ELECTRIC SHOCK RESISTANT L.E.D. BASED LIGHT

• US 20090290334A1
• Filed: 05/23/2008
• Published: 11/26/2009
• Est. Priority Date: 05/23/2008
• Status: Active Grant

• Current Assignee: Ilumisys Incorporated (Altair Engineering Incorporated)
• Original Assignee: Altair Engineering Incorporated
• Inventors: Siemiet, Dennis, Ivey, John
• Granted Patent: US 8,360,599 B2
• Time in Patent Office: Days
• US Class Current: 362/219
• 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 9/69 Details of refractors forming part of the light source
• CPC Class Codes: F21V 23/06 the elements being coupling devices , e.g. connectors
• CPC Class Codes: F21V 25/00 Safety devices structurally associated with lighting devices gas- tight or water-tight arrangements F21V31/00; in general F16P; protective circuit arrangements per se H02H7/00
• CPC Class Codes: F21V 29/506 of globes, bowls or cover glasses
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/75 with fins or blades having different shapes, thicknesses or spacing
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/89 Metals
• 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]

Abstract

A LED-based replacement light for a fluorescent socket is constructed such that an entirety of a radially outer portion of a tubular housing at least partially defined by a high-dielectric light transmitting portion is formed of a high-dielectric material. Forming a radially outer portion of the tubular housing of a high-dielectric material prevents a person handling the light from being shocked as a result of capacitive coupling occurring when the LED-based replacement light is installed one end at a time. A circuit board is in thermally conductive relation with the tubular housing, allowing for conduction of heat generated by the LEDs from a side of circuit board opposite the LEDs to the tubular housing for dissipation to the ambient environment.

Claims

1. A shock-resistant replacement light for a conventional fluorescent tube light usable in a conventional fluorescent fixture comprising:

a generally tubular body of high-dielectric material forming the outer surface of the light over substantially its entire length;

a circuit board structure disposed within the body and thermally joined thereto while being electrically insulated therefrom;

a pair of end caps disposed on the opposite ends of the body and carrying bi-pin connectors;

an array of high-powered LEDs arranged longitudinally along the circuit board and thermally bonded thereto, the number and spacing of the LEDs being such as to uniformly and fully occupy the space between the end caps;

the body being translucent at least in part so as to permit the transmission of light from the LEDs through the body; and

at least some of the connectors on the end caps being electrically connected to the LEDs.

2. A LED-based light for replacing a conventional fluorescent light bulb in a fluorescent light fixture, the LED-based light comprising:

a tubular housing defined at least in part by a high-dielectric light transmitting portion, at least a radially outer portion of the entire tubular housing formed of a high-dielectric material;

multiple LEDs;

a circuit board structure defining a LED-mounting side and a primary heat transferring side opposite the LED-mounting side, the multiple LEDs mounted on the LED-mounting side at predetermined intervals along a length of the circuit board for emitting light through the light transmitting portion of the tubular housing, with at least areas of the primary heat transferring side directly underlying the respective LEDs in thermally conductive relation with the tubular housing for highly electrically insulated thermal transmission of heat generated by the multiple LEDs from the circuit board to an ambient environment surrounding an exterior of the tubular housing; and

at least one electrical connector at a longitudinal end of the tubular housing in electrical communication with the circuit board.

3. The LED-based light of claim 2, wherein the thermally conductive relation includes a highly thermally conductive heat spreader positioned between at least one of the areas of the primary heat transferring side directly underlying the respective LEDs and an interior surface of the tubular housing.

4. The LED-based light of claim 3, wherein the heat spreader is a monolithic mass extending substantially the length of the circuit board for conduction between all of the areas of the primary heat transferring side directly underlying the respective LEDs and the interior surface of the tubular housing.

5. The LED-based light of claim 3, wherein the heat spreader is one of multiple discrete heat spreaders spaced at the predetermined intervals along the length of circuit board for conduction between one of the areas of the primary heat transferring side directly underlying the respective LEDs and the interior surface of the tubular housing.

6. The LED-based light of claim 2, wherein the thermally conductive relation includes conduction between the entire primary heat transferring side of the circuit board and a planar interior surface of the tubular housing extending substantially the length of the circuit board.

7. The LED-based light of claim 6, wherein the tubular housing is formed of a high-dielectric light transmitting material.

8. The LED-based light of claim 2, further comprising a highly thermally conductive heat sink extending substantially a length of the tubular housing.

9. The LED-based light of claim 8, wherein the tubular housing is defined by the lens and the heat sink.

10. The LED-based light of claim 9, wherein the heat sink is made entirely of a high-dielectric, highly thermally conductive material.

11. The LED-based light of claim 8, wherein the thermally conductive relation includes conduction between the entire primary heat transferring side of the circuit board and a planar, interior surface of the heat sink extending substantially a length of the tubular housing.

12. The LED-based light of claim 8, further comprising a high-dielectric layer covering a radially outer portion of the heat sink and partially defining the tubular housing.

13. The LED-based light of claim 12, wherein the high-dielectric layer is sufficiently thick to highly insulate an exterior of the layer from a charge occurring as a result of parasitic capacitive coupling between the heat sink and the circuit board.

14. The LED-based light of claim 12, wherein the lens and high-dielectric layer define an entire exterior of the tubular housing.

15. The LED-based light of claim 2, wherein the at least one electrical connector includes two bi-pin electrical connectors, one attached to each end of the tubular housing.

16. The LED-based light of claim 2, wherein the lens includes at least two integrally formed, longitudinally extending tabs projecting parallel to a width of the circuit board from an interior of the lens, the tabs engaged with the LED-mounting side of the circuit board for securing the circuit board.

17. The LED-based light of claim 2, wherein the multiple LEDs are high-powered LEDs.

18. The LED-based light of claim 17, wherein the multiple LEDs include approximately thirty to sixty LEDs.

19. The LED-based light of claim 18, wherein the LEDs are arranged longitudinally along the circuit board and thermally bonded thereto, the spacing of the LEDs being such as to uniformly and fully occupy a length of the tubular housing.

20. A LED-based light for replacing a conventional fluorescent tube comprising:

an elongated high-dielectric translucent tube;

an elongated highly thermally conductive heat sink disposed within the tube;

an array of high-power LEDs;

a circuit board structure extending substantially the length of the heat sink, the circuit board defining a LED-mounting side of the circuit board and a primary heat transferring side of the circuit board opposite the LED-mounting side, the LEDs mounted on the LED-mounting side at predetermined intervals along the length of the circuit board for uniformly emitting light through an arc of the tube, the circuit board mounted to the heat sink with the primary heat transferring side of the circuit board in thermally conductive relation with the heat sink for highly electrically insulated thermal transmission of heat generated by the LEDs from the circuit board to an ambient environment surrounding an exterior of the tube;

a light diffusing lens positioned between the circuit board and the tube; and

a pair of end caps disposed on the opposite ends of the tube and carrying bi-pin connectors, at least some of the connectors on the end caps electrically connected to the LEDs.