Abstract: An engine intake system including a main intake passage leading through an intake port to a combustion chamber, an auxiliary intake passage branched from the main intake passage and opened to the intake passage, and a control valve provided in the main intake passage and adapted to be opened under a heavy load engine operation and closed under a light load engine operation. A fuel injection valve is provided in the auxiliary intake passage close to the opening of the intake port to the combustion chamber to inject fuel toward the combustion chamber.

Abstract: A valve driving system for an internal combustion engine having two intake valves and/or two exhaust valves for each cylinder, which includes a cam shaft formed with a pair of low speed cams and a high speed cam located at substantially the center part of the cam shaft, a pair of first rocker arms driven by the low speed cams respectively, each having a portion engaged with one of the valves, second rocker arms driven by the high speed cam and located between the first rocker arms, two oil pressure chambers formed in the second rocker arm and facing the respective first rocker arms, two plungers, each being provided in one of the oil chambers, two bores each being formed engageably with one of the plungers in one of the first rocker arms, an oil passage formed in the second rocker arm and communicated with both oil pressure chambers, and a control valve for controlling oil pressure fed to the oil passage in accordance with the engine operating condition.

Abstract: In an internal combustion engine having a pair of intake valves, the valve driving system for timing the intake valves is provided with a valve timing changing mechanism for changing the timing of at least one of the intake valves. The valve timing changing mechanism retards or advances the timing of said one intake valve to change the total intake valve opening time, i.e., the time that at least one of the intake valves is open, according to the operating condition of the engine.

Abstract: In an internal combustion engine, the movement of the cam on the camshaft is transmitted to each valve of each cylinder by way of a tappet member. The tappet member is held in a swinging member which can be swung about the camshaft. The swinging member is swung about the camshaft back and forth in the rotational direction of the camshaft by a control device according to the operating condition of the engine. When the swinging member is swung about the camshaft, the relative position of the tappet member to the cam at a given angular position of the camshaft is changed, whereby the valve timing of the valve associated with the tappet member is changed.

Abstract: A valve mechanism for an internal combustion engine has a valve and a cam on a camshaft for operating the valve. A swingable member is provided for swinging movement about the camshaft and has a tappet receiving hole. A tappet slidably received in the hole is driven by the cam and in turn drives the valve. The valve timing can be changed by swingably moving the swingable member. A control device is provided for holding the swingable member at a position wherein the direction of movement of the tappet is aligned with the direction of movement of the valve under a heavy load, high speed engine operation and moving the swingable member to another position wherein the direction of movement of the tappet is inclined with respect to the direction of movement of the valve under a light load, low speed operation to change the valve timing.

Abstract: A multiple-displacement engine which can be operated either in a full-displacement state in which all the cylinders are operative or a part-displacement state in which a part of the cylinders are inoperative is provided with a balancer for attenuating torque fluctuation due to explosion in the operative cylinders in the part-displacement state of the engine. The engine is further provided with a balancer actuator which actuates the balancer when the engine is operated in the part-displacement state.

Abstract: An engine intake system includes a combustion chamber, a first intake port opening to the combustion chamber, and a second intake port opening to the combustion chamber. A shut-off valve is provided for blocking intake gas flow to the combustion chamber through the second intake port in a first engine operating region wherein engine load is relatively small, and allowing the intake gas to flow to the combustion chamber through the second intake port in a second engine operating region wherein the engine load is relatively large. A first valve actuating mechanism is provided for opening the first intake valve at a first timing, and a second valve actuating mechanism is provided for opening the second intake valve at a second timing.

Abstract: A method which comprises drawing a part of the reaction liquid from a reactor for unsaturated polyesters, bringing the drawn liquid into contact and reaction with a gaseous starting material or a liquid starting material capable of being converted into vapor on reaction, for example, an alkylene oxide by means of tubular mixing and recycling this reaction liquid to the reactor thereby preventing increase in pressure of the reactor. An apparatus which comprises a reactor having a confined or open structure, a tubular mixer where a part of the reaction liquid drawn from the reactor is mixed with a gaseous starting material or a liquid starting material capable of being converted into vapor on reaction, which is blown through a nozzle, to cause a vapor-liquid reaction, and a liquid circulation pump for supplying the liquid drawn from the reactor to the tubular mixer and recycling the vapor-liquid reaction product to the reactor.