Comminuting apparatus and pneumatic recirculation systems for comminuting apparatus

A comminuting apparatus, comprising:

• a frame having an enclosure with an entrance opening for receiving waste material;
• at least one drive motor carried by the frame;
• a set of overlapping scissor rolls including a first scissor roll and a second scissor roll carried within the enclosure for co-rotation and driven by the at least one drive motor, configured to draw material from beneath for delivery between the overlapping scissor rolls to subdivide the material;
• a recycle manifold provided above and downstream of the scissor rolls and configured to receive the subdivided material from between the overlapping scissor rolls;
• a pneumatic conveyor comprising a source of air and a pneumatic duct communicating with the recycle manifold, the source of air comprising a centrifugal fan and an outer volute duct extending from the centrifugal fan to an overflow air recirculation pipe that communicates with the pneumatic duct via an overflow outlet, the pneumatic duct comprising a plurality of overflow plenum slots communicating between the pneumatic duct and the recycle manifold and extending across the recycle manifold above and substantially parallel with the scissor rolls and configured to deliver an air stream from the source of air into the recycle manifold to entrain subdivided pieces and move the subdivided pieces from the recycle manifold for further conveying and subdividing within the comminuting apparatus;
• and
• a deflector downstream of the overflow plenum slots configured to direct the source of air to impinge against subdivided pieces of material that accumulate in the recycle manifold to further convey the subdivided pieces to cascade over an overflow fence of the frame extending between the recycle manifold and a recirculation cavity.

In a comminuting apparatus having intermeshing cutting blades carried by a frame within an enclosure and a recycle manifold provided above the blades for collecting material subdivided by the blades and an overflow fence along the recycle manifold over which subdivided material cascades for delivery back into the blades, the invention comprising:

• a pneumatic conveyor for generating a source of air;
• a recirculation air pipe communicating with the pneumatic conveyor at a first end;
• and
• an air delivery duct comprising a plurality of overflow plenum slots communicating with the pneumatic conveyor via the recirculation air pipe at a second end and configured to deliver a stream of air into the recycle manifold to impinge upon subdivided material that collects within the recycle manifold behind and above the overflow fence so as to encourage movement of the recycled material over the overflow fence and into the recirculation cavity for further comminuting.

In a comminuting apparatus having intermeshing cutting blades carried by a frame within an enclosure and a recycle manifold provided above the blades for collecting material subdivided by the blades and an overflow fence along the recycle manifold over which subdivided material cascades for delivery back into the blades, the invention comprising:

• a pneumatic conveyor for generating a source of air;
• a recirculation air pipe communicating with the pneumatic conveyor at a first end;
• an air delivery duct communicating with the pneumatic conveyor via the recirculation air pipe at a second end for delivering a source of air into the recycle manifold to impinge upon subdivided material that collects within the recycle manifold behind and above the overflow fence so as to move the recycled material over the overflow fence for further comminuting;
• and
• an entrance air duct provided adjacent an entrance slot of the comminuting apparatus configured to deliver a stream of air between a sheet of material being received within the entrance slot and an inner wall of an enclosure of the comminuting apparatus.

An air recirculation system, comprising:

• a comminuting apparatus having a recycle housing and a recycle manifold with an overflow fence where subdivided pieces of material cascade from the recycle manifold over the overflow fence for further comminuting via intermeshing cutting blades;
• a source of air providing a pneumatic conveyor including a pneumatic fan;
• an overflow air recirculation pipe communicating with the source of air;
• and
• a recycling air delivery duct cooperating with the recycle housing to provide an overflow plenum including a plurality of overflow plenum slots and communicating with the source of air via the overflow air recirculation pipe and configured to eject the source of air at an increased velocity to impinge the source of air upon subdivided material collecting in and above the recycle manifold to encourage moving the subdivided material over the overflow fence for further comminuting between the intermeshing cutting blades;
• and
• a flow deflector provided downstream of the plurality of overflow plenum slots and configured to direct the source of air leaving the overflow plenum slots so as to impinge upon the subdivided material collecting above the recycle manifold to cause cascading of the recycled material over the overflow fence for further comminuting between the intermeshing cutting blades.

A comminuting apparatus, comprising:

• a frame;
• an enclosure carried by the frame having a material receiving duct for receiving a sheet of material;
• at least two intermeshing scissor rolls carried within the enclosure and configured to subdivide the sheet of material;
• and
• a pneumatic conveyor for a sheet of material entering the enclosure via the material receiving duct, the pneumatic conveyor including a source of air and an entrance air duct provided adjacent the entrance and within the enclosure, and configured to deliver a stream of air between the sheet of material and an inner wall of the enclosure within the material receiving duct.