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.)
Publication date
Publication of BE462639ApublicationCriticalpatent/BE462639A/xx
G04C21/00—Producing acoustic time signals by electrical means
G04C21/16—Producing acoustic time signals by electrical means producing the signals at adjustable fixed times
G04C21/20—Producing acoustic time signals by electrical means producing the signals at adjustable fixed times by closing a contact to ring an electromechanical alarm
G04C21/22—Producing acoustic time signals by electrical means producing the signals at adjustable fixed times by closing a contact to ring an electromechanical alarm put into action by the arbor of a mechanical alarm work