Amca International Corporation

Koehring Canada Limited

Allan J Wildey

A centrifugal grinder has an internal grinding surface shaped as a surface of revolution, and a rotor mounted within the surface for rotation about the axis of the grinding surface. The rotor defines a generally axial inlet passageway for wood chips to be ground, and at least one pocket extending generally outwardly from the axis of the rotor toward the grinding surface. The pocket is provided with a configuration such that its cross section increases at an increasing rate away from the rotor axis. This encourages the wood chips to orient themselves parallel to the grinding surface, such that they take up such parallel orientation by the time they reach the grinding surface.

Flared pockets for centrifugal grinders

A centrifugal grinder for pulp wood and wood chips has a stationary internal grinding surface and a rotor rotating within the surface. The rotor has an axial feed passage for stock to be ground, and at least one passageway extending from the passage to the grinding surface. A guideway in the rotor is disposed at an angle to the grinding surface and is located such that, as the rotor rotates, the guideway sweeps over the portion of the grinding surface in contact with the stock to be ground. A sealing bar is located in the guideway, the bar being of a material softer than the grinding surface so that it can be worn down into conformity with the surface. A rack within the guideway is connected to the sealing bar, and a pinion engages the rack. The rotational position of the pinion can be incrementally adjusted to advance the sealing bar toward the grinding surface, and the play between the rack and the pinion is sufficient to allow the sealing bar to be worn into substantial conformity with the grinding surface after the surface has been sharpened.

Sealing bar for centrifugal grinders

A centrifugal grinder with an internal grinding surface and a rotor turning within that surface includes a passage for inserting material axially into the rotor and a pocket to allow the material to contact the internal grinding surface. A spray is provided on the rotor at a location trailing the pocket, to spray liquid against the internal surface and make a slurry with ground material. An element of air-foil shape is mounted on the rotor at a location trailing the spray, the air-foil having a rounded contacting portion juxtaposed against the internal grinding surface, and have the effect of lifting the slurry away from the surface. A scoop trails the foil and has a leading edge juxtaposed against the internal grinding surface, defining a pocket for collecting the scooped-up slurry. A compartment is located axially beyond the grinding surface and a passage allows the scooped up slurry to pass from the pocket of the scoop to the compartment.

Foil arrangement for centrifugal grinder

A method and apparatus for grinding woodchips into pulp provides an internal grinding surface of circular section defining a cavity in which a rotor rotates. The rotor has a pocket extending to the grinding surface from an inlet spaced inwardly from the grinding surface, and the rotation of the rotor gives rise to centrifugal force urging woodchips against the surface, the woodchips entering at the inlet. The woodchips form a compact plug of material filling the pocket adjacent the surface, and the woodchips are ground to pulp and then removed from the surface to a discharge. A pressure differential is placed across the plug of material in the sense to urge the woodchips in the plug more strongly against the grinding surface, so that the woodchips can press with a satisfactory grinding force against the surface without requiring an excessive rotational speed.

Pressure-assisted centrifugal grinding

There is provided a centrifugal grinder which utilizes an internal grinding surface in the shape of a surface of revolution. A rotor is mounted coaxially within the grinding surface and has a central cavity defining at least one pocket through which material in the central cavity can contact the grinding surface. Material for grinding is delivered to the central cavity, and means are provided for rotating the rotor. Further means are incorporated in the rotor for applying water to the grinding surface.

Apparatus for centrifugal pulpwood and wood chip grinding

Tree cutting equipment that may constitute a part of the head of a tree harvester includes a saw assembly and a shear assembly, the shear and saw being movable towards each other, preferably in substantially the same plane. A stop associated with the shear assembly and engageable with the saw assembly limits the extent to which the saw can approach the shear so as to prevent the saw from attempting to cut completely through the trunk of a tree located between the shear and saw. The stop is located on the side of the pivot point for the saw that is remote from the shear, and a window is provided in the arm that supports the shear to permit the ejection of saw chips.

Tree harvester with saw and shear

In an apparatus for de-limbing trees, there is provided a carriage moving longitudinally on a rail, and having a pair of de-limbing arms adjacent one end which are mounted for pivoting movement with respect to the carriage. Each arm defines a concavity adapted to pivot into contact with a tree held in an upper recess in the carriage, and there are means for urging the arms against the tree. Each arm has a first cutting edge along the forward margin and a second cutting edge along the rearward margin, the first cutting edge being offset inwardly with respect to the second, such that the first cutting edge after passing forwardly beyond the stump of a tree limb which it has severed, can shift inwardly to lie against the tree trunk so that the next cut is made as close as possible to the trunk.

Growing community of inventors

Brantford, Canada

Allan J Wildey