robar

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**Sheldon ROBAR**

**Freon Engine**

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**<http://www.novanewsnow.com/article-245337-Nova-Scotias-engine.html>**

**Nova Scotias Engine Inventor Sticks
to Guns**

**by** **Mark Roberts/The Advance**

September 2nd 2008

The Queens Co. inventor of an emissions free engine  depending
on the fuel source - has been negotiating with an
out-of-province investment group to keep his technology in
Nova  Scotia.

Sheldon Robar says, We finally passed one of the many hurdles
of the negotiations. Nova Scotia comes first. This is where I
want to start and after five weeks, they reluctantly agreed. The
good part is one guy in that group understands the
thermodynamics of refrigerants. He understands it (technology)
will work, which you cant read out of a book because this book
hasnt been written yet.

One reason Robar says he is remaining loyal to the province is
he is happy at this point with the response of the
Progressive-Conservative government.

Were waiting for a meeting with the Energy Minister (Richard
Hurlburt), which we feel confident will occur through (Human
Resources Minister) Carolyn Bolivar Getsons office. He adds
Bolivar-Getson has been helpful as well.

Robar has spent over 27 years developing an engine that relies
on a heated refrigerant propellant thats ozone friendly. The
closed loop system releases no emissions and requires extremely
low heat temperatures for vapourization to occur and expand to
generate the force needed to move a vehicle, generator and many
other forms of machinery. Utilizing waste heat, as one example,
is a potentially huge market, Robar says.

He says he spurned other offers because of the thermodynamics
expert mentioned above. Because of business negotiations, The
Advance-confirmed investment group must remain anonymous, as
usually occurs.

Robar adds it hasnt hurt that a former version of the
technology has been patented at the United States Patent Office.

The expert actually received a physical copy of a spring The
Queens County Advance in which an article appeared about the
invention, understood the potential and contacted Robar.

Representing the group, he, and possibly others, is visiting
Nova Scotia early this month to work on the business details.

Robar says, The article sparked his interest. He said he
always knew it could be done; he just didnt know how to do
it.

Since the article, Robar has also talked to at least two
government-funded agencies.

Theyve only been an hindrance, which didnt discourage me at
all. It took 27 years to build this; Im not about to quit in 27
months.

Now, however, he says, Weve got a formidable task ahead of
us. There are a lot of regulations and guidelines in place and
we want to abide by them.

He is hoping a board of directors will be formed by the end of
the month.

After three decades, people would expect the inventor to be
excited by this news but he appears to be calm about his dream.

When we pound this through and see it on the market, then Ill
be excited. The biggest thing is I stuck to my guns. Its my
feeling Nova Scotia needs this more than any other province
because so much is coal fired.

He adds he is proud to be taking action --- instead of just
talking about it --- that is expected to help both the
environment and economy at the same time.

Information about timelines, jobs and other business details
will be released in the future, he says.

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**USP # 5,182,913**

**Engine System Using Refrigerant Fluid**

1993-02-02   
Inventor: ROBAR SHELDON C (CA); FRASER DAVID W (CA); WILEY
BERNARD A (CA)   
 Classification:  - international: F01K25/08;
F02B75/02; F01K25/00; F02B75/02; (IPC1-7): F01K25/10;  -
European: F01K25/08   
Also published as: CA2033462 (C)

**Abstract ---** An engine system using refrigerant fluid is
capable of utilizing the heat produced by an external
high-efficiency hydrocarbon fuel combustion process. The heat
from that process is utilized to transform the refrigerant fluid
from a liquid state to a gaseous state in a cycle which includes
extracting work from the fluid in the gaseous state in a
high-compression-ratio piston engine. The cycle further includes
transforming the fluid in the gaseous state back to the liquid
state in a condenser, and then feeding that fluid under pressure
to a heating chamber where the combustion process heat again
returns it to the gaseous state at high pressure and
temperature. The engine system has a higher efficiency than
hydrocarbon fuel combustion engines, and has particular
application to use in automobiles. One preferred refrigerant
fluid for this engine system is
2,2,Dichloro-1,1,1,Trifluoro-Ethane.

