Abstract:
A variable valve timing mechanism-equipped engine is provided which allows a mount installing section and a hydraulic control valve of a variable valve timing mechanism to be positioned in a chain case without limitation of positioning of accessories such as a water pump, air conditioning compressor, power steering oil pump and alternator, and which simplifies an operating oil passage for the hydraulic control valve. In the variable valve timing mechanism-equipped engine, a mount installing section is positioned below an actuator cover section and is offset toward one side with respect to a cylinder axis, and intake- and exhaust-side hydraulic control valves are disposed sideward of the mount installing section with axes inclined toward a direction perpendicular to the crankshaft axis, the intake- and the exhaust-side hydraulic control valves overlapping one another.
Abstract:
Rotary valve system for controlling communication with a port in an internal combustion engine which, in one disclosed embodiment, has a crankshaft, compression and expansion pistons connected to the crankshaft for reciprocating movement within compression and expansion chambers, a combustion chamber in which air from the compression chamber is combined with fuel and burned to produce an increased gas volume. The valve system has an outer valve member which is rotatively mounted in a bore and has an opening which moves into and out of communication with the port as the outer valve member rotates, an inner valve member rotatably mounted within the outer valve member with an opening at least partly overlapping the opening in the outer valve member, a flange extending along one edge of the opening in the inner valve member and through the opening in the outer valve member for sealing engagement with the wall of the bore, and means for effecting rotation of the valve members to change the degree of overlap between the openings and thereby control the timing and duration of communication between the openings and the port.
Abstract:
To reduce seizing in a tensioner having a plunger slidable in a plunger-accommodating hole of a tensioner housing and biased in the projecting direction, the tensioner housing is formed of a hyper-eutectic Al—Si series alloy containing Si in the range from 14 to 16 weight % and having a particle diameter of proeutectic Si in the range from 20 to 30 μm.
Abstract:
In an internal combustion engine in which air-intake valves reciprocate in parallel to the direction of reciprocal motion of pistons, an air-intake structure of an internal combustion engine includes an outward projection of the air-intake port that is reduced to achieve a downsizing of a cylinder head. An air-intake structure includes air-intake valves that are supported by a cylinder head having integrally formed air-intake ports so as to reciprocate in parallel with the direction of reciprocal motion of the pistons. Fuel injection devices are formed integrally with a throttle body on intake manifolds to be connected to the air-intake ports. The air-intake ports extend toward the cylinder head cover along a recess formed on the outer surface of the cylinder head that is connected to the intake manifolds at positions just before reaching the identical plane to a mating surface between the cylinder head and the cylinder head cover.
Abstract:
In an internal combustion engine, a lubricated camshaft assembly is in a cam chamber formed between a cylinder head and a cylinder head cover. The cylinder head includes outer bolt-receiving holes in which selected head bolts are inserted, and which are outside of the cam chamber. An oil discharge passage in the cylinder head has an inlet opened into the cam chamber, and an outlet opened into an outer bolt-receiving hole. The inlet of the oil discharge passage is disposed on one lateral side of the cam chamber. An opening part of a timing chamber is on the other lateral side of the cam chamber. An endless loop timing chain or belt is disposed inside of the timing cover, for transmitting the power of a crankshaft to the camshaft. A vehicle, which may be a four-wheeled all-terrain vehicle, may incorporate the engine and cylinder head as described.
Abstract:
A variable valve apparatus for an internal combustion engine including a cylinder set comprising a plurality of cylinders. The variable valve apparatus includes: a control shaft adapted for rotation; a valve actuating mechanism provided for each cylinder of the cylinder set and adapted to vary a valve lift characteristic of an engine valve of the each cylinder of the cylinder set in accordance with a rotational position of the control shaft; and a valve lift adjusting mechanism provided for each cylinder of a first subset of the cylinder set and adapted to adjust the valve lift characteristic of the engine valve of the each cylinder of the first subset in accordance with a standard valve lift characteristic determined in accordance with the valve lift characteristic of the engine valve of each cylinder of a second subset of the cylinder set.
Abstract:
A valve timing control device includes a driving side rotational member synchronously rotatable with a crankshaft of an internal combustion engine, a driven side rotational member synchronously rotatable with a camshaft that controls an opening and closing operation of valves of the internal combustion engine, a retarded angle chamber, an advanced angle chamber, a fluid supply and discharge mechanism, a lock mechanism for locking the relative rotational phase at a predetermined lock phase, a phase displacement restriction mechanism switching the relative rotational phase between a restricted state and an unrestricted state, the phase displacement restriction mechanism includes a recess portion and an insertion member so as to achieve the restricted state and the unrestricted state, and a retention mechanism for retaining the phase displacement restriction mechanism in the unrestricted state in which the insertion member is retracted from the recess portion.
Abstract:
A multiple-cylinder DOHC engine, including a cylinder head block, a first camshaft that is mounted on the cylinder head block and is configured to drive one of an intake valve and an exhaust valve mounted on the cylinder head block, a second camshaft that is mounted on the cylinder head block and is configured to drive the other one of an intake valve and an exhaust valve, a camshaft drive system that is mounted at an end portion of the first camshaft in an axial direction thereof and is configured to drive the first camshaft, and a driving power transmission mechanism that is disposed at a center portion of the first and second camshafts in the axial direction to transmit a driving power from the first camshaft to the second camshaft.
Abstract:
A multicylinder internal combustion engine, which can simplify its control and is advantageous against thermal loads or vibrations includes a cylinder head with intake valves and exhaust valves arranged therein. Valve actuators are provided for openably operating the intake valves and exhaust valves, respectively. A cylinder head cover forms, in combination with the cylinder head, a valve actuator chamber with the valve actuators accommodated therein. At least some of the valve actuators are deactivatable to disable their corresponding cylinders. The multicylinder internal combustion engine is a V-shaped internal combustion engine provided with a front bank and rear bank. The cylinders on opposite ends in a direction of a crankshaft are set as full-time operating cylinders.
Abstract:
A synchronous drive apparatus includes first and a second rotors. The rotors have multiple teeth for engaging sections of an elongate drive structure. A rotary load assembly couples to the second rotor. The elongate drive structure engages about the rotors. The first rotor drives and the second rotor is driven by the elongate drive structure. One of the rotors has a non-circular profile having at least two protruding portions alternating with receding portions. The rotary load assembly presents a periodic fluctuating load torque when driven in rotation. The angular positions of the protruding and receding portions of the non-circular profile relative to the angular position of the second rotor, and the magnitude of the eccentricity of the non-circular profile, are such that the non-circular profile applies to the second rotor an opposing fluctuating corrective torque which reduces or cancels the fluctuating load torque of the rotary load assembly.