U.S. patent application number 11/385477 was filed with the patent office on 2007-09-27 for apparatus and method for generating and storing energy in a portable energy storage device and using the stored energy to extend internal battery life.
Invention is credited to Walter R. Evanyk, Timothy William Long.
Application Number | 20070220773 11/385477 |
Document ID | / |
Family ID | 38531831 |
Filed Date | 2007-09-27 |
United States Patent
Application |
20070220773 |
Kind Code |
A1 |
Evanyk; Walter R. ; et
al. |
September 27, 2007 |
Apparatus and method for generating and storing energy in a
portable energy storage device and using the stored energy to
extend internal battery life
Abstract
A portable energy storage device that can be brought to a
desired operating condition (such as temperature) using an external
power source to save the power in internal power cell and, when the
external power source is disconnected from device to make it
portable, the internal power cell of the device automatically
provides output power to the load that is regulated by a pulse time
modulation control circuit that senses the desired operating
condition and provides power pulses to the load sufficient only to
maintain the desired operating condition thus extending the life of
the internal power cell in the portable device.
Inventors: |
Evanyk; Walter R.; (Plano,
TX) ; Long; Timothy William; (Sherman, TX) |
Correspondence
Address: |
WALTER R. EVANYK
3200 SHERRYE DR.
PLANO
TX
75074-4693
US
|
Family ID: |
38531831 |
Appl. No.: |
11/385477 |
Filed: |
March 21, 2006 |
Current U.S.
Class: |
34/96 |
Current CPC
Class: |
A45D 2001/002 20130101;
A45D 20/12 20130101; A45D 2001/045 20130101; A45D 20/30 20130101;
A45D 2020/126 20130101 |
Class at
Publication: |
034/096 |
International
Class: |
A45D 20/12 20060101
A45D020/12 |
Claims
1. Apparatus for extending the life of at least one battery in a
portable energy storage device having an energy storing and energy
consuming load and including device power losses, P.sub.L,
comprising: an external power source coupled to the portable energy
storage device to cause the energy load to store a desired residual
amount of power, P.sub.R; at least one internal energy cell for
supplying electrical power, P.sub.IN, to the energy consuming load
only when the external power source is disconnected and the device
is portable thereby extending the life of the at least one internal
energy cell; and a power regulating circuit coupled between the
energy consuming load and the at least one internal energy cell for
generating pulse time modulated signals that control the battery
power to the energy consuming load such that the input power,
P.sub.IN, substantially equals power losses, P.sub.L, thereby
enabling the stored residual power, P.sub.R, to provide the output
power, P.sub.O, and extend the life of the batteries.
2. The apparatus of claim 1 further comprising: a base unit for
receiving the portable device; and the external power source being
coupled to the base unit to provide power to the portable device to
enable it to store the desired kinetic/residual amount of
power.
3. The apparatus of claim 2 wherein the portable device is a hair
curling iron and the external power source preheats the hair
curling iron to a desired temperature.
4. The apparatus of claim 1 wherein the power regulating circuit
further comprises: a control circuit coupled between the at least
one internal energy cell and the energy storage load for generating
pulse time modulated signals that automatically reduce the at least
one energy cell input power, P.sub.IN, applied to the load to an
amount sufficient only to replace the power losses, P.sub.L,
thereby just maintaining the residual power, P.sub.R, to equal the
desired output power, P.sub.O, to conserve electrical power and
prolong the life of the load.
5. The apparatus of claim 2 wherein the external power source
simultaneously charges/recharges the at least one energy cell
whenever the device is in the base unit and the external power
source is providing power to the portable device to enable it to
store the desired residual amount of power.
6. The apparatus of claim 5 further including: the internal power
cell being in the form of at least one battery; and an AC/DC
converter associated with the base unit for converting the AC wall
socket power to DC power that is provided to the portable device to
enable it to store the desired residual amount of power while
simultaneously charging/recharging the at least one internal
battery.
7. A method of extending the life of at least one battery in a
portable energy storage device having an energy consuming and
storing load and power losses, P.sub.L, comprising the steps of:
supplying input power, P.sub.IN, to the device load from an
external power source to achieve the desired output power, P.sub.O,
with an accompanying residual power, P.sub.R and to simultaneously
charge/recharge the at least one battery as necessary;
automatically connecting the at least one battery to the load only
when the external power source is disconnected; and using variable
rate pulse time modulated signals to automatically reduce the input
power, P.sub.IN, supplied by the at least one battery to an amount
sufficient only to replace the power losses, P.sub.L, thereby just
maintaining the residual power, P.sub.R, equal to the desired power
output, P.sub.O, to conserve input power and prolong the life of
the load and extend the life of the at least one battery.
