Refueling systems and methods for mixed liquid and gaseous fuel

• US 10,370,238 B2
• Filed: 10/20/2016
• Issued: 08/06/2019
• Est. Priority Date: 10/10/2013
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Leone, Thomas G., Dearth, Mark Allen
• Primary Examiner(s): Arnett, Nicolas A
• Application Number:
  US15/299,287
• Publication Number:
  US 20170036904A1
• Time in Patent Office: 1,020 Days
• CPC Class Codes: B60K 15/03006 Gas tanks B60K15/07 takes precedence
• CPC Class Codes: B60K 2015/03019 Filling of gas tanks
• CPC Class Codes: B60K 2015/03026 comprising a valve
• CPC Class Codes: B67D 7/04 for transferring fuels, lubricants or mixed fuels and lubricants
• CPC Class Codes: B67D 7/0478 constructional features or components vapour recovery nozzles B67D7/54
• CPC Class Codes: B67D 7/78 Arrangements of storage tanks, reservoirs or pipe-lines
• CPC Class Codes: F02B 2043/103 Natural gas, e.g. methane or LNG used as a fuel
• CPC Class Codes: F02B 43/10 Engines or plants characterised by use of other specific gases, e.g. acetylene, oxyhydrogen
• CPC Class Codes: F02B 43/12 Methods of operating

Abstract

A fuel tank system, comprising: a fuel tank configured to store a liquid fuel and a pressurized gaseous fuel capable of partially dissolving in the liquid fuel; a refueling conduit coupled to the fuel tank via a tank access valve; a first high pressure refueling port coupled to the refueling conduit; a low pressure refueling port coupled to the refueling conduit via a check valve. In this way, pressurized gaseous fuel or a pre-pressurized mix of fuels may be added to the fuel tank without active control any time the fuel pressure in the fuel tank is below a maximum allowable pressure, and liquid fuel may be added to the fuel tank with active control whenever the fuel pressure and liquid fuel level in the fuel tank are below threshold levels.

Claims

1. A method for refueling a fuel tank of a vehicle, comprising:

responsive to a first condition, pumping gaseous fuel from the fuel tank into a secondary vapor tank, while storing a liquid fuel and a distinct pressurized gaseous fuel only partially dissolved in the liquid fuel in the fuel tank, wherein during the pumping the secondary vapor tank is fluidically isolated from atmosphere, and wherein the gaseous fuel comprises a first fuel type and the liquid fuel comprises a second fuel type different from the first fuel type.

2. The method of claim 1, where the first condition includes:

a detection of a liquid refueling request; and

a fuel tank pressure that is less than a first threshold, but greater than a second threshold, the second threshold less than the first threshold.

3. The method of claim 2, further comprising:

responsive to a second condition, ceasing pumping of gaseous fuel from the fuel tank into the secondary vapor tank;

fluidically isolating the secondary vapor tank from the fuel tank; and

enabling addition of liquid fuel to the fuel tank.

4. The method of claim 3, where the second condition includes a fuel tank pressure that is less than the second threshold.

5. The method of claim 3, further comprising, during both the first and the second condition, storing the liquid fuel in the fuel tank until the fuel tank pressure is higher than the first threshold or a fuel tank liquid level reaches a threshold level.

6. The method of claim 2, wherein the liquid refueling request is a direct request from an operator received via an interface or via operator opening of a refueling door.

7. The method of claim 2, wherein the liquid refueling request is an indirect request including detection of proximity of a vehicle to a refueling station by GPS or by direct communication between the vehicle and the refueling station.

8. The method of claim 2, wherein the second threshold is based on a volume of the secondary vapor tank and an amount of gaseous fuel that can be added to the secondary vapor tank.

9. The method of claim 1, wherein the pumping includes activating a fuel pump, included in a gaseous fuel line upstream of the secondary vapor tank, to pump the gaseous fuel to the secondary vapor tank, wherein during the pumping the secondary fuel vapor tank comprises only a single inlet and no outlets, wherein the single inlet comprises the gaseous fuel line.

10. The method of claim 1, wherein enabling addition of liquid fuel to the fuel tank includes opening a refueling lock and receiving the liquid fuel in the fuel tank via a low pressure refueling port of a refueling conduit.

11. A method, comprising:

storing a liquid fuel and a pressurized gaseous fuel, only partially dissolved in the liquid fuel, in a fuel tank; and

responsive to a liquid refueling request,

pumping gaseous fuel from the fuel tank into a secondary tank via a pump positioned upstream from the secondary tank before enabling addition of liquid fuel into the fuel tank when the fuel tank pressure is above a threshold, the threshold based on a volume of the secondary tank, and wherein during the pumping the secondary tank is fluidically isolated from atmosphere, and wherein the gaseous fuel comprises a first fuel type and the liquid fuel comprises a second fuel type chemically distinct from the first fuel type.

12. The method of claim 11, further comprising:

enabling addition of liquid fuel into the fuel tank without prior pumping of the gaseous fuel from the fuel tank into the secondary tank when fuel tank pressure is below the threshold.

13. The method of claim 11, further comprising ceasing the pumping of gaseous fuel when the fuel tank pressure is below the threshold.

14. The method of claim 11, wherein the liquid fuel is received in the fuel tank via a low pressure refueling port of a refueling conduit, the low pressure refueling port distinct from a high pressure refueling port of the refueling conduit for receiving both pressurized gaseous fuel and a pre-pressurized mixture of the liquid fuel and gaseous fuel.

15. The method of claim 14, wherein enabling addition of the liquid fuel includes opening a refueling lock of the low pressure refueling port.

16. The method of claim 11, wherein the pump is coupled in a gaseous fuel line between the fuel tank and the secondary tank.

17. The method of claim 11, wherein the threshold is further based on an amount of gaseous fuel that can be added to the secondary tank.