# Jaw crusher

➲  eccentric shaft

The eccentric shaft is a long, thick metal rod that runs through the center of the jaw crusher. It is attached to a rotating motor that drives the movement of the movable jaw, which is the part of the crusher that performs the actual crushing. As the motor turns, the eccentric shaft moves up and down, creating a reciprocating motion that causes the movable jaw to open and close, crushing the material between its jaws.