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:
May. 05, 2009
Filed:
Apr. 12, 2007
Applicants:
Motoyuki Miyata, Hitachinaka, JP;
Noboru Tokuyasu, Hitachinaka, JP;
Katsuaki Fukatsu, Naka, JP;
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01F 1/68 (2006.01);
U.S. Cl.
CPC ...
Abstract
The objects of the present invention are to provide a high-accuracy EGR sensor, and EGR system which adopts the above sensor to measure EGR rate. The gas flow meter comprises a sensor section for measuring fluid flow rate and controller for controlling signals transmitted into and out of the sensor section, and is controlled at a working temperature of 350 to 700° C., wherein a protective coat formed on the sensor section has resistance to temperature at which deposition of a PM component in exhaust gases can be prevented.