Method and apparatus for tri-color rail signal system with control
View Patent ↗A signaling control device apparatus ( 10 ) comprises at least one LED ( 20 ) having a light emitting surface ( 18 ). A sensor ( 24 ) is set to detect an external light load ( 16 ) directed to the light emitting surface ( 18 ) and generate a control signal indicative of a presence of the light load ( 16 ). An electrical control system ( 14 ) detects the control signal indicative of the light load ( 16 ) and sources an elevated current to the LED ( 20 ) while the light load ( 16 ) is present. The elevated current increases the contrast ratio making the signal perceivable by the users as being in a particular state.
1. A signaling control device apparatus comprising:
a light source including at least one LED, the light source having a light emitting surface;
at least one sensor set to detect an external light load directed to the light emitting surface and generate a control signal indicative of a presence of the external light load, the external light load being one of sunlight and a light from approaching train headlights; and
an electrical control system for receiving the control signal indicative of the presence of the external light load and triggering an increase in current being supplied to the at least one LED in response to the received control signal which increased current is being maintained for at least while the external light load is present;
wherein the at least one LED and the at least one sensor are disposed on a same printed circuit board; and
wherein the current is raised by pulsing the current to cause the at least one LED to pulse at a frequency higher than visually perceivable.
2. The apparatus as set forth in claim 1 , wherein the at least one sensor includes a photodiode.
3. The apparatus as set forth in claim 1 , wherein the at least one sensor detects a magnitude of the light load and wherein the control system receives a control signal indicative of a value of the magnitude of the load and generates an increased current to be supplied to the at least one LED in proportion to the load magnitude.
4. A method of controlling a signaling device, the method comprising:
providing a light source including at least one LED, the light source having a light emitting surface;
setting at least one sensor to detect an external light load directed to the light emitting surface, the external light load being one of sunlight and a light from approaching train headlights;
mounting the at least one sensor in an enclosure in a location remote from the light source;
in response to detecting a presence of the external light load, generating a control signal indicative of detecting the external light load;
receiving the control signal by an electrical control system;
triggering an increase in current being supplied to the at least one LED in response to receiving the control signal; and
maintaining the elevated current for at least while the external light load is present;
wherein the current is raised by pulsing the current to cause the at least one LED to pulse at a frequency higher than visually perceivable.
5. The method as set forth in claim 4 , wherein the at least one sensor includes a photodiode.
6. The method as set forth in claim 4 , further including:
mounting the at least one LED on a printed circuit board.
7. The method as set forth in claim 4 , further including:
one of supplying a continuous current and a pulsing current.
8. The method as set forth in claim 4 , further including:
detecting a magnitude of the light load; and
generating an output control signal indicative of a value of the light load magnitude.
9. The method as set forth in claim 8 , further including:
receiving the magnitude value by the electrical control system; and
supplying the elevated current to the at least one LED, the elevated current being proportionate to the detected light load magnitude.
10. The method as set forth in claim 9 , further including:
continually adjusting a value of the elevated current based on the detected light load magnitude.
11. The method as set forth in claim 4 , wherein the signaling device includes a rail signaling device and further including:
positioning the rail signaling device on a sharp bend; and
orienting the remotely positioned sensor along the bend towards a direction of the light of the approaching train headlights which train is approaching the rail signaling device from beyond the bend.
12. A rail signaling system comprising:
a rail signaling device including at least one LED, the rail signaling device having a light emitting surface;
at least one sensor set to detect an external light load directed to the light emitting surface and generate a control signal indicative of a presence of the external light load, the external light load being one of sunlight and a light from approaching train headlights; and
an electrical control system for receiving the control signal indicative of the presence of the external light load and triggering an increase in current being supplied to the LED in response to the received control signal which increased current is being maintained for at least while the detected external light load is present;
wherein the signaling device is positioned on a sharp bend and the sensor is in an enclosure positioned remotely from the signaling device alongside the bend so that the sensor is oriented toward the light of the approaching train headlights which train is approaching the rail signaling device from beyond the sharp bend; and
wherein the current is raised by pulsing the current to cause the at least one LED to pulse at a frequency higher than visually perceivable.