IMPROVEMENTS IN ELECTRIC LAMPS OR REGULATORS
Year: 1879

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
ELECTRIC LAMPS OR REGULATORS." A communication from abroad by
Jean Marie Anatole Gérard-Lescuyer, of Paris, France.
Sealed the 9th March 1880, and dated the 15th September 1879.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 15th September 1879.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
"IMPROVEMENTS IN ELECTRIC LAMPS OR REGULATORS." [A
communication from abroad by Jean Marie Anatole Gérarde-Lescuyer, of Paris,
France.]
Experiments have shown that the much desired division of the electric light can
only be economically and practically attained by means of the arc, the system of
light by incandescence or imperfect contact having been rejected by the inventor
for many reasons, but chiefly on account of the imperfect utilization of the current
and the small results obtained with these two methods.
The imperfect contact system presents superior results in some cases and under
conditions difficult to realise, but it has been found that this was due to the
formation of a small arc accidentally produced by the interposition between the
carbons of a small cinder or vitreous globule which momentarily separates the two
electrodes and permits of the formation of the arc. As however this effect is but
accidental and consequently very irregular in its occurrence, the inventor has
rejected this mode of obtaining light as well as that by incandescence.
In order to form the voltaic arc it is absolutely necessary that the two electrodes
should be separated, and in order to maintain this are in a regular manner it is
necessary that the distance between the electrodes should be kept constant not-
withstanding the consumption of the carbons.
This effect is admirably realised by the large electric light regulators of Serrin,
Gaiffe, Carré, and others, but up to the present time there has been no successful
small regulator constructed. The object of this Invention is to fulfil this want by
the construction of a regulator on the following principle, viz.―

page_text: Given an electrode of small section to maintain it by means of a controlling force
at a constant distance from another carbon of large section which is not consumed
and merely performs the rôle of second electrode.
This principle may be carried out in various ways as I will proceed to describe
with reference to the accompanying Drawings.
The regulator represented in Figure 1 is based on the repulsion which contiguous
portions of a current exert the one upon the other. A is a small cylindrical or
rectangular carbon mounted within a tube B forming the body of the lamp and
guided therein by a sliding piston C having a packing D. The tube B is connected
at the lower part with another tube E attached at one side thereof, the two tubes
commnnicating with each other by the aperture G. A piston F, also packed,
slides in this tube E in which it is made to descend either by its own gravity or
by a spiral spring. When piston F descends it compresses the air confined beneath
it, which passing through orifice G presses against the underside of piston C
and so raises the electrode A. To lower the carbon it is only necessary to draw up
rod H, when a partial vacuum is formed beneath the piston F, and consequently in
tube B, and the atmospheric pressure on piston C causes it to descend and with it
the carbon A. Any suitable liquid may be substituted for compressed air if
desired, the action being the same in both cases.
The carbon A in rising meets with the large bun shaped carbon J which is
mounted on a lever K oscillating on a quadrant L, it being confined thereon by
four small metal straps. A spiral spring M, whose tension is regulated by a
screw N, serves to balance the carbon J. The carbon A is guided at top in a clip
O, the jaw P of which is jointed at Q and has a projecting arm R whose extremity
is engaged in a hook S attached to lever K. This forms the principal part of the
regulator.
The following is the action:-The carbon A is raised by the pressure of the
compressed air until arrested by meeting the carbon J whose weight is thereby
diminished by the upward pressure of the carbon A. By means of screw N the
tension of spring M may be regulated as to so balance the carbon J that the
slightest excess will cause it to oscillate. If now a current passes, the larger carbon
J will be repelled and raised, and the hook S by lifting arm R will cause jaw P to
close and nip the carbon A, which is thereby held fixed. The arc is established
between the two carbons, but as the point of A immediately begins to wear away
the interval between the two carbons increases the resistance opposed to the
current, which, becoming weaker, repels the carbon J less powerfully, whereupon
the carbon J falls slightly by its own gravity, and the hook S no longer lifting
arm R the jaw P is released and opens to allow carbon A to rise, but the arc being
immediately re-established the carbon J is again repelled by the current which has
recovered all its energy and the action recommences as before.
All these movements do not really take place as the larger carbon J has a
constant tendency to descend and keep the clip out of action, while carbon A has a
has a similar tendency to rise as it becomes consumed, and so maintain the arc
always constant and absolutely fixed.
