Abstract: An NO.sub.x absorber (18) is arranged in an exhaust passage of an internal combustion engine. The NO.sub.x absorber (18) absorbs the NO.sub.x when the air-fuel ratio of the exhaust gas flowing into the NO.sub.x absorber (18) is lean while releases the absorbed NO.sub.x when the air-fuel ratio of the exhaust gas flowing into the NO.sub.x absorber (18) becomes the stoichiometric air-fuel ratio or rich. An air-fuel ratio sensor (22) is arranged in the exhaust passage downstream of the NO.sub.x absorber (18). When the air-fuel ratio detected by the air-fuel ratio sensor (22) is switched from lean to rich after the air-fuel ratio of the exhaust gas flowing into NO.sub.x absorber (18) is switched from lean to rich, it is decided that the releasing action of NO.sub.x from the NO.sub.x absorber (18) is completed.

Abstract: A NO.sub.x absorbent (18) which absorbs the NO.sub.x when the air-fuel ratio of the exhaust gas flowing into the NO.sub.x absorbent (18) is lean and releases the absorbed NO.sub.x when the oxygen concentration of the exhaust gas flowing into the NO.sub.x absorbent (18) is lowered, is arranged in the exhaust passage of the engine. The amount of alkali metals, alkali-earth metals or rare-earth metals contained in the NO.sub.x absorbent (18) positioned on the downstream side, is made lower than the amount of alkali metals, alkali-earth metals or rare-earth metals contained in the NO.sub.x absorbent (18) positioned on the upstream side, to increase a reducing ability of the NO.sub.x absorbent (18) positioned on the downstream side as compared to the reducing ability of the NO.sub.x absorbent (18) positioned on the upstream side.

Abstract: A measuring device for measuring a fuel injection quantity comprising fuel volume sensing means including a fuel injection chamber connected to a fuel injection valve and receiving the fuel injection quantity therefrom, a back pressure chamber which faces the fuel injection chamber, bulkhead means located between the fuel injection chamber and the back pressure chamber as an intercept therebetween and responsive to the fuel injection quantity for generating a displacement, sensing means for sensing the displacement of the bulkhead means, pressure means for holding a pressure of the back pressure chamber to be of a constant value, fuel injection quantity computing means responsive to the sensing means for determining a fuel injection quantity, discharging means including fuel discharging means for discharging the injected fuel quantity from the fuel injection chamber to its exterior, discharging quantity computing means responsive to the fuel injection quantity computing means for computing a discharged quanti

Abstract: A fuel supply device in which a regulator pressurizes fuel fed to a fuel injector to adjust the fuel to a predetermined pressure according to an engine condition. The regulator has a piston in a housing to form a control chamber and a high pressure chamber therein. The high pressure chamber is communicated with the fuel injector and a pump chamber of a high pressure pump discharging a highly pressurized fuel. The control chamber is connected to a pressure source generating a high pressure according to an engine condition. The piston moves in response to the pressure in the control chamber to pressurize the fuel in the high pressure chamber.

Abstract: A device for varying a valve timing and lift for an internal combustion engine comprises a first valve lifter and a second valve lifter, and an oil pressure chamber being defined between the first valve lifter and the second valve lifter. The flow of oil from the oil pressure chamber is continuously and steplessly controlled through a high-speed response control valve in an oil extraction passage. While the oil is being removed, the valve does not lift. When the high-speed response control valve is closed, the first valve lifter and the second valve lifter move together and the valve begins to lift. By controlling the action of the actuator of the high-speed response control valve, the valve timing and lift of the poppet valve can be controlled to the optimum ones matching the engine operating conditions.

Abstract: A fuel injection apparatus including a fuel injector, a high pressure feed pump, and an auxiliary pump. The high pressure feed pump supplies highly pressurized fuel to the fuel injector while the engine is driven. The auxiliary pump supplies highly pressurized fuel at least on starting of the engine. The auxiliary pump is driven independent of the engine while the high pressure feed pump is driven by the engine.

