Improvements in or relating to Refrigeration Apparatus.
Year: 1896

page_text: Date of Application, 5th May, 1896-Accepted, 13th June, 1896
Improvements in or relating to Refrigeration Apparatus.
A communication from GEORGE FRANCIS KNOX and ELIEL LONG SHARPNECK,
both of 21 Quincy Street, Chicago, Illinois, United States of America.
I, ALFRED JULIUS BOULT of 111 Hatton Garden in the County of Middlesex,
Chartered Patent Agent, 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:-
This invention relates to improvement in ice or refrigerating apparatus in which
anhydrous ammonia, or a like fluid, is employed as the cooling agent; the object
being more especially to provide apparatus for use where only a comparatively
small cooling-chamber, such as a butcher's, grocer's or domestic store-room, is to
be refrigerated. While the object is more especially as stated, the invention is
not to be limited to a machine or apparatus of any size or for any particular or
limited use.
The invention consists, first, in the general construction of the apparatus whereby
it is rendered particularly compact, durable and desirable for its purpose, second,
in a novel system of high and low pressure traps for arresting oil and liquid
ammonia, the traps being so located with relation to each other that each will have
a controlling influence upon the other, whereby the temperature of one will be
prevented from rising higher than desired and the temperature of the other will be
kept from falling to a lower extent than desired; third, in novel and improved
automatic regulating mechanism for controlling the gas-pressure in the refrigerating
conduit; fourth, in thermostatic mechanism for governing the action of the machine
and thereby maintaining an approximately even temperature in the cooling-chamber;
and fifth, in various novel details of construction, all tending to render the apparatus
automatic in its action, smooth-running, simple, inexpensive and capable of operating
indefinitely with comparatively little attendance.
Referring to the accompanying drawing-
Figure 1 is a view in the nature of a diagram showing the improved apparatus
in working condition, certain parts being broken away and other parts being shown
in section to illustrate mechanisms and constructions which would otherwise be
hidden; Figure 2, a top, plan view of the refrigerating-machine; and Figure 3, an
enlarged broken section taken on line 3 of Figure 1 and showing the construction
of the induction and eduction valves of the compressor.
The refrigerating-machine consists of a shell formed in suitable sections and
containing a compartment or chamber A for a liquid refrigerant (preferably
anhydrous ammonia) reservoir or supplier A', a compartment or chamber B
containing a condensing-coil B'; and a compartment or shaft-chamber C. A
suitable power transmitter D, which may be an electric motor, drives a pulley D'
which, through an eccentric and pitman connection, rocks a shaft D2 which extends
through and is journaled at opposite ends in the walls of the chamber C. The
rock-shaft carries a working-beam t which, at opposite ends, connects pivotally
with the stems of compressor-pistons C¹, C3, working in tubular extensions or
cylinders C, C on the chamber C. The tubular extensions are provided with
caps C constructed alike and shown in detail. in Figure 3. At each cap Care
two chambers sr, respectively, each chamber s containing an induction valve s¹,
which opens downward, and each chamber r containing an eduction-valve r which
opens upward. The chambers of the tubular extension C3, C4, are connected

page_text: together by what may be termed an induction-pipe or conduit ; and the chamber r
of the respective tubular extensions C3, C4, are connected together by what may be
termed an eduction conduit or pipe In the working of the compressor, as
hereinafter described, each piston, in its downward stroke, draws gas into the
respective cylinder from the induction pipe through the respective induction
chambers and valve st, and in its upstroke forces the gas from the respective
cylinder through the respective valve and eduction chamber r, into the eduction-
pipe
E is a shell or casing containing chambers E¹ and E. The chamber E' is
termed a low-pressure trap and the chamber E, a high-pressure trap. Extending
from the liquid-refrigerant supplier A' is a supply-pipe q. The pipe q communicates
with a pipe gl which in turn extends to a refrigerating-conduit or coil q located in
the storage-chamber X which the apparatus is designed to cool. Interposed
between the pipes q, q', is regulating mechanisms to be hereinafter described. The
return-pipe q³ from the refrigerating-coil extends downward through the top of the
trap or chamber E' terminating about half way between the top and lower end of
said chamber, as shown. Interposed in the pipe q3 is a valve q. Extending from
the top of the chamber E' to the induction-pipe or conduit s³, before mentioned, is
a pipe q. From the eduction-pipe or conduit extends an outlet pipe 73 which
passes through the top of the trap or chamber E2 downward, preferably to a point
about midway between the upper and lower ends of said chamber. Interposed in
the pipe is a valve . A pipe p extends from the top of the chamber E³ to the
chamber B where it communicates, as shown, with the condensing-coil B'. The
pipe p is provided with a valve pl. Communicating with the condensing-coil B¹ is
a pipe n which extends to the liquid-ammonia supplier or reservoir A'. Interposed
in the pipe n is a three-way cock n'. The chamber B is provided toward its lower
part, at one end, with a running-water inlet m, and at the upper part of its opposite
end with a water-outlet m¹.
