Abstract: A multi-valve internal combustion engine having a plurality of valves having skewed axes that are operated by cam lobes of a single cam shaft. The cam shaft operates the valves through rocker arms each of which are pivoted independently about axes that are skewed relative to the cam shaft axis so as to minimize bending stresses on the valve during its actuation. This also avoids scuffing between the rocker and the valve stem. At the same time, good contact is maintained between the cam lobe and the follower surface by machining the cam lobe so that it will have a slight concavity at least in its tip portion so as to ensure constant line contact with the follower.

Abstract: A power source system 402 for electric motor-operated vehicles adapted to determine an actual capacity of a chargeable battery 400, namely the maximum capacity learning value at the current time point after it is used in cycles, comprises; a discharge means 403 for performing refreshment discharge of the chargeable battery 400, a charge control means 404 for controlling the discharge means 403 to perform the refreshment discharge with a discharge current including a pulse waveform portion, and an actual capacity learning means 405 for learning the actual capacity of the chargeable battery 400 on the basis of discharge capacity including the discharge capacity at the time of refreshment with the pulse waveform current.