LED light tube and replacement method

• US 9,228,700 B2
• Filed: 09/18/2014
• Issued: 01/05/2016
• Est. Priority Date: 06/21/2010
• Status: Expired due to Fees

• Current Assignee: LEDs America Incorporated (LEDs)
• Original Assignee: LEDs America Incorporated (LEDs)
• Inventors: Westermarck, Joel C., Kenny, Paul
• Primary Examiner(s): PHAM, THAI N
• Application Number:
  US14/489,643
• Publication Number:
  US 20150003052A1
• Time in Patent Office: 474 Days
• Field of Search: 315/51, 315/185.R, 315/246, 315/291, 315/294, 362/218, 362/221, 362/223, 362/225, 362/217.1, 362/240, 362/249.02, 362/800
• US Class Current: 1/1
• CPC Class Codes: F21K 9/27 Retrofit light sources for lighting devices with two fittings for each light source, e.g. for substitution of fluorescent tubes
• CPC Class Codes: F21K 9/278 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21K 9/90 Methods of manufacture
• CPC Class Codes: F21V 21/005 for several lighting devices in an end-to-end arrangement, i.e. light tracks
• CPC Class Codes: F21V 23/023 Power supplies in a casing F21V23/003 takes precedence
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2105/12 characterised by the geometrical disposition of the light-generating elements, e.g. arranging light-generating elements in differing patterns or densities
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

LED light tube replaces a fluorescent light mounted in a fluorescent light fixture. Main power is feed only to the first socket end mount of the fluorescent fixture. The LED light tube includes an elongated tubular structure substantially the size and length of the fluorescent light tube and extends between the first and second end mounts of the fixture. Within an end region of the tubular structure and adjacent the first tube end mount, an internal power supply converts the main line power to LED bank power. The tubular structure of the LED light includes an elongated semi-spherical substantially transparent top cover mounted atop a printed circuit board substrate. The substrate supports a plurality of LEDs thereon.

Claims

1. An LED light tube for replacing a fluorescent light tube mounted in a fluorescent light tube fixture, said fluorescent light tube fixture having first and second socket end mounts, each end mount mechanically accepting a common fixture connector for said fluorescent light tube, said fluorescent light tube fixture being supplied with main line power, said main line power being 110 volts to 277 volts, comprising:

a power and a neutral wire connection from said main line power to the first socket end mount in the light fixture and an open circuit between said main line power and the second socket end mount;

an elongated tubular structure substantially the size and length of said fluorescent light tube and extending between said first and second end mounts;

within an end region of said tubular structure and adjacent said first socket end mount, an internal power supply for converting said main line power to LED bank power, said internal power supply electrically coupled to said main line power via said first socket end mount;

said internal power supply being a form fitting, Class 2 power supply with a transformer no larger than 25×

22×

22 mm in size, the Class 2 power supply converts 120-277 v AC (50-60 Hz;

0.061-0.14 A) to 15 w, 31 v DC which is the LED drive voltage for no more than 280 LEDs;

said tubular structure including;

an elongated hemispherical substantially transparent tube cover mounted atop a printed circuit board substrate, said substrate supporting a plurality of no more than 280 LEDs, said tube cover and LED supporting substrate extending the length of said tubular structure other than said at said end region;

an elongated hemispherical metal cover mounted below the printed circuit board substrate and beneath said plurality of LEDs as a heat sink; and

an electrical system within said tubular structure suppling said LED bank power to said plurality of LEDs on said substrate.

2. An LED light tube as claimed in claim 1 wherein said substrate disposed substantially along an axial center line of said tubular structure.

3. An LED light tube as claimed in claim 1 said tubular structure has first and second end caps which are mechanically complementary to said first and second socket end mounts, said first end cap electrically coupled to said main line power at said first socket end and said second end cap not electrically coupled to said main line power at said second socket end.

4. An LED light tube as claimed in claim 1 wherein each LED of said plurality of LEDS has a pair of terminals, and the LED light tube includes a group of heat sink strips beneath each terminal for each LED, each group of heat sink strips being a local heat sink for the respective LED terminal.

5. An LED light tube as claimed in claim 4 wherein said heat sink strips are beneath the circuit board substrate and are thermally adjacent said metal cover and said plurality of LEDS mounted on a topside of said substrate.

