BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a horizontally-oriented decorative light display with incandescent light source assemblies displayed.
FIG. 1A is a perspective view of a vertically-oriented decorative light display with incandescent light source assemblies displayed.
FIG. 2 is a side view of the decorative light display.
FIG. 3 is a front view of the decorative light display mounted to a shelf.
FIG. 4 is an electrical circuit diagram of the decorative light display with incandescent light source assemblies.
FIG. 5 is a perspective view of the decorative light display with LED light source assemblies displayed.
FIG. 6 is an electrical circuit diagram of the decorative light display using LED light source assemblies.
FIG. 7 is a perspective view of the decorative light display with both LED light source assemblies and incandescent light source assemblies displayed.
DETAILED DESCRIPTION OF THE DRAWINGS
One embodiment of the decorative light display of the present invention is shown generally in FIG. 1. Decorative light display 10 includes an enclosure 12 with a front panel 11, plurality of light source groups 14, one or more power supplies 18, and power cord 20. Light source group 14 includes a plurality of light source assemblies 16 and decorative light display 10 may include any number of light source groups 14. In one embodiment, enclosure 12 and panel 11 are constructed of cardboard material and may include printed graphics and other printed information relevant to a potential light string buyer. Although in this embodiment the enclosure shape is generally depicted as rectangular and including front panel 11, those skilled-in-the-art will appreciate that the enclosure may be of any shape and configuration such that the light source assemblies are viewable in the enclosure.
While the embodiment shown in FIG. 1 illustrates light display 10 as a horizontally-oriented light display, light display 10 may alternatively be a vertically-oriented light display as illustrated in FIG. 1A.
Light source assemblies 16 may be incandescent light source assemblies 15 as shown in FIG. 2, LED light source assemblies 38 as shown in FIG. 5, or other light source assemblies such as electroluminescent light source assemblies. Light source assemblies 15 and 38 include base portions 19a and 19b, and bulb assembly portions 17a and 17b, respectively. The bulb assembly portions 17a, b may utilize bulbs or covers made from glass, plastic or other materials in a variety of shapes and sizes. In one embodiment, all incandescent light source assemblies 15 operate on approximately the same voltage, and all LED light source assemblies 38 operate on approximately the same voltage. The operating voltage of incandescent light source assemblies 15 may differ from the operating voltage of LED light source assemblies 38. In other embodiments, the operating voltages and currents may vary from light group to light group within a single display 10.
In one embodiment, power supply 18 is an LVLE power supply, such as a Class 2 power supply or an ITE power supply, that reduces a 120 VAC source voltage to a lower voltage such as 12 VAC. Using a LVLE power supply isolates the higher source voltage from light source groups 14 and limits available energy, thereby reducing the risk of shock and fire. In other embodiments, power supply 18 may consist of other types of power supplies that reduce the source voltage, including those that output DC power, where DC power includes constant voltage DC, battery-sourced DC power, and full-wave or half-wave rectified AC power.
FIG. 2 shows a side view of one embodiment of decorative light display 10. Light source groups 14 are inserted through panel 11 such that much of light source assemblies 15 protrude through panel 11 and are visible when decorative light display 10 is viewed from the front. In other embodiments, light source assemblies 15 may be configured such that they do not protrude through panel 11, yet remain viewable within light display 10. Light source group wire set 28 consists of several wires 21 leading into light source group 14. Light source groups 14 are interconnected with interconnection wire set 30. Interconnection wire set 30 may consist of wires that are of greater length than the wires 21 of light source group wire sets 28. Making the wires 21 of light source group wire sets 28 relatively short in relation to the wire lengths of interconnection wire set 30 reduces the overall cost and weight of decorative light string display 10 and increases the ease of assembly of display 10.
As shown in FIG. 2, display 10 also includes shelf connector 22. In one embodiment, shelf connector assembly 22 includes an adhesive-backed plate 26 that adheres to enclosure 12 and receives connector 24. Connector 24 may consist of any number of connectors including a nylon wire tie, a wire, string, or other type of connector that allows display 10 to be connected to a supporting structure, such as shelf 32, as shown in FIG. 3. In other embodiments, shelf connector assembly 22 may include self-tapping screws or other fasteners, may connect light display 10 to more than one shelf 32, and may not include adhesive-backed plate 26. In yet another embodiment, light display 10 may be a free-standing light display, and therefore not be connected to shelf 32 and not include shelf connector assembly 22.
