Improvements in Refrigerating Apparatus.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Refrigerating Apparatus.
I, WILLIAM EVERARD EASTMAN, Mechanical Engineer, of 50 State Street,
Boston, Suffolk County, State of Massachusetts, one of the United States of
America, 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, reference being had to the accompanying drawings making
part of this Specification, in which :—
Figure 1 is a vertical longitudinal section taken near the center of a refrigerator
as applied to a car and constructed in accordance with my invention.
Figure 2 a horizontal longitudinal section on the line x, x, of Figure 1.
Figure 3 a vertical transverse section showing an ice receptacle at one end of
the car, looking in the direction of the arrows 15-Figures 1 and 2.
Figure 4 a vertical transverse section through the air space between an ice
receptacle and the freight compartment, looking in the direction of the arrows 16,
Figures 1 and 2.
Figure 5 represents a portion of the outside of the refrigerator, and showing a
thermometer located on the inside of the refrigerator, and seen through a window;
also showing a dial and its index by which the inside temperature may be known.
Figure 6 a horizontal longitudinal section taken a little below the top of the
inside of the car inverted, and having attached to its ceiling an automatic valve-
operating mechanism, and an interposed index mechanism for controlling the
temperature and excess of expansion of the valve-operating device.
Figures 7-8-9-10-11-12 and 13, to be referred to."
To preserve fruit, vegetables, fish, fowl, meat, etc., in a sweet, fresh and market-
able condition, it is necessary to ascertain by observation and experiment, what is
the particular degree of temperature of the surrounding air required for the proper
preservation of each respectively, and then to maintain such temperature without
variation. The object of this invention is to produce a refrigerator either
stationary or movable so constructed that any desired pre-determined degree of
temperature may be maintained for a considerable period of time by automatic or
other means, for instance in a car for conveying fruit a long distance; and, my
invention consists in a refrigerator having peculiarities of construction and certain
thermostatic features applied thereto, to be hereinafter described and claimed.
In the said drawings A represents my improved ice refrigerator applied to a
car for the transportation of fruit, meat, etc., having insulated sides, top and floor;
an ice compartment B being formed at each end, having a thick insulated
partition a interposed between it and the freight compartment b, whereby moisture
is prevented from depositing thereon, and but slight radiation of heat is experienced.
These partitions a do not extend up to the ceiling of the car, thereby leaving a
transverse opening which is divided into two air passages c at each end of the
freight compartment b, each pair of said air passages being controlled by a pair
of valves C which are free to swing on a common anti-corrosive shaft 14, the ends
and middle portions of which rest within anti-corrosive bearings secured to the
opposite sides of the car, and to the insulated partition, these valves being operated
so as to open and close the air passages c by mechanism connected with expansion
and contraction devices to control the air currents and temperature inside the
freight compartment. In the top of each end of the car are preferably located
two openings leading to each ice compartment, said openings being closed by
tightly fitting insulated trap doors Y. Within each compartment B is located an
ice rack or receptacle D formed of galvanized iron slats at its sides, and with a
bottom d of wood having its underside shellaced to prevent condensation and

page_text: dripping of water into cold air passages e thereunder, the upper side d' of the
bottom d being covered with galvanized iron to prevent leakage and corrosion (see
Fig. 13). There are two cold air passages or flues E extending longitudinally
under the insulated floor of the freight compartment leading from the air passages e
under each ice compartment to an opening F cut in the insulated floor; i.e. four
passages or flues E in all, two on each side of the middle sill or sills of the car
bottom. Each ice rack has an air space 42 surrounding its sides, which together
with its open top affords access for the air to come into contact with the ice and
become rapidly cooled, after which, owing to its specific gravity, it descends around
outside of an apron G smaller in area than the bottom of the ice rack to which it
is secured, said apron G extending down nearly to the ice compartment floor to
insure the descent of the cold air to or nearly thereto before it can enter the cold
air conductors I smaller than and located centrally within the apron G. Each
cold air conductor I is of galvanized iron and of greater area than the passage e;
the edge of the open bottom of each conductor surrounding said passage, while
the upper edge of the conductor is turned down to form an outwardly flaring lip f
which prevents the water from the melted ice from swashing over and flowing into
the cold air flues under the floor. Transversely across the center of the bottom
of each ice compartment is a partition v, and leading from the bottom at each side
thereof is a waste pipe w which conveys the melted ice water out of the car (Figs. 1
and 3). The cold air being of greater weight, collects upon the floor of each ice
compartment and is then driven by the air currents under the edge of the apron
and up between it and the cold air conductor I, and over its lip, down the con-
ductor into the passage e and cold air passage or flue E under the floor, up through
the opening F into the freight compartment-(see arrows Figs. 1, 3 and 13), this
being simply a precaution for preventing the air from taking moisture into the
freight compartment. I will now describe an automatic expansion and contraction
mechanism for operating the valves C which control the air passages c, (Figs. 6, 7,
8, 9, 10, 11 and 12).
