Abstract:
A settable light bulb whose brightness can be set by the user, and more particularly, to the use of a switch or a slide built in to the bulb itself to control the brightness in either discrete or continuous increments.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to light bulbs whose brightness can be set by the user, and more particularly, to the use of a switch or a slide, which is built in to the bulb to control the brightness in either discrete and/or continuous increments. 
       BACKGROUND OF THE INVENTION 
       [0002]    A light bulb typically comes with brightness preset by the factory. The brightness is typically proportional to the current through the light-emitting element or elements. The user of the bulb screws the bulb into an appropriately rated socket, and then the bulb may be set to be either on or off with a wall-mounted switch, with no intermediate choices. Three common technologies for the light bulb are incandescent, fluorescent and LED (light emitting diode). The most common is still the incandescent bulb, formed by surrounding a very hot filament in a partial vacuum with a glass shell. The fluorescent bulb is formed by surrounding a plasma column with a glass shell containing a phosphor, the phosphor serving to convert the ultraviolet radiation emitted by the plasma into visible light. Fluorescent bulbs which are designed to screw into conventional sockets are generically referred to as compact fluorescent lamps (or CFLs). Meanwhile, the LED bulb is formed by surrounding the LEDs with air or a fluid, gel or plastic, and encasing the LED inside a plastic shell. 
         [0003]    In some cases, bulb brightness may be continuously adjusted if the wall-mounted control unit includes a dimmer or dimmer switch. This works well for incandescent and LED light bulbs, and to some extent for fluorescent bulbs, if they have been specially designed to work with this type of control unit. Another method of controlling bulb brightness is the use of a 3-way socket, which permits discrete adjustment. Again, this works well with LED light bulbs and with 3-way incandescent bulbs, and with specially designed fluorescent bulbs. 
         [0004]    However, both dimmers and 3-ways require a specially-designed control unit. Most control units are simply on/off switches, and do not permit dimming or brightness-setting, even with bulbs that are designed for it. 
         [0005]    In many circumstances, it would be desirable to have the ability to control light bulb brightness without the presence of a specially designed control unit. A settable bulb would permit the dimming or selection of light output in the absence of a dimmer or 3-way controller. Another use would be when only a single type of bulb was available, but different brightness was desired in different locations. Accordingly, it would be desirable to a have a settable light bulb, which would permit multiple light level settings in a socket not configured for 3-way operation, and alleviate the problem of stocking multiple types of bulbs. 
       SUMMARY OF THE INVENTION 
       [0006]    This invention has the object of developing an apparatus with settable light output such that the above-described primary problem is effectively solved. In accordance with an embodiment, the apparatus with settable light output provides a light bulb whose light output may be either continuously or discretely set by the user, without requiring any special external control circuitry. The apparatus includes a light bulb, preferentially an LED light bulb, and includes either a slider control or a switch with at least two positions. The slider or switch controls either directly or indirectly, the current flowing in the light-emitting element or elements, thus controlling the brightness of the bulb. 
         [0007]    In accordance with one embodiment, a slider with a continuous range which is embedded in the body of the light bulb sets the current flowing in the light-emitting element or elements. In accordance with an embodiment, the slider can be a potentiometer feeding a signal proportional to the current back to a control circuit. The potentiometer can have a resistor in series, which sets the maximum current. 
         [0008]    In accordance with another embodiment, a switch with at least two discrete settings which is embedded in the body of the light bulb sets the current flowing in the light-emitting element or elements. The switch can select one of a number of discrete resistors feeding a signal proportional to the current back to a control circuit. 
         [0009]    In accordance with another embodiment, the slider or switch may control the frequency of oscillation of a circuit controlling a compact fluorescent lamp (or CFL). Control of the frequency controls the current flowing through the CFL, and thus the brightness of the CFL. 
         [0010]    In accordance with another embodiment, the switch controls which of at least two filaments is powered in an incandescent bulb. One setting of the switch turns on a first filament, a second setting turns on a second filament, and a third setting turns on both the first and the second filaments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
           [0012]      FIG. 1  is a cross-sectional view of a light bulb with a slider or switch embedded in its shell. 
           [0013]      FIG. 2  is a schematic of a circuit that utilizes a slider in the form of a potentiometer to continuously adjust the current, and thus the light output in an LED light bulb. 
           [0014]      FIG. 3  is a schematic of a circuit that utilizes a switch to set the current, and thus the light output in an LED light bulb to three predefined levels. 
           [0015]      FIG. 4  is a block diagram of a circuit that may utilize either a slider or switch to control the current through, and the brightness of a compact fluorescent lamp or CFL. 
