Improvements in Vacuum Ice Making Machines.
Year: 1889

page_text: Date of Application, 12th Aug., 1889-Accepted, 2nd Nov., 1889
COMPLETE SPECIFICATION.
Improvements in Vacuum Ice Making Machines.
I, GEORG EMIL OSCAR LANGE, of No. 35, Schönhauser Allee, in the City of Berlin,
Germany, Engineer, do hereby declare the nature of my said 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 vacuum ice making machines, that is, to that class of ice
making machines in which a vacuum is employed for producing cold and reducing the
temperature of the water until it is frozen.
In the accompanying drawings,
Figure 1 is an elevation of my improved machine, partly in section.
Figure 2 is a vertical section of the air pump on an enlarged scale.
The cast iron receptacle a, Figure 1, is filled three parts full with concentrated
suphuric acid.
A tube d runs from the lid of cover b of the receptacle a and is con
nected at its free end with a vessel in which the ice is to be formed. In small
machines of the present construction, which are specially constructed for domestic
use, the vessel can be an ordinary water bottle as shown in Figure 1.
A hollow tube g is fixed to the cover b, stands in connection with the vessel a and
is connected to a suction pipe i leading to the air pump h. The air pump, which will
be hereinafter fully described, can be operated by hand or by means of a crank disc
and a fly wheel m with hand crank on the shaft k. If machine power is available a
strap drum can be arranged on the shaft k and be driven by a driving strap from the
shafting so as to operate the air pump. A stirring device consisting of the shaft o and
the wings n is arranged in the cast iron receptacle a, the object of which is, that when
the ice machine is in operation the sulphuric acid in the receptacle will be thoroughly
stirred.
The shaft o carries at its upper end, which passes air tight through the cover b of
the receptacle a, a lever p with handle to enable the shaft o to be rotated in both
directions and thus produce a more energetic stirring of the acid.
The operation of the machine is as follows:-
As soon as the air pump is put in action the same will suck out the air located
above the sulphuric acid in the receptacle a, and produce a partial vacuum. The air
in the vessel above the water to be frozen will, in consequence of this rarefaction,
flow through the tube d into the receptacle a. If the pumping operation is continued
the vacuum in the vesself and the cast iron receptacle or reservoir will become higher
so that at first a slow but gradually increasing evaporation of the water in the vessel /
ensues in consequence of the same being continuously rendered more free from atmos-
pheric pressure. The water so evaporated passes through the tube d into the
reservoir a and is not pumped out with the air still remaining in the said receptacle
but comes in contact with the sulphuric acid and is fully absorbed by the same.
absorbent power of the sulphuric acid is considerably increased by intermittently
subjecting the same to the energetic action of the stirring device without which the
upper surface of the sulphuric acid would soon become so saturated with water
that the absorption of the vapour arising from the water vessel would soon cease.
The
The requisite warmth for producing vapour is abstracted from the water in the
vesself so that the temperature of the same is successively decreased until all or the
greater part of the water in the vessel f is converted into ice.
If an ordinarywater bottle is used the ice in the same can be broken upand removed
from the same by energetically shaking the same.
My improved vacuum pump is constructed as follows:
The casing of the pump consists of three cylinders a³, a a³ arranged vertically one
above the other and containing three pistons b¹, b², 6³ rigidly attached to a common

