US 12,071,898 B2
Fluid pump systems
Adrian L. Stoicescu, Roscoe, IL (US)
Assigned to Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed by Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed on Jul. 30, 2021, as Appl. No. 17/390,638.
Prior Publication US 2023/0034465 A1, Feb. 2, 2023
Int. Cl. F02C 7/236 (2006.01); F02C 7/232 (2006.01); F02C 9/30 (2006.01); F04D 1/06 (2006.01); F04D 1/10 (2006.01); F04D 9/04 (2006.01); F04D 13/12 (2006.01); F04D 15/00 (2006.01); F04D 15/02 (2006.01)
CPC F02C 7/236 (2013.01) [F02C 7/232 (2013.01); F02C 9/30 (2013.01); F04D 1/06 (2013.01); F04D 1/10 (2013.01); F04D 13/12 (2013.01); F04D 15/0072 (2013.01); F04D 9/04 (2013.01); F04D 15/0218 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A multi-stage fluid pump system, comprising:
a first stage configured to provide a first pressure;
a second stage configured to provide a second pressure,
wherein the first stage is upstream of the second stage,
wherein the pump system is configured to:
prevent output of the second stage in a first stage mode such that only the first pressure is output from the first stage and second stage;
allow output of the second stage in a multi-stage mode such that there is a combined pressure output from the first stage and the second stage; and
a first check valve disposed downstream of the first stage at a first stage outlet between the first stage and a main discharge line; wherein the first stage and the second stage are driven by a common shaft, wherein the system further comprises an ejector pump in fluid communication between the first stage and a main inlet line.