U.S. patent number 3,851,654 [Application Number 05/389,236] was granted by the patent office on 1974-12-03 for self contained electrochemical heat source.
This patent grant is currently assigned to Chem-E-Watt Corporation. Invention is credited to Frederick P. Kober.
United States Patent |
3,851,654 |
Kober |
December 3, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
SELF CONTAINED ELECTROCHEMICAL HEAT SOURCE
Abstract
An electrochemical heat source is described wherein an
electrochemical cell is provided with an electrical shorting member
which is connected to the anode and cathode electrodes of the cell
to enable the electric energy of the cell to be dissipated as heat.
A safe non-toxic electrochemical heater for hair waving, hot
compresses and similar uses is described wherein an anode in the
form of a foil of aluminum or aluminum alloys is spaced by a
non-conductive separator from an air depolarized activated carbon
electrode. An electrolyte of a solution of table salt is employed
to activate the heater. Various configurations and sandwich
structures are described.
Inventors: |
Kober; Frederick P. (Bayside,
NY) |
Assignee: |
Chem-E-Watt Corporation (Valley
Stream, NY)
|
Family
ID: |
26871631 |
Appl.
No.: |
05/389,236 |
Filed: |
August 17, 1973 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
175846 |
Aug 30, 1971 |
3774589 |
|
|
|
Current U.S.
Class: |
132/229; 219/200;
219/209; 392/311; 429/8 |
Current CPC
Class: |
A61F
7/03 (20130101); A45D 2/36 (20130101); A47J
36/30 (20130101); H01M 6/00 (20130101); H05B
3/00 (20130101); H01M 6/32 (20130101); A61F
2007/0062 (20130101); A61F 7/007 (20130101) |
Current International
Class: |
A45D
2/00 (20060101); A45D 2/36 (20060101); A47J
36/30 (20060101); A47J 36/24 (20060101); H01M
6/32 (20060101); H01M 6/00 (20060101); H01M
6/30 (20060101); H05B 3/00 (20060101); A61F
7/00 (20060101); A45d 002/12 () |
Field of
Search: |
;132/33,9,36.2,40 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: McNeil; G. E.
Attorney, Agent or Firm: St. Onge Mayers Steward &
Reens
Parent Case Text
This is a division of application Ser. No. 175,846, filed Aug. 30,
1971 now patent No. 3,774,589.
Claims
What is claimed is:
1. In a heating device for hair waving operations the combination
comprising
a shell formed of a hair heat protective material and having a cell
receiving recess,
an electrochemical cell shaped to fit within the recess in heat
transferring relationship with the shell, said electrochemical cell
including
an electrochemical cell structure formed of a generally thin
electrically conductive first member made of an electrochemically
active oxidizable material and a generally thin electrically
conductive second member made of an electrochemically active
non-metallic reducible material, said first and second members
having therebetween, said first and second members being further
selected for forming an electric heating current producing
electrochemical couple capable upon electrical interconnection of
the members of heating the electrochemical cell structure to a
temperature which is sufficiently high for forming said
self-contained heat source; and
a multiple of discrete electronically conductive elements extending
between the electrochemically active oxidizable first member and
the electrochemically active reducible second member for electrical
contact therewith, said electronically conductive elements being
spaced and selected to conduct an electric heating current between
the first oxidizable member and the second reducible member for a
uniform heating of the electrochemical cell structure during
activation of the electrochemical cell to dissipate electrical cell
energy within the shell to form heat for hair waving.
2. The heating device as claimed in claim 1, wherein the
electrochemical cell includes an air cathode electrode and an anode
foil electrode formed of a material selected from the group
consisting magnesium, magnesium alloys of aluminum and aluminum
alloys, a porous non-conductive separator located between the
electrodes, dry table salt enclosed between the electrodes, said
electrically conductive element interconnecting said electrodes to
short circuit the cell, whereby submersion of said electrochemical
cell in water activates the cell for generation of electricity and
heating of the short circuited cell.
3. The heating device as claimed in claim 2 wherein said foil anode
electrode is located in heat transferring relationship with the
shell and said air electrode faces inwardly from the shell for
exposure to air within the recess.
