# US 10,371,162 B2 · Integrally bladed fan rotor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,162 B2 - Document ID: US10371162B2 - Status: Granted - Kind: B2 - Application number: 15/286,078 - Filed: 2016-10-05 - Published: 2018-04-05 - Granted: 2019-08-06 - Earliest claimed: 2016-10-05 - Assignees: Pratt & Whitney Canada Corp. - Applicants: Pratt & Whitney Canada Corp. - Inventors: Andreas Eleftheriou; Richard Ivakitch; David Menheere - Web page: https://patentgrep.com/patent/US10371162B2 ## CPC - F04D 29/329: {Details of the hub} - F01D 5/34: Rotor-blade aggregates of unitary construction {, e.g. formed of sheet laminae; (discs formed of sheet laminae F01D5/028; ceramic materials F01D5/284, composite materials F01D5/282)} - F01D 11/008: {by spacer elements between the blades, e.g. independent interblade platforms} - F02K 3/06: with front fan - F04D 19/002: {Axial flow fans} - F04D 29/321: {for axial flow compressors} - F04D 29/324: {Blades} - F04D 29/542: {Bladed diffusers (fixing blades to stators F01D9/042)} - F04D 29/646: {Mounting or removal of fans} - F05D 2220/32: in gas turbines - F05D 2220/36: specially adapted for the fan of turbofan engines - F05D 2240/12: Fluid guiding means, e.g. vanes - F05D 2240/80: Platforms for stationary or moving blades - F05D 2260/30: Retaining components in desired mutual position - F05D 2260/36: by a form fit connection, e.g. by interlocking - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - 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) - 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 An integrally bladed fan (IBF) rotor of a gas turbine engine. The IBF rotor includes a hub and a plurality of fan blades extending radially outwardly from the hub and integral therewith. The hub has a fan attachment flange disposed at an end of the hub on a trailing edge side thereof for mounting a booster rotor to a trailing edge side of the fan. The fan attachment flange is disposed at a radial distance from a longitudinal center axis of the integrally bladed fan rotor. The hub has an outer hub surface disposed radially inward from the radial distance of the fan attachment flange. ## Claims ### Claim 1 An integrally bladed fan rotor of a gas turbine engine, comprising a hub and a plurality of fan blades extending radially outwardly from the hub and integral therewith, the hub having a fan attachment flange disposed at an end of the hub on a trailing edge side thereof for mounting a booster rotor to a trailing edge side of the integrally bladed fan rotor, the fan attachment flange disposed at a radial distance from a longitudinal center axis of the integrally bladed fan rotor, the hub defining an outer peripheral surface extending circumferentially about of-the hub and disposed radially inward from the radial distance of the fan attachment flange, the plurality of fan blades entirely disposed radially outwardly from the outer peripheral surface of the hub. ### Claim 2 (depends on 1) The integrally bladed fan rotor as defined in claim 1, further comprising a plurality of gas path inserts, each gas path insert being spaced radially outward from the outer peripheral surface and extending circumferentially between adjacent fan blades of the plurality of fan blades, each gas path insert having an outer insert surface defining an outer gas path surface between the adjacent fan blades of the plurality of fan blades. ### Claim 3 (depends on 2) The integrally bladed fan rotor as defined in claim 2, wherein each gas path insert engages side surfaces of the adjacent fan blades of the plurality of fan blades and defines an inner portion of each fan blade of the plurality of fan blades radially extending between the outer peripheral surface and each gas path insert, and an outer portion of each fan blade of the plurality of fan blades radially extending between each gas path insert and a tip of the plurality of fan blades, at least the outer portion of each fan blade of the plurality of fan blades having an airfoil shape. ### Claim 4 (depends on 3) The integrally bladed fan rotor as defined in claim 3, wherein only the outer portion of each fan blade of the plurality of fan blades has the airfoil shape. ### Claim 5 (depends on 4) The integrally bladed fan rotor as defined in claim 4, wherein the inner portion of each fan blade of the plurality of fan blades includes a tuneable neck portion. ### Claim 6 (depends on 3) The integrally bladed fan rotor as defined in claim 3, wherein each fan blade of the plurality of fan blades includes a retention member protruding outwardly from a corresponding side surface of the plurality of fan blades, the retention member engaging an end of each gas path insert. ### Claim 7 (depends on 1) The integrally bladed fan rotor as defined in claim 1, wherein the hub includes a plurality of circumferentially-spaced stubs extending radially outwardly from the outer peripheral surface, a radially-inner end of each fan blade of the plurality of fan blades being integrally attached to a corresponding stub by being welded thereto to define a weld line, the weld line being disposed radially inward from the fan attachment flange. ### Claim 8 (depends on 1) The integrally