Passive venturi pump for leak diagnostics and refueling
First Claim
Patent Images
1. A method for operating a vehicle with an engine, comprising:
- during vehicle motion, passing air through a venturi coupled to the vehicle to generate vacuum;
selectively storing the generated vacuum in an accumulator by controlling a valve arranged in a conduit coupling the venturi with the accumulator based on vehicle speed and an amount of accumulator vacuum; and
in response to a condition, discharging the stored vacuum to a vacuum consuming system of the vehicle.
1 Assignment
0 Petitions
Accused Products
Abstract
Systems and methods for operating a hybrid electric vehicle with a passive venturi pump are disclosed. In one example approach, a method comprises: during vehicle motion, passing air through a venturi coupled to the vehicle to generate vacuum; storing the generated in an accumulator; and, in response to a condition, discharging the stored vacuum to a vacuum consuming system of the vehicle.
-
Citations
18 Claims
-
1. A method for operating a vehicle with an engine, comprising:
-
during vehicle motion, passing air through a venturi coupled to the vehicle to generate vacuum; selectively storing the generated vacuum in an accumulator by controlling a valve arranged in a conduit coupling the venturi with the accumulator based on vehicle speed and an amount of accumulator vacuum; and in response to a condition, discharging the stored vacuum to a vacuum consuming system of the vehicle. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A method of operating an engine emission control system in a hybrid vehicle, comprising:
-
during vehicle motion, passing ram air through a venturi coupled to the vehicle to generate vacuum; selectively storing the generated vacuum in an accumulator until an engine-off condition, monitoring an amount of vacuum in the accumulator with a pressure sensor arranged in the accumulator, and increasing a threshold speed value based on an increased amount of vacuum stored in the accumulator, wherein selectively storing the generated vacuum includes controlling a valve arranged in a conduit coupling the venturi with the accumulator based on vehicle speed and an amount of accumulator vacuum, including controlling the valve to provide vacuum generated by the venturi to the accumulator for storage therein when a speed of the vehicle is greater than the threshold speed value and controlling the valve to not provide vacuum generated by the venturi to the accumulator for storage therein when the speed of the vehicle is less than the threshold speed value; and during the engine-off condition, isolating the emission control system from the atmosphere and indicating a leak in response to depletion of stored vacuum. - View Dependent Claims (13, 14, 15, 16)
-
-
17. A hybrid vehicle system, comprising:
-
an engine emission control system including a fuel vapor retaining device coupled to a fuel tank; a vacuum accumulator coupled to the engine emission control system through a first valve; a venturi coupled to an ambient air intake, where the venturi is coupled to the accumulator through a second valve; a pressure sensor disposed within the emission control system; a pressure sensor disposed in the accumulator; a vehicle speed sensor; and a computer readable storage medium having instructions encoded thereon, including; instructions to, in response to vehicle motion, open the second valve and close the first valve to charge the accumulator with vacuum generated by the venturi; instructions to close the second valve and maintain the first valve closed to store vacuum generated by the venturi in the accumulator; instructions to open the first valve to discharge vacuum stored in the accumulator to the emission control system for a duration; instructions to indicate a leak in the emission control system in response to a pressure change in the emission control system during the duration; and instructions to open the second valve and close the first valve to charge the accumulator with vacuum generated by the venturi when a speed at which the vehicle is traveling is greater than a threshold speed value and close the second valve to not charge the accumulator with vacuum generated by the venturi when the speed at which the vehicle is traveling is less than the threshold speed value, wherein the threshold speed value is based on an amount of vacuum stored in the accumulator. - View Dependent Claims (18)
-
Specification