8. The method of claim 7 further comprising the steps of: placing
the portable energy storage device in a base unit; and coupling the
external power source to the base unit to cause the portable device
to store the desired residual amount of power supplied by the
external power source.
9. The method of claim 8 further comprising the steps of: forming
the portable device as a hair curling iron having the energy
consuming and storing load; and preheating the hair curling iron
load to a desired temperature with the external power source.
10. The method of claim 7 further comprising the step of: coupling
a control circuit between the at least one internal battery and the
energy storage load for generating pulse time modulated signals
that automatically reduce the at least one battery input power,
P.sub.IN, applied to the energy storage load to an amount
sufficient only to replace the power losses, P.sub.L, thereby just
maintaining the residual power, P.sub.R, to equal the desired
output power, P.sub.O, to conserve electrical power and prolong the
life of the at least one battery and the load.
11. The method of claim 8 further comprising the step of:
simultaneously charging/recharging the at least one battery
whenever the device is in the base unit and the external power
source is providing power to the portable device to enable it to
store the desired residual amount of power.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates in general to portable energy
storage devices such as, for example only, heat generating
elements. In particular, the invention relates to a hair curler, a
hair straightener, a flat clothes iron, or any other such device
for storing energy comprising a rotating flywheel, a light source,
or the like. The energy storage device uses an external power
source to bring the device to a desired operating condition thereby
conserving internal battery power and to simultaneously charge
internal batteries during the time that the device is placed in a
base unit. When the device is removed from the base unit, the
internally located batteries automatically provide energy to the
heating element to make the device portable. A Pulse Time
Modulation circuit regulates the battery power output at a level
sufficient only to replace power losses in the device, again
extending the life of the internal batteries.
[0003] 2. Description of the Prior Art
[0004] In commonly assigned, copending patent application Ser. No.
11/094,000, entitled Portable Energy Consuming Device, and
incorporated herein by reference in its entirety, there is
disclosed an energy storage device such as a hair curler, a flat
iron, a light source, or a rotating mass.
[0005] The device sits in a base unit when not in use. The base
unit is connected to an external power source for applying power to
the device to pre-energize the device to a predetermined level. For
example, if the device is a curling iron, the external power, when
the device is placed in the base unit, preheats the heating element
to a predetermined temperature. The heating element of the device
may be an AC heating element (in which case the external power
source is a conventional wall socket providing AC power for
preheating the device) or a DC heating element (in which case the
external AC power source is rectified to a DC voltage that is used
for preheating the device).
[0006] If an AC heating element is provided for preheating the
device, a second DC heating element is located adjacent the AC
heating element (which also preheats the DC heating element) and
when the device is removed from the base unit, an internal DC power
source is automatically connected to the DC heating element to
maintain the existing preheat value.
[0007] Obviously the use of an external power source to
pre-energize the device to a predetermined level (e.g. a
predetermined temperature) extends the life of the internal
batteries since the battery power is not expended in pre-energizing
the device to the predetermined level. Such a system is disclosed
in U.S. Pat. No. 6,664,516 which uses a PTC (positive temperature
coefficient) thermistor that enables a high current to be provided
to the heating element initially. However, as the time of
application of the voltage increases, the electric current will
decrease sharply until it reaches a low level whereupon it will
remain relatively constant. Thus, power applied to the load is
regulated by the PTC element serving as the load.
[0008] A device is disclosed in U.S. Pat. No. 4,857,702 that
utilizes an external power source to recharge the internal
batteries. This device requires the use of an AC wall socket plug
that is pivotally mounted in the side of the device handle. When
the plug is pivoted outwardly, it forms connections internally of
the device to recharge the batteries. If the device is unplugged
from the wall socket and the AC wall socket plug is pivoted
inwardly of the body or handle, it provides internal connections
that allow the charged batteries to heat the heating element. It
will be seen that the battery cannot be charged while the heating
element is being heated and the heating element cannot be heated
while the battery is being charged.
[0009] As stated above, these devices prolong the life of the
internal batteries by preheating the element with an external power
source and, thus, saving the battery energy for simply supplying
power to the heating element to maintain its heat.
[0010] As recognized in copending, commonly assigned, U.S. patent
application Ser. No. 11/094,729, incorporated herein in its
entirety by reference, an energy consuming device operates
according to the well known equation P.sub.O=P.sub.IN-P.sub.L (1)
where P.sub.O=Power output, P.sub.IN=Power input, and P.sub.L=Power
losses associated with the device.
