Patent ID: 8834134
Filing Date: 2014-09-16
Classification: F02C,F04B,F05D

Abstract:
1. A switching system for use with a dual pump fuel supply system for an aircraft engine, the dual pump fuel supply system including a first pump having a first high pressure output coupled to a high pressure supply to a fuel metering unit, wherein the fuel metering unit is configured to supply a portion of the fuel supply to an engine and to return a bypass flow of the fuel supply to a low pressure return that is coupled to a first low pressure supply to the first pump, and a second pump having a second high pressure output and a second low pressure supply that is coupled to the low pressure return, the second pump also having a second pump bypass that is coupled to the second low pressure supply, comprising: means for sensing the bypass flow coming directly from the fuel metering unit; means, operatively coupled to the means for sensing the bypass flow coming directly from the fuel metering unit, for controlling a pressurization of the second pump; and means for adding or subtracting the second high pressure output from the second pump to the first high pressure output from the first pump, wherein said means for adding are downstream from the first and second high pressure outputs and upstream from the fuel metering unit.