LENS HEATING SYSTEMS AND METHODS FOR AN LED LIGHTING SYSTEM

• US 20160363286A1
• Filed: 06/15/2016
• Published: 12/15/2016
• Est. Priority Date: 06/15/2015
• Status: Active Grant

• Current Assignee: J.W. Speaker, Corporation
• Original Assignee: J.W. Speaker, Corporation
• Inventors: DEERING, ERIC
• Granted Patent: US 10,364,954 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F21S 41/153 arranged in a matrix
• CPC Class Codes: F21S 41/28 Cover glass
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 45/60 Heating of lighting devices, e.g. for demisting
• CPC Class Codes: F21W 2102/00 Exterior vehicle lighting devices for illuminating purposes
• CPC Class Codes: H05B 2203/011 Heaters using laterally extending conductive material as connecting means
• CPC Class Codes: H05B 2203/013 Heaters using resistive films or coatings
• CPC Class Codes: H05B 2203/02 Heaters using heating elements having a positive temperature coefficient
• CPC Class Codes: H05B 3/84 Heating arrangements specially adapted for transparent or reflecting areas, e.g. for demisting or de-icing windows, mirrors or vehicle windshields

Abstract

Systems and methods for lighting system lens heating are described. The systems and methods include a substantially clear thermoplastic substrate; and a conductive ink or film circuit on the thermoplastic substrate.

Claims

1. A heating system for heating the lens of a lighting system, the heating system comprising:

a substantially clear thermoplastic substrate; and

a conductive ink or film circuit on the thermoplastic substrate.

2. The heating system according to claim 1, further including a lens heater circuit, with a lens heater controller operatively coupled to the lens heater circuit.

3. The heating system according to claim 1, wherein the conductive ink circuit is screen printed on the thermoplastic substrate.

4. The heating system according to claim 1, wherein the conductive ink circuit is a conductive silver trace.

5. The heating system according to claim 1, wherein the conductive film circuit is a conductive silver trace.

6. The heating system according to claim 1, wherein a heating output of the conductive ink circuit is regulated based upon the temperature of the conductive ink circuit utilizing a positive temperature coefficient (PTC) ink trace.

7. The heating system according to claim 1, further including a dielectric top coating on the conductive ink circuit.

8. The heating system according to claim 1, wherein the conductive ink circuit has a resistance in the range of about 5 ohms to about 300 ohms.

9. The heating system according to claim 1, wherein the conductive ink circuit includes traces that are generally equal length.

10. The heating system according to claim 9, wherein the traces are connected with a busbar on a non-power connect side.

11. The heating system according to claim 9, wherein the traces have a width in the range of about 0.05 mm to about 1.0 mm.

12. The heating system according to claim 1, wherein the conductive ink circuit produces about 1 W/in̂

2.

13. The heating system according to claim 1, wherein the conductive ink circuit is a substantially transparent ink.

14. The heating system according to claim 1, wherein the lens heater controller regulates the conductive ink circuit voltage to increase or decrease the power being dissipated by the conductive ink circuit.

15. The heating system according to claim 1, further including a lighting system lens, wherein the conductive ink circuit remains exposed on the inside of the lighting system lens.

16. An LED lighting system having a heated lens, the LED lighting system comprising:

a housing, the housing including a base and a lens, the lens having a interior lens side and an exterior lens side;

at least one LED positioned within the base to provide illumination through the lens;

a lens heater controller;

a lens heater circuit operatively coupled to the lens heater controller;

a substantially clear thermoplastic substrate positioned on the interior lens side; and

a conductive ink or film circuit on the thermoplastic substrate operatively coupled to the lens heater circuit.

17. The LED lighting system according to claim 16, wherein the conductive ink on the thermoplastic substrate is placed into a pocket on a core of an injection molding tool with the conductive ink side against the core, and the conductive ink side remains exposed on a final lighting system lens part.

18. The LED lighting system according to claim 16, wherein the conductive ink on the thermoplastic substrate is placed against a cavity side of an injection molding tool, with the conductive ink side encapsulated between the thermoplastic substrate and a final lighting system lens part.

19. The LED lighting system according to claim 17, wherein a thermoplastic resin then over molds the thermoplastic substrate, bonding only to the non-printed side of the thermoplastic substrate.

20. The LED lighting system according to claim 17, wherein the injection molding tool uses vacuum to recess and hold the thermoplastic substrate in the core.

21. The LED lighting system according to claim 16, wherein greater than 90 percent transmission rate in terms of both lumens and intensity is achieved.

22. A method for heating a lens of a lighting system, the method comprising:

applying a conductive ink or film circuit on a substantially clear thermoplastic substrate;

applying the conductive ink or film circuit on the substantially clear thermoplastic substrate to at least one of an interior lens side and an exterior lens side; and

applying a controlled power to the conductive ink or film circuit to heat the lens.

23. The method according to claim 22, further including applying a PTC trace near the conductive ink or film circuit;

sensing the resistance of the PTC trace; and

controlling the power to the conductive ink or film circuit based on the sensed resistance of the PTC trace.