Abstract: In a variable valve timing system for an internal combustion engine, a soft-landing revertive control that an electromagnetic brake is de-energized and then an angular position of a camshaft relative to a crankshaft returns to an initial position is performed by a combination of a feedback control and a feedforward control. During the revertive control, the feedback control is executed in such a manner as to temporarily halt the angular phase of the camshaft at a predetermined position, which is phase-changed by a predetermined phase angle from the initial position. After the feedback control, the operating mode is switched to a feedforward control, so as to return the angular phase of the camshaft from the predetermined position to the initial position by changing a controlled quantity or a control-signal duty cycle value for the electromagnetic brake with a predetermined time rate of change.

Abstract: In control apparatus and method for an internal combustion engine having variably operated engine valves, a target vacuum pressure is calculated on the basis of an engine driving condition and an opening angle of an electronically controlled throttle valve is disposed in an intake air passage to achieve the target vacuum pressure. A target air quantity to be sucked within an engine cylinder on the basis of the engine driving condition is calculated and a valve closure timing of an intake valve of, e.g., an electromagnetic operation type is controlled to achieve the target air quantity. At this time, in accordance with the target vacuum pressure TBOOST(or in accordance with an actual vacuum pressure BOOST detected by means of a vacuum pressure sensor), the target air quantity to calculate the valve closure timing of the intake valve calculated on the basis of target air quantity is corrected or the intake valve closure timing IVC per se is corrected by a correction value of &Dgr;IVC.

Abstract: In an internal combustion engine equipped with a pair of intake ports for each cylinder and capable of controlling a quantity of air entering the engine by controlling an intake valve open timing and an intake valve closure timing of each of a pair of intake valves located in the respective intake ports, a two-intake-valve operating mode is used in a high-load, high-speed operating range, whereas a one-intake-valve operating mode is used in predetermined low- and mid-load, low- and mid-speed operating ranges to create a great gas flow within the cylinder. A fuel injector is located in a first one of the intake ports to allow air flow through the first intake port over all operating ranges.

Abstract: A control system controls an intake air quantity to an engine by controlling an intake valve closing timing, instead of, or in cooperation with, a throttle valve. A controller estimates a quantity of internal EGR gases remaining in a cylinder, and controls the intake valve closing timing to a desired target timing determined in due consideration of the estimated internal EGR quantity. The estimated internal EGR quantity is a sum of a base quantity and an increase correction quantity determined in accordance with a valve overlap period, its middle angular position in crankshaft rotation and intake pressure. The target intake valve closing timing is determined in accordance with a target intake air quantity and the estimated internal EGR quantity.

Abstract: In an intake-air quantity control apparatus for an internal combustion engine with a variable valve timing system, an electronic engine control module has a microprocessor programmed to perform selecting one of a first control mode in which an intake-air quantity of the engine is controlled by adjusting the throttle opening, and a second control mode in which an intake-air quantity of the engine is controlled by adjusting the intake-valve closure timing. The microprocessor is programmed to perform a number of calculating and setting steps regarding the intake-air quantity and in-take valve closure timing.

Abstract: A control system for a variable displacement internal combustion engine determines effective flow cross sectional area as a predetermined function of a cross sectional area given against a throttle position. The effective flow cross sectional area is used to determine a volumetric airflow ratio. A control unit is connected with cylinder operator means for deactivating and reactivating at least some of engine cylinders and varying strokes in a cycle. The control unit modifies the predetermined function in response to the number of cylinders being activated and the number of strokes in a current cycle.

Abstract: Disclosed is a bit apparatus in which a cutter member having cutting teeth is axially supported on a shaft for rotation about the shaft, and a bearing mechanism is interposed between the cutter member and the shaft. The bearing mechanism includes at least a radial bearing for bearing a radially directed load and a thrust bearing for bearing an axially directed load. The radial bearing has a shaft-side split bearing member and a cutter-side split bearing member that are opposed to or in sliding contact with each other and capable of rotating relative to each other.

Abstract: A quantity of internal EGR gases remaining in an engine is estimated in accordance with an exhaust valve closing timing, an intake valve opening timing and an engine speed. The estimated internal EGR quantity is a sum of a base quantity and an increase correction quantity determined in accordance with a valve overlap period, its middle angular position in crankshaft rotation and intake pressure. The estimated internal EGR quantity is used for estimating an engine cylinder intake air quantity and for engine control such as ignition timing control, and intake air quantity control.

Abstract: A system and method control intake air of an internal combustion engine. The engine has at least one combustion chamber provided with intake valves together with an intake manifold provided with a throttle valve. The opening and closure timings of the intake valves are adjustable entirely independently by electromagnetic drivers from the crankshaft position to control the amount of intake air supplied to the combustion chamber. The system and method provide a response adjustment to variable valve timing control of the intake valves for unthrottled intake air control.

