Method and device for diagnosing tank leaks using a reference measuring method

• US 6,845,652 B2
• Filed: 06/24/2002
• Issued: 01/25/2005
• Est. Priority Date: 06/22/2001
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Stegmann, Volk r, Wiltsch, Peter, Fritz, Thorsten, Streib, Martin, Hassdenteufel, Armin
• Primary Examiner(s): Garber, Charles D.
• Application Number:
  US10/178,459
• Publication Number:
  US 20030015022A1
• Time in Patent Office: 946 Days
• Field of Search: 73/492, 73/497, 73/40, 73/405.R, 123/520, 702/51
• US Class Current: 73/49.2
• CPC Class Codes: F02M 25/0818 having means for pressurising the evaporative emission space
• CPC Class Codes: G01M 3/025 Details with respect to the testing of engines or engine parts
• CPC Class Codes: G01M 3/3236 by monitoring the interior space of the containers
• CPC Class Codes: G01M 3/3263 using a differential pressure detector G01M3/3245, G01M3/3272 take precedence

Abstract

In a method and a device for leak testing of a vessel, e.g., a tank venting system of a motor vehicle, a leak-tightness measurement is performed by introducing a positive pressure or partial vacuum and detecting the variation over time of a positive pressure or partial vacuum in the vessel, and a reference measurement is performed using a reference leak. A conclusion is drawn as to the presence of a leak in the vessel by comparing the results of the leak-tightness measurement and the reference measurement. To avoid faulty diagnoses, the positive pressure or partial vacuum during the leak-tightness measurement and the reference measurement is detected by using a single pressure measuring device.

Claims

1. A method for leak testing a vessel, comprising the steps of:

introducing one of a positive pressure and a partial vacuum into the vessel;

detecting a variation over time of the one of the positive pressure and the partial vacuum in order to perform a leak-tightness measurement on said vessel and a corresponding reference measurement on said vessel using a reference leak in fluid communication with the one of the positive pressure and the partial vacuum;

determining a presence of a leak in the vessel by comparing results of the leak-tightness measurement and the reference measurement;

wherein during the leak-tightness measurement and the reference measurement, the one of the positive pressure and the partial vacuum is detected using a single pressure measuring device;

and wherein the vessel and the reference leak are alternately subjected to the one of the positive pressure and the partial vacuum; and

detecting and comparing respective resulting pressure variations upstream from a pressure source to one another, from which a determination is made as to leak-tightness of the vessel.

2. The method according to claim 1, wherein:

the vessel is a tank venting system of a motor vehicle.

3. The method according to claim 1, further comprising:

determining a malfunction of the pressure source from a fluctuation over time in a pressure characteristic that occurs upstream from the pressure source.

4. The method according to claim 3, further comprising:

the pressure source being a vane-type pump; and

diagnosing at least one jammed pump vane from a pressure fluctuation.