# US 2016/0258309 A1 · Seal for jet engine mid-turbine frame > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0258309 A1 - Document ID: US20160258309A1 - Status: Published application - Kind: A1 - Application number: 15/032,024 - Filed: 2015-01-23 - Published: 2016-09-08 - Earliest claimed: 2014-01-28 - Assignees: United Technologies Corporation - Applicants: United Technologies Corporation - Inventors: John E. Wilber - Web page: https://patentgrep.com/patent/US20160258309A1 ## CPC - F01D 11/005: {Sealing means between non relatively rotating elements} - F01D 5/18: Hollow blades, {i.e. blades with cooling or heating channels or cavities (structure of hollow blades in general F01D5/147)}; Heating, heat-insulating or cooling means on blades - F01D 9/041: {using blades (F01D5/148 takes precedence)} - F01D 25/12: Cooling - F01D 25/162: {Bearing supports} - F05D 2220/323: for aircraft propulsion, e.g. jet engines - F05D 2240/12: Fluid guiding means, e.g. vanes - F05D 2260/201: by impingement of a fluid - F05D 2270/3062: of the auxiliary fluid for heating or cooling purposes - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - 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 mid-turbine frame (MTF”) for a jet engine is disclosed and comprises a duct that extends between a high pressure turbine (“HPT”) and a low pressure turbine (“LPT”), the duct comprising a plurality of segments that together form an outer annular structure and an inner annular structure, the inner annular structure situated radially inward of the outer annular structure, and/or a plurality of vanes that extend radially outward from the inner annular structure toward the outer annular structure, each vane comprising a channel. Each segment may be coupled to an adjacent segment by a seal. ## Claims ### Claim 1 A seal comprising: a male seal structure having a body and a protruding member extending away from the body; a receiving member having an aperture configured to receive the protruding member; a fastener configured to be coupled to the protruding member to retain the protruding member in contact with the receiving member. ### Claim 2 (depends on 1) The seal of claim 1, wherein the receiving member is coupled to a radially outward portion of a first segment that forms a portion of an annular structure and the male seal structure is coupled to a radially inward portion of the first segment. ### Claim 3 (depends on 2) The seal of claim 2, wherein the protruding member extends radially outward through the first segment. ### Claim 4 (depends on 2) The seal of claim 2, further comprising a tortuous gutter, the tortuous gutter comprising a narrow passage formed between the protruding member, a tenon, and a perforated structure. ### Claim 5 (depends on 2) The seal of claim 2, wherein the seal is configured to permit cooling air to flow into a hot gas path formed within a duct. ### Claim 6 (depends on 6) The seal of claim 6, wherein the tortuous gutter is configured to permit cooling air to flow into a hot gas path formed within a duct. ### Claim 7 A mid-turbine frame (“MTF”) for a jet engine comprising: a duct that extends between a high pressure turbine (“HPT”) and a low pressure turbine (“LPT”), the duct comprising a plurality of segments that together form an outer annular structure and an inner annular structure, wherein the inner annular structure is situated radially inward of the outer annular structure, wherein each segment comprising the outer annular structure includes a first tenon that defines a first axial terminus of each segment and a second tenon that defines a second axial terminus of each segment. ### Claim 8 (depends on 7) The MTF of claim 7, further comprising a plurality of vanes that extend radially outward from the inner annular structure toward the outer annular structure, each vane comprising a channel. ### Claim 9 (depends on 7) The MTF of claim 7, wherein each segment comprising the inner annular structure includes a third tenon that defines a third axial terminus of each segment and a fourth tenon that defines a fourth axial terminus of each segment. ### Claim 10 (depends on 7) The MTF of claim 7, wherein the first tenon is joined to the second tenon by a seal that clamps the first tenon and the second tenon together. ### Claim 11 (depends on 8) The MTF of claim 8, wherein the third tenon is joined to the fourth tenon by a seal that clamps the third tenon and the fourth tenon together. ### Claim 12 (depends on 7) The MTF of claim 7, wherein the duct defines a hot gas path between the HPT and the LPT. ### Claim 13 (depends on 7) The MTF of claim 7, further comprising a perforated structure that is disposed radially outward of the outer annular structure. ### Claim 14 (depends on 13) The MTF of claim 13, wherein each of a plurality of perforations in the perforated structure are configured to permit cooling air to flow into and over the outer annular structure. ### Claim 15 (depends on 7) The MTF of claim 7, further comprising a slot that extends between a channel formed in a first segment and a seal that clamps a second segment to the first segment. ### Claim 16 (depends on 15) The MTF of claim 15, wherein the slot is configured to relay cooling air through the seal and into a hot gas path within the duct. ### Claim 17 (depends on 7) The MTF of claim 7, further comprising a seal that includes a tortuous gutter that is configured to permit cooling air to flow into a hot gas path within the duct. ### Claim 18 (depends on 17) The MTF of claim 17, wherein the tortuous gutter comprises a narrow passage between a first member of the seal, the first tenon, and a perforated structure, which collectively form a passage through which air may flow.