Improvements in Electric Arc Lighting.
Year: 1890

page_text: Date of Application, 31st May, 1890
Complete Specification Left, 22nd Oct., 1890-Accepted, 22nd Nov., 1890
PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lighting.
I ALFRED APPS of 433 Strand in the Parish of St. Martin-in-the-Fields in the
County of London Electrical Engineer and Instrument Maker do hereby declare the
nature of said invention to be as follows :-
The object of my invention is to improve the color and intensity of the electric arc
light and to lessen its unsteadiness.
I feed the are flame with hydrocarbon vapour by causing it to pass up through
the lower carbon from a reservoir containing oil or other source of the vapour in or
near the lower end of the carbon. The upper carbon is of the usual sort.
The lower carbon is fitted with a tube or lining containing a very small hole
through which the oil ascends first by capillary action and then becoming vaporized
passes into the arc flame.
By these means the electric are light is much increased in power and improved in
color and steadiness.
Improvements in Electric Arc Lighting.
I, ALFRED APPS, of 433, Strand, in the Parish of St. Martin's-in-the-Fields, in the
County of London, Electrical Engineer and Instrument Maker, 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 :--
The object of my invention is to improve the colour, and increase the intensity
and steadiness of the electric are light, with the least expenditure of electric
energy.
I feed the are with bydro-carbon vapour by causing the vapour to pass up through
the lower carbon (for example), from a suitable reservoir containing the hydro-carbon,
situated at or near the lower end of the carbon. The upper carbon (in this example),
is of the usual kind.
The lower carbon is fitted with a tube or lining containing a very small hole through
which the oil, from the reservoir, first ascends by capillary attraction, and subsequently,
becoming vaporized, passes on into the. are or flame playing between the electrodes.
The résult is a more agreeable colour, and both the steadiness and intensity of the light
are increased, without increasing the electrical energy.
I am aware that hydro-carbons have been conducted through the interior of the
carbon, and that a special method of using hydro-carbon vapours, and preventing the
stoppage of the bore hole through which the vapours pass, consists in-inserting a wick
made of asbestos. I have discovered, however, that a wick is not necessary to keep
the bore hole open, and allow the hydro-carbon vapour to pass. Instead of using a
wick I line the bore hole of the carbon, (or so much as may be burned) with a
suitable refractory insulating material, such as kaolin, lime, plaster of Paris, vitreous
or asbestos paint, japan, stone or earthenware, or even with a tube of asbestos, so as
to form a small capillary tube, which, in the case of ordinary carbons, has a bore hole
of from about one fiftieth to one hundredth of an inch clear diameter for the passage
of the vapour; but this may vary with the size, length, and position of the carbon.
The vapour duct or tube may be straight, convoluted, or helically disposed; and its
transverse section circular or of any other desired shape.

page_text: In making the capillary tube or lining, the lime, plaster or other material used of a
similar nature is preferably introduced within a tubular carbon in a plastic condition,
so that it adheres readily to the interior of the carbon, and a thin wire or other core
inserted therein, and subsequently removed, to preserve the necessary aperture. As
the tube or lining is very thin, and therefore the quantity of mineral matter very small,
it burns or falls away in proportion as the carbon is consumed thus keeping the
hole open for the easy passage of the vapour from the lower part of the carbon, or
from the vessel containing oil, or other source of hydro-carbon vapour.
The lining or
tube serves, not only to convey the vapour to the arc, but also to prevent the deposit
of carbon from the vapour within the passage; which deposit would otherwise form an
obstruction to the flow of the vapour.
In the further description, reference is inade to the accompanying drawings, in
which
Fig. 1 is a longitudinal section of a vertically placed carbon, embodying my
invention, and
Fig. 2 is a cross section.
The carbon A is fitted into a vessel B containing oil up to the level C, which oil
ascends through the small axial perforation k. This passage k is formed in the tube
or lining K of kaolin, plaster of Paris, or other suitable refractory material.
B' is a
brass rod or tube by means of which the vessel B can be fixed to the lamp holder.
The part B may, however, he placed in any other convenient position; and it will
be understood that the carbon may be placed otherwise than vertically if required.
The vessel is provided with an opening, which can be closed by a screw S, and it
serves to admit air to the interior when required. Instead of using a vessel B, the
hydro-carbon oil may be supplied from a separate reservoir placed in a suitable
position, and connected to the inlet end of the carbon by a feeding wick.
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 tubular carbon for electric are lamps containing a lining or tube of refractory
material, substantially as and for the purpose described.
2. A carbon for electric arc lighting having an axial passage provided with a
lining or tube for supplying liquid by capillary attraction, substantially as and.for the
purpose described.
3. The combination of an electric lamp carbon having a small central tube of refractory
material with a source of hydro-carbon supplied at the inlet ond of the said tube;
substantially as and for the purpose described.
4. The combination of a tubular carbon with a plastic refractory insulating material
and a core adapted to form a capillary tube within the said plastic material when dry,
substantially as and for the purpose described.
13
33. 1
CALL 1000
FAIRFAX & WETTER,
433, Strand, London, Agents for the Applicant.