Patent attributes
An emergency lubrication system for a turbine engine includes a reservoir 50 containing a reserve quantity of lubricant 52 and having a lubricant inlet 54 and a lubricant outlet 56. A lubricant supply line 62 and a lubricant outlet line 66 each have a respective valves 64, 68 for regulating lubricant flow into and out of the reservoir. A fluid supply line 70 includes a valve 72 for selectively establishing communication between the reserve quantity of lubricant and a source of pressurized fluid. During normal operation the lubricant outlet valve continuously releases lubricant at a normal rate to the component requiring lubrication while the lubricant inlet valve concurrently admits fresh lubricant into the reservoir. During abnormal operation, the lubricant inlet valve closes in response to abnormally low lubricant pressure outside the reservoir thereby preventing backflow of reserve lubricant out of the reservoir. The fluid inlet valve opens to admit pressurized fluid into the reservoir thus pressurizing the reserve lubricant. The lubricant outlet valve opens or cycles open and closed in response to a command from a controller 26 so that the pressurized fluid forces lubricant through the outlet 56 as a subnormal rate, which persists until the lubricant reserve is substantially depleted. The subnormal rate is ideally achieved by intermittently releasing lubricant from the reservoir, but may also be achieved by releasing a continuous stream of lubricant at a rate less than the normal rate of release.