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:
Feb. 10, 1981
Filed:
Apr. 13, 1979
Karlheinz Schreyer, Wolfratshausen, DE;
Karla Oberstein, Neuried, DE;
Siemens Aktiengesellschaft, Berlin & Munich, DE;
Abstract
A danger alarm system has a plurality of call lines and a plurality of alarm circuits respectively connectible to the call lines and operable to provide signals indicative of environmental conditions about the alarm circuits. A central exchange is connected to the call lines and includes a write-read memory and means connected thereto for inputting the busy condition of each of the lines. A multiplexer is connected between the lines and the memory for sequentially interrogating the memory and the lines. Evaluation circuits are provided and operated upon comparison of the call line signals and the corresponding memory locations.