Gas turbine engine lubrication system
A lubrication system includes a lubrication tank, a gearbox driven pump, an electrically driven pump located in parallel with the gearbox driven pump, and a first control valve for selectively connecting the electrically driven pump or the gearbox driven pump with the lubrication tank.
1. A lubrication system comprising:
a lubrication tank;
a gearbox driven pump;
an electrically driven pump located in parallel with the gearbox driven pump; it 4 a first control valve for selectively connecting the electrically driven pump or the gearbox driven pump with the lubrication tank;
a second control value located downstream of an output to the gearbox driven pump and an output to the electrically driven pump; and
a third control valve located downstream of the second control valve configured to selectively move between a first position for providing lubricant to a speed change mechanism and bearing systems and a second position for providing lubricant only to the speed change mechanism.
2. The lubricant system as recited in claim 1 , wherein the first control valve and the second control valve are configured to selectively move between a first position to allow lubricant only through the gearbox driven pump and a second position to allow lubricant only through the electrically driven pump.
3. The lubrication system as recited in claim 1 , including a third control valve located downstream of the second control valve for selectively directing lubrication between at least one of a speed change mechanism on a gas turbine engine and rotor support bearings on the gas turbine engine.
4. The lubrication system as recited in claim 3 , including a lubrication cooler located downstream of the second control valve and upstream of the third control valve.
5. The lubrication system as recited in claim 1 , wherein the electrically driven pump receives power from a vehicle power distribution control.
6. The lubrication system as recited in claim 5 , wherein the power distribution control is in electrical communication with a first gas turbine engine and a second gas turbine engine.
7. The lubrication system as recited in claim 1 , including a gearbox for driving the gearbox driven pump.
8. The lubrication system as recited in claim 7 , including a tower shaft mechanically connecting the gearbox with a high speed spool.