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:
Aug. 29, 1989
Filed:
Feb. 07, 1989
Angel P Bezos, Montgomery County, MD (US);
Emilio A Fernandez, Fairfax County, VA (US);
Pulse Electronics, Inc., Rockville, MD (US);
Abstract
An improved timer circuit for engineman monitoring devices allows a 'drag operation' without frequent operation of the audio/visual alarms of the monitoring devices. The circuit receives an input from an existing switch in the locomotive to select the drag input state, but this input state does not necessarily select a longer time period for the reset window. More particularly, if drag is off and the speed is between approximately 1/3 and 31/2 mph, the timeout period is long (e.g., 123 seconds), but if drag is on for this speed, the timeout period is doubled (e.g., 246 seconds). Over 31/2 mph, the state of the drag switch is ignored, and the timeout period is long until a predetermined speed is reached and thereafter decreases with increasing speed. In addition, at 'zero' speed, i.e., below 1/3 mph, the timeout period is reduced to 20 seconds to prevent defeat of the system by tampering with the axle drive wires.