The general operation of the mechanism thus far described is as follows:
Cold water is caused to enter the inlet m, fill the chamber B and run off at the
outlet m¹ to maintain the said chamber and the condensing-coil B¹ cool. In the
rotation of the drive-pulley D' the pistons C1, C2 are plunged up and down in
the cylinders C³, C, operating to draw fluid from the induction pipe and
discharge it into the eduction-pipe 2. The accumulated pressure in the eduction-
pipe passes through the pipe to the trap E2, thence through the pipe p and
condensing-coil B to the reservoir or supplier A¹ operating to force therefrom
liquid ammonia through the pipe q. At the end of the pipe q is a small port q
through which the ammonia is sprayed into a conduit of greater area, whereby the
ammonia is gasified in the pipe g' and coil g2 producing the well-known refrigerating
effect. From the coil g' the gas passes through the pipe q to the trap E', whence
it is drawn through the pipe q to the induction pipes. Thus in the operation of
the compressor a constant circulation is maintained.
The gas entering the trap E', from the return-pipe 9, is naturally very cold,
while, under the action of the compressor, the gas is heated to a comparatively
high temperature. For the purpose of lubricating the parts, the chamber C is
filled with a lubricating-oil to a level just above the top of the rock-shaft D'. It
is necessary in practice that no liquid ammonia shall pass through the induction-
pipe to the compressor, for the reason that the clearance at the pistons must
necessarily be but slight and the accumulation of liquid would tend to the injury of
the parts. It is also desirable that no oil should enter the compressor cylinders,
for the same reason, and also that no oil should pass with the ammonia through the
refrigerating-coil. When oil is allowed to enter the refrigerating-coil it tends to
clog the system and to coat the inner surface of the coil, and as oil is a bad
conductor of heat such a coating of the coil tends materially to lessen the
efficiency of the apparatus. The chambers E', E' form traps, as before described,
one interposed in the return conduit between the refrigerating-coil or conduit and
the compressor, and the other interposed between the compressor and the condensing-

page_text: I
coil. Any liquid ammonia and oil which may enter the trap El will necessarily be
caught in the trap while the gas is withdrawn through the pipe 9. Extending
from near the lower end of the trap E' is a pipe which leads to the chamber Cat
a point above the oil-level in the latter. Thus as oil and liquid ammonia accumulate
in the trap E¹ it will flow through the pipe to the chamber C. As the trap E¹ is
necessarily cold any liquid ammonia entering the same will tend to remain in the
liquid state, but when withdrawn into the chamber C it will meet a higher
temperature and becoming gasified will be returned to the system through
passages 3, cored in the cylinder walls and extending to the induction-pipes ².
The passages extend from the pipes & to points just above the lowest liinit of
the stroke of the pistons, and in the event that the valves s' should ever stick the
cylinders will fill through the passages s3. The shell E rests upon the top of the
chamber B and passes downward into the said chamber whereby the lower part of
the trap E2 is immersed in the cold water flowing through the chamber B. Gas
compressed by the pistons flows to the trap E' in a heated state, and it is afterward
liquefied under the cooling influence of the condensing-coil B. Any oil passing
from the eduction-pipe through the pipe will settle in the trap E2; and, as a
further precaution toward preventing oil from passing with the gas upward into
the pipe p, intermeshing deflectors & are provided in the chamber E2, as shown.
