# US 10,371,096 B2 · Gas turbine engine fan > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,096 B2 - Document ID: US10371096B2 - Status: Granted - Kind: B2 - Application number: 14/943,055 - Filed: 2015-11-17 - Published: 2017-05-18 - Granted: 2019-08-06 - Earliest claimed: 2015-11-17 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Brandon Wayne Miller; Daniel Alan Niergarth; Darek Tomasz Zatorski - Web page: https://patentgrep.com/patent/US10371096B2 ## CPC - F02K 3/06: with front fan - F01D 7/00: Rotors with blades adjustable in operation; Control thereof (for reversing F01D1/30) - F01D 25/16: Arrangement of bearings; Supporting or mounting bearings in casings (bearings per se F16C) - F02C 3/04: having a turbine driving a compressor (power transmission arrangements F02C7/36; control of working fluid flow F02C9/16) - F02C 7/04: Air intakes for gas-turbine plants or jet-propulsion plants - F02C 7/06: Arrangements of bearings (bearings F16C); Lubricating ({of turbo machines F01D25/18; of machines or} engines in general F01M) - F02C 7/36: Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user ({F02C3/107 - F02C3/13 and} F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H) - F04D 29/059: Roller bearings - F04D 29/323: {adjustable} - F04D 29/362: {during rotation} - F05B 2220/302: in gas turbines - F05B 2240/52: Axial thrust bearings - F05D 2240/52: Axial thrust bearings - F05D 2260/40311: of the epicyclical, planetary or differential type - F05D 2260/70: Adjusting of angle of incidence or attack of rotating blades - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - 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) - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F05B: INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G - 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 gas turbine engine includes a core turbine engine and a fan mechanically coupled to the core turbine engine. The fan includes a plurality of fan blades, each fan blade defining a base and an inner end along a radial direction of the gas turbine engine. The fan also includes a hub covering the base of each of the plurality of fan blades. Further, the fan includes one or more bearings for supporting rotation of the plurality of fan blades. The one or more bearings define a fan bearing radius along a radial direction of the gas turbine engine. Similarly, the hub defines a hub radius along the radial direction of the gas turbine engine. The ratio of the hub radius to the fan bearing radius is less than about three, providing for desired packaging of the various components within the fan of the gas turbine engine. ## Claims ### Claim 1 A gas turbine engine defining a radial direction and a longitudinal axis, the gas turbine engine comprising: a core turbine engine; and a fan mechanically coupled to the core turbine engine, the fan comprising a plurality of fan blades, each fan blade defining a base at an inner end along the radial direction; a hub configured to direct an airflow through the plurality of fan blades and covering the base of each of the plurality of fan blades, the hub defining a hub radius along the radial direction between the longitudinal axis and an outermost point of the hub along the radial direction; and one or more bearings for supporting rotation of the plurality of fan blades about the longitudinal axis, the one or more bearings including a ball bearing defining a fan bearing radius along the radial direction, a ratio of the hub radius to the fan bearing radius being less than 1.75; and a power gearbox, wherein the fan is driven by the core turbine engine through the power gearbox. ### Claim 2 (depends on 1) The gas turbine engine of claim 1, wherein the ratio of the hub radius to the fan bearing radius is greater than or equal to one and less than or equal to about 1.5. ### Claim 3 (depends on 1) The gas turbine engine of claim 1, wherein the gas turbine engine is configured to generate a maximum takeoff thrust, and wherein the maximum takeoff thrust is greater than 10,000 pounds and less than 60,000 pounds. ### Claim 4 (depends on 1) The gas turbine engine of claim 1, wherein the one or more bearings include two roller bearings and the ball bearing. ### Claim 5 (depends on 1) The gas turbine engine of claim 1, wherein the fan further comprises a pitch change mechanism for changing a pitch of each of the plurality of fan blades, and wherein the one or more bearings are located outward from the pitch change mechanism along the radial direction. ### Claim 6 (depends on 1) The gas turbine engine of claim 1, wherein the fan further comprises one or more fan counterweights, and wherein the one or more bearings are located outward from the one or more fan counterweights along the radial direction. ### Claim 7 (depends on 1) The gas