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:
Jun. 15, 1993
Filed:
Feb. 25, 1992
Anthony G Ehrlich, Pittsburgh, PA (US);
Union Switch & Signal Inc., Pittsburgh, PA (US);
Abstract
The invention provides a single-element coded alternating current railway track circuit which may be adapted to a double-element Phase-Selective configuration. A transmitter, via a transmitter transformer, provides a coded track signal to the track. A receiver transformer having one primary winding and a pair of secondary windings receives the track signal. One of the secondary windings is connected directly across a rectifier.The other secondary winding is connected in series with a secondary winding of a local transformer. This serial combination is electrically connected across another rectifier. A DC code-following relay is electrically connected across a rectified output of the first rectifier via two output terminals. A third output terminal allows substitution of a magnetic stick relay for the code-following relay if a double-element configuration is desired. The primary winding of the local transformer has terminals for connecting an AC source when using the optional double-element configuration.