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. 23, 1999
Filed:
Apr. 24, 1997
Igor Krasnov, Houston, TX (US);
Other;
Abstract
A compressed natural gas (CNG) vehicle refueling system has a hydraulic fluid reservoir, an accumulator, and two banks of cylinders, each of which has an axially moveable piston, a pair of inlets and an outlet. The pistons separate the CNG from hydraulic fluid. The refueling system drains the banks one at a time by refueling CNG vehicles with a plurality of refueling depots. Hydraulic fluid is pumped from reservoir to the cylinders to maintain 3600 psi of pressure in the cylinders while CNG is being dispensed. A pressure limiting valve limits pressure in the vessel tanks to 3000 psi. When the bank is drained of CNG, the pistons stop moving, the pressure at the outlets drops below 3000 psi, and the pressure at the inlets increases. This difference in pressure is sensed, causing the control panel to change banks. The pressure in the accumulator and the lack of pressure in the reservoir causes the hydraulic fluid to return to the reservoir. The second bank simultaneously begins to dispense CNG in the same manner as the first bank.