[0011] However, if the device is an energy storage device, when the
energy storage device reaches its operating condition (e.g. desired
temperature, rotational speed, momentum, and the like), residual
power, P.sub.R becomes a factor in equation (1) above which becomes
P.sub.o=P.sub.in-P.sub.L+P.sub.R (2) where P.sub.R=Residual Power
and where "Residual Power" or "Residual Energy" is defined as
"residual heat", "rotational energy", "mass momentum", "linear
motion", "dynamic energy", or any other term representing
"potential energy" or "kinetic energy" in a device that is stored
by the applied power. The residual power or a energy can be used to
conserve energy used by such a device.
[0012] It can be seen in equation (2) that if P.sub.IN is reduced
to equal P.sub.L, then the residual power, P.sub.R, is sufficient
to maintain the desired output power, P.sub.O. If the residual
power, P.sub.R, is small, such as with a small electrical motor,
because of low inertia and mass, only a small amount of energy can
be conserved.
[0013] In particular, the invention relates to a method and
apparatus for providing a portable energy storage and consuming
device that has an external power source to cause the device to
reach its desired operating condition (set forth above), an
internal power supply for supplying power to the load of the
portable device only when the external power source is
disconnected, and a pulse time modulation device coupled between
the internal battery or energy cell and the energy consuming and
storing load to obtain a desired output power, P.sub.O, from the
electrical load by simply supplying sufficient pulse time modulated
energy, P.sub.IN, to the load to replace only load losses, P.sub.L,
and to maintain only the residual power, P.sub.R, thus maintaining
the desired power output, P.sub.O, and thereby conserving input
energy, P.sub.IN, that would otherwise be wasted.
[0014] It is known to manually adjust input power to maintain a
desired load. A circuit that is manually controlled to set a
desired temperature is disclosed in commonly assigned U.S. Pat. No.
6,449,870 and U.S. Pat. No. 6,718,651.
[0015] Also, there are soldering devices that have a control
circuit that shuts the power to the tip OFF when a certain
temperature is reached and then turns the power ON again when the
temperature falls below a desired temperature level. While it is
done automatically, the power is not continuously regulated by a
circuit that automatically varies the rate of pulsed (Pulse Time
Modulation) power applied to the load to continuously maintain a
desired operating condition such as temperature.
[0016] For a rotating energy storage device, such as a wheel,
motor, and the like, when input power to the rotating device is
removed, the motor or wheel continues to rotate by means of stored
energy until frictional energy (power losses) completely expends
the stored energy (residual power).
[0017] One circuit for manually providing input power, P.sub.IN, in
an amount equal to the power losses, P.sub.L, is disclosed in
commonly assigned U.S. patent application Ser. No. 11/055,235,
incorporated herein by reference in its entirety.
[0018] It would be very desirable to have an improved device that
provides continuous externally supplied electrical input power to
an electrical energy storage device until the device reached its
selected desired operating condition as long as the device is
placed on a base unit during which time the internal batteries are
charged and recharged. After the desired operating condition is
reached (e.g. desired temperature), the device can be made portable
by removing the device from its base by which action internally
located batteries are automatically coupled to a heating element to
continue to supply power to the device. An included novel circuit
in the device then automatically reduces the input power from the
batteries to the load (with the use of Pulse Time Modulation
controlled by a feedback circuit) to an amount sufficient only to
replace power losses to maintain just the residual power thus
maintaining the desired power output with a minimum of power input
thereby prolonging the battery life.
SUMMARY OF THE INVENTION
[0019] Thus, the present invention relates to an improved portable
energy storage device (such as a hair curler and/or a hot air
brush, flat iron, rotating mass, and the like) that utilizes an
external power source to cause the device reach its desired
operating condition (e.g. temperature, speed, momentum, and the
like) and then utilizes internal batteries with a regulated pulse
time modulated output as a power source providing sufficient power
only to replace power losses, P.sub.L, and to make the device
portable.
[0020] As used herein, the term "external power source" means any
one of AC, DC, RF energy, magnetically coupled energy, and the
like. Hereafter, for simplicity, the term will be identified as
simply AC or DC. The energy consuming device, when a temperature
controlled device, may have either a single heating element for
accepting an external DC power source output for preheating as well
as the internal power source (at least one battery) output to
maintain the desired operating level or an AC heating element for
connection to an external AC power source to obtain the desired
operating level and a separate DC heating element for connection to
the internal power source to maintain the desired operating
level.
[0021] With the present invention, an electrical energy storage
device is brought to its desired operation condition by applying
full input power, P.sub.IN, from an external power source as
explained earlier until the desired operating condition is reached.
Thus, the device is caused to store the desired potential energy
without using the internal batteries (i.e. extending the battery
life). At that point, the input power, P.sub.IN, is automatically
reduced with the novel Pulse Time Modulation circuit disclosed in
commonly assigned copending patent application Ser. No. 11/094,729,
incorporated herein by reference in its entirety, to the amount of
power losses, P.sub.L, occurring in the device and thus enables the
residual power or energy, P.sub.R, that is stored in the device to
substantially equal the desired output power, P.sub.O.
