Abstract: A control device for an internal combustion engine including a camshaft of the internal combustion engine; a plurality of plane cam shape portions; at least one transitional shape portion; a cam switching mechanism; a cam position sensor; and a control section. The plane cam shape portions, at the camshaft, have valve lift characteristics different from each other, have respective cam faces parallel to a rotation axis of the camshaft, and are spaced apart from each other. The transitional shape portion is between two adjacent ones of the plane cam shape portions and has a curved cam face which connects the cam faces of the two plane cam shape portions. The cam switching mechanism switches between the valve lift characteristics for an intake valve by selecting one of the plane cam shape portions via the transitional shape portion.

Abstract: A control device for an internal combustion engine including a camshaft of the internal combustion engine; a plurality of plane cam shape portions; at least one transitional shape portion; a cam switching mechanism; a cam position sensor; and a control section. The plane cam shape portions, at the camshaft, have valve lift characteristics different from each other, have respective cam faces parallel to a rotation axis of the camshaft, and are spaced apart from each other. The transitional shape portion is between two adjacent ones of the plane cam shape portions and has a curved cam face which connects the cam faces of the two plane cam shape portions. The cam switching mechanism switches between the valve lift characteristics for an intake valve by selecting one of the plane cam shape portions via the transitional shape portion.

Abstract: A three-dimensional cam of a three-dimensional map state, having uncountable cam profiles continuously ranged along a rotation axis direction, and a valve lifter following a cam surface of the three-dimensional cam are included, and a lift characteristic of a valve is continuously controlled by relative motions of the three-dimensional cam and the valve lifter. The three-dimensional cam has cam top portions formed to have a smoothly ranged edge line substantially along the rotation axis direction thereof, and a part of the edge line includes at least one valley portion to take on a row of peaks. The cam peak portion of the cam top portion which forms the valley portion of the edge line is moderately set to be deviated toward a delayed side with reference to the rotation direction of the cam from the other cam peak portions.

Abstract: An engine unit includes a valve driving mechanism in which a cam having its cam profile axially varying continuously is slid along the axis of the cam shaft to control continuously a lift characteristic of an intake valve to be steplessly variable. In the control device of the engine, when the engine is, determined to be in a idling state by an idling-state determining unit, a target cam position is obtained according to a target valve lift amount calculated based on the cooling water temperature by a target cam position calculated unit, and the target cam position is corrected according to atmospheric pressure, an engine oil temperature, an ATF temperature, and an intake temperature, so that an engine rotation will be stabilized in the idling state.

Abstract: A three-dimensional cam of a three-dimensional map state, having uncountable cam profiles continuously ranged along a rotation axis direction, and a valve lifter following a cam surface of the three-dimensional cam are included, and a lift characteristic of a valve is continuously controlled by relative motions of the three-dimensional cam and the valve lifter. The three-dimensional cam has cam top portions formed to have a smoothly ranged edge line substantially along the rotation axis direction thereof, and a part of the edge line includes at least one valley portion to take on a row of peaks. The cam peak portion of the cam top portion which forms the valley portion of the edge line is moderately set to be deviated toward a delayed side with reference to the rotation direction of the cam from the other cam peak portions.

Abstract: An engine unit includes a valve driving mechanism in which a cam having its cam profile axially varying continuously is slid along the axis of the cam shaft to control continuously a lift characteristic of an intake valve to be steplessly variable. In the control device of the engine, when the engine is, determined to be in a idling state by an idling-state determining unit, a target cam position is obtained according to a target valve lift amount calculated based on the cooling water temperature by a target cam position calculated unit, and the target cam position is corrected according to atmospheric pressure, an engine oil temperature, an ATF temperature, and an intake temperature, so that an engine rotation will be stabilized in the idling state.