Current U.S. Class:  60/671 ; 60/660   
Current International Class:  F01K 25/00 (20060101); F01K
25/08 (20060101); F02B 75/02 (20060101); F01K 025/10 ()   
Field of Search:  60/651,671,660   
References Cited [Referenced By]   
U.S. Patent Documents:  3531933 October 1970 Baldwin
//  4109468 August 1978 Heath // 4738111 April 1988 Edwards

**Description**

The present invention relates to an engine system, and more
particularly, to an engine system that utilizes a refrigerant
fluid as a working fluid.

Two drawbacks of conventional internal combustion engines are
their inefficiency in utilizing increasingly-scarce hydrocarbon
fuels and their creation of airborne pollutents. These factors
are related in that an internal combustion engine, no matter how
finely tuned, cannot fully utilize the combustion process.
Rather, such an engine expels undesirable high-temperature
combustion products, such as nitrogen oxides (NO.sub.x), carbon
monoxide (CO), and unburned hydrocarbons (HC). If an engine
system could be developed that more fully utilized hydrocarbon
fuels, such a system would have the twin advantages of taking
more energy from the fuels while creating more acceptable
byproducts.

The engine system of the invention produces these advantages by
utilizing a refrigerant fluid, i.e. a fluid of the type normally
utilized with refrigeration equipment, as a working fluid. A
hydrocarbon fuel or other heat source, utilized in a
high-efficiency combustion process, provides heat to a heating
chamber into which the working fluid is directed. The working
fluid is there transformed from a liquid phase to a gaseous
phase. The gaseous working fluid is then directed to a
two-stroke engine having a high-compression ratio; in some cases
it may be possible to utilize a conventional diesel engine. As a
portion of the pistons of the engine are driven downward by the
pressure of working fluid that has entered through synchronized
inlet valve means, the other pistons expel working fluid through
synchronized outlet valve means. The working fluid, then at a
reduced pressure, is directed to a condenser where it is
returned to the liquid state by removal of heat. From the
condenser the working fluid is ready to be pumped once again to
the heating chamber. The efficiency of this engine system is
estimated to be at least twice that of conventional
hydrocarbon-fuel internal combustion engine systems.

In one form, the invention is an engine system that is adapted
to employ a refrigerant fluid as a working fluid and comprises a
condenser, a pump, a heating chamber, a heat source, and a
two-stroke high-compression-ratio piston engine. The condenser
removes heat from the working fluid such that the fluid is
transformed from a gaseous state to a liquid state. The working
fluid in the liquid state is pumped by the pump from the
condenser to the heating chamber. The heat source supplies heat
to the heating chamber such that the working fluid is
transformed from the liquid state to the gaseous state.

The working fluid in the gaseous state drives a
high-compression-ratio piston engine having reciprocating
pistons connected to a rotatable crankshaft. The crankshaft has
a series of journals each connected by a respective connecting
rod to a respective one of the pistons. Each piston is housed in
a cylinder having a working fluid inlet valve means and a
working fluid outlet valve means, the total of the inlet valve
means controlling flow of the working fluid to the engine from
the heating chamber, and the total of the outlet valve means
controlling the flow of the working fluid to the condenser from
the engine. The rotation of the crankshaft determines the
opening and closing of each of the inlet and outlet valve means.
Each inlet valve means is open between approximately one-quarter
and approximately one-half of the downward motion of the
associated piston, and each outlet valve is open for
substantially all of the upward motion of the associated piston.

