This invention relates to a charger for a portable battery powered device and a mobile phone case. In particular, this invention relates to a charger for a mobile phone.
Portable handheld devices, such as mobile phones, cameras and media players, are powered by batteries, which carry a finite amount of charge. Over recent years there has been a continual drive to reduce the size and weight of these devices. At the same time, the functionality of these devices has increased and hand-in-hand with this increase in functionality has been an increase in the power consumption of these devices. This is particularly the case for mobile phone handsets, and particularly smart phones, whose capabilities have become more akin to that of personal computers. Consequently, one of the problems which many users of smart phones encounter is the need to balance the use of the phone with a limited battery capacity, and this can often lead to the batteries of such handsets losing their charge to the extent that the handsets no longer function.
The present invention provides a solution to this problem.
According to a first aspect of the invention there is provided a charger for a portable battery powered device, the charger comprising: a mobile phone case body for receiving a mobile phone, the body comprising means for removably receiving and holding one or more batteries; contacts for engaging with terminals of the or each battery; a circuit housed within the body and coupled to at least a pair of the contacts, the circuit being configured to convert a voltage of the battery or batteries into a predetermined charging voltage; and a connector extendable from the body for providing the charging voltage to a said portable battery powered device. According to a second aspect of the invention there is provided a mobile phone case comprising: a body for receiving a mobile phone, the body comprising means for removably receiving and holding one or more batteries; contacts for engaging with terminals of the or each battery; a circuit housed within the body and coupled to at least a pair of the contacts, the circuit being configured to convert a voltage of the battery or batteries into a predetermined charging voltage; and a connector extendable from the body for providing the charging voltage to a said portable battery powered device. According to a further aspect of the invention there is provided a charger for a portable battery powered device, the charger comprising a generally planar body, the body comprising means for removably receiving and holding one or more batteries; contacts for engaging with terminals of the or each battery; a circuit housed within the body and coupled to at least a pair of the contacts, the circuit being configured to convert a voltage of the battery or batteries into a predetermined charging voltage; and a connector extending from the body for providing the charging voltage to a said portable battery powered device, wherein major dimensions of the charger are less than 86 mm by 54 mm and a thickness of the charger is less than 5 mm. The means for removably receiving the one or more batteries may comprise one or more aperture or cut-out. When the battery or batteries are received in the charger or case, portions of the battery extend beyond planar external faces of a wall in which the aperture or cut-out are disposed. The or each aperture may have opposed longitudinal walls comprising the means for holding the battery.
The means for holding the battery may comprises a strip or discrete portions of compressible material mounted along at least part of one or both of the opposed longitudinal walls.
The means for a holding the battery may be a partially or fully split strip or a U-shaped strip. The means for holding the battery may be made of rubber.
A separation between edges of the means for holding the battery may be less than a diameter or thickness of a said battery.
The body may comprises: a frame defining a cavity for receiving the said one or more batteries; a PCB tray mounted to an end of the frame for holding the circuit; and a circuit cover. Alternatively, the frame and PCB tray may be formed as a single part. The or each battery may be cylindrical.
In use, an axis of the or each battery may lie in the same plane as the body.
The or each battery may be an AA, a AAA or a C-type battery or another type of battery.
The charger or case may be adapted to receive and hold two batteries.
The portable battery powered device may be a mobile phone, i.e., the charger may be a mobile phone charger.
According to a further aspect of the invention there is provided a charger for a portable battery powered device, the charger being adapted to be arranged in a first, stowed configuration and in a second, deployed configuration, wherein: in the first configuration the charger is substantially flat; and in the second configuration the charger is adapted to hold and electrically couple with one or two batteries, the or each battery having a height greater than its diameter or width.
In the stowed configuration the major dimensions of the charger may be less than 86 mm by 54 mm.
The charger or case may further comprise an electrical connector for connection to said portable battery powered apparatus. According to a further aspect of the invention there is provided a mobile phone charger which is adapted to receive and electrically couple with two AA type batteries and which has major dimensions of less than 86 mm by 54 mm and a thickness of less than 5 mm. The thickness may preferably be less than 4 mm. The thickness may preferably be less than 3 mm.
According to a further aspect of the invention there is provided a battery powered mobile phone charger which is dimensioned such that it is insertable into a credit card slot of a wallet or purse and when inserted into the credit card slot less than 20% of the overall volume of the charger protrudes from the slot.
According to a further aspect of the invention there is provided a charger for a portable battery powered apparatus, the charger comprising: a body having two apertures, each aperture: being adapted to removably receive a cylindrical battery; having electrical contacts at its ends; and being lined at least partially along its longitudinal edges with compressible material for holding said battery in the aperture, a DC-DC converter circuit housed within the body and coupled to a pair of the contacts; and a device connector extending from the body and coupled to the output of the DC-DC converter circuit.
The charger or case may further comprise a rechargeable power cell for providing charge when no battery is received in the charger. The rechargeable power cell may be a rechargeable battery. The charger or case may further comprise means for connecting the charger to a USB power source.
According to a further aspect of the invention there is provided a kit of parts comprising: a charger or case as described above and one or more battery.
