Portable battery charger for cellular telephones

[0001] This patent application claims the benefit of the filing date of U.S. Provisional Patent Application Serial No. 60/347,232, filed Jan. 8, 2002 and entitled CELLULAR TELEPHONE BATTERY CHARGER, the entire contents of which is hereby expressly incorporated by reference.

[0002] The present invention relates generally solar battery charging devices and more particular to a compact portable solar/battery powered cellular telephone battery charging device.

[0003] Most cellular phones are equipped with rechargeable batteries which can be recharged through an adapter used in conjunction with household alternating current (AC) power or through an adapter used in conjunction with a 12-volt cigarette lighter outer provided in an automobile. However, depending on the frequency or duration of use of the cellular phone, leaving the phone in the ON mode or engaging in air time talking to another person, the battery may only last for a few hours.

[0004] It would be desirable to have a portable battery charging device that is capable of using solar power to charge batteries in a cellular phone.

[0005] It would also be desirable to have a battery charging device that is capable of charging the battery in a cellular phone through the power of regular non-rechargeable batteries.

[0006] It would further be desirable to have a cellular phone battery charging device that uses solar power to charge one or more self contained rechargeable batteries for use as backup batteries and that permits use of such backup batteries to charge the battery in the cellular phone or to power the cellular phone directly.

[0007] It is therefore an object of the present invention to provide a convenient portable device for charging cellular phone batteries so that the phone is always available for communications usage.

[0008] It is another object of the present invention to provide a cellular phone battery-charging device that utilizes solar power as its energy source. It is yet another object of the invention to provide a device to charge cellular phone batteries from a set of rechargeable batteries not originally equipped with the cellular phone.

[0009] Briefly, a presently preferred embodiment of the present invention is comprised of three basic component parts including two separate solar panels and a battery and switch containing unit. The two panels are hingedly connected together, and the internal battery and switch containing unit is hingedly connected to the back side of one of the panels. The assembly is pivotable between a retracted configuration in which the three component parts lie in parallel planes, and a deployed configuration in which the two solar panels lie in one plane and the battery/switch unit lies in another plane angularly intersecting the solar panel plane. The device is selectively operable in three different modes; namely a first mode in which the solar panels are connected to charge or power a phone coupled to the device, a second mode in which the solar panels are connected to charge the internal battery, and a third mode in which the internal battery is used to charge or power a phone coupled to the device.

[0010] An important advantage of the present invention is that it provides a portable means for charging the battery of a cellular phone or other battery powered device without requiring connection to residential or commercial power source.

[0011] Another advantage of the present invention is that it provides a device of the type described that can be used to charge or power a phone with or without ambient sunlight.

[0012] Still another advantage of the present invention is that it provides a device of the type described that in the presence of sunlight can recharge its own internal batteries.

[0013] These and other objects and advantages of the present invention will no doubt become apparent to those skilled in the art after having read the following detailed description of the embodiment illustrated in the several figures of the drawing.

[0014] FIG. 1 is a generalized block diagram schematically illustrating the principal components of an exemplary cellular phone battery charging device in accordance with the present invention;

[0015] FIG. 2 is a generalized diagram schematically illustrating the battery charger of FIG. 1 and its various operational modes;

[0016] FIGS. 3A-3C are schematic diagrams depicting the three operational modes alluded to in FIG. 2;

[0017] FIGS. 4A-4D are diagrams illustrating various types of adapter cables that may be used to interface the battery charging device of the present invention to common types of cellular phone devices;

[0018] FIG. 5 is a frontal perspective view illustrating an embodiment of the present invention in its retracted configuration;

[0019] FIG. 6 is a perspective view illustrating the embodiment of FIG. 5 with one of its solar panels deployed; and

[0020] FIG. 7 is a perspective view illustrating the embodiment of FIG. 5 in its fully deployed configuration with its battery and switch containing component pivoted outwardly.

[0021] Referring now to the drawing, FIG. 1 is a block diagram schematically illustrating an exemplary cellular phone battery charging device in accordance with the present invention. The device 10 includes a solar panel 12, a battery charger 14, and an adapter cable 16 for providing power to and/or charging the battery 18 in a cellular phone 20.

[0022] The battery charger 14 is suitably electrically connected to the solar panel 12 for receiving electrical power converted from solar energy by the solar panel. The technology of converting solar energy to electrical power is well known to one skill in the art.