4. The heating device as claimed in claim 1 wherein said shell has
apertures extending to the recess and wherein said electrochemical
cell is apertured for electrolyte fluid communication between the
cell and the shell apertures.
Description
This invention relates to an electric heat source generally and
more specifically to a disposable self contained electrochemical
heat source for use in hair waving devices, hot compresses and
similar heating applications.
BACKGROUND OF THE INVENTION
Several heat sources for permanent wave setting of hair have been
proposed. In one such device an electric current is passed through
a resistance wire to heat a closely adjacent tress of hair. Another
device employs a solution in place of the resistance wire so that
the electric current may heat the solution which vaporizes and thus
both heats the tress of hair as well as provide fluid for hair
absorbtion. The U.S. Pat. No. to Durham et al. 2,118,177 and
Gentile, 2,055,099 are illustrative of such so-called
"electrolytic" heaters. Disadvantages with such electrolytic
heating devices reside in their need for a low voltage power supply
and an inherent danger if the low voltage electrodes are
inadvertantly shorted.
Still another heating device utilizes the heat generated during a
reaction of particular chemical materials. The U.S. Pat. to Pazul
No. 2,725,060 is exemplary of this type of heater. As described in
the Pazul patent, an aluminum foil is employed in a sandwich pad
structure with an absorbant cotton sheet which was impregnated with
dry stannous chloride. The structure is enclosed with aluminum
foils and is suitably pierced to enable water to be introduced for
activation of the pad. The water dissolves the stannous chloride
and the solution migrates into contact with the aluminum to
initiate a chemical reaction which generates heat. Many other
exothermic heating pads have been proposed and utilize different
materials; see for example U.S. Pat. Davis et al. No.
2,132,681.
The exothermic type of heating devices have disadvantages such as
potential explosions, noxious fumes, toxicity and corrosive
materials that may be injurious to persons. Control of the
exothermic reactions is more complicated as illustrated by the
reaction delaying chemicals described in the Pazul patent.
SUMMARY OF THE INVENTION
In a heating device in accordance with the invention an
electrochemical cell such as may be employed in a battery is
provided with a substantially integrally contained electrical
conductor which is connected between anode and cathode electrodes
of the cell to form a direct electrical short circuit. When the
cell is activated, it produces an electrochemical reaction which
converts chemical energy directly into electrical energy. The short
circuit provided by the electrical conductor enables the cell to
convert this electrical energy in a highly efficient manner into
heat.
The electrochemical heating device of this invention dispenses with
the need for external electrical power sources such as are required
by electrolytic heaters. In fact, the short circuited construction
of the electrochemical heating device provides a self contained
structure which is safe to handle and free of voltage hazards. The
internal voltage generated by the shorted electrochemical cell
functions as a driving force to maintain a generation of heat.
Hence, catalytic initiators, often employed in exothermic heating
pads, may be dispensed with and the hazards associated with
exothermic heaters are advantageously avoided.
An electrochemical heating device in accordance with the invention
may be formed of non-toxic materials in a safe structure and may be
advantageously stored for long time periods. For example, in one
sandwich structure embodiment for an electrochemical heating device
a cathode is formed of an activated carbon air electrode and the
anode is formed of a metallic foil of aluminum or alloys thereof. A
porous non-conductive separator is placed between the anode and
cathode and is impregnated with table salt to form a sodium
chloride aqueous electrolyte by the simple addition of water. The
anode and cathode are electrically shorted to one another by
employing metallic fasteners such as a staple applied through the
structure to contact both electrodes. An electrical short may also
be formed with a strip of the anode foil which is wrapped around
the separator to contact the cathode. This electrochemical heater
provides a safe and controllable source of heat with relatively
inexpensive components.
It is, therefore, an object of this invention to provide a
self-contained heating device which may be non-toxic and safe to
handle and can be advantageously controlled to provide heat for a
wide variety of applications such as permanent hair waving, body
heating compresses and the like.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of an electrochemical heating
device according to the invention.
FIG. 2 is a perspective underside view of an electrochemical
heating device in accordance with the invention.
FIG. 3 is a cross-section of the electrochemical device shown in
FIG. 2.
FIG. 4 is a cross-section of an electrochemical heater with another
embodiment for a short circuiting element in accordance with the
invention.
