Abstract:
The present invention achieves the above objects, among others, by providing, in a preferred embodiment, a transformer system for use with either a dimmer switch or an on/off switch, including: a transformer; a load connected to the transformer; a first tap connected to the transformer to provide a first voltage; and a second tap connected to the transformer to provide a second voltage higher than the first voltage. A method of using the transformer system is also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   The present application claims the benefit of the filing date of U.S. Provisional Application Ser. No. 60/462,500, filed Apr. 11, 2003, and titled TRANSFORMER FOR DIMMER SWITCH OR ON/OFF SWITCH AND METHOD OF USE. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to transformers generally and, more particularly, but not by way of limitation, to a novel transformer for use with a dimmer switch or an on/off switch and a method of use thereof. 
   2. Background Art 
   A conventional transformer for lighting systems can be used with either a dimmer switch or an on/off switch. A disadvantage of such an arrangement is that when the transformer is used with a dimmer switch, the voltage applied to the lighting system at full input is less than when the same transformer is used with an on/off switch in “ON” position. The result is that the light level output of the lighting system at full output of the dimmer switch is substantially less than that when the transformer is used with an on/off switch in “ON” position. 
   Accordingly, it is a principal object of the present invention to provide a transformer and method that can be used with either a dimmer switch or an on/off switch and wherein the light level at full output of the lighting system with which the transformer is used is approximately the same with either a dimmer switch or an on/off switch. 
   A further object of the invention is to provide such a transformer that is economical to construct. 
   An additional object of the invention is to provide such a method that can be easily implemented. 
   Other objects of the present invention, as well as particular features, elements, and advantages thereof, will be elucidated in, or be apparent from, the following description and the accompanying drawing figures. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     Understanding of the present invention and the various aspects thereof will be facilitated by reference to the accompanying drawing figures, provided for purposes of illustration only and not intended to define the scope of the invention, on which: 
       FIG. 1  is a graph of percentage light output vs. lamp voltage. 
       FIG. 2  is schematic of a transformer, with primary side taps, and with a dimmer switch installed in the primary circuit thereof. 
       FIG. 3  is a schematic of the transformer of  FIG. 1 , with primary side taps, and with an on/off switch installed in the primary circuit thereof. 
       FIG. 4  is a schematic of a transformer, with secondary side taps, and with a dimmer switch installed in the primary circuit thereof. 
       FIG. 5  is a schematic of the transformer of  FIG. 3 , with secondary side taps, and with an on/off switch installed in the primary circuit thereof. 
   

   SUMMARY OF THE INVENTION 
   The present invention achieves the above objects, among others, by providing, in a preferred embodiment, a transformer system for use with either a dimmer switch or an on/off switch, comprising: a transformer; a load connected to said transformer; a first tap connected to said transformer to provide a first voltage; and a second tap connected to said transformer to provide a second voltage higher than said first voltage. A method using said transformer system is also provided. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference should now be made to the drawing figures on which similar or identical elements are given consistent identifying numerals throughout the various figures thereof, and on which parenthetical references to figure numbers, when used, direct the reader to the view(s) on which the element(s) being described is (are) best seen, although the element(s) may be seen on other figures also. 
     FIG. 1  illustrates the dramatic drop-off in light output as lamp voltage is decreased. Although the light outputs and voltages shown on  FIG. 1  are for a nominal 12-volt lamp, provided for illustrative purposes only and not intended to limit the scope of the present invention, the decrease in light output is similar for lamps of other voltages. The output voltage of a lighting industry standard 12-volt transformer is about 11.4 volts at about 120-volt input, giving a light output of about 85 percent of 12 volts when an on/off switch is used, a reasonable level. However, when a dimmer switch is used, the maximum output voltage is about 10.6 when the dimmer switch is at full bright, giving a light output of about 64 percent of rated light output at 12 volts. Thus, a decrease in voltage of about 12 percent from 12-volts has resulted in a light output decrease of about 36 percent of maximum—an undesirable result, which the present invention addresses. It will be understood that the present invention compensates for the loss introduced by a dimmer switch. 
     FIG. 2  illustrates a transformer system, constructed according to the present invention, and generally indicated by the reference numeral  10 . Transformer system includes a transformer  12  having a primary winding  20  with two primary side taps, TAP-1 and TAP-2, and with a dimmer switch  30  connected to TAP-2. The secondary circuit includes a secondary winding  40  and a “LOAD”  50  which may be assumed to be a lighting system. 
     FIG. 3  illustrates transformer system  10  with an on/off switch  60  connected to TAP-1. 
   According to the invention, the connections of side taps TAP-1 and TAP-2 to primary winding  20  are selected such that the secondary voltage is higher when dimmer switch  30  is used ( FIG. 2 ) than when an on/off switch  60  is used ( FIG. 3 ), the higher voltage in the first case compensating for the reduction in voltage when dimmer switch  30  is used. Therefore, the same transformer can be used in either case to produce approximately the same lighting level from load  50  regardless of whether dimmer switch  30  is used or on/off switch  60  is used, the voltage compensation being provided when dimmer switch  30  is connected to TAP-2 rather than TAP-1. 
     FIG. 4  illustrates a transformer system, constructed according to the present invention, and generally indicated by the reference numeral  100 . Transformer system  100  includes a transformer  112  having a primary winding  120  that has a dimmer switch  130  connected thereto. Transformer  100  also includes a secondary winding having two secondary side taps TAP-1 and TAP-2. In this case, the load  150 , which may be assumed to be a lighting system is connected to TAP-2. 
     FIG. 5  illustrates transformer system  100  with an on/off switch  160  connected to primary winding  120 . In this case, load  150  is connected to TAP-1. 
   It will be understood, with reference to  FIGS. 4 and 5 , that TAP-2 is at a higher voltage than TAP-1, the difference compensating for the voltage loss in dimmer switch  130  ( FIG. 2 ), such that the full lighting level of load  150  with dimmer switch  130  is the same as with on/off switch  160  ( FIG. 5 ) in “ON” position. 
   In either case, the unused tap, TAP-1 or TAP-2, is simply ignored. Thus, the same transformer can be used for either the dimmer switch situation or the on/off switch situation, while providing the same maximum output lighting level from each. 
   Although  FIGS. 2–5  show toroidal transformers, the present invention is applicable as well to other types of conventional transformers, such as laminated and electronic transformers, the toroidal transformers being shown for illustrative purposes only and are not intended to limit the scope of the invention. 
   In the embodiments of the present invention described above, it will be recognized that individual elements and/or features thereof are not necessarily limited to a particular embodiment but, where applicable, are interchangeable and can be used in any selected embodiment even though such may not be specifically shown. 
   Spatially orienting terms such as “above”, “below”, “upper”, “lower”, “inner”, “outer”, “inwardly”, “outwardly”, “vertical”, “horizontal”, and the like, when used herein, refer to the positions of the respective elements shown on the accompanying drawing figures and the present invention is not necessarily limited to such positions. 
   It will thus be seen that the objects set forth above, among those elucidated in, or made apparent from, the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown on the accompanying drawing figures shall be interpreted as illustrative only and not in a limiting sense. 
   It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.