U.S. patent number 7,471,062 [Application Number 10/170,034] was granted by the patent office on 2008-12-30 for wireless battery charging.
This patent grant is currently assigned to Koninklijke Philips Electronics N.V.. Invention is credited to Gert W. Bruning.
United States Patent |
7,471,062 |
Bruning |
December 30, 2008 |
Wireless battery charging
Abstract
Batteries in portable electrical or electronic devices are
charged, through by a wireless battery charger, having an
intermediate electrical energy storage device that is charged from
a non-power line connected source, and discharged to recharge the
battery of a portable device placed into a charge port of the
wireless battery charger. The non-power line connected source may
be a solar cell for converting light impinging on the solar cell
into electrical energy. The non-power line connected source may
also be a fuel cell for converting a fuel into electrical energy.
The wireless battery charger may also include multiple sources,
such as both a solar and a fuel cell. Charging the intermediate
electrical energy storage device from the non-power line connected
source may take place over an extended period of time having a
duration longer than the time required to charge the battery of the
portable device. The wireless battery charger and portable device
may include transformer elements that allow the battery of the
portable device to be re-charged by magnetic induction, without the
need for electrical contacts in either the charger port or on the
portable device.
Inventors: |
Bruning; Gert W. (Sleepy
Hollow, NY) |
Assignee: |
Koninklijke Philips Electronics
N.V. (Eindhoven, NL)
|
Family
ID: |
29732407 |
Appl.
No.: |
10/170,034 |
Filed: |
June 12, 2002 |
Prior Publication Data
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Document
Identifier |
Publication Date |
|
US 20030231001 A1 |
Dec 18, 2003 |
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Current U.S.
Class: |
320/108 |
Current CPC
Class: |
H02J
7/35 (20130101); H02J 7/342 (20200101); H02J
7/025 (20130101); H02J 50/10 (20160201); H02J
50/005 (20200101); H02J 50/402 (20200101) |
Current International
Class: |
H01M
10/46 (20060101) |
Field of
Search: |
;320/108,112,106,110,113,114,101,145,162,103,109,137,140
;307/18,19,20,46,150,43,66,414 ;323/906 ;136/243,244 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Tso; Edward
Attorney, Agent or Firm: Belk; Michael E.
Claims
I claim:
1. An apparatus for charging a battery in a portable device, the
apparatus comprising: a non-power-line-connected source of
electrical charge; an intermediate storage device for storing the
electrical charge to serve as a primary source for recharging the
battery in the portable device; a source charger/converter for
charging the intermediate storage device with an electrical charge
received from the non-power-line-connected source; and a transfer
charger/converter for delivering the stored electrical charge from
the intermediate storage device to the battery in the portable
device, wherein the source charger/converter transfers the
electrical charge to the intermediate storage device over an
extended period of time that is longer in duration than a period of
time required for delivering the stored electrical charge to the
battery of the portable device.
2. The apparatus of claim 1 wherein the intermediate storage device
includes a battery.
3. The apparatus of claim 1 wherein the source charger/converter
includes a direct current to direct current (DC/DC) converter.
4. The apparatus of claim 1 wherein the non-power-line-connected
source includes a solar cell for converting light energy into the
electrical charge.
5. The apparatus of claim 1 wherein the non-power-line-connected
source includes a fuel cell for generating the electrical
charge.
6. The apparatus of claim 1 wherein the transfer charger/converter
includes an electrical connector adapted to receive and establish
an electrical connection with a mating electrical connector on the
portable device, for delivering the stored electrical charge to the
battery of the portable device.
7. The apparatus of claim 1 wherein the stored electrical charge is
delivered to the battery of the portable device without the use of
an electrical connection between the intermediate storage device
and the portable device.
8. The apparatus of claim 7 wherein the transfer charger/converter
includes elements for generating an alternating current from the
stored charge, a transformer, and elements for converting
alternating current to direct current, for delivering the stored
electrical charge from the intermediate storage device to the
battery of the portable device by magnetic induction.
9. The apparatus of claim 1 wherein the source charger/converter
includes elements for receiving the electrical charge from the
source without the use of an electrical connection between the
intermediate storage device and the portable device.
