The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 21, 1997
Filed:
Mar. 27, 1996
Susumu Shinohara, Toyota, JP;
Katsuhiko Teraoka, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi, JP;
Abstract
The fault diagnostic apparatus of the present invention detects a failure (a leak) of a fuel tank of an engine. In this invention, space above the fuel level in the fuel tank is connected to a canister. The canister contains an adsorbent to adsorb evaporated fuel in the tank to prevent the evaporated fuel from being released to the atmosphere. Valves are provided to the canister to keep the internal pressure of the canister within a predetermined range. A control circuit of the engine employs a pressure sensor to monitor the internal pressure of the fuel tank, and determines whether the fuel tank has failed in accordance with a change in the internal pressure of the fuel tank. Since the change in the fuel level in the fuel tank varies in accordance with the fuel consumption rate, the change in the pressure in the fuel tank also varies in accordance with the fuel consumption rate. Therefore, the control circuit stops the determining operation when the fuel consumption rate of the engine is too large or too small, to avoid an error in the diagnosis of the fuel tank.