Improvements in Supporting Rods for Incandescence Bodies.
Year: 1897

page_text: COMPLETE SPECIFICATION.
-Improvements in Supporting Rods for Incandescence Bodies.
T, OSCAR MOIR, Solicitor, of Rudolstadt, Thuringia, in the Empire of Germany,
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 fol-
lowing statement:-
This invention has for its object the production of supporting rods from
materials which in their physical and other properties avoid the disadvantages of
the known supporting rods used for similar purposes.
- The usual metal supporting rods, in consequence of their high rate of heat
conductivity, absorb a considerable quantity of heat, which would otherwise be
used in the illuminating body, and thus raise the gas consumption; furthermore
certain metals oxidise very rapidly. The metal rods have therefore a compara-
tively short life and are, especially when of platinum, very expensive to produce.
To avoid these difficulties the metals have been replaced by Magnesium and
porcelain earths but these even have a considerable power of conducting heat and
they become incandescent and very soft when the incandescent light is burning.
In this condition they bend very easily and become crooked, whilst, when cold,
they are easily broken.
The rods prepared according to this invention become harder. in a very high
temperature whilst their absorption of heat is far less than that of the ordinary
rods.
In consequence of the lower conductivity of heat the burner itself is heated to a
considerably less extent.
The supporting rods are composed of clay slate in the natural state, a slate com-
position, or a mixture of fine clay, steatite, and graphite.
The production of the carrying rod from clay-slate is effected by working the
clay slate out of the mineral by means of any suitable apparatuses. The prepared
rod is hardened by being heated to incandescence, or the hardening can take place
when in use. As all kinds of clay-slates are not suitable for the manufacture of
supporting rods, on account of various mineral constituents, and the cost of work-
ing up the same is comparatively high, ground slate alone or in combination with
other earths or similar suitable substances may be made into a paste and the sup-
porting rods produced by forcing the same into suitable moulds, whereby the
manufacture is simplified and cheapened. The supporting rods thus manufactured
are hardened before use.
Where the slate for the preparation of supporting rods is difficult to obtain or
of unsuitable character, a composition of the following materials may be used:
Good white fire resisting clay in preponderating quantity is mixed with a small
quantity of steatite or an equivalent quantity of Magnesium silicates or graphite,
n the form of a powder, and ground wet to a fine pulp. From this are formed the
ods required which are spread out to dry in the air on a small table or in a warm
oom. They are then baked hard in fire resisting capsules at a temperature of
bout 1400° C. A temperature of 600° C. is sufficient to give them rigidity the

page_text: excess of temperature, and that arising in their actual use, serving only to make
them harder.
The
In practice it is found that a mixture of 100 parts should consist of 96 parts clay
3 parts steatite and one part graphite. The proportion of clay and steatite may
vary within certain limits, but the clay must always be present in excess.
prepared rods, in spite of the addition of the greyish black graphite have always a
greyish white colour, as graphite burns white.
Other bar like bodies which may be used in a similar way to supporting rods,
for incandescence bodies, may be produced from the described substances.
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. Supporting rods or the like for incandescence bodies consisting of clay slate
worked in its natural condition or moulded from a slate composition pressed and
hardened by incandescence.
2. Supporting rods or the like for incandescence bodies composed of a mixture
prepared in the manner described of clay, steatite and graphite and from which
the rods are formed as herein before described, pressed, and hardened in a tempera-
ture up to 1400° C.
3. The improvements in supporting rods for incandescence bodies substantially
as described.
D
1ell
T
1007