Patent ID: 8307626

Claim:
A pump system for lubricating a bearing in a gear system of a gas turbine, the pump system comprising: a main pump fluidically connected to the bearing through a main supply passage; an auxiliary pump mechanically connected to the gear system, wherein the auxiliary pump is fluidically connected to the bearing through an auxiliary supply passage and to a reservoir through an auxiliary scavenge passage; an auxiliary valve fluidically connected to the auxiliary supply passage, for transferring liquid from the auxiliary pump to the bearing when a pressure in the auxiliary supply passage downstream of the auxiliary valve is less than a particular threshold, and for transferring liquid from the auxiliary pump to the reservoir when the pressure in the auxiliary supply passage downstream of the auxiliary valve is greater than the particular threshold; and a compartment wall defining a compartment cavity, wherein the reservoir is positioned at a bottom of the compartment cavity, wherein a portion of the compartment wall defines the reservoir, and wherein the compartment cavity contains the auxiliary pump, the auxiliary valve, and the bearing.