US 12,411,503 B2
High turn down ratio direct control for variable displacement pumps with flow sensing
Ryan Prescott Susca, Windsor, CT (US); and Ryan Shook, Loves Park, IL (US)
Assigned to Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed by Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed on Jan. 13, 2023, as Appl. No. 18/096,949.
Prior Publication US 2024/0241526 A1, Jul. 18, 2024
Int. Cl. G05D 7/06 (2006.01); F02C 7/22 (2006.01); F02C 7/236 (2006.01); F02C 9/30 (2006.01); F04B 49/00 (2006.01); F04B 49/035 (2006.01); F04B 49/06 (2006.01); F04B 49/22 (2006.01); F04B 49/24 (2006.01)
CPC G05D 7/0688 (2013.01) [F02C 7/22 (2013.01); F02C 7/236 (2013.01); F02C 9/30 (2013.01); F04B 49/002 (2013.01); F04B 49/035 (2013.01); F04B 49/065 (2013.01); F04B 49/22 (2013.01); F04B 49/24 (2013.01); G05D 7/0623 (2013.01); F04B 2205/05 (2013.01); F04B 2205/09 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method comprising:
Receiving sensor feedback from a flow sensing valve (FSV) indicative of flow demanded by a downstream system supplied from an outlet line of a variable displacement pump (VDP);
operating an electrohydraulic servo valve (EHSV) such that a pressure of a control line for a bypass valve (BPV) is lower in response to the sensor feedback dropping below the predetermined low threshold of flow through the VDP;
opening the BPV to redirect flow from the pump outlet line to a system inlet line in reaction to the pressure of the control line being lower; and
controlling a second EHSV such that a second pressure of a second control line for a variable displacement mechanism of the VDP is varied, and thereby varying a pressure of the pump outlet line.