Improved Manufacture of Mantles for Incandescence Gas Burners, and Apparatus therefor.
Year: 1895

page_text: Date of Application, 12th Jan., 1895-Accepted, 23rd Feb.,
1895
COMPLETE SPECIFICATION.
Improved Manufacture of Mantles for Incandescence Gas Burners,
and Apparatus therefor.
I, MAX ARENDT, of 57 Behrenstrasse, Berlin, Germany, Banker, 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:
In the manufacture of refractory mantles for incandescence gas burners as
heretofore carried out, a mantle formed of suitable fibrous network is first saturated
with a metallic salt solution, and is then subjected to heat in the open air for
simultaneously converting the metallic salt into an oxide and burning away the
In this
fibrous fabric, so as to leave a corresponding network of the said oxide.
process of manufacture, the mantles are liable to deformation which can only be
remedied with great trouble and with considerable loss, unless special means are
adopted for avoiding the deformation.
According to my present invention I avoid this defect, by first subjecting the
fibrous mantle before its saturation with the salt solution, to a carbonising process
at a moderate heat within a closed vessel in which consequently the carbonisation is
effected in an atmosphere of the gases resulting from the carbonising process and
while the mantle is situated upon a correspondingly shaped mould whereby on the
one hand the mantle is made to retain the exact form required after carbonisation,
while on the other hand it retains approximately the same degree of flexibility as
the original fabric with sufficient strength to allow of its manipulation its porosity
being at the same time increased by the fact that it opens out or becomes spongy
while being carbonised at a low heat so that it is better adapted to absorb the
metallic salt with which it is subsequently saturated.
By this means, when the carbonised mantle, after having been saturated with the
salt solution, is subjected to the action of the oxidising flame, no such distortion
occurs as takes place when the uncarbonised saturated fibrous mantle is subjected
directly to the oxidising flame in the usual manner and the completed incandescence
mantle is consequently maintained of the same form that was imparted to it by the
mould and is also of increased strength.
The said carbonisation of the fibrous mantle can be carried out in various ways;
by way of example I will describe an arrangement for this purpose shewn on the
accompanying drawing, which shews a vertical section of the apparatus arranged
for producing an incandescence mantle of a bell or conoidal shape.
Over the burner a of a Bunsen lamp A is arranged a hollow body c of the shape
which it is required to impart to the mantle d, and which is carried by supports /
from the burner stem. The hollow body c can be made of metal or any other heat
resisting material; over it is fitted a hood e, also of heat resisting material, and of
such a size as to leave a certain space between it and the body c, the said hood
being made to rest with its lower edge in an annular trough f, formed on the lower
end of the hollow body so that by introducing pulverulent refractory material
such as powdered fireclay or graphite into the trough, the joint can be made
airtight.
g
The supports carrying the body c, f, are fixed to a sleeve a secured adjustably
to the burner stem by means of a screw h.
For effecting the carbonization of a mantle, the hood e having been removed, the
11 C

page_text: to the mantle the exact shape required; the hood is then replaced and fitted
airtight as described, after which the lamp is lit so as by the moderate heat
produced such as about 500° C. to carbonise the mantle d, such carbonisation taking
place in an atmosphere composed mainly of the gases evolved by the carbonisation
of the fibrous material. By thus effecting the carbonisation at a moderate
temperature under the influence of the said gases, with exclusion of the atmosphere,
the fibrous material is made to swell or open out to a spongy consistency, thus
obtaining a carbonised material which is almost as flexible as the uncarbonised
fibre. The mantle thus obtained, after removal from the mould is then saturated
with the metal salt solution and after drying it is subjected to the action of an
oxidising flame in the usual manner, thereby producing a network mantle of a
cohering oxide body the form of which is the same as that of the original carbonised
mantle, because during such oxidation no appreciable distortion can occur, while
the sudden evolution of gases such as occurs with the direct burning of the
saturated fibrous mantle, and which prejudicially affects the cohesion of the
particles of the oxide body, is obviated by the preliminary carbonisation of
the mantle.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. A manufacture of mantles for incandescence gas burners, wherein a mantle of
fibrous network is first carbonised under exclusion of the atmosphere while placed
upon a mould, whereby its flexibility is retained while its absorbent properties
are increased, such carbonised mantle being then saturated with a metallic salt
solution and, after drying subjected to an oxydising flame, substantially as
described.
2. A mantle adapted for use in the manufacture of incandescence mantles such
as are referred to in the first claim, consisting of a mantle of fibrous network
carbonised by subjecting it to moderate heat under exclusion of the atmosphere,
substantially as described.
3. Apparatus for producing carbonised mantles such as are referred to in the
first and second claims, consisting of the combination of a hollow body such as c
serving as a mould for the incandescence mantle, a hood such as e fitted over the
hollow body c, and a gas burner or other heating device for heating the interior of
the hollow body, substantially as described.
Dated this 12th day of January 1895.
ABEL & IMRAY,
Agents for the Applicant.