Patent Document

BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    One or more embodiments of the present invention generally relate to a battery powered vanity mirror and light assembly having a regulator circuit therein for use in a vehicle. 
         [0003]    2. Background Art 
         [0004]    Lithium batteries are generally used for powering light emitting diodes (LEDs) in a power vanity lighting mirror. For example, such batteries may provide up to three volts to power the LEDs. The voltage may decrease to two volts the longer the battery is switched on. During periods of cold weather, the voltage output from the battery may be between two and three volts, such voltage levels may adversely affect the illumination of the LEDs. 
         [0005]    It is generally recognized that LEDs are powered with a voltage of between 2.8 and 3.6 volts. Such an input voltage requirement varies from LED to LED. The light intensity of the LEDs may vary based on the amount of voltage used to power the LEDs within the mirror. 
       SUMMARY 
       [0006]    A visor vanity including a visor body for a vehicle having an electrical system is provided. A visor vanity including a visor body for a vehicle having an electrical system is provided. The visor body includes a visor mirror, at least one light source, a switch, a regulator circuit and a timer. The switch causes at least one energy source that is independent of the electrical system of the vehicle to generate a first voltage signal. The regulator circuit is operably coupled to the switch and to the energy source for transmitting a second voltage signal in response to the first voltage signal so that the light source receives the second voltage signal. The timer is powered by the energy source for causing the regulator circuit to disable the operation of transmitting the second voltage signal in response to the timer achieving a predetermined count value. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view of a visor assembly; 
           [0008]      FIG. 1   a  is a partial section view of the visor taken along the line  1   a - 1   a  of  FIG. 1 ; 
           [0009]      FIG. 2  is a perspective view of a visor assembly; 
           [0010]      FIG. 3  is a perspective view of the rear of an assembled vanity mirror light assembly; 
           [0011]      FIG. 4  is an exploded view showing a first embodiment of the vanity mirror light assembly of  FIG. 3 ; 
           [0012]      FIG. 5  is an exploded view showing an alternative embodiment of the vanity mirror light assembly to that shown in  FIG. 3 ; 
           [0013]      FIG. 6   a  is a schematic of an example embodiment of a circuit for vanity mirror light assembly; 
           [0014]      FIG. 6   b  is a schematic of an example alternative embodiment of a circuit for the vanity mirror light assembly; 
           [0015]      FIG. 6   c  is a schematic of an example embodiment of a regulator circuit in accordance to one embodiment of the present invention; 
           [0016]      FIG. 6   d  is a schematic of an example alternative embodiment of a regulator circuit in accordance to one embodiment of the present invention; 
           [0017]      FIG. 6   e  is a schematic of an another example of embodiment of a circuit in accordance to one embodiment of the present invention; and 
           [0018]      FIG. 7  is a diagram depicting a method for regulating voltage across a light emitting diode (LED) of the vanity mirror light assembly. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Referring to  FIG. 1 , a visor assembly  100  includes a visor  200  and a visor arm  300  having a visor bracket  302  of a conventional design. 
         [0020]    The visor arm  300  is typically mounted to the visor bracket  302  which in turn may be mounted to any suitable mounting surface, such as the sheet metal of the vehicle roof (not shown). The visor arm  300  is typically pivotally connected to the visor bracket  302  such that the visor arm  300  together with the visor  200  may be moved into desired positions. For example, the visor arm  300  may typically be pivoted at the visor bracket  302  such that the visor  200  may be moved into positions such as adjacent to the front or side windows of a vehicle. Such brackets and pivotal connections are well known in the art and will not be described in further detail here. 
         [0021]    The visor  200  is preferably mounted to the visor arm  300  via a torque control such that the visor  200  may be rotated relative to the visor arm  300 . Such a torque control is preferably mounted within the visor  200  for aesthetic reasons. Any suitable type of torque control or other mechanism can be used that allows the visor  200  to be moved between, and held in, various rotational positions with respect to the visor arm  300 . This allows the visor  200  to be moved between a lowered substantially vertical position or to a raised position which is substantially horizontal or higher. Such torque control arrangements are well known in the prior art and will not be described in further detail here. 
