Improvements in or relating to Refrigerating or Cooling Machines.
Year: 1895

page_text: Date of Application, 5th Nov.. 1895-Accepted, 11th Jan., 1896
COMPLETE SPECIFICATION.
Improvements in or relating to Refrigerating or Cooling Machines.
A communication by ALEXANDER T. BALLANTINE, of Cleveland, in the County
of Cuyahoga and State of Ohio, United States of America, Mechanic.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6 Bank Street,
Manchester both in the County of Lancaster, 118 New Street, Birminghamı in
the County of Warwick and 31 High Holborn in the County of Middlesex,.
Civil 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:-
The invention consists in an improvement in cooling machines hereinafter fully
described and claimed.
.
Figure 1 is an elevation of the complete machine except the motor, and Figures 2,
3, 4 and 5 are vertical central sections through the governing valve.
In one known type of machine for refrigerating by the expansion of a volatile liquid,
such as anhydrous ammonia, the cooling effect is produced by permitting liquid
ammonia, which is at high pressure, to expand in the form of gas into a refrigerating:
coil, drawing the expanded gas from the refrigerating coil and compressing it by.
means of a pump, cooling by water and permitting it again to expand into the
refrigerating coil.
It is evident that the continuance of this operation requires first that the pump
must be kept in operation, and second that the refrigerating (or expansion) coil
must at all times contain expanded gas.
My correspondent's experience with this class of machines leads him to believe
that the second requirement cannot be automatically met by either a valve set to
admit a steady regulated feed, or by a valve intended to maintain a constant
pressure in the expansion coil, such as pressure regulating valve, or teinperature
regulating valves, because the small orifice necessarily employed soon clogs up
(probably with some saponaceous substance), and because of their liability to flood
the expansion coil with ammonia, nor by a positively driven intermittent feed, as
by a valve operated from the moving parts of the pump, because of the irregular
action of gas pumps working against pressure.
My correspondent has discovered that by admitting a jet or spurt of ammonia to
predetermined
the expansion coil when the pressure in said coil is reduced to a
limit, and then closing the feed valve until the pressure is again reduced to said
limit, a machine of this class can be made which is automatic, namely, which will
operate continuously so long as the pump is kept in motion.
P represents a pump having cylinders p p, which is driven by power applied to
a rock shaft R. O represents the discharge pipe of said pump, S a box containing
a condensing coil and tank connected with pipe O; B a pipe connected with said
tank, and a refrigerating or expansion coil connected at one end, through
governing mechanism embodying the invention, with pipe B, and at the other end.
with the casing of pump P.
All these parts, except the governing mechanism, may be of any suitable
construction, and do not need detailed description.
A governing mechanism embodying one, and what is now believed to be the best
form of the invention is represented in section in Figures 2 and 3, aud is as follows,

page_text: and for the sake of brevity the compression side of the system will hereafter be
indicated simply as "pipe B" and the expansion, or refrigerating side of the system
simply as "pipe C."
The
A represents a tube or valve casing closed at its lower end by a head D, into
which tube through a boss 2 leads the pipe B, and out of which through a boss 3
leads the pipe C, the joints of these connections being made gas tight.
pipe B is closed at its inner end, and on its under side is formed a small orifice 4,
which serves as a feed or supply port and a valve seat to receive and be closed by
a needle valve F. This needle valve F is carried in a yoke G, as illustrated, (but
of course may be guided and carried in any other suitable way), the yoke G
encircling a portion of the pipe B, being an easy way to adjust this mechanism.
H represents a valve stem, which passes through and is connected with a flexible
diaphragm E, which closes the upper end of the tube A, and above this diaphragm
is pivoted on pin 8 a lever L, resting on the top of the valve stem H, and provided
with an adjustable weight M, by which the pressure of said lever on the valve
stem may
be regulated. The weight of the valve may take the place of this lever,.
but the lever or a spring is preferable.