As the gas rises in the trap E2 from the pipe 3 it contacts with the surfaces of the
deflectors and these surfaces will tend to catch any particles of oil which the gas
may carry. As shown, the high-pressure and low-pressure traps are separated
from each other by a heat-conducting wall E³, which is subject on one side to the
cold of the trap E, and on its opposite side to the heat of the trap E'. Thus
through the wall the temperature of one trap influences that of the other, so that
their temperatures will always be kept within the bounds necessary for the perfect
working of the apparatus. A low-pressure trap when not subjected to the warming
influence of the high-pressure trap is apt, in practice, to generate frost and thus
become clogged; while a high-pressure trap when not subjected to the cooling
influence of the low-pressure trap is apt to become so hot as to tend to vaporize
oil lodging therein and render it impossible to prevent the oil from passing into
the system. These difficulties have been experienced in the past and have tended
to render refrigerating-machines of the small type inoperative. The construction
shown and described obviates the difficulties mentioned and make it possible to run
the machine indefinitely without any material quantity of oil entering the system,
and without any liquid ammonia entering the compressor-cylinders. It is to be
understood that this novel feature of the invention is of great importance.
Extending from near the bottom of the trap E2 up through the top of the latter
and thence downward into the top of the trap E' is a drainage pipe k¹ provided
with a valve k². Whenever oil is found to have accumulated in the base of the
trap E, the valve k may be opened, to open communication between the lower
part of the trap E' and the trap E', whereby the oil will be forced through the
pipe k into the trap E' and pass thence through the pipe into the chamber C.
Extending from the pipe q to the pipe is a pipe or by-pass i provided with a
normally closed valve . When, for purposes of repair or for other reasons, it is.
desired to empty the traps of all ammonia gas, in order that the gas may not be
wasted, the valves q, and p' may be closed and the valves k², may be opened.
This will cause the compressor to suck the gas from the trap E to the trap E
and thence through the pipe q, and discharge the gas through the pipe ³ and
by-pass i back into the pipe q and refrigerating-coil. The machine may be stopped
until the repairs are made.
g
At the end of the pipe q is a chamber in which a strainer is located. The
small port q is in the lower end of a shell or casing F and is shaped at its upper
end to form a valve-seat. In the shell are the tubular chamber h, chamber and
chamber 2. The chambers h, h' are in open communication with each other while
the chambers ', h² are separated from each other by a gas-tight movable abutment h³,
which is preferably in the form of a flexible diaphragm. Mounted between its

page_text: ends in the chamber h¹ is a lever h¹ pivotally connected at one end to a stem h
which is firmly secured to the center of the diaphragm h³. Extending downward
from the opposite end of the lever h is a stem carrying a valve h which seats
normally upon the port g. In the chamber or storage-room X is a casing G
containing a chamber g closed at one side by a gas-tight flexible diaphragm g¹.
Bearing against the outer surface of the diaphragm g¹ at the center thereof is an
adjustable set-screw g³. Also mounted in the chamber X is a casing G¹ containing
chambers separated from each other by a flexible gas-tight diaphragm f
Extending from the chamber g of the casing G to the chamber of the casing G¹
is a pipe G². The chambers f, g and pipe G2 are filled with a fluid, such as ether
or alcohol, which expands.and. contracts readily under changes of temperature, and
the pipe G2 should extend entirely around the storage-room X so as to be subjected
to changes of temperature in all parts of said room. The ether, or other fluid
employed, may be poured in at a filling opening f which is afterward tightly
closed with a screw-cap, and the fluid entirely fills the chambers f, g'and pipe G³.
Extending from the chamber f', of the casing G₁, to the chamber h², of the
casing F, is a pipe f'. The chamber f', pipe f and chamber h are completely
filled with a fluid, preferably hydrocarbon oil, which is poured in at the filling
pening, the opening being then tightly closed by means of a screw-cap.
In practice, the valve he tends to remain normally closed to shut off the supply
of ammonia from the pipe q. The fluid in the pipe G2 and chambers f, g form a
fluid thermostatic column which will expand and contract under changes in the
temperature of the room X. When it expands beyond a certain limit it presses
the diaphragm f' and fluid column in the chambers f¹, h² and pipe f, thereby
exerting pressure upon the diaphragm ³ to swing the lever I and lift the valve й®
from its seat. The operation of the thermostatic column may be regulated by the
set-screw g². Presuming, for example, that it is desired to maintain the temperature
of the room X at, say 30° F., the screw 2 is turned to compress the fluid
thermostatic column to a degree that will cause the latter, when the temperature
of the room rises above 30° F., to exert sufficient expansive force against the
diaphragm to press the fluid column in the pipe against the diaphragm h³
and open the valve h. When the valve he is opened, liquid ammonia from the
pipe will pass through the strainer q', the latter arresting any solid particles which
the ammonia may carry, and the ammonia will be sprayed through the port 9,
gasified and pass to the refrigerating-coil q2 to exert its refrigerating effect and lower
the temperature of the room X. When the said temperature falls below 30° F.
the contraction of the fluid thermostatic column will relieve the pressure
against the column in the pipe 1 and against the diaphragm, whereby the
valve will close. It will be understood that the valve he is capable of remaining
closed under the force of pressure from the pipe 9 and for this purpose a spring h
may be employed to press down upon the top of the stem of the valve h®.
