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:
Mar. 31, 1998
Filed:
Apr. 24, 1996
Asad M Madni, Los Angeles, CA (US);
Lawrence A Wan, Malibu, CA (US);
Jim Bi Vuong, Northridge, CA (US);
BEI Sensors & Systems Company, Inc., Sylmar, CA (US);
Abstract
A fuzzy logic controller for a cryogenic system in which, for example, a cold tip cooling an infrared detector uses a Stirling cycle cooler-compressor with the helium coolant maintained at typically 78.degree. K. This temperature is maintained by a fuzzy logic controller which has as its inputs the temperature differential between the desired temperature and actual cold tip temperature, rate of change of such temperature, and especially for startup the difference between a maximum voltage which can be applied to the Stirling type cooler-compressor and the actual control voltage which is applied. Appropriate membership functions for all of the inputs are provided of the triangular type. And appropriate rules related to the operation of a Stirling cycle cooler provide for fuzzy outputs which with an output membership function are defuzzified to provide a control output signal which controls the final cooling power of the cooler-compressor.