Legal status (The legal status 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 status listed.)
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 filedfiledCritical
Application grantedgrantedCritical
Publication of FR716127ApublicationCriticalpatent/FR716127A/en
H01K9/00—Lamps having two or more incandescent bodies separately heated
H01K9/02—Lamps having two or more incandescent bodies separately heated to provide substitution in the event of failure of one of the bodies
H01K9/04—Lamps having two or more incandescent bodies separately heated to provide substitution in the event of failure of one of the bodies with built-in manually operated switch
FR716127D1930-09-031930-09-03
Improvements to two-filament incandescent electric lamps
ExpiredFR716127A
(en)