Abstract: A flexible vertical grinder, having a main shaft mounting frame (4) on a grinder frame (1); a main shaft (3) is mounted on the main shaft mounting frame; a stelliform bracket (9) is mounted on the main shaft; a hammer wheel grinder and a material-sorting balance wheel device are mounted on the stelliform bracket; the material-sorting balance wheel (4) and the hammer wheel (17) are on the same horizontal plane. The vertical grinder can apply different grinding forces according to different specific surface areas of the to-be-ground material, and can grind materials of different grades properly but not excessively, thus greatly improving crushing efficiency, having good overall rigidity and stable operation, and facilitating maintenance.

Abstract: A method to reduce the integral non-linearity (INL) of a digital-to-analog converter (DAC) and a DAC implementing said method are disclosed. The method in this invention is a pseudo dynamic element matching (PDEM) method. Compared with a prior art, the method of this invention provides a better performance in glitch. Compared with another prior art, the method of this invention also guarantees that DEM will not fail even if the input digital code remains constant.

Abstract: The roller mill according to the invention substantially comprises at least one grinding roller and a grinding table, the grinding table having a grinding table inner space which is open in a downward direction, at least one grinding roller drive system for driving the grinding roller and a grinding table drive system for driving the grinding table. The grinding table drive system further has a gearless direct drive which is arranged in the grinding table inner space.

Abstract: A high efficiency bowl mill (100) is provided by the present invention. Included in the high efficiency bowl mill (100) is a plow (185) that is downstream of a grinding roll (180) on a grinding surface (145). The plow (185) loosens material that has been compacted by the grinding roll (180). Also included is a deflector (165) that redirects an air stream so as to pick up material loosened by the plow (185) and deposit material requiring further grinding. An outlet (201) of an inverted cone (200) is positioned so as to deposit material for pulverization on the grinding surface (145) and to restrict the air stream from entering the inverted cone (200).

Abstract: A bowl mill for a coal pulverizer with an air mill for primary entry of air, comprising a substantially closed separator body (2) having a central axis; and a bowl-like grinding table (3) mounted on a shaft (4) rotatable about said central axis, cooperating with a plurality of grinding rolls (6). The airmill is provided with multiple entry openings (17?, 17?; 18?, 18?; 21, 25) on the outer wall of the air mill for multiple entry of hot primary air from the inlets, resulting in better uniformity in air flow around the air mill section and for minimizing formation of eddies and vortices As a variation of the multiple entry double entry openings can be arranged for entry of hot primary air.

Abstract: A system for use with a roll bowl type mill for the pulverizing of solid fuels such as coal. The system includes hardware in the form of sensors and other components and software to among other things monitor the operating condition of the mill's moving parts and predict their failure. The system can determine the diameter of the mill's rollers, or the reduction and/or depth of cup wear of each of the rollers, the thickness of the solid fuel in the mill, can by analysis determine the wear of each of the one or more roller bearings in the mill and predict their failure and can estimate the mill availability.

Abstract: An accumulator assembly comprising at least two accumulators that are hydraulically interconnected to the same source of hydraulic fluid. Each accumulator containing an energy absorbing medium which is compressible when a movable barrier which separates the hydraulic fluid from the energy absorbing medium is acted upon by an increase in pressure of the hydraulic fluid. When the assembly contains two accumulators, one accumulator contains a compressibility limiter which interrupts the compressibility of the energy absorbing medium within the accumulator and the other accumulators does not contain a compressibility limiter so that the energy absorbing media therein may be fully compressed by the hydraulic fluid. The accumulator assembly is favorably utilized in a vertical roller mill.

Abstract: Graphite particles having a bent laminate structure inside each particle are produced by feeding, into an impact grinder, graphite particles having an average particle diameter of 5 mm or less together with a gas current to apply an impact to the graphite particles to form, by a compression force, a bent laminate structure inside each graphite particle. The resulting graphite particles have an average particle diameter of 100 &mgr;m or less, are low in anisotropy, have a nearly spherical shape, and are highly crystalline.

Abstract: A process for producing a coal-water slurry of low viscosity and high coal concentration with a low specific energy and a good efficiency is provided, which process comprises wet-grinding coal by means of a wet vertical ring-roll mill in the presence or absence of a surfactant and recycling a part of the coal ground by the mill, as it is, without classifying it, to the mill through a splitter.

Abstract: An apparatus is provided for pulverizing material into comminuted particles in which at least three rollers are mounted for rotation and maintained in contact with the material on a grinding ring. The rollers are suspended in a manner to allow the rollers to swivel about respective vertical axes perpendicular to their respective axes of rotation.

Abstract: A press roll for acting in opposition to a counter roll. The press roll has a support member which is supported at its opposite ends. The support member is stationary in certain most embodiments and rotatable in one embodiment. A flexible, liquid-tight endless press jacket is wrapped around the support member. At each lateral end of the press roll, the press jacket is fastened to the outward end of a supporting disk, which is rotatably mounted on the support member. The lateral edge zones of the press jacket are both deformed radially inwardly around the outside of the respective supporting disks and each edge zone is clamped there by a annular clamping flange. To facilitate deformation of the edge zones, at least one of the edge zones terminates in a series of tongues separated by cutouts arrayed around the roll. Coiled tension springs engage the edge zone and/or the tongues to pull them in the direction toward the axis of the roll.