Abstract: A grinding mill having a rotatable grinding chamber within which is a body of elongate grinding members that have a longitudinal axis substantially longer than the maximum transverse dimension thereof. The mill is arranged in such a way as to retaining the grinding member axes substantially parallel to the grinding chamber rotational axis. The grinding members have a cross-sectional shape and a sufficient exterior surface smoothness for enabling a body of such members to tumble over and against one another in a rotating grinding chamber and to grind particulate material within the body, as well as a ratio of mass per unit of length which varies from one position to another along the length of the longitudinal axis.

Abstract: Apparatus for reducing and sizing particle material that is readily susceptible to efficiency enhancement with vibratory exciters. The apparatus includes a rotary drum particle size reductino device having a substantially imperforate drum, and a rotary screen having a perforate screening member with upstream and downstream portions, said upstream portion of the screen surrounding at least a portion of the periphery of the drum. A screen supporting member including a vibratory exciter engages an upstream portion of the screen for vibrating said upstream portion substantially independently of the drum.

Abstract: A gyratory crusher of the type including a frame with a bowl mounted on the frame and a head cooperable with the bowl in crushing operations. The head is rotatably mounted on an eccentric which is driven through suitable gearing. The head is positively rotated by a drive means either independent of or integral with the drive for the eccentric. The bowl is free to rotate about the frame. The rotary motion imparted to the head serves to induce centrifugal force to the particles of material within the crushing chamber. This centrifugal force, when combined with the gravitational force acting on the particles of material, results in the material moving through the crushing chamber in a trajectory which follows the configuration of the crushing chamber.

Abstract: A method of operating a rotor-equipped breaker/crusher for coal and other material in which the drum is rotated at close to critical speed, and in which lifter shelves in the drum are adjusted for dropping material into the path of the rotor at a point where the rotor not only fragments the material, but also emphasizes the flinging of the material against the downwardly moving perforated wall of the drum. Methods of this character enable a relatively small breaker/crusher to effectively duplicate the performance of much larger existing units, while successfully controlling the production of fines.

Abstract: A material reducer for coal, lignite, ore, stone, rock, oil shale and the like which employs rotary hammers, bars or the like not only to crush the material but also to propel the crushed material upwardly along a confined or partially confined path which discharges for example onto an output conveyor or directly to a screen or other processing equipment. The feed-in or input end of the crusher can be at a level sufficiently low to be supplied by the newer more mobile loading units such as front-end loaders, over-the-head loaders, and others. The center of gravity can also be substantially lowered, providing more stability without the normal cumbersome frame and support structure.

Abstract: A material reducer for coal, lignite, ore, stone, rock, oil shale and the like which employs rotary hammers, bars or the like not only to crush the material but also to propel the crushed material upwardly along a confined or partially confined path or discharge chute which empties onto an output conveyor, a screen or other processing equipment. The chute is provided with means to reduce or eliminate clogging at the discharge port from the reducer. The input end of the reducer can be at a level sufficiently low to be supplied by mobile loading units such as front-end loaders, over-the-head loaders, and others. The center of gravity can also be substantially lowered, providing more stability without the normal cumbersome frame and support structure.

Abstract: A rotor-equipped breaker/crusher drum for coal and other material in which means are provided for rotating the drum at close to critical speed, and in which lifter shelves in the drum are adjusted for dropping material into the path of the rotor at a point where the rotor not only fragments the material, but also emphasizes the flinging of the material against the downwardly moving perforated wall of the drum. Apparatus of this character enable a relatively small breaker/crusher to effectively duplicate the performance of much larger existing units, while successfully controlling the production of fines.