IMPROVEMENTS IN WARMING AND VENTILATING, AND IN APPARATUS THEREFOR."
Year: 1879

page_text: LETTERS PATENT to Ludwig Heinrich Hauber, of Munich, in the Kingdom of
Bavaria, for the Invention of "IMPROVEMENTS IN WARMING AND VENTILATING,
AND IN APPARATUS THEREFOR."
Sealed the 7th October 1879, and dated the 15th April 1879.
PROVISIONAL SPECIFICATION left by the said Ludwig Heinrich Hauber at
the Office of the Commissioners of Patents on the 15th April 1879.
LUDWIG HEINRICH HAUBER, of Munich, in the Kingdom of Bavaria.
MENTS IN WARMING AND VENTILATING, AND IN APPARATUS THEREFOR."
" IMPROVE-
The Invention consists in the application of a combination of a number of stoves
forming a central air heating apparatus with a heating chamber, preferably on the
lowest floor of the building to be heated, said stoves being divided into series
which may be controlled separately, while each stove is set upon a base-plate
provided with controllable openings for the admission of air. To ensure a tight fit,
the base-plate as well as the bottom of the stove may be turned, and for filling
each stove is taken out of the heating chamber, filled from the top with small
pieces of coal and coke, and afterwards replaced upon its stand on the base plate.
The cold air enters the heating chamber through a large grid or grids, while the
hot air is conducted through flues or pipes, and well distributed by means of
controllable grids or otherwise before entering the rooms to be heated. In order
to moisten the air, hair, felt, or other suitable material may be placed before the
openings through which the hot air enters, and constantly kept moist by a supply
of water. Each of the stoves may be provided with a conical grate for directing
the air from the centre to the circumference of the stove, and also with vertical ribs
to effect a loose stratification of the coal and coke. The products of combustion
escape from the stoves through tubes or flues into a chimney.

page_text: distribution and conveyance or neat; and tirony, to the numectation of not air.
1. GENERATION OF HEAT.
The point here kept in view is, to attain the most complete combustion with the
least possible surplus of air. As the central hot-air-heating arrangements are
almost exclusively located subterraneously and therefore favoured by a good
chimney draught, that kind of stoves has been preferred which burns the coal from
the top downward, and in this manner the great faults are avoided which attend
most heat generators fed in the ordinary way, because (1) the coals burn free of
smoke, thus causing no impediment to the conductive power of the stove-sides.
(2.) The considerable losses of effect by incomplete combustion and the losses of
heat which are caused by the ashes falling through the slits of the plain grate are
thus avoided. In this system the downward action of the heat serves also to heat
the coals before being burnt.
The accompanying Drawings illustrate an arrangement for central hot-air-
heating calculated for 8 school rooms, each containing 250 cubic meters of air.
In an illuminated heating chamber situated in the deepest part of the house, and
provided with an iron entrance door, 24 stoves are placed, arranged in 4 con-
trollable batteries or sets of 6. Each stove has to contain 8 kilograms of coal and
coke-grit, whose grains vary in size from that of peas to that of hazelnuts, mixed
in equal parts.
The requisite fresh air is conducted to the heating chamber through the air
shaft A (Sheet 1 of the Drawings), the sectional area of which is equal to one
third of the sectional area of all the 8 flues, c¹¹, the area of each of the latter
varying from 0.2-0.25 square meters, for rooms up to 250 cubic-meters of air.
The fresh air passes from the shaft A into the two side channels a, a, and as may
be seen from Sheet II. it is conducted to the heating chamber through the
strainers d, d, placed along the batteries for the purpose of perfect distribution.
The regulation of the air supply can be effected by a trap-door a, which is
suspended by a chain leading over the pulley 6 to the register or indicator o.
The heating stoves consist of the following parts:-
1. The basements B (Sheet II.) are lathe-turned inside, six of which being
screwed down upon a cast iron plate. Into each base is fitted a slide valve b₁,
which can be dislocated 5 millimeters by means of the gearing c. In order to
make the regulation of the air valve practicable from outside, to the lever-end d of
the gearing c a bar is fixed, reaching through the wall and having a screw-end
whose pitch is so chosen, that when the hand which is screwed upon it has moved
from o to X on the dial, the slide-valves will have moved 5 millimeters. If the
hand of the dial be placed upon I, then of all the 6 slide-openings will be open
for the air to enter the mounted stoves. If the hand points at X, all the slits of
the slide-valves are open for the passage of air. If the dial is directed below I a
complete exclusion of air takes place, such as has to be effected when one or
several batteries are to be put out of action.
2. The cylindrical stoves C are provided with ribs c¹ inside which project
1 centimeter; these ribs effect at their respective place a looser stratification of fuel
and with the aid of the conical grating di promote the ascension of the air inside;

