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:
Nov. 04, 1980
Filed:
Feb. 21, 1979
Michael Slavin, Troy, MI (US);
Juhan Telmet, Fraser, MI (US);
Lectron Products, Inc., Troy, MI (US);
Abstract
A tone generator for producing an audible sound for a predetermined time period in response to the occurrence of one or more predetermined conditions. The tone generator comprises a diaphragm mounted within a resonant sound cavity that is activated by an electromagnetic assembly which is in turn driven by the output signal from an oscillator circuit. The control logic and timing circuit for the tone generator includes a unique PTC subassembly that provides a timed logic signal for controlling the activations of the diaphragm, as well as an independently generated signal for contemporaneously activating a lamp which provides a visual indication of the detected predetermined condition. The control logic and timing circuit is adapted to produce the proper timed logic signal despite the absence of a lamp in the circuit or a lamp failure.