Note: Descriptions are shown in the official language in which they were submitted.
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HEATED SHOE INSOLE REMOTE CONTROL SYSTEMS
FIELD OF THE INVENTION
[0001] The present invention relates to a remotely controlled heated insole
for
footwear and to an improved method of control of such heated insoles that
provides a
more reliable means of ensuring that the temperature desired by the user is
realized.
BRIEF DESCRIPTION OF THE INVENTION
[0002] The present invention is directed to heating insoles of footwear, and
improving the ability to realize desired temperatures through wireless control
signals.
Heated insoles are intended to aid a user in withstanding cold weather by
providing
supplementary heat in the case where normal body heating is not enough or when
additional heat is desired to be more comfortable. When an extremity of the
body starts
to become cold, the body's natural physiological response of vasoconstriction
occurs in
which the nervous system restricts blood flow to the cold extremity in an
effort to keep
the rest of the body warm. It is well known that frostbite and other cold
related injuries
occur first in fingers and toes due to vasoconstriction and keeping these
extremities
warm will help insure survival or at minimum a more pleasurable outdoor
experience.
[0003] Heated insoles are a key component to preventing injury in cold weather
and are well known to hunters and outdoorsmen as standard survival gear while
in the
woods or forest. A problem exists however in the control of such insoles as
often the
insole temperature needs to be adjusted to accommodate different conditions
and
comfort levels. Standard temperature adjustment methods require the user needs
to
remove his or her boot to gain access to the Insole in order to make desired
adjustments. Not only is this procedure time consuming but removing the user's
foot
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from the boot to gain access to the insole exposes the foot to the cold
conditions. This
adjustment procedure undoubtedly lowers the foot temperature even further
thereby
further increasing risk or injury.
[0004] An improved method of control has been developed however utilizing a
hand held remote control system which employs a transmitter unit external to
the insole
and a receiver unit located within the insole assembly inside the boot. The
desired heat
adjustment is then performed by the user selecting a heat setting on the hand
held
remote unit which is then wirelessly transmitted to the receiver unit located
within the
heated insole assembly. Although this improved method of control is an
improvement,
the design requirements for a proper fitting heated insole yields conditions
not optimum
for wireless control as will be pointed out in the following discussion.
[0005] Heated insoles are placed in a shoe with its bottom surface against the
bottom of the shoe and the upper surface against the user's foot when in use.
Antenna
placement within the insole is positioned parallel to the ground surface and
also to the
foot placed above it. A problem exists in the prior art however in which this
restrictive
antenna positioning tends to prohibit the reception of information transmitted
from the
hand held unit to the receiver unit due to the signal grounding effect
produced by the
earth's surface on the bottom and the user's foot on top of the antenna. This
grounding
effect is often severe enough that it inhibits information from the
transmitter to the
receiver unit, therefore preventing any heating adjustments to be made.
[0006] Additionally, the location of the RF receiver, inside shoes, adjacent
to the
ground requires special consideration to overcome signal loss. Prior art radio
controlled
insoles include the wire antenna along the midline of the insole. This has
been
problematic because signal strength is affected. The inventors realized that
much of the
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,
,
transmitted signal is blocked by the ground from reaching the receiver antenna
located
in the insole. The foot and body of the wearer also tend to block the signal.
One
improvement of this invention for the receiver antenna is to locate it more
advantageously for signal reception, for instance, near the outer margin of
the insole.
Reception is materially improved with such an antenna.
[0007] The present invention includes a heated insole device that uses radio
frequency communication with an improved transmission system to control the
desired
insole temperature. The present invention uses a standard frequency of 433
Megahertz
but may be used with other frequencies, such as the common 2.4 Gigahertz.
[0008] As described above, the manufacturing of an insole product requires
that
the device itself be relatively flat and fit within a standard shoe or boot.
This
requirement forces the necessary power source, control methods and
communication
means to all exist within the confines of the shoe and lie in a flat plane
parallel to the
earth's surface. Although this space limitation is achievable with good design
practice,
radio communication suffers largely due to the horizontal orientation of the
antenna, its
proximity to the earth and the person standing above it. Furthermore,
transmission at
the frequencies described above is dictated by governing authorities to be a
limited
transmission of a just a few seconds per hour, so the notion of continuous
transmission,
if even in the power budget, would be prohibited.
[0009] The present invention also discloses a system and method of
communication that helps to ensure that user commands are more effectively
transmitted by providing a plurality of transmissions at specific spaced
intervals of time.
By providing discrete, timed transmissions after the user temperature control
has been
initiated, the probability of transmissions coinciding with the user taking a
step and lifting
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his foot off the ground is increased. The timed control signal may be
initiated by the
remote or may be controlled by a microprocessor within the insole. With the
foot off the
ground, the distance between the horizontally placed antenna within the insole
and the
earth's surface is greatly increased, thus increasing the reception range for
the insole.