The kit of parts may further comprise a mobile phone.
According to a further aspect of the invention there is provided a case for a mobile phone, the case comprising means for receiving a charger as described above. The means for receiving a charger may be an aperture in the case.
When the charger is disposed in the aperture in the case the charger may substantially close the aperture to form a wall of the case.
The means for receiving the charger may substantially corresponds to the shape of the charger to provide a push-fit or compression fit arrangement to hold the charger in the case.
The charger or case described above is powered by batteries, such as AA or AAA batteries. The alternative to using this charger to charge portable devices is to use a mains powered device to charge the portable device. Such a mains powered device may be a dedicated charger, such as a charger for a mobile phone, a USB (RTM) port of a computer or a USB socket found in some dual power/USB mains sockets. Since these devices typically use transformers to transform mains (210/240 V rms AC) to 5 V DC, they are very inefficient. Conversely, since the present device merely transforms 3 V DC to 5 V DC then it is more efficient than mains powered portable device transformers. In addition, since rechargeable batteries can be used to power the charger of the present invention, and since there are widely available solar powered battery chargers, the present invention can be used to charge portable devices, such as mobile phones, without needing to use the main power supply whatsoever. Both of these advantages of the present invention provide environmentally friendly solutions to charging portable devices, such as mobile phones.
The invention will be further described by way of example with reference to the accompanying drawings in which:
Each aperture 104a, 104b is rectangular and has overall major dimensions similar to those of a cylindrical battery. In the present embodiment each aperture 104a, 104b has overall major dimensions similar to those of an AA type battery. Sprung contacts/terminals 110a, 110b are provided at opposed ends 112a, 112b of each aperture 104a, 104b. The contacts are sprung to allow for variations in the length of the cylindrical batteries within the limits of their standard dimensions. The contacts 110a, 110b are made of an electrically conductive metal such as aluminium, copper or steel. The contacts 110a, 110b are made of a thin spring metal material which is folded so as to be compressible against ends of the battery.
Each aperture 104a, 104b and its associated contacts 110a, 110b are dimensioned to provide a snug compression fit for an AA type battery, such that when an AA type battery is inserted into the aperture 104a, 104b it is held in place along its opposed longitudinal sides by the interior opposed longitudinal walls 105a, 105b of the aperture 104a, 104b and at its ends between the contacts 110a, 110b.
The width of each aperture 104a, 104b between the interior opposed longitudinal walls 105a, 105b is set to correspond to the diameter of an AA type battery. However, since the diameter of commercially available AA type batteries varies significantly, the interior longitudinal edges 105a, 105b of the apertures 104a, 104b may be lined with a strip of compressible rubber, which acts as a grommet, for receiving and holding the battery in place. This arrangement is shown in greater details in
The contacts 110a, 110b are coupled by wiring (not shown) which is internal to the body 102 to a circuit, which is shown schematically at 114, which is also inside the body 102. Further details of the circuit are provided in relation to
The overall dimensions of the charger 100 are such that it can be inserted into a credit card slot/compartment of a wallet or purse. The dimensions of a credit card are set by the international standard ISO/IEC 7810 under the ID-1 format as 85.60×53.98×0.76 mm. Consequently most wallets and purses include one or more slots to accommodate credit cards of these dimensions. In such wallets the slots are sometimes orientated ‘landscape’, whereby a longest edge of the credit card is inserted through the mouth of the slot, with the opposed longest edge protruding from the slot to allow a user to grip that edge prior to removing the card from the slot. In other wallets the slots are orientated ‘portrait’, whereby a shorter edge of the credit card is inserted through the mouth of the slot.
With reference
The circuit 114 is a DC-DC converter which converts an input voltage provided by a pair of AA type batteries 200, which together, when fully charged, provide a nominal voltage of around 3V. The circuit 114 is based around a MAX1708 chip 202 which is manufactured by Maxim Integrated, Inc. The MAX 1708 chip 202 is a step-up DC-DC converter which is capable of delivering up to 10 W of power at a fixed (3.3V or 5V) or adjustable (2.5V to 5.5V) output, using an on-chip power MOSFET from a 0.7V to 5V supply. A particular advantage of using this chip 200 is its small size, having a low profile, which is ideally suited to a charger which is to be fitted into a card slot of a wallet or purse.
In the embodiment described below, the components of the circuit (other than resistors R1 and R3 to R6) are chosen to produce a 5V output at a current of 0.5 A. This output voltage and current is a common current and voltage used to charge mobile phones, including iPhones (RTM) and other phones which require a micro-USB (RTM) connector. As is explained below, resistors R1 and R3 to R6 have the function of providing the appropriate voltages on connector pads J5 and J6 to allow the charger 100 to be used to charge specific mobile phones or other portable battery powered devices.
The components chosen to configure the MAX1708 chip 202 to provide a 5V output at connector pad J4 are as follows:
D1 Schottky diode for current regulation.
LI Inductor of 2.2 pH for charging the MAX1708 chip 202.
