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:
Nov. 25, 1997
Filed:
Mar. 07, 1996
Ernesto Renzi, Youngstown, NY (US);
The BOC Group, Inc., New Providence, NJ (US);
Abstract
The present invention provides a shelf for a freeze dryer which includes a pair of first and second flat plates spaced apart from one another, and a plurality of ribs located between the first and second plates and spaced from one another so as to define flow channels for circulating a diathermic fluid. The ribs are preferably formed of hollow tubes that are brazed to the first and second plates and the hollow tubes and plates are stress relieved so that the first plate presents a flat surface at which heat is transferred from articles to be freeze dried and the diathermic fluid. A freeze dryer shelf constructed in such manner has less thermal mass than prior art design which have solid ribs and plates welded to the ribs with a thickness sufficient to prevent the formation of surface deformations that would interrupt the flat surface of the first plate. Additionally, the freeze dryer shelf of the present invention can have a diathermic fluid section on which the articles are supported and a refrigerant section in good thermal contact therewith. A diathermic fluid circulated through the diathermic fluid section cools the articles to the freezing point of water while the diathermic fluid is cooled by a refrigerant circulating through the refrigerant section. Such heat exchange provided for in the freeze dryer shelf helps eliminate heat leeks that are involved in prior art freeze driers using external heat exchangers.