Patent ID: 7883042

Claim:
A crusher system, comprising: a first crushing surface and a second crushing surface which are operative to crush material between them; a hydraulic system which is operative to adjust a gap between the first crushing surface and the second crushing surface by adjusting a position of the first crushing surface with a hydraulic cylinder connected to the first crushing surface; the hydraulic system including a dump valve configured to dump hydraulic fluid from the hydraulic cylinder when the crusher system becomes overloaded; the hydraulic system including an accumulator connected to the hydraulic cylinder by a hydraulic liquid conduit; the accumulator including a hydraulic liquid chamber and a gas chamber separated from the hydraulic liquid chamber, the accumulator having a preloading pressure that is the pressure of the gas chamber when the hydraulic liquid chamber is empty, which is at least 0.3 MPa lower than a mean operating pressure of the hydraulic cylinder, such that the accumulator is active and synchronous variations occurring in the hydraulic pressure of the hydraulic cylinder during normal operation of the crusher system are attenuated by the accumulator.