Apparatus for reducing fiber material to chip form

An apparatus for reducing fiber material to chip form, including anvil means across which said material is to be fed, at least one knife means, and carrier means for moving said knife means along a path of travel past said anvil means for cooperation therewith to effect severing of said material into chip form and means for controlling the length of chips being formed, the improvement wherein said anvil means defines an anvil bearing surface arranged to face towards and conform to the contour of said path of travel, said anvil bearing surface including leg portions joined by a connecting portion, said leg portions being spaced apart to accommodate feeding of said material therebetween and across said anvil bearing surface, said knife means including an elongated knife blade having a lengthwise dimension sufficient to bridge between said leg portions, said knife blade including a pair of surfaces converging to define a knife edge extending lengthwise of said knife blade, said carrier means supporting said knife blade for movement along said path of travel and to position at least one of the converging surfaces of the knife blade for surface-to-surface bearing engagement with said anvil bearing surface in a direction extending from adjacent free ends of said leg portions towards said connecting portion, whereby to reduce to chip form said material fed across said anvil bearing surface, said knife blade additionally including a pair of essentially parallel and oppositely facing clamping surfaces, said converging surfaces extending one from each of first marginal edges of said clamping surfaces and forming essentially equal angles relative thereto, and a rear surface joining second marginal edges of said clamping surfaces arranged essentially parallel to said first marginal edges;

• and said carrier means including an elongated adjustment plate having a pair of essentially parallel and oppositely facing clamping surfaces joined by a plate bearing surface having a transverse width corresponding to that of said rear surface and a plurality of essentially parallel slots opening through said clamping surfaces thereof and plate bearing surface, a pair of elongated clamping means having facing clamping surfaces and oppositely facing clearance surfaces forming essentially equal angles relative to their associated clamping surfaces and diverging from adjacent first marginal edges thereof, one of said clamping means having a plurality of bore openings extending through said clamping surface thereof and spaced apart one for alignment with each of said slots, another of said clamping means having a plurality of threaded openings extending through said clamping surface thereof and spaced apart one for alignment with each of said bore openings and slots, and means including a plurality of bolts adapted to be freely inserted one through each of said bore openings and said slots and threaded into said threaded openings for releasably retaining said clamping surfaces of said clamping means in overlapping clamping engagement with said clamping surfaces of said knife blade and adjustment plate and for retaining said plate bearing surface in surface-to-surface abutting engagement with said rear surface and for retaining said clearance surfaces in essential alignment one with each of said converging surfaces.

An apparatus for reducing fibre material to chip form, which comprises in combination:

• a framework;
• a rotor supported on said framework for driven rotation about an axis;
• a plurality of elongated knife blades, each of said knife blades having a pair of surfaces converging to define a knife edge extending lengthwise of its associated knife blade;
• means for supporting said knife blades in spaced relationship about the periphery of said rotor with said knife blades having their knife edges arranged essentially parallel to and equidistant from said axis, and facing in the direction of rotation of said rotor, whereby said knife edges are caused to move along a circular path of travel upon rotation of said rotor, and said knife blades each having one of the converging surfaces thereof disposed essentially tangent to said path of travel;
• a plurality of stop means defining stop surfaces;
• means for supporting said stop means peripherally of said rotor and intermediate said knife blades with said stop surfaces arranged to face radially outwardly of said axis, said stop surfaces being disposed radially inwardly of said path of travel;
• and
• an anvil assembly fixed to said framework and defining an anvil bearing surface, said anvil bearing surface including a pair of leg portions extending generally transversely of said axis and a connecting portion joining said leg portions, said leg portions being spaced apart to accommodate for passage of said material therebetween and across said anvil bearing surface in a direction towards said rotor, each of said knife edges having a lengthwise dimension sufficient to bridge across said leg portions, said anvil bearing surface conforming to the contour of said path of travel, said anvil bearing surface being radially spaced from said axis and arranged relative to said direction of rotation of said rotor for permitting surface-to-surface engagement of said one of said converging surfaces of said knife blades with said anvil bearing surface in a direction extending from adjacent free ends of said leg portions towards said connecting portion, whereby to reduce to chip form said material passing across said anvil bearing surface towards said rotor, and said stop surfaces serving to limit the length of said material passing across said anvil bearing surface.