The engine may be a two-stroke engine with an even number of
cylinders. The crankshaft may have a series of journals arranged
in pairs such that one of each pair extends in a direction
angularly-opposed on the crankshaft from the other of that pair.
Each pair of journals may occupy a respective one of a series of
planes that together divide a circle normal to and centred on
the crankshaft into a set of equiangular segments.
Alternatively, all of the pairs of journals may occupy the same
plane through the axis of the crankshaft; in this arrangement,
as half of the pistons are moving through top-dead-center (TDC)
the other half of the pistons are moving through
bottom-dead-center (BDC).

It is also possible for the engine to be a two-stroke engine
having an odd number of cylinders, although such engines are
more difficult to build and balance than are engines with even
numbers of cylinders.

The engine system may have a compression ratio of between
approximately 12-to-1 and approximately 15-to-1. The pump may be
driven by the piston engine, and may also have a throttle
assembly for controlling the quantity of working fluid flowing
to the piston engine from the heating chamber. If the engine
system is installed into an automobile, the condenser may be a
fan-cooled radiator and the piston engine may have at least four
cylinders. The heating chamber may be one chamber of a heat
exchanger having two chambers each on an opposite side of a heat
conductive wall, combustion gases produced by the heat source
being passed through the other chamber. The heat source may
include a propane, gasoline or natural gas storage tank and an
associated burner element. The engine system may further
comprise a starter engine connectable to the crankshaft of the
piston engine and powered by an electrical power storage means.

The pressure of the working fluid between the pump and the
heating chamber and between the heating chamber and the piston
engine may have a value between approximately 300 p.s.i.g.
(pounds per square inch gauge) and approximately 800 p.s.i.g.
The pressure of the working fluid between the piston engine and
the condenser may have a value between approximately 0 p.s.i.g.
and 50 p.s.i.g.

The engine system may further comprise a centrifugal
advancement mechanism for advancing the opening and closing of
each of the inlet and outlet valve means relative to the
rotation of the crankshaft. The mechanism comprises a shaft
connected to rotate with the crankshaft, a concentric cylinder
mounted to surround the shaft, and a pair of arms mounted on the
cylinder such that each arm extends diametrically opposite the
other on the cylinder. The concentric cylinder is connected to a
camshaft that determines the opening and closing of the each of
the inlet and outlet valve means. Each arm is pivotally mounted
on the cylinder such that a larger end of each arm moves
outwardly on the cylinder against bias with increasing
rotational speed of the cylinder. A second smaller end of each
arm has a portion extending generally radially inwardly into the
shaft. An increase in the rotational speed of the shaft results
in a rotation of the arms which in turn results in the
concentric cylinder rotating slightly relative to the shaft to
advance the opening and closing of the inlet and outlet valve
means relative to the rotation of the crankshaft.

The invention will next be more fully described by means of a
preferred embodiment utilizing the accompanying drawings, in
which:

**FIG. 1** is a partially-sectioned view of the engine
system of the preferred embodiment.

![](fig1.jpg)

**FIG. 2A** is a partially-sectioned view of the two-stroke
engine of the preferred embodiment, the view being taken through
one cylinder on the downward motion of the cylinder piston.

![](fig2.jpg)

**FIG. 2B** is a partially-sectioned view of the two-stroke
engine of FIG. 2A, but illustrating the cylinder piston in its
upward motion.

**FIG. 3** is a sectioned view of a throttle assembly for
the engine system of the preferred embodiment.

![](fig3.jpg)

**FIG. 4A** is a schematic view of a first type of
crankshaft used in the engine of FIG. 1, the view illustrating
six journals on the crankshaft sitting in the same plane through
the axis of the crankshaft.

![](fig4.jpg)

**FIG. 4B** is a schematic view of a second type of
crankshaft used in the engine of FIG. 1, the view illustrating
six journals on the crankshaft sitting in three planes
equiangularly positioned around the axis of the crankshaft.

**FIG. 5** is a plan view of a centrifugal mechanism for
advancing the opening of the inlet valve means of the engine
with increases in the rotational speed of the crankshaft.

