×

Control system for hydraulic system and method for recovering energy and leveling hydraulic system loads

  • US 9,765,501 B2
  • Filed: 12/19/2013
  • Issued: 09/19/2017
  • Est. Priority Date: 12/19/2012
  • Status: Active Grant
First Claim
Patent Images

1. A method of delivering power in a hybrid work machine, the method comprising:

  • determining engine power of an engine;

    determining accumulator pressure of an accumulator;

    determining a first target power flow to/from a first work machine component;

    determining a second target power flow to/from a second work machine component;

    setting an operating mode to a first mode if the second target power flow is substantially zero;

    setting the operating mode to a second mode if the first target power flow is substantially zero;

    setting the operating mode to a third mode if the first and second target power flows are both substantially non-zero;

    flow sharing a first power flow from a main pump mechanically connected to the engine and from a transformer fluidly connected to the accumulator when the accumulator pressure is below a first threshold value and the operating mode is set to the first mode and the accumulator is available for discharge;

    supplying the first power flow from the transformer when the accumulator pressure is above the first threshold value and the operating mode is set to the first mode;

    supplying the first power flow from the main pump when the operating mode is set to the first mode and the accumulator is unavailable for discharge;

    flow sharing a second power flow from the main pump and from the transformer when the accumulator pressure is below a second threshold value and the operating mode is set to the second mode and the accumulator is available for discharge;

    supplying the second power flow from the transformer when the accumulator pressure is above the second threshold value and the operating mode is set to the second mode; and

    supplying the second power flow from the main pump when the operating mode is set to the second mode and the accumulator is unavailable for discharge.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×