Abstract:
This invention includes a charger that may be mounted either in a horizontal configuration, e.g. on a desktop, or in a vertical configuration, e.g. on a wall. The charger has pockets geometrically oriented so as to support batteries in either configuration. Each pocket includes a corresponding display. As changing from a desktop configuration to a wall mount configuration requires the user to rotate the charger by 180 degrees, a switch is provided to rotate the information shown on the display by 180 degrees. The switch is preferably recessed below the surface of the charger so as to prevent nuisance actuation. The resulting orientation of the display is stored in a non-volatile memory to prevent resets when power is removed. By holding the switch down for a predetermined amount of time, a user can send the display into a test mode so as to run diagnostics and verify proper display operation.

Description:
BACKGROUND  
         [0001]    1. Technical Field  
           [0002]    This invention relates generally to battery chargers, and more specifically to battery chargers capable of being mounted both vertically and horizontally having displays.  
           [0003]    2. Background Art  
           [0004]    People today use electronic devices like pagers, personal digital assistants (PDAs), and cellular telephones all the time. These devices derive their portability from rechargeable batteries. Once a battery is fully charged, the accompanying device can be used without wires for several hours. When the stored energy in the battery is depleted, it must be recharged prior to further use.  
           [0005]    A very popular way of charging devices is by way of a desktop charger. An example of such a charger may be found in U.S. Pat. No. D427966, entitled “Two pocket desktop charger”, issued Jul. 7, 2000. This type of desktop charger may include two pockets: a first pocket for a device, like a cellular phone, with a battery coupled thereto; and a second pocket for a spare battery. In the case of a cellular phone, when the attached battery dies, the user simply inserts the phone/battery combination into the pocket and leaves it for a while. After some amount of time, generally 2-4 hours, the user removes the fully charged phone for use.  
           [0006]    Some desktop charger manufacturers have included displays and status indicators that notify the user when the battery is fully charged. These displays take on differing forms, including light emitting diodes (LEDs), liquid crystal displays (LCSs), and audible alarms. Examples of chargers having displays include U.S. Pat. Nos. 6,078,871, 5,726,555, and 4,396,881.  
           [0007]    For industrial users, single pocket chargers often prove to be inefficient. For example, police and fire departments often have several dozen radios in use. Using single pocket chargers is inefficient, as a very large desk space is required to accommodate such a large number of chargers. Further, as desk space becomes scarce, these users sometimes prefer to mount the chargers on the wall. Thus the “display-type” chargers in the aforementioned patents become cumbersome to use for two reasons: first the inefficiencies of the single pocket design, as noted above; and second due to the fact that wall mounted chargers must be precisely aligned so as to properly read the display.  
           [0008]    There is thus a need for an improved charger to accommodate industrial user needs. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is an isometric view of a charger in accordance with the invention.  
         [0010]    [0010]FIG. 2 is a sectional view of a charger in accordance with the invention with a small portion of the charger enlarged so as to see the reversible action of the display in accordance with the invention.  
         [0011]    [0011]FIG. 3 is a schematic block diagram of one preferred embodiment of a display controller in accordance with the invention.  
         [0012]    [0012]FIG. 4 is a schematic block diagram of another preferred embodiment of a display controller in accordance with the invention.  
         [0013]    [0013]FIG. 5 is a schematic block diagram of a charging circuit in accordance with the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0014]    A preferred embodiment of the invention is now described in detail. Referring to the drawings, like numbers indicate like parts throughout the views. As used in the description herein and throughout the claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise: the meaning of “a,” “an,” and “the” includes plural reference, the meaning of “in” includes “in” and “on.” 
         [0015]    Referring now to FIG. 1, illustrated therein is a charger  100  in accordance with the invention. The charger  100  is preferably manufactured from a durable, rigid injection molded plastic like a polycarbonate plastic. The charger  100  is generally a wedge shape so as to be mountable in both a horizontal configuration and a vertical configuration. The wedge is formed by way of an inclined plane  101  mounted on a base member  103 . The inclined plane  101  structure causes the front  105  to be shorter than the back  104 .  