9
His a casing having a tubular portion e in open communication with the
chamber and an oblong body-portion containing a chamber e¹. Extending across
the chamber el is a rib e, and the upper surface of the said rib and body-portion
form seats for two flexible diaphragms H1, H². On the body-portion is a frame H
sustaining a longitudinally extending screw e³. Mounted on the screw to travel
thereon is a block ; and fulcrumed between its ends upon the block is a
lever H pivotally connected at opposite ends to the centers of the respective
diaphragms H, H2. Connected with the diaphragm H' is a stem carrying a
valve e adapted to seat upon and close a port e in the tubular part e.
The object
of the mechanism shown at the casing H is to regulate the pressure of gas in the
coil by shutting off the inflow at the port e whenever the said pressure rises
above a predetermined limit, and to open the port e when the pressure in the coil
fails below a predetermined limit. In the drawings the diaphragms H', H' are
shown to be of the same size, although this is not necessary. Gas entering
through the port e will fill the chamber e and exert equal pressure against the
diaphragm H1, H2. Presuming, for purposes of illustration, that the ammonia

page_text: entering the tubular passage e has a pressure of 150 pounds to the square inch, as
indicated by the gage y, and it is desired to maintain the pressure in the coil gat
40 pounds to the square inch, as indicated by the gage y', the fulcrum e of the
lever H may be shifted by turning the screw e to cause the diaphragm H' to
move under pressure of 40 pounds in the chamber e and overcome the resistance
of the diaphragm H', supplemented by the resistance of the valve e, aud close
the latter. When the pressure in the chamber e' drops below 40 pounds the
pressure from the passage e against the valvo e will open the said valve. It will
be understood that the shifting of the fulcrum e lengthens or shortens the arm of
the lever H which is connected with the diaphragm H2, as compared with the arm
of the lever which is connected with the diaphragm H', and the desired adjustment
is effected by shifting the fulcrum of the lever so that when the pressure in the
chamber e rises above a predetermined limit the lever will be turned, by the
pressure moving the diaphragm H2 against the resistance of the diaphragm H'
and valve es, to close the valve; and when the pressure in the chamber e¹ drops
below the said predetermined limit, the pressure from the passage e against the
valve e will overcome the difference in pressure between the diaphragms H1, H2,
and the valve will be opened. The pressure regulator described is capable of very
fine adjustment and is exceedingly sensitive, so that the pressure of the gas in
the refrigerating-coil will always be maintained approximately equal.
The thermostatic governing mechanism described need only be employed where
an approximately even temperature is to be maintained in the room X, and it is
only in special cases where this will be desirable. Thus the pressure-regulator
may be employed either with or without a thermostatic governor and the
thermostatic governor may be employed with any other desirable form of
pressure-regulator.
Refrigerating-apparatus constructed throughout as shown and described embodies
all the features necessary for a most perfect apparatus capable of performing any
duty desired and within its capacity. As before stated, in certain connections the
thermostatic governing mechanism may not be necessary. The apparatus, as
shown and described, is the result of careful study and experiment, based upon
practical experience, and while it is preferred to provide all the parts as they are
shown and above set forth, it will be obvious that various details may be modified
without departing from the spirit of the invention as defined by the claims.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondents and in what manner the
same is to be performed, I declare that what I claim is :-
1. In a refrigerating-machine, a casing formed with a compartment for a liquid-
refrigerant reservoir, a condensing compartment, and a compartment surınounted
by cylinders and induction and eduction chambers, in combination with a motor,
compressors in the cylinders actuated by the motor, circulating conduits and traps
interposed in said conduits, substantially as described.
2. In a refrigerating apparatus, the combination with the liquid refrigerant
reservoir, the compressor, condenser and circulating conduit, of high and low-
pressure traps interposed in said conduits, the traps being so disposed with relation
to each other, that one will influence the temperature of the other, substantially as
and for the purpose set forth.
