IMPROVEMENTS IN MACHINES FOR MAKING ICE, COOLING LIQUIDS, REFRIGERATING ROOMS, AND FOR OTHER LIKE PURPOSES
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the
Office of the Commissioners of Patents, with his Petition, on the
24th July 1872.-A communication from abroad by Samuel B.
Martin, and James M. Beath, both of San Francisco, California,
United States of America.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN MACHINES FOR MAKING
ICE, COOLING LIQUIDS, REFRIGERATING ROOMS, AND FOR OTHER LIKE PURPOSES," a
communication, to be as follows:-
-
This Invention relates to that class of machines in which cold is
continually produced by the vaporization, liquefaction, and return for
continuous use of a volatile fluid acting directly on the substance to be
frozen without the intervention of a non-congealable liquid. It consists
of three parts or divisions common to all such machines, namely, a
congealer, compressing pump, and condenser. As the most important
part of the said Invention relates to the congealer I will first briefly
refer to the principle on which this part of the said Invention is based
in order that it may better appear wherein the same differs from all
others before known or used.

page_text: It will be apprehended by those skilled in the arts to which the said
Invention belongs, that the withdrawal of heat from water in quantity
sufficient to produce ice in bulk by the vaporization of a volatile liquid
contiguous to it, involves either a rapid transmission of heat from the
water to the liquid, or the action must be spread over a large surface.
As ice is a slow conductor of heat, and as the heat withdrawn has to
pass through the ice already formed, a rapid freezing of ice of any
considerable thickness is impracticable and can only be partially urged
by vaporizing the liquid at an extremely low temperature, and con-
sequently low pressure, which can only be accomplished by an
unwarrantable expenditure of power. Therefore a uniform distribution
of both the volatile liquid and the water over a large surface is a
condition indispensable to the production of ice with economy, and its
consequent slow formation is essential in producing it in solid and
transparent form from undistilled water.
Heretofore the method of freezing by direct contact has been by
spraying the liquid within the freezing surface, by covering the inner
surface of the freezing vessel with absorbents of the liquid or by means
of expansion chambers, and more recently by means of hollow slabs or
long and narrow chambers holding a specific charge of liquid sufficient
by its vaporization to give a stated result or freeze a given quantity of
ice on the surface of the containing vessel. But the vaporization of any
liquid offering free space for the escape of the vapor or gas from the
surface of the liquid will necessitate the absorption of nearly all its latent
heat before leaving the surface of the liquid; therefore the constant
subsidence of the liquid as it passes off in the gaseous state will inevitably
produce an irregular formation of ice. Moreover the machines here-
tofore in use are from the nature of their construction practically limited
in size so that in a manufactory of any considerable extent they require
to be duplicated.
To avoid these and other objectionable conditions, experiments have
been made from which it has been discovered that when volatile liquids
are vaporized in their passage through long channels or pipes of small
sectional area, the liquid particles are carried along by the moving vapor
without reference to grade, and may be made to produce nearly a
uniform freezing temperature throughout their length by simply
adjusting the pressure in the said pipes so that all the liquid particles
are vaporized by the time they reach the outlet.

page_text: By taking advantage of this movement of liquid and vapor together,
the pipes may be laid horizontally, however long they may be, and by
encasing them in metallic plates at a suitable distance apart an
immensely large surface may be economically produced capable of
freezing transparent ice of uniform thickness from water resting against
its sides.
The aforesaid congealer consists of vertical metallic plates traversed
longitudinally by parallel channels in which the volatile liquid flows
as it expands into vapor or gas, thereby forming ice on either surface.
These channeled plates are made of the depth required for the sheets of
ice, and of the length required for the channels. All the thin ice is at
or near the outlet end, and may be allowed to remain until of the proper
thickness. These freezing plates must be so constructed as to expose the
greatest practicable amount of surface with a given number of channels
and weight of metal, and to avoid joints as far as practicable. The said
channels are preferably formed of pipes composed of lead, tin, and
antimony, known in the market as composition pipe. These pipes are
enclosed between plates of light sheet iron, each piece being rolled with
semi-tubular depressions to receive the pipe. The said plates are rivetted
together, thus forming one plate which is made to return upon itself, so
that the whole may be placed in a rectangular tank of convenient
.

