Improvements in Incubators.
Year: 1890

page_text: Date of Application, 18th Jan., 1890-Accepted, 8th Mar., 1890
Improvements in Incubators.
I, HANS PFAFF of Munich in the Kingdom of Bavaria, Empire of Germany,
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 the apparatus for hatching eggs and has for its purpose
to provide an incubator in which the supply of the necessary warmth is automatically
regulated.
It is known to be essential for a satisfactory development of the brood that the
warm air or moisture should be supplied or replaced in as uniform a manner as
possible. This necessitates great care and uninterrupted supervision and thus
accounts for the fact that the use of artificial hatching is, up to the present time,
more or less restricted to particular establishments for hatching purposes.
The few heating and ventilating regulators hitherto known intended to cope with
the above difficulties could only lead to an imperfect attainment of the end in view,
as, though supplying the apparatus automatically with warmth and moisture they are
themselves subject to almost daily control, renewal of adjusting contrivances etc. to
enable them to continue the regulation for another short period. This is particularly
the case with a regulating float moved by the water contained in the apparatus and
serving to raise or lower by means of a lever mechanism the wick of the lamp.
An apparatus, in which the heat is regulated automatically and incessantly, i.e.
during whole periods of incubation, has not hitherto become known.
The hereinafter described improved incubator with heat regulator represents an
apparatus, any supervision of which can be dispensed with without danger from fire
to the incubator, brood or building. Moreover the improved device has the material
advantage of operating equally well at any temperature of the outer air and admitting
without any deleterious consequences of any considerable change of temperature,
for instance when brought from a heated locality into the free winter air. If the
improved apparatus heated by means of a stove or the like, no further work is
required when the apparatus is once supplied; if the warmth is produced by means
of oil lamps, these need merely be cleaned and provided with oil. The regulator
proper however, which is the soul of the apparatus, does not require any further
control when once adjusted.
Referring to the accompanying drawing
Fig. 1 is a top view of the improved apparatus with the two covers removed.
Fig. 2 a top view with the upper cover removed.
Fig. 3 a front elevation of the same, the door being open.
Fig. 4 is a vertical section of the complete apparatus.
The improved incubator consists of two receptacles a and b introduced into each
other and is closed at the top by means of two covers c and d.
The arrangement of the apparatus, though likewise novel, is not intended to be
claimed, but may be explained for the purpose of making the whole properly
understood, while the regulator will be subsequently explained.
The bottom of the cylinder a is covered with a layer of sand, on which is placed
the lamp, which may be of any suitable construction and made to consume any kind
of oil. If stove heat or gas is employed in lieu of the lamp, this does not in the
least alter the effect. The holes e serve to admit the necessary air for combustion.
The cylinder is closed at the top with a lid f, which, together with the chimney tube g
and pipe g' appertains to the regulator. The hatching space proper, enclosed by the
receptacle b, consists of the outer casing and a double receptacle hi, secured within
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page_text: receptacle, while the inner space of i serves to receive the eggs. The receptacle h,
with is closed by a cover c with glass pane, while the outer receptacle 6 extending
slightly more upward, that is to say the whole apparatus is closed by the cover d.
The warmth is produced by heating the space intervening between the cylinder
bottom and the water and egg receptacle hi and therefore transmitting the heat to
the latter and to the recéptacle b. The ventilation is effected through holes k in the
receptacle 6 through which holes fresh air is admitted, which mixes with the warm
air enclosed between band h and enters in a preliminarily warmed state through
holes into the hatching receptacle i which is uniformly warmed by the water; the
utilized air leaves the apparatus through the tubes leading from the hatching space i
through h and 6 to the outside of the apparatus. The moisture is supplied to the
eggs by the product of evaporation from the water passing through the holes m
provided in the connection of h and i, which is covered with a likewise perforated
ring m¹, into the hatching space. The supply and escape of air are automatically
regulated. The degree of moisture is ascertained by means of a hygrometer
introduced into the egg space and subsequently regulated by displacing the ring m',
whereby the apertures m are more or less opened or closed, that is to say by
determining the quantity of evaporation to be supplied.
The temperature regulator consists of the following arrangements:
A flap n preferably of mica-slate rests on a central opening provided in the lid f
of the cylinder a. Said flap is movably secured in the support o by means of the
lever n¹ and carries at the other extremity of the latter a clamping screw p and a
set screw 9. These two screws serve as counter poise and, by corresponding
adjustment of the set screw, the flap can always be overbalanced, that is to say, held
open. Within the egg receptacle (hatching space) however a bimetallic spring ris
provided in the centre, which is enclosed in a box, indicated by dotted lines in Fig. 1.
To the free extremity of said spring a pin s is secured which extends downwardly
through a water-tight opening in hi and is introduced into the clamping screw p.
When the apparatus is in action and the thermometer t projecting outwardly
from the hatching space i indicates a temperature of about 32° Réaumur, which
must neither be exceeded nor fail by more than one degree, the regulator is adjusted
to this degree of temperature, that is to say the pin s, when closing the flap n is
screwed fast in the clamp p. Now the regulator comes in operation i.e. the bimetallic
spring expands, thereby drawing up the pin and pressing down the flap.
Consequently the supply of heat is shut off, which latter is now compelled to pass
through the eduction tube 9 9' and flow out without producing any effect on the
apparatus.
g
When the water in hi and consequently the air in the hatching space gradually
cools down, the spring re-contracts, the pin s is drawn downward by the weight of
clamp p and screw q and the flap reopens, thereby allowing the heat to pass once
more upward through f. As may be seen from the above the tube conduit forms
an essential constituent of the whole arrangement, as without the same the heat could
not be independently regulated but would remain in cylinder a and continue to
produce its effect in an indirect way. According to practical experiments the play
of the improved regulator is extremely precise and maintains the apparatus--within
a fluctuation of but ½ degree i.e. approaching as near as possible that of nature-
always at a uniform temperature.
The regulator and the construction of the apparatus guard it from any abrupt
change of temperature, while, after having been out of work for weeks, therefore
cooled down, the mere adjusting of the lamp suffices to make it operative at once
without any alteration of the regulator.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim is:
An incubator having an absolutely self-acting thermal regulator consisting of a
flap n provided in the lid f of the cylinder a and movably secured by means of
lever n¹, a bimetallic spring within the hatching space i, said two constituents

page_text: being connected with each other by means of pins and clamp p, and the heat
eduction tube g g¹ provided below the flap n, substantially as and for the purpose set
forth.
11.
" T
1000
HANS PFAFF.
By Huelser & Co.,
142, Fleet Street, London, Attorneys.