Patent ID: 7188600

Claim:
An internal combustion engine capable of selectively and temporarily disabling one or more cylinders during low-load operation thereof, said engine comprising a plurality of cylinders, at least some of said cylinders configured to be capable of selectively resting during engine operation, wherein said cylinders are divided into a plurality of cylinder groups, and each cylinder is provided with a throttle valve which is capable of being actuated in response to a throttle operation by a driver, wherein the engine further comprises a cylinder control unit for selecting cylinder groups to be operative or inoperative at a given time, according to at least a throttle operation, and a throttle valve control mechanism for each of said cylinder groups, which permits full closure of the throttle valves of the inoperative cylinders, and wherein each cylinder is provided with four or more valves, and each cylinder comprises at least one valve stop mechanism, the valve stop mechanism capable of transitioning a selected operable cylinder into a resting state by effecting an all-valve stop condition in which all of the valves of said selected cylinder are stopped, and wherein a partial valve stop operation can be conducted by stopping only some of the valves of the selected cylinder.