Light tube and power supply circuit

• US 7,049,761 B2
• Filed: 02/12/2001
• Issued: 05/23/2006
• Est. Priority Date: 02/11/2000
• Status: Expired due to Term

• Current Assignee: Ilumisys Incorporated (Altair Engineering Incorporated)
• Original Assignee: Altair Engineering Incorporated
• Inventors: Timmermans, Jos, Raymond, Jean C.
• Primary Examiner(s): Lee, Wilson
• Assistant Examiner(s): Tran, Chuc
• Application Number:
  US09/782,375
• Publication Number:
  US 20020060526A1
• Time in Patent Office: 1,926 Days
• Field of Search: 315/146, 315/291, 315/185.S, 315/312, 315/324, 315/192, 315/185.R, 315/295, 315/246, 315/187, 315/294, 315/56, 315/200.A, 315/61, 340/815.45, 362/488, 362/240, 362/219, 362/800, 362/369, 362/545, 362/288, 362/249
• US Class Current: 315/246
• CPC Class Codes: B60Q 3/80 Circuits; Control arrangements for dashboards B60Q3/16; for mass transit vehicles B60Q3/47
• CPC Class Codes: F21K 9/272 Details of end parts, i.e. the parts that connect the light source to a fitting; Arrangement of components within end parts F21K9/278 takes precedence
• CPC Class Codes: F21K 9/275 Details of bases or housings, i.e. the parts between the light-generating element and the end caps; Arrangement of components within bases or housings F21K9/278 takes precedence
• CPC Class Codes: F21K 9/278 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21K 9/66 Details of globes or covers forming part of the light source
• CPC Class Codes: F21K 9/90 Methods of manufacture
• CPC Class Codes: F21S 4/28 rigid, e.g. LED bars
• CPC Class Codes: F21V 15/015 Devices for covering joints between adjacent lighting devices; End coverings
• CPC Class Codes: F21V 19/003 Fastening of light source holders, e.g. of circuit boards or substrates holding light sources
• CPC Class Codes: F21V 19/008 of straight tubular light sources, e.g. straight fluorescent tubes, soffit lamps
• CPC Class Codes: F21V 23/00 Arrangement of electric circuit elements in or on lighting devices characterised by cooling arrangements F21V29/508
• CPC Class Codes: F21V 23/009 the casing being inside the housing of the lighting device
• CPC Class Codes: F21V 23/02 the elements being transformers, impedances or power supply units, e.g. a transformer with a rectifier
• CPC Class Codes: F21V 23/023 Power supplies in a casing F21V23/003 takes precedence
• CPC Class Codes: F21V 23/06 the elements being coupling devices , e.g. connectors
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 25/13 the devices being of a type provided for in group H01L33/00
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05B 45/10 : Controlling the intensity of the light
• CPC Class Codes: H05B 45/14 : using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 45/325 : Pulse-width modulation [PWM]
• CPC Class Codes: H05B 45/3578 : Emulating the electrical or functional characteristics of discharge lamps
• CPC Class Codes: H05B 45/3725 : Switched mode power supply [SMPS]
• CPC Class Codes: H05B 47/10 : Controlling the light source
• CPC Class Codes: Y02B 20/30 : Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

The present invention provides a light tube for illumination by a power supply circuit including a bulb portion and a pair of end caps disposed at opposite ends of the bulb portion. A plurality of light emitting diodes are disposed inside the bulb portion and in electrical communication with the pair of end caps for illuminating in response to electrical current to be received from the power supply circuit.

Claims

1. A light device for illumination by a power supply circuit comprising:

a bulb portion,

a first end cap disposed at one end of the bulb portion,

a second end cap disposed at an end of bulb portion opposite the first end cap, the first and second end caps forming a pair of end caps on opposite ends of the bulb portion; and

wherein the bulb portion and the pair of end caps are dimensioned to be mounted in a fluorescent light tube socket, and

a plurality of light emitting diodes disposed inside the bulb portion, the light emitting diodes in electrical communication with the end cap for illuminating in response to electrical current received from the power supply circuit, and wherein the plurality of light emitting diodes is mounted an at least one circuit board; and

wherein each of the plurality of light emitting diodes is mounted at an angular off-set from the circuit board to establish a predetermined radiation pattern of light.

6. The light device of claim 1 wherein the plurality of light emitting diodes is mounted on only one side of the at least one circuit board.

7. The light device of claim 6 wherein the radiation pattern of light from each of the plurality of light emitting diodes is centered at a 90°

angle relative to the at least one circuit board.

8. The light device of claim 1 wherein each of the plurality of light emitting diodes is a white LED.

9. The light device of claim 1, wherein the plurality of light emitting diodes is displaced substantially continuously between the opposite ends of the bulb portion.

18. The light device of claim 1 wherein the bulb portion comprises one of clear glass and frosted glass.

23. The light device of claim 1 wherein each of the plurality of light emitting diodes is arranged into one of a plurality of spaced light emitting diode banks, each of the plurality of light emitting diode banks comprising at least two light emitting diodes.

