and the concentration of oxygen in a reference gas, a controlling means for developing an electrical control signal having a polarity determined from the output of the sensor cell, a pump cell for moving oxygen ions in response to the electrical control signal received from the controlling means, a control current detecting means for detecting control current flow between the controlling means and the pump cell, an air fuel ratio detecting means for detecting the air fuel ratio from the control current flow, a stoichiometric air fuel ratio detecting means for detecting the direction of the control current flow so as to determine the stoichiometric air fuel ratio, a storage means for storing therein a linear air fuel ratio value which is determined in a predetermi

Abstract: An intake port device comprises an intake port (9) formed by a straight part (13) and a helical part (15), and a valve (17) disposed adjacent to the inlet of the intake port. In order that intake air flow having a large swirl ratio can be supplied to an engine without being encountered with a large resistance even in a light-loaded condition of the engine, the valve (17) is held in its closed position without causing any sharp decrease in the coefficient of intake air flow when closed. In a modification of the intake port device, the valve (17) holds open the lower half of the intake port 9 in its closed position, so that intake air flow having a large swirl ratio can be supplied without being encounted with a large resistance even when the load of the engine is light. In another modification of the intake port device, the free end of the valve (17) is bent and deformed in the downstream direction of intake air so that the flow of intake air may not be encountered with a large resistance.

Abstract: An engine cooling device comprises an oil jacket surrounding a cylinder portion of an engine, an oil gallery supplying high-pressure oil to various parts of the engine, and an oil pressure regulator disposed between the oil jacket and the oil gallery to reduce the pressure of the high-pressure oil supplied from the oil gallery and to supply the oil at a reduced pressure to the oil jacket. Thus, the required mechanical strength of the oil jacket can be decreased to decrease the weight of the engine cylinder block.

Abstract: An intake device for an internal combustion engine, in which the intake port is formed to a specific shape without using a partition plate, provided with a valve at its inlet, and the flow direction of intake air to the combustion chambers can be varied by controlling the opening of the valve, thereby providing easy manufacture and reduced cost of the intake port and improved performance when the engine is heavily loaded.