GB2518840A

GB2518840A - A battery powered AC power source

Info

Publication number: GB2518840A
Application number: GB1317369.5A
Authority: GB
Inventors: Sharlein Smales
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-10-01
Filing date: 2013-10-01
Publication date: 2015-04-08
Anticipated expiration: 2033-10-01
Also published as: GB2518840B; GB201317369D0

Abstract

A wireless AC power supply apparatus comprises a power supply unit 10 and a battery charging unit. The supply unit comprises two batteries 18, 20 that are each separately removable from docking points 14, 15 in the device for charging in a dedicated charging unit, a plurality of appliance sockets 22, a switch to allow power to be supplied to the sockets from one of the batteries through an inverter and battery charge indicators 24a, 24b for displaying remaining battery charge in each of the batteries 18, 20. Thus the power supply unit can supply AC power to a plurality of outlets from one battery whilst the other is charged in a dedicated charger unit. This eliminates the need for trailing cables when providing AC power to appliances a substantial distance away from a wall mounted mains outlet. The apparatus may additionally comprise resonance RF or magnetic induction wireless power transmission means to transmit power from the charger unit to the power supply unit 10.

Description

A battery powered AC power source

Field of the Invention

The present invention relates to a battery powered AC power source, and in particular to a device to supply electrical power remote from a mains electrical supply: or more particularly but not exclusively a device to supply mains voltage power from a battery removable from the device.

Background

In offices and homes there is often the need to supply a number of separate mains powered devices at a location some distance from a wall and hence from a mains power socket, which are usually wall-mounted. Presently extension cables are used, but these have the drawback that they run across the floor and, for example, present a trip hazard.

Additionally there is sometimes the need to protect against temporary mains voltage fluctuations or outages, in particular for computing or medical equipment, for which a battery-based uninterruptible power supply (UPC) is often used. A power supply and distribution device that provides a local mains power supply without the need for trailing cables, and provides a degree of protection against power supply fluctuations would have widespread application. The prior art provides a number of devices that attempt to address this problem but they suffer from drawbacks, in particular that * :* 25 battery-based devices need to be charged and then used as a power supply -some can be used as a power supply while charging, but that does not achieve the * objective of avoiding the need for a cable connection. Prior art devices do not provide means to separate the charging and power supply functions within a single S...

device.

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Prior Art

Accordingly a number of patent applications have been filed in an attempt to resolve the problem or similar, including the following: W020091 51732 discloses a system and methodology for intelligent power management of wirelessly networked devices. The system provides for reliable wireless communication via a wireless power charging method and, a method to maintain power capacity of batteries in a wireless device. The batteries are charged via an RF harvesting unit embedded inside the wireless device. An intelligent wireless power charging system further comprises at least two batteries and at (east two RF adaptor devices coupled to an AC power line. The first adaptor is set for data communication while the second adaptor is used to transmit the power. In addition, when a first battery is in use during active mode, the second battery is subjected to wireless charging.

This device comprises two batteries permanently associated with the equipment, and uses only wireless power transmission, so the charge rate will be lower than for direct charging of a battery using electrical contacts. The device is not suitable for higher power applications such as to provide a portable AC power source.

W0201 301533 discloses a portable power supply having a built in battery, switch matrix, external voltage and impedance sensing means, inverter, and charging circuitry. The device uses a power plug for receiving AC from a wall electric receptacle; a transformer for transforming high voltage input to a low voltage output; a rectifier, for rectifying the low alternating voltage to direct voltage; at least one battery rechargeable by said direct voltage; an inverter, for inverting direct voltage supplied by the rechargeable battery to relatively low alternating voltage, which is supplied to the secondary winding of the transformer; and an alternating current (AC) socket, for receiving high voltage from the primary winding of the transformer. Both * AC and DC of various voltages may be supplied by this device in a portable manner, s... which uses a single transformer both for recharging batteries and for supplying AC power produced via the batteries. A switching assembly allows for connecting the S.....

* 30 batteries (which may be rechargeable) in a variety of topologies. S. S * S S * *S

U520100038974 discloses a method and apparatus for supplying cordless power to a remotely-located load device. A first power supply unit of a portable power supply system is configured to operate in a charge receive mode and/or a charge supply mode. When the first power supply unit is in the charge receive mode, a first energy storage device of the first power supply unit is configured to receive electrical energy via a first switch from one of a second power supply unit or an external power source.

When the first power supply unit is in the charge supply mode, the first energy storage device of the first power supply unit is configured to supply electrical energy via a second switch to one of a third power supply unit or a remotely-located load device.