6. An LED light tube as claimed in claim 1 wherein at least 250 LEDs are supported on said substrate.

7. An LED light tube as claimed in claim 1 including an opaque end region cover over said power supply.

8. An LED light tube as claimed in claim 1 wherein said LEDs are not uniformly spaced apart on said substrate.

9. An LED light tube as claimed in claim 8 wherein a first sub-plurality of said plurality of LEDs are closely spaced together and a second sub-plurality of said plurality of LEDs are spaced a greater distance apart.

10. An LED light tube as claimed in claim 1 wherein said metal cover is electrically isolated from said printed circuit board substrate by one or more insulators.

11. An LED light tube as claimed in claim 1 wherein said metal cover is electrically isolated from said printed circuit board substrate by an elongated insulator substantially extending the length of said tubular structure.

12. An LED light tube as claimed in claim 1 wherein said metal cover is electrically isolated from said printed circuit board substrate by a pair of elongated insulators substantially extending the length of said tubular structure between said printed circuit board substrate and said metal cover.

13. An LED light tube as claimed in claim 1 wherein said transparent cover is exposed the ambient environment and said metal cover is exposed the ambient environment to respectively transmit light from the LEDs and to transmit heat from the LEDs.

20. An LED light tube as claimed in claim 1 wherein said metal cover is electrically isolated from said printed circuit board substrate by either a singular elongated insulator substantially extending the length of said tubular structure or by a pair of elongated insulators substantially extending the length of said tubular structure between said printed circuit board substrate and said metal cover, and said transparent cover is exposed the ambient environment and said metal cover is exposed the ambient environment to respectively transmit light from the LEDs and to transmit heat from the LEDs.

14. An LED light tube adapted to replace a fluorescent light tube mounted in a fluorescent light tube fixture, said fluorescent light tube fixture having first and second socket end mounts, each end mount mechanically accepting a common fixture connector for said fluorescent light tube, said fluorescent light tube fixture being supplied with main line power, said main line power being 110 volts to 277 volts and being fed to the first socket end mount in the light fixture with an open circuit between said main line power and the second socket end mount, the LED light tube comprising:

an elongated tubular structure substantially the size and length of said fluorescent light tube and extending between said first and second end mounts;

within an end region of said tubular structure and adjacent said first socket end mount, an internal power supply for converting said main line power to LED bank power, said internal power supply electrically coupled to said main line power via said first socket end mount;

said internal power supply being a form fitting, Class 2 power supply with a transformer no larger than 25×

22×

22 mm in size, the Class 2 power supply converts 120-277 v AC (50-60 Hz;

0.061-0.14 A) to 15 w, 31 v DC which is the LED drive voltage for no more than 280 LEDs;

said tubular structure including;

an elongated hemispherical substantially transparent tube cover mounted atop a printed circuit board substrate, said substrate supporting a plurality of no more than 280 LEDs, said tube cover and LED supporting substrate extending the length of said tubular structure other than said at said end region;

an elongated hemispherical metal cover mounted below the printed circuit board substrate and beneath said plurality of LEDs as a heat sink; and

an electrical system within said tubular structure suppling said LED bank power to said plurality of LEDs on said substrate.

15. An LED light tube as claimed in claim 14 wherein said substrate disposed substantially along an axial center line of said tubular structure, and said tubular structure has first and second end caps which are mechanically complementary to said first and second socket end mounts, said first end cap electrically coupled to said main line power at said first socket end.

16. An LED light tube as claimed in claim 14 wherein each LED of said plurality of LEDS has a pair of terminals, and the LED light tube includes a group of heat sink strips beneath each terminal for each LED, each group of heat sink strips being a local heat sink for the respective LED terminal and wherein said heat sink strips are beneath the circuit board substrate and are thermally adjacent said metal cover.

17. An LED light tube as claimed in claim 14 including an opaque end region cover over said power supply.

18. An LED light tube as claimed in claim 14 wherein said LEDs are not uniformly spaced apart on said substrate and wherein a first sub-plurality of said plurality of LEDs are closely spaced together and a second sub-plurality of said plurality of LEDs are spaced a greater distance apart.

19. An LED light tube as claimed in claim 14 wherein said metal cover is electrically isolated from said printed circuit board substrate by one or more insulators.

