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:
Aug. 14, 2001
Filed:
Mar. 07, 1994
Michael R. Emken, Austin, TX (US);
Medtronic, Inc., Minneapolis, MN (US);
Abstract
Deposition of a pyrocarbon coating of precise thickness onto one or more substrates being levitated along with a bed of particles in a fluidized bed coating enclosure is accomplished by varying the amount of hydrocarbon supplied to the bed as a part of an upward levitating flow to compensate for changes which are detected in the size of the fluidized bed. Increases and decreases in the size of the bed are detected by monitoring either the differential pressure above and below the bed or the weight of the bed, and compensating changes are made to return the bed to its desired size by changing the flow rate of hydrocarbon. For example, when a growth in bed size is detected that is not attributable to an aberration in either particle supply or withdrawal, the amount of hydrocarbon being supplied to the bed is decreased so as to cause the size of the bed to gradually return to its desired value.