A secondary action that occurs while a foot is in the air is that the pressure
of the
person wearing the shoe is relieved from the insole, decompressing the foam
some
measurable amount between the antenna and the person. This decompression
although small, tends to increase the transmission success thus providing a
better user
experience.
[0010] For example, it is well known that an adult person walks at a rate of
three
miles per hour, which equates to four feet per second with a stride length of
about
eighteen inches. This stride and pace suggests approximately 2,6 steps be
taken every
second.
[0011] Since bipedal humans alternate feet while walking, this suggests that
each foot is lifted off the ground every 1.3 seconds or approximately once per
second.
[0012] Knowing that each foot is off the ground once per second for almost a
second, allows more robust communication by providing transmissions that occur
while
the foot position is in the air and not on the ground surface. Transmissions
every half
second will insure some of the broadcasted signal will be simultaneous with
the foot
being in the air, thus delivering the intended command to the insole device.
Other time
periods may be chosen in accordance with prevailing governmental regulation.
[0013] For skiers or snowboarders who use this invention, the position of the
foot
also shifts from purely horizontal to some vertical orientation, such as when
a skier uses
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,
edges or a boarder shifts positions. Still further, the heating operation may
occur while
the user is in a lift chair which also alters the orientation of the sole.
[0014] Transmitting the sequence of coded signals periodically for a short
period
of time after the initiation of the process to heat the insole increases the
ability of the
user to more effectively communicate the heating instructions to the insole.
[0015] The instant invention includes a battery powered electrically heated
pair
of insoles that are in radio communication with a key fob R/F transmitter. The
battery is
a lithium ion polymer battery and is provided with a self-contained
conventional
protective circuit. The transmitter sends out an encoded signal to be received
and
decoded by a unique pair of insoles. The insole has an on/off switch. This
switch may
be placed in the on position before the insole is placed inside the shoe.
[0016] When the switch is placed in the on position, the insole does not
produce
heat, but the R/F system in the insole is ready to receive commands from the
key fob
transmitter. Each insole has an on/off switch and may have a unique code
permitting
selected insoles to be heated. When both switches are on, both insoles will
respond to
the key fob transmitter, The user may utilize the key fob transmitter to
select among; no
heat, medium heat, and high heat by pressing the appropriate button on the key
fob
transmitter. Settings other than discrete may be used.
[0017] When a heat setting is selected on the key fob transmitter, the RF
receiver in the insole detects the signal and, if intended for a specific
insole, activates
the process therein. The microprocessor senses the temperature near the
heater, and
if the temperature is too low for the selected setting, current flows from the
battery to the
heater until a thermistor reaches a predetermined temperature. The thermistor
generates a signal which is sent to the microprocessor. The microprocessor
controls
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the flow of current to achieve and maintain the desired temperature until the
user
selects another setting. Other methods of controlling the heat in the insole
may be
employed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Fig. 1 is a block diagram of the transmitter unit;
[00191 Fig. 2 is a block diagram of the electronic circuit within the insole;
and
[0020] Fig. 3 A and 3B are partial sectional views of the insole showing the
location of the antenna in the present invention and in the prior art.
DETAILED DESCRIPTION
[0021] Fig. 1 is a block diagram showing the transmitter 10 of this invention.
The
transmitter comprises an integrated circuit S14010 which is connected to a
plurality of
push buttons 12, 14 and 16. The push buttons generate signals to cause high,
medium
and no heat conditions, respectively, to be generated within the insole. The
user
selects a push button to be activated in order to control the temperature
within the
insole.
[0022] An LED 18 may be connected to the transmitter to indicate that the
transmitter is transmitting and/or to indicate that the transmitter is on and
capable of
transmitting. An antenna 19 connected to the transmitter wirelessly transmits
electronic
signals generated in transmitter 10 to the electrical circuit within the
insole.
[0023] The transmitter 10 decodes the user command by determining which of
the push buttons is selected, and the transmitter provides a burst of four
packets of
information or electrical signals with each packet consisting of an address
and data.
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The packet length, by example, is 120 ms in length and the entire four packets
takes
approximately 512 ms to transmit. To ensure the command is received properly,
the
four packet sequence is repeated every 15 seconds over the next minute for a
total of
20 packets. This is within current FCC regulations.
