Fuel level inference from canister temperatures

Patent metadata

Field	Value
Publication number	US-9448098-B2
Application number	US-201313910793-A
Country	US
Kind code	B2
Filing date	Jun 5, 2013
Priority date	Jun 5, 2013
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

Methods and systems for inferring a fuel level in a fuel tank based on temperature changes in a carbon canister are disclosed. In one example approach a method comprises, indicating a fuel level in a fuel tank based on a temperature change of adsorbent in a carbon canister during refueling.

First claim

The invention claimed is:

1. A method for an engine with an evaporative emission control system, comprising:
indicating an amount of fuel added to a fuel tank during a refueling event based on a time duration of a temperature change of adsorbent in a carbon canister during the refueling event, wherein the temperature change is based on a plurality of temperature sensors coupled to the carbon canister at various depths.

2. The method of claim 1 , further comprising, in response to the indicated amount of fuel added to the fuel tank during the refueling event being substantially equal to a maximum fuel level of the fuel tank, indicating a fuel level in the fuel tank based on a difference between the amount of fuel added to the fuel tank and an amount of fuel delivered to fuel injectors.

3. The method of claim 1 , wherein the time duration of the temperature change is from an initial temperature increase in the canister until an inflection point in temperature in the canister.

4. The method of claim 1 , wherein the time duration is from an initial rise in temperature at a first temperature sensor in the canister to an inflection point in temperature at a second temperature sensor in the canister downstream of the first temperature sensor.

5. The method of claim 4 , wherein the second temperature sensor is a most downstream temperature sensor in the canister to respond by more than a predetermined amount.

6. A method for an engine with an evaporative emission control system, comprising:
indicating an amount of fuel added to a fuel tank during refueling based on a time duration of a temperature change during refueling from an initial temperature change in a carbon canister until an inflection point in temperature in the canister; and
indicating an instantaneous fuel level based on a difference between the amount of fuel added to the fuel tank and an amount of fuel delivered to fuel injectors.

7. The method of claim 6 , wherein the temperature change is measured via a single temperature sensor coupled to the canister and wherein the time duration is from an initial temperature decrease in the canister during refueling until the inflection point where the temperature in the canister switches from decreasing to increasing.

8. The method of claim 6 , wherein the temperature change is based on a plurality of temperature sensors coupled to the carbon canister at various depths and wherein the time duration is from an initial rise in temperature at a first temperature sensor in the canister to an inflection point in temperature at a second temperature sensor in the canister downstream of the first temperature sensor, wherein the second temperature sensor is a most downstream temperature sensor in the canister to respond by more than a predetermined amount.

9. A method for an engine with an evaporative emission control system, comprising:
indicating an amount of fuel added to a fuel tank during a refueling event based on a time duration of a temperature change of adsorbent in a carbon canister during the refueling event, wherein the time duration of the temperature change is from an initial temperature increase in the canister until an inflection point in temperature in the canister.

10. A method for an engine with an evaporative emission control system, comprising:
indicating an amount of fuel added to a fuel tank during a refueling event based on a time duration of a temperature change of adsorbent in a carbon canister during the refueling event, wherein the time duration is a cool down duration based on a single temperature sensor coupled to the canister.

11. The method of claim 10 , wherein the cool down duration is a time duration from an initial temperature decrease in the canister during refueling until an inflection point where a temperature in the canister switches from decreasing to increasing.

Assignees

• Ford Global Tech Llc

Inventors

• Dudar Aed M
• Bunge Mark Daniel
• Yang Dennis Seung-Man

Classifications

• G07C5/00

  Registering or indicating the working of vehicles · CPC title

• B60K2015/03203

  during refuelling · CPC title

• B60K2015/03514

  with vapor recovery means · CPC title

• B60K2015/0321

  characterised by special sensors, the mounting thereof · CPC title

• F02M25/0872

  Details of the fuel vapour pipes or conduits · CPC title