# US 2013/0156591 A1 · Energy absorbent fan blade spacer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0156591 A1 - Document ID: US20130156591A1 - Status: Published application - Kind: A1 - Application number: 13/328,668 - Filed: 2011-12-16 - Published: 2013-06-20 - Earliest claimed: 2011-12-16 - Assignees: United Technologies Corporation - Inventors: Phillip Alexander - Web page: https://patentgrep.com/patent/US20130156591A1 ## CPC - F01D 5/323: {Locking of axial insertion type blades by means of a key or the like parallel to the axis of the rotor} - F01D 5/3092: {Protective layers between blade root and rotor disc surfaces, e.g. anti-friction layers (F01D5/288 takes precedence)} - F05D 2250/184: sinusoidal - F05D 2260/941: particularly aimed at mechanical or thermal stress reduction - F05D 2300/501: Elasticity - F05D 2300/611: Coating - 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 ## Abstract A gas turbine engine fan assembly includes a rotor disk, a fan blade and a spacer. The rotor disk includes a longitudinally extending slot with a first spacer contact surface. The fan blade includes a root with a second spacer contact surface arranged within the slot. The spacer includes a leaf spring backbone and a compliant member. The leaf spring backbone includes one or more root contact segments connected longitudinally to one or more slot contact segments. A first of the root contact segments contacts the second spacer contact surface, and a first of the slot contact segments contacts the first spacer contact surface. The compliant member is radially between the first spacer contact surface and the first root contact segment, and radially between the second spacer contact surface and the first slot contact segment. ## Claims ### Claim 1 A gas turbine engine fan assembly, comprising: a rotor disk comprising a longitudinally extending slot comprising a first spacer contact surface; a fan blade comprising a root arranged within the slot, the root comprising a second spacer contact surface; a spacer comprising leaf spring backbone comprising a root contact segment longitudinally between a first slot contact segment and a second slot contact segment, wherein the root contact segment contacts the second spacer contact surface, and the first and the second slot contact segments contact the first spacer contact surface; and a compliant member radially between the first spacer contact surface and the root contact segment, and radially between the second spacer contact surface and the first and the second slot contact segments. ### Claim 2 (depends on 1) The fan assembly of claim 1, wherein the leaf spring backbone preloads sidewalls of the root against respective sidewalls of the slot. ### Claim 3 (depends on 1) The fan assembly of claim 1, wherein the leaf spring backbone comprises a laterally elongated cross-sectional geometry. ### Claim 4 (depends on 3) The fan assembly of claim 3, wherein at least one of the root contact segment, the first slot contact segment and the second slot contact segment extends radially between a first surface with a substantially flat cross-sectional geometry and a second surface with a curved cross-sectional geometry that contacts the compliant member. ### Claim 5 (depends on 1) The fan assembly of claim 1, wherein the leaf spring backbone further comprises a first intermediate segment connected longitudinally between the root contact segment and the first slot contact segment, and a second intermediate segment connected longitudinally between the root contact segment and the second slot contact segment, and wherein at least one of the first and the second intermediate segments are encapsulated within the compliant member. ### Claim 6 (depends on 5) The fan assembly of claim 5, wherein at least one of the first intermediate segment and the second intermediate segment comprises one of a lens and elliptical cross-sectional geometry. ### Claim 7 (depends on 1) The fan assembly of claim 1, wherein the compliant member extends laterally between the leaf spring backbone and a first side of the fan blade spacer, and laterally between the leaf spring backbone and a second side of the fan blade spacer. ### Claim 8 (depends on 1) The fan assembly of claim 1, wherein the leaf spring backbone comprises at least one of a metallic material and a carbon composite material. ### Claim 9 (depends on 1) The fan assembly of claim 1, wherein the compliant member comprises at least one of an elastomeric material, a viscoelastic composite material and a plastically crushable material. ### Claim 10 (depends on 1) The fan assembly of claim 1, wherein the leaf spring backbone further comprises a second root contact segment connected longitudinally between the second slot contact segment and a third slot contact segment, and wherein the compliant member is radially between the first spacer contact surface and the second root contact segment, and radially between the second spacer contact surface and the third slot contact segment. ### Claim 11 A gas turbine engine fan assembly, comprising: a rotor disk comprising a longitudinally extending slot comprising a first spacer contact surface; a fan blade comprising a root arranged within the slot, the root comprising a second spacer contact surface; a spacer comprising a leaf spring backbone comprising a slot contact segment longitudinally between a first root contact segment and a second root contact segment, wherein the slot contact segment contacts the first spacer contact surface, and the first and the second root contact segments contact the second spacer contact surface; and a compliant member radially between the second spacer contact surface and the slot contact segment, and radially between the first spacer contact surface and the first and the second root contact segments. ### Claim 12 (depends on 11) The fan assembly of claim 11, wherein the leaf spring backbone preloads sidewalls of the root against respective sidewalls of the slot. ### Claim 13 (depends on 11) The fan assembly of claim 11, wherein the leaf spring backbone comprises a laterally elongated cross-sectional geometry. ### Claim 14 (depends on 13) The fan assembly of claim 13, wherein at least one of the root contact segment, the first slot contact segment and the second slot contact segment extends radially between a first surface with a substantially flat cross-sectional geometry and a second surface with a curved cross-sectional geometry that contacts the compliant member. ### Claim 15 (depends on 11) The fan assembly of claim 11, wherein the leaf spring backbone further comprises a first intermediate segment connected longitudinally between the slot contact segment and the first root contact segment, and a second intermediate segment connected longitudinally between the slot contact segment and the second root contact segment, and wherein at least one of the first and the second intermediate segments are encapsulated within the compliant member. ### Claim 16 (depends on 15) The fan assembly of claim 15, wherein at least one of the first intermediate segment and the second intermediate segment comprises one of a lens and elliptical cross-sectional geometry. ### Claim 17 (depends on 11) The fan assembly of claim 11, wherein the compliant member extends laterally between the leaf spring backbone and a first side of the fan blade spacer, and laterally between the leaf spring backbone and a second side of the fan blade spacer. ### Claim 18 (depends on 11) The fan assembly of claim 11, wherein the leaf spring backbone comprises at least one of a metallic material and a carbon composite material. ### Claim 19 (depends on 11) The fan assembly of claim 11, wherein the compliant member comprises at least one of an elastomeric material, a viscoelastic composite material and a plastically crushable material. ### Claim 20 (depends on 11) The fan assembly of claim 11, wherein the leaf spring backbone further comprises a second slot contact segment connected longitudinally between the second root contact segment and a third root contact segment, and wherein the compliant member is radially between the second spacer contact surface and the second slot contact segment, and radially between the first spacer contact surface and the third root contact segment.