[0022] This is accomplished by providing a feedback circuit
representing the desired operating condition of the energy storage
device (i.e. temperature, rotational speed, light brightness, and
the like) and generating a signal representative of the
instantaneous value of the desired operating condition. That
generated feedback signal is coupled as one input to a comparator.
The other input is a variable time based electrical reference
signal such as, for example only, a sawtooth reference waveform.
When the feedback signal is less in amplitude than any portion of
the sawtooth reference waveform, the output of the comparator is a
pulse time modulated signal (PTM) that is coupled to, and actuates
an electronic switch such as a power FET. The electrical load
receives power from the power input source only when the electronic
switch is actuated. The pulse time modulated signal is coupled to
the gate of the electronic switch to automatically switch it ON and
OFF at a rate sufficient to supply just enough power to the load to
replace power losses (e.g. cooling in a heat storage device) and
thus maintains the desired operating condition as determined by the
feedback signal.
[0023] Also, for the improved circuit disclosed herein, where the
input feedback signal is generated by a temperature sensor that
provides a small input signal that must be amplified such as by a
transistor, a fixed-bias may be provided to the base of the
transistor rather than using self-biasing to form sharp, clean,
pulses that are free from parasitic oscillation, 60 cycle hum, and
the like.
[0024] The novel circuit, when controlling a portable light source,
may use a feedback signal proportional to the heat of the light
bulb filament or the light brightness as determined by any
well-known light sensor, such as a cadmium-sulfide cell or a
photo-detector, and thus provide power sufficient only to
compensate for load losses such as filament cooling, and the
like.
[0025] When controlling a portable rotating device that has
momentum (stored energy or kinetic energy, the rotational speed of
the device, as detected by an rpm indicator, for example only, can
be used to generate a signal representative of the rotational speed
and that signal can be used as the feed back signal, as described
above, to drive the rotating device at a desired speed by supplying
pulse time modulated signals to an electronic switch to apply power
to the load sufficient only to compensate for load losses such as
friction, system losses, and the like.
[0026] Thus, it is an object of the present invention to extend the
life of batteries in a portable energy storage device by using an
external power source to provide the power necessary to obtain a
desired output power from an electrical load (such as to preheat an
electrical load to a desired temperature), disconnecting the
external power source and automatically connecting the batteries to
the load and then using a Pulse Time Modulation circuit to regulate
the battery power output to replace only the system and load losses
thereby enabling any Residual Power associated with the load to
equal the desired output power and therefore conserve battery input
power and extend the life of the batteries.
[0027] It is another object of the present invention generate a
feedback signal representing the desired operating condition of the
load, compare the feedback signal with a variable time based
electrical reference signal and generate the Pulse Time Modulated
signals based on the comparison.
[0028] It has been found, in actual tests, (depending upon the type
of energy storage device tested) that applying as little as 10% of
the continuous maximum battery voltage to the load may be
sufficient to maintain the desired operating condition such as
temperature. This novel control circuit can be advantageously used
with existing alternating current devices to minimize power
use.
[0029] To accomplish this novel battery saving operation, a heat
sensor, such as a tempistor or thermistor, and preferably an LM 34
thermistor made by National Semiconductor, provides the proper
control.
[0030] In addition, it is an object of the present invention to
provide a portable energy storage device comprising an external
power source to bring the device load to a desired operating
condition, internal batteries to power the device only in its
portable state, and an electrical circuit coupled between the
internal power source and the load for using pulse time modulated
signals for regulating the power applied to the load in an amount
sufficient only to maintain the stored energy of the device at the
desired operating condition so as to conserve and extend internal
battery life.
[0031] Thus, the present invention relates to apparatus for
extending the life of batteries in a portable energy storage device
comprising an external power source for causing the device load to
reach a designated operating condition, P.sub.O; an internal power
source in the device for supplying input power, P.sub.IN, to the
load only when the external power source is disconnected from the
device and making the device portable; and a pulse time modulated
circuit coupled between the internal power source and the load for
using pulse time modulated signals to cause input power, P.sub.IN,
to be supplied to the load in an amount substantially equal to the
device power losses, P.sub.L, sufficient only to maintain the
designated operating condition, P.sub.O.
[0032] The present invention also relates to a method of extending
battery life in a portable energy storage device and obtaining a
desired output power, P.sub.O, from an electrical load, where
P.sub.O=P.sub.IN-P.sub.L+P.sub.R, comprising the steps of:
supplying a continuous external power input, P.sub.IN, to the load
to achieve the desired output power, P.sub.O, and create a
residual, or stored power, P.sub.R; disconnecting the device from
the external power source and automatically causing internal
batteries to drive the load; and automatically reducing the input
power, P.sub.IN, to an amount sufficient only to replace system and
load losses, P.sub.L, using Pulse Time Modulation to thereby
maintain the desired power output, P.sub.O, equal to the residual
power, P.sub.R, with reduced input power, P.sub.IN.
