Abstract: An electrically driven light emitting diode (LED) assembly and the method of assembling same. The assembly includes an electrically and thermally conductive heat dissipater (10) sandwiched under an electrically insulating layer (12) with circuit traces (14) disposed over the insulating layer (12) to prevent electrical conduction between the traces (14) and the heat dissipater (10). A plurality of light emitting diodes (20) have electrical leads (22) extending laterally from opposite extremities of each LED (20) to overlie the traces (14) for electrical contact with the traces (14) for powering the LEDs (20). An independent and generally U-shaped holding device (24, 26, 28, 30 and 32), as viewed in cross section, defines a base overlying the LED (20) and a pair of legs (36, 136) depending therefrom and transversely to the electrical leads (22) between the LED (20) and the heat dissipater (10). The base defines a hole (38) and the LED (20) protrudes (39) through the hole (38) to emit light.

Abstract: An electrically driven light emitting diode (LED) assembly comprising a light emitting diode (12), first (14) and second (16) electrical leads for conducting electricity to and from the light emitting diode (12), and a heat sink (18). The assembly is characterized by the first lead (14) including the heat sink (18) for conducting electricity and heat from the light emitting diode (12) through the heat sink (18). In other words, the diode (12) conducts electricity through a heat sink (18) allowing the diode (12) to be in electrical conductivity with the heat sink (18).

Abstract: A heat dissipater (30) of a metallic or metal material is disposed in parallel relationship to a circuit board (12). The assembly is characterized by the circuit board 12 presenting a hole (32) therethrough and surrounding each of a plurality of LEDs (20, 22 or 24). A heat sink (28) integral with each LED (20, 22 or 24) is disposed in thermal contact with the heat dissipater (30) for conveying heat from the LEDs (20, 22 and 24) to the heat dissipater (30). In other words, each LED (20, 22 or 24) extends through the hole (32) in the circuit board (12) with the light emitting portion or lens (34) extending from one of the surfaces (14 or 16) of the circuit board (12) and the heat sink (28) extending from the other one of the surfaces (14 or 16) of the circuit board (12). A thermal coupling agent (36 or 38) is disposed between the heat sink (28) and the heat dissipater (30) for providing a full thermal path between the heat sink (28) and the heat dissipater (30). In FIG.

Abstract: An electrically driven light emitting diode (LED) assembly comprising a light emitting diode (12), first (14) and second (16) electrical leads for conducting electricity to and from the light emitting diode (12), and a heat sink (18). The assembly is characterized by the first lead (14) including the heat sink (18) for conducting electricity and heat from the light emitting diode (12) through the heat sink (18). In other words, the diode (12) conducts electricity through a heat sink (18) allowing the diode (12) to be in electrical conductivity with the heat sink (18).

Abstract: A transformer T1 having a primary winding and a secondary winding each having a plurality of turns 12 and 14 and a plurality of taps 16, 18, 20, 22 and 24 for changing the number of effective turns 12 and 14 of the primary winding. An array of LEDs 36 produce a luminous output in response to power supplied by the transformer T1. The assembly is characterized by a controller 38 for automatically selecting one of the taps 16, 18, 20, 22 or 24 in response to an operating parameter of the LEDs 36 for maintaining the luminous output of said LEDs 36 above a predetermined level. The measurement of the operating parameter may be any one of or any combination of measuring voltage across the LEDs 36, measuring current through the LEDs 36, measuring the temperature of the LEDs 36, or measuring 40 the luminous output of the LEDs 36.

Abstract: An electrically driven L.E.D. lamp assembly (14) comprising an electrically insulating circuit board (26) having opposed first and second surfaces with light emitting diodes (28) having positive and negative leads (30, 32) mounted on the first surface. A plurality of holes extend through the board (26) and a plurality of pads (50) of thermally conductive plating are disposed on the second side with each pad (50) associated with the leads to conduct heat from each of the leads to one of the pads (50) while maintaining electrical isolation between the pads. A heat sink includes a base (36) overlying the second surface and an adhesive layer (58) of thermally conductive adhesive is disposed between the conductive plating and the heat sink (36) to secure the conductive plating and the circuit board (26) to the heat sink (36).

Abstract: A method of manufacturing an electrically driven L.E.D. lamp assembly (10) comprising the steps of screen printing an electrically insulating coating (16) which can be of less than two hundred microns thickness over an electrically and thermally conductive heat sink, i.e., aluminum, and printing circuit traces 18 of a resin with metal dispersed therein in end to end relationship on the routes of insulating coating 16 to establish discrete and electrically conductive paths for electrically interconnecting light emitting diodes 20. The light emitting diodes 20 are adhesively secured to the ends of adjacent circuit traces 18 with an electrically conductive adhesive 26 comprising an organic polymeric material compounded with a metal.

Abstract: A circuit for maintaining the luminous intensity of a light emitting diode (LED) (12) comprising at least one light emitting diode (LED) (12) for producing an luminous intensity; a sensor (22,24) for sensing a condition proportional to the luminous intensity of the LED (12) and for producing a luminous intensity signal; a power supply (16) electrically connected to the LED (12) for supplying pulses of electrical energy to the LED (12); and wherein the power supply (16) includes a switching device responsive to the luminous intensity signal for adjusting the electrical energy supplied by the pulses per unit of time to adjust the average of the current passing through the LED (12) to maintain the luminous intensity of the LED (12) at a predetermined level. In one instance, the sensor (22) includes means for sensing changes in the operating temperature of the LED (12). In a second instance, the sensor (24) includes means (28) for sensing changes in luminous output of the LED (12).

Abstract: An apparatus (10) for supplying regulated voltage d.c. electrical power to an LED array (12) includes a rectifier (32) responsive to a.c. power for generating rectified d.c. power and a power factor correcting and voltage regulating buck/boost switchmode converter (38) responsive to the rectified d.c. power for generating regulated voltage d.c. power to illuminate the LED array (12). A battery backup system (62) receives the a.c. power applied to the rectifier (32) for charging a rechargeable battery (66) and sensing an a.c. power failure. A switch-over relay (82) is connected between the battery backup system (62) and the rectifier. Upon sensing a failure of the a.c. power, the battery backup system (62) controls the switch-over relay (82) to connect the battery backup system (62) to the rectifier (32) to provide d.c. power to the switchmode converter (38) to illuminate the LED array (12). A half wave power detector (88) causes the apparatus (10) to reduce regulated d.c. power to dim the LED array (12).