page_text: thus the smallest material may be used as fuel if it is free of dust. The stoves are
filled with coals outside of the heating-chamber; some soft and well-dried wood is
placed on the top for lighting the fire. The stoves thus prepared "ready for
lighting" each of them weighing together with its contents 20 kilograms are then
placed upon the lathe turned pedestals B, which they cover hermetically with their
equally turned footings.
At the
3. The short smoke pipes D, six of which being fastened on the cast iron plate
are by means of this plate bolted to the wall of the heating chamber.
point e the neck of the stove joins the above mentioned smoke pipe D.
4. The upright pipes d' made of sheet iron 1 millimeter in thickness conduct the
gases of conibustion into the horizontal collecting pipe e¹, which is also made of
sheet iron 1 millimeter thick, and leads into the chimney f. The openings c¹¹ for
the exit of the warm air can be regulated by slides inside of the heating chamber.
If all of the 8 rooms are not to be heated the respective slides must be closed. In
order to make it possible to ascertain from outside the degree of heat a thermo-
meter g is applied. Though experience shows that by the downward combustion
of the coal hardly any soot is deposited in the conducting pipes, precaution has
been taken in this arrangement to provide by the closing lids being placed
outside of the end-walls for cleansing the pipes at the end of the heating-season
In order to keep the air-currents which are recognized as being obnoxious
remote from inhabited localities, provision has been made to conduct the heated air
into the room by the strainer i, and to lead off the consumed air in a similar
manner through the strainer into the ventilation channel. By means of the
mechanism m, the supply of heated air and the emission of bottom-air may be so
regulated as to meet the requirements.
made:-
A hair-felt 40 / broad and suitably long is placed upon the plate K, which is
made of sheet-zinc, has turned up edges and is fixed in the centre of the hot air-
strainer; this air-felt is suitably moistened by means of a conduit, which by an
experienced hand can be regulated by means of a small tap of easy access. In
this manner the dry air upon entering the room finds an opportunity to quench its
thirst.
In the first moment it might appear as if the attendance of this apparatus
was of increased difficulty in comparison to that of the hot-air-heating with a
single central fire. The contrary however is decidedly the case, and this is already
proved by the fact that in the above explained construction not one half the
quantity of fuel has to be set in motion. An apparatus for 4 batteries of 6 stoves
each can be set in motion within 15 minutes at the longest, as all the manipulations
may be performed with military regularity by an able workman. To avoid the
formation of dust, which cannot be evaded by all other constructions, the stones
are discharged outside the heating chamber, filled again and placed into the hall
of the heating-chamber ready for lighting. During the severe winter months the
apparatus should be continually in activity. According to the temperature a
suitable number of batteries are lighted, and so regulated as to keep up a moderate
heat during the whole night or the desired constant temperature of the room.
The presence of the fireman during the night is of course unnecessary in such
cases. The system excludes all danger of conflagration, the heating chamber

page_text: being solidly built of stone and safely vaulted; moreover, the creation of super-
heated air is systematically excluded. The thermometer g indicates from outside
the heating chamber the degree of the heat inside, which can be precisely increased
or diminished by a quickly acting regulating apparatus.
The essential simplification of the fireman's service, and the fact that leisure time
may be used for feeding the reserve-stoves, render the appointment of special
firemen unnecessary.
The inventor claims as new and peculiar the above described system of
adjustable and controllable central hot-air-heating apparatus, and especially what
follows:-
1. The employment of one or more stoves, constructed as above described.
2. The air strainer by which the cold air is conducted into the heating chamber
in divisions.
3. The air-stainers by which the heated air to be introduced as well as the
vitiated air to be discharged is well distributed.
4. The air moistening apparatus consisting of the air-felt which rests on the
described base.
5. The conical stair-grate screwed into the stove-cylinder for directing the air to
the sides of the cylinder, in connection with the ribs inside of the cylinder to effect
a looser stratification of even the finest fuel.
6. The regulating apparatus which exactly indicates on a dial-plate fixed outside
the changes in the position of the air valves.
7. The regulating apparatus for admitting convenient quantities of air into the
cold air chamber.
In witness whereof I, the said Ludwig Heinrich Hauber, have hereunto set
my hand and seal this Tenth day of October, A.D. 1879.
L. H. HAUBER. (L.s.)