Abstract:
A valve operating device that opens and closes a valve of an internal combustion engine by driving a valve stem in an axial direction includes a rocker cam that rocks in accordance with a rotation of a drive shaft and has a driving cam portion and a lift restricting cam portion; a cam follower that lifts the valve by contacting the driving cam portion slidingly; and a restricting member that prevents the cam follower from separating from the driving cam portion in cooperation with the lift restricting cam portion. A gap is formed between the restricting member and the rocker cam in a state where the cam follower is in contact with the driving cam portion and disappears such that the restricting member and the rocker cam come into contact with each other only when the cam follower separates from the driving cam portion.
Abstract:
An engine intake control apparatus for an engine that comprises at least one combustion chamber operatively connected to an intake port and an intake valve associated with each intake port, wherein the intake valve is adapted to open and close the intake port is disclosed herein. The intake control apparatus comprises a variable valve operating mechanism and a controller. The variable valve operating mechanism is configured and arranged to selectively change a valve closing timing and a valve lift amount of the intake valve. The controller is configured and arranged to control the variable valve operating mechanism when the engine is in a low load condition. The valve closing timing is determined such that an actual compression ratio of the engine is reduced relative to the actual compression ratio when the engine is operating in a high load condition. The valve lift amount is smaller when the engine is in the low load condition relative to the valve lift amount when the engine is in the high load condition. A method for controller an engine is also disclosed.
Abstract:
An internal combustion engine includes a piston reciprocating in a cylinder; a crankshaft; and a multilink piston-crank mechanism linking the piston with the crankshaft. The multilink piston-crank mechanism includes an upper link having a first end connected with the piston by a piston pin; a lower link mounted rotatably on a crankpin of the crankshaft and having a first end connected with a second end of the upper link by a first connection pin; a control link having a first end connected with a second end of the lower link by a second connection pin; a control shaft connected movably with a second end of the control link and configured to rotate in synchronization with the crankshaft and at a half rotational speed of the crankshaft; and a phase adjusting section configured to variably adjust a phase of rotation of the control shaft relative to the crankshaft in accordance with an operating condition of the engine. The multilink piston-crank mechanism is configured to variably control a piston stroke characteristic of the engine.
Abstract:
A link mechanism usable for a variable compression ratio mechanism of an internal combustion engine includes first and second links pivotally connected by a pin inserted through cylindrical first and second pin boss portions of the first and second links. Each of the first and second pin boss portions includes a circumferentially extending first narrow section, and a circumferentially extending first wide section having an axial wall thickness greater than the axial wall thickness of the first narrow section. The wide sections of the first and second pin boss portions are overlapped in an region extending in the axial direction of the pin.
Abstract:
A control apparatus for an internal combustion engine includes a variable compression ratio mechanism capable of varying a compression ratio of the engine, a compression ratio setting section that sets a compression ratio to be attained by the variable compression ratio mechanism in accordance with an operating condition of the engine, a knock detecting section that detects a knock occurrence state, an ignition timing learning correcting section that determines a learning correction value of an ignition timing in accordance with the knock occurrence sate, and a compression ratio correcting section that corrects the compression ratio set by the compression ratio setting section in accordance with the learning correction value of the ignition timing. A control method is also provided.
Abstract:
There is provided a system for controlling an intake valve of an internal combustion engine, including a variable valve mechanism having a control shaft to continuously vary a valve lift amount of the intake valve according to a rotational angle of the control shaft and an actuator to drive the control shaft, and a control unit that controls the actuator so as to set the control shaft to a first rotational angle position at which the valve lift amount takes a first value during an engine idling period and to a second rotational angle position at which the valve lift amount takes on a second value larger than the first value to provide a required intake quantity to start the engine during a time from the beginning of an engine speed decrease period, through an engine stop period, until the completion of a cranking period of the engine.
Abstract:
In a VVA apparatus, when an actual lift amount detected by a lift-amount detecting sensor exceeds a basic lift-amount target value by a predetermined value or more, ECU corrects a lift phase through a lift-phase varying mechanism to separate from a piston TDC with respect to a basic lift-phase target value.
Abstract:
A paired counterweights of a crankshaft have projected inner surfaces which protrude toward each other defining a given space therebetween. A plurality of links are arranged to convert a reciprocating motion of a piston to a rotational motion of the crankshaft. One of the links is pivotally connected to other links through link connecting portions and swingably disposed on a crank pin of the crankshaft so that upon rotation of the crankshaft, a peripheral portion of the link passes through the given space. At least one of the link connecting portions is placed within an imaginary circle which would be described by a radially innermost part of the projected inner surfaces of the paired counterweights when the paired counterweights turn about an axis of the crank pin.
Abstract:
An internal combustion engine has an intake valve control device for controlling at least intake valves. The control device comprises a first mechanism which varies a working angle of the intake valve; a second mechanism which varies an operation phase of the intake valve; and a control unit which controls both the first and second mechanisms in accordance with an operation condition of the engine. The control unit is configured to carry out controlling variation in the open timing of the intake valve effected by the first mechanism to be larger than variation in the open timing of the intake valve effected by the second mechanism.
Abstract:
Parameters which are related to the rate at which particulate matter accumulates and is reburnt, are monitored and the time at which a regeneration is required and/or the length of time a regeneration should be induced, are derived based on the same. The temperature at the inlet and outlet of a trap in which particulate matter is accumulated are monitored and measures such as throttling the induction and exhaust are implement in addition to energizing a heater disposed immediately upstream of the trap as required in order to elevate the trap temperature and to induce and maintain the reburning during a trap regeneration. The pressure differential across the trap can be used to determine the amount of incombustible matter (ash) which has accumulated in the trap and to modify the regeneration timing. When the temperature of the exhaust gases cannot be raised sufficiently, a by-pass is opened to attenuate cooling of the trap by the low temperature gases.