         [0022]    As shown in  FIGS. 1-4 , in the visor embodiments shown, the visor  200  includes a visor body  202 . The visor body  202  includes a vanity mirror light assembly  400 . The vanity mirror light assembly  400  includes a vanity bezel  410 , a cover  430  hingeably connected to the vanity bezel  410 , a light source assembly  440 , a switch  450 , a timer  460 , an energy source  470 , and a circuit board  480 . 
         [0023]    The visor body  202  may be substantially solid or hollow and may include a substrate formed from plastic, foam, press board, or any other desired material. Any suitable visor body configuration or construction may be used with this invention. The visor body  202  in this particular embodiment is formed of a one-piece clamshell construction having a front body portion  204  and a rear body portion  206 . The exterior surface  208  of the front body portion  204  and rear body portion  206  may be covered by a suitable covering  210 , such as fabric, cloth, vinyl, leather, or any other suitable material or combination of materials. The front body portion  204  and rear body portion  206  may be connected by a live hinge  212  along one side. 
         [0024]    The visor body  202  may also include a fastening mechanism such as body snaps to assist in the assembly of such a visor body  202  having a clamshell construction. Such body snaps may be of any suitable configuration such as the locking pin and socket snaps disclosed in U.S. Pat. No. 5,054,839 issued on Oct. 8, 1991 to White et al. Such snaps may have sockets or female snap receptors  216  situated at appropriate locations along the interior surface  218  of the rear body portion  206  and locking pins or male snap protrusions  220  situated at appropriate locations along the interior surface  218  of the front body portion  204  such that the male snap protrusions  220  are adjacent to, and will engage and lock into the female snap receptors  216  when the clam shell visor body  202  is closed. The interlocking of the female snap receptors  216  and male snap protrusions  220  will not only maintain such a clam shell visor body  202  in a closed position, such arrangement also serves to add structural rigidity to the visor body  202  when assembled. As shown in this embodiment, such female snap receptors  216  and male snap protrusions  220  may be integrally molded into the visor body  202  as a one-piece construction. Also, any other suitable mechanism for connecting a front body portion to a rear body portion could be used. In such a construction, or in any other suitable hollow visor body construction, the hollow space within the visor body  202  may be referred to as the visor body inner space  222 . 
         [0025]    As shown in  FIGS. 1 ,  1   a , and  3 , the front body portion  204  may include a body recess  224  and one or more body apertures  226  which can be of any suitable size and configuration and which are in communication with the visor body inner space  222  such that the vanity mirror light assembly  400  to be housed within the visor body  202  may be utilized. As shown in  FIGS. 1 and 1   a , in this embodiment the body recess  224  is dimensioned to receive the vanity mirror/light assembly  400  in an aesthetically pleasing manner. 
         [0026]    More specifically, in the embodiment shown in  FIGS. 3 and 4 , the vanity mirror/light assembly includes a bezel  410  having heat stake protrusions  412  located along the bezel interior surface  414  while the front body portion  204  of the visor body  202  includes heat stake apertures  228 . During assembly of the visor assembly  202  of this embodiment, and before the front body portion  204  is folded over and connected to the rear body portion  206  of the visor body  202 , the complete mirror/light assembly  400  is placed within the body recess  224  such that the heat stake protrusions  412  are inserted into and through the heat stake apertures  228 . Then the heat staking process takes place during which the ends of the heat stake protrusions  412  are deformed such that the vanity mirror/light assembly is locked into place within the body recess  224  of the front body portion  204  of the visor body  202 . 
         [0027]    As shown in  FIG. 1 , the bezel  410  of the vanity mirror/light assembly  400  may have a mirror opening  416  of any suitable configuration. As shown in  FIGS. 1 and 4 , a mirror  428  may be mounted to the bezel interior surface  414  in any suitable manner such that the reflective surface  429  of the mirror  428  is exposed at the mirror opening  416  of the bezel  410  and available for use by a user of the vanity/mirror light assembly  400 . The mirror  428  may attached to the bezel  410  in any suitable manner. Such attachment methods are known in the art. In the embodiment shown, the mirror  428  is mounted to the bezel interior surface  414  by heat staking  415 . 
