Improvements in Gas Heating and Cooking Apparatus.
Year: 1895

page_text: Date of Application, 9th Oct., 1895-Accepted, 9th Nov., 1895
COMPLETE SPECIFICATION.
Improvements in Gas Heating and Cooking Apparatus.
I, FRANZ LÖNHOLDT, of 83, Bockenheimer Landstrasse, Frankfort-on-Main,
Germany, Architect, 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 gas stoves used for cooking and for heating and has for
its object to ensure the utilization of the heat in a more advantageous manner than
heretofore by so directing the course of the escaping products of combustion (the
latter being effected in a manner similar to that described in the Specification of
Letters Patent previously granted to me No. 22,565 of 1894) as to cause them to
give up a larger proportion than usual of their heat to the air by means of which
the process of combustion is maintained.
In both the cooking and heating forms of my improved stove, means are
provided whereby at starting, part of the products of combustion may be allowed
to pass directly into the chimney for the purpose of heating the latter and thus
inducing a sufficient draught. The cooking stove is further so arranged that the
flames do not impinge directly upon either the oven or other spaces or the vessels
to be heated, which receive heat partly through the reflection or radiation of the
heat rays from a reflector and partly from contact with the products of combustion
flowing in a stream extending across the entire width of the hot plate and thence
passing around the spaces to be heated.
In the accompanying drawings illustrating the preferred arrangement of my
improved stoves.
Figure 1 is a front elevation of the form of stove used for heating;
Figure 2 is a sectional plan on the line 2-2 of Figure 4.
Figures 3 and 4 are sectional elevations on the lines 3-3 and 4-4 respectively
of Figure 2.
Figure 5 is a front elevation of the form of stove used for cooking; and Figures 6
and 7 are respectively a sectional elevation and plan of the same on the lines 6-6
and 7-7.
In the chimney-like heating stove illustrated in Figures 1 to 4, the combustion
chamber is situated in front of the lower portion of a series of vertical flues the
upper portions of which project forward over the combustion chamber as shown.
Combustion is effected in the manner described in the Specification before referred
to, the heated products dividing above the fire-bridge towards both sides and
thence passing into the lowest portion of the two outer flues. Between these
vertical flues are arranged a number of similar flues separated by intermediate
spaces for the passage of the air to be heated, said intermediate spaces being
open towards the bottom, the top, and in a forward direction above the combustion
chamber.
The flames issuing from jets in the gas pipe a and burning in the combustion
chamber A receive the air for combustion through the passage B which extends
behind the heated reflector A' and into which the air enters through the grating b.
The flames burn around the front edge of the fire-bridge a', and the products of
combustion pass into the space H which extends horizontally over the entire width
of the stove. When the stove is first lighted, a slide or damper G, controlling an
opening in the centre of the cover plate g of the space II, is drawn out, thus
allowing part of the products of combustion to escape into the upper portion of
the flue C, (which rests with its front upper portion directly upon the plate g)
whence they pass directly into the chimney D. As soon as the latter has become
sufficiently heated to ensure a steady draught, the slide G may be closed. On