10. The apparatus of claim 1 further including both a solar cell
and a fuel cell as non-power-line-connected sources of the
electrical charge.
11. A method for charging a battery in a portable device, the
method comprising: charging an intermediate storage device with an
electrical charge received from a non-power-line-connected source;
storing the electrical charge in the intermediate storage device as
a primary source for recharging the battery in the portable device;
and delivering the stored electrical charge from the intermediate
storage device to the battery in the portable device, wherein said
charging the intermediate storage device with the electrical charge
over an extended period of time that is longer in duration than a
period of time required for delivering the stored electrical charge
to the battery of the portable device.
12. The method of claim 11 wherein the intermediate storage device
includes a battery, and the method further comprises performing a
DC/DC conversion of the electrical charge.
13. The method of claim 11 wherein the non-power-line-connected
source includes a solar cell and the method further comprises
converting light energy impinging on the source into the electrical
charge.
14. The method of claim 11 wherein the non-power-line-connected
source includes a fuel cell and the method further comprises
converting fuel in the fuel cell into the electrical charge.
15. The method of claim 11 further including establishing an
electrical connection between the intermediate storage device and
the portable device, for delivering the stored electrical charge to
the battery of the portable device.
16. The method of claim 11 further comprising delivering stored
electrical charge to the battery of the portable device without the
use of an electrical connection between the intermediate storage
device and the portable device.
17. The method of claim 16 further comprising delivering the stored
electrical charge from the intermediate storage device to the
battery of the portable device by magnetic induction.
18. The method of claim 11 wherein the apparatus further includes
both a solar and a fuel cell as non-power-line connected sources of
electrical charge and the method includes charging the intermediate
storage device with an electrical charge received from at least one
of the solar and fuel cell sources.
19. An apparatus for charging a battery in a portable device, the
apparatus comprising: a non-power-line-connected generator of
electrical charge, an intermediate storage device for storing an
electrical charge, means for charging the intermediate storage
device with the electrical charge received from the
non-power-line-connected source; and means for delivering the
stored electrical charge from the intermediate storage device to
the battery in the portable device as a primary source for
recharging the battery in the portable device, wherein the
non-power-line connected generator of electrical charge, the
intermediate storage device, the means for charging the
intermediate device, and the means for delivering the stored
electrical charge are all provided in a common encasing, and
wherein the means for charging transfers the electrical charge to
the intermediate storage device over an extended period of time
that is longer in duration than a period of time required for
delivering the stored electrical charge to the battery of the
portable device.
20. The apparatus of claim 19 further comprising means for
delivering the stored electrical charge from the intermediate
storage device to the battery of the portable device by magnetic
induction.
Description
TECHNICAL FIELD OF THE INVENTION
This invention relates to charging batteries in portable electrical
and electronic devices, and more particularly to charging such
batteries in circumstances where it is impossible or undesirable to
charge the batteries in the portable device using a battery charger
connected to a power line.
BACKGROUND OF THE INVENTION
There are many types of portable electrical and electronic devices
in use today that include rechargeable batteries, so that device
can be used without a cord connecting it to a wall socket connected
to a power line or grid. Examples of such cordless electrical
devices include power hand tools, bathroom appliances such as
electric toothbrushes and shavers, and kitchen appliances such as
mixers or electric knives. Examples of portable electronic devices
include cellular telephones, pagers, two-way radios, telemetry
equipment, personal data assistants (PDA), computers, hand held
video games, and audio entertainment devices such as portable
radios, compact disc (CD) players, and tape recorders. Normally the
batteries in these electrical and electronic devices are re-charged
by connecting the device through a cord directly to a power line,
or by placing the device in a charger connected by a cord to a
power line receiving electrical power from a municipal utility grid
or a generator.
There are circumstances, however, under which it is impossible or
undesirable to connect to a utility grid through a power cord, or
where it is preferable to use another source of power for
re-charging the battery. One such circumstance is encountered in
operating devices with re-chargeable batteries in a remote outdoor
location, perhaps outdoors while back-packing, canoeing, camping,
or skiing, where there is no access to utility power lines or
portable generators. Carrying extra disposable batteries in such
circumstances is not desirable due to extra bulk and weight that
must be carried both in and out of the wilderness, so that the
spent batteries can be responsibly disposed of in an
environmentally friendly manner.
