# US 9,435,347 B2 · Turbopump, in particular for feeding rocket engines > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,435,347 B2 - Document ID: US9435347B2 - Status: Granted - Kind: B2 - Application number: 13/820,308 - Filed: 2011-08-31 - Published: 2013-09-05 - Granted: 2016-09-06 - Earliest claimed: 2010-09-03 - Assignees: Snecma - Applicants: Francois Danguy; Laurent Fabbri; Sebastien Guingo - Inventors: Francois Danguy; Laurent Fabbri; Sebastien Guingo - Web page: https://patentgrep.com/patent/US9435347B2 ## CPC - F04D 29/047: hydrostatic; hydrodynamic - F02K 9/46: using pumps - F04D 7/02: of centrifugal type - F04D 13/04: the pump being fluid driven - F04D 29/049: Roller bearings - F16C 21/00: Combinations of sliding-contact bearings with ball or roller bearings, for exclusively rotary movement (F16C17/24, F16C19/52 take precedence) - F16C 2360/24: Turbochargers - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS ## Abstract A turbopump for feeding a low-thrust rocket engine comprises a pump, a turbine, and a common rotary shaft connected to the pump and to the turbine. First and second bearings closer respectively to the pump and to the turbine serve to support the common shaft. The second bearing is a hydrodynamic bearing connected to a gas supply source, and the turbopump also includes at least one dynamic sealing gasket around the shaft and interposed between the first and second bearings. ## Claims ### Claim 1 A turbopump, comprising: a propellant pump; a turbine; a common rotary shaft connected to said propellant pump and to said turbine; a first bearing and a second bearing, the first and second bearings supporting said common rotary shaft, said first bearing being closer than the second bearing to the propellant pump, and said second bearing being closer than the first bearing to the turbine; and at least one dynamic sealing gasket around the common rotary shaft interposed between said first and second bearings, wherein said second bearing is a hydrodynamic bearing connected to a gas supply source so that no seal is interposed between the second bearing and the turbine. ### Claim 2 (depends on 1) The turbopump according to claim 1, wherein said propellant pump is a cryogenic fluid pump. ### Claim 3 (depends on 1) The turbopump according to claim 1, wherein said dynamic sealing gasket is connected to a source of inert fluid. ### Claim 4 (depends on 1) The turbopump according to claim 1, wherein said first bearing is connected to the propellant pump to lubricate the first bearing with fluid coming from the propellant pump. ### Claim 5 (depends on 4) The turbopump according to claim 4, wherein said first bearing is a rolling bearing. ### Claim 6 (depends on 4) The turbopump according to claim 4, further comprising: an auxiliary pump to exhaust said fluid from the first bearing. ### Claim 7 (depends on 4) The turbopump according to claim 4, wherein said common rotary shaft adopts a rest position in which a facial contact seal is closed around the common rotary shaft, and is movable in a movement axially from said rest position to a working position in which said facial contact seal is open, the movement being against a return force exerted by at least one resilient element. ### Claim 8 (depends on 7) The turbopump according to claim 7, wherein said propellant pump presents an axial admission passage situated at an end of said propellant pump that is remote from said first bearing, and said working position is situated towards the propellant pump relative to said rest position. ### Claim 9 (depends on 8) The turbopump according to claim 8, wherein, in said working position, an axial element secured to the common rotary shaft but free to rotate relative to the common rotary shaft comes into abutment, towards the propellant pump, against a stator secured to a casing of the turbopump. ### Claim 10 (depends on 8) The turbopump according to claim 8, wherein, in said rest position, an axial element secured to the common rotary shaft comes into abutment, towards the turbine, against a stator secured to a casing of the turbopump. ### Claim 11 (depends on 1) The turbopump according to claim 1, wherein said gas supply source for the hydrodynamic bearing is the turbine. ### Claim 12 (depends on 1) An assembly, comprising: the turbopump according to claim 1; and a propulsion chamber, wherein said gas supply source for the hydrodynamic bearing is an outlet from a regenerative circuit of the propulsion chamber. ### Claim 13 (depends on 1) A rocket engine, comprising: at least one propulsion chamber; and the turbopump according to claim 1 to feed at least one propellant to said at least one propulsion chamber. ### Claim 14 (depends on 12) A rocket engine, comprising: the assembly according to claim 12. ### Claim 15 (depends on 7) A method of using the turbopump according to claim 7, wherein the first bearing is lubricated by the fluid coming from the propellant pump, the method comprising: preventing, with said facial contact seal, said lubricating fluid from passing towards the dynamic sealing gasket and the second bearing when the turbopump is stopped; and opening said facial contact seal by axial movement of the common rotary shaft when the turbopump is started.