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. 07, 1989
Filed:
Jan. 12, 1987
Applicant:
Inventors:
James R Hoelscher, Rochester, NY (US);
Klaus H Frielinghaus, Rochester, NY (US);
Frank A Raso, Spencerport, NY (US);
Barry L Smith, Rochester, NY (US);
Assignee:
General Signal Corporation, Stamford, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B61L / ;
U.S. Cl.
CPC ...
246 / ; 246 / ; 2461 / ; 2464 / ;
Abstract
An audio frequency (AF) track circuit whereby a railway track tuned loop transmitter operating in a dual resonant mode, for handling, two signal frequencies, can be coupled to the rails. Each frequency is conducted through a tuning unit having series and parallel branches tuned to each frequency. The track circuit using the tuned loop transmitter eliminates DC return current imbalance effects while maintaining suitably high track circuit shunting sensitivity.