It will be noticed that diaphragm E is slightly arched, its shape in Figure 4
being practically identical with that of the spring bottom of an oil can, and in
Figures 2 and 3 being an upwardly extending flat arch. This not only gives the
diaphragm a sufficient play, even under considerable variations of form, so that
the valve, when it opens may open wide, but this form of diaphragm offers
greater resistance to, or works more effectively against, the pressure of the
lever L when it is at its highest working point, that is when the valve is closed,
than at any lower working point, so that when the valve is closed, the spring
action of the diaphragm will so reinforce the gas pressure as to hold the valve
closed even when the gas pressure on the under side of the diaphragm, as it
becomes reduced or lessened, is insufficient, by itself, to do so.
The result is that when said diaphragm is pressed down, it will open the valve
which it governs fully and quickly, and when it is pressed up will close the
valve and hold it closed until the gas pressure is sufficiently reduced.
סו
In Figures 2 and 3 is shown valve F arranged to close against the pressure
pipe B, and having its area made so small in comparison with the area of
diaphragm E that the pressure on said valve may be neglected, or rather may
be treated as a mere additional weight to be raised and sustained by the
pressure on diaphragm E and the spring action of said diaphragm.
If, however, the action of valve F be reversed, that is, if it be made to close
with, and open against the pressure in pipe B, as shown in Figure 5, then the
effect of said pressure.in forcing said valve to its seat and holding it there, will
reinforce the gas pressure on said diaphragm, and will in some cases be sufficient
(when the area of the valve and valve stem is large enough) to entirely take the
place of a spring diaphragm and permit the use of any form of diaphragm which
is sufficiently flexible.
The operation of the invention is as follows:
The structures of Figures 2, 3 and 4 will first be considered-
Assume that a gas pressure of 15 lbs. to the square inch on the under side of the
diaphragm E, in addition to the resiliency of the diaphragm itself, is required to
close valve F, when once open.
Assume that valve F is closed, and there is a gas pressure of 15 to 20 lbs. to the
square inch on the under side of diaphragm E.
In this case the pressure of the weighted lever L tending to open said valve is
resisted first by the gas pressure on the under side of diaphragm E, and second by
the resistance (not merely the resilience) of the arched diaphragm. The effect of
arching the diaphragm is to cause it to offer a greater resistance to lever L, when
in its normal form, than when deformed. This may easily be tested by pressing
on the arched bottom of an ordinary spring bottom oil can, when it will be found
that more pressure is required to start the arched bottom inwards than to press it

page_text: further in when started, or to hold it pressed in. Of course both diaphragm E
and the spring bottom of an oil can tend by their resilience to return to their
normal form when deformed, but this resilience is present in every position of the
diaphragm, and may be treated as merely an additional elastic force added to, and
acting in unison with, the gas pressure on the under side of the diaphragm.
Under these conditions, the action of the pump, P, drawing gas from C, is to
reduce the gas pressure on the under side of diaphragm E. If the apparatus
were an ordinary pressure regulating valve, such as is shown in any of the Patents
above cited, as soon as the gas pressure in C becomes reduced just below 15 lbs.
to the square inch, valve F would open slightly and assume such position as to
permit liquid to pass through orifice 4 just fast enough to maintain a constant
pressure of 15 lbs. to the square inch in C. But the apparatus does not work in
this way. When the gas pressure in C is reduced just below 15 lbs. the valve
remains closed because of the resistance (not merely the resilience) of the arched
form of diaphragm.
Assume that this arch or resilient resistance of whatever kind it be, is equal in
its effect upon lever L to a gas pressure of three pounds to the square inch on the
under side of diaphragm E.
:
Valve F will remain tightly closed until the gas pressure in C is reduced to
12 lbs. to the square inch, when lever L will overcome the resistance of the gas
pressure in C on diaphragm E plus the "arch" or other resistance of the diaphragm
and start the diaphragm inwards. This instantly eliminates this particular
resistance of the diaphragm leaving only the gas pressure in C plus the normal
resilience of the diaphragm, to oppose lever L, and the valve F is instantly
opened wide. A portion of the liquid in pipe B instantly spurts violently through
orifice and raises the pressure in pipe C to 15 lbs. to the square inch, or more,
and this pressure, acting on the under side of diaphragm E, forces said diaphragm
upwards and closes valve F. The valve now stays closed until the pump again
reduces the pressure in pipe C as before, when the action above described is
repeated.