K is a tube of brass (fourteen feet long, two and seven-eighths inches in
diameter, and one-fourth inch thick) which is hung loosely within clips g, secured
to the ceiling of the freight-compartment, one end of said tube screwing into a
plate, also secured to the ceiling, the other end of the tube having a short
tubular extension screwed thereover, by which construction the tube is free
to expand and lengthen in the direction of the arrow 26 and contract or shorten
in an opposite direction when under the influence of variations of temperature
within the freight-compartment.
Within the stationary end of the brass tube is fitted a hollow cylinder i, free
to slide therein and having a spiral spring located within it, one end of the
spring bearing against the head 18 of a pin or follower 19, which projects through
an opening in the cylinder i and having secured thereto at 20 a lever k, which
is pivoted to a pin 21 passing loosely through it. Inside of this brass tube K is
a cast iron rod L passing through bearings 28, of same outer diameter as the
interior of the tube and free to slide therein, the brass of the tube K being much
more sensitive to changes of temperature than the iron of the rod L. A shoulder 22
on this rod L rests on a seat of the tubular extension and is held thereon
by the expansive force of a spiral spring 23, the outer end of the rod L being
threaded and passing through the tubular extension, and having a regulating nut 25
screwed thereon, the spring 23 surrounding that portion of said rod located in the
extension and the nut being free to slide therein in common with the rod.
The opposite end of this rod is enlarged and screws into the inner end of the
hollow cylinder i and forms a seat 40 for the inner end of the spiral spring j, a
space 41 between the end of the cylinder and plate h being left when the
temperature is at the mean or desired degree for the movement of the cylinder
when the tube and rod contract. From the foregoing it will be readily under-
stood that an increase of temperature will cause the brass tube to expand, and
consequently lengthen in the direction of the arrow 26-i.e. from left to right,

page_text: Fig. 1, it being impossible to lengthen in the opposite direction, owing to its fixed
connection with the stationary plate h, and while lengthening, the distance between
the seat of the extension and the pivot 21 of the lever k will increase and
the spring in the hollow cylinder i will assert itself and cause the cylinder to
slide within the tube K from left to right and oblige the shoulder 22 to follow
the receding seat 7 and press it thereon, the spring 23 also exerting its influence to
draw it on said seat, the expansive capacity of the iron of the rod L being but
very slight, assisting but little in this operation. As the head of the pin 19
is confined within the cylinder i and the pin is secured to the lever k (as before
described) at 20, it follows that when the cylinder moves from left to right, the
lever will also be vibrated in the same direction.
Again when the brass tube is contracting by a decrease of temperature below
the point at which it and the rod L have been adjusted, the distance between
the seat and the pivot 21 of the lever will be reduced and the cylinder i will be
carried from right to left, and close the space 41 which existed between it and
the plate hat the desired mean temperature, the result of which is the spring j
will press the pin 19 from right to left (the plate being cut away to allow of this
movement) and the lever will be vibrated in the same direction, and it is evident
from the foregoing construction that if this automatic device be connected with
the air-valves CC by suitable intermediate mechanism they will be operated
thereby, thus opening and closing the air-passages ce at the tops of the partitions a a
between the freight and ice compartments. The adjustment of the regulating
nut 25 to set the spring 23 to the required tension, the adjustment of the spring j
and the length of the rod L in relation to the length of the tube K and amount
of vibration to be given the lever k, etc., are matters which require much care and
experience, in order that the valve-rods o o will only perform their full stroke or
movement in either direction forward or back, sufficient to insure the maximum
opening or closing of the air passages c by the valves C C and so that the entire
strain exerted thereafter by a continued expansion or contraction of the unequal
expansion pair will be intercepted by the springs and the mechanism and its
connections relieved from injury. I will now describe a mechanism interposed
between said valves and my automatic device for operating them, the object being
to control the expansion pair and adjust the lengths of the connections so accurately
that it will regulate and give the exact movements to the valve-rods when the
temperature inside the freight compartment has arrived at the predetermined
degree desired, the aforesaid springs providing for any additional movement
arising from any excess or further expansion or contraction, whereby a uniform or
nearly uniform degree of temperature is maintained within the freight compart-
ment. To the free or outer end of the lever k is secured one end of a rod m, the
other end being secured at 27 (Fig. 7) to a projection 32 on the outside of a
dial-plate M having numerals represented thereon, and through a cylindrical
aperture in said dial-plate passes a cylindrical brass block or connection n, having
an opening in each end, provided with a screw thread, into which is turned the
inner threaded end of a rod o, the outer end of which is secured by a bifurcated
device p to a pair of discs 29 attached to the center of the shaft 14 of the pair of
valves CC, see Fig. 10. This bifurcated device p is connected with the discs 29
at or near their peripheries, so as to insure the necessary rotation of the shaft to
operate the valves CC.
