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:
Dec. 17, 1985
Filed:
Mar. 28, 1983
Etienne Camus, Senlis, FR;
Abstract
A total security time-delay circuit useful in railway communications, for example, provides a series of output pulses after a specific minimum interval in response to a direct voltage applied to an input of the circuit, the minimum interval being maintained even in the event of circuit component malfunctions. A pulse generator connected to the circuit input provides a series of pulses to control a first contact breaker which switches the primary winding of a transformer to partially discharge a capacitor which is series-connected to the primary winding. The capacitor charges through a resistive network of a transformer secondary winding circuit which includes a second contact breaker having a control terminal connected to the transformer secondary winding and operable to provide output pulses when the capacitor discharge reaches a sufficient intensity. A grounded Zener diode connected to a junction of the resistive network and a switch terminal of the second contact breaker ensures that the time delay of the output pulses is not reduced below the minimum interval, even in the event of malfunctions in other circuit components.