Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US06/579,401external-prioritypatent/US4511659A/en
Application filed by Esa IncfiledCriticalEsa Inc
Application grantedgrantedCritical
Publication of ATE54754T1publicationCriticalpatent/ATE54754T1/de