Abstract: A position detector for detecting the piston TDC position in a piston engine has a cylindrical casing penetrating the top wall defining a combustion chamber of the engine and fixed thereto, a light emission element, a light reception element each being accommodated within the upper half of the casing, an inlet optical fiber connected to the light emission element and an outlet optical fiber connected to the light reception element. These optical fibers are inserted into the lower half of the casing. The lower end of each optical fiber is opposed to the upper surface of the piston at a predetermined distance therefrom when the piston is located in the vicinity of the TDC position. The light emitted by the light emission element is applied to the upper surface of the piston, after passing the inlet optical fiber. The reflected light from the upper surface of the piston is received and sent to the light reception element by the outlet optical fiber.

Abstract: An internal combustion engine comprises a cylinder block and a cylinder head. A combustion chamber is formed in the cylinder block and the cylinder head. An accumulation chamber is formed within the cylinder head and communicated with the combustion chamber via an operating valve. The accumulation chamber is disposed adjacent to an exhaust port of the engine and is heat exchangeable with the exhaust port. The operating valve is opened approximately at the time the compression stroke is commenced and is closed approximately at the time the compression stroke is completed. A cap is disposed at the entrance of the accumulation chamber and has a plurality of jets formed thereon. The compressed combustible gas mixture is accumulated within the accumulation chamber, heated by the heat transmitted from the exhaust port and spouted out into the combustion chamber, so that approximately uniform turbulences are generated in the combustion chamber and the flame speed is increased.

Abstract: The temperature and air-fuel ratio of the exhaust gases of an internal combustion engine are sensed to generate signals indicative thereof and the amount of fuel to be injected into the engine is determined in accordance with the signals, thus controlling the air-fuel ratio at a predetermined value and thereby decreasing the abnormal temperature rise in the exhaust system.

Abstract: An apparatus for detecting knock for an internal combustion engine having a plurality of cylinders in which a vibration sensor is attached to each cylinder and a peak value of vibration detected by the sensor is sampled over a predetermined range near the top dead center. The sampled value is converted from analog to digital and stored for a predetermined number of sampling times to obtain the average value for each cylinder. Then the frequency of occurrences in which the ratio between the sampled peak value and the average value exceeds a reference value is obtained, and the knock is determined when the frequency of occurrences in any one cylinder exceeds a predetermined value or when the average frequency of occurrences of the all cylinders exceeds another predetermined value.

Abstract: An exhaust gas recirculation system comprises a speed detector for generating an engine rotational speed signal and a reference rotational position detection signal, a pressure sensor for detecting the negative pressure in the intake pipe of an engine to generate a negative pressure signal, a microcomputer responsive to the negative pressure signal and the rotational speed signal generated at the reference rotational position of the engine to compute an amount of exhaust gas recirculation in synchronism with the reference rotational position detection signal, and an electronic control circuit for controlling the opening of an exhaust gas recirculation control valve in accordance with the computed amount.

Abstract: An internal combustion engine comprising an intake duct and a turbocharger arranged in the intake duct. A primary throttle valve connected to the accelerator pedal is arranged in the intake duct located downstream of the turbocharger. A secondary throttle valve is arranged in the intake duct located downstream of the primary throttle valve. An auxiliary intake passage is branched off from the intake duct located between the primary and the secondary throttle valves and is connected to the intake passage located downstream of the secondary throttle valve. The secondary throttle valve is gradually closed from the full open position as the level of the vacuum or the positive pressure, which are produced in the intake duct located between the primary and the secondary throttle valves, is increased.

Abstract: An internal combustion engine comprising a carburetor having a throttle valve. A secondary throttle valve is arranged in the intake passage at a position located downstream of the throttle valve of the carburetor. When the engine is operating under a light load, the secondary throttle valve remains fully closed. When the engine is operating under a heavy load, the secondary throttle valve remains fully opened. The intake passage located upstream of the secondary throttle valve is interconnected with the intake passage located downstream of the secondary throttle valve via an auxiliary intake passage having a cross-sectional area which is extremely smaller than that of the intake passage.

Abstract: An internal combustion engine with an exhaust gas accumulation chamber, a valve for controlling the flow of the exhaust gas into and from the exhaust gas accumulation chamber and a communicating passage for communicating the cylinder bore of the combustion chamber with the exhaust gas accumulation chamber, along which cylinder bore the piston is reciprocated. The valve is open from a first time in the compression stroke to a second time in the succeeding expansion stroke. Due to the combined operation of the valve and the movement of the piston, the exhaust gas is accumulated within the accumulation chamber only near the end of the expansion stroke and is spouted from the accumulation chamber only in the beginning of the compression stroke. The communicating passage is so arranged that the exhaust gas spouted from the accumulation chamber into the combustion chamber generates a swirl motion in the combustible gas mixture.