         [0028]    As shown in  FIG. 4 , the bezel  410  of this embodiment also includes a bezel light recess  418  and bezel light recess aperture  419 . A light source assembly  440  including a light source  442  and light source mount  444  may be positioned upon assembly such that the light source  442  is located within the light recess  418 . The light source  442  can be any desired light source, such as a light emitting diode (LED) or incandescent light bulb. In the case of an incandescent bulb, or wherever else desired, the light source mount could include a socket such that the light source  442  could be removed and replaced if desired. LEDs are preferred because they use less energy, thereby extending the useful life of the independent energy source, such as a battery. In the embodiments shown in  FIGS. 1 and 4 , one LED bulb  446  has been used. However, any number of bulbs having any desired characteristics may be utilized. 
         [0029]    In the embodiments shown in  FIGS. 1 ,  4 ,  6   a , and  6   b , the bulb  446  is operatively mounted within the light source mount  444  which may have electrodes such that it can be operatively connected to the electrical circuit  482 . The light source mounts  444  may be mounted such that the light source  442  is positioned within the light recess  418  in any suitable manner. For example, as shown in the embodiment of  FIGS. 1 and 4 , the light mount  444  may be mounted to the circuit board  480  in any suitable manner, such as by heat staking, snaps, or soldering for example. The latter might be especially appropriate if the light source mount  444  had electrical leads which could be operatively soldered into the circuit  482  of the circuit board  480 . As another alternative, the leads to the light source  442  could be operatively soldered into the circuit  482  of the circuit board  480  without using any light source mount. Such mountings are well known in the art and will not be discussed in further detail here. Further, the light source may be operatively located and mounted in any other suitable location in any suitable manner, including by heat staking, soldering, or otherwise, such as to or within the vanity body, vanity bezel, or circuit board. Such mountings are well known in the art and will not be discussed in further detail here. 
         [0030]    A lens  490  may be provided for diffusing the light from the light source  442  and can be attached to the visor body  202  or vanity bezel  210  in any suitable or desired manner. In the embodiment shown in  FIGS. 1 and 4 , the lens  490  is designed so as to be snap fitted within a light/lens opening of the bezel  410  so as to cover the underlying light source  442 . Because such snap fittings or other suitable attachment methods are well known in the art, they will not be discussed in further detail here. 
         [0031]    The cover  430  may be connected to the bezel  410  in any suitable manner such that the cover  430  may be moved from a covering to an uncovering position and vice versa. In the embodiment shown, the cover  430  is connected to the bezel  410  by way of a cam and spring hinge  432  arrangement such that the cover  430  will tend to remain in a fully covering or fully uncovering position. Such arrangements are well known in the art and will not be described in further detail here. Furthermore, while the cover  430  in these embodiments is shown to be hingeably connected to the bezel, such a cover could be hingeably connected to the visor body  202  as well. While the cover  430  is shown in these embodiments as being hingeably mounted, such a cover  430  could also be mounted so as to move in a sliding, pivoting, or any other suitable manner so as to cover and uncover the mirror as desired. 
         [0032]    The energy source  470  of this invention is independent of the vehicle&#39;s electrical system. The energy source  470  can be any desired independent source of energy, such as one or more batteries  472 . In such case, any appropriate number and capacity of batteries could be used. In the embodiment shown in  FIGS. 1 and 4 , the energy source  470  may comprise three 1.5V batteries in series. Any suitable batteries may be used, such as lithium type batteries. As shown in this embodiment, the batteries  472  may be attached to the circuit board  480 . Such attachment can be made in any suitable manner, such as by using standard mounts for such batteries, such as battery mount clips having electrodes such that they can be operatively connected to the electric circuit  482  (e.g., see  FIGS. 6   a  and  6   b ). Such attachment mechanisms are well known in the art and will not be discussed in further detail here. Note that while the energy source  470  of this embodiment is shown to be mounted to the circuit board  480 , the energy source may be mounted in any suitable manner and location, such as to or within the vanity assembly, including the vanity body  202  or vanity bezel  410 . For example, while not shown, the energy source could be mounted within a compartment of the vanity or visor body, with such compartment having a removable covering such that the batteries or other such independent energy source  470  could be replaced when desired. 