3. In a refrigerating apparatus, the combination with the liquid-refrigerant
reservoir, the compressor, condenser, supply-pipe, refrigerating-conduit, and return-
pipe, of a fluid-pressure regulator between the supply-pipe and refrigerating-conduit,
and traps interposed in said pipes, substantially as described.
4. In a refrigerating apparatus, the combination with the liquid-refrigerant
reservoir, the compressor, condenser, supply-pipe, refrigerating conduit, and return-
pipe, of a thermostatic governor and a fluid-pressure regulator between the supply-
pipe and refrigerating-conduit, and traps interposed in said pipes, substantially as
described.

page_text: 5. In a refrigerating machine, the combination with the compressor and its
induction and eduction-chambers, the condenser and the refrigerating-conduit, of a
return-conduit extending from the refrigerating conduit to the said induction-
chamber, a trap interposed in said return-conduit, a discharge-conduit leading from
said eduction chamber to the condenser, a trap interposed in said discharge-conduit,
and a heat-conducting wall separating the traps and operating as a means for
communicating the temperature of one trap to the other thereby modifying the
temperature of the other, substantially as and for the purpose set forth.
6. In a refrigerating machine, the combination with the compressor and its
induction and eduction chambers, the condenser and the refrigerating-conduit, of a
casing having two chambers separated by a wall and forming, respectively, a low
pressure trap and a high-pressure trap, a return-pipe leading from the refrigerating-
conduit into the low-pressure trap, a pipe connecting the low pressure trap with the
said induction-chamber, a pipe leading from the high-pressure trap to the condenser,
and a pipe leading from the eduction-chamber into the high-pressure trap, substan-
tially as described.
7. In a refrigerating-machine, the combination with the shaft-chamber, the
compressor and its induction and eduction chambers, the condenser and the
refrigerating-conduit, of a return conduit extending from the refrigerating-conduit
to the said induction-chamber, a low-pressure trap interposed in said return-conduit,
an outlet conduit leading from the said eduction-chamber to the condenser, a high-
pressure trap interposed in the said outlet conduit, a heat-conducting wall
separating the traps and operating as a means for communicating the temperature
of one trap to the other thereby modifying the temperature of the other, a drainage-
pipe provided with a valve and extending from the lower part of the high-pressure
trap into the low pressure trap, and a pipe extending from the lower part of
the low-pressure trap to the shaft-chamber, substantially as and for the purpose
set forth.
8. In a refrigerating-machine, the combination, with the shaft-chamber, the
compressor and its induction and eduction chambers, the condenser and the
refrigerating conduit, of a casing having two chambers separated by a wall, and
forming, respectively, a low-pressure trap and a high-pressure trap, a return-pipe
leading from the refrigerating-conduit into the low pressure trap, a pipe connecting
the low pressure trap with the said induction-chamber, a pipe leading from the
high-pressure trap to the condenser, a pipe leading from the said eduction-chamber
inta the high-pressure trap, a pipe provided with a valve and extending from the
lower part of the high-pressure trap to the low-pressure trap, and a pipe extending
from the lower part of the low-pressure trap to the shaft-chamber, substantially
as and for the purpose set forth.
9. In a refrigerating machine, the combination, with the compressor and its
induction and eduction-chambers, the condensing-chamber and the refrigerating-
conduit, of a casing having a chamber forming a low-pressure-trap and a chamber
extending downward into the condensing-chamber and forming a high-pressure
trap, a return-pipe extending from the refrigerating conduit into the low pressure
trap, a pipe leading from the upper portion of the low-pressure trap to the said
induction-chamber, a pipe extending from the said eduction-chamber into the lower
part of the high-pressure trap, and a pipe extending from the upper part of the
high-pressure trap to the condensing-chamber, substantially as and for the purpose
set forth.
10. In a refrigerating-machine, the combination with the compressor and its
induction and eduction-chambers, the condensing-chamber and the refrigerating-
conduit, of a casing having a chamber forming a low-pressure trap and a chamber
extending downward into the condensing chamber and forming a high-pressure trap,
a return-pipe extending from the refrigerating-conduit into the low-pressure trap,
a pipe leading from the upper portion of the low-pressure trap to said induction-
chamber, a pipe extending from the said eduction-chamber into the lower part of
the high-pressure trap, deflectors in the high-pressure trap between the outlet from

page_text: said pipe and the top of the trap, and a pipe extending from the upper portion of
the high-pressure trap to the condensing-chamber, substantially as and for the
purpose set forth.