FIG. 5 is a cross-section of an electrochemical heating device with
still another embodiment for a short circuit element in accordance
with the invention.
FIG. 6 is a perspective of an electrochemical heating device in
accordance with the invention for use as a hair curler.
FIG. 7 is a perspective view of an electrochemical heating device
in accordance with the invention for heating of a medical hot
compress.
FIG. 8 is a perspective view of an electrochemical heating device
in accordance with the invention for heating of a food pan.
DESCRIPTION OF THE EMBODIMENTS
With reference to the schematic illustration of FIG. 1 an
electrochemical heating device 10 is shown formed of an anode 12, a
separator 14, a cathode 16 and an integrally contained shorting
member 18. The anode is electrochemically oxidizable substance
which is electrically conductive and may be made of commonly
available metals and their alloys such as for example magnesium,
Mg; tin, Sn; aluminum, Al; zinc, Zn; and iron, Fe.
The cathode 16 is an electrochemically reducible substance which is
conductive. The cathode need not itself be a reducible substance
but may provide an electrochemically active surface upon which
another material, e.g. oxygen on an activated carbon air electrode,
is reduced. Cathode materials may be formed of a wide variety of
substances such as for example manganese dioxide;
metadinitrobenzene; silver chloride, AgCl; silver oxide, AgO;
copper fluoride; copper chloride and air depolarized cathode
structures of the carbon and metal types.
The separator 14 is formed of a non-conductive porous material such
as cotton, felt or bibulous papers which enable ions of an
electrolyte to freely pass between the anode and cathode.
An electrolyte formed of an ionically conductive medium is placed
within the separator 14. The electrolyte may be an aqueous salt
solution such as table salt, NaCl or may be selected from a host of
many well known other electrolyte materials compatible with the
selected anode and cathode materials.
The shorting element 18 is formed of an electrical conductor which
is sized to support the short-circuiting current produced when the
electrochemical heating device is activated. The shorting element
further is integrally contained as part of the structure.
FIGS. 2 and 3 illustrate a sandwich structure for an
electrochemical heating device 10 in accordance with the invention
wherein an activated carbon air electrode 20 is employed as a
cathode. The air electrode 20 is formed in a manner that is well
known in the art. The air electrode 20 includes a screen 22 which
may be formed of a metal such as nickel or iron and serves as a
contacting electrode with a layer 22 of activated hydrophobic
carbon. A metallic electrically conductive anode foil 26, formed of
a chemically non-toxic material such as magnesium, aluminum, zinc
or their commercially available alloys, is wrapped around a cotton
separator layer 28 to contact the metal screen 22 with peripheral
edges 30. Fasteners 32, such as rivets or staples, are employed to
secure a connection between the anode 26 and cathode 20. The
resulting electrical shorting element is formed by both the
overlapping edges 30 and the fasteners 32 which thus also provide a
mechanical connection of the parts of the heater.
The separator layer 28 is impregnated with a dry salt such as
sodium chloride or alternatively the salt may be dispersed in dry
form between the anode and cathode. The anode foil 26 is suitably
apertured at a variety of areas 34 to enable water to penetrate the
space between the anode and cathode and form a salt
electrolyte.
Activation of the electrochemical heater 10 involves the simple
step of applying water. As soon as the water has formed an
electrolyte solution with the salt an electrochemical cell is
formed whose output voltage is determined by the materials employed
for the anode and cathode. The shorting path provided by the edges
30 and fasteners 32 then enables the electrical energy to be
converted to thermal energy at an efficiency approaching 100
percent.
The thermal power generated is directly proportional to the square
of the current and the internal resistance of the cell. One may
thus control the current flow by selecting the thickness of the
separator 28 and control the thermal power. The current flow also
may be controlled by varying the resistance or cross-sectional area
of the shorting element. For example, as shown in FIG. 3, the
shorting path can be determined solely by the number and types of
fasteners 32 (e.g. staples) which electrically interconnect the
anode 26 to the cathode 20 without the use of an overlapping edge
30 shown in FIG. 3. Alternatively, a shorting element 18 such as
shown in FIG. 5 may be used. In the structure of an electrochemical
heater 10 as shown in FIG. 5 a peripheral edge 36 of the anode 26
is brought in registration with a correspondingly shaped edge 38 of
the screen 22 and connected together either with a fastener 32 or
spotwelds or other convenient means.