If the valve F be made to close with the pressure in pipe B, and a diaphragm
be used which has no "arch" action, and even no resilience, the operation is as
follows:
As one end of the valve stem is subject to the pressure in pipe B, there is
always an unbalanced pressure equal to the pressure in B over atmospheric
pressure tending to close valve F, but as this is a constantly acting force it
may be neglected, just as in the previous description the resilience of the diaphragm
was neglected..
'
Assuming the same conditions as before, with valve F closed and a gas pressure
of 100 lbs. in pipe B, it is evident that the tendency of lever L to open the valve
is resisted by the gas pressure in C on diaphragm E, the unbalanced pressure on
the lower end of the valve stem, and by the unbalanced pressure on so much of the
under side of the valve F as equals the area of orifice 4 minus the area of the valve
stem (which area will hereafter be called tbe valve area for brevity) and this
unbalanced pressure is the difference between the pressures in B and C. The
second factor will now be disregarded in describing the operation:
When the pump has reduced the pressure in C to 15 lbs. the weighted lever L
will be resisted by a pressure of about 85 lbs. to the square inch on the valve area
in addition to the gas pressure on diaphragm E and valve F will remain closed..
As the pump continues to reduce the pressure in C these two forces will hold the
valve closed until their sum becomes of less effect than a gas pressure of 15 lbs. to
the square inch on diaphragm E, when lever L will force the valve F open. As
soon as the valve opens at all, the unbalanced pressure on the valve area is reduced,
and the valve opens wide. A portion of the liquid in pipe B instantly spurts
violently through orifice 4 and raises the pressure in pipe C to 15 lbs. to the square
inch or more, and this pressure acting on the under side of diaphragm E forces,

page_text: said diaphragm upwards and closes valve F. The instant the valve closes the
unbalanced pressure on the valve area again comes into play, and the above
described operation is repeated.
When the valve of Figure 5 is used with the diaphragm of Figures 2, 3 and 4,
both the "arch" action and unbalanced pressure on the valve area
utilized.
can be.
The mechanism shown in Figures 3 and 4 is preferred to that shown in Figure 5,
because with the arched diaphragm, the downward "arch" resistance of the
diaphragm can be utilized to the closing of the valve by so arranging the
mechanism that the diaphragm, when the valve opens, springs down beyond
the centre line and arches downward, thus affording a resistance to closure of the
valve similar to its resistance to opening.
The mode of operation is therefore analogous to what would occur if valve F
were arranged to be opened and closed by hand and an engineer should watch a
gauge on pipe C, and, when the pressure therein was reduced to a predetermined
amount, should open the valve, admit a spurt of liquid to pipe C, and then close
the valve; wait till the pressure in C was again reduced to the determined amount,
and again open and close the valve. But it differs in the important particulars
that the apparatus is automatic, is much quicker in its operations than a manually
operated valve would be, and is always ready when the appointed time arrives.
While it is preferred to use a weight or spring for the force which tends to open
the valve because of cheapness of construction and ease of adjusting them to the
varying limits of expansion in C which may be required for different situations
where varying degrees of temperature are desirable, it is evident that any other
positive force may be substituted for the weighted lever or its equivalent, a spring.
In the invention the most important feature is the mode of operation, and the
particular forces employed are of secondary importance, though there is room for
selection on this point in the line of economy, simplicity, ease of adjustment and
durability, and all mechanisms of like function, which will do the work under the
described conditions of use, are included herein as mechanical equivalents.
It will be thus seen that the action of the pump governs the admission of
ammonia into the expansion coil, and that if the pump is irregular in its action,.
and occasionally misses one or more strokes, which is usually the case with gas
or air pumps working against pressure, the feed is correspondingly irregular, and
valve will wait until the pump has caught up with its work. This mode of
operation gives the additional incidental advantage that only a small part of the
expansion of the ammonia occurs in the valve, where it is injurious, and the bulk
of the expansion occurs in the refrigerating coil, where it is needed, while with a
pressure regulating valve, or a temperature regulated valve (during the short time
which elapses before they clog up), the expansion is mainly at the valve, and
freezes the clogging deposits as fast as it forms.
