An Improved Differential Arc Lamp.
Year: 1892

page_text: Date of Application, 27th May, 1892-Accepted, 27th Aug., 1892
COMPLETE SPECIFICATION.
An Improved Differential Arc Lamp.
I, RICHARD HOLSTEN of 51 Berlinerstrasse, Leipsic, in the German Empire,
Gentleman 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 electric arc lamps and its object is to regulate the
carbons automatically by the use of a special device so that at all times a constant
arc is produced.
In order that this invention may be the better understood I now proceed to
describe the same reference being had to the accompanying drawings and to the
letters and figures marked thereon.
Figure 1 shows a complete front elevation of the lamp.
Figure 2 is a side elevation of the lamp.
Figure 3 is a plan.
Figure 4 shows a carbon holder.
H is an electro-magnet arranged in the main circuit, while the electro magnet N
and the feed magnet A. are arranged in shunt circuits n n' (Figure 3).
Of these two shunt circuits one passes from the binding screw P, (which is
insulated, and attached to one end of the main circuit) around the magnet N, to
the magnet A, and thence to the lamp frame; the other shunt circuit n' passes only
around the magnet N, and thence to the lamp frame. The main circuit by the
insulated binding screw P passes by h, around the electro magnet H and thence
by h to the vertical insulated column connected flexibly to the upper carbon.
The lower carbon is connected flexibly to the lamp frame, and thence by the
binding screw Q, to the return of the main circuit.
The carbon holders a and b are held respectively and moved by each end of a
chain which goes round once over the chain drum e with which is rigidly con-
nected a cog wheel f1 revolving on the same axle. A rocking bar E is also
pivoted on the same axle and carries a pulley at each end over which the chain d
passes.
The guiding tubes or pieces B and D of the carbon holders a and b, are con-
nected by chains d over the ends of the rocking bar E which is attracted at one
end by the magnet N of the shunt circuit when the current enters the lamp.
This takes place when the carbons F are standing apart and the main circuit is
broken in which case the feed magnet A comes also into action by the shunt circuit
so that the upper carbon F is moved downwards and the lower carbon upwards by
the action of the vibrating contact piece and pawl lever J turning the ratchet
wheel S and thus by the gearing the drum e raising one part of the chain
attached to the lower carbon support b and lowering the other part of the chain
and the upper carbon support a. When the carbons touch, the larger proportion
of the main current passes through the bobbin H Figure 3. The lower end of
the rocking. bar E is then released by the electro magnet N in the shunt circuit,
and the electro magnet H of the main circuit attracts the other end of the
rocking lever E drawing the carbons apart by the reverse turning of the drum e
and thus the arc is formed.
The feed magnet A remains out of action until the carbons have been burnt too
far and the resistance to the main circuit is thus greatly increased.
In conse-
quence a considerable current passes through the shunt circuit n n¹ so that one
end of the rocking lever E is again attracted by the electro magnet N of the
shunt circuit, and the feed magnet A is set in operation and reduces the distance

page_text: of the carbons from one another until the excessive resistance in the main circuit is
removed.
If the carbons touch each other before the current enters one end of the rocking
lever E is immediately attracted by the electro magnet H of the main circuit and
the arc is made instantaneously.
The distances between the carbons are regulated in this manner.
The electro feed magnet A acts upon the spring hinged contact piece J which
makes and breaks contact with the bent contact piece i, the vibrating piece J is
regulated by the spring k, the lever m and the screw l. The vibrating piece J.has.
at its upper end a pawl engaging into the ratchet wheel S. The rocking | lever E,
which is set by means of springs g and g¹ can be regulated so that the lamp will
"set" to electro motive force or to quantity of current.
By means of the guiding pieces B and D attached to the movable carbon
supports
connected by chains to the rocking lever E, a very effective, secure and even
equalisation of the current is effected. Further, the whole arrangement of the
lamp is such that disengagement of the lamp to renew carbons is obviated. Further,
easy connection of the circuit wires is rendered possible, and the mechanism is not
affected by heavy blows.
By means of the peculiar sensibility of the adjustment of the carbons, differences
in the current are equalized. Further, a certain commencement of the arc is
obtained, and an even feed of the carbon is effected.
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
1st. An electrical differential arc lamp having two movable guiding tubes B
and D for the carbon holders a b connected by chains or flexible material to a drum
upon the axis of a rocking lever E attracted at one end by an electro magnet
wound in the main circuit and at the other end by an electro magnet wound in a
shunt circuit.
2nd. An electrical differential arc lamp having the arrangement of a feed magnet
in the shunt circuit and a vibrating contact piece thereon Jadjusted by the lever m
spring and screw 1, and carrying a pawl at its upper end, in combination with a
bent contact picce i to effect a certain positive feed of the carbons towards one
another, when the main current is diverted in considerable quantity through the
shunt circuit.
Date of Ma. 1900
FELL & WILDING,
1, Queen Victoria Street, London, E.C., Agents for the Applicant.