![](fig5.jpg)

**FIG. 6** is a perspective view of an experimental
apparatus utilized for testing of the engine system of the
preferred embodiment.

![](fig6.jpg)

With initial reference to FIG. 1, a liquid rerefrigerant fluid
11 sits in the bottom of a condenser 12. The liquid refrigerant
fluid utilized in this embodiment is the commercially-available
product known as "FREON 114", although other refrigerant fluids
with better thermodynamic characteristics are presently under
development for use in this process. An emergency relief valve
13 is fixed to condenser 12; it will only open if the pressure
in condenser 12 should exceed a very high limit such as 1000
pounds per square inch (p.s.i.g.) due to a fire or similar
cause. Condenser 12 may be air-cooled or liquid-cooled and could
take the form, for instance, of the air-cooled radiator that is
found in most automobiles. A pump 14 draws fluid 11 from
condenser 12 and increases the pressure on that fluid to
approximately 600 p.s.i.g. in a conduit 15, that . pressure
being controlled by pressure relief valve 16, which opens to
allow excess fluid 11 in conduit 15 to return to condenser 12.
For an effective engine system, the pressure downstream of pump
14 could be set as low as approximately 300 p.s.i.g. or as high
as approximately 800 p.s.i.g. The value chosen depends on the
strength of the materials employed in constructing the engine
system and on the performance required from the system.

The flow of fluid 11 out of conduit 15 is also controlled by a
pressure control valve 17 which meters the amount of fluid 11
passing through an injector 18 into an annular combustion
chamber 20. Heat is transferred to chamber 20 from the
combustion of propane fuel stored in tank 21 by means of a
burner element 22; it is possible to alternately use other
fuels, such as natural gas, gasoline, oil or other hydrocarbon
fuels. The heat is applied to combustion chamber 20 until the
temperature of the fluid 11 in chamber 20 is approximately 300
degrees Fahrenheit. As with the pressure values selected, this
temperature value is selected for purposes of the preferred
embodiment; a greater or lesser value could be selected. A heat
sensor 24 senses the temperature in chamber 20 and provides a
controlling feedback signal to burner element 22. Burner element
22 is anticipated to be a complete-combustion
very-high-efficiency unit of the type commonly now being
installed in home heating furnaces.

When pressure control valve 17 is opened, liquid refrigerant
fluid 11 is injected through injector 18 into combustion chamber
20 at the 600 p.s.i.g. pressure in conduit 15. As fluid 11 comes
into contact with the heated chamber 20, it is transformed from
the liquid phase into the gaseous phase. A pressure sensor 26
senses the pressure in chamber 20 and provides a controlling
feedback signal to pressure control valve 17 to limit the
pressure in chamber 20 to approximately 500 p.s.i.g. A pressure
as high as 800 p.s.i.g. might be selected if appropriately
strong materials were utilized for chamber 20.

To start a two-stroke high-compression-ratio engine generally
designated as 30 in FIG. 1, a pressure control valve 31 is
slowly opened. Control valve 31 could be a throttle assembly as
shown in FIG. 3, the operation of which will be subsequently
described. Engine 30 of the preferred embodiment has an even
number of cylinders 31, each having a piston 33 with rings 34
connected by means of a connecting rod 35 to a crankshaft 36. An
engine with an odd number of cylinders could also be
implemented; however, such an engine would be more complex
because of the careful balancing required. In the preferred
embodiment of the engine 30, the journals are arranged in pairs,
one member of each pair extending in a direction
angularly-opposed on crankshaft 36 from the other member of the
pair. Each pair of journals occupy a respective one of a series
of planes that divide a circle normal to and centred on the
crankshaft into a set of equiangular segments. For instance, in
a four-cylinder engine the journals extend at 90-degree
intervals, whereas in a six-cylinder engine the journals extend
at 60-degree intervals, etc. A crankshaft associated with a
six-cylinder engine using this arrangement is shown in FIG. 4A.
It is also possible, although less preferred, to place all of
the journals of crankshaft 36 into a single plane, such that
half of the journals of crankshaft 36 are positioned
angularly-opposite the other half of the journals relative to
the axis of rotation of crankshaft 36. A crankshaft associated
with a six-cylinder engine having this arrangement is shown in
FIG. 4B. With this arrangement, when half of the pistons 33 in
engine 30 are at top dead center, the other half of the pistons
33 are at bottom dead center. For purposes of more even power
distribution, an engine having the staggered journal position
illustrated by FIG. 4A is preferred.

