articulated con rod engine negre

A W12 engine is a twelve cylinder piston internal combustion engine in a W configuration. W12 engines have been manufactured in two distinct configurations. The original W12 configuration used three banks of four cylinders coupled to a common crankshaft, with 60° angles between the banks. These were used in several aircraft engine designs from the 1920s, notably the Napier Lion and various French engines. The more recent configuration, used in the Volkswagen Group W12, uses four rows of three cylinders merged into two 'cylinder banks' (two narrow-angle VR6 engine blocks), coupled to a common crankshaft.

In a reciprocating piston engine, the connecting rod or conrod connects the piston to the crank or crankshaft. Together with the crank, they form a simple mechanism that converts reciprocating motion into rotating motion.

Connecting rods may also convert rotating motion into reciprocating motion. Historically, before the development of engines, they were first used in this way.[1]

As a connecting rod is rigid, it may transmit either a push or a pull and so the rod may rotate the crank through both halves of a revolution, i.e. piston pushing and piston pulling. Earlier mechanisms, such as chains, could only pull. In a few two-stroke engines, the connecting rod is only required to push.[2]

Today, connecting rods are best known through their use in internal combustion piston engines, such as automotive engines. These are of a distinctly different design from earlier forms of connecting rods, used in steam engines and steam locomotives.