           [0016]      FIG. 5  is a cross-section view of a compact fluorescent lamp or CFL with a slider or switch embedded in the base of the bulb. 
           [0017]      FIG. 6  is a cross-sectional view of a light bulb that utilizes a switch to control the number of filaments powered in an incandescent bulb. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0018]    Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. 
         [0019]    According to the design characteristics, a detailed description of the current practice and preferred embodiments is given below. 
         [0020]      FIG. 1  is a cross-sectional view of a light bulb  10  with a slider or switch  40  embedded in its shell  30 . As shown in  FIG. 1 , the light bulb  10  includes a screw-in base  20 , a plastic shell  30 , and a control mechanism  34  in the form of a slider or switch  40 . The screw-in base  20  includes a series of screw threads  22  and a base pin  24 . The screw-in base  20  is configured to fit within and make electrical contact with a standard electrical socket. The electrical socket is preferably dimensioned to receive an incandescent or other standard light bulb as known in the art. However, it can be appreciated that the screw-in base  20  can be modified to fit within any electrical socket which is configured to receive a light bulb, such as a bayonet style base. The screw-in base  20  makes electrical contact with the AC power in a socket through its screw threads  22  and its base pin  24 . The slider or switch  40  is embedded within the neck  32  of the shell  30 , although it can also be in some other portion of the shell  30 . In accordance with an alternative embodiment, the slider or switch  40  can be recessed within the neck  32  or raised above it, and preferably forms a seamless whole with said neck  32 . The slider or switch  40  has a control  44 . The control  44  is used to set the light output of the light bulb  10  in either a continuous range or a discrete range. 
         [0021]      FIG. 2  is a schematic of a circuit  100  that utilizes a slider  40  in the form of a potentiometer  42  to continuously adjust the current and thus the light output in an LED light bulb. In this schematic, input power  102  is supplied to the circuit  100  from a DC or AC rectified source, not shown. The input power  102  is fed to a string of at least one LED  70  in series, and this in turn has its current controlled by an inductor  80 . The actual current in said inductor  80  and said at least one LED  70  is set by the duty cycle of a switching transistor  60 . Increasing the duty cycle of said transistor  60  increases the current, while decreasing it decreases the current. During the off-time of said transistor  60 , the current in said inductor  80  and said at least one LED  70  is fed back to the input power  102  by a diode  90 . The current in transistor  60 , which is equal to the current in the inductor  80  and the at least one LED  70  during said transistor&#39;s  60  on-time, is measured by the potentiometer  42  and series limiting resistor  50 . The voltage  110  measured across said potentiometer  42  and the series limiting resistor  50  is used as feedback control to a regulator or control circuit, not shown, which controls the duty cycle of the transistor  60 . In accordance with an embodiment, the resistance of potentiometer  42  can be altered by setting a wiper  46 , which alters the voltage  110 . By altering the voltage  110 , the current through the at least one LED  70  is altered. In accordance with an exemplary embodiment, the potentiometer  42  sends a feedback signal to the regulator or control circuit, and wherein the feedback signal and corresponding voltage  110  is proportional to the current of the at least one LED  70 . 
         [0022]      FIG. 3  is a schematic of a circuit  100  that utilizes a switch  40  to set the current and thus the light output in an LED light bulb to three predefined levels. In this schematic, input power  102  is supplied to the circuit from a DC or AC rectified source, not shown. The input power  102  is fed to a string of at least one LED  70  in series, and this in turn has its current controlled by an inductor  80 . The actual current in said inductor  80  and said at least one LED  70  is set by the duty cycle of a switching transistor  60 . Increasing the duty cycle of said transistor  60  increases the current, while decreasing the duty cycle of the transistor  60  decreases the current. During the off-time of said transistor  60 , the current in said inductor  80  and said at least one LED  70  is fed back to the input power  102  by diode  90 . The current in the transistor  60 , which is equal to the current in the inductor  80  and the at least one LED  70  during the transistor&#39;s  60  on-time, is measured by one of the paralleled resistors  41 . The voltage  110  measured across one of the resistors  41  is used as feedback control to a regulator or control circuit, not shown, which controls the duty cycle of the transistor  60 . In accordance with an embodiment, selecting a different resistor from the paralleled resistors  41  by setting the switch  40  alters the voltage  110  and a corresponding feedback signal. By altering the feedback signal and the corresponding voltage  110 , the current through the at least one LED  70  is altered. In accordance with an exemplary embodiment, the switch  40  sends a feedback signal to the regulator or control circuit, and wherein the feedback signal and corresponding voltage  110  is proportional to the current of the at least one LED  70 . It can be appreciated that the circuit  100  can include more or less than three settings. It can be appreciated that in accordance with a preferred embodiment, the slider and/or switch  40  is preferably electrically isolated from other circuitry in the bulb  10 . 