         [0033]    Alternatively, the energy source could be mounted within a compartment of the bezel, with such compartment having a removable covering such that the batteries or other such independent energy source  470  could be removed and replaced when desired. One possible embodiment of such an arrangement is shown in  FIGS. 1 and 5 , which show the use of two batteries  472  attached to the circuit board  480  such that when the vanity mirror/light assembly  400  is assembled, the batteries  472  are located within the bezel recess  418  on either side of the light source  442  under the lens  490 . Such attachment of the batteries  472  to the circuit board  480  can be made in any suitable manner, such as by using standard mounts for such batteries, such as battery mount clips having electrodes such that they can be operatively connected to the electric circuit  482  (e.g., see  FIGS. 6   a  and  6   b ). Such attachment mechanisms are well known in the art and will not be discussed in further detail here. In this embodiment, the lens  490  can be attached to the vanity bezel  210  in any suitable or desired manner such that it is removable so that the batteries can be removed and replaced when desired. For example, in the embodiment shown in  FIGS. 1 and 5 , the lens  490  may be designed so as to be snap fitted within the light/lens opening  424  of the bezel  410  so as to cover the underlying light source  442  and batteries  472 . This would allow the light source  442  as well as the batteries  472  to be replaced when desired. Because such snap fittings or other suitable attachment methods are well known in the art, they will not be discussed in further detail here. 
         [0034]    In the event a single battery  472  is implemented (e.g., 3 volt battery), the size of the entire circuit board  480  may be reduced over that shown so that the circuit board  480  is not positioned behind the mirror  428 . Specifically, in such an implementation, the entire circuit board  480  may be positioned about the bezel light recess  418  and the light recess aperture  419  with no such portion of the circuit board  419  extending into a position behind the mirror  428 . 
         [0035]    In any of the embodiments, the switch  450  can have any desired configuration or can be of any desired mechanism, so long as it serves to close the circuit when the cover  430  is in an open position, such that the light source  442  is energized, and to open the circuit when the cover  430  is in a closed position, such that the light source  442  is de-energized. Any such switch used may include electrodes such that it can be operatively connected to the electrical circuit  482  (e.g., see  FIGS. 6   a  and  6   b ). In the embodiment shown, the light switch  450  is a plunger switch  452  having a plunger  454  which extends through a plunger aperture  420  of the bezel  410  and beyond the bezel front face  422  such that it will be plunged or released when the cover  430  is closed or opened respectively. In the event the cover  430  is mounted so as to slide or pivot as opposed to being hinged, alternative switch arrangements, which are known in the art, may be used. In fact, even in the event the cover is hingeably connected, switches other than a plunger switch  452  may be utilized. The switch  450  may be mounted to the visor body  202 , the bezel  410 , the circuit board  480 , or on any other suitable location and by any suitable method. The plunger switch  452  may be attached in the appropriate location to the bezel  410  by heat staking or through any other suitable mounting method. In the embodiment shown in  FIG. 4 , the bezel  410  is mounted to the circuit board  480  such that when the circuit board  480  is assembled with the bezel  410 , the plunger switch  452  is in the appropriate location such that the plunger  454  extends through the plunger aperture  420  of the bezel  410 . In such case, any suitable mounting method may be used. Because such mounting methods are well known in the art, they will not be discussed in further detail here. 
