LED based light engine

• US 7,784,969 B2
• Filed: 10/30/2006
• Issued: 08/31/2010
• Est. Priority Date: 04/12/2006
• Status: Expired due to Fees

• Current Assignee: Tall Tower Led, LLC
• Original Assignee: Bhc Interim Funding II, L.P.
• Inventors: Reisenauer, William, Fusco, Michael, Pawelko, Wojciech
• Primary Examiner(s): Choi; Jacob Y
• Assistant Examiner(s): Makiya; David J
• Application Number:
  US11/589,548
• Publication Number:
  US 20070242461A1
• Time in Patent Office: 1,401 Days
• Field of Search: 362/294, 362/373, 362/650
• US Class Current: 362/294
• CPC Class Codes: F21K 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21K 9/238 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21V 23/006 the substrate being distinct from the light source holder
• CPC Class Codes: F21V 25/10 coming into action when lighting device is overloaded, e.g. thermal switch
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/75 with fins or blades having different shapes, thicknesses or spacing
• CPC Class Codes: F21V 29/773 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/87 Organic material, e.g. filled polymer composites; Thermo-conductive additives or coatings therefor
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/325 Pulse-width modulation [PWM]
• CPC Class Codes: H05B 45/355 Power factor correction [PFC]; Reactive power compensation
• CPC Class Codes: H05B 45/3574 Emulating the electrical or functional characteristics of incandescent lamps
• CPC Class Codes: H05B 45/36 Circuits for reducing or suppressing harmonics, ripples or electromagnetic interferences [EMI]
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

A light emitting diode (LED) based light engine that can replace a conventional PAR type bulb with no modifications to a host lighting fixture is provided. The light engine includes a thermally conductive housing including a generally cylindrical wall defining a cavity, an outer surface of the wall includes a plurality of axially radiating fins and disposed on an inner surface of the wall is an annular center wall dividing the cavity into a first, upper cavity and a second, lower cavity; a light module including at least one LED is disposed in the first, upper cavity and configured to contact the annular center wall, wherein heat generated by the at least one LED is disposed in the second, lower cavity and electrically coupled to the light module.

Claims

1. A light engine comprising:

a thermally conductive housing configured for supporting a light module and a current driver circuit and for conducting heat away from the light module and the current driver circuit, the housing including a generally cylindrical wall disposed along a longitudinal axis of the housing and defining a cavity, the cylindrical wall includes an inner surface and an outer surface, a plurality of fins radiating outwardly from the outer surface of the cylindrical wall, each of the plurality of fins running length-wise parallel to the longitudinal axis of the housing, and an annular center wall extending inwardly from the inner surface of the cylindrical wall being substantially perpendicular to the longitudinal axis of the housing and dividing the cavity into a first, upper cavity and a second, lower cavity;

the light module including at least one light emitting diode (LED) for producing visible light mounted to a circular metal core printed circuit board, the light module completely disposed in the first, upper cavity and the circular metal core printed circuit board being substantially in full contact with an upper surface of the annular center wall, wherein heat generated by the at least one LED is conducted to the housing via the circular metal core printed circuit board;

the current driver circuit arranged on a substrate having an upper portion of a first width tapering to a lower portion of a second width, the first width being greater than the second width, the upper portion including two side walls configured to come into contact with the inner surface of the second, lower cavity of the base, the upper portion further including a tab, with output terminals, dimensioned to fit into an aperture of the annular center wall to facilitate an electrical connection between the output terminals and the at least one LED, the lower portion extending away from the housing along the longitudinal axis; and

a base configured for receiving input power and coupling the input power to the current driver circuit, the base being dimensioned to be disposed over the lower portion of the current driver circuit substrate with an interference fit.

2. The light engine as in claim 1, further comprising a lens for sealing the light module within the housing, the lens being configured to mate to an open end of the first, upper cavity.

3. The light engine as in claim 2, further comprising a trim ring configured to be disposed about the lens for securing the lens to the open end of the housing.

4. The light engine as in claim 1, further comprising an optical element disposed over the at least one LED for channeling light emitting from the at least one LED.

5. The light engine as in claim as in claim 1, wherein the housing is aluminum or thermally conductive plastic.

6. The light engine as in claim 1, wherein at least two diametrically opposed fins include a cut away portion to define a grip area to facilitate installation.

7. The light engine as in claim 1, wherein a lower portion of the current driver circuit substrate is configured to be disposed in the base.

8. The light engine as in claim 1, wherein the housing is configured from an electrically conductive metal.

9. The light engine as in claim 8, wherein the substrate of the current driver circuit is ground to the housing, wherein the housing acts as a Faraday shield for suppression of related electromagnetic interference (EMI).

10. The light engine as in claim 1, further comprising a temperature sensor coupled to the current driver circuit, wherein if the sensed temperature arises above a predetermined threshold value, the current driver circuit reduces or shuts off current to the light module.