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
Application filed by Helvar OyfiledCriticalHelvar Oy
Priority to FI813297ApriorityCriticalpatent/FI64487C/fi
Priority to FI820095Aprioritypatent/FI63147C/fi
Priority to US06/420,010prioritypatent/US4492897A/en
Priority to DE19823235197prioritypatent/DE3235197A1/de
Publication of FI813297LpublicationCriticalpatent/FI813297L/fi
Application grantedgrantedCritical
Publication of FI64487BpublicationCriticalpatent/FI64487B/fi
Publication of FI64487CpublicationCriticalpatent/FI64487C/fi