The central portion of the cylindrical connection n is provided on its outside
with an annular groove 30 into which fits a pin 31 which passes through the dial-
plate M, and while preventing its movement lengthwise independently thereof,
permits it to revolve in common therewith.
N is an index or pointer adjustably connected at one end with one of the rods o
(the left hand one, Fig. 6) and sliding at its opposite end in a dove-tail groove 42
in the dial-plate M. The cylindrical connection n which unites the two rods o is
provided with a milled hand-wheel P which on being turned (through the connec-
tions already described) will cause the connection n and dial to be moved

page_text: at any
simultaneously therewith on the rods o, this dial travelling to the left or right,
according to the direction in which the hand-wheel is turned, and consequently
the lever k will be vibrated to the left or right and the rods o will be adjusted in
length and actuated in the same direction to close the air-passages c
previously-determined temperature indicated by the pointer opposite the figures
representing the degree desired. If a high degree of temperature-say 60°-is
desired to be retained in the freight compartment, the lever k is vibrated to the
right by turning the milled wheel P toward the operator (i.e., revolving the top
toward him) the index or pointer moving opposite the figures indicating 60° on the
dial. If a low degree of temperature-say 40°-is desired, the wheel (i.e. its top)
is turned from the operator and the free end of the lever is vibrated to the left,
while the pointer will move over the dial opposite the figures 40.
Suppose the temperature desired to be maintained within the freight compart-
ment is fifty degrees (50°). When the air therein has arrived at this temperature
(which may be ascertained by a thermometer) the wheel P is turned till the pointer
(moving over the dial) stands opposite the figures "50" thereon, when the lengths
of the valve-rods and connecting mechanism will have been carefully adjusted, so
as to be capable of actuating the valves sufficiently to exactly close the air-
passages cc, simultaneous with which the expansion of the unequal expansion
pair or combination is just adequate to give the necessary vibration to the
lever k to insure precisely this required movement (and no more) of the valve-rods,
and after the said passages are closed, should an increase of temperature occur,
resulting in a still further or excess of expansion, an increased pressure will be
exerted on the rods to open the passages, after which a still further increase of
pressure, resulting from an additional increase of temperature, will be received by
the yielding springs j and 23-that is to say a pressure greater than that produced
by the expansion necessary to exactly close the passages e e-whereby the springs
are made to yield and relieve the connecting mechanism from unnecessary strain
and injury. On the rise of the temperature above 50° inside the freight compart-
ment from lack of ice or for want of sufficient air circulation the air-valves will
open the passages and increase the circulating currents until the temperature
in the freight compartment has again fallen to the desired pre-determined
temperature (50°) indicated by the pointer on the dial, after which the air-valves
will again close the air-passages c c. Should the contraction continue by a still
further reduction of temperature than that sufficient to give the maximum move-
ment to the closing of the valves, the end of the pin 19 will come into contact
with the side of the plate and the spring j will commence to yield. The
springs and 23 perform the office of safety-valves to relieve the parts and
their connections from strain and injury after the rods have properly actuated
the air-valves C C.
Qare sheets of wire netting secured to the ceilings and partition so as to
prevent tampering with the valves C. R is a dial on the outside of the car,
(Fig. 5) and its index secured to the end of the valve shaft 14 projecting
through the end of the car; the object of this outside dial being to enable the
air valves C to be manipulated from the outside, should the automatic mechanism
be out of order or disconnected from the air valves ;-and the temperature inside
the freight compartment may thus be regulated to a limited extent. By having
the air flues E under the floor, with an ice compartment at each end of the car,
and the air passages c closed automatically and promptly by the valves C, I am
readily enabled to obtain and preserve a high degree of temperature in the freight
compartment when so desired, which I believe has not been effected in the
previous history of the art, for the reason that the air currents were always in
full force, because no suitable means were provided for their regulation to and
from the ice. Consequently when I diminish the air circulation where a high
temperature is to be maintained, the supply of ice is more slowly consumed, the
effect of which is a saving of ice proportionate to the degree of temperature
maintained inside the freight compartment, amounting to a saving of from fifty to

page_text: sixty per cent.when a temperature of sixty degrees is maintained inside, win an
outside temperature of eighty or ninety degrees.
