Improvements in Cold Air Refrigerating Machines.
Year: 1892

page_text: Date of Application, 22nd Jan., 1892
Complete Specification Left, 24th Oct., 1892-Accepted, 17th Dec., 1892
PROVISIONAL SPECIFICATION.
Improvements in Cold Air Refrigerating Machines.
I, WILLIAM GARDEN of 155 Amhurst Road Hackney in the County of
Middlesex, Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in cold air refrigerating machines in which
the air is first compressed and then cooled and expanded to produce the intense
cold required. In one form of machine constructed according to my invention a
compression and expansion cylinder are arranged at either end of a bed plate
the pistons being operated from a common crank or they may be placed tandem
wise as found most suitable.
With a single acting machine air is drawn into the compressor through an inlet
valve which consists of a frustum of a rubber cone suitably held, inside which is
placed a similarly shaped perforated plate, the suction causing the rubber cone to
be expanded or lifted so as to disclose the perforations. After compression the
dense air is expelled through a similar outlet-valve into a cooling chamber pre-
ferably arranged above the compressor in which water is maintained up to the
level of the air discharge pipe. This cooling chamber contains a number of per-
forated air diffusing plates preferably carried by bolts and spaced apart by distant
pieces which may be sections of tubes. To prevent the air on its entrance meeting
a large body of water a closed cushioning tube is arranged in the cooling chamber
the air in which causes a small body of water only to be kept over the inlet to
the cooler. In place of the arrangement of perforated plates in the body of water
as above described 1 may employ a chamber containing a number of perforated
plates, on which are laid other perforated plates, the latter being loosely kept in
place by pins or bolts. The holes in the second plate are out of line or are
"blind with the holes of the lower. Suitable overflow tubes connect the fixed
plates with each other, these tubes being so arranged that a certain depth of water
is always maintained over the plates the lower end of each pipe dipping into the
water on the plate below.
The cooling water is supplied to the top plate and overflows to the one below
and so on.
The dense air from the compressor rises through the perforations in
the lowest fixed plate, lifts the loose plate above and escapes through the per-
forations of same and through the body of water above, to the next, the loose
plate dropping when the pressure falls to maintain the water on the fixed plate.
A spray
of water is supplied to the compressing cylinder during the periods of
compression and delivery in order to abstract some of the heat from the air and in
a single acting machine of small capacity this water is subsequently forced up to
supply the cooling-chamber.
The supply for the spray is obtained by means of a pump which may be cast
onto the back cover of the compression cylinder if desired. This pump has a
hollow plunger which may be attached to the back of the piston and be in con-
nection with recesses formed on the back of same. These recesses are covered
by a plate slightly smaller in diameter than the cylinder. A valve is placed
between the hollow plunger and the plate which valve may be a rubber ring
covering openings or perforations in the head of the plunger, so that said ring
will be opened in one direction with the pressure of the water and will allow it to
escape into the recesses at the back of the piston and be delivered between same
and the plate in a fine spray around the edges of the piston said spray also assisting
in sealing the piston against any leakage of compressed air.
In a double acting machine it is necessary to inject the spray of water on one

page_text: side of the piston during its forward stroke and on the other side during its return.
To effect this I employ a hollow fixed plunger having a suitable inlet valve which
is connected to a supply of water, in this case for the sake of economy the water
which has been previously used in the cooler.
This plunger passes into the piston rod which is hollow and which is in communi-
cation with a hollow space in the piston.
The plunger has an outlet valve on one side of its head which allows water
to pass through to the space in the pistou. The piston contains a loose packing
ring arranged to drag slightly when the piston is travelling so that a space is
left partly around the piston through which the water may be delivered at a
fine spray, the piston for this purpose being slightly smaller than is necessary
for a tight fit in the cylinder on a part of its circumference. Water is drawn
through the hollow plunger into the hollow piston rod by the forward motion
of the latter, with the result that the body of water in the piston is discharged
in a fine spray partly around same on the forward side. On the return stroke
one half of the water thus drawn into the piston rod is expelled through the
outlet valve into the space in the piston and around same in a spray, on the
other side, being that against which compression is now taking place. On the next
forward stroke of the piston the other half is similarly ejected as before described.
The waste water is disposed of through an outlet in the bed plate, which outlet is
controlled by a ball cock valve or other similar contrivance.
After passing through the cooling chamber the dense air passes to the expanding
cylinder, the inlet valve of which is preferably applied to the end cover which
contains a chamber for the dense air. The valve consists of a plate carrying a
stuffing box, a perforated wall through which the dense air may pass, and a seat
attached to said wall on which the valve is pressed by a spring. Between the seat
and the end wall of the cylinder a rubber or other non-conducting packing is
interposed to prevent the valve seat freezing by the dense air depositing thereon.
