Improvements in Electric Arc Lamps.
Year: 1888

page_text: "ate of Application, 9th Jan., 1888
Complete Specification Left, 18th Sept., 1888
Complete Specification Accepted, 14th Dec., 1888
[Communicated from abroad by THE FIRM OF SIEMENS & HALSKE, of 94, Mark-
grafen Strasse, Berlin, in the Empire of Germany, Electrical Engineers.]
Improvements in Electric Arc Lamps.
I, CHARLES DENTON ABEL of No. 28 Southampton Buildings, Chancery Lane in
the County of Middlesex Consulting Engineer and Patent Agent do hereby declare
the nature of this invention to be as follows:-
According to the present invention the framing containing the upper carbon of an
are lamp is suspended from a metal band chain or cord wound round the circumference
of a barrel mounted on a horizontal axis and containing a coiled spring so arranged
that the weight of the carbon and its frame tends to rotate the barrel in opposition to
the spring. The barrel or the axis thereof carries a toothed wheel which is
connected by a train of wheels to an escapement which may be either a pendulum or
fly, whereby the rotation of the barrel and consequently the descent of the carbon is
made to take place at a slow regulated speed.
:
The barrel with its wheelwork and escapement is mounted on an inclined frame
pivotted at its lower end at a point near the axis of the barrel to standards on the
lamp framing the upper end of the frame carries the armature of an electro magnet
arranged in a shunt circuit of the lamp so that when the electro inagnet attracts the
armature it tends to turn the frame downwards on its pivots, and thus to lower the
barrel carried by it, whereby also the upper carbon will be lowered. The frame is
held at its upper end by a spring the tension of which is regulated to withstand this
action with irore or less force and which when no current is passing through the
electro magnet holds the frame in such a raised position that the movement of the
escapement is arrested by a stop. When the frame is in this position and the upper
carbon is thereby raised to such a distance from the lower carbon that no arc is
formed, the strong current passing through the shunt circuit will cause the electro
magnet to attract the frame thus also lowering the carbon, until the escapement is
freed from the stop, whereupon the carbon and its frame will be free to descend in

page_text: As
turning the barrel until the upper carbon comes in contact with the lower one.
the current will now pass through the carbons, that passing through the shunt and
electro magnet will be weakened to such an extent as to allow the spring to raise the
frame again so as to arrest the escapement and raise the upper carbon sufficiently to
form the arc, a position of equilibrium being established as soon as by the increasing
resistance of the are, a sufficient current passes through the shunt and electro-magnet
to cause this to hold the action of the spring in equilibrium. When by the burning
away of the carbon, the resistance of the arc increases beyond this point the attraction
of the electro magnet overcomes the force of the spring and the frame, barrel and
carbon are again lowered until the normal resistance of the are is re-established,
and so on.
For introducing fresh carbons, the upper carbon frame is raised by hand, where-
upon the spiral spring in the barrel is enabled, in uncoiling to turn the barrel so as
to wind up the suspension band or chain again, the train of wheels being so arranged
that this can be done more or less rapidly without actuating the escapement.
The varying weight of the upper carbon in burning away is compensated for by
means of a small helical spring connected to a cord that is led over a roller on the
frame above the axis of the barrel and is wound round the axis of the latter, so as to
be coiled upon the same as the barrel is rotated by the descending carbon. Thus the
spring being strained to the least extent when the carbon has been freshly introduced,
its tension, and consequentlyi ts downward pull upon the frame will increase in
proportion as the weight of the carbon decreases.
In place of the spiral spring in the barrel may be used a cord wound upon the
barrel in the opposite direction to that of the band from which the carbon is suspended,
the free end of which cord is attached to a weight or spring.
Or in place of the barrel may be used a pulley with a deep V groove over which
passes a cord or chain one end of which is connected to the upper carbon frame,
while the other end is connected either io the lower carbon frame, if this be moveable,
or to a balance weight.
Dated this Oth lave of Tonum. 1000

