Crankshaft

The purpose of the crankshaft is to take the force from the connecting rod and convert it into torque which is output through the crankshaft and drives the other accessories on the engine to work. The crankshaft is subjected to the combined action of the centrifugal force of the rotating mass, the gas inertia force of the periodic change and the reciprocating inertia force, so that the crankshaft bears the action of the bending and torsional load. The crankshaft is required to have enough strength and stiffness, and the surface of the journal needs to wear resistance, uniform work and good balance. In order to reduce the mass of the crankshaft and the centrifugal force generated during movement, the crankshaft journal is often made hollow. Oil holes are cut on each journal surface to introduce or draw oil to lubricate the journal surface. In order to reduce stress concentration, the connection of the spindle neck, the crank pin and the crank arm are connected by a transition arc.