Abstract: In an internal combustion engine equipped with a pair of intake ports for each cylinder and capable of controlling a quantity of air entering the engine by controlling an intake valve open timing and an intake valve closure timing of each of a pair of intake valves located in the respective intake ports, a two-intake-valve operating mode is used in a high-load, high-speed operating range, whereas a one-intake-valve operating mode isused in predetermined low- and mid-load, low- and mid-speed operating ranges to create a great gas flow within the cylinder. A fuel injector is located in a first one of the intake ports to allow air flow through the first intake port over all operating ranges.

Abstract: A system and method control intake air of an internal combustion engine. The engine has at least one combustion chamber provided with intake valves together with an intake manifold provided with a throttle valve. The opening and closure timings of the intake valves are adjustable entirely independently by electromagnetic drivers from the crankshaft position to control the amount of intake air supplied to the combustion chamber. The system and method provide a response adjustment to variable valve timing and throttle valve position controls of the intake valves for unthrottled intake air control.

Abstract: An intake-air quantity control apparatus for an internal combustion engine with a variable valve timing system associated with an intake valve comprises an electronic control unit which controls an intake-air quantity of air entering an engine cylinder on the basis of an intake valve closure timing of the intake valve.

Abstract: A control unit controls both a motor actuated throttle valve and a magnetically actuated variable valve in accordance with an operation condition of an internal combustion engine. The control unit is configured to provide both a first control mode wherein an intake air control is carried out by controlling the open/close timing of the variable valve while keeping the throttle valve at a full-open or near full-open position and a second control mode wherein the intake air control is carried out by controlling the position of the throttle valve while reducing a controllable range of the open/close timing of the variable valve. The first and second control modes are selectively switched in accordance with the operation condition of the engine. The first and second control modes allow the engine to output the same engine torque under the same operation condition of the engine.

Abstract: In control apparatus and method for an internal combustion engine having variably operated engine valves, a target vacuum pressure is calculated on the basis of an engine driving condition and an opening angle of an electronically controlled throttle valve is disposed in an intake air passage to achieve the target vacuum pressure. A target air quantity to be sucked within an engine cylinder on the basis of the engine driving condition is calculated and a valve closure timing of an intake valve of, e.g., an electromagnetic operation type is controlled to achieve the target air quantity. At this time, in accordance with the target vacuum pressure TBOOST(or in accordance with an actual vacuum pressure BOOST detected by means of a vacuum pressure sensor), the target air quantity to calculate the valve closure timing of the intake valve calculated on the basis of target air quantity is corrected or the intake valve closure timing IVC per se is corrected by a correction value of AIVC.

Abstract: A control system controls an intake air quantity to an engine by controlling an intake valve closing timing, instead of, or in cooperation with, a throttle valve. A controller estimates a quantity of internal EGR gases remaining in a cylinder, and controls the intake valve closing timing to a desired target timing determined in due consideration of the estimated internal EGR quantity. The estimated internal EGR quantity is a sum of a base quantity and an increase correction quantity determined in accordance with a valve overlap period, its middle angular position in crankshaft rotation and intake pressure. The target intake valve closing timing is determined in accordance with a target intake air quantity and the estimated internal EGR quantity.

Abstract: A plurality of film holding units capable of respectively holding a plurality of kinds of films having different formats are provided. The plurality of film holding units are each constructed to be attachable to and detachable from a joint portion provided on an attachment connected to a video camera. Such an arrangement allows for providing an image capturing system and film holding units for use in the system, capable of dealing with the plurality of kinds of films having different formats.

Abstract: A system and method for unthrottled intake air control for an internal combustion engine. The engine has at least one combustion chamber provided with electromagnetic intake means. The opening and closing times of the intake means are adjustable entirely independently from the crankshaft position to control intake air supplied to the combustion chamber. A control unit is used to implement instructions for determining a first portion of requested intake airflow, which first portion requests a first engine response performance, and instructions for determining a second portion of requested intake airflow, which second portion requests a second engine response performance.

Abstract: A link establishing system according to the present invention is constituted by connecting between an upper device and a lower device a pair of optical transmission devices which have the same configuration and are connected with each other through an optical fiber. The optical transmission device is provided with an optical signal/electric signal converting circuit for determining an optical signal transmitted from a remote device as a receive signal, an optical signal detecting circuit for outputting an optical detection signal R1 indicating a result of detecting the receive signal, a byte-synchronous circuit for detecting a synchronous pattern from the receive signal and achieving byte-synchronism to output a synchronism establishment signal C1, and a link detecting circuit for detecting link establishment to output a link establishment signal L1 based on the signals R1 and C1.