In the structure of FIG. 5 the contact of peripheral edges 36 and
38 provide an electrical short circuit of the cell. The electrical
shorting conductor may thus be conveniently formed into an integral
part of a self contained electrochemical heater and provides an
efficient conversion of the chemical energy into heat.
The electrochemical heating device exhibits an advantageous
flexibility in that it may be conveniently adapted to a variety of
shapes. The thickness of the cell can be reduced to form a flexible
structure that can fit in the recess of a hair heat protective
cylinder 42 as shown in FIG. 6 or adapt to the contours of a body
area for a hot compress 43 as shown in FIG. 7.
The hair heat protective cylinder 42 is formed of a plastic
material and is provided with apertures 44 extending into a
centrally located recess 40 into which an electrochemical cell such
as shown in FIGS. 2 and 3 is placed. The aluminum foil anode
electrode 26 is located adjacent to the cylinder wall 46 to enable
the air electrode 20 to remain exposed to air. After insertion of
the electrochemical heater 10 into recess 40 and submersion into
water the heat is transferred through the cylinder wall 46 onto a
person's hair that is wrapped around the cylinder to receive a
permanent wave. Apertures 44 serve to enable the water electrolyte
to provide water for hair absorbtion. After the chemical energy has
been dissipated the electrochemical heater 10 may be removed from
recess 40 and replaced by another so that the cylinder 42 can be
reused.
The hot compress 43 shown in FIG. 7 utilizes a cotton or other
suitable water absorbant material 48 which is placed in contact
with the body area to be treated (a forearm in FIG. 7). A flexible
electrochemical heater 10 is located over the cotton compress 48
which may have been previously wetted. The electrochemical heater
also may have been filled with liquid electrolyte or the water for
formation of an electrolyte can be absorbed from the wetted cotton
compress 48. A suitable string or other fastening device (not
shown) may be employed to hold the hot compress 43 in place over
the body area to be treated. The water electrolyte advantageously
prevents overheating since excessive temperatures would cause a
boiling off of the water. The aluminum or aluminum alloy anode and
activated carbon depolarized air cathode electrode and table salt
electrolyte form a non-toxic safe selfcontained localized heater
suitable for such medical purposes.
In the arrangement shown in FIG. 8 an electrochemical heater 10 of
enlarged surface area is shown removably mounted to the bottom 51
of a food pan 50. Adjustable clips 52 retain the heater 10 which is
of circular shape for adequate heating of the pan 50.
The electrochemical heater 10 shown in FIG. 8 may be such as shown
in FIGS. 2 and 3 with an overlapping anode edge 30. The anode
electrode is placed adjacent to the bottom 51 of the pan 50 while
the air cathode electrode 20 is exposed to air even when the pan 50
rests on clips 52. After the heater 10 is mounted to the pan, the
latter's bottom 51 is quickly dipped into water to wet the
electrochemical heater 10 which is then activated to commence
heating of the pan 50 and food placed therein.
The electrochemical heater as thus described may take a variety of
forms. For example the electrochemical heater may be formed in an
enclosed structure which includes an anode and a cathode and a
liquid electrolyte. The anode and cathode may be externally
accessible for connection to a separate shorting member. When the
shorting member is connected in contact between the anode and
cathode electrochemical heating is commenced in the manner as
described with respect to the previous embodiments.
Having thus described an electrochemical heater its many advantages
may be appreciated. It may be formed of non-toxic nonhazardous
materials suitable for heating applications in medical or food
related fields. The electrochemical heater may be stored for long
time periods and can be readily activated by the simple addition of
water where a dry electrolyte material is enclosed. The aluminum or
aluminum alloy foil anode and air cathode electrochemical heater
may be activated with table salt solution. The electrochemical
heater may be controlled by sizing as desired. For example, in a
thin sandwich structure form the heater can be cut with scissors to
a desired size and shape. The amount of heat produced can be
controlled by limiting the quantity of water supplied to the porous
separator. A wide variety of materials may be employed in selecting
a desired electrochemical heater.
* * * * *