The gases generated by the contents of the freight compartment will be carried
through the air passages into the ice chambers, and be there mixed and carried
away with the moisture as it condenses.
Should any ice remain in the ice compartment after the arrival of the car
at the end of the route, it will be preserved for a long time, owing to the
perfect insulation of the floor, walls and partitions, and the capacity of preventing
any circulation of air by closing the air passages c
Another advantage derived from my perfect insulation and arresting the air
circulation is, that I can supply ice to my car before the freight compartment
receives its contents, as the temperature inside the freight compartment will
not be reduced to such an extent as to be objectionable to the packers; whereas
with cars of the old construction, it has been customary first to stow the freight
and supply the ice thereafter, because the low temperature which would be
produced in the freight compartment if the ice were first received would be
detrimental to the health of the packers of the freight. By my construction, the
difference of temperature between the air at the top and that at the bottom
of the freight compartment will usually be scarcely perceptible. and not
exceed from one to two degrees, whereas with refrigerator cars of former
construction, it is common to find a difference of seven to twelve degrees
between said points. A valuable feature of my construction is the insulated
partition and air space above it, without which a high temperature in the freight
compartment could not be preserved when the ice compartments were full of ice.
Instead of an expansion-contraction device consisting of a brass tube and a cast
iron rod as herein described, I may employ other combinations of metal or liquid-
such as copper, zinc, mercury, oil, alcohol, etc., or both metal and liquid, by the
unequal expansion of which the valves may be operated. During the winter
months in a warm climate, such as is experienced in the Southern United States,
when my car is iced and loaded with perishable freight, the ice in melting will
create a circulation inside the car, and the moisture therein (while the air is in
contact with the ice) will be condensed, and after having been eliminated from the
air, the capacity of the latter to conduct heat from the contents of the freight
compartment will be much reduced, whereby the temperature inside the freight
compartment will be held above the freezing point for a much longer time, as the
car advances where the outside temperature is lowering, as in coming North.
When the outside temperature is not higher than 32° above zero, the ice will be
prevented from melting, under which conditions, the air passages will be closed and
the ice will hardly affect the radiation of heat from the contents of the freight
compartment, while the insulated partitions will furnish double protection at the
car ends, and as the circulation will be stopped, they will be better protected from
frost than the sides, whereas in ordinary refrigerator cars, all perishable freight
coming in contact with the ice at the ends of the car (when it is not melted by a
low temperature outside) would be frozen. When a refrigerator is only intended
for preserving corn-fed dressed beef, as said beef requires a given amount of
moisture, I find that the valves C, C, may be dispensed with, in which case the
effective area of the air passage c would be the full size of the opening, as no room
would be occupied by the valve, and in such case the expansion of the air in the
freight compartment will be sufficient to decrease the relative moisture, being that
best adapted to preserve the beef in a sweet condition. The manner in which the
air is dried, or in other words, the amount of moisture it will contain under certain
conditions is approximately as follows. When the air goes from the freight com-
partment to the refrigerating compartment, the temperature will be decreased and
bulk of air reduced, while the amount of moisture given up to the ice will be
proportionate to the decrease in bulk, though still saturated. When the air comes
back to the freight compartment, its temperature will be increased according to
the
way the valves C, C, are set; and its increase in bulk will be proportionate to

page_text: the different temperatures, to maintain which, the automatic valve regulator may
be set.
The ice compartments when iced will always be at a temperature of
33 degrees and if the valves were set to maintain 50 degrees in the freight com-
partment, the air would expand in changing from 33° to 50° sufficiently to diffuse
the moisture throughout a greater volume of air, and in this operation the amount
of moisture per each cubic foot of air, would always be in proportion to the
increase in the bulk of the air. Under just such conditions as I have here stated,
the air in the freight compartment would contain about 3% of the amount contained
in a saturated atmosphere; and it would always be ready to take back the missing
quantity (about 3) from anything containing moisture with which it might come
into contact. If a higher temperature should be maintained in the freight
compartment, the relative amount of moisture would be lessened in proportion to
the increase in the bulk of the air.
