An Improved Method of and Apparatus for Forming Incandescent Bodies for Gas Lighting.
Year: 1898

page_text: Date of Application, 1st June, 1898-Accepted, 16th July, 1898
COMPLETE SPECIFICATION,
An Improved Method of and Apparatus for Forming Incandescent
Bodies for Gas Lighting.
I, WILHELM HEINRICH AUGUSTUS SIEVERTS, of Hamburg-Uhlenhorst, in the
Empire of Germany, Teacher, 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 a method and apparatus for forming incandescent
bodies and more especially for constructing their apex in the form of a solid ring
or shield by using an inwardly directed jet-or blast flame and causing the same
to act upon the incandescent body. Incandescent bodies with a pointed top were
heretofore considered the most suitable as regards shape, owing to this shape
corresponding to that of the flame.
In following this theory, regarding the shape to be imparted to incandescent
bodies it has not however been taken into consideration, that the flame is pointed
only in case it burns freely. As soon, however, as it becomes surrounded by a
mantle it, owing to adhesion, assumes, to a certain degree the shape of such mantle,
provided, that the mantle is sufficiently firm to resist the sucking effect of the
flame. To impart to the incandescent body this rigidity has heretofore been
impossible.
The incandescent body consequently becomes very rapidly contracted and
pointed in an upward direction a defect from which many inconveniences resulted
among which should be especially mentioned the fact, that the chimney is liable
to be easily broken, owing to the jet shaped flame coming in contact with the
chimney at any broken or injured part of the mantle, also the rapid blackening
of the incandescent body and the rapid decrease of the illuminating power.
The object of this improved method is in the first place, to form a firm and
foldless shield or ring at the apex of the incandescent body.
The shaping of the incandescent body is effected by suspending the same, directly
after its having been reduced to ashes, from the top of the burner, by subsequently
placing the burner together with the incandescent body upon a disc, adapted to
rotate around a Bunsen burner, by then igniting the gas traversing the Bunsen-
burner and by finally exposing the burning and rotating incandescent body to the
action of a suitable jet-or black-flame, passing in inward direction. If it should
be desired to impart to the incandescent body a more cylindrical shape, the same
may be slightly inflated at its apex, prior to its being placed on the burner. While
the burner with the incandescent body is rotating around the Bunsen-burner,
illuminating gas is introduced into the said burner at a low pressure. If then the
jet or blast flame is caused to act upon the apex in an inward direction, this apex
is brought into the form of a small shield or ring, which prevents the body from so
yielding as to form a point, and so that the folds produced by the contraction of
any asbestos-thread will disappear.
The same method may be utilized, in order to cause the lower part of each
incandescent mantle to closely join the head of the appertaining burner. Owing
to the inwardly directed and inwardly acting jet-flame passing against the lower

page_text: part of the incandescent mantle, the latter is intimately applied in an inward
direction against the burner-head and becomes softened so that, while exactly
following the outlines of the burner-head, it receives corresponding folds.
This method is illustrated in the accompanying drawing, in which
Figure 1 represents a completely smooth incandescent body, loosely surrounding
the burner.
Figure 2 shows a finished mantle made in accordance with the hereindescribed
process and
Figure 3 shows an apparatus for shaping the incandescent body.
The same consists of a Bunsen-burner a, which is surrounded by a socket d,
carrying the disc b and having its bottom end constructed in the form of a rope-
pulley or disc c. The bearing for this rope pulley or disc c is formed, on the one
hand, by a frame e, fixed below the table top f and, on the other hand, by a plate e¹,
located upon the said frame. The Bunsen-burner is provided with external screw
threads upon its lower end, these screw threads serving to secure the burner in the
frame e; this burner communicates with a gas feed pipe g. The burner h, to
which the incandescent body h¹ is to be applied, is drawn over the Bunsen-
burner a, so that the burner stands upon the disc b and rotates therewith, as soon
as the rope pulley c is set in rotary motion. Instead of this rotation being produced
by the rope pulley it may also be obtained by means of toothed wheel gearings.
The shaping of the incandescent body is effected, during the rotation of the
burning incandescent body around its Bunsen-burner, under the action of an
inwardly directed jet or blast-flame..
Special stress is laid on the fact, that the shaping may be effected-although
in a less perfect manner-by causing the inwardly directed jet or blast flame,
which may also be considered to act as a circular flame, to pass around the burner,
irrespective of whether the latter be burning or not.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1. A method of forming incandescent bodies and more especially of constructing
their apex in the form of a shield or ring, the characteristic feature being, that
an inwardly directed jet or blast-flame, which may also be considered as a circular
flame, is caused to act upon the rotary incandescent body so that the jet-or
blow-flame is passed around the incandescent body.
2. An apparatus for carrying out the process, referred to in the First Claim,
the main feature of the said apparatus being a disc, adapted to rotate about a
Bunsen-burner-tube.
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.