This device provides a common charger unit and a plurality of power supply devices, each one being able to supply a single load.

US200701 41403 discloses an* enclosure or casing that will contain a rechargeable battery which can be inserted from the side. An adapter and a battery recharge socket is attached to the side of the casing allowing for stored power. The back panel has AC type sockets which will operate anything that use AC power. The carry handle provides a means to transport the unit from place to place. An on and off switch allows the pack to be used at chosen times. An inverter circuit is applied inside to change the source of power form DC to AC. The base is square to allow user to position the unit without tilting. The difference in the design is the capability of changing DC current to AC current.

This device comprises a single battery that may be removed from the device and replaced. The battery is charged in situ in the device.

In contrast the present invention provides a means to provide AC power that overcomes the drawbacks mentioned above.

Summary of the Invention *. .

* According to the present invention there is provided a power supply apparatus *."., comprising: *00* a power supply device comprising: (i) a housing comprising at least a first and a second battery docking points each comprising a recess in the housing adapted to receive a battery, the first docking point comprising a first contact means, and the second docking point comprising a second contact means, and one or more power sockets; (ii) a first and a second rechargeable battery, each battery being removable from the device and adapted to dock to the first and second docking points so as to make an electrical connection to the contact means; (iii) an inverter to convert a DC supply from a battery to AC main voltage, the iriverter having an output connected to the one or more power sockets; (iv) switch means configured to connect the inverter input to one of the first or the second contact means; (v) a control means configured to measure the level of charge in one or more batteries docked to the docking points and to control the switch means to connect the inverter input to one of the first or the second contact means; and a charging unit comprising: (i) one or more docking positions each adapted to receive a battery adapted for use with the power supply device; and (ii) a power supply means adapted to connect to a mains power supply and to provide a DC electrical supply to the one or more batteries; In some embodiments the first and the second battery are separately removable from the device.

In some embodiments the device comprises indicator means to indicate the state of charge of each battery.

In some embodiments the device comprises indicator means to indicate that a battery is in use to supply power to the power sockets.

In some embodiments the device comprises indicator means to indicate that a battery is not in use to supply power to the power sockets and may be removed from the device. * * * * *

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* In some embodiments the device comprises a power on/off switch to control the supply of power to the power sockets. In some further embodiments the device **** * comprises a timer or power saver switch to monitor, suspend or taper energy usage. * 30

*. In some embodiments the device is configured to stand on its lower surface and the * ** one or more power sockets are provided on the top surface of the device.

In some embodiments the battery docking points are provided on one or more sides of the device. In other embodiments the batteries may be inserted into the top of the device. In some embodiments the batteries may be slid and clicked into docks with spring biased release mechanisms to aid in efficiency of usage.

In some embodiments the device comprises interlock means configured to prevent removal of a battery while it is in use to supply power to the power sockets.

In some embodiments the interlock means is configured to prevent such removal when the power on/off switch is in the on condition and configured to allow such removal when the switch is in the off condition.

In some embodiments the first and second docking points are provided at a first and a second height above the base of the device such that at least a portion of the first battery lies above the second when the batteries are docked in position.

In some embodiments the batteries comprise a battery housing comprising one or more battery cells and a handle projecting from the housing. The device may be configured such that the handle projects from the device when the battery is docked.

Further embodiments have a hinged, telescopic or extendable handle or lanyard attachment points for transport.

In some embodiments the battery housing is substantially disc shaped having contacts to the battery cells on its lower major surface. In some embodiments the device is rotatable andor tiltable to aid in docking and/or general socket usage..

In some embodiments the battery cells are lithium ion polymer battery cells. In preferred embodiments at least two or more such battery cells are separately or * divisibly provided in use. In some embodiments battery load may be correlated or *..*** * indicated on a monitor, indicia or display: wherein number of batteries or cells in use, or required, or remaining charge thereon may be monitored or indicated. S.-.

****** * 30 In some embodiments the charger unit comprises at least one recess in its top * : .: surface adapted to receive a battery. Preferably level of charge is indicated locally or *:. remotely, for example wherein an audible or visual alert may be registered on obtaining charge levels, or wherein wireless or intermachine connectivity or operability is enabled.

Wireless power transmission is known using a mains powered RF transmitter and an RF receiver connected to a load, typically charging a battery to provide a smoothed source of stored power. However, where wireless power transmission provides a relatively low energy transfer rate, it is best used to charge a battery that will experience a low load and in situations where higher loads are likely to be used, perhaps intermittently, it is advantageous to provide a flexible means of providing power in a cable-free manner, comprising more than one mode of delivering power to a power supply device.

