Improved Methods and Apparatus for Utilizing Compressed Air for the Production of Cold.
Year: 1888

page_text: Date of Application, 28th Dec., 1888
Complete Specification Left, 18th Sept., 1889-Accepted, 30th Nov., 1889
PROVISIONAL SPECIFICATION.
Improved Methods and Apparatus for Utilizing Compressed Air for
the Production of Cold.
I, VICTOR POPP of 10 Rue St. Fargeau, Paris, France, Manager of La
Compagnie des Horloges Pneumatiques do hereby declare the nature of this inven-
tion to be as follows:
In compressed air installations in which use is made of the compressed air to
produce cold, this result is sometimes effected by simply opening a cock to allow the
air to escape into the space which it is desired to maintain at a low temperature; this
is a very simple but very costly method by reason of the loss of work resulting from
this escape of compressed air.
Another method consists in utilizing the exhaust from the cylinder of a compressed
air motor. This method is economical, but is not always feasible since it necessitates
the installation of a motor as well as of refrigerating apparatus.
The present invention has for its object the attainment of the same economical
result without necessitating this special installation of apparatus for doing.extraneous
work, and relates more particularly to such cases in which it is desired to produce
cold economically by the expansion of compressed air supplied by a conduit from any
suitable source.
According to this invention when there is no immediate employment handy or
convenient for this motive power, it is first utilized to operate air compressors.
Compressed air, supplied by compressors operated by this means can be discharged
and a part of it be afterwards returned into the main supply conduit.
The air exhausting from these compressors, after having done work, is employed
to produce the desired refrigeration. This refrigeration will thus not cause any loss
of useful work beyond that due to the inefficiency of the mechanism and will be pro-
duced at a cost almost nil.
This operation is effected by means of an improved machine which restores in a
cold and dry state a portion of the compressed air which has served to operate the
piston in the cylinder.
In the annexed sheet of illustrative drawings
Fig. 1 is an elevation of the improved machine.
Fig. 2, a plan of the same, partly in section.
Fig. 3, a vertical cross section on the line 1-2; and
Fig. 4, a partial cross section on the line 3-4 of Fig. 2.
In this arrangement, the compressed air distributed by the slide d to the expansion
cylinder a gives up part of its motive force to the crank shaft carrying one or
more regulating fly wheels, and also serves to compress in a second cylinder b,
the cold air which is drawn in through the pipe m and past the valve from the
refrigerating chambers. The relative volumes of the two cylinders are such that
the work done in the compressing cylinder is nearly equal to that given off in
the motive power cylinder.
The exhaust of the air expanded in the cylinder a is effected by means of a
slide valve e, which is balanced by the pressure of the air upon a small piston f
upon the face of which it is brought by a small pipe g (Fig. 3) branching off
from the end of the cylinder a.
The cold air thus escaping past the slide valve e is conveyed to the refrigerating
apparatus by a pipe l.
The slide valves d and e, are operated by means of two small cylinders and i.
The distribution in these cylinders is effected by means of small and very light slide
valves actuated by cams j and k on the driving shaft.

page_text: The air of the refrigerating chambers drawn into and re-compressed in the
cylinder is forced past the valve o and through a pipe p back into the main
conduit or any suitable receiver.
In this arrangement the small cylinder c (Figs. 2 and 4) has for object to adjust
the power absorbed by the compressing cylinder to that given out by the motor
cylinder by increasing or diminishing the dead or waste space behind the piston of
the compressing cylinder.
According to this improved system, the compressed air is not only utilized in a
complete manner but a portion of it is taken again, compressed anew and restored to
the main conduit. The air thus fulfills a double purpose of motive fluid and
refrigerant.
The air thus restored to the cold and dry state, may be utilized in any suitable
apparatus, but preferably in a special arrangement of apparatus designed more par-
ticularly to work in combination with the machine hereinbefore described.
This refrigerating apparatus is illustrated in Fig. 5 in vertical cross section,
in Fig. 6 in longitudinal section and in Fig. 7 in plan.
In these figures A is a motor. It may be a compressed air motor of the usual kind,
or of the construction just described. The refrigerating apparatus comprises a
chamber B with double walls, with a suitable space between these walls. The cold
compressed air circulates in this chamber as indicated by the arrows in Fig. 6, in such
a manner as to completely surround the refrigerating compartments or chambers ( in
which are contained the substances to be preserved.
The compressed air is conveyed from the exhaust of the motor to the chambers B
by a pipe D it passes out of these chambers by a conduit after having circulated as
described above.
The circulation of cold air around the chambers C may be prolonged by providing
a greater number of baffles or partitions, and by forming the walls of these chambers
with undulating surfaces so as to increase the surface in contact with the cold air.
The air contained in the chambers C is only renewed when desired; this renewal
is effected through the orifices F. which may be closed by means of plugs or
registers.
In the arrangement hereinbefore described, the air passes directly from the exhaust
of the motor into the refrigerating chambers. It is to be understood that this motor
may be of any usual kind or it may be the air compressing motor hereinabove
described.
Dated this 28th day of Dovambor 1888
VICTOR POPP,
Per L. W.
COMPLETE SPECIFICATION.
Improved Methods and Apparatus for Utilizing Compressed Air for
the Production of Cold.
1, VICTOR POPP, of 10 Rue St. Fargeau, Paris, France, Manager of La Compagnie
des Horloges Pneumatiques, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement
In compressed air installations in which use is made of the compressed air to
produce cold this result is sometimes effected by simply opening a cock to allow the
air to escape into the space which it is desired to maintain at a low temperature; this
is a very simple but very costly method by reason of the loss of work resulting from
this escape of compressed air.
Another method consists in utilizing the exhaust from the cylinder of a compressed
air motor. This method is economical, but is not always feasible since it necessitates
the installation of a motor as well as of refrigerating apparatus.
L
The present invention has for its object the attainment of the same economical
result without necessitating this special installation of apparatus for doing extraneous 5