turbine engine of claim 1, wherein the one or more bearings include a plurality of bearings, and wherein the fan bearing radius is a radius of the innermost bearing along the radial direction. ### Claim 8 (depends on 1) The gas turbine engine of claim 1, wherein the fan bearing radius along the radial direction is a distance from the longitudinal centerline of the gas turbine engine to a central axis or center point of the ball bearing of the one or more bearings. ### Claim 9 (depends on 1) The gas turbine engine of claim 1, wherein the plurality of fan blades are rotatable about an axial direction at a maximum rotational speed during operation of the fan, and wherein the one or more bearings define a DN value during rotation of the plurality of fan blades at the maximum rotational speed of at least 0.54 million and up to 1.65 million. ### Claim 10 (depends on 1) The gas turbine engine of claim 1, wherein the plurality of fan blades are rotatable about an axial direction at a maximum rotational speed during operation of the fan, and wherein the one or more bearings define a DN value during rotation of the plurality of fan blades at the maximum rotational speed of at least 0.72 million and up to 1.65 million. ### Claim 11 A gas turbine engine defining a radial direction and an axial direction, the gas turbine engine comprising: a core turbine engine; and a fan mechanically coupled to the core turbine engine, the fan comprising a plurality of fan blades, each fan blade defining a base at an inner end along the radial direction, the plurality of fan blades rotatable about the axial direction at a maximum rotational speed of less than 9,350 revolutions per minute (RPM) during operation of the fan; a hub configured to direct an airflow through the plurality of fan blades and covering the base of each of the plurality of fan blades, wherein the hub defines a hub radius along the radial direction between a longitudinal axis and an outermost point of the hub along the radial direction; and one or more bearings for supporting rotation of the plurality of fan blades about the longitudinal axis, the one or more bearings defining a DN value during rotation of the plurality of fan blades about the axial direction at the maximum rotational speed of at least 0.54 million and up to 1.65 million, and the one or more bearings including a ball bearing defining a fan bearing radius along the radial direction, a ratio of the hub radius to the fan bearing radius being less than 1.75; and a power gearbox, wherein the fan is driven by the core turbine engine through the Power gearbox. ### Claim 12 (depends on 11) The gas turbine engine of claim 11, wherein the one or more bearings define a DN value during operation of the fan at the maximum rotational speed of at least 0.72 million and up to 1.65 million. ### Claim 13 (depends on 11) The gas turbine engine of claim 11, wherein the fan further comprises a pitch change mechanism for changing a pitch of each of the plurality of fan blades, and wherein the one or more bearings are located outward from the pitch change mechanism along the radial direction. ### Claim 14 (depends on 11) The gas turbine engine of claim 11, wherein the one or more bearings include a plurality of bearings, and wherein the fan bearing radius is a radius of the innermost bearing along the radial direction. ### Claim 15 A gas turbine engine defining a radial direction and a longitudinal axis, the gas turbine engine comprising: a core turbine engine; and a fan mechanically coupled to the core turbine engine, the fan comprising a plurality of fan blades, each fan blade defining a base at an inner end along the radial direction; a hub configured to direct an airflow through the plurality of fan blades and covering the base of each of the plurality of fan blades, the hub defining a hub radius along the radial direction between the longitudinal axis and an outermost point of the hub along the radial direction; and one or more bearings for supporting rotation of the plurality of fan blades about the longitudinal axis, the one or more bearings including a ball bearing defining a fan bearing radius along the radial direction, a ratio of the hub radius to the fan bearing radius being less than 1.75; and a power gearbox, wherein the fan is driven by the core turbine engine through the power gearbox, wherein the gas turbine engine is configured to generate a maximum takeoff thrust, and wherein the maximum takeoff thrust is greater than 10,000 pounds and less than 30,000 pounds. ### Claim 16 (depends on 15) The gas turbine engine of claim 15, wherein the ratio of the hub radius to the fan bearing radius is greater than or equal to one and less than or equal to about 1.5, and wherein the maximum takeoff thrust is greater than 12,600 pounds and less than 27,500 pounds.