         [0016]    The charger  100  includes a plurality of pockets, e.g.  106 ,  107 ,  108  for accommodating a plurality of batteries. Each pocket  106 - 108  is preferably at least half as deep as the battery to be charged. For example, if a battery measuring three inches in length is to be charged, the pockets  106 - 108  should be at least 1.5 inches in depth. Each pocket includes electrical contacts coupled to circuitry disposed in the charger. For example, pocket  106  includes electrical contacts  109 . The electrical contacts  109  deliver current regulated by the circuitry to the battery. The pockets preferably also include a spring-loaded mechanical lever  110  that deflects when a battery is inserted into the pocket  106 . This mechanical lever  110  may couple to a switch that actuates the circuitry associated with that pocket  106  upon battery insertion.  
         [0017]    The angle  102  formed between the inclined plane  101  and the base member  103  is critical to the “dual mountability” of the device. Acceptable angles  102  range from 30 to 60 degrees, but the angle is preferably 30 degrees. Viewing FIG. 1 with the “Horiz. Bottom” reference designator at the base, the inclined plane  101  causes batteries (which sit in the pockets  106 - 108  perpendicular to the inclined plane  101 ) to rest at an angle 60 degrees relative to the base member  103 , and thus the table or bench upon which the charger  100  sits. With pockets  106 - 108  having a depth at least half that of the batteries to be charged, even heavy batteries like the industrial nickel-metal hydride used by police departments rest comfortably in the pockets with no fear of falling out.  
         [0018]    Turning FIG. 1 so that the “Vert. Bottom” reference designator is at the base of the page, this orientation represents the “wall mount” configuration of the charger  100 . Metal-lined holes (not shown) in the bottom of the base member  103  provide the wall mount capability. In this orientation, the inclined plane forms an angle of 60 degrees with (what would be) the floor and the direction of gravitational pull. (60 degrees is the compliment of angle  102 .) Batteries inserted into the pockets  106 - 108  now rest at an angle of 30 degrees with the back  104 , which is now parallel to the ground. Again, with pockets  106 - 108  having a depth at least half that of the batteries to be charged, the batteries rest comfortably in the pockets with no fear of falling out.  
         [0019]    The charger  100  includes a plurality of light emitting diodes (LEDs), e.g.  111 ,  112 ,  113  associated with the respective pockets  106 - 108 . For example, LED  111  is associated with pocket  106 , and so on. The LEDs  111 - 113  serves as “quick look” charge status indicators. By way of example, if an LED  111  is red, this may indicate rapid charging. A flashing green LED may indicate top-off charging, and a solid green LED may indicate a fully charged battery. The LEDs  111 - 113  allow the user to glean a rough estimate of charging by glancing at the color.  
         [0020]    The charger  100  further includes a plurality of displays, e.g.  114 ,  115 ,  116 , associated with each pocket (similar to the LED association). The displays  114 - 116  are preferably low-power liquid crystal displays (LCDs). These displays  114 - 116  are driven by the charging circuitry disposed in the charger  100 . They are thus capable of displaying a plethora of specific charging information, including type of battery, serial number, manufacturing information, service information, status of charge, temperature, usage histograms, charge cycle counts, reconditioning information and the like.  
         [0021]    Each display  114 - 116  includes what appears to the user to be a hole  117 ,  118 ,  119 . The hole is actually an access opening to a switch disposed below the housing. Referring now to FIG.  2 , illustrated therein is the charger  100  having batteries  201 ,  202 ,  203  inserted therein. Dashed-line square  204  is a sectional view of one of the displays. Two embodiments of square  204  have been magnified in squares  205  and  206 . Square  205  illustrates an exemplary display  207  with charging text  208  illustrated thereon. Square  205  is an example of the “desktop” mode, in which the text is legible when viewed on a desktop.  
         [0022]    Square  206  illustrates an example of the “wall mount” mode. Note that a user holds a small tool  209  in his fingers  210 . The small tool  209  is used to access the push-button switch located below the charger housing  211 . The small tool  209  may be as simple as an ordinary paper clip, bent, so as to be inserted into the hole, or it may be a custom device with a cross section that matches that of the hole.  