Associated with each cylinder 31 is an inlet valve 38 and an
outlet valve 39, as shown in FIGS. 1, 2A and 2B. The opening and
closing of the valves 38 and 39 is controlled by a cam member
(not shown) that is connected to crankshaft 36 through a
centrifugal advancement mechanism which is illustrated in FIG. 5
and described more fully subsequently. The opening and closing
of engine inlet and outlet valves by means of cam member
rotation is assumed to be known to those skilled in the art of
engine construction and is not further described.

As the gaseous refrigerant fluid 11 (at 500 p.s.i. g. in this
embodiment) enters those cylinders 31 that have their inlet
valves 38 open, fluid 11 creates a downward pressure on the
pistons 33 in those cylinders. Each inlet valve 38 is connected
to a cam member on the crankshaft such that it remains in the
open state during the time that the respective piston 33 moves
from a few degrees past top dead center (TDC) to a value between
approximately one-quarter and approximately one-half of the
downward motion of the associated piston. Experimentation has
found that acceptable engine performance is obtained over a
range extending from approximately 30 degrees past TDC to
approximately 120. degrees past TDC. As each piston 33 moves
past BDC the outlet valve 39 on its respective cylinder 31 opens
(due to cam member position at that time). Because the engine
utilized in this system is a high-compression-ratio engine
having a compression ratio of at least 12-to-1, the pressure of
refrigerant fluid 11 at the point at which outlet valve 39 opens
has been reduced to a value between approximately 0 p.s.i.g. and
50 p.s.i.g. due to the downward motion of the piston 33. The
actual value of the pressure of fluid 11 in cylinders 31 at BDC
depends upon the ambient temperature of the air surrounding the
engine system and the type of refrigerant gas used. For each
piston 33 that is commencing its upward motion in its respective
cylinder, another piston 33 is commencing its downward motion in
its respective cylinder (the two pistons being angularly-opposed
on crankshaft 36). The cam member is shaped such that the outlet
valves 39 remain open for expulsion of the refrigerant fluid 11
during approximately the whole upward motion of each piston 33,
i.e. from the time the piston 33 passes through BDC to almost
the time it passes through TDC. To avoid contact between a
piston 33 and an inlet valve 38 or an outlet valve 39 as the
piston passes through TDC, the valves are either recessed into
the head of the engine or the face of each piston is shaped to
accommodate the valves. FIGS. 2A and 2B illustrate the downward
and upward motion of the pistons 33, respectively, and the
relative position of inlet valves 38 and outlet valves 39.

From the outlet valves 39, the `spent` refrigerant fluid 11
moves at a pressure of between 0 p.s.i.g. and 50 p.s i.g. and a
temperature of approximately 90 degrees Fahrenheit through an
exhaust conduit 40 to the condenser 12. In condenser 12 heat is
removed from fluid 11 through air-cooling or other means, and
fluid 11 is transformed from the gaseous state into the liquid
state. Fluid 11 then repeats its working cycle. Conduit 41
provides flow communication between the inside of crankcase 42
of engine 30 and the inside of condenser 12 for preventing a
build-up of pressure within crankcase 42. Engine 30 has an oil
pump (not shown) for pumping oil 43 from the base of crankcase
42 through channels terminating in the walls of the cylinders
31. A pressure relief valve 44 ensures that if the pressure in
combustion chamber 20 exceeds 500 p.s.i.g. by more than a
defined margin, valve 44 opens and the excess refrigerant gas is
passed through conduit 45 directly to condenser 12. Between
conduit 46 carrying fluid 11 into engine 30 and conduit 40
carrying fluid 11 away from engine 30 is a vacuum break 47,
which is a small valved conduit which opens to allow fluid 11 to
flow from conduit 40 to conduit 46 whenever the conduit 46
experiences a negative pressure above a predetermined value.
Vacuum break 47 is necessary for the smooth operation of engine
30 during those times when throttle 31 is closed.

