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:
Jan. 07, 1997
Filed:
Feb. 26, 1996
Susumu Shinohara, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi, JP;
Abstract
The evaporative emission control system in the present invention is equipped with a fuel tank and a canister connected to the fuel tank, and a pressure sensor connected to the canister and the fuel tank via a three-way switching valve. The pressure sensor can be selectively connected to the canister and the fuel tank by switching the position of the three-way switching valve. The control circuit, which may consist of a known type of microcomputer, detects failures in the system based on the smoothed pressure values of the canister and the fuel tank. The smoothed pressure value is obtained by smoothing fluctuations of the pressure detected by the pressure sensor. Since the characteristics of the fluctuations of the pressure in the canister and the fluctuations of the pressure in the fuel tank are different, the control circuit changes the degree of smoothing fluctuation when obtaining the smoothed pressure value of the canister and when obtaining the smoothed pressure value of the fuel tank.