page_text: bath sides of the space. I are openings a which lead back into the flues ("', (", the
hot gases first passing through these openings and thence being deflected by the
inclined guide plate of into the lower purtions of these two flues" C', 0%. The hot
gases ascend behind this guide plate and through connecting pipes or necks c',
and into the intern diate flues (2 and C down which they pass, finally entering
the central flue (3, which is preferably of somewhat greater width, and from an
opening in the top of which the products of combustion, now entirely deprived of
heat. escape into the chimney D. "The tubular connections or necks,, between
the flues (³, (7, C, are preferably arranged in zig-zag under relatively to each
other so as to prevent the converging events of heated gases from impinging
directly against one another. A cover F serves to allow of access to the
central flue.
The whole series of fines (1, to 0% are enclosed in a casing E whose front, both
above and below the coalustion chamber A, tant if required whose top also) is
formed by an open grating. In consequence of this arrangement there is a ready
communication of heat from the products of combustion to the air entering from
below between and around the flues and rising rapidly in the vertical passages.
The air in passing out through the front grating is also exposed to radiation from
the highly heated plate which also radiates its heat directly into the apartment
to be warmed.
=
In the cooking stove illustrated in Figures 5, 6, and 7, the flames are similarly
produced from jets along a gas pipe extending throughout the entire width of
the combustion chamber and beneath n fire-bridge a'. In this pipe a, at a point
about one-third of its length from the front, is lined a cock which may be operated
by means of a hand-rody so as to shut off the rear portion of the pipe when the
production of heat is required only at the front of the stove. A burner, with
a pointed jet-nozzle, serves for igniting. A reflector A, extending obliquely
beneath the burner pipe a from front to back of the combustion chamber, forms,
together with the stove plates 1, n, k, an air heating chamber N into which air
enters through an opening N', in the front of the stove, this air after becoming
heated passing around the lower edge of the reflector plate A', to the point of
combustion. It is to be observed that all the air required for combustion is
thoroughly heated before reaching the flame by the plates 7, n, k, and reflector A',
and that a flame of very high temperature is produced flowing in a substantially
horizontal direction over the reflector A', the heat of the flame being intensified
in consequence of the hot products of combustion becoming accumulated in the
angle formed by the upper end of the reflector A, and the upper part of the wall.
The heat radiated from the reflector impinges upon the bottom of the stove
plate Mand thus the heat given off from the burning gases is effectually utilized.
The products of combustion pass along beneath the entire surface of the top plate
of the stove, around the hot water heating coil Q, and over the top plate of the
oven K, and afterwards descend by the end flue P into the botton flue R of the
even, thus making the entire circuit of the oven, and finally pass around the plate
warmer S and into the space L', wherein the water boiler 1. is suspended, and
thence into the chimney T. When the chimney opens direct from the boiler
space 1', it is advantageous to allow the heating gases to enter this space only at
the side opposite to the chimney opening and not along the entire width of the
stove, so as to compel the gases to remain in contact with the sides of the boiler
as long as possible before escaping into the chimney. The wall is perforated
above the reflector, the openings this formed being controlled by means of a sliding
damper which can be opened by means of a handle a from the front of the store
so as to permit the heating gases to pass directly into the chimney for the purpose
of creating the requisite draught on starting the stove.
With this construction of stove the cooking utensils are not heated by the
direct netion of the gas-jets which might possibly damage thein, but they are
heated partly by means of a uniform current of hot products of combustion and
partly by the heat reflected by the reflector. Furthermore as the products of

page_text: combustion are constantly employed in heating the oven, the boiler, and the plate
warmer S, they have no opportunity of escaping into the chimney until after
having parted with all their heat. The fact of there being only one heating place,
instead of a separate burner under each cooking opening in the hot plate, has the
effect of considerably reducing the amount of attention required by the stove.
is essential that the entire stove be kept closed, in order that the results described
may be produced.
It
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what [
claim is :-
:-
1. A closed gas stove adapted to be used for heating purposes, comprising a
series of vertical flues for the escape of the products of combustion arranged side
by side with intervening spaces adapted to serve for the passage and warming of
the air supply, and a gas burning apparatus contained in an enclosed chamber
arranged in front of the lower parts of the vertical flues so as to discharge the
products of combustion into the lower portion of such flucs, substantially as
described.
2. Providing a gas stove of the kind referred to in Claim 1, with a space situated
above the fire-bridge and communicating at both sides (by means of openings at
the rear) with the outermost flues, such space being furnished towards its upper
part with means of direct communication with the chimney through an opening
capable of being closed at will, substantially as described.
3. In a gas stove of the kind referred to in the foregoing claims, the particular
arrangement by which the intermediate air spaces between the flues above the
combustion chamber are left open towards the front, and in which the flues
themselves project in front over the combustion chamber, as described.
4. In a gas store of the kind referred to in Claim 1, the particular arrangement
of the flues and their connections whereby the escaping products of combustion
are compelled to travel in an upward and downward direction alternately, as
described.
5. A gas cooking stove in which a row or series of gas jets or flames extend
transversely of the stove beneath a fire-bridge and are fed, from the rear only,
with air preferably previously heated whilst the products of combustion flow along
beneath the hot plate, substantially as described.
6. In a gas cooking stove the arrangement of gas jets issuing in a substantially
horizontal direction and of a horizontal or inclined reflector situated beneath thic
flames and adapted to deflect or radiate the heat rays upwards on to the hot plate,
substantially as described.
7. In a gas cooking stove of the kind referred to in Claim 4, the arrangement
whereby the products of combustion are caused to pass downwards from beneath
the hot plate and around the oven, thence beneath or around the air inlet chamber
and into a boiler flue before escaping into the chimney, substantially as described.
8. In a gas cooking stove of the kind referred to in Claim 6, the provision of
means whereby the air required for combustion is caused to pass between the
reflector and the fire flue or path of the products of combustion before reaching
the flame, substantially as described.
9. In a gas cooking stove of the kind referred to in Claim 7, the provision of an
opening (capable of being closed at will) in that wall of the combustion chamber
which is nearest to the opening into the chimney, substantially as and for the
purpose specified.
10. In a gas cooking store of the kind referred to in Claim 5, the arrangement
of a gas cock for shutting off a part of the burners, substantially as described.
Dated this 9th day of October 1895.
A. M. & WM. CLARK,
53, C'hancery Lane, London, Chartered Patent Agents.