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. 04, 2005
Filed:
Sep. 25, 2002
Atsushi Kanke, Hitachi, JP;
Masahiro Matsumoto, Hitachi, JP;
Shinya Igarashi, Ibaraki, JP;
Keiji Hanzawa, Mito, JP;
Kei Ueyama, Hitachinaka, JP;
Atsushi Kanke, Hitachi, JP;
Masahiro Matsumoto, Hitachi, JP;
Shinya Igarashi, Ibaraki, JP;
Keiji Hanzawa, Mito, JP;
Kei Ueyama, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Car Engineering Co., Ltd., Ibaraki, JP;
Abstract
In a thermal-type airflow meter that measures an intake airflow rate in an internal combustion engine of an automobile or the like, there has been a problem that pulsation errors caused by external fluctuations under the environment including a large pulsation and reverse flow in the intake valve are difficult to be reduced. In order to solve this problem, the invention provides a flowmeter comprising a detection element that outputs a non-linear signal corresponding to a flow rate, and a regulation means that regulates an output signal of the detection element for controlling. With this construction, the regulation means executes output regulation processing that regulates irregularities of the detection element in the output signal, and inequality linearization processing that regulates an average value of the output signal after the output regulation processing by means of regulating parameters.