Camshaft

A camshaft is a shaft to which a cam is fastened or of which a cam forms an integral part. A camshaft is a shaft to which a cam is fastened or of which a cam forms an integral part. The camshaft was described in Turkey (Diyarbakır) by Al-Jazari in 1206. He employed it as part of his automata, water-raising machines, and water clocks such as the castle clock. The camshaft later appeared in European mechanisms from the 14th century. Among the first cars to utilize engines with single overhead camshafts were the Maudslay designed by Alexander Craig and introduced in 1902 and the Marr Auto Car designed by Michigan native Walter Lorenzo Marr in 1903. In internal combustion engines with pistons, the camshaft is used to operate poppet valves. It consists of a cylindrical rod running the length of the cylinder bank with a number of oblong lobes protruding from it, one for each valve. The cam lobes force the valves open by pressing on the valve, or on some intermediate mechanism, as they rotate.