Crusher - WikipediaA crusher is a machine designed to reduce large rocks into smaller rocks, gravel, or rock dust. .. A jaw crusher uses compressive force for breaking of particle. .. The electric motor of the cone crusher drives the eccentric shaft to make periodic.primary crusher make,Crushing for particle shape - Aggregates ManagerNov 17, 2014 . The main job of the primary crusher is to reduce the particle size, with . “Some form of rock-on-rock crushing is usually required to make a.