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. 11, 1995
Filed:
Sep. 03, 1993
Keith Gustafson, Waleska, GA (US);
Minnesota Valley Engineering, Inc., New Prague, MN (US);
Abstract
The storage tank consists of a main tank and ullage tank connected by a relatively small passage having a flow rate capacity up to 30% of the main fill line. To fill the tank, liquid cryogen is delivered to the main tank by either a top or bottom fill. Because the fill line is significantly larger than the passage, the main tank will become liquid full while the ullage tank remains substantially empty. When the tank becomes liquid full a dramatic drop in the flow rate will result that can be detected by a relatively insensitive, and inexpensive, flow monitoring device thereby to stop the filling operation. The ullage tank will retain trapped gas and gradually allow the liquid from the main tank to enter the ullage tank through the passage until the liquid level in the tanks are equal. Once the liquid levels in the tanks equalize, a vapor space is created above the liquid to accommodate vaporizing cryogen and provide long hold times.