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US 11,236,705 B2Granted
Gaseous fuel mixer assembly for engine and engine system operating method
AssigneeCaterpillar Inc.
InventorDavid Yu Zhang Chang
Life of this patent
Estimating the term…
Abstract
A gaseous fuel mixer assembly for an engine includes a mixer housing forming gas delivery openings, and positioned to extend across a flow path formed by an intake conduit for the engine. A spool valve is within a central bore in the mixer housing and includes gas distribution openings selectively connectable to the gas delivery openings by moving the spool valve within the mixer housing using a piezoelectric actuator coupled with the spool valve by way of a pivot arm. Sealing lands of the spool valve are in an alternating arrangement with the gas distribution openings, such that at the closed position the sealing lands block the gas distribution openings from the gas delivery openings, and at the open position the respective openings are fluidly connected.
Claims20
A gaseous fuel mixer assembly for an engine comprising:
- a mixer housing defining a longitudinal axis and including an inner housing surface forming a central bore, an outer housing surface, and gas delivery openings fluidly connected to the central bore and extending to the outer housing surface;
- the gas delivery openings form gas outlet locations having a circumferential distribution and an axial distribution in the outer housing surface, and gas inlet locations having an axial distribution in the inner housing surface;
- a spool valve within the central bore and including an inner valve surface forming a gas supply passage, an outer valve surface, gas distribution openings fluidly connected to the gas supply passage and extending to the outer valve surface, and sealing lands extending circumferentially around the longitudinal axis;
- a spool valve electrical actuator coupled with the spool valve to move the spool valve in axial directions between an open position and a closed position relative to the gas inlet locations;
- and the sealing lands are in an alternating arrangement with the gas distribution openings, relative to the longitudinal axis, and have an axial distribution matched to the axial distribution of the gas inlet locations, such that at the closed position the sealing lands block the gas distribution openings from the gas delivery openings, and at the open position the gas distribution openings are fluidly connected to the gas delivery openings;
- an intake structured to fluidly connect to a cylinder in an engine, and forming a flow path for intake gases extending between an air inlet and an intake port for feeding the intake gases into the cylinder, the mixer housing supported in the intake conduit and extending across the flow path.
3 more elements
An engine system comprising:
- an intake conduit structured to fluidly connect to a cylinder in an engine, and forming a flow path for intake gases extending between an air inlet, and an intake port for feeding the intake gases into the cylinder;
- a gaseous fuel mixer assembly including a mixer housing supported in the intake conduit and extending across the flow path, the mixer housing forming a central bore and gas delivery openings opening to the flow path and fluidly connected to the central bore;
- the mixer housing defining a longitudinal axis, and the gas delivery openings having a circumferential distribution and an axial distribution in the mixer housing;
- the gaseous fuel mixer assembly further including a spool valve within the central bore, the spool valve forming a gas supply passage and gas distribution openings fluidly connected to the gas supply passage;
- and the gaseous fuel mixer assembly further including a spool valve electrical actuator coupled with the spool valve to move the spool valve in axial directions between an open position where the gas distribution openings are fluidly connected to the gas delivery openings, and a closed position where the spool valve blocks the gas distribution openings from the gas delivery openings;
- sealing lands extending circumferentially around the longitudinal axis of the mixer housing;
- the sealing lands are in an alternating arrangement with the gas distribution openings, relative to the longitudinal axis, and have an axial distribution matched to the axial distribution of the as inlet locations, such that at the closed position the sealing lands block the gas distribution openings from the gas delivery openings, and at the open position the gas distribution openings are fluidly connected to the gas delivery openings.
4 more elements
A method of operating an engine system comprising:
- conveying intake air through a flow path in an intake conduit to an intake port fluidly connected to a cylinder in an engine;
- energizing a spool valve electrical actuator coupled with a spool valve in a gaseous fuel mixer assembly extending across the flow path in the intake conduit;
- moving the spool valve from a closed position to an open position in a mixer housing of the gaseous fuel mixer assembly, such that a gas supply passage in the spool valve is fluidly connected to gas delivery openings in the mixer housing having a circumferential distribution and an axial distribution relative to a longitudinal axis of the mixer housing, sealing lands extending circumferentially around the longitudinal axis of the mixer housing;
- the sealing lands are in an alternating arrangement with the gas distribution openings, relative to the longitudinal axis, and have an axial distribution matched to the axial distribution of the gas inlet locations, such that at the closed position the sealing lands block the gas distribution openings from the gas delivery openings, and at the open position the gas distribution openings are fluidly connected to the gas delivery openings;
- and mixing gaseous fuel delivered into the intake conduit by the moving of the spool valve with the intake air to form a combustion charge for combusting in the cylinder in the engine.
2 more elements
Dependencies are inferred from the claim text.