Improvements in Refrigerating-machines.
Year: 1892

page_text: Date of Application, 26th Sept., 1892-Accepted, 11th Feb., 1893
COMPLETE SPECIFICATION.
Improvements in Refrigerating-machines.
I, CHARLES FREDERICK MILLER, a citizen of the United States, residing at
42 East King Street, in the City of Lancaster, County of Lancaster, and State of
Pennsylvania, United States of America, Manufacturer, 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 improvements in refrigerating-machines, and especially
to those operated by absorption.
It consists, partly, in the combination of a generator with a jacketed extension of
the same having a coil therein, the said jacket and coil being supplied with cold
water to condense the steam which ascends with the generated gas, in order to
dispense with a separate dehydrator, or the said coil may be arranged in the
jacketed upper part of the generator itself.
In the accompanying drawings,
Figure 1 represents a vertical section of the refrigerating apparatus embodying
my invention.
Figure 2 represents an enlarged detail view, in vertical section, of one of the
generators, the extension, the coil therein, and the perforated shells between the
said generator and the said extension, the arrangement of the pipe-outlets being
changed.
Figure 3 represents a vertical section of the upper end of the generator having
the coil D therein and without the extension C.
Figure 4 represents a horizontal section of the same on the line x-x of
Figure 3; and
Figure 5 represents a detail view of the top of the generator, with a pair of
flanges for each shell.
A and B designate the two generators of my apparatus, which are counterparts
in construction, preferably cylindrical, and contain aqua-aumonia. Each of these
generators is provided with a heating and cooling pipe u or bin helical form, the
upper ends of these pipes being connected by two cross pipes a' b', the former of
which is supplied with steam through a pipe a² and the pipe b with cold water
through a pipe b. Valves 1 and 2 on each side of pipe a² in pipe a' allow steam to
be turned into or cut off from either of the pipes or coils a 6 at will. Valves 3
and 4, similarly situated in pipe &', likewise control the flow of cold water into the
said pipes or coils. These valves are opened and closed by hand, the valve 1 being
always open to discharge steam into coil while the valve 4 is open to discharge
cold water into the coil a and the valve 2 being open to discharge steam into the
coil when the valve 3 is open to discharge cold water into the coil a.
instance the valves not mentioned as open are closed. By the above arrangements
one generator is heated for giving off the gas, while the other is cooled for
absorbing it.
In either
As shown in Figures 1 and 2, a cylindrical extension C, preferably of less
diameter than the generator, is formed on or attached to the top of the latter in
each instance and provided with a bollow water jacket C", having an inlet c and an
outlet c' for cold water. A coil of pipe D is arranged within this extension, having
its outlet end d passed through the said jacket. The two coils D are supplied
through pipe 62 aforesaid and branch pipes d', the latter being controlled by valves d².
The steam which is carried up with the gas from the generator is cooled and con-
densed by the action of the water in the jacket C¹ and coil D and falls back into
the generator.

page_text: To prevent foam from passing up with the gas into the said extension, I make
use of two or more perforated shells E, preferably flat or concavo-convex, as shown,
which are held at their peripheries by flanges e, arranged in pairs above and below
the said shells around the openings in the tops of the said generators. These shells
and flanges may be arranged either as shown in Figure 3-that is to say, with all
the shells between a single pair of flanges-or, as shown in Figure 5, with each
shell between a pair of flanges used for it alone. These shells, being made of thin
elastic metal, may easily be sprung into position between the flanges. The per-
forations in these shells allow the water to drop through them, but are not large
enough to permit the foam to ascend through them. As shown in Figures 3 and 4,
the coil D in each instance may be put within the upper part of the generator and
the jacket C around the said upper part instead of employing the extension C ;
but the extension is preferable.
From the top of the interior of each extension or directly from the top of the
generator when no extension is employed a pipe f extends upward, provided with a
cut off valve for f2, the former for the gas from generator A, the latter for that
from generator B. These pipes unite in a pipe F, which forms a coil G within a
condenser H, the latter being a casing having cold water circulated through it by
means of an inlet h and an outlet h¹. A continuation G¹ of the said pipe and coil is
provided with two branch pipes II', the former provided with a cut-off cock or
valve i and the latter with a cut-off cock or valve. The pipe I supplies a liquid
storage tank J and the pipe I' a liquid storage tank J. Outlet pipes k from these
tanks are provided with valves kk2 and unite in a pipe K, which runs to the
refrigerating coil L, preferably arranged in a chest or chamber where cooling is
desired. A valve K¹ in the said pipe K regulates the supply of the refrigerant as
it expands into the said coil. From this refrigerating coil a pipe M, controlled by
a valve m, runs to a pipe N, which through branch pipes n, controlled by cut-off*
valves, supplies the exhausted gas to either one of the generators. The
generator thus supplied at any time is always that which is then being cooled and
absorbing. A check-valve O in pipe N prevents the gas from escaping back to the
refrigerating coil.
Q designates a brine box having within it a refrigerating coil R, which is
connected at the inlet end by a pipe ", controlled by a cut-off valve r', to the pipe K
below the valve K' and at its outlet end by a pipe s controlled by a valve s', to the
pipe N aforesaid. The opening of the valve allows the refrigerant to expand as
gas into the said coil R with the usual chilling effect. When the valves r¹ and st
are open, the said brine box is in the refrigerating circuit.
The operation is as follows: The generator A being heated by the flow of steam
through the coil a, as described, the gas passes up through the open valve f' to the
condenser, and thence through the pipe and valve to the storage tank J, where
under its own pressure and the cooling action of the said condenser it assumes a
liquid form. There it remains until allowed to flow out by opening valve k' for
refrigerating purposes. When it is thus drawn off, the gas flows through the
refrigerating-coil L, the valve K₁ being opened to the extent desired, and thence
through pipes M N and valves m n' to the generator A, whence the gas was given
off.
During this flow from the storage tank J back to the generator A the latter
is cooled by the flow of cold water through the pipe or coil a and the aqua-ammonia
within the said generator absorbs the spent ammonia-gas thus supplied. Thus the
generator is its own absorber also. At the same time that the cold water is let
into the coil a steam is admitted, as before explained, into coil b. The gas is given
off by generator B through valve f2 and through the condenser H and valve ¹ to
storage tank J. There it remains as liquid until the charge is withdrawn from
tank J, when the outlet valve k', before described, is closed and the outlet valve k²
is opened. The liquid refrigerant then flows from tank J' through the refrigerating
coil, following the course of the previous charge from J and expanding into gas
within the said coil for refrigerating action, as stated. From said coil it flows