page_text: The
piston rod, the piston being provided with suitable packing. The pistons are
provided with several borings which are closed by appropriate flap valves d'.
heads or upper parts f³, f³ of the cylinders a² a³ are also provided with borings f
which are also closed by appropriate valves g. The piston rod kruns through a
central boring of the heads of the cylinders f, f³ of, and is provided with, a suitable
stuffing box. The upper end of the piston rod is screwed into a cylinder or trunk h
open at its upper end which makes a reciprocal vertical movement in the upper
cylinder a and is provided with a suitable stuffing box. To the interior of the
trunk or cylinder is attached a connecting rod it by means of the bolt 1, the
upper end of the connecting rod being connected by the crank pin to the disc
so that when the shaft k is rotated a reciprocating movement is communicated to
the piston rod and the pistons. A tube pleads from the upper end of the
cylinder a and is provided at its lower end with an oil trap s with outlet pipe 6, said
tube serving to lead off the air from the air pump. The lower end of the pump casing
communicates with the suction space m¹ with suction valve n¹ and suction canal,
which latter is in connection with the suction pipe i. The tube or pipe i and the
piece of tubing connects the pump with the empty space in the sulphuric acid
receptacle or reservoir.
In order to prevent any acid from passing into the pump when the receptacle
or reservoir a is washed out the suction pipe is bent in syphon form and of suffi
cient height to attain the desired result. An oil receptacle q' filled with oil and
provided with a suitable regulating cock is fixed to the base of the machine and
from which a tube ¹ leads to the suction space m of the pump in order to fill
the same with oil. The tube is enlarged at u in order to catch and retain any
oil that might otherwise penetrate to the receptacle a if the valve m² should be
broken or become untight." In order to avoid all noxious space when the pistons
are at their extreme lower part of the down stroke, not only the suction space m
but all the borings in the pistons and the spaces between the piston and
cylinder head f2, the piston 62 and the cylinder head f³ are entirely filled with
oil. So much oil also stands above the two pistons 62, 63 that when the same
reach the highest point of the upstroke the space between the pistons and the
cylinder heads f³, and also the borings are perfectly filled with oil.
The oil above the upper piston 6 serves to hold the same tight as is also the
case with the other pistons.
The operation of the air pump is as follows :—
If the three pistons are moved upwards from the lower limit of the stroke an
empty space will be produced beneath the same, whereas the air contained in the
space above the pistons 62 63 will be compressed so as to leave the two valves g¹ g'
and fill the space beneath the pistons 61, 62. In like manner the air in the suction
service c¹ and will open the valve and flow through the oil in the space m
into the space beneath the piston 63 until all three pistons have finished their
upstroke. As soon as the pistons commence their downstroke the air beneath the
same will open the valves flow through the oil above the piston and fill the
space above the said piston so that the said air at the next stroke may be pressed
into the next higher lying cylinder until it is eventually driven into the outer air
through the pipe p. In this manner the rarefaction of the air in the cylinders
increases in inverted direction, that is, the air in the lower cylinder is more
rarefied than in the upper cylinders and in this manner and by continued pumping
a perfect vacuum will be attained in the receptacle or reservoir a and also in the
refrigerating vessel f. The small quantity of oil ejected by the pump at each
stroke of the pistons is caught in the oil traps and flows through the tube t back
into the oil vessel q' from whence it again circulates through the pump.
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-A vacuum ice making machine, consisting of the receptacle or reservoir for

page_text: sulphuric acid, the pump and the refrigerating vessel, which said parts are so con-
nected with each other by appropriate pipes or tubes that the vapour sucked out
of the refrigerating vessel must pass the sulphuric acid receptacle or reservoir and
be absorbed by the said sulphuric acid in the same so that a cooling and freezing
of the water in the refrigerating vessel is attained, substantially as and for tho
purpose set forth in the foregoing specification, and as shown in the accompanying
drawings.
2:-In vacuum ice making machines, the pump B consisting of three valve-
pistons arranged one above the other on the piston rod and à pump casing consisting
of three superposed cylinders, the said parts being so arranged that an increasing
rarefaction of the air beneath the three valve pistons is produced in combination
with an oil circulating arrangement whereby a continuous packing or covering of the
three valve pistons with a layer of oil is attained by means of the oil vessel with
borings such as cf substantially as described.
3: The construction of my improved ice making machine, substantially as and
for the purpose set forth and shown.
100
1990
W. P. THOMPSON & BOULT,
Agents.