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:
Oct. 26, 1999
Filed:
Sep. 25, 1997
Robert S Smith, Houston, TX (US);
Igor Krasnov, Houston, TX (US);
Other;
Abstract
A compressed natural gas (CNG) vehicle refueling system is designed for refueling fleets of vehicles with identical fuel tanks. The amount of CNG dispensed into the tanks may be closely approximated without the use of a flow meter. An initial standardized volume is calculated based upon the ambient temperature, the initial pressure level and an approximate compressibility of the gas. Gas is dispensed into the fuel tank to a desired pressure which is confirmed with a pressure gage. A final standardized volume of gas contained within the fuel tank is calculated based upon the final pressure level and assuming no change in the compressibility of the gas. The initial standardized volume of gas is subtracted from the final standardized volume of gas to yield an actual volume of gas dispensed from the storage vessel. Empirically derived temperature correction factors may be used to generate an even more accurate approximation of CNG dispensed. The temperature correction factors compensate for the difference in temperature between operating temperatures and the standardized temperature of zero degrees celsius.