High-low system for balers, compactors and transfer station compactors

A high-low hydraulic system comprising:

• a. at least one double rotary pump;
• wherein each double rotary pump comprises a big displacement pump and a small displacement pump;
• wherein the big displacement pump and small displacement pump each have an inlet and at least one outlet;
• b. a motor;
• c. a plurality of hydraulic fluid conduits;
• d. a tank;
• e. a cylinder;
• wherein the cylinder comprises a tubular housing, a rod, and a piston;
• wherein the tubular housing provides a hermetically sealed interior chamber;
• wherein the piston comprises a blind end side and a rod end side;
• f. one or more regenerative blocks;
• g. a plurality of one-way valves;
• h. a plurality of directional control valves;
• wherein the plurality of directional control valves comprises at least one two-stage valve;
• wherein each two-stage valve provides a pressure port, a tank port, two actuator ports, a pilot pressure port, and a pilot drain port;
• wherein the two actuator ports comprise a first actuator port (A) and a second actuator port (B);
• i. a plurality of pressure switches;
• j. one or more flow control valves;
• k. a pilot-operated back pressure reducing valve;
• wherein the pilot-operated back pressure reducing valve has an inlet and an outlet;
• wherein the pilot-operated back pressure reducing valve has a pilot line;
• wherein the pilot line is directly connected to an output of the second actuator port (B) of each two-stage valve;
• wherein the outlet of the pilot-operated back pressure reducing valve is fluidly coupled to the blind end side;
• wherein the inlet of the pilot-operated back pressure reducing valve is fluidly coupled to the tank;
• l. an accumulator;
• m. a pressure transducer;
• wherein the pressure transducer is electronically coupled to a solenoid-controlled, four way 3-position directional control valve that fluidly couples the small displacement pump to the blind end side.