Hybrid electric vehicle auxiliary oil pump
AssigneeFord Motor Company
InventorsAndrew John Silveri, Marvin Paul Kraska, Walter Joseph Ortmann
Life of this patent
Estimating the term…
Abstract
An automatic transmission for a hybrid electric vehicle where an engine is shut down during vehicle stops to improve fuel economy. The automatic transmission includes a main pump that is driven off of a transmission input shaft, and an electronically driven auxiliary pump. A shut down shuttle valve switches a hydraulic circuit connection from the main pump to the auxiliary pump for a low-reverse clutch and a forward clutch when the vehicle stops in drive or low gear. A pressure transducer, controller and steady state relay allow for closed loop feedback to control the auxiliary pump in order to assure sufficient hydraulic pressure while minimizing power consumption.
Claims9
A transmission for a hybrid electric vehicle comprising:
- an input shaft with a main transmission fluid pump drivingly connected thereto;
- an electronically controlled hydraulic shift system;
- a low-reverse clutch and a forward clutch connected to the hydraulic shift system;
- an electronically driven fluid pump having a fluid output;
- and
- a pressure transducer operatively engaging the fluid output;
- a controller in communication with the pressure transducer, and a solid state relay electronically connected to and drivable by the controller, and with the electronically driven pump electronically connected to and drivable by the solid state relay;
- a shut down shuttle valve operatively engaging the electrically driven fluid pump, the low/reverse clutch and the forward clutch and switchable to selectively engage and disengage the electronically driven pump from the hydraulic shift system.
A hybrid powertrain for a vehicle comprising:
- an internal combustion engine;
- a traction motor drivingly connected to the engine;
- and
- a transmission having an input shaft, with a main transmission fluid pump drivingly connected thereto, an electronically controlled hydraulic shift system, a low-reverse clutch and a forward clutch connected to the hydraulic shift system, an electronically driven fluid pump having a fluid output, a pressure transducer operatively engaging the fluid output, a controller in communication with the pressure transducer, a solid state relay electronically connected to and drivable by the controller, with the electronically driven pump electronically connected to and drivable by the solid state relay, and with a shut down shuttle valve operatively engaging the electrically driven fluid pump, the low/reverse clutch and the forward clutch and switchable to selectively engage and disengage the electronically driven pump from the hydraulic shift system.
Dependencies are inferred from the claim text.