It is also sometimes preferable for safety reasons to avoid the
need for connecting a charger to a wall socket, in a kitchen or a
bathroom for example, to preclude the risk of inadvertent
electrical shock.
In other instances, while it may be possible to run an electrical
cord to a charger, it is inconvenient to do so. For example, it is
common practice in busy restaurants to give paging devices that
vibrate and light up to patrons waiting for tables. These pagers
must be kept charged, and it may not be convenient to have an
electrical outlet adjacent the maitre d' station, or to run an
electrical cord to a remote outlet, for charging the pagers.
What is needed, therefore, is an improved apparatus and method for
recharging batteries in portable electrical and electronic devices,
in a manner that does not require the device or a charger to be
connected to a power line or a generator.
SUMMARY OF THE INVENTION
My invention provides such an improved apparatus and method for
recharging batteries in a portable electrical or electronic device,
through the use of a wireless battery charger, having an
intermediate electrical energy storage device that is charged from
a non-power line connected source, and discharged to recharge the
battery of a portable device placed into a charge port of the
wireless battery charger. The non-power line connected source may
be a solar cell for converting light impinging on the solar cell
into electrical energy. The non-power line connected source may
also be a fuel cell for converting a fuel into electrical energy.
The wireless battery charger may also include multiple sources,
such as both a solar and a fuel cell. Charging the intermediate
electrical energy storage device from the non-power line connected
source may take place over an extended period of time having a
duration longer than the time required to charge the battery of the
portable device.
In one form of my invention, the charge port contains electrical
contacts that mate with corresponding electrical contacts of the
portable device. In another form of my invention, the wireless
battery charger and portable device include transformer elements
that allow the battery of the portable device to be re-charged by
magnetic induction, without the need for electrical contacts in
either the charger port or on the portable device.
The foregoing and other features and advantages of my invention
will become further apparent from the following detailed
description of exemplary embodiments, read in conjunction with the
accompanying drawings. The detailed description and drawings are
merely illustrative of my invention rather than limiting, the scope
of the invention being defined by the appended claims and
equivalents thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a first exemplary
embodiment of an apparatus, according to my invention, for charging
a battery in a portable device;
FIG. 2 is a schematic representation of a second exemplary
embodiment of an apparatus, according to my invention, for charging
a battery in a portable device; and
FIG. 3 is a perspective drawing of a wireless charger in the form
of a relatively flat pad, according to my invention, incorporating
the elements of the second embodiment of my invention as shown in
FIG. 2.
BRIEF DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
FIG. 1 is a schematic representation of a first exemplary
embodiment of an apparatus 10, according to my invention, for
charging a battery 12 in a portable device 14. The apparatus 10
includes a wireless charger 16 having a non-power-line-connected
source of electrical charge, in the form of a solar cell 18 for
converting light energy impinging on the solar cell 18 into an
electrical charge, and an intermediate storage device, in the form
of a charger battery 20 for storing the electrical charge. The
wireless charger 16 also includes a source charger/converter, in
the form of a direct-current to direct-current (DC/DC) converter
22, for charging the charger battery 20 with the electrical charge
received from the solar cell 18. The wireless charger 16 further
includes a transfer charger/converter 24, having a transfer circuit
26 and a charger connector 28 adapted to mate with a mating
electrical connector 30 on the portable device 14, for delivering
the stored electrical charge from the charger battery 20 to the
battery 12 via a charging circuit 11 in the portable device 14.
The solar cell 18 and DC/DC converter 22 convert light impinging on
the solar cell 18 into electrical charge, and store electrical
charge in the charger battery 20 over an extended period of time
that is longer in duration than the time required for delivering
the stored electrical charge from the charger battery 20 to the
battery 12 of the portable electrical device 14. This approach of
storing the electrical charge in the charger battery 20 over an
extended period of time, and delivering it over a short period of
time, provides considerable advantage in comparison to charging the
battery 12 in the portable device 14 directly from the solar cell
18.