page_text: bottom of each of the plates, it is necessary that each of the channels or
pipes should receive the same quantity of liquid. Besides any con-
siderable excess of liquid in any one pipe will be carried into the pump,
and there vaporized and removed by it without deriving any benefit from
its vaporization. The usual means for distribution are found entirely
inadequate to produce the desired result, but the same may be obtained
by the use of a distributor constructed as follows:-It is composed of two
hemispheres of cast iron bolted together by flanges. The lower half
sphere is equally divided into compartments, into the bottom of each of
which is inserted one of the pipes composing the congealer. In the
centre of this is a vertical shaft, the upper part of which is hollow, as is
also the arm extending from it. Into the end of this shaft the liquid is
brought by a pipe.
The constant revolution of this arm deposits an equal quantity of
liquid in each of the compartments or funnels which by its weight sinks
into the pipe connected with it, and thereby secures an exactly equal
division of the liquid to each of the pipes, the number of compartments
being equal to the whole number of pipes in the congealer. This arm
may be moved by the incoming liquid, subject to the high pressure of
the condenser, by constructing it in the form of a reaction or "Barker
wheel, but it is preferable to move it more slowly by the shaft passing
through a stuffing box below, and driving it by means of a pulley.
"
In ice machines heretofore used the flow of liquid to the congealer has
only been governed by the quantity of liquid in the receiver attached to
the condenser; in this improved machine the flow of liquid to the
congealer is governed by the quantity of liquid in the congealer itself.
Any excess of liquid in the pipes will be immediately carried on until it
reaches the water cooler, when it will be vaporized by the higher
temperature of the water surrounding these pipes which will increase the
pressure, and through this increase of pressure the supply is checked by
the mercury guage. This guage consists of an inverted syphon with
enlargements in each leg. The difference of level of these enlarged
portions is made equal to the height of a column of mercury supported
by the average pressure in the congealer, the enlarged portion contains a
float connected with a lever by a rod; the other end of the said lever is
connected with a hollow cylindrical valve, so that an increase of pressure
in the pipes of the congealer acting through the tube upon the mercury
in the cylinder depresses it, and raises the float which closes the valve

page_text: the flow.
Economy of power in working the compressing pump requires the
condenser to be maintained at the lowest temperature practicable. This
object has heretofore been accomplished by means of a running stream
of water of 25 to 30 times the quantity actually made into ice; this large
volume of water is often difficult to obtain, and is in almost all cases
obtained at considerable expence. I substitute for this stream of water
atmospherio air, using water only for the purpose of facilitating the
transfer of heat from the pipes to the air.
The condenser is composed of a series of pipes connected with the
eduction pipe; they descend spirally as they approach the centre, and
then terminate in a hollow cast-iron cylindrical ring which forms a
receiver for the condensed liquid. These pipes and the receiver are
enclosed in a cylindrical casing with openings around the bottom for the
admission of air.
In the centre of the bottom of this casing, which is slightly concave,
is stepped a vertical hollow shaft with four arms carrying a propeller
wheel at the upper end. This shaft is revolved with sufficient velocity
to force the water with which it is charged out of the hollow arms; this.
water descends in the form of spray over the coils of pipe while the
propeller draws the air in through the side openings, and forces it in a.
gentle current out at the contracted top of the casing; the water falling.
on the floor of the condenser runs to the centre and is again drawn into
the shaft, and so continuously circulates, the water serving as a medium
through which the heat evolved by the condensing gas is transferred to
the air through which it is constantly passing as it falls. The said
vertical shaft contains a check valve at its foot, and is charged with
water through the ends of the said arms before putting it in operation.
The ammonia or other liquid is introduced into the machine by
connecting a pipe with the distributor, allowing the gas to drive the air
before it and out through a cock in the receiver. This receiver is filled
about two-thirds full of liquefied gas.
The pump and other machinery being put in operation a cock in
the pipe is opened, allowing the liquid to pass from the receiver to the
distributor, thence to the congealer, where it is converted into vapor by

page_text: '
the heat withdrawn from the water with which the congealer is filled;
thence it passes through the trough to the pump where it is forced into
the condenser through the eduction pipe. In the pipes of the condenser
it is liquefied, and runs down the inclined pipes to the receiver from
which it is again returned to the congealer, and so on continuously;
when the ice on the plates of the congealer is of the required thickness
it is detached by opening a cock and allowing gas from the condenser to
flow into the congealer. These sheets of ice are divided into blocks of
suitable size for handling by flattened sheet iron tubes. These tubes are
closed at the bottom and held in their place before the ice is formed by
connecting them in pairs by a strap, and they are pressed down one on
each side of the freezing plate.
After the ice is formed these flattened
tubes are filled with water of ordinary temperature which detaches them
from the ice, when they may be withdrawn.
After the ice is detached from the freezing plates a bar of iron
inserted into the opening made by the tube easily cracks the remaining
portion of ice, the blocks then float to one end of the tank, and are
hoisted from the same. The new charge of water is pumped in as the
ice is being removed.
It is necessary in order to secure economy in motive power and
produce solid and transparent ice of convenient thickness, that the whole
freezing surface of the congealer should be of sufficient extent to make
the required quantity of ice when the congealation goes on at a rate not
exceeding one-sixteenth of an inch in thickness per hour; and the whole
superficial surface of pipe in the condenser is made equal to one square
foot of surface for every pound of ice or equivalent refrigeration
. produced per hour:
When this apparatus is used for refrigerating rooms, curing meats,
and for other like purposes, the channeled plates in which the volatile
liquid is vaporized are extended longitudinally through the centre of the
room, returning the pipes on themselves to place them all in the same
vertical plane.