         [0023]      FIG. 4  is a block diagram of a circuit  100  that utilizes either a slider or switch  40  to control the current through, and thus the brightness of a compact fluorescent lamp (CFL)  150 . The current through the CFL  150  is controlled by the value of the blocking capacitor  140  and the frequency of a power oscillator  120 . If the frequency of said oscillator  120  is controlled to be higher, the impedance of said capacitor  140  will be lower, and so the current through the CFL  150  will be higher; and similarly, if the frequency of said oscillator  120  is lower, the impedance of said capacitor  140  will be higher, and so the current through the CFL  150  will be lower. The frequency of the oscillator  120  is set by a control  130 . In turn, the signal to control  130  is set from the slider or switch  40 . The slider or switch  40  thus sets the current through the CFL  150 . 
         [0024]      FIG. 5  is a cross-section view of a compact fluorescent lamp or CFL  150  with a control mechanism  34  in the form slider or switch  40  embedded in a base portion  162  of the CFL bulb  150 . The CFL bulb  150  includes a plasma column  160  in the form of a tubular element  164 , which fluoresces when properly excited. For example, the tubular element  164  can be partially evacuated and filled with a gas or material. In accordance with an exemplary embodiment, the settable fluorescent light bulb or CFL  150  includes a fluorescent tube (or tubular element)  164  and a control mechanism  34  which is part of the bulb  150 . The control mechanism  34  sets a brightness of the bulb  150  by controlling the current through the plasma column  160 . The control mechanism  34  can be a slider or switch  40 . In accordance with an embodiment, the slider  40  is a potentiometer  42  ( FIG. 2 ) that sets a frequency of oscillation of a ballast running the fluorescent bulb  150 . Alternatively, the switch  40  controls at least one resistor that sets the frequency of oscillation of a ballast running the fluorescent bulb  150 . It can be appreciated that in accordance with a preferred embodiment, the slider and/or switch  40  is preferably electrically isolated from other circuitry in the bulb  150 . 
         [0025]    As shown in  FIG. 5 , the bulb  150  also includes a screw-in base  152 , which includes a series of screw threads  154  and a base pin  156 . The screw-in base  152  is configured to fit within and make electrical contact with a standard electrical socket. The electrical socket is preferably dimensioned to receive an incandescent or other standard light bulb as known in the art. However, it can be appreciated that the screw-in base  152  can be modified to fit within any electrical socket which is configured to receive a light bulb, such as a bayonet style base. The screw-in base  152  makes electrical contact with the AC power in a socket through its screw threads  154  and its base pin  156 . 
         [0026]      FIG. 6  is a cross-sectional view of a bulb  10  that utilizes a switch to control the number of filaments powered in an incandescent bulb  10 . As shown in  FIG. 6 , the light bulb  10  includes a screw-in base  20 , a plastic shell  30 , and a slider or switch  40 . The screw-in base  20  includes a series of screw threads  22  and a base pin  24 . The screw-in base  20  is configured to fit within and make electrical contact with a standard electrical socket. The electrical socket is preferably dimensioned to receive an incandescent or other standard light bulb as known in the art. However, it can be appreciated that the screw-in base  20  can be modified to fit within any electrical socket which is configured to receive a light bulb, such as a bayonet style base. The screw-in base  20  makes electrical contact with the AC power in a socket through its screw threads  22  and its base pin  24 . 
         [0027]    In accordance with an embodiment, the switch  40  is embedded within the neck  32  of the shell  30 , although it may also be in some other portion of the shell. Alternatively, in accordance with another embodiment, the switch  40  can be recessed within the neck  32  or raised above the neck  32 , and preferably forms a seamless whole with said neck  32 . In accordance with an embodiment, the switch  40  has a control  44 , with the control  44  having two states. In the first of the two states, AC power is applied to a first filament  160 . In the second of the two states, AC power is applied to a second filament  162 . Thus, the control  44  sets or determines which of the two filaments  160  or  162  are energized, and the brightness of the incandescent bulb  10 . In accordance with a further embodiment, it can be appreciated that arrangements with more than two settings can also be implemented using one or more controls  44 . In accordance with an exemplary embodiment, the switch  40  is electrically isolated from other circuitry in said bulb. In accordance with an exemplary embodiment, the switch  40  preferably has three settings, (i.e., a 3-way bulb), with settings corresponding to the power being applied to the first filament  160  (first setting), the second filament  162  (second setting), and both the first and the second filaments together (third setting). 
         [0028]    It will be apparent to those skilled in the art that various modifications and variation can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.