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. 06, 1991
Filed:
Sep. 22, 1988
Masuo Akamatsu, Katsuta, JP;
Hiroatsu Tokuda, Katsuta, JP;
Izumi Watanabe, Katsuta, JP;
Hiroshi Yoneda, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Automotive Engineering Co., Ltd., Ibaraki, JP;
Abstract
A hot wire type air flow meter employing a hot wire temperature dependent resistor having a heat generating portion and a non-heat generating portion comprising a feedback control circuit controlling the hot wire temperature dependent resistor temperature constant which includes a phase shift circuit for inducing a sufficient phase delay in feedback signals thereby compensating a second stage delay in output signals of the air flow meter caused by the thermal inertia of the non-heat generating portion and enhancing response characteristic of the air flow meter.