[0023] The adapter cable 16 has on one end a first plug (not shown) for connection to a receptacle 22 in the batter charger 14, and a second plug (not shown) on the other end for connection to a connector 24 on the cellular phone 20. The second plug of the adapter cable 16 can be of any of many interface configurations suitable for connection to cellular phones manufactured by different companies. For instance, it could be made to adapt to cellular phones manufactured by vendors, such as Qualcomm, Nokia, Motorola, Samsung, Toshiba, Erisson, etc. The cellular phone user may select from several provided configurations the adapter cable suitable for his particular cellular phone interface. The adapter cable 16 is normally attached to the cellular phone 20 during the time of charging the cellular phone battery, but may be disconnected upon completion of the charging process. One may also talk on the cellular phone during the charging operation.

[0024] FIG. 2 is a block diagram schematically illustrating the battery charger 14 and its mode selection switch 26. As illustrated, the battery charger 14 includes a housing 28 adapted to receive four AA-sized batteries arranged so that they are connected in series. These batteries can be regular non-rechargeable AA-sized batteries or may be rechargeable batteries of similar capacity. However, rechargeable type batteries must be used if they are to be recharged. Either regular non-rechargeable batteries or rechargeable batteries can be used to charge the battery 18 in the cellular phone 20.

[0025] The switch 26 is use to select the operational mode, that is, the source and destination of the charging operation to be performed. In the illustrated embodiment, and as indicated by a dashed arrow 30, the switch can be positioned to select one of three positions. Placing the switch in a first position 32 connects the output of the solar panel directly to an output connector 16 (FIG. 1) so that the converted solar power can be used to charge the cellular phone battery. Placing the switch in a second position 34 directs the power from the batteries in the charger 14 to the output connector connected to the cellular phone, either to be directly consumed by the cellular phone or to be used to charge the battery in the cellular phone. Positioning the switch in a third position 36 connects the output of the solar panel directly to the batteries installed in the battery housing to chage them.

[0026] The charger 14 further includes a plurality of LEDs indicating the charging operation selected by the switch position. A first LED 38 relates to the first switch position 32, and is turned on when the switch is placed in this position to charge the cellular phone directly using the converted solar power. A second LED 40 relates to the second switch position 34, and is turned on when the storage batteries installed in the housing 28 of the charger are used to charge the cellular phone.

[0027] FIGS. 3A-3C are schematic circuit diagrams depicting circuit connections in the three switch selectable modes alluded to in the discussion of FIG. 2. In these FIGS. the operative circuits are signified by bold lines, and the switch contacts connected to the terminals L1-L4 and R1-R4 are labeled 50-64. The contact bridging member is denoted by a dashed box labeled 27a-27c in the respective FIGS., 3A-3C.

[0028] Note that the energy developed by the solar cells in the solar panel 12 is used in the switched modes of FIGS. 3A and 3B, but not in that of FIG. 3C wherein an internal battery is used as a source of power.

[0029] The positive terminal 44 of solar panel 12 is coupled through a first diode 48 to an external terminal L2 of the switch 26. An external terminal L1 is connected to one side of a jack 22, and an external terminal R1 is connected to a circuit common node 49 via a first LED 38 and its associated load resister. Terminal R1 is also shorted to a terminal R3, with R2 and R4 being left open. Terminal L3 is connected to the positive terminal of an internal battery 66, the negative side of which is connected to common node 49. Terminal L4 is connected via a diode 39 to the top side of jack 22, and via a second LED 40 and its associated load resister to the common node 49.

[0030] In the first switch position 32 (FIG. 2), as illustrated by the dashed box 27a in FIG. 3A, the L-shaped contacting element of a contact bridging member connects terminals L1, L2 and R1 in common so that luminous energy received by the panel 12 (as suggested by the rays 42) and converted into electrical power having a positive polarity at a terminal 44 and a negative polarity at a terminal 46, is connected through a diode 48 and switch 26 to jack 22. This is to say that with the switch 26 in the first position as described above, the converted solar power is sent to the output jack, connector or receptacle 22 to feed through an adapter cable 16 to a battery in a cellular phone or the like. In this switch position, the first LED 38 is connected across the jack 22 and thus turned ON to confirm the connection.

[0031] When the contact bridging member is placed in the mid-position 36, as described above with respect to FIG. 2, L2 is connected to R2 and L3. In this position, no LED is turned on because the contact bridging member does not contact R1, R3 or L4, the terminals leading to the LEDs. In this position, solar panel 12 is connected directly across the internal battery 66 and, as a result, the solar power flows into and charges the batteries if they are rechargeable.