page_text: through pipes M and N and valves m and n² into the generator B. Of course at
the time the charge from tank J is set free for refrigeration the steam is turned
again into coil a and the cold water into coil b of the generators A and B,
respectively. There are thus two plants, each with its own charge of ammonia, its
own generator, which also acts as absorber, and its own liquid storage tank, but
having in common the condenser, the refrigerating coil, and some connecting pipes.
The charges need never mingle if the gas given off by generator A be all received
as liquid in the storage tank J before that given off hy generator B is admitted to
the pipe F and the condenser and if the refrigerant supplied by the tank J' be all
absorbed by the aqua-ammonia in generator B before the charge is set free from
tank J, the corresponding action, and arrangement of the complementary parts
being understood in both cases.
The extensions C of the generators, with their cold water coils, and cold water
jackets, do away, unless under exceptional circumstances, with the necessity for a
separate dehydrator or additional steam separator in common, the condensation of
aqueous vapor being very complete as the said vapor ascends between the cold coil
and the cold jacket.
Each extension C is preferably a piece of wrought-iron pipe screw-threaded at
its lower end and screwed into the similarly-screw-tapped top or cover B₁ of the
generator. This top is itself screw-threaded on its internal periphery and screwed
on the externally-screw-threaded upper end of the generator. The joint between
the said cover and generator is made gas-tight by a packing ring B³, which is com-
pressed by a follower or clamping-ring B2, this last being fastened to the said cover
by screws B₁. A similar packing-ring B' is used with the joint between the
extension and the generator in each instance, and screws Be are employed as
additional means of fastening the former to the latter.
T designates a hood or shell within which a coil of pipe t is subjected to the
action of heat from a fire arranged below the said coil or by any other suitable
means, the heated air and products of combustion finally escaping through an
outlet-flue 2 of the said hood or shell. Both ends of the pipe t connect with the
generator A, the one at a higher point than the other. The upper end is provided
with a valve t' and the lower with a valve 2. The generator B is similarly con-
nected to the ends of the coils by pipes U and U', controlled by valves u u. By
means of this coil and connections and the heating agency applied to it the contents
of one generator may be thoroughly heated to a high degree for giving off gas
while the other generator is being cooled for absorbing.
My system of plants, independent, though connected, has this great advantage,
that if either plant becomes in any way disabled, as by leakage developing in the
generator or storage tank, the other plant may be used alone, so that there need
never be any cessation of the supply of ice or cold air; but ordinarily the two
plants or series of devices having the condenser and refrigerating coil in common
are used in rapid alternation, as above stated.
The coil t and the other devices connected therewith or relating thereto for
keeping up a circulation of ammonia-gas through the generators need not be used,
except on special occasions.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. In combination with a generator of volatile refrigerant, a cooling-coil and a
cooling-jacket exterior to said coil, the two cooling devices being arranged to allow
the gas to flow out between them, while the steam accompanying it will be
condensed and precipitated, substantially as set forth.
2. In a refrigerating-machine, a generator provided with an extension C of less
diameter, in combination with a cooling-jacket C₁, applied to this extension only,
an inlet and outlet for water to circulate through the said jacket, and a coil for

page_text: cooling water arranged within the said extension only, this extension communicating
at bottom with the interior of the said generator and having in its top an outlet for
gas, substantially as set forth.
Dated this 16th day of August 1892.
CHARLES FREDERICK MILLER,
By his Agents, Carpmael & Co.