# US 2014/0193239 A1 · Turbomachine shaft sealing arrangement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0193239 A1 - Document ID: US20140193239A1 - Status: Published application - Kind: A1 - Application number: 13/970,173 - Filed: 2013-08-19 - Published: 2014-07-10 - Earliest claimed: 2012-01-13 - Assignees: Cummins Inc. - Applicants: Cummins Ltd. - Inventors: Prabhu Ramasamy; Andrew Day - Web page: https://patentgrep.com/patent/US20140193239A1 ## CPC - F04D 29/10: Shaft sealings - F01D 25/186: {for sliding contact bearing} - F16C 33/6637: {with liquid lubricant} - F16C 33/76: of ball or roller bearings - F05D 2220/40: in turbochargers - F16C 19/184: {in O-arrangement} - F16C 27/045: {with a fluid film, e.g. squeeze film damping} - F16C 2360/24: Turbochargers - 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) - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A turbomachine with a rotary shaft supporting a turbine wheel is supported for rotation in a housing. The shaft extends through a bore in the housing and a bearing assembly being disposed in the bore. At least one end of the shaft has a primary seal and a secondary seal. The primary seal comprises a non-contact seal defined by an annular clearance between a first non-rotating seal element and a second seal element that rotates with the shaft. The primary seal is arranged to receive lubricating oil from the bearing assembly. An oil slinging feature is provided between the primary and secondary seals. ## Claims ### Claim 1 A turbomachine comprising: a shaft rotatable about a rotational axis; a turbine wheel provided at one end of the shaft for rotation about the rotational axis within a turbine housing; the shaft being supported for rotation in a bearing housing by a bearing assembly, the bearing housing having a bore through which the shaft extends, the bearing assembly being disposed in the bore; wherein at least one end of the shaft has a primary seal and a secondary seal, the primary seal comprising a non-contact seal defined by an annular clearance between a first non-rotating seal element and a second seal element that rotates with the shaft, the primary seal being arranged to receive lubricating oil from the bearing assembly, an oil slinging feature being provided between the primary and secondary seals. ### Claim 2 (depends on 1) A turbomachine according to claim 1, wherein the primary seal is disposed at an axial location between the bearing assembly and the secondary seal. ### Claim 3 (depends on 1) A turbomachine according to claim 1, wherein the primary seal is defined at one end of the bearing assembly. ### Claim 4 (depends on 1) A turbomachine according to claim 1 wherein the first seal element of the primary seal is fixed relative to the bearing housing. ### Claim 5 (depends on 4) A turbomachine according to claim 4, wherein the first seal element is defined by an axial thrust bearing. ### Claim 6 (depends on 4) A turbomachine according to claim 4, wherein the first seal element is defined by a projection from the bearing housing. ### Claim 7 (depends on 1) A turbomachine according to claim 1, wherein the annular clearance of the primary seal extends in the axial direction only. ### Claim 8 (depends on 1) A turbomachine according to claim 1 wherein the annular clearance has a radial depth of 0.05 mm to 0.15 mm. ### Claim 9 (depends on 8) A turbomachine according to claim 8, wherein the annular clearance has a radial depth of 0.05 to 0.082 mm. ### Claim 10 (depends on 8) A turbomachine according to claim 8, wherein the annular clearance has a radial depth of 0.075 to 0.125 mm. ### Claim 11 (depends on 1) A turbomachine according to claim 1, wherein the second seal element is defined by the shaft or by a component fixed to the shaft. ### Claim 12 (depends on 1) A turbomachine according to claim 1, wherein the secondary seal comprises one or more piston seals that are supported on a surface of the bearing housing and extend radially into a corresponding annular groove defined in the shaft. ### Claim 13 (depends on 1) A turbomachine according to claim 1, wherein the bearing assembly comprises a squeeze film damper with a radial clearance between its outer surface and a surface that defines the bore in the bearing housing. ### Claim 14 (depends on 1) A turbomachine according to claim 1, wherein the bearing assembly comprises a rolling bearing element. ### Claim 15 (depends on 14) A turbomachine according to claim 14, wherein the bearing assembly comprises a cartridge having an inner ring, an outer ring and at least one intermediate rolling bearing element. ### Claim 16 (depends on 15) A turbomachine according to claim 15, wherein the primary seal is provided between the inner and outer rings. ### Claim 17 (depends on 1) A turbomachine according to claim 1, wherein the oil slinging feature is a dedicated oil slinger that is integrally formed with the shaft or defined on a component that is fixed to the shaft. ### Claim 18 (depends on 1) A turbomachine according to claim 1, wherein a compressor connected to the opposite end of the shaft to the turbine for rotation about said axis within a compressor housing, thereby forming a turbocharger.