Abstract: An apparatus is provided for extracting cross-sectional samples of bulk material from a moving belt conveyor with a rotating sample cutter. The sample cutter is driven around a circular sampling path by a pair of double-acting pneumatic cylinders that are connected to angularly offset crank throws. Fluid flow in and out of each pneumatic cylinder pressure chamber is independently regulated as a function of the respective cylinder rod position and direction of movement whereby both chambers may be simultaneously open to the pressure supply or to the atmospheric vent for a brief rotational arc.

Abstract: A method and apparatus is provided for cross-stream sampling of bulk material distributed as a mounded continuum in a trough formed along the length of a belt conveyor. A rotating cutter passes transversely through the traveling, bulk material continuum to extract substantially all material on said belt in a swath between transverse, parallel cutting planes. Proximate of the sample cutting swath, before and after such swath relative to the material traveling direction, rigid skirting is provided to overlay both lateral edges of the belt. Garlands of resiliently mounted belt supporting idlers span under the belt laterally of the swath to urge the belt into a substantially continuous line of sealed contact with the skirting. Simultaneously, the trough bight of the belt between the skirting is urged into the swath volume to require displacement from the swath volume by passage of the sample cutter thereby insuring full belt surface contact by the cutter and maximum small particle retrieval.

Abstract: A spin riffle sampling apparatus distributes a sample source quantity of particulate material in a predetermined number of increments, 60 for example, to each of a smaller number, 4 for example, of radially disposed bins on a rotating platform. The bins include top openings which pass through a falling zone of material to receive material into the bins. The width dimension of each opening decreases with increasing radial displacement from the axis of rotation of the platform. The bins also may be forwardly pitched relative to the direction of rotation of the platform so as to induce a down draft to control dusting.