Face-cutting apparatus for forming pellets

Claim 2

Face cutting apparatus for making pellets of thermoplastic material comprising: a. an extrusion device including at least one concavely shaped die plate means having a plurality of spaced-apart extrusion orifices through which heat-plastified material is adapted to be extruded; b. cutter means having a cylindrical body mounted for rotation about its longitudinal axis which is aligned with the axis of said die plate means, said die plate means cylindrically enclosing the cutter means and having a center concentric with the center of said cutter means; c. said cutter means also having a plurality of spaced-apart blades projecting radially from and extending longitudinally along said body, said die plate means being closedly spaced from said cutter blades all around the periphery of said cutter to define confined channels between said blades d. each of said blades having on its free end, a cutting edge which is closedly spaced adjacent to the downstream face of said die plate means upon rotation of said cutter means and which is adapted to shear heat-plastified material extruded through said orifices into pellets; e. adjacent pairs of said blades and the intervening body portion of said cutter means together with said die plate means establishing longitudinally extending substantially enclosed channels between said blades in which said pellets are adapted to flow.

Claim 3

Face cutting apparatus according to claim 1 wherein said blades are helically arranged on said body.

Claim 4

Face cutting apparatus according to claim 2 including means supplying pellet-treatment fluid to said cutter means to cause said fluid to flow longitudinally over said body and in said channels to flush said pellets toward the other axial end of said cutter means in the same axial direction in which the helically arranged blades advance said pellets during rotation of said cutter means.

Claim 5

Face cutting apparatus according to claim 2 including means associated with said opening for causing ambient air to blow longitudinally of said cutter means for flushing said pellets from said channels.

Claim 6

Face cutting apparatus according to claim 1 wherein said extrusion device includes: a. at least a second cylindrically shaped die plate means having a plurality of radially extending extrusion orifices through which heat-plastified material is adapted to be extruded; b. said cutter means being aligned with the axis of said second die plate means.

Claim 7

Face cutting apparatus according to claim 1 wherein said die plate means comprises a pair of nested die plates one of which is mounted for selective rotatable positioning relative to the other, with each plate of said pair of plates having orifices, and moving means for selectively changing the relative positions of said die plates.

Claim 8

Face cutting apparatus according to claim 6, wherein said moving means comprises a lever attached to the one die plate of said pair of die plates for manually changing the angular position thereof.

Claim 9

Face cutting apparatus for use in making pellets of thermoplastic material comprising longitudinally disposed chamber means, means operatively associated with said chamber means for conveying material in said chamber means for extruding the material therethrough, die plate means arranged downstream of said chamber means having orifice means therein for passing the extrudate therethrough, rotatable cylindrical cutter means disposed with its axis at an angle to the aXis of the chamber means, and with its axis aligned with the axis of the die plate means, said die plate means having at least the portion thereof that faces the chamber means presenting a convex face portion to said chamber means, with the downstream side of said die plate means having a concave inner surface, said cutter means being disposed within said concave inner surface, said cutter means having a plurality of spaced-apart blades projecting radially from and extending longitudinally along said body; each of said blades having on its free end a cutting edge which is spaced at close running clearance from the downstream face of said die plate means upon rotation of said cutter means and which is adapted to shear heat-plastified material extruded through said orifices into pellets; adjacent pairs of said blades and the intervening body portion of said cutter means establishing longitudinally extending channels in which said pellets are adapted to flow.

Claim 10

Face cutting apparatus for use in making pellets of thermoplastic material comprising longitudinally disposed chamber means, means operatively associated with said chamber means for conveying material in said chamber means for extruding the material therethrough, die plate means arranged downstream of said chamber means having orifice means therein for passing the extrudate therethrough, rotatable cylindrical cutter means disposed with its axis at an angle to the aXis of the chamber means, and with its axis aligned with the axis of the die plate means, said die plate means having at least the portion thereof that faces the chamber means presenting a convex face portion to said chamber means, with the downstream side of said die plate means having a concave inner surface, said cutter means being disposed within said concave inner surface, said cutter means having a plurality of spaced-apart blades projecting radially from and extending longitudinally along said body; each of said blades having on its free end a cutting edge which is spaced at close running clearance from the downstream face of said die plate means upon rotation of said cutter means and which is adapted to shear heat-plastified material extruded through said orifices into pellets; adjacent pairs of said blades and the intervening body portion of said cutter means establishing longitudinally extending channels in which said pellets are adapted to flow.

Claim 11

The apparatus of claim 8, wherein said die plate means comprises at least one member of cylindrical configuration.

Claim 12

The apparatus of claim 8, wherein said die plate means comprises a pair of concentric cylinders, a rotatable one of which is disposed inside a fixed said cylinder, with extrudate-passing openings in each said cylinder.

Claim 13

The apparatus of claim 10, wherein the axis of said cutter means intersects said axis of said chamber means at approximately a right angle.

Claim 14

The apparatus of claim 8, wherein said die plate means comprises a pair of nested plate members, the upstream-most one of which is fixedly positioned, and the downstream-most one of which is rotatably movable, with at least said rotatably movable member being of generally cylindrical configuration, with both said plate members having extrudate-passing holes therethrough, and means for rotating said movable plate member relative to said fixedly positioned plate member for bringing holes in said plates into and out of registry with each other.

Claim 15

The apparatus of claim 12, wherein said movable plate member is provided with a plurality of sets of angularly spaced holes, and wherein said rotating means comprises means for selectively positioning any selected one of said sets of holes in registry with the holes in the fixedly positioned plate.

Claim 16

The apparatus of claim 13, including detent means for facilitating the accurate positioning of a selected said set of holes, after movement of said movable plate member.

Claim 17

The apparatus of claim 14, wherein there are three said sets of holes in said movable plate member disposed approximately 120* apart.

Claim 18

The apparatus of claim 14, wherein the sets of holes in said movable plate member are of different size holes from set to set.

Claim 19

The apparatus of claim 14, wherein the sets of holes in said movable plate member are of the same size from set to set.

Claim 20

The apparatus of claim 12, wherein said means for rotating comprise manually engageable lever means.

Claim 21

The apparatus of claim 18, wherein said lever means is of the wrench type having key means engageable within keyway means, and including means for fastening said lever means in a given desired position.

Claim 22

The apparatus of claim 12, wherein said nested die plate members are each of cylindrical configuration, and wherein the axis of said cutter means intersects said axis of said chamber means at approximately a right angle.

Claim 23

The face cutting apparatus defined in claim 1, wherein each of said blades is helically arranged along said cylindrical body at a helix angle relative to the axis of said body of less than 45*.

Claim 24

The face cutting apparatus defined in claim 1, wherein the widths of said channels are less than three times the distance between centers of said orifices.

Claim 25

The face cutting apparatus defined in claim 1, wherein a plurality of rows of orifices are provided in said orifice plate, said rows being concavely shaped.