[0033] The present invention also relates to apparatus for
extending battery life in a portable energy storage device and
automatically obtaining a desired output power, P.sub.O, from an
electrical load of a system with reduced input power, P.sub.IN,
where P.sub.O=P.sub.IN-P.sub.L+P.sub.R where P.sub.L=Power losses
expended in the load as well as any system losses, and
P.sub.R=residual Power or energy stored in the load at the desired
output power, comprising an external power source for supplying
continuous input power, P.sub.IN, to the load to achieve the
desired output power, P.sub.O, (e.g. preheat) with an accompanying
residual power, P.sub.R, internal batteries that are automatically
coupled to drive the load only when the external power source is
disconnected; and a pulse time modulation circuit is coupled
between the internal batteries and the load for automatically
supplying Pulse Time Modulated power to the load to reduce the
input power, P.sub.IN, applied to the load to an amount sufficient
only to replace the power losses, P.sub.L, thereby just maintaining
the residual power, P.sub.R, equal to the desired output power,
P.sub.O, to conserve electrical power and prolong the life of the
internal batteries.
[0034] The present invention also relates to a method of extending
the life of batteries in a portable energy consuming device
comprising the steps of: coupling an external power source to the
device to cause the device load to reach a designated operating
condition, P.sub.O, without using the internal batteries (thereby
extending the battery life); supplying power, P.sub.IN, to the load
with the batteries only when the external power source is
disconnected from the device to make the device portable; and
coupling a circuit between the internal batteries and the load that
uses pulse time modulated pulses to automatically cause the input
power, P.sub.IN, to be supplied to the load in an amount
substantially equal to the device power losses, P.sub.L, sufficient
only to maintain the designated operating condition, P.sub.O,
thereby extending the life of the internal batteries.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] These and other more detailed objects of the present
invention will be disclosed more fully when taken in conjunction
with the following DETAILED DESCRIPTION OF THE DRAWINGS in which
like numerals represent like elements and in which:
[0036] FIG. 1 is generalized block diagram of the present
invention;
[0037] FIG. 2 is a block diagram illustrating the use of an
external power source only to bring an energy consuming device
(device) to a desired operating level and then using an internal
power source to just maintain the desired operating level and
further illustrating the option of using the external power source
to charge the internal power source (batteries) during the time
that the device is connected to the external power source;
[0038] FIG. 3 is a block diagram illustrating the external power
source connected to a device for bringing the device to a desired
operating level while simultaneously charging the internal
batteries of the device and, further, illustrating the mechanical
connector that disconnects the internal power source (batteries, in
this instance) from the load while the device is coupled to the
external power source;
[0039] FIG. 4 is a block diagram illustrating the energy consuming
device in its portable state with a control circuit operating an
electronic power switch to provide pulse time modulated power to
the load to only maintain the desired operating level of the
device.
[0040] FIG. 4 is a block diagram illustrating a base unit on which
a flat clothes iron is placed and illustrating the electrical
connections from the external power source to connectors on the
base unit for engaging corresponding connectors on the flat clothes
iron to both bring the flat clothes iron to a desired temperature
(operating level) while simultaneously charging the internal
batteries associated with the flat clothes iron;
[0041] FIG. 5 is a schematic diagram illustrating an energy
consuming device such as a hair curling iron mounted in a base unit
and illustrating the external electrical connections for both
preheating the device while simultaneously charging the device
internal batteries; and
[0042] FIG. 6 illustrates a control circuit shown in commonly
assigned co-pending provisional patent application Ser. No.
60/573,716 that can advantageously be used with the present
invention.
DETAILED DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1 is a generalized block diagram of an energy storage
device 10 of the instant invention. An energy storage element 12 is
shown as a resistive heating element 22 and a temperature sensor
89. In this generalized embodiment, a first power source 14, has AC
power applied from a wall socket in the normal fashion and provides
the AC on lines 16 and 16' to an AC/DC converter 30. The DC output
of the AC/DC converter 30 has a negative output to ground via
contacts 17 of the converter (which, as will be discussed
hereafter, may be a base unit in which the energy storage device 10
is placed when not in use) and a positive output of 8.4 volts in
the present example via contacts 19. The positive output voltage
via contacts 19 is coupled to contacts 23 of a double pole, double
throw switch 21. When switch 21 arms are in the position shown,
electrically engaging corresponding contacts 23, the energy storage
device is in the preheat condition. The positive voltage is coupled
on conductor 15 to the control circuit 70 (shown in detail in FIG.