The larger carbon J is not sensibly consumed, and in order still more to preserve
it intact and improve its conductibility I coat it by electro-chemical deposition with
an inoxidizable metal such as platinum or gold. It may also be made wholly of
metal, and gilded or platinized, or a small piece of platinum may be inserted in the
centre of the carbon. With this apparatus a carbon of two millemetres may be
used with the current from a battery of six Bunsen elements or a small Gramme
machine such as used in laboratories. Under these conditions the light produced
will equal eight to ten gas burners, and the wear of the carbon will be eight
centinientres per hour. Carbons of larger diameter may be employed with
greater battery power. In order to introduce the stick of carbon into the lamp,
screw T is loosened, arm L thrown back, and clip O withdrawn, then by pushing
down rod H the piston C is raised so that a fresh carbon can be inserted and
drawn down by the act of raising r d H again.

page_text: In the modified arrangements of lamps represented in the following. Figures, the
same letters of reference are used to indicate the same parts.
Figure 2. In this arrangement the carbon A is fed up by a spiral spring Z,' and
the lamp is regulated by means of a solenoid W which operates a lever X carrying
a screw Y which presses against the carbon A through the guide O.
The larger
carbon J is mounted on a spring K which allows it to yield slightly to the
repulsion of the current, this being necessary for the immediate formation of the
arc, as otherwise incandescence would first take place, and it would be necessary
to wait until the point of the carbon A is sufficiently consumed to establish the
are. It will be readily understood from an inspection of the Drawing that
immediately the current passes the solenoid is excited, attracts its armature, and.
causes screw Y to press against carbon A and hold it until a change in the strength
of the current allows the carbon to rise.
Figure 3. In this arrangement the regulator is inverted, and instead of being
mounted on a base it is suspendend by a hook. The chief feature of this arrange-
ment is that the slide or piston C comprises also an electro magnet W which
alone effects the regulation, the tube B forming the body of the lamp being of iron.
By the action of the current the poles C, C, of the piston electro-magnet C, W, C,
are caused to adhere to the sides of B and hold the carbon A suspended; when the
resistance increases the current diminishes in strength and the attraction between
the poles C, C, and the tube B is proportionately diminished, thereby allowing
carbon A to descend slightly by its own gravity and thus maintain the arc constant.
In this arrangement the larger carbon J is replaced by a small piece of platinum J
brazed to a spring K so that no shadow is cast beneath the lamp, more especially if
the guide O be furnished with a reflector.
Figure 4. This lamp is also suspended by a hook, the feeding of the carbon A
being controlled by an iron barrel V upon which is wound a cord or chain a from
which is hung the slide C. An electro magnet W placed above the barrel V prevents
the cord unwinding to lower the carbon A when the current is passing under
normal conditions; V is a small guide roller to guide the cord down the centre of
the lamp. The other parts of the regulator are the same as those last described.
Figure 5. In this arrangement all the parts of Figure 4 are duplicated as
indicated by the letters, the large carbon J is dispensed with and is replaced by a
second stick carbon A¹ which is consumed equally with the other. The section of
this second carbon A¹ should be twice that of A if the current is continuous, but
they may both be of the same section when an alternate current is used. The
regulation is effected by two barrels V, V¹, whose movements are controlled by
electro magnets W, W¹. The barrels are so arranged as to dispense with the guide
roller v, the cord or chain occupying a nearly central position in the tubes.
Figure 6. This arrangement differs from the foregoing inasmuch as the barrel V
contains a spiral spring having a constant tendency to wind up the cord, and
which passes around two guide rollers vand v¹, the latter roller being mounted on
slide C. The movement of the barrel is controlled by an electro magnet W placed
inside the base of the lamp. A second electro magnet W serves to separate the two
carbons A and J by oscillating the armature lever K. When the current passes the
barrel V is rendered immovable, carbon A remains stationary, and the electro
magnet W' attracting its armature K oscillates lever K and separates the carbons
A, J, to establish the arc.
The above arrangements may be still further modified and other combinations
of the regulators herein described may be made without departing from the
principle of the Invention.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
13th March 1880.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
A com-
Patent Agent.