An apparatus for reducing fibrous material to chip form, which comprises in combination:

• an elongated knife blade, including a pair of surfaces converging to define a knife edge extending lengthwise of said knife blade;
• means for supporting said knife blade to extend essentially horizontally and for vertical reciprocating movements between an upper inoperative position and a lower material severing position, said knife edge being arranged to face downwardly with one of the converging surfaces thereof being arranged to lie within an essentially vertically disposed plane;
• an anvil assembly disposed adjacent one side of said plane and including an anvil bearing surface having generally vertically extending leg portions and a lower leg connecting portion, said anvil bearing surface being arranged essentially coincident with said plane;
• means for guiding said material downwardly across said plane intermediate said leg portions and said connecting portion;
• and
• stop means disposed adjacent an opposite side of said plane and biased to assume a reference position wherein said stop means is to be engaged by said material passing downwardly across said plane, the spacing between said stop means when in said reference position and said anvil bearing surface serving to determine the length of chips to be severed by said knife blade during movement thereof between said upper and lower positions, said stop means being supported for movement from said reference position against said bias in a direction away from said plane incident to passage of said knife blade through said material, and said bias operating via said material during passage of said knife blade therethrough intending to maintain said one of said converging surfaces in surface-to-surface engagement with said anvil bearing surface.

An apparatus for reducing fibrous material to chip form, which comprises in combination:

• a framework;
• an elongated knife blade, said knife blade defining a pair of surfaces converging to define a knife edge extending lengthwise of said knife blade;
• means for supporting said knife blade to extend horizontally of said framework to position said knife edge to face downwardly with one of the converging surfaces thereof arranged to lie essentially within a vertically disposed plane and for effecting vertically directed reciprocating movements of said knife blade between an upper inoperative position and a lower material severing position;
• an anvil assembly fixed to said framework and arranged adjacent one side of said plane, said anvil assembly including a generally U-shaped guide chute for guiding said material for movement in a direction downwardly towards said plane and anvil means outwardly bounding a lower end of said guide chute and serving to define a generally U-shaped anvil bearing surface arranged essentially coincident with said plane;
• and
• a stop plate disposed adjacent an opposite side of said plane and biased to assume a reference position wherein said stop plate is positioned for engagement by said material passing through said guide chute and downwardly across said plane, the horizontal spacing between said stop plate when in said reference position and said anvil bearing surface determining the length of chips to be severed by said knife edge during movement thereof between said upper and lower positions, said stop plate being supported for movement from said reference position against said bias in a direction away from said plane incident to passage of said knife edge through said material, and said bias operating via said material during passage of said knife blade therethrough in tending to maintain said one of said converging surfaces in surface-to-surface engagement with said anvil bearing surface.

An anvil assembly intended to be mounted in a machine in cooperation with at least one knife blade movable along an annular path of travel for reducing fiber material to chip form, said anvil assembly including in combination:

• a guide chute for said material for fiber material to be reduced, said guide chute having an essentially U-shaped cross-sectional configuration and spaced inlet and outlet ends;
• a generally U-shaped anvil bar including a pair of leg portions and a leg connecting portion cooperating to define an anvil bearing surface, said bearing surface being concave in a direction extending from adjacent free ends of said leg portions towards said connecting portion and conforming essentially to the contour of said path of travel;
• and
• support means to removably support said anvil bar outwardly of said guide chute and adjacent said outlet end with said bearing surface projecting beyond said outlet end in a direction away from said inlet end.

An anvil assembly intended to be mounted in a machine in cooperation with at least one knife blade movable along a path of travel for reducing fiber material to chip form, said anvil assembly comprising in combination:

• a frame for mounting said anvil assembly on said machine, said frame having a generally U-shaped lower portion and an upper portion bridging between upper ends of said lower portion;
• an upwardly open guide chute for feeding said material to said machine, said guide chute having an essentially U-shaped cross-sectional configuration and spaced inlet and outlet ends, said outlet end being rigidly fixed to an inner surface of said U-shaped lower portion;
• a generally U-shaped anvil bar having a pair of leg portions and a leg connecting portion cooperating to define an anvil bearing surface conforming essentially to the contour of said path of travel;
• a generally U-shaped strap member having a pair of leg portions and a connecting portion, said leg portions of said strap member having free ends thereof removably fixed to said upper mounting portion for removably clamping said leg portions and said connecting portion of said anvil bar against an outer surface of said U-shaped lower portion thereby to arrange said anvil bearing surface to project beyond said outlet end and said U-shaped lower portion in a direction away from said inlet end.

A method for reducing fiber material to chip form including the steps of:

• providing a knife blade supported for movement along a path of travel, said knife blade being formed of tool steel and having an elongated knife edge defined by a pair of converging surfaces;
• providing an anvil formed of tool steel and shaped to define an anvil bearing surface conforming essentially to the contour of said path of travel;
• moving said knife blade along said path of travel;
• positioning said anvil bearing surface to lie essentially coincident with said path of travel and for sliding surface engagement with one of said surfaces of said knife blade at least adjacent said knife edge, whereby to form the engaged surfaces of said knife blade and said anvil to closely conform to one another and permit uniform surface engagement therebetween and to produce surface hardening of said engaged surfaces;
• passing said material across said anvil bearing surface for engagement by said knife edge as said knife blade moves along said path of travel whereby said knife edge cooperates with said anvil bearing surface to effect severing of a chip from said material;
• and
• periodically resharpening said knife blade by arranging another of said surfaces thereof for sliding surface engagement with said anvil bearing surface.