6) that provides full power to the heating element 22 to preheat it
to a predetermined temperature. At the same time, the positive
voltage is coupled on conductor 27 to Lithium-Ion battery circuit
20 to charge up cells 29 and 31 to fill voltage. It will be
understood that circuit 20 may contain well-known circuits to limit
the charging voltage to a predetermined amount as well as to limit
the amount of current received by the battery cells 29, 31. Thus,
the battery power of the cells 29, 31 is conserved inasmuch as the
external power source (from the AC/DC converter 30) is used to
preheat the heating element 22.
[0044] When the device 10 is preheated to the proper temperature
(which may also be regulated with devices such as thermocouples and
the like), the switch arms 21 are moved to contacts 25 (either
manually or by the removal of the portable energy storage device
from a base) and power from the battery cells 29, 31 flows through
conductor 27 to switch arms 28 and conductor 15 to the control
circuit 70. The energy storage device is now portable and operates
from its internal battery cells 20, 31. This energy storage device
has a DC heating element (energy storage device) 22 that is
preheated by DC power from the AC/DC rectifier circuit 30 and then
operated as a portable device using DC power from its own internal
batteries.
[0045] An alternate embodiment of the energy storage device is
disclosed in FIG. 2 wherein is shown a block diagram 10
illustrating a second embodiment of the present invention. As can
be seen, an energy storage device 12 (hereinafter called "device")
has an external power source 14 removably coupled to the device 12
by means of conductors 16 to an AC load element 18 located within
the device to cause the device 12 to reach a desired operating
level. Then, when the desired operating level is reached, the
external power source 14 is disconnected from the device 12, device
12 becomes portable, and an internal power supply 20 is coupled to
its own DC load element 22 to just maintain the desired operating
level of the device 12.
[0046] Of course, the internal power source 20 may consist of the
internal batteries and a pulsing circuit as will be shown hereafter
to pulse the power of the internal batteries to the load. In such
case, the life of the internal batteries is extended as will be
disclosed hereafter.
[0047] Consider, as an example only, a hair curling iron. The iron
has a metal mass serving as the heated surface and it must be
raised to a sufficiently high temperature to enable it to be used.
This is accomplished in the prior art by the use of alternating
current (AC) and it takes several minutes to bring the metal mass
to a temperature sufficient for use in curling hair. Then when it
is used, the AC power cord must remain attached to keep the iron
hot.
[0048] It is highly desirable to make the curling iron portable and
eliminate the physical interference of the AC cord. However, if the
curling iron is made portable, no cord is attached and no AC is
used. Thus, the internal power source, without AC, must be placed
under a severe power drain to bring the device to the desired
operating level (in this example, temperature).
[0049] Thus, it can be seen with the block diagram of FIG. 2 that
if the device 12 is a hair curling iron, it can be heated to the
desired operating level or temperature with the external ac power
source 14. When the mass of the curling iron reaches the desired
operating level, or temperature, the AC cord 16 is disconnected
from the hair curling iron 12 in a well know manner as by means,
for example, of unplugging AC connectors from the device 12. An
internal power source, as will be shown hereafter, is then
automatically utilized to just maintain the desired operating level
or temperature.
[0050] In the generalized embodiment shown in FIG. 2, the external
AC power source utilizes and is connected to its own AC heating
element located within the device 12. Once the AC cord is
disconnected from the device 12, the internal DC power source 20 is
automatically connected to its own DC heating element 22, as will
be explained hereafter, to cause the device 12 to maintain its
desired temperature.
[0051] Also, as shown in FIG. 2, the external power source 14 may
be used to charge the internal power source 20 with the output of
an AC/DC converter by means of a second conductor 24 whenever the
device 12 is mounted in a base unit as will be shown hereafter.
[0052] Of course, the device 12 illustrated generally in FIG. 2
could represent any hair management device, in addition to a hair
curling iron, such as a blow dryer, that requires large amounts of
energy to get the device to the proper temperature. Device 12 in
FIG. 2 could also represent a flat clothes iron, a soldering gun, a
glue gun, a rotating mass, and the like. As used herein, the term
"energy storage device" is intended to include any of the energy
storage devices mentioned in this paragraph.
[0053] FIG. 3 is a schematic representation of a device 12 and
illustrating a generalized version of the electronics associated
therewith. The device 12 sits in a base unit (not shown for
simplicity of the drawings) that has a connector or jack 26 that
functions as set forth hereafter. The internal power source 20 in
FIG. 3 is coupled, through switch 28, to a DC heating element 22.
