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:
Dec. 14, 1993
Filed:
Oct. 29, 1992
Seifollah S Nanaji, Greensboro, NC (US);
Edward A Payne, Greensboro, NC (US);
Kenneth L Pope, Walkerton, NC (US);
Hal C Hartsell, Jr, Kernersville, NC (US);
Gilbarco, Inc., Greensboro, NC (US);
Abstract
An apparatus for pumping recovered vapor in a vapor recovery liquid fuel dispenser includes a liquid fuel dispenser apparatus adapted to dispense liquid fuel to a liquid fuel dispenser nozzle proximate a fuel vapor passage. A transducer associated with the dispenser apparatus generates a liquid fuel flow signal indicative of the rate of liquid fuel flow therethrough. A vapor pump driven by an electric motor is arranged to pump vapor from the vapor passage through a vapor pump inlet to a vapor pump outlet and has a characteristic that the flow rate through the vapor pump at a given vapor pump operating speed is inversely proportional to the difference between the vapor pump inlet and outlet pressures. Sensors associated with the inlet and outlet ascertain inlet and outlet pressures and generate signals representative thereof. A controller for the vapor pump includes vapor recovery control electronics and motor drive electronics. The vapor recovery electronics receive the pressure signals, a vapor pump speed signal and the liquid fuel flow signal and output a motor velocity modulation signal to the motor drive electronics to correlate the vapor pump flow rate with the liquid fuel flow rate. The motor drive electronics convert the motor velocity modulation signal to a voltage drive signal to the motor to adjust the vapor pump operating speed. Any discrepancies between the vapor pump flow rate derived from the pressure signals and the liquid fuel flow rate are thereby reduced.