# US 2014/0150439 A1 · Lubrication System for Gas Turbine Engines > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150439 A1 - Document ID: US20140150439A1 - Status: Published application - Kind: A1 - Application number: 13/690,767 - Filed: 2012-11-30 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: United Technologies Corporation - Applicants: United Technologies Corporation - Inventors: Francis Parnin; Paul H. Dolman; David M. Daley; Denman H. James; Richard W. Clark - Web page: https://patentgrep.com/patent/US20140150439A1 ## CPC - F02C 7/06: Arrangements of bearings (bearings F16C); Lubricating ({of turbo machines F01D25/18; of machines or} engines in general F01M) - F01D 25/20: using lubrication pumps - F05D 2270/301: Pressure - F05D 2270/304: Spool rotational speed - F05D 2270/331: Mechanical loads - F05D 2270/332: Maximum loads or fatigue criteria - F05D 2270/335: Output power or torque - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00) - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A lubrication system is disclosed. The lubrication system may be used in conjunction with a gas turbine engine for generating power or lift. The lubrication system utilized a flow scheduling valve which reduces lubricant flow to at least one component based on an engine load. The lubrication system may further include a main pump which may be regulated by an engine speed. Thus, a lubrication system which provides a lubricant to engine components based on the load and speed of the engine is possible. The system may improve efficiency of the engine by reducing the power previously spent in churning excess lubricant by at least one engine component as well as reducing the energy used by a lubricant cooler in cooling the excess lubricant. The lubricant cooler size may also be minimized to reduce weight and air drag due to the reduced lubricant flow. ## Claims ### Claim 1 A lubrication system for a gas turbine engine, the system comprising: a main pump for moving a lubricant through a main conduit from a lubricant tank to an engine component; and a flow scheduling valve positioned in the main conduit between the main pump and the engine component, the flow scheduling valve limiting flow of the lubricant to the engine component based on a calculated load condition of the gas turbine engine, and redirecting excess lubricant through a return conduit to the lubricant tank. ### Claim 2 (depends on 1) The lubrication system of claim 1, further comprising a lubricant cooler connected to a main conduit. ### Claim 3 (depends on 2) The lubrication system of claim 2, wherein the lubricant cooler is positioned between the main pump and the engine component. ### Claim 4 (depends on 1) The lubrication system of claim 1, further comprising a fixed flow metering orifice positioned in the main conduit between the main pump and the engine component, the metering orifice allowing lubricant to bypass the engine component via a bypass conduit and return to the lubricant tank. ### Claim 5 (depends on 1) The lubrication system of claim 1, wherein the calculated engine load is calculated by a processor based on a combustor pressure. ### Claim 6 (depends on 1) The lubrication system of claim 1, wherein the engine load is calculated by a processor based on a fan speed measured by a speed sensor. ### Claim 7 (depends on 1) The lubrication system of claim 1, wherein operation of the main pump is regulated by an engine speed. ### Claim 8 (depends on 1) The lubrication system of claim 1, further comprising a manifold positioned in the main conduit between the main pump and the flow scheduling valve, the manifold being connected to the engine component via a side conduit to allow the engine component to receive a lubricant flow not reduced by the flow scheduling valve. ### Claim 9 A gas turbine engine having an engine component requiring lubrication and comprising: a compressor; a combustor downstream of the compressor; a turbine downstream of the combustor; a lubrication tank; a main conduit in fluid communication with the lubrication tank; and a flow scheduling valve positioned in a main conduit between the lubricant tank and the engine component requiring lubrication, the flow scheduling valve limiting flow of lubricant from the lubricant tank to the engine component based on a load on the engine component and redirecting excess lubricant through a return conduit to the lubricant tank. ### Claim 10 (depends on 9) The gas turbine engine of claim 9, further comprising a main pump connected to the main conduit and adapted to pump the lubricant from the lubricant tank to the engine component. ### Claim 11 (depends on 10) The gas turbine engine of claim 10, wherein operation of the main pump is driven by a drivetrain mechanically connected to an engine rotor. ### Claim 12 (depends on 9) The gas turbine engine of claim 9, wherein the load on the engine component is calculated by a processor based on a parameter measured by one of a pressure sensor and speed sensor. ### Claim 13 (depends on 9) The gas turbine engine of claim 9, further comprising a lubricant cooler. ### Claim 14 (depends on 9) The gas turbine engine of claim 9, further comprising a manifold positioned in the main conduit between the lubricant tank and the flow scheduling valve and connected to the engine component via a side conduit, the manifold allowing the engine component to receive a flow of lubricant not reduced by the flow scheduling valve. ### Claim 15 A method of lubricating a component of a gas turbine engine, comprising: pumping a lubricant from a lubricant tank through a main conduit to an engine component by a main pump; calculating a load condition of the engine; and limiting the flow of the lubricant to the engine component with a flow scheduling valve, the limiting of the flow being based on a calculated load condition of the engine. ### Claim 16 (depends on 14) The method of claim 14, further comprising directing excess lubricant from the flow scheduling valve through a return conduit to the lubricant tank by way of the flow scheduling valve. ### Claim 17 (depends on 14) The method of claim 14, further comprising measuring an engine combustor pressure and calculating the load on the engine by a processor based on the measured combustor pressure. ### Claim 18 (depends on 14) The method of claim 14, further comprising measuring an engine fan speed and calculating the load on the engine by a processor based on the measured fan speed. ### Claim 19 (depends on 14) The method of claim 14, further comprising regulating the lubricant flow from the main pump based on an operating speed of the gas turbine engine. ### Claim 20 (depends on 14) The method of claim 14, further comprising redirecting lubricant from the main conduit through a bypass conduit to the lubricant tank.