When the device 12 is to be brought to a desired operating level,
such as temperature, an external AC source 14 and connected power
cord 16 having on the end thereof an elongated connector 26 of any
well-known type in the art (connected to a base unit if desired as
shown in FIG. 5) can be inserted in a mating receptacle in the
energy storage device 12 in a well-known manner to connect the
external power source to an internally located AC load such as
heating element 18, for example only, on lines 32 and 34.
[0054] At the same time, if desired, the AC input can be connected
to an AC/DC converter 30, either internal or external (shown here
as internal) that can be used to charge the internal batteries 20
in a conventional manner as explained earlier.
[0055] When the AC heating element 18 causes the device 12, here a
temperature device, to reach the desired operating level (store the
desired temperature in this case), the energy storage device is
withdrawn from the mating receptacle connector 26, on a base unit
if desired, to make the device portable. When that happens, switch
28 returns to its normally closed position thereby connecting
internal power source 20 to its own DC load 22 on line 36. As will
be shown hereafter in relation to FIG. 4 and FIG. 6, a control
circuit 38 provides just sufficient energy from the internal power
source 20 to cause the device 12 to only maintain the desired
operating level.
[0056] The circuit shown schematically in FIG. 4 includes control
circuit 38 that is powered by the internal power source 20. When
the connector or elongated prong 26 (here represented by a phantom
line) is disconnected from device 12, switch 28 closes as explained
earlier.
[0057] An electronic switch 40, such as a power FET, is opened and
closed by the control circuit 38 with the use of Pulse Time
Modulated signals to modulate the power signal to load 22 from the
internal power source 20 to provide only sufficient power to
maintain the desired temperature. A light emitting diode (LED) 42
may be utilized, if desired, to let the user know that the control
circuit 38 is functioning.
[0058] The novel invention works well with any load requiring heavy
current to bring it to a desired operating level as explained
earlier. FIG. 5 illustrates a flat clothes iron 46 mounted on a
base unit 44 shown in cross-section. The flat iron 46 has a handle
47 that is sufficiently temperature insulated from the heated body
portion of flat iron 46 to enable a user to pick up and use the
heated flat iron 46.
[0059] The novel invention works well with any load requiring heavy
current to bring it to a desired operating level as explained
earlier. FIG. 5 illustrates a flat clothes iron 46 mounted on a
base unit 44 shown in cross-section. The flat iron 46 has a handle
47 that is sufficiently temperature insulated from the heated body
portion of flat iron 46 to enable a user to pick up and use the
heated flat iron 46.
[0060] It will be noted in FIG. 5 that an external power source 14
is coupled through cord 16 to a connector that is plugged into the
base unit in a well-known manner as explained previously. In this
example, external ac power is connected directly to connector 52 by
conductor 50 to preheat the iron when a switch on the base (not
shown here) is operated by a user when the user desires to use the
flat iron. At the same time, if desired, the internal power source
can be charged by the output from an AC/DC converter 48 on
connector 26. When the iron reaches the desired temperature as may
be shown in any well-known manner, the iron may be removed from
base unit 44 and thus becomes a portable iron. It should be noted
that while the AC/DC converter 48 is shown to be a part of the base
unit 44, it can be external to the base unit 44 if desired. Thus,
the flat iron 46 shown in FIG. 5 utilizes first and second heating
elements located internally of the flat iron 46. One heating
element is an AC heating element (to be used by the external power
source) and the other is a DC heating element (to be used by the
internal power source).
[0061] The flat iron 46 could, if desired, have only one heating
element and that is a DC heating element that would be used first
during the preheating on the base unit 44 and then, when the flat
iron 46 is disconnected from the base unit 44 to make the flat iron
portable, the single DC heating element would be connected to the
internal power source 20 to just maintain the desired
temperature.
[0062] As shown in FIG. 6, the base unit 44 has an AC/DC converter
48 associated therewith, either internal (as shown) or external to
the base unit 44. The device, then, uses the DC power source for
preheating a single DC heating element and when the device is
disconnected from the base unit 44 to make the device portable, the
internal DC source is coupled to the same single DC heating
element. Such a connection would be obvious to one skilled in the
art given the assignment of creating such connection and therefore
is neither shown nor explained here.
[0063] FIG. 7 illustrates a base unit 44 on which a hair curling
iron 64 (shown in phantom lines) could be mounted for preheating
and charging of its internal power supply. The internal power
supply may be batteries as is well known in the art. Again, an AC
power source, represented by electrical plug 14, is connected by
cord 16 to a connector 56 on the base unit 44 as explained earlier.
Also as explained earlier, the hair curling iron 64 could have a
single heating element for both preheating and portable operation.
As shown, however, a first heating element is used for preheating
with the external AC power source and a second heating element is
used for portable operation with the internal power source.
[0064] The AC input from the external power source is connected
directly to connector 62 on the base unit 44 while the DC power for
simultaneously charging the internal power source comes from an
AC/DC converter 58 whose DC output is coupled to connector 60. The
power cord 16 terminates at the base unit 44 with a connector 56.
