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:
Jan. 26, 1999
Filed:
May. 02, 1997
Philip A Lessard, Boxborough, MA (US);
Paul E Dresens, Arlington, MA (US);
Maureen C Buonpane, Mansfield, MA (US);
Timothy M Pulling, Franklin, MA (US);
Alan C Brightman, Bridgewater, MA (US);
Robert M Patterson, Burlington, MA (US);
Mark A Stira, Wilmington, MA (US);
Allen J Bartlett, Mendon, MA (US);
Stephen J Yamartino, Wayland, MA (US);
Gary S Ash, Walpole, MA (US);
James A O'Neil, Bedford, MA (US);
Helix Technology Corporation, Mansfield, MA (US);
Abstract
A cryopump is regenerated by roughing the cryopump during purging. Purging and roughing is carried out in first a high temperature mode and then a lower ambient temperature mode. In the lower temperature mode, the cryogenic refrigerator is turned on. If the system fails a rough test after roughing at the lower temperature, it is repurged with the rough valve open.