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. 09, 1990
Filed:
May. 06, 1988
John M Fay, Warminster, PA (US);
Hull Corporation, Hatboro, PA (US);
Abstract
The shelf-operating piston rod of an hydraulic cylinder of a freeze dryer is prevented from possibly contaminiating the freeze dryer chamber either by isolating the piston rod from the chamber by enclosing the piston rod within the chamber with an impervious flexible sleeve capable of extending and retracting with the piston rod. The pressure within the sleeve may be adjusted to approach or match the pressure within the freeze dryer chamber. Prevention of contamination alternatively may be achieved by interposing a sterilizing container between the external hydraulic cylinder and the freeze dryer and surrounding the piston rod, and subjecting the piston rod within the sterilizing container to sterilizing fluid before the piston rod is extended into the freeze dryer chamber. In one embodiment the sterilizing container is substantially the same length as the length of piston rod required to enter the freeze dryer chamber, whereby said length of piston rod may be fully retracted from the freezer dryer chamber and its full length sterilized in the sterilizing container. In a second embodiment the sterilizing container is substantially shorter than the length of piston rod required to be extended into the freeze dryer chamber, and the piston rod is sterilized progressively in the sterilizing container as it moves therethrough into the freeze dryer chamber.