# US 2021/0277937 A1 · High performance air journal bearing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0277937 A1 - Document ID: US20210277937A1 - Status: Published application - Kind: A1 - Application number: 16/808,771 - Filed: 2020-03-04 - Published: 2021-09-09 - Earliest claimed: 2020-03-04 - Assignees: The Boeing Company - Applicants: The Boeing Company - Inventors: Mohamed Elbibary; Zachary G. Brown - Web page: https://patentgrep.com/patent/US20210277937A1 ## CPC - F16C 17/024: {with flexible leaves to create hydrodynamic wedge, e.g. radial foil bearings} - B22F 5/106: {Tube or ring forms} - B22F 10/00: Additive manufacturing of workpieces or articles from metallic powder (apparatus or devices therefor B22F12/00) - B22F 10/28: Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] - B28B 1/001: {Rapid manufacturing of 3D objects by additive depositing, agglomerating or laminating of material (selective deposition modelling of metallic powder B22F10/00; rapid manufacturing of 3D objects in general and in particular of plastics B29C64/00)} - B33Y 10/00: Processes of additive manufacturing - B33Y 70/10: Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials - C22C 29/00: Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides {(C22C26/00 takes precedence)} - F16C 43/02: Assembling sliding-contact bearings - B22F 2999/00: Aspects linked to processes or compositions used in powder metallurgy - B33Y 80/00: Products made by additive manufacturing - F16C 2206/06: Composite carbon material, e.g. carbon fibre reinforced carbon (C/C) - F16C 2206/40: Ceramics, e.g. carbides, nitrides, oxides, borides of a metal - F16C 2220/20: by sintering pulverised material, e.g. powder metallurgy - F16C 2360/24: Turbochargers - Y02P 10/25: Process efficiency - Y10T 29/49636: Process for making bearing or component thereof - Y10T 29/49696: Mounting - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER - B28B: SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER (foundry moulding B22C; working stone or stone-like material B28D; shaping of substances in a plastic state, in general B29C; making layered products not composed wholly of these substances B32B) - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING - C22C: ALLOYS (treatment of alloys C21D, C22F) - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An air journal bearing for a rotatable shaft of a turbomachine includes a journal sleeve having an inner cylindrical surface and a central axis defining longitudinal and radial directions, a top foil disposed radially inboard of the journal sleeve and configured to receive the rotatable shaft, and a bump foil disposed between the top foil and the journal sleeve and configured to bias at least a portion of the top foil against an outer surface of the rotatable shaft. At least one of the bump foil and a radially extending segment of the top foil is formed contiguous with the inner cylindrical surface. The journal sleeve, the top foil and the bump foil may be formed as a single piece made of selectively sintered ceramic-metal powder. ## Claims ### Claim 1 An air journal bearing for a rotatable shaft of a turbomachine, comprising: a journal sleeve having an inner cylindrical surface and a central axis defining longitudinal and radial directions; a top foil disposed radially inboard of the journal sleeve and configured to receive the rotatable shaft; and a bump foil disposed between the top foil and the journal sleeve and configured to bias at least a portion of the top foil against an outer surface of the rotatable shaft; wherein at least one of the bump foil and a radially extending segment of the top foil is formed contiguous with the inner cylindrical surface, and wherein the journal sleeve, the top foil and the bump foil are formed as a single piece by additive manufacturing. ### Claim 2 (canceled) ### Claim 3 (depends on 1) An air journal bearing according to claim 1, wherein the additive manufacturing comprises selective laser sintering. ### Claim 4 (depends on 1) An air journal bearing according to claim 1, wherein the journal sleeve, the top foil and the bump foil are made of selectively sintered ceramic-metal powder. ### Claim 5 (depends on 1) An air journal bearing according to claim 1, wherein the journal sleeve, the top foil and the bump foil are made of carbon fiber. ### Claim 6 (depends on 1) An air journal bearing according to claim 1, wherein the top foil is contiguous with the bump foil at at least one location on the top foil. ### Claim 7 (depends on 1) An air journal bearing according to claim 1, wherein the top foil and the bump foil are constrained against rotation with respect to the journal sleeve. ### Claim 8 (depends