Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TITLE OF THE INVENTION
OXYGENIHYDROGEN GENEIRATOR
FOR INTERNAL COMBUSTION ENGINES
FIELD OF THE INVENTION
This invention relates to electrolytic oxygen/hydrogen generators and to an
anode arrangement for use in such generators.
BACKGROUND OF THE INVENTION
It has been proposed to introduce a proportion of hydrogen andlor oxygen
into a fuel mixture for burning in an internal combustion engine, in order to
increase the efficiency of burning. The intended result is reduced noxious
emissions to the environment, reduced engine maintenance and reduced fuel
costs.
To date many devices have been proposed for this purpose, but none has
come into widespread use.
PRIOR ART
Applicant is aware of the following patents and published applications which
pertain to this subject matter:
U.S. Patent No. 4,442,801, to Glynn, et al.;
U.S. Patent No. 4,392,937, to Schmitt, et al.;
U.S. Patent No. 4,028,208, to Giacopeli;
U.S. Patent No. 4;369,737, to Sanders, et al.; and
Canadian Patent No. 1,113,037, to Boulton.
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BRIEF SUMMARY OF THE INVENTION
The invention provides an oxygen/hydrogen generator which includes
improved components in a novel structural combination.
In one embodiment the invention provides an anode arrangement for use in
a hydrolysis cell for generating hydrogen and oxygen gases, the arrangement
comprising a stack of perforated electrically conducting wafers, vertically
spaced
from each other, and a connector for connecting each wafer to an electrical
circuit.
In a further embodiment there is provided a hydrolysis cell for generating
hydrogen and oxygen and which comprises a casing which is at least in part
electrically conducting and comprises a cathode, and has within it an anode
arrangement as described above. The cell includes means for the introduction
of
make-up liquid and for removing produced gas.
In a further embodiment there is provided a hydrogen and oxygen generator
comprising an electrolytic cell having a casing, an anode, a cathode, an inlet
and
first and second outlets. A liquid make-up system i s provided which comprises
a
liquid reservoir connected to the inlet, a vacuum pump connected to the second
outlet and air pressure equalization means for the reservoir and the inlet
tubing.
When the vacuum pump is activated, make-up water is drawn into the cell from
the
reservoir and the air pressure equalization means equalizes air pressure in
the
make-up system to atmospheric pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other advantages of the invention will become apparent upon
reading the following detailed description and upon referring to the drawings
in
which:
Figure 1 is a schematic drawing of an oxygen/hydrogen generator
according to the invention;
Figure 2 is a plan view of a wafer for use in the invention;
Figure 3 is a plan view of a second wafer for use in the invention;
Figure 4 is a cross-section through an elecarolytic cell according to the
invention;
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Figure 5 is an exploded view of components of the anode arrangement for
the cell of Figure 4;
Figure 6 is an assembled anode arrangement according to the invention;
Figure 7 is a perspective view of a separator disc for upper and lower parts
of the cell of Figure 4;
Figure 8 is a plan view of the top of cell of Figure 4;
Figure 9 is a schematic drawing of an injection arrangement for an internal
combustion engine;
Figure 10 illustrates a physical arrangement of some of the components of
the generator according to the invention;
Figure 11 illustrates a housing for the front of the arrangement of Figure 10;
Figure 12 is a schematic drawing of a level aensing device for use in the
invention;
Figure 13 is a nozzle for use for gas injection in the invention; and
Figure 14 is a schematic drawing of a slightly modified generator according
to the invention.
While the invention will be described in conjunction with illustrated
embodiments, it will be understood that it is not intended to limit the
invention to
such embodiments. On the contrary, it is intend'~ed to cover all alternatives,
modifications and equivalents as may be included within the spirit and scope
of the
invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
In the following description, similar features in the drawings have been
given similar reference numerals.
The generator 10 comprises a cell 12 having a liquid inlet 14 and a gas
outlet 16. Make-up liquid is provided by liquid make-up system 18.
The cell 12 comprises lower chamber 20 and upper chamber 22, separated
by separator disc 24.
Lower chamber 20 includes a base disc or bottom 26.
Lower chamber 20 of electrolytic cell 12 contains anode 28. Anode 28
comprises a stack 30 of wafers 32 and 33. Wafer:; 32 and 33 are mounted on
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connector 34 at openings 35 and are vertically spaced on the connector by
conductive washers 36. Lower end 38 of connector 34 is fixed to an insulating
disc 40, and is spaced by insulating discs 40 and 42 from base 26 of casing 44
of
lower chamber 20. As best illustrated in Figures 4 to 6, the stack 30 may be
stabilized by support rods 46 at openings 47, rods ~46 fixed to insulating
disc 40
and to upper plate 48. Each wafer 32 and 33 is separated from adjacent wafers
along support rods 46 by conductive washers 50.
Stack 30 is divided into an upper section 52 and a lower section 54. The
wafers 33 of upper section 52 include an opening 56 to accommodate level
sensing device 58. Opening 56 is absent from wafers 32 of lower section 54.
