Abstract: With a variable valve timing system, engine operability may be lost when performing open control of lift characteristic amounts to the minimum or the maximum of a variable range when a sensor error occurs. The present invention provides a lift operation angle changing mechanism that can continuously change intake valve lift amount and operation angle within a prescribed variable range. A target operation angle is calculated based on the number of engine revolutions and the accelerator pedal opening APO. An error is determined for the operation angle sensor that detects the actual operation angle. A normal control amount is calculated based on the target operation angle and the actual operation angle, and a failure control amount is calculated based on the number of engine revolutions. Therefore, an intermediate value within the variable range can be obtained as the failure control amount.

Abstract: In an internal combustion engine, a starter motor is energized in response to a request for an engine start to perform a cranking of the internal combustion engine. Thereafter, an electric variable valve motor is energized to control a valve opening/closing characteristic to a condition designed to promote the cranking. The start of the energization of the electric variable valve motor is delayed from the start of the energization of the starter motor at least by a predetermined delay period.

Abstract: An intake system for an internal combustion engine is provided which comprises a variable valve control apparatus capable of variably and continuously controlling the amount of intake air of an internal combustion engine by varying valve lift characteristics of an intake valve, a collector fluidly connected with a plurality of intake passages for cylinders of the internal combustion engine, and a pressure control mechanism for producing within the collector a vacuum that increases with increase of one of the amount of intake air, engine speed and engine load of the internal combustion engine.

Abstract: With a variable valve timing system, engine operability may be lost when performing open control of lift characteristic amounts to the minimum or the maximum of a variable range when a sensor error occurs. The present invention provides a lift operation angle changing mechanism that can continuously change intake valve lift amount and operation angle within a prescribed variable range. At B11, the target operation angle is calculated based on the number of engine revolutions and the accelerator pedal opening APO. At B12, an error is determined for the operation angle sensor that detects the actual operation angle. At B13, the normal control amount is calculated based on the target operation angle and the actual operation angle. At B14, the failure control amount is calculated based on the number of engine revolutions. Therefore, an intermediate value within the variable range can be obtained as the failure control amount.

Abstract: A variable compression ratio system for an internal combustion engine, including a variable compression ratio mechanism for continuously varying a compression ratio of the engine, the variable compression ratio mechanism including a control shaft rotatably moveable to a rotational position corresponding to the compression ratio, a hydraulic actuator driving the control shaft to the rotational position depending on operating conditions of the engine, a hydraulic pressure source mechanically driven by the engine to produce a hydraulic pressure supplied to the hydraulic actuator, and a hydraulic control for variably controlling the hydraulic pressure supplied to the hydraulic actuator on the basis of the engine operating conditions.

Abstract: A learning apparatus for a variable valve control of an internal combustion engine includes a variable valve operating mechanism, an actuator that rotationally drives the control shaft, a control shaft sensor that detects an angular position of the control shaft, a reference position determining section that determines whether or not the control shaft has reached a predetermined reference position under the drive from the actuator, a learning section that learns an output value of the control shaft sensor when it is determined that the control shaft has reached the reference position and stores the learned output value as a sensor output reference value, and a learning preparing section that causes the control shaft to be driven by the actuator toward the reference position when a crankshaft of the engine is rotating and supply of fuel to the engine is stopped. A learning method is also provided.

Abstract: A variable valve control system for an internal combustion engine includes first and second variable valve control mechanisms capable of varying valve lift characteristics of one of an intake valve and exhaust valve, and a controller that controls the first and second variable valve control mechanisms. The controller includes a detecting section for detecting a malfunction of the first variable valve control mechanism, and a control section that controls the second variable valve control mechanism upon detection of the malfunction of the first variable valve control mechanism so that an intake valve opening timing coincides with or is retarded from an exhaust valve closing timing. A variable valve control method is also provided.

Abstract: A variable valve control system for an internal combustion engine including a plurality of cylinders, the variable valve control system including a variable lift characteristic control mechanism to adjust a valve lift characteristic of each of intake valves.

Abstract: A learning apparatus for a variable valve control of an internal combustion engine includes a variable valve operating mechanism, an actuator that rotationally drives the control shaft, a control shaft sensor that detects an angular position of the control shaft, a reference position determining section that determines whether or not the control shaft has reached a predetermined reference position under the drive from the actuator, a learning section that learns an output value of the control shaft sensor when it is determined that the control shaft has reached the reference position and stores the learned output value as a sensor output reference value, and a learning preparing section that causes the control shaft to be driven by the actuator toward the reference position when a crankshaft of the engine is rotating and supply of fuel to the engine is stopped.

Abstract: A variable valve control system for an internal combustion engine including a plurality of cylinders, the variable valve control system including a variable lift characteristic control mechanism to adjust a valve lift characteristic of each of intake valves.

