Patent ID: 8632028
Filing Date: 2014-01-21
Classification: B02C

Abstract:
1. A roller press comprising: a frame; a first roller attached to the frame; a second roller positioned adjacent to the first roller such that a nip is formed between the first and second rollers; the first and second rollers being rotatable to comminute material that passes through the nip; a fluid circuit comprising a first cylinder moveably attaching the second roller to the frame, a first primary accumulator, and a first secondary accumulator which is isolated from the first cylinder and first primary accumulator until an uncrushable element passes through the nip; the first secondary accumulator being kept at a pressure greater than the first cylinder and the first primary accumulator the first cylinder having a moveable element attached to the second roller and a fluid, the fluid being moveable to move the moveable element for adjusting a position of the second roller relative to the first roller; the first primary accumulator being connected to the first cylinder such that at least a portion of the fluid is moveable from the first cylinder to the first primary accumulator when the first and second rollers are rotated to comminute crushable material; the first secondary accumulator also being connected to the first cylinder; the fluid circuit further comprising a second cylinder, a second primary accumulator, and a second secondary accumulator; the second secondary accumulator being kept at a pressure greater than the second cylinder and the second primary accumulator; the second secondary accumulator being isolated from the second cylinder and second primary accumulator in the absence of an uncrushable element; the second primary accumulator being connected to the second cylinder such that at least a portion of the fluid in the second cylinder is moveable from the second cylinder to the second primary accumulator; the second secondary accumulator also being connected to the second cylinder; wherein the second roller is configured to move away from the first roller when fluid moves from the first cylinder to the first secondary accumulator to widen the nip and the second roller is configured to be movable toward the first roller to narrow the nip; and, wherein fluid is not moved from the first cylinder to the first secondary accumulator when the crushable material is being comminuted and an uncrushable element is not passing through the nip.