Crank drive (reciprocating piston engine)
The crank mechanism used in reciprocating piston engines is referred to as the crank drive . In an engine with a reciprocating piston (e.g. internal combustion engine , steam - heat engine ) it is used to convert oscillating (reciprocating) into rotary (rotary) motion. In a working machine (. For example steam - engine , reciprocating piston pump ), it is vice versa.
The individual crankshaft parts in modern internal combustion engines (see figure on the left) are the crankshaft ( crank ), the connecting rod (push rod), the piston ( push member ) and the joints connecting them . The joints with the machine frame ( engine block ) are the crankshaft bearings and the sliding pairing of the sliding joint of the piston with the cylinder .
The items in steam engines and pumps have z. T. other names. Often a cross head (# 3 in the picture on the right) with a separate sliding joint is added as an extra part. This is firmly connected to the piston (# 1) via the piston rod (# 2), but keeps the transverse forces temporarily acting in connection with the connecting rod (push rod, # 4) away from it.