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:
Mar. 10, 1998
Filed:
Jul. 30, 1996
Tokuhisa Nomura, Toyota, JP;
Hironori Miyakoshi, Seto, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
A fuel vapor treating apparatus that collects fuel vapor produced in a fuel tank and treats the vapor without releasing it into the atmosphere. The treating apparatus is provided with a canister that collects the fuel vapor through a vapor line. A vapor control valve provided in the canister adjusts the flow of fuel vapor directed toward the canister from the tank. A purge line connects the canister to an air intake passage of an engine. The fuel collected in the canister is purged into the air intake passage through the purge line. A purge control valve provided in the purge line adjusts the flow rate of the fuel flowing through the purge line. A three-way valve selectively switches the section to which the pressure sensor is connected between the tank side and the canister side. An electronic control unit (ECU) controls the second control valve and the three-way valve. The ECU tests the sealing of the tank side and the canister side based on the tank pressure and the canister pressure, which are detected by the pressure sensor. The ECU controls the three-way valve to alternately connect the pressure sensor to the tank side and the canister side during a predetermined time period subsequent to the starting of the engine. As the connection is switched, alteration in the output occurs in accordance with the normal state or abnormal state of the connected side. The ECU further tests the pressure sensor by distinguishing the output alteration.