In practice the valve opening mechanism is so regulated that the valve will open
when the pressure in the refrigerating coil (C) falls to the point which corresponds
exactly or approximately to the expansion desired for the work to be done.
It will be noticed that in Figure 2 the said tube B has its sides flattened to serve
the better as a guide for said yoke, and the said yoke is suspended from the
diaphragm E by a rod H which passes through the centre of the diaphragm and is
threaded in the yoke so as to be adjustable. Now, in order that this valve F may
key
be adjusted by the attendant or operator, so as to set it at any desired point, a
rod K may he employed, which passes up through the centre of the head D and is
packed therein to avoid leakage, and has its upper end constructed to engage in au
open slot in the head 6 of the valve F. The lower or outer end of rod K is
80, if the
constructed to be engaged by a wrench or other device to turn it, and
valve F requires setting, the operator can reach it through this rod K and turn it
freely as if he could reach the rod itself, directly, by a suitable turning instrument.
This loose construction of the valve head 6 enables the valve to have the necessary

page_text: up and down movement responsive to the diaphragm E without in any manner
disengaging it from the key rod K, and hence without changing the position of
said valve.
My correspondent has shown a construction of diaphragm, and type of valve,
which he likes very much, but wishes to have it understood that his invention is
not confined to these forms, as he believes that he is the first man to substitute an
automatic intermittent irregular jet or spurt feed for a regular feed in a machine
of this class, and therefore the first to produce an automatic machine which will
operate without attention so long as the pump runs.
It is found that, while the valve closing with the pressure in B (Figure 5) can
be used with any form of diaphragm which is sufficiently flexible, it works very
nicely with the arched resilient diaphragm shown in the other figures.
It is evident that when the principle of the machine is stated to good mechanics,
various mechanical structures can be made differing in form and appearance from
those which have been chosen to illustrate the invention, but adapted to do the
same work, on the same principle, for instance in place of a diaphragm a movable
abutment may be employed, as will be readily understood.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. In a refrigerating or cooling machine, the combination of a pump, a compression
coil, an expansion coil, an intermittently operating feed valve intermediate between
the two coils, a movable diaphragm or abutment subject to gas pressure on the
opening of the valve, for reclosing it, a suitable mechanism (as a spring, weight, or
equivalent pressure) acting in the same direction as such. gas pressure and acting
with greater effect when the valve is closed than when the valve is opened, and a
suitable power applying mechanism (as a weight, spring or equivalent pressure)
normally constant in amount, for opening the valve, substantially as set forth.
2. In a refrigerating or cooling machine, the combination of a pump, a compression
coil, an expansion coil, an intermittently operating feed valve intermediate between
the two coils, a movable diaphragm or abutment subject to gas pressure, on the
opening of the valve, for reclosing it, a suitable power applying mechanism (as a
weight, spring, or equivalent pressure) for opening the valve, and a counteracting
mechanism (as a spring, weight or equivalent pressure) suitably arranged and
adjusted in amount and direction for partially neutralizing when the valve is closed,
the effect of the opening mechanism, such neutralizing mechanism becoming
practically inert or inoperative on the opening of the valve, substantially as set
forth.
3. In a refrigerating or cooling machine, the combination of a pump, an expansion
coil, an intermittently operating feed valve intermediate between the two coils, a
movable diaphragm or abutinent subject to a variable gas pressure operative in a
suitable direction for scating the valve, a suitable pressure applying mechanism
supplementary thereto, and operative in the same direction, but with an increasing
effect or force when the valve comes to its seat, and a suitable power applying
mechanism, (as a weight, spring or equivalent pressure,) for opening the valve,
substantially as set forth.
4. In combination with the compression chamber and the expansion chamber of
an ammonia refrigerating or cooling machine, a valve located between said chambers,
having an arched resilient diaphragm, subject to the pressure. in the expansion
chamber tending to close said valve, and a weight or spring tending to open said
valve.
Dated this 4th day of November 1895.
WM. P. THOMPSON & Co.,
Agents.