page_text: Improvements in Electric Arc Lamps.
I CHARLES DENTON ABEL of No. 25 Southampton Buildings Chancery Lane in the
County of Middlesex Consulting Engineer and Patent Agent, 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 :-
According to the present invention the framing containing the upper carbon of an
arc lamp is suspended from a metal band, chain or cord wound round the circum-
ference of a barrel mounted on a horizontal axis and containing a coiled spring so
arranged that the weight of the carbon and its frame tends to rotate the barrel in
opposition to the spring. The barrel on the axis thereof carries a toothed wheel
which is connected by a train of wheels to an escapement which may be either a
pendulum or fly, whereby the rotation of the barrel and consequently the descent of
the carbon is made to take place at a slow regulated speed.
The barrel with its wheelwork and escapement is mounted on an inclined frame
pivotted at its lower end at a point near the axis of the barrel to standards on the
lamp framing the upper end of the frame carries the armature of an electro magnet
arranged in a shunt circuit of the lamp so that when the electro magnet attracts the
armature it tends to turn the frame downwards on its pivots and thus to lower the
barrel carried by it, whereby also the upper carbon will be lowered. The frame is
held at its upper end by a spring the tension of which is regulated to withstand this
action with more or less force and which, when no current is passing through the electro
magnet, holds the frame in such a raised position that the movement of the escape-
ment is arrested by a stop. When the frame is in this position and the upper carbon
is thereby raised to such a distance from the lower carbon that no arc is formed, the
strong current passing through the shunt circuit will cause the electro magnet to
attract the frame, thus also lowering the carbon, until the escapement is freed from
the stop whereupon the carbon and its frame will be free to descend in turning the
barrel until the upper carbon comes in contact with the lower one. As the current
will now pass through the carbons, that passing through the shunt and electro-magnet
will be weakened to such an extent as to allow the spring to raise the frame again so
as to arrest the escapement and raise the upper carbon sufficiently to form the arc; a
position of equilibrium being established as soon as by the increasing resistance of
the arc, a sufficient current passes through the shunt and electro magnet to cause this
to hold the action of the spring in equilibrium. When by the burning away of the
carbon, the resistance of the arc increases beyond this point the attraction of the
electro magnet overcomes the force of the spring and the frame barrel and carbon
are again lowered until the normal resistance of the arc is reestablished and so on.
For introducing fresh carbons, the upper carbon frame is raised by hand whereupon
the spiral spring in the barrel is enabled, in uncoiling to turn the barrel. so as to wind
up the suspension band or chain again, the train of wheels being so arranged that
this can be done more or less rapidly without actuating the escapement.
The varying weight of the upper carbon in burning away is compensated for by
means of a small helical spring connected to a cord that is led over a roller on the

page_text: frame above the axis of the barrel and is wound round the axis of the latter so as to
be coiled upon the same as the barrel is rotated by the descending carbon. Thus the
spring being strained to the least extent when the carbon has been freshly introduced,
its tension and consequently its downward pull upon the frame will increase in
proportion as the weight of the carbon decreases.
In place of the spiral spring in the barrel may be used a cord wound upon the
barrel in the opposite direction to that of the band from which the carbon is suspended
the free end of which cord is attached to a weight or spring.
Or in place of the barrel may be used a pulley, with a deep V groove over which
passes a cord or chain one end of which is connected to the upper carbon frame, while
the other end is connected either to the lower carbon frame, if this be moveable or to
a balance weight.
C
15
on
Fig. 1 of the accompanying drawings is a side view and Fig. 2 is a plan of
regulating apparatus according to this invention for an electric arc lamp. The
frame which carries the upper carbon is suspended by a conducting metal band
cord or chain m from a barrel d containing a volute spring which in uncoiling tends
to raise the carbon. The barrel d is mounted in a frame which is pivotted at
standards s projecting up from the base a. On the same pivotted frame is carried
multiplying gearing by which the rotation of the barrel d is communicated to an
escapement wheel and pendulum that controls the movement of the barrel. At the
end of the frame which is held in an inclined position by a spring f¹ (adjustable by
a setting screw y acting on lever z. n) is an armature' facing the pole pieces of an
electro magnet e.
The coils of this magnet are in a shunt circuit to that of the lamp,
so that, the greater the resistance of the lamp, the more powerfully is the armature h
attracted in opposition to the spring f'. When it is so attracted withdrawing the
escapement lever w from a fixed stop g. the carbon frame c is lowered partly by the
descent of the axis of the barrel and partly by the rotation of the barrel.
When the resistance of the lamp is thus lessened, the electro magnet e becomes
correspondingly weakened, and the frame is raised again by the spring, raising
the carbon frame c and engaging the escapement with the stop g. Thus the lowering
of the upper carbon is governed according as the resistance of the lamp is greater or
less. In order to compensate for the lessening of the weight of the carbon as it is
consumed, a spring f strains a cord which passes over a pulley on the frame » and
becomes wound on the axis y of the barrel as the barrel revolves lowering the carbon
so as to exert more and more downwards strain on the frame the more the carbon
is consumed.
Having now particularly described the nature of this invention and in what
manner the same is to be performed I declare that what I claim is.
1. In regulating mechanism for an electric are lamp suspending the upper carbon
from a spring. barrel or weighted pulley which has its rotation governed by an
escapement or its equivalent, and which is mounted on a frame having its position
relatively to a fixed stop governed by an electro magnet in a shunt to the lamp
circuit, so that when the resistance of the lamp is excessive, the barrel is released
from the stop and the carbon descends, substantially as herein described.
2. In lamp regulating mechanism such as is referred to in the preceeding claim,
the arrangement of the spring 2 in combination with the pulley.b on the frame »
and with the barrel axis y. substantially as and for the purpose set forth.
Dated this 17th day of September 1888.
ABEL & IMRAY,
Agents for the Applicant.