         [0023]    When the small tool  209  is inserted, the orientation of the text rotates by 180 degrees. This is illustrated by example text  212 . By flipping the text  212 , the text now becomes legible to a user viewing the charger  100  in the wall mount configuration. Note that to keep the batteries properly oriented so as not to fall out, the display becomes rotated by  180  degrees when the charger is taken from a desktop configuration to a wall mount configuration. By depressing the switch, the text on the display rotates accordingly.  
         [0024]    The switch is preferably pressed only once. Once pressed, the circuitry stores the desired orientation in a non-volatile memory device. If the switch is pressed again, the text again rotates back to the original orientation. In other words, to change the orientation of the text, depress the switch once. The text will then stay in the new orientation, regardless of power failure due to the non-volatile memory, until it is depressed again.  
         [0025]    Referring now to FIG. 3, illustrated therein is a schematic block diagram in accordance with the invention. The circuit of FIG. 3 is illustrative of the circuitry associated with a single pocket, and would be replicated for the number of pockets in the charger. The circuit includes a microprocessor  300  having at least one digital input  301 . The switch  302  is coupled to the input  301  and transitions states by way of a pull-up resistor  303 . When the switch is depressed, the input  301  changes from Vcc  309  to ground  310 . The microprocessor  300  then stores this information into a non-volatile memory device, preferably an electrically erasable, programmable, read only memory (EEPROM)  305 . By writing to an EEPROM  305 , the microprocessor  300  is able to recall the last desired orientation regardless of any power outages that might occur. Note that flash memory devices could be substituted for the EEPROM.  
         [0026]    The microprocessor  300  then sends the orientation information to the LCD controller  304 . Examples of suitable LCD controllers include the S6A0093 manufactured by Samsung. The microprocessor  300  sends refresh data to the LCD controller  304  causing it to refresh in reverse, thereby inverting the image on the display. In addition to communicating with the LCD controller  304 , the microprocessor  300  also controls charging circuitry  307  coupled to a power source  306 , as well as the LEDs  308 .  
         [0027]    Note that the circuit of FIG. 3 includes a “dual function” microprocessor  300 , in that the microprocessor  300  controls both the LCD controller  304  and the charging circuitry  307 . In multi-pocket applications, it is often advantageous to separate the control of the charging circuitry and the data/display functions. This separation provides the designer with the ability to customize the features of the pocket without interfering with the charging circuitry. For example, if one wants a high-power microprocessor for diagnostics, yet a low-power microprocessor to control charging, this can be accomplished by separating the charging circuitry and the data/display circuitry.  
         [0028]    Referring now to FIG. 4, illustrated therein is the display circuitry, which has been separated from the charging circuitry. A microprocessor  400  receives battery data from charging circuitry (shown in FIG. 5) through a data terminal  402 . The circuit receives power from a power  401  and a return  403  terminals, both coming from the charging circuitry. As in FIG. 3, a switch  405  actuates the rotation of the text. The microprocessor  400  stores the text orientation in the EEPROM  405 . The microprocessor  400  further controls the LCD driver  404 .  
         [0029]    Referring now to FIG. 5, illustrated therein is a general charging circuit that may be applied to charge a battery  501  placed in the pocket of the charger. A microprocessor  500  (which is distinct from the microprocessor of FIG. 4) receives data from the battery  501  by way of a data terminal  502 . This microprocessor  500  controls charging current by way of a current regulator  505  coupled to the power supply  504 . Note that the LEDs (shown as, e.g.  111  in FIG. 1) are shown as  503 , and are controlled by the microprocessor  500 .  
         [0030]    While the preferred embodiments of the invention have been illustrated and described, it is clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions, and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as defined by the following claims. For example, the microprocessor  300  may be programmed to provide additional features. When the button is pressed for a predetermined period of time, for instance, the display might enter a test mode. In the test mode, the display cycles through a series of data, thereby allowing the user to evaluate display functionality. Such data may include all pixels on, all pixels off, checkerboard pixel pattern, text right-side up, and text upside down. To exit this test mode, the button is pressed again.