Hot rail wheel bearing detection
A system for detecting a moving hot bearing or wheel of a rail car is provided. The system includes a first comparator to receive input signals representative of radiation emitted by the moving hot rail car bearing or wheel, and to compare the input signals to a threshold value. The system further includes a counter for counting incidents of the input signals exceeding the threshold value and a second comparator to compare a number of incidents of the input signals exceeding the threshold value to a count threshold as an indication of detection of a hot rail car bearing or wheel.
1. A system for detecting a moving hot bearing or wheel of a rail car comprising:
a first comparator configured to receive input signals representative of radiation emitted by the moving hot rail car bearing or wheel, and to compare the input signals to a threshold value;
a counter configured to count incidents of the input signals exceeding the threshold value; and
a second comparator configured to compare a number of incidents of the input signals exceeding the threshold value to a count threshold as an indication of detection of a hot rail car bearing or wheel.
2. The system of claim 1 , wherein the first comparator, the counter and the second comparator are implemented as appropriate programming in digital processing circuitry.
3. The system of claim 1 , wherein the first comparator, the counter and the second counter are implemented as analog circuits.
4. The system of claim 1 , wherein the counter is configured to count successive incidents of the input signals exceeding the threshold value.
5. The system of claim 4 , wherein the counter is configured to decrement a count when sampled input signals do not exceed the threshold value.
6. The system of claim 1 , comprising sensors disposed adjacent to a rail for detecting the radiation emitted by the moving hot rail bearing or wheel.
7. The system of claim 6 wherein, the sensor for sensing the infrared radiation comprises a pyroelectric infrared sensor.
8. The system of claim 1 , comprising communications circuitry configured to communicate an alarm signal to a remote monitor indicating that a bearing or wheel temperature is in excess of a desired value based upon the output.
9. The system of claim 1 , wherein the threshold value is set by an adaptive algorithm.
10. A system for detecting a moving hot bearing or wheel of a rail car comprising:
sensors disposed adjacent to a rail for detecting the radiation emitted by the moving hot rail bearing or wheel;
a first comparator configured to receive input signals from the sensors representative of radiation emitted by the moving hot rail car bearing or wheel, and to compare the input signals to a threshold value;
a counter configured to count incidents of the input signals exceeding the threshold value; and
a second comparator configured to compare a number of incidents of the input signals exceeding the threshold value to a count threshold as an indication of detection of a hot rail car bearing or wheel.
11. The system of claim 10 , wherein the first comparator, the counter and the second comparator are implemented as appropriate programming in digital processing circuitry.
12. The system of claim 10 , wherein the first comparator, the counter and the second counter are implemented as analog circuits.
13. The system of claim 10 , wherein the counter is configured to count successive incidents of the input signals exceeding the threshold value.
14. The system of claim 13 , wherein the counter is configured to decrement a count when sampled input signals do not exceed the threshold value.
15. The system of claim 10 , comprising communications circuitry configured to communicate an alarm signal to a remote monitor indicating that a bearing or wheel temperature is in excess of a desired value based upon the output.
16. The system of claim 10 , wherein the threshold value is set by an adaptive algorithm.