It is desirable that the electrical charge stored in the charger
battery 20 be transferable to the battery 12 of the portable device
14 in a reasonably short period of time, such as 15 to 30 minutes,
so that the device battery 12 can be quickly re-charged to an
operating condition, by a solar cell 18 that is small enough in
size to fit into the wireless charger 16. Desirable types of
non-power-line-connected power sources, such as solar cells and
fuel cells are often only capable of producing electrical charge at
a limited rate that would require many hours to fully re-charge the
battery 12 in the portable device 14, if the
non-power-line-connected source were used for directly charging the
battery 12 without the capability of storing the electrical charge
in an intermediate storage device, such as the charger battery
20.
Without the intermediate storage device 20 of my invention, the
solar cell 18 would have to be made much larger in order to produce
the electrical charge at a rate high enough for re-charging the
battery 12 of the portable device 14 in an acceptable period of
time. I contemplate that in many embodiments of my invention, the
solar cell 18 should be of sufficient size to re-charge the charger
battery 20 over an extended period of time in the range of six to
seven hours, under conditions where the solar cell 18 is exposed to
partial sunlight.
FIG. 2 is a schematic representation of a second exemplary
embodiment of an apparatus 10 according to my invention having a
wireless charger 16 that includes both a solar cell 18 and a fuel
cell 32, as non-power-line-connected sources for generating the
electrical charge. The fuel cell may take many forms. The fuel cell
32 may utilize a fuel, such as methanol (wood Alcohol) supplied to
a fuel reservoir in the fuel cell via a fuel fill port 34 of the
wireless charger 16, and be rechargeable by refilling the fuel
reservoir through the fill port 34. In other forms, the fuel cell
32 may be essentially "solid state," and non-rechargeable. Such a
solid state fuel cell is constructed of materials that generate
electrical energy by consuming a fuel element included in fuel cell
when it is constructed. Once the fuel is consumed, the solid state
fuel cell is replaced because it is not rechargeable.
The second embodiment 10 also utilizes magnetic induction, rather
than electrical connectors, for transferring the charge stored in
the charger battery 20 to the portable device battery 12. This is
accomplished in the second exemplary embodiment by including a VHF
inverter and the primary winding of a transformer in the transfer
circuit 26 of the charger 16, for wirelessly transmitting the
charge by magnetic induction to a secondary transformer winding and
a rectifier in the charging circuit 11 of the portable device
14.
I contemplate that a wireless charger 16, according to my invention
may be provided in a wide variety of physical embodiments. FIG. 3
shows one exemplary embodiment of a wireless charger 16, having
internal configuration similar to the one described above in
relation to FIG. 2.
The wireless charger of FIG. 3 is configured in the form of a
relatively flat pad 36 that provides a common mounting and encasing
for the solar and fuel cells 18, 32, the charger battery 20, the
source charger/converter 22, and the transfer charger/converter 24.
The top surface 38 of the pad 36 includes an opening that exposed
the solar cell 18 to light impinging on the pad 36.
The top surface 38 of the pad 36 also includes a pair of charging
ports 40, 42 adapted for receiving a pair of portable devices 14,
one in each of the charging ports 40, 42. The charging ports 40, 42
hold the portable devices 14 in an orientation that brings the
primary transformer winding of the wireless charger 16 into
proximity with the secondary transformer windings in the portable
devices 14, so that the batteries 12 in the portable devices 14 can
be charged through magnetic induction. The internal surfaces of the
charger ports 40, 42 are preferably closed imperforate extensions
of the top surface 38, forming an environmentally sealed enclosure
that precludes the entry of any liquid or foreign matter into the
pad 36.
The fuel fill port 34 is shown extending from one of the side
surfaces 44 of the pad 36, but could alternatively be positioned to
extend from the top surface 38, the bottom surface 46, or one of
the other side surfaces 44 of the pad 36.
I contemplate that a wireless charger 16 according to my invention,
in the form of the pad 36 as described above, having solar and fuel
cells 18, 32 and transferring charge by magnetic induction, would
have a wide variety of uses.