page_text: work and relates more particularly to cases in which it is desired to produce cold
economically by the expansion of compressed air supplied by a conduit from any
suitable source.
According to this invention when there is no immediate employment handy or
convenient for this motive power, it is first utilized to operate air compressors.
Compressed air, supplied by compressors operated by this means can be discharged
and a part of it be afterwards returned into the main supply conduit.
The air exhausting from these compressors, after having done work, is employed to
produco the desired refrigeration. This refrigeration will thus not cause any loss of
useful work beyond that due to the inefficiency of the mechanism and will be produced.
at a cost almost nil.
This operation is effected by means of an improved machine which restores in a cold
and dry state a portion of the compressed air which has served to operate the piston
in the cylinder.
In the sheet of illustrative drawings filed with my Provisional Specification
Fig. 1 is an elevation of the improved machine.
Fig. 2 a plan of the same, partly in section.
Fig. 3 a vertical cross section on the line 1-2; and
Fig. 4 a partial cross section on the line 3-4 of Fig. 2.
In this arrangement, the compressed air distributed by the slide d to the expansion
cylinder a gives up part of its motive force to the crank shaft carrying one or
more regulating fly wheels, and also serves to compress in a second cylinder 4, the
cold air which is drawn in through the pipe m and past the valve n from the refrige-
rating chambers. The relative volumes of the two cylinders are such that the work
done in the compressing cylinder is nearly equal to that given off in the motive
power cylinder.
The exhaust of the air expanded in the cylinder a is effected by means of a slide
valve e which is balanced by the pressure of the air upon a small piston ƒ upon the
face of which it is brought by a small pipe g (Fig. 3) branching off from the end of
the cylinder a.
The cold air thus escaping past the slide valve e is conveyed to the refrigerating
apparatus by a pipe L. The slide valves and e are operated by means of two small
cylinders hand. The distribution in these cylinders is effected by means of small
and very light slide valves actuated by cams and on the driving shaft.
The air of the refrigerating chambers drawn into and recompressed in the cylinder &
is forced past the valve o and through a pipe p back into the main conduit or any
suitable receiver.
In this arrangement. the small cylinder (Figs. 2 and 4) has for object to adjust
the power absorbed by the compressing cylinder to that given out by the motive
cylinder by increasing or diminishing the dead or waste space behind the piston of the
compressing cylinder.
As above stated the end of the cylinder in which the small piston f is arranged,
communicates with the end of the cylinder a, so that the piston does not act at the
moment the slide e is about to move.
According to this improved system, the compressed air is not only utilized in a
complete manner but a portion of it is taken again, compressed anew and restored to
the main conduit. The air thus fulfils a double purpose of motive fluid and
refrigerant.
The air restored as above described to the cold and dry state, may be utilized in
any suitable apparatus, but preferably in a special arrangement of apparatus
designed more particularly to work in cou.bination with the machine hereinbefore
described.
This refrigerating apparatus is illustrated in Fig. 5 in vertical cross section,
in Fig. 6 in longitudinal section and in Fig. 7 in plan.
A is a motor. It may be a compressed air motor of the usual kind, or of the con-
struction just described. The refrigerating apparatus comprises a chamber B with
double walls, with a suitable space between these walls. The cold compressed air

page_text: circulation in this chamber as indicated by the arrows in Fig. 6 in such a manner as
to completely surround the refrigerating compartments or chambers in which the
substances to be preserved are contained.
The compressed air is conveyed from the exhaust of the motor to the chambers B
by a pipe D; it passes out of these chambers by a conduit E after having circulated
as described above.
The circulation of cold air around the chambers may be prolonged by providing
a greater number of baffles or partitions, and by forming the walls of these
chambers with undulating surfaces so as to increase the surface in contact with the
cold air.
The air contained in the chambers is only renewed when desired; this renewal
is effected through the orifices F which may be closed by means of plugs or
registers.
In the arrangement hereinbefore described, the air passes directly from the exhaust
of the motor into the refrigerating chambers. It is to he understood that this motor
may be of any usual kind or it may be the air compressing motor hereinabove
described.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. A machine or apparatus for utilizing compressed air for the production of cold
comprizing a motor and a refrigerating appliance, the arrangement being such that
compressed air passes into the motor cylinder in which it gives up motive power, then
passes to the refrigerating appliance from which it is afterwards drawn and com-
pressed by the motor and returned to the main conduit, substantially as described and
for the purpose specified.
2. In a compressed air motor the exhaust from which is utilised for the purpose of
producing refrigeration, the arrangement of the slide e with balancing piston f
communicating with the expansion cylinder as described and for the purpose
specified.
3. In a compressed air motor having an expansion cylinder and a compression
cylinder the employment of an equilibrium cylinder e that allows the volume of the
dead space of the compression cylinder to be regulated, as described with reference to
the annexed illustrative drawing.
4. In a machine supplying cold and dry air designed for refrigerating appliances,
the combination of an expansion cylinder a with slides for distribution and exhaust,
which are operated by pistons in small cylinders h and i; a compression cylinder b
for drawing in the cold air and returning it into the conduit and a cylinder
allowing of the balancing of the machine by regulating the dead space in the
compression cylinder as hereinbefore described with reference to the illustrative
drawings annexed.
5. The combination of refrigerating chambers for cold and dry air such as
described with reference to Figs. 5 to 7 of the drawings with a motor such that
the air to serve for refrigeration performs work in the motor before passing into the
refrigerator.
Dated this 18th day of Sentember 1080
V. POPP,
Per L. W.