Advantageously, connector 56 is identical to the connector 62 on
base unit 44. If, for any reason, the portable operation of the
device 64 is prohibited, the AC connector 56 can be plugged
directly into the device 64 where power is normally supplied by
connector 62. In such case, the hair curling iron 64 may
advantageously continue to be used as a conventional cord attached,
non-portable hair curling device.
[0065] In any use of batteries with a heating device, the batteries
must not be subject to heating from the heating elements. In a hair
curling iron, the batteries may be placed in a heat insulated
handle as is well-known in the art and which is heat insulated from
the heating element.
[0066] FIG. 8 is a schematic diagram of the electronic control
circuit for the novel invention herein that supplies only
sufficient Pulse Time Modulated energy to the device to replace
only load losses and to maintain the desired power output and
thereby conserve battery energy that would otherwise be wasted.
This diagram has been explained in detail in co-pending commonly
assigned provisional patent application Ser. No. 60/573,716
incorporated herein by reference in its entirety.
[0067] Briefly, however, unit 78 is a detector that senses the
desired operating level (e.g. a temperature sensor 80 as shown in
FIG. 8). Oscillator 94 generates, in this case, a sawtooth wave
output on line 96 that is coupled, along with the amplified
detector 78 signal on line 90 to a comparator 92. As long as the
amplitude of the amplified output of detector 78 on line 90 is
greater than the amplitude of the oscillator 94 output on line 96,
there is a constant output from the comparator 92 through resistor
100. This signal is coupled through switch 28 to the gate of power
FET 102 causing it to conduct and apply maximum power to the load
22.
[0068] However, as explained earlier, to save the internal
batteries, the device has, in this instance, an AC heating element
18 that is heated to bring the device to the desired operating
temperature. As can be seen in FIG. 8, the device is first heated
to the desired operating temperature with an external AC power
supply 44. The external power supply 44 is coupled to the energy
consuming device by means of, in this case, a male connector 26
that makes contact with points 75 and 76 (on line 16) to provide
power to the AC load 18 in the device. Switch 74 is a double pole,
single throw switch that first couples the external AC source to
the AC load heating element 18. In addition, the other half of
switch 74 couples the internal power supply (batteries) to the
control circuit described above. Because the control circuit uses
such little power, little drain is placed on the internal batteries
during the time the external power supply is bringing the device to
the desired operating temperature.
[0069] As explained earlier, the male connector, represented by
phantom line 26, physically opens switch 28 thus preventing the FET
from receiving any signal from the control circuit of the device
when the device is on the base unit. Thus no power is being
supplied to the DC load 22 during the time that the external AC
power source is heating the device to the desired operating
temperature with the use of AC heating element 18. When the AC
heating element or load 18 causes the device to reach the desired
temperature (which can be indicated in a well known manner by
illumination of an LED), the device is removed from its base unit
and the male connector 26 is removed from the portable energy
storage device closing switch 28 and allowing the signal from the
comparator 92 of the control circuit to be connected to the power
FET 102 which begins to apply power to the DC load 22. Because DC
load 22 is in physical proximity to the metal mass that has been
heated by the external power source 44, the DC load 22 is already
heated to the approximate desired operating temperature and the
power FET 102 now is Pulse Time Modulated by the control circuit to
provide just enough energy to DC load 22 to maintain the desired
operating temperature of the device.
[0070] An LED 103, if desired, may be coupled across FET 102 and
pulses with the pulsing of the FET to indicate to the user that the
control circuit is functioning.
[0071] Thus, there has been disclosed a novel improved portable
energy storage device that uses an external power source to cause
the device to reach a desired operating level and then when the
device is removed from its base, the external power source is
disconnected from the device and the internal power supply is then
automatically connected to a DC load to maintain the desired
operating level of the device. A control circuit is coupled between
the internal power source and the DC load to Pulse Time Modulate
the signal applied thereto to replace only load losses and to just
maintain the desired operating level. As explained earlier, the
desired operating level is intended to mean a desired operating
temperature, a desired operating rpm, or any other type of load
operating condition that has stored kinetic or potential energy
that will maintain the desired operating condition if sufficient
energy is provided to just replace the device losses.
[0072] While particular embodiments of the invention have been
shown and described in detail, it will be obvious to those skilled
in the art that changes and modifications of the present invention,
in its various embodiments, may be made without departing from the
spirit and scope of the invention. Other elements, steps, methods,
and techniques that are insubstantially different from those
described herein are also within the scope of the invention. Thus,
the scope of the invention should not be limited by the particular
embodiments described herein but should be defined by the appended
claims and equivalents thereof.
* * * * *