Wafers 32 may comprise expanded stainless; steel discs or the like, but
stainless steel mesh has been found to be particularly suitable. This mesh may
have the appearance of ordinary door and window s<;reens. Typically the
screens
may be less than one millimetre in thickness.
Separator disc 24, as illustrated in Figure 7, includes apertures 60 and 62 to
accommodate connector 34 and level sensing devicE: 58 respectively. Connector
34 and level sensing device 58 are sealed against leakage at apertures 60 and
62.
Separator disc 24 separates casing 44 of lower chamber 20 from casing 64
of upper chamber 22 and acts as a seal between the two. Casing 44 is
electrically
connected to the electrolysis circuit through connector 45. The connection is
to
the grounding circuit of the vehicle and thus enables casing 44 to comprise
the
cathode.
Figure 7 also illustrates the use of filters in the: separator disc 24 to
prevent
egress from lower chamber 20 of moisture and of electrolyte. Thus, apertures
66,
68 and 70 are provided in separator disc 24. As illustrated, the apertures
contain,
as filters, porous metal alloy plates. One suitablE: porosity range is 5 to 50
microns. A typical material is that sold by Metal Supplies Online, Inc. under
the
designation "Super Alloy HASTELLOY~ C276 alloy".
Upper chamber 22 functions as a gas manifold and cooling chamber for
gases produced in the electrolysis process.
Top 72 of upper chamber 22 contains a number of apertures. Aperture 74
provides sealing and insulating engagement for upper' end 76 of connector 34.
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Aperture 78 provides sealing engagement for upper end 80 of level sensing
device 58.
Aperture 82 connects to gas outlet conduit 16 i:hrough gas outlet valve 84.
Aperture 86 leads to pressure regulator 88. Pressure regulator 88 is
adjustable over an appropriate range of pressure, typically 10 to 225 psi.
Outlet
valve 84 is controlled by pressure regulator 88 through microprocessor 152.
While
operating pressure for the cell will vary with specific applications, a
typical value
for a turbo charged diesel engine would be 50 psi. This is well above normal
turbo
diesel operating pressures and avoids any backpressure problems due to
malfunction.
Aperture 90 connects to liquid inlet conduit 14 which is described in detail
later in this description.
Aperture 92 connects to vacuum pump 94, the operation of which is also
described later.
Finally, aperture 96 connects to a rupture disc 98, which acts as a final
safety device. Typically, the rupture disc will blow at a pressure suitably
above the
cell operating pressure; e.g. 70 psi, or suitably in a range of 50 to 150 psi.
The seals may be comprised of teflon throughout.
With reference to gas outlet 16, a conduit 17 leads from outlet 16 at the top
72 of cell 12 through a first run 100 to a moisture collector 102. From
collector
102, a second run 104 leads to an injector 106 in an internal combustion
engine
fuel supply line. Moisture collector 102 is provided with an electrically
operated
drain valve 108 to drain collected moisture. The valve may operate on a timing
sequence such that, for example, the valve would operate for a very brief
period
every half hour. Pressure in the line would expel cOIIE:C$ed moisture, but the
timing
sequence is sufficiently short as not to have any material effect on system
pressure. Typical operating time may be 0.5 seconds for each'/2 hour cycle.
It is of note that first run 100 of conduit 17 may run from the top of the
cell
12 in a direction toward the bottom of the cell 12, with the moisture
collector 102
located at the bottom of the run which may be near the bottom of generator 10.
The second run 104 then leads back to an upper part of the generator 10 and
hence out of the generator and toward the engine. The vertical drop over the
two
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runs 100 and 104 then influences moisture condensing in the runs to flow down
into collector 102.
Downstream of second run 104 the conduit '17 may include an additional
moisture removing filter 110. This may be a silica gel filled filter.
Conduit 17 may also include a low pressure detector 112.
Conduit 17 may enter an internal combustion engine system at a
convenient point. This point: of entry may be in an air inlet to the engine
and may
be downstream of a turbo charger. With reference to Figures 9 and 13, an
injection nozzle 114 may comprise an angled fixture 115 which enters engine
fuel
supply line 116 at a suitable point, and barb 117 which discharges in a
direction
parallel to air flow through the line. The discharge point may be on the
centre line
of the air supply line 116.
The electrolyte may comprise a solution of potassium hydroxide (K~H) at a
suitable strength. The water part of the solution will slowly be used up in
the
production of hydrogen and oxygen. Accordingly, it is necessary from time to
time
to add make-up water to the electrolyte.
Thus, Figure 1 also illustrates a liquid make-up system 18 for cell 12. This
system includes a casing 120 and a base 122. Casing 120 includes a mounting
124 for a liquid supply bottle 126. Bottle 126 opens into a reservoir 128 in
base
122.
Liquid inlet conduit 15 leads from reservoir 128 in base 122 to the cell inlet
14. Conduit 15 may include a heater 130. Heater 130 may include a temperature
sensor 131 to detect a preset low temperature and to switch on heater 130. A
typical such low temperature preset would be 4°C:
Conduit 14 may also be equipped with a solenoid valve 132 for purposes of
pressure equalization in the liquid make-up system.
