Patent ID: 8583322

Claim:
A mobile crusher comprising: a crusher that crushes raw material; a discharge conveyor being disposed on a downstream side of the crusher to discharge the material crushed by the crusher; an engine that serves as a driving source at least for the crusher and the discharge conveyor; an engine controlling unit that controls a speed of the engine; a load change rate determining unit that determines a rate of change in a load on the crusher; and a crushed material determining unit that determines presence or absence of the crushed material on the discharge conveyor, wherein the load change rate determining unit is configured to determine that the load on the crusher is reduced based on a negative determined rate of change in the load on the crusher, and when the load change rate determining unit determines that the load on the crusher is reduced and the crushed material determining unit determines that the crushed material is not present on the discharge conveyor, the engine controlling unit lowers the speed of the engine to a decelerated speed.