2. A light tube for illumination by a power supply circuit comprising:

a bulb portion,

a first of end caps disposed at opposite ends of the bulb portion, wherein each of the pair of end caps is shaped to be coupled with a fluorescent light tube socket, and

a plurality of closely-spaced light emitting diodes disposed inside the bulb portion and extending between the opposite ends of the bulb portion, the light emitting diodes in electrical communication with the pair of end caps for illuminating in response to electrical current received from the power supply circuit; and

wherein each of the pair of end caps is an electrical bi-pin connector.

3. In a replacement light tube for a fluorescent light fixture having a light tube socket and a power supply circuit, the improvement comprising:

a plurality of closely-spaced light emitting diodes disposed inside a bulb portion of the light tube and in electrical communication with a pair of end caps coupled to opposed ends of the bulb portion and engageable with the light tube socket, the plurality of light emitting diodes operable to illuminate in response to electrical current delivered by the fluorescent light; and

wherein each of the pair of end caps is an electrical bi-pin connector.

4. The improvement of claim 3, wherein the plurality of light emitting diodes is mounted to a circuit board.

5. The improvement of claim 4, wherein each of the plurality of light emitting diodes is mounted at an angular off-set from the circuit board to establish a predetermined radiation pattern of light.

11. The improvement of claim 3 wherein the bulb portion is annular.

12. The improvement of claim 3 wherein the electric current is a direct current signal, the improvement further comprising:

a rectifier for converting an alternating current signal from the fluorescent light fixture to the direct current signal.

14. The improvement of claim 3 wherein each of the plurality of light emitting diodes is a white LED.

16. The improvement of claim 4 wherein the plurality of light emitting diodes is mounted on only one side of the circuit board to emit light toward only one side of the bulb portion.

17. The improvement of claim 16 wherein the radiation pattern of light from each of the plurality of light emitting diodes is centered at a 90°

angle relative to the circuit board.

24. The improvement of claim 3 wherein each of the plurality of light emitting diodes is arranged into one of a plurality of spaced light emitting diode banks, each of the plurality of light emitting diode banks comprising at least two light emitting diodes.

25. The improvement of claim 24 wherein each of the plurality of spaced light emitting diode banks is spaced equidistant from adjacent ones of the plurality of spaced light emitting diode banks.

10. A light device for illumination by a power supply circuit comprising:

a bulb portion,

a first end cap disposed at one end of the bulb portion, and

a plurality of light emitting diodes disposed inside the bulb portion, the light emitting diodes in electrical communication with the end cap for illumination in response to electrical current received from the power supply circuit; and

wherein the plurality of light emitting diodes is mounted on at least one circuit board; and

wherein each of the plurality of light emitting diodes is mounted at an angular off-set from the circuit board to establish a predetermined radiation pattern of light; and

wherein each of the plurality of light emitting diodes is arranged into one of a plurality of equidistantly-spaced light emitting diode banks, each of the plurality of light emitting diode banks comprising at least two light emitting diodes.

13. In a replacement light tube for a flourescent light fixture having a light tube socket and a power supply circuit, the improvement comprising:

a plurality of closely-spaced light emitting diodes disposed inside a bulb portion of the light tube and in electrical communication with a pair of end caps coupled to opposed ends of the bulb portion and engageable with the light tube socket, the plurality of light emitting diodes operable to illuminate in response to electrical current delivered by the flourescent light fixture wherein the electric current is a direct current signal;

a rectifier for converting an alternating current signal from the fluorescent light fixture to the direct current signal; and

a pulse-width modulating circuit for receiving the direct current signal and supplying a resulting modulated signal to the plurality of light emitting diodes.

15. In a replacement light tube for a flourescent light fixture having a light tube socket and a power supply circuit, the improvement comprising:

a plurality of closely-spaced light emitting diodes disposed inside a bulb portion of the light tube and in electrical communication with a pair of end caps coupled to opposed ends of the bulb portion and engageable with the light tube socket, the plurality of light emitting diodes operable to illuminate in response to electrical current delivered by the flourescent light fixture; and

wherein each of the plurality of light emitting diodes is arranged into one of a plurality of spaced light emitting diode banks, each of the plurality of light emitting diode banks comprising at least two light emitting diodes.

26. The improvement of claim 15 wherein each of the plurality of spaced light emitting diode banks is spaced equidistant from adjacent ones of the plurality of spaced light emitting diode banks.

19. A retrofit LED light tube for replacing a light tube in a fixture, the retrofit LED light tube comprising:

a elongated cylindrical transparent envelope,

a base cap at an end of the envelope, wherein the base cap is an electrical bi-pin connector comprising a first pin and a second pin extending perpendicularly from a surface of the base cap, wherein the first and second pins are adapted to electrically communicate with a fluorescent light socket; and

at least one LED device in electrical communication with the base cap, wherein the at least one LED device is electrically connected to a rectifier and the at least one LED device is further electrically connected to a pulse-width modulating circuit receiving a direct current signal from the rectifier and supplying a modulated signal to the at least one LED device.

20. The retrofit light tube of claim 19, wherein the LED device comprises a circuit board and a plurality of LEDs serially connected to the circuit board.

21. The retrofit light tube of claim 19, further comprising:

current-limiting means coupled to the at least one LED device.

22. The retrofit light tube of claim 19 wherein the base cap has circuitry means for connection with an AC source.