         [0036]    The visor assembly  100  also includes a timer  460  which serves to de-energize the light source  442  after a certain time period. Such timer may have electrodes such that it can be operatively connected to the electrical circuit  482  (e.g., see  FIGS. 6   a  and  6   b ). More specifically, for example, if the cover  430  is inadvertently left in an open position, the light source  442  will be de-energized after a predetermined amount of time so as to conserve or reduce usage of the energy source  420 . This prevents the energy source  420 , such as batteries, from being inadvertently depleted. Such a timer  460  would reset if the switch  450  were again activated by the closing and opening of the cover  430  or otherwise. The timer  460  could be a separate component interconnected with the electrical circuit  482  so as to provide the desired affect. While any suitable timer  460  could be used, the timer  460  could also be incorporated as a component of the switch  450 . For example, a plunger switch  452  incorporating a timer  460  would be suitable. Such a timer could be operatively mounted to the visor body  202 , the bezel  210 , the circuit board  480 , or on any other suitable location and by any suitable mounting method. For example, the leads of such a timer  460  could be operatively soldered into the circuit  482  of the circuit board  480 . Because such mounting methods are well known in the art, they will not be discussed in further detail here. 
         [0037]    The circuit board  480  may be of any suitable configuration and may include any desired electrical components and an electrical circuit  482  (e.g., see  FIGS. 6   a  and  6   b ). Any circuit  482  may be configured to include the energy source  420 , switch  450 , timer  460 , and light source  442  (e.g., LED  446 ) such that, when the cover  430  is opened and the switch  450  is closed, the light source  442  will be energized; such that when the cover  430  is closed and the switch  450  is opened, the light source  442  will be de-energized; and such that, if the cover  430  is opened for a certain period of time the timer  460  will operate to de-energize the light source, thereby conserving the life of both the energy source  420  and the light source  442 . 
         [0038]    Furthermore, while not shown in these embodiments, the visor assembly  100  could include a switch operated by the user of the vanity mirror instead of the cover  430 . Alternatively, the visor assembly  100  could include a user switch such that if it were desired to energize the light source  442  for a length of time beyond that of the timer  460 , the user could engage such a user switch to do so. Such switch alternatives could be operatively part of the electric circuit  482  and any such user switches could be located at the bezel front face  422 . 
         [0039]      FIG. 2  discloses another one of many possible alternative embodiments of the invention. In this embodiment as shown, in lieu of a light source assembly  440  underlying a lens  490  within a bezel light recess  418 , the bezel includes LED openings  427  through which two LEDs  447  protrude. No lens is required. The LEDs may be mounted to the circuit board or to the bezel in any suitable manner. Of course, and light source other than LEDs could also be used. In the event LEDs are used, any appropriate LEDs may be used. Two 3 mm yellowish white LED bulbs having a forward voltage between 2.8 and 4.0V may be suitable. However, any number of bulbs having any desired characteristics may be utilized. 
         [0040]      FIG. 6   a  is a simplified schematic of one of many possible circuits  482  which may be used when the timer  460  is incorporated as a component of the switch  450  such as described above. The circuit could include other components as desired. The switch could be a cover activated switch, a user activated switch, or otherwise. Other elements of the circuit  482  in this sample embodiment are the LED  446 , a resistor  449 , and the battery energy source  472 . 
         [0041]      FIG. 6   b  shows a simplified schematic of an alternative possible circuit  482  with a timer  460  in the form of a switch being a separate component from the light switch  450 . Again, the light switch could be a cover activated switch, a user activated switch, or otherwise. 
         [0042]      FIG. 6   c  is a schematic of an example embodiment of a circuit  500  in accordance to one embodiment of the present invention. The circuit  500  may be used as an alternative circuit in place of the circuits depicted in  FIGS. 6   a  and  6   b . The circuit  500  comprises the LED  446 , the switch  450 , the battery energy source  472 , a regulator circuit  502 , a resistor  504 , and a timer  506 . In general, the battery energy source  472  is generally capable of providing up to three volts for powering the LED  446 . The LED  446  on the other hand generally needs a supply voltage within a predefined voltage range of 3.0 to 3.5 volts to illuminate. To compensate for the possible 0.5 voltage shortfall from what the battery energy source  472  is capable of providing, the regulator circuit  502  may increase the amount of voltage provided to the LED  446 . In one example, the regulator circuit  502  may be the ZXSC400 boost circuit as produced by Zetex Semiconductors®. 
