Dept. of Agricultural & Biological Engineering University of Illinois ABE 223: ABE Principles – Machine Systems Regenerative Circuits Tony Grift Dept. of Agricultural & Biological Engineering University of Illinois

Differential area cylinder: Flow and displacement Force Equilibrium Velocity of piston Dept. of Agricultural Engineering University of Illinois

Conventional advance in circuit Dept. of Agricultural Engineering University of Illinois

Force equilibrium during Regenerative advance Dept. of Agricultural Engineering University of Illinois

Velocity during Regenerative advance KCL in node N Velocity of piston (differential area cylinder) Dept. of Agricultural Engineering University of Illinois

Velocity during Regenerative advance Dept. of Agricultural Engineering University of Illinois

Velocity during Regenerative advance Dept. of Agricultural Engineering University of Illinois

Summary Conventional Regenerative Force: Velocity:   Conventional Regenerative Force: Velocity: Dept. of Agricultural Engineering University of Illinois

Summary cont. In other words, during regenerative advance, the cylinder behaves as if its cap end area is equal to the rod area which is equal to Cap end Area Rod end Area (Annular) Rod Area Dept. of Agricultural Engineering University of Illinois

Regenerative advance in circuit Dept. of Agricultural Engineering University of Illinois

Regenerative advance in circuit with switchover (pressurize cap and rod end) Conventional (rod end to tank) Dept. of Agricultural Engineering University of Illinois

Conventional advance (v = 0.17 ms^-1) Dept. of Agricultural Engineering University of Illinois

Regenerative advance (v=0.43 ms^-1) Dept. of Agricultural Engineering University of Illinois

Why Regenerative Circuits Benefit of fast advance Example Press a workpiece Advance (extend) cylinder rapidly (regeneratively) with reduced force, using rod area (not annular) Detect increased pressure when press makes contact Switch automatically to conventional advance Press the work piece with full force (using cap end area) There is only regenerative advance (extension), no retraction Dept. of Agricultural Engineering University of Illinois

Dept. of Agricultural Engineering University of Illinois

Dept. of Agricultural & Biological Engineering University of Illinois ABE 223 Agricultural & Biological Engineering I OREE section Regenerative Circuits The End Dept. of Agricultural & Biological Engineering University of Illinois