Abstract: An internal combustion engine includes a duplex carburetor, an engine cylinder, a pair of primary and secondary venturis and an intake manifold connected between the cylinder and the carburetor, the manifold having a common chamber located downstream of the venturis and a pair of primary and secondary branch intake passages opening to the cylinder through a pair of intake ports, respectively. There is a valve in the secondary intake passage for controlling the flow of air-fuel mixture therethrough, the valve being opened by a control mechanism including a vacuum servo which receives a vacuum signal from a port opening to the secondary venturi for actuating link means connected to the control valve. The secondary passage is normally blocked and is only opened when the engine rotates at high speed under heavy load.

Abstract: In an exhaust gas recirculation system adapted to an internal combustion engine, the system comprises a servomotor to be operated by pneumatic pressure and a control valve actuated by the servomotor to control the quantity of exhaust gases recirculated into an intake manifold from an exhaust pipe. The pneumatic pressure applied to the servomotor is electrically controlled without undesired errors to satisfy the following function in relation to the engine intake manifold vacuum and the engine speed:Pe=f(Pv, N)where Pe is the pneumatic pressure applied to the servomotor, Pv and N respectively indicate the engine intake manifold vacuum and the engine speed.

Abstract: A multi-cylinder engine comprising an intake manifold equipped with a carburetor. A secondary throttle valve is provided for each cylinder. Each of the secondary throttle valves is arranged in the respective manifold branch and fixed onto a common throttle shaft. An auxiliary intake passage is branched off from the collecting portion of the intake manifold and connected to a distribution channel. Each of the intake ports is connected to the distribution channel via a corresponding channel branch which opens into the intake port at a position near the intake valve. The common throttle shaft of the secondary throttle valves is connected to a vacuum operated diaphragm apparatus so that the secondary throttle valves are opened in accordance with a reduction in the level of vacuum produced in the intake manifold.

Abstract: In a carburetor for an internal combustion engine, a control valve is disposed with an air passage through the carburetor structure to control the flow quantity of air to be mixed with fuel from a float chamber and a pneumatic servo-motor is operatively connected with the control valve to control the opening degree of the valve. The pneumatic pressure applied to the servo-motor is electrically controlled to satisfy the following function in relation to the engine intake manifold vacuum and the engine speed.Pd=f(Pv, N)where the character Pd is the pneumatic pressure applied to the servo-motor, and the characters Pv and N respectively indicate the engine intake manifold vacuum and the engine speed.

Abstract: In a carburetor and an exhaust gas recirculation system adapted to an internal combustion engine, the system comprises a first servomotor to be operated by pneumatic pressure and a first control valve actuated by the first servomotor to control the quantity of exhaust gases recirculated into an intake manifold from an exhaust pipe, and the carburetor comprises a second servomotor to be operated by pneumatic pressure and a second control valve actuated by the second servomotor to control the flow quantity of air to be mixed with fuel from a float chamber. The pneumatic pressure applied to the first and second servomotors is electrically controlled to satisfy the following function in relation to the engine intake manifold vacuum and the engine speed.Pe=f(Pv, N)where Pe is the pneumatic pressure applied to the servomotors, Pv and N respectively indicate the engine intake manifold vacuum and the engine speed.

Abstract: A multi-cylinder internal combustion engine having a plurality of cylinders, each comprising a combustion chamber and an accumulation chamber which are interconnected to each other via an accumulation valve. The accumulation chambers are interconnected to each other via a common connecting passage. The opening operation of the accumulation valve is controlled so that the accumulation valve remains opened during the compression stroke. In the first half of the compression stroke, a jet of the combustible mixture is spouted out into the combustion chamber from the accumulation chamber to create a strong swirl motion in the combustion chamber. In the latter half of the compression stroke, the combustible mixture in the combustion chamber flows into the accumulation chamber to accumulate the combustible mixture under high pressure, which is spouted out into the combustion chamber at the next cycle.