The reservoir 128 includes a level detector 134 and temperature sensor
136, and a resistance heater 137.
Casing 120 may include an incandescent bulb 138. The temperature
sensor 136 may act at a predetermined low temperature to switch on heater 137
and/or bulb 138. A typical such low temperature preset would be 4°C.
A door 140 on casing 120 may incorporate a cutter (not shown) to pierce
the bottom of bottle 126 when the door is closed on thE> bottle.
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As well, base 122 may include a cutter (not shown) to pierce a seal on
bottle 126 when the bottle is inserted into the base.
Liquid make-up system 18 includes a vacuurn system 142. The vacuum
system may comprise the vacuum conduit 144 leading from aperture 92 through
solenoid valve 146 to vacuum pump 94. Conduit 144 may also include filter 148,
which may be a silica gel filter on conduit 144.
The level sensing device 58 also comprises a part of the liquid make-up
system 18.
Level sensing device 58 may comprise a cap<~citive float detection system
in which each measuring point combines a float and a capacitive sensing
system.
Thus, with reference to Figure 12, the device 58 is shown schematically
positioned
in cell 12.
The level sensing device 58 comprises a probe 160 having four switch
points 162. Each switch paint includes a capacitive sensing system 164 which
measures the capacitance of the solution between probe 160 and grounded wall
44 of cell 12. Each of floats 166, when in proximity to a respective
capacitive
system 164, turns on the respective system to recognize the presence of the
float.
A signal is then transmitted to the microprocessor 152. Each float is free to
travel
at the electrolyte surface, between positions just above and just below its
respective capacitive system, and will be recognized only when at the level of
the
capacitive system.
In one embodiment the capacitive system includes a sensitive amplifier 168
capable of differentiating foam and liquid. Hence, a false reading would not
be
accepted, should a float ride up on a foam layer.
As discussed below in the description of the operation of the cell, the levels
sensed preferably comprise "full" and "low" levels, bounding the normal
operating
range; and "high shutdown" and "low shutdown" levels, which are assumed to be
triggered by a malfunction and thus comprise safety levels.
The generator 10 includes a casing 150 and may be provided with a cooling
system to bring ambient air into casing 150 and expel heated air from the
casing.
The cooling system may comprise one or more cooling fans 149 in a housing 151.
Generator 10 includes a microprocessor 152, which is electrically
connected to at least one power supply 154 and to the various described
sensors
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and valves to control the generator. Power supply 154 is also connected to the
anode and cathode to power the cell. The power supply 154 receives power from
the internal combustion engine electrical system. Power supply 154 is
typically
operating in the range, or adjustable over the range, of 12 volts120 amps to
2.5
volts1120 amps.
In one embodiment the power supply operates at full power at 120 amps.
In another embodiment the power supply is controlled by microprocessor
152 to operate over the range specified above, responsive to engine load.
In operation, the cell 12 will be filled to a "full" level with a suitable
electrolyte solution. On ignition of the internal combustion engine to which
the
generator is connected, the microprocessor 152 will activate the electrical
circuitry
causing current to flow through the cell and liberating hydrogen and oxygen in
lower chamber 20 of cell 12.
Once the pressure in the cell reaches the operating pressure, as detected
in the pressure regulating valve 88, the valve will open and permit the flow
of gas
to the internal combustion engine.
Operation will continue in tandem with operation of the engine, and the
electrolyte level in cell 12 will slowly decrease as liquid is broken down in
the
electrolysis process to yield the product gas mixture. When the level sensing
device 58 detects that the level of electrolyte in cell 12 has reached a "low"
level,
this information will be transmitted to the microprocessor 152, and the
microprocessor will shut down operation of the cell and initiate the liquid
make-up
system 18. At all times during operation the system 18 will include bottle 126
of
make-up liquid, normally distilled water.
The vacuum pump will then be switched on and solenoid valve 146 opened
to reduce pressure in cell 12. Solenoid valve 147 in liquid inset conduit 14
will then
be opened to permit the flow of liquid from bottle 126 to cell 12. Once the
level of
electrolyte again reaches the "full" level, the vacuum pump will be shut down
and
solenoid valve 147 also shut down to prevent furthE:r inflow of make-up
liquid.
Normally, a typical vacuum pump might operate for less than 20 seconds per
fill
cycle. The microprocessor will then restart the generator.
Various safety factors may be built into the system, triggered by electrolyte
level. Thus, a high shutdown level may be included such that the
microprocessor
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will shut down the generator should the level sensing device 58 detect that
electrolyte has reached that level. Conversely, a low shutdown level may also
be
provided.
The level detector 134 in base 128 will indicate to the microprocessor and
hence to the vehicle operator that the liquid level in the reservoir is low,
signalling
that bottle 126 must be replaced.
The described temperature sensors will work through microprocessor 152
to control the various heaters as required. This will generally only be at
start-up in
particular climates
