Patent ID: 7578272
Filing Date: 2009-08-25
Classification: F01L,F02D,Y02T,Y10T

Abstract:
1. A multiple cylinder engine comprising: plurality of cylinders, each cylinder including a valve configured to open and close a port associated with each of the respective cylinders, the cylinders comprising at least a first cylinder group and a second cylinder group; a drive shaft configured to rotate about an axis; a plurality of valve actuators configured to transmit rotational movement of the drive shaft to the valves; a change mechanism comprising a control member that is configured to change a transmission state of the rotational movement transmitted from the drive shaft to the valve actuators, the change mechanism configured to sequentially change an open period and a largest lift amount of each valve by changing a control amount of the control member; wherein the control member is common to the first and second cylinder groups and wherein the transmission states for the first cylinder group differ from the transmission states of the second cylinder group in accordance with the control amount of the control member, and the valve open period and the largest lift amount of the valves in the first cylinder group is capable of being set to zero in a predetermined operational range to suspend operation of the first cylinder group; wherein the drive shaft includes a camshaft driven by a crankshaft; the valve actuator includes a rocker arm supported for swing movement; the change mechanism includes a swing cam supported for swing movement to follow the camshaft, and a control arm positioned between the swing cam and the camshaft or the rocker arm and supported by the control member for swing movement, the control amount of the control member is varied to change a relative relationship between a position of control arm and a position of the camshaft or a position of swing cam so as to sequentially change the open period and the largest lift amount of the valve; and wherein a cam surface of the swing cam has a shape which differs between the first and second cylinder groups, the cam surface of the swing cam for the first cylinder group is configured to bring a valve lift amount to zero when the control amount of the control member is in the predetermined range.