         [0043]    In operation, as the user opens the cover  430  to the open position, the switch  450  closes thereby allowing the battery energy source  472  to provide voltage to power the regulator circuit  502 . The regulator circuit  502  generally requires an input voltage of between one and eight volts. The regulator circuit  502  provides an output voltage for powering the LED  446  in response to the voltage provided by the battery energy source  472 . The resistor  504  is positioned in series with the LED  446 . The regulator circuit  502  measures voltage across the resistor  504  and uses such a measured voltage as feedback for determining whether the LED  446  is receiving a voltage within the predefined voltage range of between 3.0 to 3.5 volts. 
         [0044]    For example, the regulator circuit  502  generally includes a predetermined voltage value stored therein that corresponds to a predetermined voltage drop across the resistor  504 . The predetermined voltage drop across the resistor  504  is indicative of the amount of current flowing through the LED  446 . In one example, the predetermined voltage value may correspond to a value of approximately 0.3 volts. The predetermined voltage value may vary accordingly based on the size of the resistor and on the particular current requirements of the LED  446  that is needed to allow the LED  446  to illuminate as desired. The regulator circuit  502  compares the measured voltage across the resistor  504  to the predetermined voltage value to determine the amount of current to provide to the LED  446 . 
         [0045]    The regulator circuit  502  is generally configured to provide the same amount or more voltage than that is capable of being provided by the battery energy source  472 . The regulator circuit  502  is generally configured to hold the current constant across the LED  446  by continually monitoring and comparing the voltage across the resistor  504  to the predetermined voltage value and adjusting the voltage output in response thereto. While not shown, it is generally contemplated that additional LEDs may be added to the circuit  500  so that such additional LEDs may receive the same voltage output from the regulator circuit  500 . By ensuring that the LED  446  and any additional LEDs positioned within the vanity mirror and light assembly receives a constant current, the LED  446  and the additional LEDs (not shown) may provide a similar light output from one another through all voltage variations. 
         [0046]    The timer  506  is generally enabled to begin a count sequence in response to the switch  450  being closed. The timer  506  may be set to open the circuit  500  upon achieving a predetermined count value. In one example, the predetermined count value may correspond to 90 seconds. The length of the predetermined count value may affect the life of the battery energy source  472 . As such, a larger predetermined count value may adversely impact the life span of the battery energy source  472 . In most cases, automotive Original Equipment Manufactures (OEMs) may require that the life span of the battery energy source  472  achieve a ten year life span. Due to such a requirement, it is generally contemplated that the predetermined count value may correspond to a value between 30 to 240 sec. The timer  506  may be implemented as Part Number MC14541B as produced by ON Semiconductor®. In response to the timer  506  achieving the predetermined count value, the timer  506  may transmit a control signal to the regulator circuit  502  so that the regulator circuit  502  may discontinue providing voltage to the LED  446 . 
         [0047]      FIG. 6   d  is a schematic of an example alternative embodiment of the circuit  500  in accordance to one embodiment of the present invention. Circuit  500 ′ includes a plurality of battery energy sources  472 ′ coupled in a parallel configuration. Multiple battery energy sources  472 ′ may be implemented in order to achieve the OEM desired life span. For example, the battery energy source  472  as noted in connection with  FIG. 6   c  may provide 550 mAh. The plurality of battery energy sources  472 ′ as depicted in circuit  500 ′ may provide for 1100 mAh and a total voltage output of 3.0 volts. In such a case, the regulator circuit  502  may increase the amount of voltage that is provided by the plurality of energy sources  472 ′ to provide the desired amount of voltage to the LED  446 . 
