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:
Aug. 14, 2012
Filed:
May. 18, 2009
Akio Kumagai, Susono, JP;
Takashi Hotta, Susono, JP;
Akio Kumagai, Susono, JP;
Takashi Hotta, Susono, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi-ken, JP;
Abstract
An object of the present invention is to estimate a viscosity of a fuel with high accuracy at all times, irrespective, for example, of fuel properties or conditions of deterioration with time. An internal combustion engineincludes a fuel pumpfor supplying an injection valve with fuel in a tank. An ECUdetects a transition time t that begins when a drive signal is outputted to the fuel pumpand ends when the pump enters a steady operating state. At a start of the fuel pump, the higher the viscosity of the fuel, the longer the transition time t tends to be. The ECUtherefore detects the viscosity of the fuel based on a deviation Δt between the transition time t and a reference time t. If, for example, a biofuel is used, therefore, the latest viscosity can be accurately detected at all times even with the viscosity of the fuel fluctuating depending on, for example, properties or a condition of deterioration with time of the fuel, and the detection result can be incorporated in, for example, correction of a fuel injection pressure.