On board hot bearing detector system with fault detection

• US 5,446,451 A
• Filed: 06/08/1993
• Issued: 08/29/1995
• Est. Priority Date: 06/08/1993
• Status: Expired due to Term

• Current Assignee: Business Alliance Capital Corp. (Banco Santander SA)
• Original Assignee: Servo Corporation of America
• Inventors: Grosskopf, George Jr.
• Primary Examiner(s): Peng, John K.
• Assistant Examiner(s): Lee, Benjamin C.
• Application Number:
  US08/073,944
• Time in Patent Office: 812 Days
• Field of Search: 340/682, 340/514, 340/515, 340/516, 340/584, 246/169 A, 246/5
• US Class Current: 340/682
• CPC Class Codes: B61K 9/06 by detecting or indicating heat radiation from overheated axles

Abstract

An on-board hot bearing detector system includes a microprocessor and heat sensors mounted on the train cars for sensing the bearing temperatures. Diagnostic circuitry is also provided to monitor the sensors and detect if a sensor is open or short. Additionally, the train line is controlled by the microprocessor and is provided with a current limiting device for protection against large currents in case of a short.

Claims

1. An on-board train monitoring system for monitoring wheel bearings distributed throughout a train, said system comprising:

a plurality of temperature sensors for sensing a temperature of said bearings;

a microprocessor coupled to said sensors for determining a status of said bearings from said temperature; and

a train line circuit activated by said microprocessor if said temperature is excessive, said train line circuit including a power source, a train line, a resistive component feeding current from said power source to said train line, and a component monitoring means for monitoring said current, said resistive component including a resistor having a positive temperature coefficient and a temperature dependent on said current to regulate said current for protecting said train line circuit, and said component monitoring means generating an alarm signal if said current is excessive, said alarm signal being fed to said microprocessor;

wherein said microprocessor cyclically activates and deactivates said line circuit in response to said alarm signal.

2. An on-board detector system for monitoring the temperatures of train bearings comprising:

a power source;

a plurality of sensors mounted on said train arranged and constructed to generate sensor signals indicative of said bearing temperatures;

a microprocessor for identifying bearings having excessive temperatures;

interfacing means for feeding said sensor signals to said microprocessor; and

diagnostic circuitry in communication with said microprocessor for monitoring a status of said sensors;

said diagnostic circuitry including a plurality of sensor resistors, each sensor resistor being coupled between one of said sensors and a voltage bus and a switch for connecting said power source to said voltage bus, said switch being selectively activated by said microprocessor;

a train line circuit including a relay selectively activated by said microprocessor and a train line controlled by said relay, said train line circuit further including a current limiting element for controlling a current level through said train line, said current limiting element including a current limiting resistor having a positive temperature coefficient;

a current monitoring means for monitoring said current level;

wherein said current monitoring means is coupled to said microprocessor, said microprocessor cyclically activating and deactivating said relay when said current level is excessive.