Abstract: In a variable timing mechanism, valve lifting characteristics are changed to meet the engine power output characteristics when the timing of valve operation is changed. The variable timing mechanism is provided for the side of at least one of an intake and an exhaust valve so that, when a running condition of an internal combustion engine is changed from a low engine speed to a high engine speed, a duration of valve opening of at least one of the intake and the exhaust valve is changed to increase an overlap period of the intake and the exhaust valve at the beginning of the changes in the running condition of the engine.

Abstract: A variable valve mechanism using a non-uniform coupling in an internal combustion engine is equipped with an axis-supporting member for supporting a cam-side rotation axis in an eccentric state. In the variable valve mechanism, the axis-supporting member is driven while taking account of friction occurring in the axis-supporting member by changing the position of the axis-supporting member so as to align with the direction of a dragging torque generated between the axis-supporting member and an intermediate rotating member or between the axis-supporting member and a rotation axis member.

Abstract: A hydraulic actuator is provided with a housing with an oil compartment formed therein; a power output shaft rotatably supported on the housing and extending out from an interior of the oil compartment to an exterior of the housing; a vane radially extending out from the power output shaft and maintained in contact with an inner wall of the oil compartment, whereby the vane divides the oil compartment into a first oil compartment and a second oil compartment; a first hydraulic pressure passage communicating the first oil compartment and a hydraulic pressure source with each other; a second hydraulic pressure passage communicating the second oil compartment and the hydraulic pressure source with each other; and an oil control valve regulating at least one of a first hydraulic pressure to be supplied to the first oil compartment through the first hydraulic pressure passage and a second hydraulic pressure to be supplied to the second oil compartment through the second hydraulic pressure passage.

Abstract: A variable valve driving mechanism is provided with an eccentric member (14) having an annular eccentric portion (15), which is eccentric relative to a camshaft (11), and arranged on an outer periphery of the camshaft (11); an intermediate rotating member (16) having a first groove portion (16A) and second groove portion (16B), which extend in radial directions, and rotatably supported on the eccentric portion (15); a cam lobe (12) having a cam portion (6) for opening and closing an intake valve or exhaust valve (2) and arranged concentrically with and rotatable around the camshaft (11) and for rotation relative to the camshaft (11); a first pin member (17,23) slidably fitted at one end thereof in the first groove portion (16A) and connected at opposite end thereof to the camshaft (11) so that rotation of the camshaft (11) is transmitted to the intermediate rotating member (16); a second pin member (18,24) slidably fitted at one end thereof in the second groove portion (16B) and connected at opposite end ther

Abstract: A cylinder liner or a cylinder block's bore portion formed of a composite alloy material reinforced with fibers and dispersed with ceramic particles. In the cylinder liner or the bore portion of the cylinder block, ceramic particles and alumina short fibers are uniformly dispersed in a light metal matrix. For producing the cylinder liner and the cylinder block, a preform having a shape identical with the cylinder liner or the bore portion is produced by mixing together the ceramic particles and the alumina short fibers. Molten light metal is infiltrated into voids of the preform during casting.

Abstract: A valve drive system of an internal combustion engine provided with a camshaft (20) adapted to be rotated by means of a crankshaft, a cam robe (38) rotatably mounted on the camshaft (20), a cam (24) formed integrally with the cam robe (38) and serving to open and close an intake valve (24) in cooperation with a valve spring (92), a viscous coupling (40) arranged between the camshaft (20) and the cam robe (38) and serving to transmit a rotatory force of the camshaft (20) to the cam robe (38), and a spiral spring (42) for connecting the camshaft (20) and the cam robe (38) and urging the cam robe (38) toward a predetermined rotational angle position with respect to the camshaft (20) .

Abstract: Intake ports are arranged independently from each other between an injector and each combustion chamber and are formed in an inverted triangular cross-sectional shape, whereby intake fluids flow along upper walls of the corresponding ports and become a stratified tumble flow in the combustion chamber 10. One of the three ports, said one port being centrally located and opposing a spark plug, is used as an air-fuel intake port, while the remaining ports arranged on both sides of the port are employed as air intake ports. A fuel injector is provided to feed fuel only to the port. An air-fuel mixture drawn into the combustion chamber through the port flows as a tumble flow. This tumble flow is flanked by tumble flows of air drawn into the combustion chamber through the ports respectively, whereby tumble flows flow in the form of a three-layer tumble swirl as a whole.

Abstract: A sealing assembly is adapted to be disposed between a stationary part and a rotary shaft in the stationary part so as to provide a seal in the gap between the stationary part and the rotary shaft. The sealing assembly has a slinger capable of rotating as a unit with the rotary shaft, and a rubber seal having a lip which makes a sliding contact with the slinger. The portion of the slinger contacted by the lip of the rubber seal is provided with apertures which allow a lubricating oil to flow into the region of the sliding contact between the lip of the seal rubber and the portion of the slinger.

Abstract: A sealing device is adapted to be disposed between a stationary part and a rotary shaft in the stationary part so as provide a seal in the gap between the stationary part and the rotary shaft. The sealing device has a slinger secured to one of the stationary part and the rotary shaft and a rubber seal secured to the other of the stationary part and the rotary shaft and provided with a lip which makes a resilient pressure contact with the slinger. When the rotation speed of the rotary shaft is increased, centrifugal force is increased to cause a tendency to decrease the pressure of contact between the lip and the slinger so that the wear of the lip is prevented to improve the durability of the sealing device. In addition, the resistance torque produced by the sealing device is not increased substantially even when the speed of rotation of the rotary shaft is increased.

Abstract: In a combustion chamber structure in a direct injection type diesel engine, in order to prevent flames from flowing out to a quench zone Q from a combustion chamber (32) which opens to a top part (30a) of a piston (30) to thereby prevent cooling of the flames and also in order to prevent a fuel spray from being concentrated on a lower portion of the combustion chamber (32), the fuel spray should be reflected in the combustion chamber (32) effectively according to displacement of the piston (30) to allow it to be mixed with air sufficiently in the combustion chamber (32) or in a cylinder (28), and to this end there are provided a guide wall (34) which becomes larger in inside diameter downwardly from an opening edge portion (33) of the combustion chamber (32), as well as fuel reflection walls (36, 38) which project below the guide wall (34) toward a central axis (lo) of the combustion chamber (32) and divide the combustion chamber vertically into a first combustion chamber (44) and a second combustion chamber

Abstract: In an alcohol engine using a alcohol and foreign fuel having combustibility higher than that of the alcohol as a fuel, an auxiliary fuel quantity adjusting means and control means are provided so that a ratio of a quantity of the foreign fuel to a quantity of the alcohol in the fuel to be supplied to the engine upon cold starting of the engine may be different from that upon warm-up of the engine.