Said valve is operated by means of a crank lever, one end of which carries a
friction roller which comes in contact with a slope or projection on the face of the
fly wheel, or is operated by a cam or the like. The outlet is a slide or grating
valve which uncovers the necessary ports, the reciprocating motion being imparted
to it from an arm which is moved by a sloping projection on the fly wheel or the
like. The arm may terminate in a fork which holds the valve plate and may carry
a spring to keep the plate up to the face of the ports. In large size machines the
valves may be worked by gear from the crank shaft in much the same way as
"Corliss or other quick cut off gears.
For the purpose of equalizing the temperature of the expanding cylinder and for
further cooling the dense air which may be necessary in large sized machines, the
dense air before entering the cylinder may be caused to pass into a chamber or
passage in connection with a casing around the cylinder which is filled or partly
filled with brine, the air passing up through a series of perforated plates in its
passage through which to a pipe leading to the expansion cylinder it lifts the brine,
forces it through the perforated plates, and causes it to continuously circulate
around the cylinder.
Dated this 22nd day of January 1892.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Applicant's Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Cold Air Refrigerating Machines.
I, WILLIAM GARDEN, of 155 Amhurst Road, Hackney, in the County of
Middlesex, Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement:-
My invention relates to cold air refrigerating machines in which the air is first
compressed by the operation of a steam engine or other suitable motor, then cooled,
and then expanded to produce the intense cold required. The compression and
expansion cylinders may be arranged in any suitable relative position, such as tandem-
wise, or one at either end of a bed plate, and the pistons of the two cylinders may both
be operated by a crank shaft placed between the said cylinders. The cylinders
may be arranged to operate either as single acting or as double acting cylinders.
The motor cylinder or cylinders may also be arranged relatively to the other
cylinders in any suitable manner and be connected to the motor shaft in any con-
venient way.
I will describe my invention with reference to the accompanying drawings.
Figure 1 is a longitudinal section. Figure 2 a plan and Figure 3 an end elevation
of a single acting machine illustrating my improvements. The other figures
illustrate details and the application to double acting machines as hereinafter
described.
Referring to Figures 1, 2 and 3 A is the compression cylinder, B the cooler
and C the expansion cylinder. The pistons a and c of the two cylinders are in this
instance connected by one rod d and driven from the crank e on the crank shaft E
operated by any suitable motor.
The valve for the inlet of air to the compression cylinder (see also Figure 7).
consists of flexible material such as vulcanized rubber in the form of a frustum of
an elongated or flattened cone with a flange it being secured and supported by a
correspondingly shaped perforated piece f2, the rubber covering the perforation or
perforations in the said piece f' when the piston a makes its compressing stroke but
being expanded or lifted when the piston is making its reverse stroke so as to
uncover the perforation or perforations for the inlet of air to the cylinder which air
is to be compressed by the piston when it makes its compressing stroke. The
outlet valve Ġ for the passage of the compressed air may be made, like the inlet
valve, that is to say of the flexible piece g and supporting perforating piece ², but
is of course reversely placed. There may be one such inlet and outlet valve or
two or more may be used. In Figure 2 I have shewn one outlet valve whilst in
Figure 8 I have shewn two. The compressed air passes through the said valve G
into the cooling chamber B which is preferably arranged above the compressing
cylinder and water is maintained in the said cooling chamber up to the level of the
air discharge pipe H. The said cooling chamber contains a number of perforated
air diffusing plates b which can conveniently be carried by bolts 62 and be spaced
apart by distance pieces which can take the form of short tubes 6³ encircling the
said bolts. To prevent the air on its entrance into the cooling chamber from
meeting a large body of water, a cushioning tube 4, closed at top and open at
bottom, is arranged in the cooling chamber B so that the air in the said tube causes
only a small body of water to be maintained over the inlet to the cooler that is to
say over the valve G. In place of the aforesaid arrangement of perforated plates
in the body of water I may employ the arrangement shewn in Figures 4, 5 and 6
wherein there are a number of fixed perforated plates 6 on each of which is laid
another perforated plate 6 having its perforations non-coincident with those in the
plate 6. The plates are kept in place laterally by pins and bolts, or other
suitable means, but so that the compressed air admitted to the cooling chamber

page_text: at G can raise them from the plates to allow the air to pass through the per-
forations in the several plates. There are overflow pipes from one perforated
plate to the other so arranged that a certain depth of water is maintained over
each plate the said pipes standing above the plates to the proper distance to allow
of the required depth of water over cach plate and dipping into the water on the
. plate below, the cooling water being supplied above the top plate and overflowing
from it to the one below and so on. The compressed air from the compression
cylinder entering the cooler by the pipe G2 rises through the perforations on the
lowest fixed plate lifts the loose plate above and passes through the perfora-
tions in that and through the water on the plate and so on upward through the
series of plates the moveable plates 6 returning onto the fixed plates 6 so as to
retain the water on the plates when the pressure of air ceases. A spray of water
is supplied to the compressing cylinder A during the period of compression and
delivery in order to abstract some of the heat from the air and in some cases (for
example in the case of a single acting machine of small capacity as shewn in
Figures 1, 2 and 3) this water can be subsequently forced up to supply the cooling
chamber. The supply for the spray to the compressing cylinder can be effected by
means of a pump the barrel I of which can conveniently be cast or affixed on the
back cover of the said cylinder as shewn in Figures 1 and 2. Figure 9 shews the
piston and part of the pumping arrangement in detail.
