LED assemblies and light strings containing same

• US 20060007679A1
• Filed: 09/16/2005
• Published: 01/12/2006
• Est. Priority Date: 08/28/1998
• Status: Active Grant

• Current Assignee: Fiber Optic Designs Incorporated
• Original Assignee: Fiber Optic Designs Incorporated
• Inventors: Allen, David
• Granted Patent: US 7,344,275 B2
• Time in Patent Office: Days
• US Class Current: 362/227
• CPC Class Codes: F21S 4/10 with light sources attached to loose electric cables, e.g. Christmas tree lights
• CPC Class Codes: F21V 15/01 Housings, e.g. material or assembling of housing parts F21V15/02 takes precedence housings forming signs or letters G09F13/04
• CPC Class Codes: F21V 19/0005 of sources having contact pins, wires or blades, e.g. pinch sealed lamp F21V19/001 takes precedence
• CPC Class Codes: F21V 23/001 the elements being electrical wires or cables
• CPC Class Codes: F21V 31/005 Sealing arrangements therefor
• CPC Class Codes: F21V 31/04 Provision of filling media
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21W 2121/00 Use or application of lighting devices or systems for decorative purposes, not provided for in codes F21W2102/00 – F21W2107/00
• CPC Class Codes: F21W 2121/04 for Christmas trees
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/30107 Inductance
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05B 45/37 : Converter circuits
• CPC Class Codes: H05B 45/40 : Details of LED load circuits
• CPC Class Codes: H05B 45/42 : Antiparallel configurations
• CPC Class Codes: Y02B 20/30 : Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
• CPC Class Codes: Y10S 362/80 : Light emitting diode

Abstract

An LED light string employs a plurality of electrical components defined by LEDs and sockets wired in block series-parallel, where the one or more series blocks, each driven at the same input voltage as the source voltage (110 VAC or 220 VAC), are coupled in parallel. The LED light string interfaces to the source voltage using a common household plug; it may also include a corresponding common, household socket, coupled in electrical parallel, to enable multiple light strings to be connected to each other from end to end. In order to directly drive a network of diodes without current-limiting circuitry, the voltage of each series block of diodes must be matched to the input source voltage. This voltage matching requirement for direct AC drive places fundamental restrictions on the number of diodes on each diode series block, depending on the types of diodes used. For the voltage to be “matched,” it is possible to employ LED assemblies of different resistance values; e.g., the LED assemblies may emit different colors or be formed with a dedicated resistor (e.g., drop down resistor) integrally formed as part of at least one of the LED assemblies.

Claims

1. A light string comprising:

a predetermined number of light emitting diodes (LEDs) and sockets forming a plurality of individual electrical components electrically coupled in series to form at least one series block, each electrical component defining individual alternating current average drive voltages and individual resistance values, the series block having a first electrical component and a last electrical component, and

an alternating current electrical power supply having an average supply voltage,

wherein a summation of said individual alternating current average drive voltages is substantially equal to said average supply voltage, and wherein said individual resistance values vary among said plurality of individual electrical components.

2. The light string of claim 1, wherein said individual resistance values of at least two of said electrical components is substantially different because said at least two of said electrical components is adapted to emit a different color light.

3. The light string of claim 1, wherein said individual resistance values of at least two of said electrical components is substantially different because one of said at least two electrical components comprises a dedicated resistor integrally formed as part of said electrical component.

4. The light string of claim 1, wherein at least one of said electrical components comprises a dedicated resistor integrally formed as part of said electrical component.

5. The light string of claim 1, wherein said individual resistance values of at least three electrical components is substantially different from the remaining individual components.

6. The light string of claim 5, wherein said first electrical component is directly coupled intermediate a source end and a terminal end of a first set of wires and the last electrical component directly coupled intermediate the source end and the terminal end of a second set of wires, the light string being free from additional circuitry intermediate the first electrical component and the source end of the first set of wires, between each of the electrical components, and intermediate the last electrical component and the source end of the second set of wires, and

wherein a first connector is coupled to both the source end of the first set of wires and the source end of the second set of wires which connector facilitates a direct connection between the first electrical component and a first side of said alternating current electrical power supply, and the last electrical component and a second side of the alternating current electrical power supply.

7. The light string of claim 6, wherein said predetermined number of electrical components substantially equal to the supply voltage divided by an average of said individual alternating current drive voltages.

8. The light string of claim 1, wherein said individual alternating current drive voltages of said each electrical component is substantially the same.

9. The light string of claim 1, wherein said individual alternating current drive voltages of at least two of said electrical component is substantially different.

10. The light string of claim 1, further comprising rectification circuitry between said predetermined number of light emitting diodes and said power supply.