| 摘要 |
An internal combustion engine has n member of cylinders, a piston in each cylinder connected to a crankshaft (2), each piston being in phase or out of phase with the others by A DEG or a multiple thereof (A=720/n), cams for actuating inlet and exhaust valves to each cylinder, and a cam drive mechanism (5) which rotates the cams in phased relationship with the crankshaft (2) to open the valves in sequence for a desired angle of rotation of the crankshaft. The cam drive mechanism also includes means for combining the rotational movement of the cams with a phased oscillatory movement of the camshaft (3) and cams of variable amplitude about the axis of rotation at a frequency f times the crankshaft frequency so that over the period which the valves are opened and/or their timings variable, f has the following values: f=2n when the number of cylinders n=1; f=n or n/2 when n=2; and f=n/2 when n=3 or more. The selection of the frequency of the oscillations allows all the cams to be mounted on the same camshaft. |