Abstract: In an internal combustion engine, a starter motor is energized in response to a request for an engine start to perform a cranking of the internal combustion engine. Thereafter, an electric variable valve motor is energized to control a valve opening/closing characteristic to a condition designed to promote the cranking. The start of the energization of the electric variable valve motor is delayed from the start of the energization of the starter motor at least by a predetermined delay period.

Abstract: A collector equipped intake system of an internal combustion engine, the collector is fixedly connected directly to either of a cylinder-head side wall and a collector mounting bracket hermetically covering perimeters of intake-port opening end portions of a plurality of intake ports opening through the side wall. A plurality of intake-manifold branches respectively communicating with the plurality of intake ports, are protruded into the interior space of the collector.

Abstract: A control system for an internal combustion engine having a variable valve operating mechanism capable of varying at least one of a valve lift and an operation angle of an engine valve continuously is provided. The control system comprises a detecting device that detects an operating condition of the variable valve operating mechanism and produces a signal representative thereof, and a controller that controls the operating condition of the variable valve operating mechanism in response to the signal from the detecting device. The controller is programmed to determine whether an operation responsiveness of the variable valve operating mechanism is lowered based on the signal from the detecting device and vary operational characteristics of the variable valve operating mechanism when the operation responsiveness of the variable valve operating mechanism is lowered. A control method is also provided.

Abstract: A variable valve control system for an internal combustion engine includes first and second variable valve control mechanisms capable of varying valve lift characteristics of one of an intake valve and exhaust valve, and a controller that controls the first and second variable valve control mechanisms. The controller includes a detecting section for detecting a malfunction of the first variable valve control mechanism, and a control section that controls the second variable valve control mechanism upon detection of the malfunction of the first variable valve control mechanism so that an intake valve opening timing coincides with or is retarded from an exhaust valve closing timing. A variable valve control method is also provided.

Abstract: A control system of an internal combustion engine is comprised of an operation angle adjustment mechanism which continuously varies an operation angle of intake valves of the engine, an air-fuel ratio detector which detects an exhaust parameter indicative of air-fuel ratio information, and a control unit which are coupled to the operation angle adjustment mechanism and the air-fuel ratio detector. The control unit feedback-controls an air-fuel ratio of the engine on the basis of the exhaust parameter and corrects the operation angle on the basis of the exhaust parameter.

Abstract: A variable compression ratio system for an internal combustion engine, including a variable compression ratio mechanism for continuously varying a compression ratio of the engine, the variable compression ratio mechanism including a control shaft rotatably moveable to a rotational position corresponding to the compression ratio, a hydraulic actuator driving the control shaft to the rotational position depending on operating conditions of the engine, a hydraulic pressure source mechanically driven by the engine to produce a hydraulic pressure supplied to the hydraulic actuator, and a hydraulic control for variably controlling the hydraulic pressure supplied to the hydraulic actuator on the basis of the engine operating conditions.

Abstract: In an engine capable of continuously controlling an intake air quantity by varying an intake valve operating characteristic, an intake valve lift is sensed as well as an engine speed. Then, an intake air quantity is calculated in accordance with the engine speed and intake valve lift when an engine operating point is in a very low lift state.

Abstract: An internal combustion engine comprises a variable valve control device that varies a lift degree of an intake valve, an air intake passage led to an intake port of the engine that is incorporated with the intake valve and a fuel injection valve arranged to inject fuel into the intake port. The fuel injection valve has a first injection mode wherein each fuel injection shot is entirely carried out during opening period of the intake valve and a second injection mode wherein each fuel injection shot entirely finishes prior to opening action of the intake valve. A control unit is further employed by the engine, which allows the fuel injection valve to select one of the first and second injection modes in accordance with the lift degree of intake valve effected by the variable valve control device.

Abstract: Intake valve drive shaft and exhaust valve drive shaft are arranged in parallel to each other and provided with sprockets, respectively, for receiving engine rotation from a crank shaft. A rocker cam is swingably mounted on the intake valve drive shaft to push the intake valve, and connected mechanically by a link mechanism with the intake valve drive shaft. The axis of the intake valve drive shaft is offset from the axis of the intake valve to one side. The rocker cam includes a cam nose which projects to the other side of the axis of the intake valve when the intake valve is in the closed state.

Abstract: In an internal combustion engine employing a variable lift and working angle control mechanism and a variable phase control mechanism, a first sensor is provided to detect an actual control state of the variable lift and working angle control mechanism every sampling time intervals. Also provided is a second sensor that detects an actual control state of the variable phase control mechanism every sampling time intervals. At least one of the sampling time interval for the first sensor and the sampling time interval for the second sensor has a characteristic that the one sampling time interval varies relative to the engine speed. A rate of change in the sampling time interval for the first sensor with respect to the engine speed is different from a rate of change in the sampling time interval for the second sensor with respect to the engine speed.