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:
Apr. 16, 2002
Filed:
Apr. 30, 1999
Yutaka Yamagishi, Miyanohigashi-machi, JP;
Tetsuji Asami, Miyanohigashi-machi, JP;
Shigeru Okuda, Miyanohigashi-machi, JP;
Horiba, Ltd., Kyoto, JP;
Abstract
A sampling apparatus for exhaust gas is capable of calibrating two flowmeters each other easily and precisely. A diluting air supply passage for diluting the sampled exhaust gas is connected to an upstream side of a diluting tunnel. A first flowmeter for measuring flow rate of air is provided in the diluting air supply passage. A measuring passage having a filter for capturing particulate matter in the exhaust gas diluted with the diluting air and a second flowmeter for measuring the flow rate of the diluted exhaust gas flowing this filter are connected to a downstream side of the diluting channel. Both flowmeters have high precision. A passage changeover part is provided at the downstream side of the first flowmeter of the diluting air supply passage; a passage changeover part is provided at the upstream side of the second flowmeter in the measuring passage; and a bypass passage is provided between the two passage changeover parts. After calibrating one flowmeter by using a bypass passage, the other flowmeter is calibrated by using the calibrated flowmeter.