The preferred embodiment of the two-stroke engine has an even
number of cylinders, i.e. 2, 4, 6, 8, etc., with parallel flow
communication between the pressure control valve 31 and all of
the inlet valves 38. Similar parallel flow communication exists
between all of the outlet valves 39 and the condenser 12. The
amount of working fluid power available to the engine is
maintained at a generally constant level by means of feedback
through heat sensor 24 and pressure sensor 26. Heat sensor 24
signals burner element 22 to increase the amount of heat
provided if the temperature in combustion chamber 20 drops below
approximately 300 degrees Fahrenheit. Similarly, pressure sensor
26 signals pressure control valve 17 to increase the flow rate
of working fluid to injector 18 if the pressure in combustion
chamber 20 drops below approximately 500 p.s. i.g. Control valve
31 is used to vary the amount of available working fluid power
that is actually transmitted to engine 30.

One construction of control valve 31 suitable for use with an
engine system installed in an automobile is shown in FIG. 3. The
depression of a foot pedal 50 rotates a lever arm 51 clockwise,
raising a tapered plunger 52 from an annular seat 53 to allow a
controlled amount of fluid 11 to flow to engine 30. An idle
by-pass line 55, with an associated idle control valve 56, may
be built into the system to allow a small amount of fluid 11
sufficient for idling to flow to engine 30 even at times when
valve 31 is closed.

FIG. 5 illustrates a centrifugal advancement mechanism that may
be used to advance the opening and closing of the inlet valves
38 and outlet valves 39 as the rotational speed of crankshaft 36
increases. Shaft 60 is connected to crankshaft 36 through a belt
or chain to rotate directly with crankshaft 36. Disc 61 is
mounted on shaft 60 such that it can rotate slightly relative to
shaft 60. Mounted to disc 61 to rotate with that disc is a cam
member (not shown) on which a cam follower rides for opening and
closing the inlet valves 38 and outlet valves 39. A pair of arms
62 are each rotatable on a respective heavy pivot pin 63. Each
arm 62 has an ear 64 extending into a complementary groove in
the side of shaft 60. A spring 65 is connected between the one
end of each arm 62 and a pin on the rotational axis of shaft 60.
A pair of stops 66 limit the outward movement of the arms 62.
Slight relative rotational movement between shaft 60 and disc 61
occurs as shaft 60 increases its rotational speed. By this
arrangement, the inlet valves 38 open a few degrees before TDC
at high rotational speed of crankshaft 36; this allows the
working fluid 11 to enter the cylinders at an earlier point than
would be possible without this mechanism. When the engine 30 is
just starting to rotate, the springs 65 hold the arms 62 at
their most inward position which results in the inlet valves
opening at TDC or just past TDC.

In an automobile incorporating this engine system, the
condenser 12 is replaced by an air-cooled radiator similar to
the radiator in existing automobiles but larger. Also, an
electric starter engine may need to be utilized for starting
engines in which the crankshaft has its journals all in one
plane (as exemplified by the crankshaft of FIG. 4B). For engines
in which the crankshaft has journals angularly distributed about
its axis (as exemplified by the crankshaft of FIG. 4A), such a
starter engine is not required. An electric pump (powered by a
battery in the automobile) is required for initial
pressurization of the refrigerant fluid 11 in conduit 15. After
starting of the engine, the pressurization of that fluid may be
transferred to a mechanical pump driven by the engine.

