# US 12,110,120 B2 · Propulsion unit for an aircraft and method for mounting same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,110,120 B2 - Document ID: US12110120B2 - Status: Granted - Kind: B2 - Application number: 18/255,025 - Filed: 2021-12-01 - Published: 2024-01-25 - Granted: 2024-10-08 - Earliest claimed: 2020-12-07 - Assignees: Safran Nacelles - Applicants: Safran Nacelles - Inventors: Hazem Kioua; Thomas Marlay; Charles-Antoine Lampaert; Pierre-Alain Reboul - Web page: https://patentgrep.com/patent/US12110120B2 ## CPC - B64D 27/40: Arrangements for mounting power plants in aircraft - F02C 7/28: Arrangement of seals - B64D 27/14: within, or attached to, fuselages - B64D 29/04: associated with fuselages - B64D 29/06: Attaching of nacelles, fairings or cowlings - B64D 29/08: Inspection panels for power plants - F01D 25/243: {Flange connections; Bolting arrangements (F01D25/265 takes precedence)} - F01D 25/28: Supporting or mounting arrangements, e.g. for turbine casing - F02C 7/00: Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants (controlling F02C9/00) - F02C 7/04: Air intakes for gas-turbine plants or jet-propulsion plants - F02C 7/20: Mounting or supporting of plant; Accommodating heat expansion or creep - F05D 2220/323: for aircraft propulsion, e.g. jet engines - F05D 2230/60: Assembly methods - F05D 2230/70: Disassembly methods - F05D 2240/55: Seals - F05D 2260/30: Retaining components in desired mutual position - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN 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 propulsion unit for an aircraft includes a gas generator; an air inlet; and a sealing system inserted axially between the air inlet and the gas generator. The sealing system has at least: a compression ring with a first axial end configured for mechanical connection to one of the gas generator and the air inlet. The compression ring also has a second opposite axial end configured to be axially separated from the other of the gas generator and the air inlet by an annular space. An annular seal is mounted in the space and configured to be axially compressed by reduction of the axial dimension of said space. ## Claims ### Claim 1 A propulsion unit for an aircraft, the propulsion unit comprising: a gas generator having a longitudinal axis and comprising at least one compressor, a combustion chamber, and at least one turbine arranged one behind the other along said axis, a tubular air inlet arranged upstream of the gas generator with reference to flowing gases in operation, and an annular sealing system axially interposed between the air inlet and the gas generator, the sealing system being configured to provide a sealing between a downstream edge of the air inlet and an upstream edge of the gas generator, the edges being configured to be disjoint from each other, wherein the sealing system comprises: a compression ring comprising a first axial end to mechanically connect to a first element chose from the gas generator and the air inlet, and a second opposite axial end configured to be axially separated from a second element chosen from the gas generator and the air inlet by an annular space, said annular space having an axial dimension which is suitable to be reduced by bringing the compression ring closer to said second element, and an annular seal mounted in the space and configured to be axially compressed by reduction of the axial dimension of the space, wherein the second end of the compression ring comprises projecting clevises which are located opposite similar clevises of the corresponding edge and which are configured to allow the application of a force to reduce the axial dimension of said space. ### Claim 2 (depends on 1) The propulsion unit of claim 1, wherein the seal is configured to be compressed to an axial dimension of at least 5 mm and/or to a compression ratio of at least 25%. ### Claim 3 (depends on 1) The propulsion unit according to claim 1, wherein the seal comprises: at least one annular portion comprising an annular cavity having, in axial cross-section, a shape configured to be modified upon the compression of the seal, and/or at least one annular portion comprising a cylindrical bead configured to be engaged in the compression ring or one of the edges, and/or at least one annular sealing lip. ### Claim 4 (depends on 1) The propulsion unit according to claim 1, wherein the seal comprises an annular body of elastomeric or composite material and an annular sheet-metal extending to an internal periphery of the body. ### Claim 5 (depends on 1) The propulsion unit according to claim 1, wherein the first end of the compression ring comprises an annular flange configured to attach to a complementary annular flange of the corresponding edge. ### Claim 6 (depends on 1) The propulsion unit according to claim 1, wherein the devises comprise axially aligned orifices configured for a passage of screws, the screws being configured to be screwed so as to reduce the axial dimension of said space and to be removed during normal operation of the propulsion unit. ### Claim 7 (depends on 1) The propulsion unit according to claim 1, wherein said air inlet is arranged coaxially upstream of the gas generator. ### Claim 8 (depends on 1) A method for mounting the propulsion