METHOD FOR DIAGNOSING FUEL TANK LEAKS, AND APPARATUS APPLYING SAME

• US 20130297177A1
• Filed: 09/02/2011
• Published: 11/07/2013
• Est. Priority Date: 09/06/2010
• Status: Abandoned Application

• Current Assignee: Vitesco Technologies GmbH (INA-Holding Schaeffler GmbH & Co. KG)
• Original Assignee: Continental Automotive GmbH (Continental AG)
• Inventors: Kim, Han Cin, Son, Yong Joon
• Application Number:
  US13/821,151
• Publication Number:
  US 20130297177A1
• Time in Patent Office: Days
• US Class Current: 701/102
• CPC Class Codes: F02D 2041/225 Leakage detection
• CPC Class Codes: F02D 2200/0602 Fuel pressure
• CPC Class Codes: F02D 41/003 Adding fuel vapours, e.g. drawn from engine fuel reservoir
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02D 45/00 Electrical control not provided for in groups F02D41/00 - F02D43/00
• CPC Class Codes: F02M 25/0809 Judging failure of purge control system
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

An apparatus and a method for diagnosing the leak of a fuel tank are disclosed. The leak of the fuel tank is immediately diagnosed when a vehicle is stopped by controlling the pressure of the fuel tank during the driving of the vehicle. Even if negative pressure is not formed when the vehicle is stopped, or the diagnosis rate of the fuel tank has to be increased, the leak of the fuel tank is able to be easily diagnosed.

Claims

1-10. -10. (canceled)

12. A method of diagnosing a leak of a fuel tank of a vehicle, the method comprising:

determining a satisfaction of a first condition that is used to check a status of at least one basic parameter required to control a pressure of the fuel tank during a driving of the vehicle;

determining, if the first condition is satisfied, a satisfaction of a second condition that is used to determine whether a pressure control operation of the fuel tank is started;

adjusting, if the second condition is satisfied, a target pressure value of the fuel tank according to a driving condition of the vehicle; and

controlling a formation of the pressure in the fuel tank in accordance with the target pressure value, by an apparatus for diagnosing the leak of the fuel tank.

13. The method of claim 12, further comprising diagnosing the leak of the fuel tank based on the pressure of the fuel tank when the vehicle is stopped in order to diagnose the leak of the fuel tank.

14. The method of claim 12, wherein the first condition includes at least one of:

if an error occurs in at least one device to diagnose the leak of the fuel tank,

if fuel is cooled,

if an external temperature condition is satisfied when an engine is started,

if a battery voltage is effective,

if an amount of the fuel is effective, and

if the fuel is supplied.

16. The method of claim 12, wherein the step of controlling the formation of the pressure includes, if the pressure of the fuel tank is greater than the target pressure value, opening a canister purge valve so that the pressure of the fuel tank is reduced.

17. The method of claim 12, wherein the step of controlling the formation of the pressure includes, if the pressure of the fuel tank is lower than the target pressure value, opening a canister cut off valve so that the pressure of the fuel tank is increased.

18. The method of claim 12, wherein:

the step of controlling the formation of the pressure includes, if the pressure of the fuel tank is within a hysteresis based on the target pressure value, abstaining from performing an open control operation of one of a canister purge valve and a canister cut off valve, and

the step of controlling the formation of the pressure includes, if the pressure is out of the hysteresis based on the target pressure value, performing the open control operation of one of the canister purge valve and the canister cut off valve.

19. The method of claim 12, wherein the driving condition includes at least one of a vehicle speed, an amount of intake air, and an engine load.

20. The method of claim 13, wherein the diagnosing of the leak of the fuel tank includes:

holding, if the pressure of the fuel tank is not reduced to the target pressure value, the diagnosing of the leak of the fuel tank until a canister purge valve is open so that the pressure of the fuel tank reaches the target pressure value, wherein the target pressure value corresponds to when the vehicle is stopped.

21. An apparatus for diagnosing a leak of a fuel tank of a vehicle, the apparatus comprising:

a first determining part for determining a satisfaction of a first condition that is used to check a status of at least one basic parameter required to control a pressure of the fuel tank during a driving of the vehicle;

a second determining part for determining, if the first condition is satisfied, a satisfaction of a second condition that is used to determine whether a pressure control operation of the fuel tank is started;

an adjusting part for adjusting, if the second condition is satisfied, a target pressure value of the fuel tank according to a driving condition of the vehicle; and

a controller for controlling a formation of the pressure in the fuel tank in accordance with the target pressure value.

22. The apparatus of claim 21, further comprising a diagnosing part for diagnosing the leak of the fuel tank based on the pressure of the fuel tank when the vehicle is stopped.