The pumping arrangement is preferably constructed as follows:-The pump has
a hollow plunger i which is shewn as being attached to the back of the piston a of
the compressing cylinder it being in conumunication at one end with the barrel [
and at the other end with a space or recesses formed at the back of the said piston
the said space or recesses being covered by a plate J slightly smaller in diameter
than the cylinder and piston a valve being placed between the hollow plunger and
the said plate J which valve may conveniently be a rubber ring covering
perforations in the head of the plunger so that the said ring during the com-
pressing stroke will by the pressure of water be caused to open so that water will
escape through the said perforations 2 into the space or recesses at the back of the
piston and be delivered from between it, or them, and the plate J, in a fine spray
issuing from around the edge of the piston on the compression side thereof the
said water also assisting in sealing the piston against any leakage of compressed air
past it.
In a double acting machine the spray of course requires to be ejected from both
sides of the piston, from one side during one stroke and from the other side during
the other stroke. To effect this I employ the arrangement shewn in Figure 10 and
in detail of certain of the parts in Figures and 12 consisting of a hollow fixed
plunger having an inlet valve at 2 which is connected by the pipe k³ to a supply
of water which may for the sake of economy be that which has been used in the
cooler. The said fixed plunger consists of a hollow stem k with a head, and enters
the hollow piston rod a' so that there is a space between the said rod and the stem k
which space is in communication with another space in the piston from which
openings lead into grooves around the said piston. The said plunger has an
outlet valve consisting of the perforations and flexible ring (see the enlarged
details Figures 11 and 12) which allows water to pass from the hollow stem k of
the plunger through the space between it and the hollow piston rod to the space l
in the piston. The grooves in the piston cach contain a loose packing ring m
arranged to drag slightly in its groove when the piston is travelling so that a space
is left around the piston at the outward side of that packing ring at which com-
pression is taking place through which space the water is delivered in a fine spray
the piston for this purpose being slightly smaller in diameter at the parts outwards
of the grooves 3 than is necessary for a tight fit in the cylinder. By the forward
motion of the hollow piston water is drawn through the hollow plunger into the
said hollow piston and water is also discharged therefrom in a fine spray into the
cylinder on the side on which the piston is compressing the air. On the return
stroke water is expelled through the outlet orifices into the space in the piston

page_text: 'The
and around it in a spray on the other side namely that against which compression
is now taking place. On the next forward stroke of the piston water is drawn in
and ejected on the other side of the piston as before described and so on.
waste water from the outlet pipes or from the cooler can be disposed of through
an outlet in the bed plate controlled by a ball cock valve p Figure 5 or other
suitable contrivance.
Referring again to the single acting machine the compressed air after passing
through the cooling chamber passes by the pipe H and passage H' and space H'
around the expansion cylinder C and enters the said cylinder, the inlet valve N of
which is preferably applied to the end cover which contains a chamber Hlor the
said air. This valve is shewn in section in Figures 19 and 20 and consists of a
plate or cover n carrying a stuffing box »² and having a perforated wall or casing no
through which the compressed air passes, and a valve seat n' attached to the said
wall or casing n³ to which seat the said valve is pressed by a spring n contained
in the hollow stem of the valve, and the hollow projection in which it slides.
Between the seat n' and the end wall of the cylinder a rubber or other non-
conducting packing n is interposed to prevent the valve seat from freezing by
the deposition of moisture from the compressed air. The said valve can be operated
in any convenient way for example by means of a double armed crank P P
Figures 2 and 3 one arm P of which is connected to the stem n³ of the valve the
other arm P carrying a friction roller p (Figure 3) which is acted on by a cam p²
on a shaft på operated by gearing from the shaft E as shewn clearly in Figure 2.
