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:
Jan. 27, 1981
Filed:
Jan. 22, 1976
Applicant:
Inventors:
Arun P Sahasrabudhe, Monroeville, PA (US);
Thomas C Matty, North Huntingdon Township, Irwin County, PA (US);
Assignee:
Westinghouse Electric Corp., Pittsburgh, PA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03K / ; B61L / ;
U.S. Cl.
CPC ...
307350 ; 246 / ; 250551 ; 307311 ; 307363 ;
Abstract
A more failsafe signal voltage threshold determining apparatus is disclosed for operation in a train vehicle control system, and which utilizes the forward voltage drop characteristic of an input light emitting diode of an optical isolator device as a train vehicle control signal threshold reference. The detector transistor of the optical isolator device provides an output control signal in response to an input train vehicle control signal applied to the light emitting diode which has a voltage level high enough to overcome the light emitting diode voltage drop.