[0032] When the contact bridging member is moved to the position 34, as described above, and as indicated in FIG. 3C by the dashed box 27c, the terminals L3 and L4 are connected to terminal R3. With the switch in this configuration, battery 66 is connected directly across the jack 22 as well as both LEDs 38 and 40. Accordingly both LEDs are lit to indicate that a phone connected thereto is being powered, or is having its batteries charged, by the internal battery or batteries 66 of the charger unit 14.

[0033] In the exemplary embodiment, four AA, 1.5 volt batteries contained within the device housing are coupled together in series to deliver as much as 6 volts in potential across the terminals of jack 22. Since most cellular phones are powered by 4.8 volts or 3.6 volts, or even as low as 2.4 volts, to charge the battery in the cellular phone through the set of regular batteries installed in the charger, the potential must be reduced to the appropriate potential before the device is connected to the battery in the cellular phone. This can be accomplished by a selection circuit (not shown) provided in the device 14, or by a suitable voltage dropping circuit included within one of the connectors associated with the adaptor cables 16.

[0034] One advantage of this configuration is that regular batteries can be installed in the housing to charge the cellular phone battery. Furthermore, in case of emergency where no other chargers are available and where the environment has insufficient light to actuate the solar panel 12, regular batteries may be used to power the cellular phone through this arrangement. Similarly by using one or more re-chargeable batteries in the device, and taking care to see that the batteries are periodically charged using the solar panel, one can always be assured of having battery backup power.

[0035] FIGS. 4A-4D are diagrams showing various configurations 16A-16D of adapter cables used to interface the battery charging device of the present invention to various types of cellular phones. FIG. 4A depicts an adapter cable for interfacing the battery charging device of the present invention to batteries in Nokia cellular phones. FIG. 4B depicts an adapter cable suitable for interfacing the charging device to batteries in cellular phones having a SIM interface. FIG. 4C illustrates an adapter cable for interfacing the device to batteries in Motorola cellular phones, and FIG. 4D shows an adapter cable for interfacing the device to batteries in Ericson cellular phones.

[0036] Turning now to FIGS. 5-7, an actual embodiment of the present invention is illustrated and includes a two piece solar panel 12 pivotally affixed to a battery and switch housing 14 by a suitable hinge mechanism 15. As more clearly shown in FIG. 6, housing 14 carries the switch 26 internally and includes a rectangular opening through which a manually engageable slider affixed to the contact bridging member 27 extends. In addition, circular openings are provided through which the LEDs 38 and 40 are visible. Molded, embossed or otherwise applied above the LEDs and switch are labels identifying the three switch positions/operational modes.

[0037] FIG. 6 also reveals the two part solar panel and the hinge structure 70 used to hingedly attach the two panels 12A and 12B that make up the panel assembly 12. Although not shown in detail, the hinge structure 70 is comprised of elongated front and back plates that capture top and bottom pivot pins that are positioned within notched portions of the panels and extend towards each other. The plates are secured to each other by three bolts 72. Hinge structure thus allows the two panels to rotate between a retracted position, as shown in FIG. 5, aligned with and facing each other, and a deployed position lying in side-by-side adjacent relationship, as depicted in FIG. 6.

[0038] FIG. 6 also shows the slideable cover labeled OPEN behind which four AA size regular or re-chargeable batteries are contained. In addition, a small opening 74 is shown on the right side of housing 14. Beneath this opening is this jack 22 (FIGS. 3A-3C) for receiving the adapter cable used to connect the device to a cell phone or other electrically powered device.

[0039] FIG. 7 shows the device in its solar energy collecting configuration with the panels 12A and 12B in their deployed configuration, and also illustrates how the housing 14 can be rotated approximately 90 degrees outwardly relative to the panels to provide a means for supporting the panels so that they lie in a plane intersecting at about 45 degrees the surface upon which they rest. Note that in this disposition the solar energy responsive faces of the panels face generally upwardly and if faced in a southerly direction will gather maximum sunlight during most of the day.

[0040] In the foregoing specification, the invention has been described with reference to a specific embodiment thereof. It will, however, be evident that various changes and substitutions of parts may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are accordingly to be regarded in an illustrative rather than a restrictive sense.

[0041] Furthermore, although the present invention has been described in terms of an embodiment having particular design features, it is anticipated that other alterations and modifications may become apparent to those skilled in the art after having read the above disclosure. It is therefore intended that such disclosure be considered illustrative and not limiting, and that the appended claims be interpreted to include all such alterations, designs, modifications and embodiments as fall within the true spirit and scope of the invention.