21. An LED light tube adapted to replace a fluorescent light tube mounted in a fluorescent light tube fixture, said fluorescent light tube fixture having first and second socket end mounts, each end mount mechanically accepting a common fixture connector for said fluorescent light tube, said fluorescent light tube fixture being supplied with main line power, said main line power being 110 volts to 277 volts and being fed to the first socket end mount in the light fixture with an open circuit between said main line power and the second socket end mount, the LED light tube comprising:

an elongated tubular structure substantially the size and length of said fluorescent light tube and extending between said first and second end mounts;

within a defined region of said tubular structure and electrically connected to said first socket end mount, an internal power supply for converting said main line power to LED bank power, said internal power supply electrically coupled to said main line power via said first socket end mount, said defined region being intermediate said first and second end mounts;

said internal power supply being a form fitting, Class 2 power supply with a transformer no larger than 25×

22×

22 mm in size, the Class 2 power supply converts 120-277 v AC (50-60 Hz;

0.061-0.14 A) to 15 w, 31 v DC which is the LED drive voltage for no more than 280 LEDs;

said tubular structure including;

an elongated hemispherical substantially transparent tube cover mounted atop a printed circuit board substrate, said substrate supporting a plurality of no more than 280 LEDs, said tube cover and LED supporting substrate extending the length of said tubular structure other than said at said defined region;

an elongated substantially metal cover mounted below the printed circuit board substrate and beneath said plurality of LEDs as a heat sink;

an electrical system within said tubular structure suppling said LED bank power to said plurality of LEDs on said substrate; and

said internal power supply mounted on said printed circuit board substrate.

22. An LED light tube as claimed in claim 21 wherein said substrate disposed substantially along an axial center line of said tubular structure, and said tubular structure has first and second end caps which are mechanically complementary to said first and second socket end mounts, said first end cap electrically coupled to said main line power at said first socket end.

23. An LED light tube as claimed in claim 21 wherein each LED of said plurality of LEDS has a pair of terminals, and the LED light tube includes a group of heat sink strips beneath each terminal for each LED, each group of heat sink strips being a local heat sink for the respective LED terminal and wherein said heat sink strips are beneath the circuit board substrate and are thermally adjacent said metal cover.

24. An LED light tube as claimed in claim 21 including an opaque end region cover over said power supply.

25. An LED light tube as claimed in claim 21 wherein said LEDs are not uniformly spaced apart on said substrate and wherein a first sub-plurality of said plurality of LEDs are closely spaced together and a second sub-plurality of said plurality of LEDs are spaced a greater distance apart.

26. An LED light tube as claimed in claim 21 wherein said metal cover is electrically isolated from said printed circuit board substrate by one of:

a plurality of insulators;

a singular elongated insulator substantially extending the length of said tubular structure;

or

a pair of elongated insulators substantially extending the length of said tubular structure between said printed circuit board substrate and said metal cover; and

wherein said transparent cover is exposed the ambient environment and said metal cover is exposed the ambient environment to respectively transmit light from the LEDs and to transmit heat from the LEDs.

27. A method of replacing a fluorescent light tube with an LED light tube adapted to be mounted in a fluorescent light tube fixture, said fluorescent light tube fixture having first and second socket end mounts, each end mount mechanically accepting a common fixture connector for said fluorescent light tube, said fluorescent light tube fixture being supplied with main line power, said main line power being 110 volts to 277 volts, comprising:

connecting a power and a neutral wire from said main line power to the first socket end mount in the light fixture;

opening the electric circuit between said main line power and the second socket end mount;

providing an elongated tubular structure substantially the size and length of said fluorescent light tube with end caps complementary to said first and second end mounts, said tubular structure having an end region adjacent said first socket end mount, an internal power supply for converting said main line power to LED bank power, an elongated hemispherical substantially transparent tube cover mounted atop a printed circuit board substrate, a plurality of no more than 280 LEDs on the substrate and extending the length of said tubular structure other than said at said end region, and an elongated hemispherical metal cover mounted below the printed circuit board substrate and beneath said plurality of LEDs as a heat sink;

said internal power supply being a form fitting, Class 2 power supply with a transformer no larger than 25×

22×

22 mm in size, the Class 2 power supply converts 120-277 v AC (50-60 Hz;

0.061-0.14 A) to 15 w, 31 v DC which is the LED drive voltage for no more than 280 LEDs;

suppling said LED bank power to said plurality of LEDs on a said substrate;

illuminating the length of said elongated tubular structure except for said end region;

dissipating heat generated from said LEDs via (a) the hollow space between said substrate and said metal cover and (b) the metal cover; and

electrically isolating said substrate from said metal cover.