unit according to claim 1, the method comprising the steps of: a) positioning the sealing system coaxially with the second element, the second end of the ring facing the edge of said second element and the seal being mounted in said space, b) bringing the second end of the compression ring closer to the edge of the second element so as to reduce the axial dimension of the space for housing the seal and thereby exert an axial compression force of the seal, c) displacing the first element in a direction transverse with respect to a longitudinal axis of the second element, until the first and second elements are axially aligned and the first end of the ring is separated by a predetermined axial distance from the edge of the first element, d) suppressing the axial compression force of the seal so that an elastic return of the seal causes the suppression of the aforementioned axial distance, and e) attaching the first end of the compression ring to the edge of the first element. ### Claim 9 (depends on 8) The method according to claim 8, wherein the seal remains axially constrained in said space at the end of step d) and during step e). ### Claim 10 (depends on 8) The method according to claim 8, wherein the second end of the compression ring comprises projecting clevises which are located opposite similar clevises of the corresponding edge and which are configured to allow the application of a force to reduce the axial dimension of said space, and step b) is carried out using clamps resting axially on said clevises, or using screws passing through orifices in said clevises. ### Claim 11 (depends on 1) A method for dismounting the propulsion unit according to claim 1, comprising the steps of: f) disengaging the first end of the compression ring from the edge of the first element, g) bringing the second end of the compression ring closer to the edge of the second element so as to reduce the axial dimension of the space for housing the seal and thereby exert an axial compression force of the seal, h) displacing the first element in a direction transverse with respect to a longitudinal axis of the second element, until the first and second elements are misaligned, and i) suppressing the axial compression force of the seal. ### Claim 12 A propulsion unit for an aircraft, the propulsion unit comprising: a gas generator having a longitudinal axis and comprising at least one compressor, a combustion chamber, and at least one turbine arranged one behind the other along said axis, a tubular air inlet arranged upstream of the gas generator with reference to flowing gases in operation, and an annular sealing system axially interposed between the air inlet and the gas generator, the sealing system being configured to provide a sealing between a downstream edge of the air inlet and an upstream edge of the gas generator, the edges being configured to be disjoint from each other, wherein the sealing system comprises: a compression ring comprising a first axial end to mechanically connect to a first element chosen from the gas generator and the air inlet, and a second opposite axial end configured to be axially separated from a second element chosen from the gas generator and the air inlet by an annular space, said annular space having an axial dimension which is suitable to be reduced by bringing the compression ring closer to said second element, and an annular seal mounted in the space and configured to be axially compressed by reduction of the axial dimension of the space, wherein the seal comprises: at least one annular portion comprising an annular cavity having, in axial cross-section, a shape configured to be modified upon the compression of the seal, and/or at least one annular portion comprising a cylindrical bead configured to be engaged in the compression ring or one of the edges, and/or at least one annular sealing lip. ### Claim 13 A propulsion unit for an aircraft, the propulsion unit comprising: a gas generator having a longitudinal axis and comprising at least one compressor, a combustion chamber, and at least one turbine arranged one behind the other along said axis, a tubular air inlet arranged upstream of the gas generator with reference to flowing gases in operation, and an annular sealing system axially interposed between the air inlet and the gas generator, the sealing system being configured to provide a sealing between a downstream edge of the air inlet and an upstream edge of the gas generator, the edges being configured to be disjoint from each other, wherein the sealing system comprises: a compression ring comprising a first axial end to mechanically connect to a first element chosen from the gas generator and the air inlet, and a second opposite axial end configured to be axially separated from a second element chosen from the gas generator and the air inlet by an annular space, said annular space having an axial dimension which is suitable to be reduced by bringing the compression ring closer to said second element, and an annular seal mounted in the space and configured to be axially compressed by reduction of the axial dimension of the space, wherein the seal comprises an annular body of elastomeric or composite material and an annular sheet-metal extending to an internal periphery of the body.