11. In a refrigerating apparatus, a fluid-pressure regulator, having a valve-
operating mechanism, comprising pressure-actuated, differentially moving, co-acting
diaphragms connected with the valve-stem, whereby the valve is operated by
differentiation due to accumulation of pressure, substantially as described.
12. In a refrigerating apparatus, a fluid-pressure regulator, having a valve-.
operating mechanism, comprising in combination with the valve, diaphragms
receiving uniformly the fluid-pressure, and a lever connection at sail diaphragms
and valve affording a differential leverage, whereby on accumulation of pressure a
power sufficient to operate the valve is obtained by differentiation of movement of
the diaphragm, substantially as described.
13. In a refrigerating apparatus, a fluid-pressure regulator, having a valve-
operating mechanism, comprising in combination with the valve, diaphragms.
receiving uniformly the fluid-pressure, and an adjustable lever-connection at said
diaphragms and valve affording a differential leverage, whereby on accumulation.
of pressure a power sufficient to operate the valve is obtained by differentiation of
movement of the diaphragms, substantially as described.
14. In a refrigerating apparatus, a fluid pressure regulator, comprising in.
combination, a chamber or casing having an inlet-port from the supply-pipe and
an outlet to the refrigerating conduit, separate diaphragms at said chambers.
differentially movable under pressure therein, a valve at said inlet-port connected
with one of said diaphragms, and a lever connection between the diaphragms.
adjustable to change the relative resistance of the diaphragms against movement.
under pressure in the chamber, substantially as and for the purpose set forth.
15. In a refrigerating apparatus, a fluid-pressure regulator, comprising, in
combination, a chamber or casing having an inlet-port froin the supply-pipe and
an outlet to the refrigerating-conduit, separate diaphragms at said chamber
movable under accumulated pressure therein, a valve at said inlet-port connected
with one of said diaphragms, a lever-connection at opposite end-portions with the
respective diaphragms, and a screw-actuated sliding-block mounted upon the casing
and affording a shifting fulcrum for the lever between the ends of the latter,.
substantially as and for the purpose set forth.
16. The combination with a refrigerating-conduit and a storage-chamber through
which the conduit passes, of a passage between the liquid-refrigerant supplier and
refrigerating-conduit, a valve at said passage, and thermostatic mechanism in said
chamber communicating with the said valve and operating under rise of temperature
in said chamber to produce opening movement of the valve, substantially as and.
for the purpose set forth.
17. The combination with a refrigerating-conduit and a storage-chamber through
which the conduit passes, of a passage between the liquid-refrigerant supplier and
refrigerating-conduit, a valve at said passage, valve-opening mechanism and a
fluid thermostatic column in said chamber communicating with said valve-opening-
mechanism and operating under rise of temperature in said chamber to produce
opening movement of the valve, substantially as and for the purpose set forth.
18. The combination with a refrigerating-conduit and a storage-chamber through
which the conduit passes, of a passage between the liquid-relrigerant supplier and
said conduit, a valve at said passage, a fluid-thermostatic column in said chamber
communicating with the said valve and operating under rise of temperature in
the said chamber to produce opening movement of the valve, and regulating
means for the said thermostatic column, substantially as and for the purpose.
set forth.
19. The combination with a refrigerating conduit and a storage-chamber through.
which the conduit passes, of a passage between the liquid-refrigerant supplier
and said conduit, a movable abutment at said passage, a valve in the said passage
operatively connected with the said abutment, a fluid thermostatic column in the

page_text: said chamber, a movable abutment at said thermostatic column, and a fluid-
column confined between said movable abutments, whereby in the expansion of
the thermostatic column pressure is exerted through the abutments and intervening
column to produce opening movement of the said valve, substantially as and for
the purpose set forth.
20. The combination with the refrigerating-conduit and a storage-chamber
through which the conduit passes, of a passage between the liquid-refrigerant
supplier and said conduit, a movable abutment at said passage, a valve in the
said passage operatively connected with the said abutment, a fluid-thermostatic
column in the said chamber, movable diaphragms between which the said thermo-
static column is confined, adjusting means at one of said diaphragms operative to
increase and diminish the pressure of the diaphragms against the column, and a
fluid-column confined between the other said diaphragm and the said valve-
operating abutment, whereby in the expansion of the thermostatic column pressure
is exerted thereby through the said fluid-column against the said abutment to
produce opening movement at the said valve, substantially as and for the purpose
set forth.
1000
BOULT & WADE,
Agents for the Applicant.