Improvements in Cooking Utensils, Boiling Pans, and the like.
Year: 1895

page_text: Date of Application, 9th "ec., 1895-Accepted, 15th Feb., 1896
COMPLETE SPECIFICATION.
Improvements in Cooking Utensils, Boiling Pans, and the like.
I, EMIL HEINRICH CONRAD OEHLMANN, of 131 Linienstrasse, Berlin, in the
German Empire, Engineer, 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 improvements in cooking utensils.
According to my invention I form cooking utensils with a jacket similarly to
cooking utensils heated by steam and 1 introduce into the space between the inner
and outer walls of the same a liquid capable of being evaporated at the ordinary
temperatures employed in cooking such as, for instance, distilled water, the air
being exhausted from the vessel if desired. The object of this arrangement is to
provide means whereby the heat imparted to the outer wall of the utensil or vessel
can be continuously transmitted to the inner wall and so to the contents of the said
vessel without the necessity of constantly renewing the liquid contained in the
space between the walls as is the case with steam cooking vessels which are
continuously supplied with steam or with cooking vessels heated by a water
bath in which fresh water has to be continuously supplied to replace that
evaporated in the course of the cooking process.
The contents of my improved vessel can be easily brought to the boiling point
by means of the liquid contained in the jacket and can be kept hot for a long time
by reducing the flame employed for heating the vessel.
To enable my invention to be fully understood I will describe the same by
reference to the accompanying drawing, in which :-
Figure 1 is a vertical section of a cooking vessel constructed according to my
invention:
Figure 2 is a section on the line of Figure 1:
Figure 3 is a vertical section of a cooking vessel adapted to be heated by a lamp
and having my improvements applied thereto :
Figure 4 is a vertical section of a glass cooking vessel having my improvements
applied thereto.
The vessel A, Figure 1, is provided with an outer wall or jacket a, the space b
formed between the two walls containing a suitable quantity of a liquid such as
distilled water, the said liquid being hermetically or practically hermetically
enclosed in the space which may be emptied of air thus providing a vacuum for
the distilled water or the like.
At the upper part of the vessel A I provide an outlet tube d closed by a safety
plug e adapted to melt at a predetermined temperature. The outlet tube d is
provided with a capf having holes g, g through which the vapour contained in the
space can escape if, by accident, the vessel should be heated when empty.
If, now, the vessel be placed on a fire or over a spirit lamp or be heated by any
other meaus, the liquid in the space b forms a vapour bath which quickly transmits
the heat to the contents of the vessel A without burning the same.
My improved vessel besides being adapted for cooking purposes can also be
advantageously used for keeping liquids or food warm as it can be heated by means
of a flame, such as that from a spirit lamp, which can be easily regulated to impart
the required amount of heat.
In Figure 3 the space between the inner and outer walls of the vessel A
communicates with a space h between the inner and outer walls of a cylinder B.
which is connected to the top m of a lamp.

page_text: h
The space contains the required quantity c of distilled water or the like and is
hermetically or practically hermetically closed, the said distilled water transmitting
the heat of the lamp flame to the contents of the vessel A as hereinbefore
described.
The quantity of distilled water or the like employed is advantageously so small
that no danger can arise from the employment of the lamp cooking vessel which is
also provided with the above described outlet d and fusible plug e, whereby the
vapour in the spaces b and can escape when too high a temperature is attained.
The space is connected to the space 6 by means of tubes n, n so that an outlet i
is left at the top of the cylinder B for the gases of combustion.
b
It is obvious that my improved cooking vessel is also adapted to be heated by a
fat burner, in which case the cylinder B is made of sufficient size to correspond to
that of the burner.
In cases in which the boiling process has to be watched, for instance, for chemical
operations a glass vessel can be advantageously employed. Such a vessel is shewn
in Figure 4.
Pellets of porcelain or the like can be added to the distilled water if desired or
the latter can be replaced by solid bodies capable of absorbing moisture, the said
bodies when heated giving off vapour to form the bath.
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 cooking utensil or vessel having a double wall or jacket hermetically or
practically hermetically enclosing a space to contain a liquid (the space being
exhausted of air if desired) adapted to be vaporized and to transmit the heat
imparted to the outer wall of the vessel to the inner wall and thus to the contents
of the same, the said vessel being provided at its upper part with a safety valve
preferably consisting of a fusible plug, substantially as and for the purpose
described.
2. The combination with a cooking vessel of the kind described in Claim 1 of
a double walled cylinder attached to a spirit or other lamp, the space between the
walls of which is in communication with the space between the walls of the cooking
vessel, the said cylinder jacket being hermetically or practically hermetically closed
and containing the distilled water or other liquid adapted to transmit the heat from
the flame of the lamp to the contents of the vessel, substantially as described and
illustrated in Figure 3 of the drawing.
3. In cooking utensils of the kind described in Claims 1 and 2, the addition of
pellets of porcelain or the like to the liquid employed or the substitution for the
said liquid of solid bodies capable of absorbing moisture as, and for the purpose,
set forth.
11
ليم
1
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.