on 1) An air journal bearing according to claim 1, wherein the top foil and the bump foil define a plurality of first longitudinal channels therebetween and the bump foil and the inner cylindrical surface define a plurality of second longitudinal channels therebetween. ### Claim 9 (depends on 8) An air journal bearing according to claim 8, wherein the bump foil and the radially extending segment of the top foil are formed contiguous with the inner cylindrical surface. ### Claim 10 (depends on 1) An air journal bearing according to claim 1, wherein each of the top foil and the bump foil extends substantially along an entirety of the circumference of the inner cylindrical surface. ### Claim 11 An air journal bearing for a rotatable shaft of an air handling machine, comprising: a journal sleeve having an inner cylindrical surface and a central axis defining longitudinal and radial directions; a top foil disposed radially inboard of the journal sleeve and configured to receive the rotatable shaft; and a bump foil disposed between the top foil and the journal sleeve and configured to bias at least a portion of the top foil against an outer surface of the rotatable shaft; wherein the journal sleeve, the top foil and the bump foil are formed as a single piece made of selectively sintered ceramic-metal powder, and wherein at least one of the bump foil and a radially extending segment of the top foil is formed contiguous with the inner cylindrical surface. ### Claim 12 (depends on 11) An air journal bearing according to claim 11, wherein the top foil is contiguous with the bump foil at at least one location on the top foil. ### Claim 13 (depends on 11) An air journal bearing according to claim 11, wherein the top foil and the bump foil are constrained against rotation with respect to the journal sleeve. ### Claim 14 (depends on 11) An air journal bearing according to claim 11, wherein the top foil and the bump foil define a plurality of first longitudinal channels therebetween and the bump foil and the inner cylindrical surface define a plurality of second longitudinal channels therebetween. ### Claim 15 (depends on 14) An air journal bearing according to claim 14, wherein the bump foil and the radially extending segment of the top foil are formed contiguous with the inner cylindrical surface. ### Claim 16 (depends on 11) An air journal bearing according to claim 11, wherein each of the top foil and the bump foil extends substantially along an entirety of the circumference of the inner cylindrical surface. ### Claim 17 A method of manufacturing a one-piece air journal bearing for a rotatable shaft of a turbomachine, comprising: presenting a plurality of successive deposition layers of a ceramic-metal powder comprising a mixture of ceramic powder and metal powder, wherein the ceramic and metal powders are sinterable by absorption of laser energy at first and second wavelengths, respectively; and after the presenting of each deposition layer, laser scanning a respective pattern on each deposition layer, using a respective combination of the first and second wavelengths, to produce a respective product layer of the one-piece air journal bearing made of selectively sintered ceramic and/or selectively sintered metal and corresponding to the respective pattern; wherein an accumulation of the respective product layers produces the one-piece air journal bearing comprising: a journal sleeve having an inner cylindrical surface; a top foil disposed radially inboard of the journal sleeve and configured to receive the rotatable shaft; and a bump foil disposed between the top foil and the journal sleeve and configured to bias at least a portion of the top foil against an outer surface of the rotatable shaft; wherein at least one of the bump foil and a radially extending segment of the top foil is formed contiguous with the inner cylindrical surface. ### Claim 18 (depends on 17) A method of manufacturing according to claim 17, wherein the ceramic-metal powder includes a buffer powder having a melting point higher than respective melting points of the ceramic powder and the metal powder. ### Claim 19 (depends on 17) A method of manufacturing according to claim 17, wherein the laser scanning utilizes the first wavelength at respective first portions of each respective pattern to sinter the ceramic powder thereat and the second wavelength at respective second portions of each respective pattern to sinter the metal powder thereat. ### Claim 20 (depends on 17) A method of manufacturing according to claim 17, wherein a ratio of sintered ceramic to sintered metal per unit volume varies radially for at least one of the journal sleeve, the top foil and the bump foil.