         [0048]      FIG. 6   e  is a schematic of an example alternative embodiment of the circuit  500  in accordance to one embodiment of the present invention. Circuit  500 ″ resembles that of circuit  500 ′ with the exception of the plurality of battery energy sources  472 ′ being shown in a series configuration. Such a battery arrangement may also achieve the OEM desired life span. Each energy source  472 ′ may provide up to 1.5 volts. The battery energy sources  472 ′ as depicted in  FIG. 6   e  may provide a total of 4.5 volts. As such, the regulator circuit  502  may be configured to reduce the amount of voltage provided to the LED  446  from the battery energy sources  472 ′. As noted above, the regulator circuit  502  generally requires an input voltage of between one and eight volts. In the event the regulator circuit  502  receives 4.5 volts from the battery energy sources  472 ′, the regulator circuit  502  may step down the voltage and transmit the desired voltage to drive the LED  446  to achieve the desired illumination. The regulator circuit  502  may measure the voltage across the resistor  504  and compare the measured voltage across the resistor  504  to the predetermined voltage value to ensure that the current delivered to the LED  446  is at the desired level. 
         [0049]    As the voltage generating capabilities of the battery energy sources  472 ′ decrease over time, the regulator circuit  502  may step up or boost the voltage provided to the LED  446 . For example, in the event the plurality of battery energy sources  472 ′ provide a voltage of 3 volts or less to the regulator circuit  502 , the regulator circuit  502  may provide a voltage output that is higher than the 3 volts to power the LED  446  in the event such an increase in voltage is needed to achieve the desired illumination. In one example, the regulator circuit  502  that is capable of either boosting input voltage or decreasing input voltage may be the TPS61130, TPS61131, or TPS61132 buck/boost DC/DC converter circuit as produced by Texas Instruments®. It is generally contemplated that the regulator circuits as discussed in connection with  FIGS. 6   c - 6   d  may also be implemented as a buck/boost DC/DC converter. The timer  506  may operate in the same manner as described in connection with  FIG. 6   c.    
         [0050]    The battery energy source  472  as noted in connection with  FIG. 6   c  and the plurality of battery energy sources  472 ′ as noted in connection with  FIGS. 6   d - 6   e  are independent from the vehicle&#39;s electrical system and are generally lithium batteries. In one example, each battery energy source  472  and  472 ′ may be implemented as a CR2450HR battery. 
         [0051]      FIG. 7  is a diagram depicting a method  600  for regulating energy across the LED  446  of the vanity mirror light assembly. 
         [0052]    In operation  602 , a user opens the cover  430  to the open position, the switch  450  closes allowing the battery energy source(s)  472  (and/or  472 ′) to power the regulator circuit  502 . 
         [0053]    In operation  604 , the timer  506  begins counting in response to the switch  450  closing. 
         [0054]    In operation  606 , the regulator circuit  502  receives voltage from the battery energy source  472  (or plurality of battery energy sources  472 ′) and transmits an output voltage to the LED  446 . 
         [0055]    In operation  608 , the regulator circuit  502  measures the voltage drop the resistor  504  to assess whether the output voltage needs to be adjusted. 
         [0056]    In operation  610 , the regulator circuit  502  compares the measured voltage drop across the resistor  504  to the predetermined voltage value. If the measured voltage drop is less than the predetermined voltage value, then the method  600  moves to operation  612 . If the measured voltage drop is greater than the predetermined voltage value, then the method  600  moves to operation  614 . 
         [0057]    In operation  612 , the timer  506  determines whether the count sequence has expired. If the count sequence has expired, then the method  600  moves to operation  616 . If the count sequence has not expired, then the method  600  moves to operation  606 . In operation  606 , the regulator circuit  502  increases the amount of voltage delivered to the LED  446 . 
         [0058]    In operation  614 , the timer  506  determines whether the count sequence has expired. If the count sequence has expired, then the method  600  moves to operation  616 . If the count sequence has not expired, then the method  600  moves to operation  606 . In operation  606 , the regulator circuit  502  decreases the amount of voltage delivered to the LED  446 . 
         [0059]    In operation  616 , the timer  506  transmits the control signal to the regulator circuit  502  so that the regulator circuit  502  discontinues providing voltage (or current) to the LED  446 . 
         [0060]    While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.

Technology Category: 5