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. 12, 2002
Filed:
Feb. 26, 1999
Hitoshi Ishikawa, Hitachinaka, JP;
Other;
Abstract
A thermal type air flow meter includes a device for measuring an intake air flow rate by heating and controlling a heating resistor, and an analog-to-digital converter for digitizing an air flow rate signal of the air flow rate measurement device. The air flow rate measurement device inputs a reference voltage to the analog-to-digital converter so that the reference voltage can be converted from an analog signal to a digital signal, and the air flow rate signal can be corrected in accordance with the value of the reference voltage. A/D conversion of the air flow rate signal can be executed accurately even when the voltage of the reference voltage source of the A/D converter in an electrical control unit is fluctuating.