FIG. 6 illustrates an experimental apparatus which was built to
test the feasibility of the engine system described. Engine 70
is a four-cylinder Volkswagen diesel engine with a
compression-ratio of approximately 15:1. This type of engine has
a crankshaft with four journals all extending in the same plane
in a similar manner to the arrangement of FIG. 4B. The diesel
fuel injectors and glow plugs of engine 70 were left in position
but were left unconnected for the experiments. A pulley 71,
secured to the end of a crankshaft 72, drives a pair of belts 73
and 74. The belt 73 extends around a pulley 77 which, through a
linkage inside of casing 78, controls the opening and closing of
the inlet and outlet cylinder valves of engine 70. The belt 73
also extends around a pulley 79 driving an oil pump (not shown),
and around an idler pulley 80 mounted for free rotation on block
82 of engine 70. The belt 74 extends around a pulley 83
connected to a pump 84 which pumps refrigerant fluid in the
liquid state from a radiator means generally designated 85 to a
heater means generally designated 86. Pump 84 is secured to the
block 82 by a bracket 87.

With further reference to the experimental apparatus
illustrated in FIG. 6, the radiator means 85 is comprised of two
radiator elements 89 and 90 secured together at an angle so as
to create a wedge-shaped central cavity. Each of the radiator
elements 89 and 90 comprises in part a continuous metal tube,
each tube having a series of segments extending in parallel
within the respective radiator element. Each of the
semi-circular segments 91 that extend from the end of the
radiator elements 89 and 90 connect a respective pair of the
parallel segments of the continuous tube extending through the
respective radiator element. A fan (not shown) is used to blow
air across radiator means 85.

The refrigerant fluid 11 in the liquid phase was pumped from
radiator means 85 along conduit 93 by pump 84. Pump 84 raised
the pressure of fluid 11 from approximately 20 p.s.i.g. in
radiator means 85 to approximately 600 p.s. i.g. in a downstream
conduit 94. The conduit 94 extended into the heater means 86,
which in the experiment consisted of a modified propane storage
tank 95 within which was fitted an electrical heating element
(not shown) connected to an electrical powercord 96. The
refrigerant fluid 11 was transformed from the liquid phase to a
gas having a pressure of approximately 500 p.s.i.g. by means of
the heat supplied by the heating element within tank 95. The gas
pressure was monitored by a pressure gauge 97 fitted to an
output conduit 98 of tank 95. A control valve 99 was fitted into
conduit 98 to control flow of the refrigerant fluid 11 to the
input manifold 100 of engine 70. The input manifold 100 provided
a reservoir for the refrigerant gas being introduced into the
four cylinders of the engine through the inlet valves on those
cylinders. The refrigerant gas leaving the cylinders through the
outlet valves entered the output manifold 101 at approximately
20 p.s.i. g., and was then carried by a conduit 103 back to the
radiator means 85. A pressure gauge 104 monitored the pressure
in conduit 103.

The refrigerant fluid that was utilized for the experiments was
dichlorotetrafluoroethane, which is known commercially to
refrigeration engineers under the trademark "FREON 114".
However, new `environmentally-friendly` refrigerant fluids will
shortly be commercially available that will have both higher
operating pressures and lower condensation pressures. Although
the engine system of the invention is a closed system in which
there is no more leakage to the environment than results from
use of the ordinary household refrigerator, the new
refrigeration fluids presently under development do not use
fluorohydrocarbons. One such `ozone-friendly` gas which is close
to commercial production is 2,2,Dichloro-1,1,1,TrifluoroEthane,
which is being developed by Dupont Chemical Company and will
carry the trade-mark "HCFC 123".

The engine system of this invention has been found to operate
at least twice as efficiently in terms of output energy to input
energy as conventional hydrocarbon-fuel internal combustion
engine systems in use in automobiles.

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