A car may be provided with but one refrigerating compartment, but as the width
of a car is limited on account of the gauge of the track, in order to obtain a storage
chamber of sufficient size, the car is necessarily made long, and consequently I
find it convenient to employ two refrigerating compartments, one at each end of the
storage compartment. In stationary refrigerators, however, whose width and form
are not limited or restricted by the width of a track or other circumstance, I find
it advantageous to provide the refrigerator with but one refrigerating chamber, and
locate an insulated partition between it and the storage chamber, with an air
passage between them and a valve therein, said valve being operated by an automatic
expansion and contraction pair or combination.
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
1-The refrigerating compartments B, B, and an interposed freight compartment b,
in combination with insulated partitions a, a, air passages c, c, flues E, E, under the
freight compartment and an opening F in the floor of the latter, as and for the
purpose set forth.
2 The refrigerating compartments B, B, and an interposed freight compartment b,
in combination with insulated partitions a, a, air passages c, c, valves C, C, flues E, E,
under the freight compartment, and an opening F in the floor of the latter, as and
for the purpose described.
3-A freight compartment b and a refrigerating compartment B, located outside
each end thereof, insulated partitions a, air passages c and valves C for controlling
the same, in combination with passages in the bottoms of the refrigerating com-
partments, flues E under the floor of the freight compartment, and openings F in said
floor, all constructed to operate substantially in the manner and for the purpose
specified.
4-A freight compartment b and a refrigerating compartment B, located outside
each end thereof, insulated partitions a, air passages c above them, valves C for
controlling the same, in combination with an apron G extending nearly to the floor
of the refrigerating compartment, passage e in the latter, flues E under the floor of
the freight compartment, and openings F in said floor, as and for the purpose set
forth.
5 The combination of an insulated freight compartment b, two refrigerating
compartments B, B, and insulated partitions at the ends of the former, air
passages c, c, valves C, C, for closing said passages, an ice rack D in each
refrigerating compartment, an air space 42 surrounding the ice rack, aprons G, G,
cold air conductors I, 1, passages e, e, in the bottoms of the refrigerating compart-
ments, flues E, E, under the floor of the freight compartment, and openings F, F,
cut therein, all constructed to operate substantially as specified.
6-A refrigerating compartment B, an ice rack D therein, an apron G under the

page_text: rack, cold air conductors I provided with outwardly projecting flanges f, and located
under said apron-air passages e at the bottom of the refrigerating compartment
and directly under the conductors-flues E extending along the freight compart-
ment floor and openings F therein, leading into the said flues as and for the purpose
described.
7-The combination and arrangement of a refrigerating compartment B, its
aprou G and cold air conductors I, a partition » extending between the conductors
transversely across the floor of the compartment B and a waste pipe w on each side
of the partition v and between it and the contiguous conductor I to allow of the
escape of the water produced from the melting ice as described.
8-In combination-a refrigerating compartment and a freight compartment, an
interposed insulated partition, an air passage therein-a valve located in said passage
and a thermostatic valve-operating mechanism for controlling the circulation of
the air currents between the compartments, substantially as described.
9 In a refrigerator-two refrigerating compartments and an intermediate freight
compartment with interposed insulated partitions, air passages above them and
valves located therein, in combination with a thermostatic valve-operating device
for controlling the air currents within the freight compartment, substantially as
set forth.
10 In combination with a refrigerator car having two refrigerating compart-
ments, and an interposed freight compartment, insulated partitions between them,
air passages above the partitions and valves located in said passages; a thermo-
static valve-operating mechanism, for controlling the circulation of air currents
between the compartments, as shown and described.
11-In combination-a refrigerator having valves located in air passages
extending between the refrigerating and freight compartments-a thermostatic
valve-operating mechanism, a means for controlling the excess of expansion and
contraction of the latter, and an index-setting mechanism which represents the
degree of temperature at which the valves close-and insures the maintenance of
any desired pre-determined temperature, as set forth.
12-The combination of two refrigerating compartments, an interposed freight
compartment, insulated partitions between them, air passages above the partitions,
valves located in the air passages, an unequal expansion pair consisting chiefly of a
brass tube and a cast-iron rod for operating the valves, means for preventing the
excess of expansion and contraction from straining and injuring the parts, and an
adjustable index-setting or thermostatic-regulating mechanism for insuring the
maintenance of a pre-determined degree of temperature within the freight compart-
ment-constructed and operating substantially in the manner described.
13 In combination-a dial R and index r located outside of a refrigerator-
insulated partition a, air passage c, valve C, and valve shaft 14, to which the index r
is secured, for controlling the circulation of the air currents by the manipulation of
an attendant, substantially as specified.
Dated this Fifth day of January 1892.
WILLIAM EVERARD EASTMAN.