In some embodiments the apparatus further comprises wireless power supply means, the charging unit comprising a mains powered wireless power transmission means and the device comprising a wireless power receiving means.

In some embodiments the charging unit comprises a power transmission means comprising a transmission coil, an oscillator and a power amplifier means to energise the coil and the power supply device comprises a receiving coil and a battery charging means adapted to receive energy from the receiving coil and to charge a battery docked to the power supply device.

In this way the wireless power supply means may charge a battery in situ in the power supply device gradually, for example while not in use, as suits the power supply capacity of the wireless transmission means. In general, charging of a battery placed in the charger unit will be faster than by wireless power transmission as the power transfer rate will be larger.

** In this way the apparatus of the invention comprising both charging means provides * * the advantages of both: a gradual charge of the battery by wireless power transmission and a more rapid charging when needed by removing a battery from the power supply device and placing it in the charger unit. The charger unit may be 30 adapted to charge one or both batteries docked to it by wireless power transmission means, for example to charge the battery that is not in use. * .

* In some embodiments the power transmission means is a resonance power transmission means as known in the art. In this way the power supply device may receive power at a distance from the charger unit.

In some embodiments the power transmission means is a magnetic induction power transmission means. In this way the power supply device needs to be placed near or on the charger unit for magnetic induction coupling to occur. This has the advantage that higher wireless power transfer rates can be achieved, and the batteries in the power supply device may be charged both at the same time and do not need to be removed from the device. Again, in this way the apparatus of the invention provides the advantages of more than one way of using the apparatus according to the circumstances.

Brief Description of Figures

Figure 1 shows an isometric view of an embodiment of a power supply device according to the invention.

Figure 2 shows a first side view of the embodiment in figure 1.

Figure 3 shows a second side view of the embodiment in figure 1.

Figure 4 shows a top view of the embodiment shown in figure 1.

Figure 5 shows an exploded view of the embodiment shown in figure 1.

Figure 6 shows an isometric view of an embodiment of a charger unit according to the invention.

Figure 7 shows an exploded view of the embodiment shown in figure 6.

Detailed Description of Figures

Referring to figures 1 to 7, an embodiment of a power supply apparatus according to the invention comprises an embodiment 10 of a power supply device and an embodiment 30 of a charger unit.

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Referring to figures Ito 5, an embodiment 10 of a power supply device according to **.

the invention comprises: S.....

* 30 (i) a housing 12 comprising at least a first 14 and a second 15 battery docking points *. each comprising a recess 18 in the housing adapted to receive a battery 18, 20, the . first docking point 14 comprising a first contact means 17 and a second docking point comprising a second contact means 19, and one or more power sockets 22, here shown as UK standard 3 pin sockets, (ii) a first 18 and a second 20 rechargeable batteries each removable from the device and adapted to dock to the docking points so as to make an electrical connection to the contact means, (iii) an inverter to convert a DC supply from a battery to AC main voltage, the inverter having an output connected to the one or more power sockets (iv) contact switch means configured to connect the inverter input to one of the first or the second contact means (v) a control means configured to measure the level of charge in one or more batteries docked to the docking points and to control the switch means to connect the inverter input to one of the first or the second contact means, and A charging unit 30 comprising: (i) one or more docking positions 32 each adapted to receive a battery adapted for use with the power supply device and comprising charging contact means 34 adapted to make contact with contact means provided on the battery when the battery is in place in the docking position 32, (ii) a power supply means adapted to connect to a mains power supply and to provide a DC electrical supply to the one or more batteries In this embodiment the first and the second battery are separately removable from the device.

In this embodiment the batteries each comprise one or more lithium ion polymer battery cells.

The device further comprises indicator means 24a, 24b to indicate the state of charge of each battery, for example a row of LED5. This indicator means also indicates that a battery is in use to supply power to the power sockets. In some embodiments the indicator means comprises a row of green LEDs. A red LED may be provided to illuminate when a battery is out of charge and may be removed from ? 30 the device for charging. 0 *

7 The device comprises push button switches 26a, 26b check the state of charge of * *.

* each battery. Push buttons 26a, 26b may also be used in some embodiments to check that a battery is not in use to supply power to the power sockets and may be removed from the device.

The device comprises a power on/off switch 28 to control the supply of power to the power sockets.

