Device for diagnosing malfunction in a fuel tank

• US 5,925,817 A
• Filed: 12/24/1997
• Issued: 07/20/1999
• Est. Priority Date: 12/26/1996
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kidokoro, Toru, Ito, Takaaki, Hyodo, Yoshihiko
• Primary Examiner(s): RAEVIS, ROBERT R
• Application Number:
  US08/998,273
• Time in Patent Office: 573 Days
• Field of Search: 73/118.1, 73/40, 73/49.2, 73/49.3, 73/40.7, 701/31
• US Class Current: 73/40
• CPC Class Codes: B60K 15/03 Fuel tanks chassis frame comprising fluid storage compartment B62D21/16 ; Details of the fuel feeding system related to the fuel tank F02M37/0076
• CPC Class Codes: B60K 15/03504 adapted to avoid loss of fuel or fuel vapour, e.g. with vapour recovery systems
• CPC Class Codes: B60K 2015/03223 comprising at least two level fuel sensors
• CPC Class Codes: F02D 33/003 Controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus control of electrical fuel pumps F02D41/3082, controlling fuel flow to a common rail F02D41/3845; Failure or leakage prevention; Diagnosis or detection of failure; Arrangement of sensors in the fuel system; Electric wiring; Electrostatic discharge
• CPC Class Codes: F02M 25/089 Layout of the fuel vapour installation
• CPC Class Codes: F02M 37/0082 Devices inside the fuel tank other than fuel pumps or filters electrical pumps submerged in fuel tanks F02M37/10, jet pumps F02M37/025
• CPC Class Codes: F02M 37/10 submerged in fuel, e.g. in reservoir
• CPC Class Codes: F02M 37/20 characterised by means for preventing vapour lock

Abstract

According to the present invention, there is provided a device for diagnosing malfunction in a fuel tank. The fuel tank has a separator wall therein which separates an interior of the fuel tank into a fuel chamber and an air chamber. The separator wall is deformable according to an amount of fuel in the fuel chamber. The device comprises a device for detecting a change of at least one of a position of the separator wall, the pressure in the tank and the concentration of fuel vapor in the tank, and a device for diagnosing malfunction of the separator wall on the basis of the change to diagnose that the separator wall has malfunction when the change differs from a predetermined regular change.

Claims

1. A device for diagnosing malfunction in a fuel tank, said fuel tank having a separator wall therein which separates an interior of said tank into a fuel chamber and an air chamber said wall being deformable according to an amount of fuel in said fuel chamber, said device comprising:

means for detecting a change of a concentration of fuel vapor in said fuel tank, and

means for diagnosing malfunction of said separator wall on the basis of said change to diagnose that said separator wall has malfunction when said change differs from a predetermined regular change.

2. A device for diagnosing malfunction in a fuel tank according to claim 1, wherein said malfunction diagnosing means diagnoses that said separator wall has malfunction on the basis of difference in the concentration of fuel vapor before and after a refueling operation to supply said fuel chamber with fuel.

3. A device for diagnosing malfunction in a fuel tank according to claim 1, wherein said fuel tank is in communication with an engine, and said malfunction diagnosing means diagnoses that said separator wall has malfunction on the basis of difference in the concentration of fuel vapor before and after a purge operation to purge fuel vapor to said engine.

4. A device for diagnosing malfunction in a fuel tank according to claim 1, wherein said malfunction diagnosing means diagnoses that said separator wall has malfunction when a concentration of fuel vapor is higher than a predetermined concentration.

5. A device for diagnosing malfunction in a fuel tank according to claim 4, wherein said fuel tank is in communication with an engine, and said malfunction diagnosing means diagnoses that said separator wall has malfunction when a concentration of fuel vapor is higher than the predetermined concentration during a purging operation to purge fuel vapor to said engine.

6. A device for diagnosing malfunction in a fuel tank according to claim 4, wherein said malfunction diagnosing means diagnoses that said separator wall has malfunction when a concentration of fuel vapor is higher than the predetermined concentration during a refueling operation to supply said fuel chamber with fuel.

7. A device for diagnosing malfunction in a fuel tank according to claim 1, wherein said malfunction diagnosing means diagnoses that said separator wall has malfunction on the basis of amount of fuel in said air chamber.

8. A device for diagnosing malfunction in a fuel tank according to claim 1, wherein prohibiting means is provided for prohibiting the diagnosis of said malfunction diagnosis means on the basis of at least one of an engine driving time, a temperature surrounding said fuel tank, an atmosphere pressure, and a fuel temperature in said fuel tank.

9. A device for diagnosing malfunction in a fuel tank according to claim 1, wherein an indicator is provided for indicating malfunction of said separator wall to indicate malfunction of said separator wall when said malfunction diagnosis means diagnoses that the separator wall has malfunction.