The camshaft, a shaft to which cams are attached, was first introduced in 1206 by al-Jazari, who employed them in his automata, Water clocks (such as the candle clock) and water-raising machines.The cam and camshaft later appeared in European mechanisms from the 14th century.
The eccentrically mounted handle of the rotary quernstone in the fifth century BCE Spain that spread across the Roman Empire constitutes a crank. The earliest evidence of a crank and connecting rod mechanism dates to the 3rd century AD Hierapolis sawmill in the Roman Empire. The crank also appears in the mid-9th century in several of the hydraulic devices described by the Banū Mūsā brothers in their Book of Ingenious Devices.
In 1206, al-Jazari invented an early crankshaft, which he incorporated with a crank-connecting rod mechanism in his twin-cylinder pump. Like the modern crankshaft, al-Jazari’s mechanism consisted of a wheel setting several crankpins into motion, with the wheel’s motion being circular and the pins moving back-and-forth in a straight line.The crankshaft described by al-Jazari transforms continuous rotary motion into a linear reciprocating motion and is central to modern types of machinery such as the steam engine, internal combustion engine, and automatic controls.
He used the crankshaft with a connecting rod in two of his water-raising machines: the crank-driven chain pump and the double-action reciprocating piston suction pump. His water pump also employed the first known crank-slider mechanism.