FIG. 4 is an electrical circuit diagram of display 10 where light source groups 14 include only incandescent light assemblies 15. In this embodiment, power supply 18 is an LVLE power supply that reduces incoming 120 VAC source voltage to 12 VAC. Although a typical decorative light string consists of incandescent bulbs connected in series blocks, often with thirty-five or more incandescent bulbs, the incandescent light assemblies 15 of this embodiment of the present invention are connected in parallel and operate on 12 VAC. In some embodiments, power supply 18 may supply a voltage less than or greater than 12 VAC to accommodate incandescent light assemblies 15 that require other operating voltages. By connecting incandescent light source assemblies 15 in parallel, if one incandescent light source assembly 15 fails, the other light source assemblies 15 in display 10 will remain lit, unlike a typical series-connected decorative light string.
Another advantage of the parallel construction is that all light source assemblies 15 operate on the same voltage, allowing interchangeability of assemblies 15 in the event of a failure of any one of the light source assemblies 15. This means that light source assemblies 15 with different appearances, e.g., different colors and shapes, are actually interchangeable. For example, a pearl-shaped light assembly may be connected in parallel with a cylindrical traditional mini-bulb. This interchangeability of light assemblies 15 differs from the actual decorative light strings being sold. Typically, the operating voltage characteristics of prior art light source assemblies in a decorative light string of one shape bulb and bulb count differs from the operating voltage characteristic of light assemblies using a different shape bulb and bulb count. Using the previous example, a traditional pearl-shaped light assembly used in a decorative light string operates on 3.5V, whereas a traditional mini-bulb light assembly in a string with 50 or 100 light assemblies connected in series will operate on 2.5V, preventing interchangeability of light source assemblies.
In another embodiment, incandescent light assemblies 15 are connected in series-parallel, rather than a purely parallel connection. In the series-parallel embodiment, the failure of any one incandescent light assemblies 15 will interrupt current to the other light assemblies 15 in the series block, causing all the light assemblies 15 in the block to fail. For this reason, the number of light assemblies 15 employed in a single series block is minimized. For example, a series-parallel embodiment of the present invention may include five incandescent light assemblies 15 per series block.
In the embodiment shown in FIG. 5, decorative light display 10 includes enclosure 12, light source groups 14, LED light source assemblies 38, power supply 34 and power cord 36. In this embodiment, display 10 uses LED light source assemblies 38 instead of incandescent light source assemblies 15 of the previously discussed embodiment. The number of LED light source assemblies 38 may be varied according to space requirements, desired lighting effect, and other requirements. Power supply 34 receives power from an external source voltage and supplies the appropriate power and voltage to LED assemblies 38.
FIG. 6 is an electrical circuit diagram of display 10 where light source groups 14 include only LED assemblies 38. In the embodiment shown in FIG. 6, power supply 34 is connected to a 120 VAC source. Power supply 34 is typically an LVLE power supply, such as a Class 2 power supply, that reduces source voltage to a lower AC or DC voltage. In this embodiment, power supply 34 reduces the 120 VAC source voltage to 6 VDC, and includes a transformer 46 and rectifier 48. In other embodiments, power supply 34 could supply other DC voltages to LED assemblies 38, and may provide half-wave, full-wave, or other rectification of the incoming source voltage, and may or not include capacitors. In the embodiment shown in FIG. 6, the conversion from AC to DC takes place in an externally located power supply, however, in other embodiments, the conversion from AC to DC could occur within enclosure 12.
In the embodiment of FIG. 6A, power supply 34 does not include internal rectification. In this embodiment, rectification circuitry, for example rectifier 48, is located within light display 10, external to power supply 34.
As also shown in FIGS. 6 and 6A, each LED assembly 38 includes an LED 45 and may include a resistor 44. Resistor 44 may be located in either the base portion 19b, the bulb portion 17b, or in the wire (not shown). The value of the resistor is selected to drop the voltage supplied by power supply 34 to the operating voltage and current required by LED 45. The operating voltages and currents of LEDs 45 typically vary by color and manufacturer. In the embodiments illustrated in FIGS. 6 and 6A, LED's 45a require different operating voltages than LEDs 45b and 45c. As such, resistors 44a vary in value or magnitude from resistors 44b and 44c. The ability to vary the resistor values of resistors 44 allows the display of many kinds of LEDs 45 in light display 10 while using a single power supply 34. In this embodiment, all LED assemblies 38 are wired in parallel. However, in an alternate embodiment, LED assemblies 38 may also be wired in series-parallel blocks, similar to the way that the incandescent light assemblies 15 discussed above were alternatively wired in series-parallel blocks.
FIG. 7 is a perspective view of a decorative light string display 10 that utilizes both LED light source assemblies 38 and incandescent light source assemblies 15. In this embodiment, power supply 34 and power cord 36 provide the appropriate AC or DC power to LED assemblies 38, while power supply 18 and power cord 20 supply the appropriate AC or DC power to incandescent light assemblies 15.
The invention may be embodied in other specific forms without departing from the spirit of the essential attributes thereof. Therefore, the illustrated embodiments should be considered in all respects as illustrative and not restrictive.