The outlet from the expansion cylinder is fitted with a slide or grating valve Q
(shewn separately in Figures 21 and 22) which opens and closes at the required
periods the necessary ports, the reciprocating motion being imparted to it in any
convenient way for example as shewn in Figure 15 through the rod q by means of
an arm operated by a cam q³ from the shaft p³. The spring returns the valve.
The rod terminates in a fork Figure 22 which holds the valve plate and may
carry a spring to keep the plate up to the face of the ports. In large size
machines the working of the valves by gear from the crank shaft may be effected
in much the same way as Corliss or other quick cut off gears as will be readily
understood. For the purpose of equalizing the temperature of the expanding
cylinder aud for further cooling the compressed air which may be necessary in
large size machines the compressed air before entering the cylinder may be caused
to pass into a chamber or passage in connection with a casing around the cylinder
which is filled, or partly filled, with a cooling medium such as brine. This is
illustrated by Figures 13, 14, 15 and 16 where R is the said casing. The air
entering at passes up through a series of perforated plates in the vessel R³ to
a pipe leading. to the expansion cylinder and forces the brine through the said
perforated plates and causes it to continuously circulate around the cylinder as
shewn by the arrows in Figure 15.
Figure 17 is a side elevation and Figure 18 a plan of a double acting machine
arranged according to my invention. Figure 10 shews the compression cylinder in
section and Figures 7 and 8 represent in sectional elevation and plan the inlet and
discharge valves thereof, as well as those in the single acting machine hereinbefore
described. Figures 4 and 5 are sectional elevations at right angles to each other
and Figure 6 a sectional plan of the cooling chamber. Figures 13 and 14 are a
sectional elevation and a plan of the expansion cylinder and Figures 19 and 20
shew one of its inlet valves and Figures 21 and 22 one of its outlet valves which
will also serve to shew more clearly the construction of these valves in the single
acting machine as they are the same.
It will be seen that the double acting machine is constructed substantially in the
same way as is the single acting machine but with duplications of the valves and
passages at either end of the cylinders and the construction will be readily under-
stood without further description.
The motor by which the machines described are operated may be of any suitable
description and be connected therewith in any convenient way for instance the

page_text: single acting machine shewn in Figures 1 and 2 may be operated by a driving belt
passed over the fly wheel on the crank shaft E or over a pulley fixed to the said
shaft which may be extended beyond the fly wheel for the purpose and the power
may be derived from an overhead shaft driven by a steam engine or other motor.
In the double acting machine the motive power can be conveniently obtained
from a steam cylinder or cylinders forming a part of the machine after the usual
manner.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. The arrangement and combination of parts constituting a single acting cold
air refrigerating machine substantially as hereinbefore described and illustrated in
the accompanying drawings.
2. The arrangement and combination of parts constituting a double acting cold
air refrigerating machine substantially as hereinbefore described and illustrated in
the accompanying drawings.
3. In or for cold air refrigerating machines an inlet or au outlet valve consisting
of a perforated inclined projecting or conical piece and correspondingly shaped
flexible piece for closing and opening the perforations in the first named piece
arranged as hereinbefore described and shewn more particularly in Figures 7 and 8
of the accompanying drawings.
4. In or for cold air refrigerating machines a cooling chamber containing air
diffusing plates and a closed air cushioning tube above the air inlet thereto substan-
tially as and for the purpose hereinbefore described and shewn in Figure 1 of the
accompanying drawings.
5. In or for cold air refrigerating machines a cooling chamber containing air
diffusion plates with perforations non-coincident so that the air lifts one plate from
the other to pass through the perforations whilst a layer of water is maintained above
each plate substantially as hereinbefore described and illustrated by Figures 4, 5
and 6 of the accompanying drawings.
6. The combination with the piston of the compressing cylinder of a cold air
refrigerating machine of a water space and a hollow plunger or hollow plunger and
hollow piston rod for spraying water from around the piston at the side where it is
compressing substantially as hereinbefore described and shewn in Figure 1 and
Figures 9, 10, 11 and 12 of the accompanying drawings.
7. In cold air refrigerating machines the combination of a casing around the
expansion cylinder and a vessel through which the air passes so as to circulate a
cooling medium through the said casing substantially as hereinbefore described and
shewn in Figures 13, 14 and 15 of the accompanying drawings.
Dated this 24th day of October 1892.
J. H. JOHNSON & Co.,
Agents.