In this embodiment the housing 12 is substantially cylindrical and comprises four power sockets arranged at 90 degree intervals around the top surface of the housing, and the first docking point 14 is provided at a first position on the side of the cylinder and the second docking point 15 at a second position substantially diametricaHy opposite the first. The first docking point 14 is provided at a first height above the base of the cylinder and the second docking point 15 at a second height, below the first1 as shown in the figures. In this way the device is adapted to receive two batteries 18, 20 into the housing such that when docked the first battery 18 is located above the second 20. In this way two batteries may be accommodated conveniently stacked within the housing. The batteries 18, 20 each comprise a substantially disc-shaped battery housing 40 having an upper surface 42, a lower surface 44 and a handle 46 projecting from the side of the disc. The recess 16 is adapted to receive the battery housing to a depth that the handle 46 projects beyond the side of the device housing 12 when the battery is docked, allowing the battery to be removed easily. The battery comprises a battery means within the housing, preferably comprising one or more lithium-ion polymer cells as known in the art, and battery contact means provided on the lower surface 44 of the battery housing. The contact means 17, 19 (not shown in the figures) provided associated with the docking points are therefore provided on the upward-facing surface of the recess 16.

Referring to figure 5, the device housing 12 comprises a main casing 50, a first battery casing 52, a second battery casing 54 and a base 56, adapted to fit together.

The device comprises a PCB 60 mounted above the first battery casing 52 and * * directly below the top portion of the main casing, to accommodate the inverter, the contact switch and the control means, light sources such as LEDs for the indicators *...

24a and 24b, the on/off switch 28 and preferably power socket contacts forming the * 30 electrical contact part of the power sockets 22. The device preferably comprises ". : over-current protection means to prevent excessive currents being drawn from the * ** * power supply sockets. Such over-current protection means may comprise one or more bimetallic cut-out switches, mounted on the POB or elsewhere in the housing.

The main casing 50 comprises apertures 58 to allow pins of power plugs to connect to the power supply output contacts mounted on the PCB, lenses for indicators 24a and 24b, and buttons to actuate the battery check switches 26a, 26b and the on/off switch 28 mounted on the PCB. The first and second battery housings each comprise contact means 17, 19 to contact to the battery contact means.

Referring to figure 7, the charger unit 30 comprises a substantially disc shaped housing 36 having a cylindrical recess 32 adapted to receive the battery housing 40, and a recess 33 adapted to receive the handle 46 of the battery. In this way the battery fits snugly into the charger unit and is oriented when in place in the recess such that the battery contacts are aligned with and come into contact with the charger unit contact 34. The charger unit has a base 37 and comprises a PCB 38 accommodating the mains power supply means for charging the battery. The charger unit comprises indicator means 39 to show the state of charge of the battery, for example a row of LEDs, connected to the PCB, and a mains supply lead 31.

In some embodiments the charging unit comprises a power transmission means comprising a transmission coil mounted within the housing 36, for example on the base 37, an oscillator and a power amplifier means on the PCB 38 to energise the coil, and the power supply device 10 comprises a receiving coil mounted within the housing 12, for example on the base 56, and a battery charging means on the POB adapted to receive energy from the receiving coil and to charge a battery docked to the power supply means. :

* * In some embodiments the power transmission means is resonance power * *.. transmission means as known in the aft. * ***.

* 30 In some embodiments the power transmission means is a magnetic induction power *°. : transmission means as known in the aft. * S.

S *..

The housings may be formed from moulded polymer, for example ABS, which has good electrical insulation and mechanical properties. The bases of the power supply device and the charger unit may be formed from TPE-coated ABS to give non-slip properties.

In use the user first plugs the charger unit into the mains power supply and places a battery into the charger unit. The battery will begin charging straight away. When all five green LEDs are illuminated on the charging unit, the user will know the battery is charged. The charged battery is then docked into a docking point on the power supply device. Meanwhile, the user can start to charge the second battery. With the products the user wants to power plugged in, they press the red button on top of the muti-plug unit to turn it on When the second battery is charged it can be docked into the power supply unit. The user interface will use five green LEDs to show how much power is left in the battery that is being used. When the first battery is out of charge the power usage will be switched automatically to the second fully charged battery.

One red LED will illuminate to show that the used battery is ready for recharging.

The invention has been described by way of examples only and it will be appreciated that variation may be made to the above-mentioned embodiments without departing from the scope of invention.

With respect to the above description then, it is to be realised that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.

Therefore1 the foregoing is considered as illustrative only of the principles of the * invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and * * S... . . . . . equivalents may be resorted to, falling within the scope of the invention as set out in * 30 the accompanying claims. S. * * I. * S.

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