For example, such a pad could be readily carried by a person, or a
group of persons, back-packing in a remote area where there is no
access to electrical power from power lines or generators. The pad
36 is small and light-weight enough to be carried on the outside of
a pack to receive sunlight throughout the day, and used for
re-charging batteries in portable electronic devices such as
cellular telephones, pagers, or two-way radios when the
back-packers stop for the night, or to rest. The sealed
construction of the charger ports 40, 42, and use of magnetic
induction for transferring the charge allow the pad 36 to be used
even in rainy conditions without fear of water entering into and
damaging the wireless charger 16 or the portable devices 12, or
causing an electrical short in the connection between the wireless
charger 16 and the portable devices 12 being charged. When there is
insufficient sunlight to fully charge the batteries 12 in the
portable devices 14, the fuel cell 32 can be used. Since the fuel
cell 32 serves only as a backup to the solar cell 18, only a small
amount of fuel for the fuel cell would need to be carried. Fuel
cell fuels such as wood alcohol could also be used for the
additional purpose of helping to start campfires.
A pad 36 similar in construction to the one described above for use
in back-packing would also be well suited for use in a remote
construction site for re-charging portable electrical hand tools,
or at a maitre 'd station for charging pagers.
I also contemplate that a pad 36, having multiple sealed charging
ports 40, 42 as described above, but without the fuel cell, would
be well suited to home use for re-charging small portable
electrical devices in the bathroom, kitchen, or workshop.
In the bathroom, a wireless charger 16, according to my invention,
can be utilized for charging electric toothbrushes or an electric
shaver. Electric toothbrushes and shavers are typically only used
for a minute or two each day, while the bathroom lights are
typically burned for several hours a day as family members use the
bathroom. Ambient light impinging upon the solar cell 18, either
from sunlight coming through bathroom windows or from electrical
lighting in the bathroom for several hours a day while the bathroom
is in use, would provide ample energy for charging one or more
electric toothbrushes, or electric shavers that are only used for a
few minutes a day.
In a kitchen, a wireless charger 16 according to my invention can
be utilized for charging portable electrical utensils such as a
hand held food mixer, or an electric knife, which are used
infrequently for only a few minutes at a time, separated by long
periods of non use, during which ambient light impinging on the
solar cell 18 can be stored by the charger battery 20. Should the
battery 12 of the portable device 16 become discharged during use,
it can be recharged from the charge stored in the charger battery
20 far more rapidly that would be possible using the solar cell 18
alone. Because the battery 12 in the portable device 16 can be
quickly recharged, it can be made smaller and more lightweight than
it would otherwise be if it were required to store enough energy
delivered directly from a solar cell, to allow several minutes of
operation of the utensil.
A wireless charger 16 according to my invention having sealed
charger ports 40, 42 provides additional advantages for use in
either a kitchen or a bathroom in that there is no risk or
electrical shock, and in that if soapy water or food is spilled
onto the pad 36, it can easily be wiped or washed away from the
smooth imperforate surface of the sealed charger ports.
Although the forgoing description has utilized certain exemplary
embodiments of my invention, many changes and modifications can be
made without departing from the spirit and scope of the invention.
I wish to expressly point out that the various features and aspects
of my invention illustrated and described herein, with reference to
the exemplary embodiments, may be utilized in combinations other
than those described herein.
For example, it may be desirable in some embodiments of my
invention to equip the charger ports 40, 42 of a wireless charger
16 similar to the one depicted in FIGS. 2 and 3, with electrical
connectors 28 as illustrated in FIG. 1, rather than using magnetic
induction for transferring charge, as illustrated in FIGS. 2 and 3,
so that the wireless charger may interface with prior portable
devices 14 that do not have the charging circuit 11 of my
invention. The wireless charger 16 depicted in FIG. 1 may include
multiple non-power-line connected sources, such as the solar cell
18 and fuel cell 32 of FIGS. 2 and 3, or the wireless charger 16
depicted in FIGS. 2 and 3 may include only a single non-power-line
connected source.
I also contemplate that a wireless charging apparatus 10 according
to my invention may be integrally incorporated into and include
many other structures, such as articles of furniture, a rack for
holding pagers at a maitre 'd station, a back-back, a briefcase, a
purse, carrying cases for tools or electronic devices, or other
similar structures. I contemplate that a wireless charger 16 in the
form of a pad 36, according to my invention, may be made
alternatively be provided in a form that is rigid or flexible, flat
or curved, etc., to suit the needs of a particular application of
my invention.
The scope of my invention is limited only by the appended claims,
and all changes that come within the meaning and range of
equivalents are intended to be embraced therein.
* * * * *