C3 capacitor 150 μP, and R2—resistor of 2Ω—C3 and R2 activate the MAX 1708 chip 202 and are connected to pins 10, 15 and 16 thereof.
R3—resistor of 75KΩ,
R4—resistor of 49.9KΩ,
R5—resistor of 75KΩ, and
R6—resistor of 49.9KΩ—R3, R4, R5 and R6 provide a pair of voltage dividers for data pins of iPhone. The voltage dividers are chosen to each provide voltages on connector pads J5 and J6 of 2V. When the charger 100 is used with an Apple (RTM) Lightning (RTM) connector to charge an iPhone, applying a voltage of 2V to the two data pins in this way set the iPhone to draw current at 0.5 A. NB When the charger is used to charge a phone using a micro-USB device, resistor R1 (shown within a broken line is not required) is required but resistors R3, R4, R5 and R6 are not required.
R1—resistor of 2Ω—R1 is only used when R3 to R6 are not required, e.g., for charging micro-USB devices. R1 is used to bridge connector pads J5 and J6 to supply 5V to any USB device at +,− output pins.
The MAX 1708 chip 202 demands a very specific layout both in proximity of certain components to certain pins on it and track width to allow necessary current flow and heat dissipation. The MAX1708 chip 202 also demands components with certain specifications, hence the choice of CI, C2, Dl and LI. For the present embodiment of the invention in order to provide a low profile charger 100 the components are chosen based on their ability to match the requirements of the MAX1708 chip 202 and their low physical profile.
The components of the circuit 112 are coupled to the MAX 1708 chip 202 by surface mounting the components and the MAX 1708 chip 202 on a PCB. In order to reduce the overall height of the circuit 112 the thickness of the PCB should be as small as possible and a PCB of thickness 0.2 mm has been used for this purpose.
As stated above, the components are chosen to provide a stable output voltage of 5V at connector pad J4. In other embodiments where a voltage other than 5V is required at connector pad J4 components having different values are to be used. As can be seen from
The charger 300 has a similar structure to the charger 100 shown in
As with the charger 100 of
In the embodiment of
As can be seen from
The major wall 1302 of the case 1300 has an aperture 1304 which is dimensioned to correspond to the major dimensions of the charger 100. Due to the similarity of the dimensions of the aperture 1304 and the charger 100, the charger 100 is held in place in the aperture 1304 by a snug compression fit. In the region of the connector 116 of the charger 100, the aperture 1304 may be oversized, so that there is no compression fit between the walls of the aperture 1304 and the connector 116, so that when the charger 100 is removed from the case 1300 the connector 116 will not snag in any way on the body 1308, thereby avoiding the risk of putting strain on the connector 116 when the charger 100 is removed from the body 1308.
In other embodiments of the case invention the charger the case may be arranged to form a continuous wall around the major wall of a mobile phone with partial or complete walls around the four peripheral walls of the phone, and the charger may be insertable into a cavity in the major wall.
As with each of the previous embodiments, the case/charger 1400 may incorporate a power cell, such as a rechargeable battery or other electrical storage cell, to be able to charge the portable device when no batteries are inserted in the battery apertures 1404, such that the batteries when inserted into the battery apertures 1404 will charge the internal cell and the device to which the connector 1408 is connected. Various modifications will be apparent to those in the art and it is desired to include all such modifications as fall within the scope of the accompanying claims.
For example, in the embodiments described above the chargers are powered by AA type battery, otherwise know as the Mignon or IEC-LR6 battery. In other embodiments of the invention the charger may be powered by other batteries. In other embodiments, the charger is powered by other cylindrical batteries such as AAA or CR2032 batteries. Where non-AA batteries are used, the apertures are dimensioned appropriately to receive such batteries. Furthermore, non-cylindrical batteries, such as the PP3 9V battery may be used. A particular advantage of AA type batteries is that they are the most widely available batteries.
In the embodiments described above, two AA batteries, each providing a nominal voltage of between 1.2 and 1.65 V (depending on the type) are used. In other embodiments, a single AA battery (or other cylindrical battery as described above) can be used. However, it has been found that in order to provide a voltage of a suitable current over the required period of time it is preferable to use two AA batteries, which are preferably fully charged.
Furthermore, for the chargers described with reference to
In the embodiments described above, the chargers are powered by one or more battery. In other embodiments the charger may additionally have a connector for connection to a USB (RTM) port of a computer or mains charger. The connector may be fixed to the body of the charger or it may be connected by a cable, which provides some flexibility between the connector and the body of the charger. The connector may be retractable within the body of the charger. An advantage of providing the charger with a USB connector is that the charger can be charged either from a USB port or, when the user is remote from a USB port, by one or more battery.
In the embodiment described with reference to
In the embodiments described above a MAX1708 chip 202 is used as the basis for the DC-DC converter. It is envisaged that other chips can be used to provide this function. In the embodiment of
Number | Date | Country | Kind |
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1501651.2 | Feb 2015 | GB | national |
1501720.5 | Feb 2015 | GB | national |
Filing Document | Filing Date | Country | Kind |
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PCT/GB2016/050232 | 2/2/2016 | WO | 00 |