bladed fan rotor as defined in claim 1, wherein the fan attachment flange has a plurality of fastener holes extending therethrough, at least one of the fastener holes being disposed circumferentially between adjacent fan blades of the plurality of fan blades. ### Claim 9 A gas turbine engine, comprising: a rotatable booster stage having alternating rows of booster stator vanes and booster rotor blades, the booster rotor blades attached to a booster attachment flange disposed at an end of the booster stage on a leading edge side thereof upstream of the rows of booster stator vanes and booster rotor blades; and an integrally bladed fan rotor disposed upstream of the booster stage, the fan rotor comprising a hub and a plurality of fan blades extending radially outwardly from the hub and integral therewith, the hub having a fan attachment flange disposed at an end of the hub on a trailing edge side thereof and mounted to the booster attachment flange, the fan attachment flange disposed at a radial distance from a longitudinal center axis of the gas turbine engine, the hub defining an outer peripheral surface extending circumferentially about the hub and disposed radially inward from the fan attachment flange, the plurality of fan blades entirely disposed radially outwardly from the outer peripheral surface of the hub. ### Claim 10 (depends on 9) The gas turbine engine as defined in claim 9, further comprising a plurality of gas path inserts, each gas path insert being spaced radially outward from the outer peripheral surface and extending circumferentially between adjacent fan blades of the plurality of fan blades, each gas path insert having an outer insert surface defining an outer gas path surface between the adjacent fan blades of the plurality of fan blades. ### Claim 11 (depends on 10) The gas turbine engine as defined in claim 10, wherein each gas path insert engages side surfaces of the adjacent fan blades of the plurality of fan blades and defines an inner portion of each fan blade of the plurality of fan blades radially extending between the outer peripheral surface and each gas path insert, and an outer portion of each fan blade of the plurality of fan blades radially extending between each gas path insert and a tip of the fan blade, at least the outer portion of each fan blade of the plurality of fan blades having an airfoil shape. ### Claim 12 (depends on 11) The gas turbine engine as defined in claim 11, wherein only the outer portion of each fan blade of the plurality of fan blades has the airfoil shape. ### Claim 13 (depends on 10) The gas turbine engine as defined in claim 10, wherein each gas path insert dampens vibration of the plurality of fan blades during operation of the engine. ### Claim 14 (depends on 11) The gas turbine engine as defined in claim 11, wherein each fan blade of the plurality of fan blades includes a retention member protruding outwardly from a corresponding side surface of the fan blade, the retention member engaging an end of each gas path insert. ### Claim 15 (depends on 9) The gas turbine engine as defined in claim 9, wherein the hub includes a plurality of circumferentially-spaced stubs extending radially outwardly from the outer peripheral surface, a radially-inner end of each fan blade of the plurality of fan blades being integrally attached to a corresponding stub by being welded thereto to define a weld line, the weld line being disposed radially inward from the fan attachment flange. ### Claim 16 (depends on 9) The gas turbine engine as defined in claim 9, wherein the fan attachment flange has a plurality of fastener holes extending therethrough, at least one of the fastener holes being disposed circumferentially between adjacent fan blades of the plurality of fan blades. ### Claim 17 A method of manufacturing an integrally bladed fan rotor, comprising: integrally forming a hub and a plurality of fan blades extending radially outwardly from the hub, the hub having a circumferential fan attachment flange disposed at an end of the hub on a trailing edge side thereof; and an outer peripheral surface extending circumferentially about of-the hub and disposed radially inward from the fan attachment flange, the plurality of fan blades entirely disposed radially outwardly from the outer peripheral surface of the hub. ### Claim 18 (depends on 17) The method of claim 17, wherein forming the outer peripheral surface includes removing material from the hub to decrease a radial thickness of the hub. ### Claim 19 (depends on 17) The method of claim 17, wherein forming the outer peripheral surface includes casting or forging the hub having an outer diameter corresponding to a desired outer diameter of the outer peripheral surface. ### Claim 20 (depends on 17) The method of claim 17, wherein integrally forming the hub and the plurality of fan blades includes welding the plurality of fan blades to circumferentially spaced stubs extending radially outwardly from the outer peripheral surface of the hub, a weld line being formed at a junction between each fan blade of the plurality of fan blades and a corresponding stub, the weld lines being disposed radially inward from the fan attachment flange.