Food pump

A pumping assembly, comprising:

• an elongated, stationary, tubular body presenting a material inlet end configured to be coupled with a source of material to be pumped, a material outlet end for directing pumped material to an outlet device, and a pump opening;
• an elongated, stationary, tubular pumping chamber operatively connected with said pump opening of said tubular body;
• a spool within said tubular body presenting an outer surface and having a material inlet port, a pumped material outlet port, first and second operating ports, a first passageway interconnecting said first operating port and said material inlet port, and a second passageway interconnecting said second operating port and said material outlet port, said spool presenting an arcuate outer surface;
• a piston within said pumping chamber and shiftable between a fill position, a compression position, and a discharge position;
• and
• a drive operably coupled with said spool for selective shifting of the spool between a pumping chamber fill position where said spool first operating port is in communication with said pumping chamber, a material compression position where said imperforate surface covers said pump opening, and a material discharge position where said second operating port is in communication with said pumping chamber,
• said piston operable to shift within said pumping chamber when said spool is in said pumping chamber fill position in order to introduce material into the pumping chamber from said source through said first passageway, to compress said introduced material within the pumping chamber when said spool is in said material compression position, and to discharge said compressed material through said second passageway when said spool is in said discharge position.

A pumping unit, comprising:

• structure defining a hopper for holding a material to be pumped;
• a pumped material outlet device;
• and
• a pumping assembly operably interposed between said hopper and said pumped material outlet device, said pumping assembly including—
• an elongated, stationary, tubular body presenting a material inlet end operatively coupled with said hopper, and a material outlet end operatively coupled with said pumped material outlet device, and a pump opening;
• an elongated, stationary, tubular pumping chamber operatively connected with said pump opening of said tubular body;
• a spool within said tubular body having a material inlet port, a pumped material outlet port, first and second operating ports, a first passageway interconnecting said first operating port and said material inlet port, and a second passageway interconnecting said second operating port and said material outlet port, said spool presenting an arcuate outer surface;
• a piston within said pumping chamber and shiftable between a fill position, a compression position, and a discharge position,
• said piston having an arcuate face complemental with said arcuate outer surface of said spool;
• and
• a drive operably coupled with said spool for selective shifting of the spool between a pumping chamber fill position where said spool first operating port is in communication with said pumping chamber, and a material discharge position where said second operating port is in communication with said pumping chamber,
• said piston operable to shift within said pumping chamber when said spool is in said pumping chamber fill position in order to introduce material into the pumping chamber from said hopper through said first passageway, and to discharge said material within said pumping chamber through said second passageway when said spool is in said discharge position,
• said piston face being in close adjacency to said spool arcuate surface in said discharge position thereof.

A pumping unit, comprising:

• structure defining a hopper for holding a material to be pumped;
• a pumped material outlet device;
• and
• a pumping assembly operably interposed between said hopper and said pumped material outlet device, said pumping assembly including—
• an elongated, stationary, tubular body presenting a material inlet end operatively coupled with said hopper, a material outlet end operatively coupled with said outlet device, and a pump opening;
• an elongated, stationary, tubular pumping chamber operatively connected with said pump opening of said tubular body;
• a spool within said tubular body presenting an outer surface and having a material inlet port, a pumped material outlet port, first and second operating ports, a first passageway interconnecting said first operating port and said material inlet port, and a second passageway interconnecting said second operating port and said material outlet port, said spool presenting an arcuate outer surface;
• a piston within said pumping chamber and shiftable between a fill position, a compression position, and a discharge position;
• and
• a drive operably coupled with said spool for selective shifting of the spool between a pumping chamber fill position where said spool first operating port is in communication with said pumping chamber, a material compression position where said imperforate surface covers said pump opening, and a material discharge position where said second operating port is in communication with said pumping chamber,
• said piston operable to shift within said pumping chamber when said spool is in said pumping chamber fill position in order to introduce material into the pumping chamber from said hopper through said first passageway, to compress said introduced material within the pumping chamber when said spool is in said material compression position, and to discharge said compressed material through said second passageway when said spool is in said discharge position.