Improvements in the Regulating Devices of Horizontal Shunt. Arc Lamps.
Year: 1897

page_text: Date of Application, 26th July, 1897-Accepted, 28th Aug., 1897
COMPLETE SPECIFICATION.
Improvements in the Regulating Devices of Horizontal Shunt. Arc
Lamps.
I, JASPER WETTER, Patent Agent, of 37 and 39 Essex Street, Strand, in the County
of London, do hereby declare the nature of this invention, communicated from
abroad by the Elektrizitäts-Aktiengesellschaft vormals Schuckert & Co., Engineers, of
Nuremberg, Germany, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
1.
This invention, as communicated to me by my foreign correspondents, relates to
improvements in the regulating devices of horizontal shunt are lamps for search
lights which are used especially in the army and navy for night attacks and general
search purposes, as well as for other illuminating purposes.
The regulating device chiefly comprises two electro-magnets, one of which is
excited by the main current forming the arc, while the other lies in a shunt to the
arc and serves to feed the carbons in proportion as they are consumed.
Referring to the drawing, in which the invention is diagramatically illustrated,
Figs. 1 and 2 illustrate the main horse-shoe magnet, both limbs of which are inserted
into the main circuit. Opposite to the poles of the magnet 1 and 2 an oscillating
armature 3 is pivoted at 4 and connected with two helical springs 5 and 6 adjustable
by means of screws 7 and 8 fixed in the wall of the lamp case. A shaft 9 having a
worm 10 is connected with the armature 3 which causes the shaft to follow its
movements.
On a vertical axle 11 is mounted a worm-wheel 12 and a spur wheel 13 which gears
with the racks 14 and 15 supporting the carbon holders 16 and 17 suitably insulated
from the racks. The current is conducted by means of flexible cables directly to the
holders 16 and 17, and to the carbons 18 and 19.
The feeding device, consisting essentially of a horse-shoe electro-magnet, 20 and
accessories is mounted on the base-plate of the lamp. Like the main horse-shoe
magnet 1 and 2, it has an oscillating armature 21 connected with adjustable helical
springs 22 and 23, by which the armature is pressed against the pin 24. The
armature 21 is provided with a connecting spring 25 which is pressed against a
contact pin 26, if the arinature under the influence of the springs 22 and 23 lies on
the pin 24. The contact pin 26 and spring 25 with the magnet coils 20 lie in a shunt
to the carbons. This shunt is broken, if the armature 21 is attracted to a certain degree
by the magnet 20, and again closed, if the armature is removed from the poles
by means of the springs 22 and 23. The armature 21 is connected with a pawl 27,
which slides over a ratchet wheel 28 mounted on the screw shaft, if the armature is
attracted, and which imparts rotary motion to the ratchet wheel 28 and the worm 10,
if the armature is removed from the poles of the magnet 20. The worm wheel 12
transmits these rotations to the toothed wheel 13, whereby a steady approach of the
carbons is obtained.
The regulating device acts as follows.-If the carbons are distant from each other
on the current being switched on, the shunt magnet begins to assert its power,
inasmuch as the armature 21 of the latter, owing to the continual opening and closing

page_text: of the circuit, is caused to perform rapid oscillations, whereby the ratchet-wheel 28,
worm 10 and spur wheel 13 are turned and the carbons brought closer together. If
their points touch each other, the current in the shunt coils 20 is no longer inter-
rupted, while the main magnet 1 and is powerfully excited; it therefore attracts
the arinature 3, and shifts the screw shaft 9, together with the worm 10 and
wheel 13, so that the carbons recede from each other, and the arc is struck.
As the carbons are gradually consumed, the shunt electro magnet 20, by reason of
the increasing resistance in the main circuit, gains sufficient attractive power to
overcome the pull of the springs 22 and 23 and thereby to draw the armature 21 away
from the pin 26, so as to break the shunt circuit. Thereupon the arinature 21 is
again removed from the poles of magnet 20 by the springs 22 and 23, the effect of
this being to turn the ratchet-wheel 28 (by means of the pawl 27) and consequently
worm 10 and spur wheel 13, thus causing the feeding of the carbons. Owing to the
worm-wheel mechanism the approach of the carbons to each other is practically
continuous and steady.
If the carbons are nearly consumed and the racks 14 and 15 have reached their
end positions, the shunt circuit is broken by the spring 30 being lifted off the
contact 31; this is effected by a pin 29 fixed to the end of the rack 15 and adapted
to strike the spring 30, when the rack 15 has reached its end position. The electro-
magnet 20 then ceases to act, and the arc is extinguished after a short time.
The automatic regulating device hereinbefore described may be switched off and
the feeding of the carbons effected by hand, if desired. To this end a hand-wheel 32,
mounted on the extremity of the screw-shaft 9, is turned, and thereby the feeding
device set in motion.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to performed, I declare that what I
claim is :
In horizontal shunt arc lamps, a regulating device chiefly comprising two electro-
magnets placed respectively in the main circuit and in a shunt-circuit, said magnets
having oscillating armatures adapted to actuate the carbon feeling device either
directly or by means of driving gear, and contact-pieces arranged in conjunction with
the armature of the shunt magnet for automatically breaking the shunt circuit,
substantially as and for the purpose described.
T
T. 1007
FAIRFAX & WETTER,
37 and 39, Essex Street, Strand, London, Agents.