The specification discloses a two-press grinding machine for the reduction of wood to small particle sizes. A grinding wheel is fixed to a horizontal shaft and is rotated thereby. Two presses are provided on opposite sides of the wheel to press logs of wood against the periphery of the grinding wheel and the axes of the presses are horizontal and are located above the axis of rotation of the grinding wheel. The location of the press axes above the horizontal plane of the shaft axis has the advantage that the shaft of the grinding wheel in any condition of operation of the machine will always make contact with the lower region of its bearing surfaces while, furthermore, the horizontal arrangement of the presses results in a simple construction of the machine.
A blocking slab for a pulp grinder, which blocking slab comprises a striplike frame to be mounted between a wall of a grinding chamber in the grinder and a grindstone, said frame being parallel to the axle of the grindstone. In order to prevent splinters and chips from getting out of the grinding chamber, the frame is provided with a longitudinal retaining edge facing to the peripherical surface of the grindstone. The retaining edge has at least one longitudinal recess, which is limited by two longitudinal retaining ribs, to prevent splinters and chips from getting out of the gap between the grindstone and the blocking slab.
A blocking slab is used in a grinding chamber of a pulpwood grinder having a rotatable grindstone. The pulpwood grinder is suitable for reducing wood into pulp and objectionable shims and shives. The blocking slab includes a retaining side extending the length of the grindstone for permitting the passage of pulp. The blocking slab also includes a plurality of ribs forming a collecting channel proximate the retaining side and extending the length of the grindstone for collecting shims and shives therein. The plurality of ribs are angled for directing the shims and shives collected in the collecting channel toward the ends of the grindstone thus providing further reduction of the shims and shives.
This invention is directed to a chips making machine equipped with at least one wood-working tool including a wood-machining edge on the working tool, which is mounted on the periphery of the rotatable tool-holder. The machine is also equipped with a device for feeding the wood against the machining edge. The edge of the wood-working tool is designed for the production of long chips of wood mainly by shearing stresses in layers which are mainly positioned between the wood fibers and are approximately parallel with the direction of the fibers.
A material shredding device is disclosed which comprises a power source, a first shaft and a second shaft disposed in generally parallel relation and being in communication with the power source for opposite reciprocating rotational movement about respective axes thereof, a plurality of blades attached to the first shaft and the second shaft which are interleaved so as to overlap over a central shredding area and undergo opposite reciprocating rotational movement with the shafts between first and second positions and a material feeding mechanism.