[0024] Referring to Fig. 2, there is shown an electrical circuit located
within the
insole. Transmitted data packets are received and decoded through receiver 24
and
connected to microcontroller 26. The decoded signal is sent to the
microcontroller for
processing. which creates a control signal for heater control 28 to achieve
the desired
temperature condition for the insole. Additionally, the address data
identifies the insole
to be controlled. The heater control 28 is connected to heater assembly 30
located
within the insole to heat the insole to a desired temperature. The heater
assembly also
includes a temperature sensing device such as a thermistor to determine the
real time
temperature of the heated insole to determine if further heating is required
under control
of microcontroller 26.
[0025j The microcontroller 26 and heater assembly 30 are powered by a 4.2 volt
lithium ion polymer battery 32 having an internal safety circuit 34,
[0026] The lithium battery 32 is recharged by using an external DC charger 22
connected to input jacks 36 located within the insole. The charging is thus
controlled
outside of the insoles. A voltage limiter 38 is connected to the output of the
external
charging input to ensure that the voltage supplied to recharge battery 32 is
maintained
below a certain level. Battery charging is achieved by using the external
charger to
control voltage and current to the batteries, and the voltage limiter 38
provides fine
voltage control to optimize battery charging. An LED 23 is provided with the
external
DC charger 22 to display the battery status so it can be determined when the
battery
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,
,
has been sufficiently charged, and the external charger may be unplugged from
the
insoles. A three volt regulator circuit 42 is provided to ensure that the
microcontroller
and heater assembly properly operate. The control circuit for the system shown
in Fig.
2 includes voltage regulator 42 to control the voltage at microcontroller 36.
[0027] Locating the protective circuit 34 within the battery is an improvement
over having a protective circuit outside of the lithium battery. Providing the
protective
circuit within the lithium battery is important because if the battery leads
short circuit, a
hazard will be prevented by having the protective circuit therein. If the
protective circuit
is remote from the lithium battery, damage from such short circuit to the
battery will not
be prevented.
[0028] In normal use, the user sets the on/off switch 44 to the on position in
the
insole to allow the battery voltage to control the electronic circuitry
therein. The
microcontroller 26 receives a command signal from RF receiver 24 and decodes
the
information to see if the unique address matches that of the insole. If such a
match is
found, the microcontroller then determines from the command signal the heat
setting
which is desired. Once such heat setting is decoded, the microcontroller 26
then
commands the control circuit 28 to turn on the heater and maintain a desired
heating set
point. This continues until the user switches the on/off switch to off or the
battery power
is exhausted. Additionally, there is a heat control (No Heat) in the
transmitter which
also can turn off the heating unit.
[0029] The instant invention includes a battery powered electrically heated
pair
of insoles that are in radio communication with the key fob R/F transmitter 8
(see Fig.
1). The transmitter 10 sends out an encoded signal that may be received and
decoded
by a unique pair of insoles. When the switch in the insole is on, the insole
does not
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produce heat, but the R/F system in the insole is ready to receive commands
from the
key fob transmitter. Each insole has its own on/off switch. When both switches
are on,
both insoles may respond to the key fob transmitter depending on the address
data.
The user may utilize the key fob transmitter 8 to select among; no heat,
medium heat,
and high heat by pressing the appropriate button on the key fob transmitter 8.
[0030] When a heat setting is selected on the key fob transmitter 8, the RF
receiver 24 in the insole detects the signal and activates microprocessor 26.
The
microprocessor 26 senses the state of a temperature measuring thermistor
located near
the heater, and if the temperature is too low for the selected setting,
current flows from
the battery 32 to the heater 30 until the thermistor reaches a desired
temperature.
Then, the microprocessor 26 reduces the flow of current to keep the
predetermined
temperature. The temperature is maintained until the user selects another
setting,
[0031] The location of the RF receiver, inside shoes, adjacent to the ground
requires special consideration to overcome signal loss. Prior art radio
controlled insoles
locate the wire antenna 40 along the midline of the insole (see Fig. 3b). This
has been
problematic because signal strength is not sufficient. Much of the transmitted
signal is
blocked by the ground from reaching the receiver antenna located in the
insole. The
foot and body of the wearer also tend to block the signal. The receiver
antenna 42 of
this invention is located near the outer margin of the insole (see Fig. 3a).
[0032] When the user is ready to recharge the batteries, the insoles may be
removed from the shoes and the switches are placed in the off position. In the
alternative, the charging jacks may be available from outside the footwear by
suitable
protective waterproofing of such jacks,
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[0033] It should be understood that the preferred embodiment was described to
provide the best illustration of the principles of the invention and its
practical application
to thereby enable one of ordinary skill in the art to utilize the invention in
various
embodiments and with various modifications as are suited to the particular use
contemplated. All such modifications and variations are within the scope of
the
invention as determined by the appended claims when interpreted in accordance
with
the breadth to which they are fairly legally and equitably entitled.