"IMPROVEMENTS IN ELECTRIC LAMPS OR REGULATORS."
munication from abroad by Jean Marie Anatole Gérard-Lescuyer, of Paris,
France.
Experiments have shown that the much desired division of the electric light can
only be economically and practically attained by means of the arc, the systems of
light by incandescence or imperfect contact being unsuitable for many reasons, but
chiefly on account of the imperfect utilisation of the current and the small results
obtained with these two methods. The imperfect contact system presents superior
results in some cases, and under conditions difficult to realise, but it has been found
that this was due to the formation of a small arc accidently produced by the
interposition between the carbons of a small cinder or vitreous globule which
momentarily separated the two electrodes, and permitted of the formation of the
As however this effect is merely accidental it is consequently very irregular
arc.
in its occurrence.
In order to form the voltaic arc it is absolutely necessary that the two electrodes
should be separated, and in order to maintain this arc in a regular manner it is
necessary that the distance between the electrodes should be kept constant notwith-
standing the consumption of the carbons. This effect is admirably realised by the
large electric light regulators of Serrin, Gaiffe, Carré, and others, but up to the
present time there has been no successful small regulator constructed. The object
of this Invention is to fufil this want by the construction of a regulator on the
following principle, viz.:-Given a carbon of small section to maintain it by means
of a controlling force at a constant distance from another carbon of large section
which is not consumed and merely performs the rôle of second electrode. This
principle may be carried out in various ways, as I will now proceed to describe
with reference to the accompanying Drawings.
.
The regulator represented in Figure is based on the repulsion which contiguous
portions of a current exert the one upon the other. A is a small cylindrical or
rectangular carbon mounted within a tube B forming the body of the lamp, and
guided therein by a sliding piston C having a packing D. The tube B is connected
at the lower part with another tube E attached at one side thereof, the two tubes
communicating with each other by the aperture G. A piston F also packed slides
in this tube E in which it is made to descend either by its own gravity or by a
spiral spring. When piston F descends it compresses the air confined beneath
it, which passing through orifice G presses against the underside of piston C, and
so raises the electrode A. To lower the carbon it is only necessary to draw up rod
H, whereupon a partial vacuum is formed beneath the piston F, and consequently
in tube B, and the atmospheric pressure on piston C causes it to descend, and with
it the carbon A. Any suitable liquid may be substituted for compressed air if
desired, the action being the same in both cases. The carbon A in rising meets
with the large bun-shaped carbon J, which is mounted on a lever K free to oscillate
on a quadrant L, on which it is retained by four small metal straps. A spiral spring
M, whose tension is regulated by a screw N serves to counterbalance the weight of
the carbon J. The carbon A is guided at top in a clip O, the jaw P of which is
jointed at Q, and has a projecting arm R, whose extremity is engaged in a hook S,
formed on lever K. This forms the principal part of the regulator.
The following is the action-The carbon A is raised by pressure of the compressed
air until arrested by meeting the carbon J, whose weight is thereby diminished
by an amount equal to the upward pressure of the carbon A. By means of screw

page_text: N the tension of spring M is regulated to so balance the carbon J that the slighest
excess will cause it to oscillate. If now a current passes the larger carbon J will
be repelled and raised, and the hook S by lifting arm R will cause jaw P to close
and nip the carbon A which is thereby held fixed. The arc is established between
the two carbons, but as the point of A immediately begins to waste away, the
interval between the two carbons increases the resistance opposed to the current
which becoming weaker, repels the carbon J less powerfully, whereupon the carbon
J falls slightly by its own gravity, and the hook S no longer lifting arm R the jaw
P is released, and opens to allow carbon A to rise, but the arc being immediately
reestablised the carbon J is again repelled by the current which has recovered all
its energy, and the action recommences as before.
All these movements do not really take place as the larger carbon J has a constant
tendency to descend and keep the clip out of action, while carbon A has a similar
tendency to rise as fast as it becomes consumed, thereby maintaining the arc always
constant and absolutely fixed. The larger carbon J is not sensibly consumed, and
in order still more to preserve it intact, and improve its conductibility, I coat it
by electro-chemical deposition with an inoxidisable metal, such as platinum or gold.
It may also be made wholly of metal, and gilded or platinised, or a small piece of
platinum may be inserted in the centre of the carbon.
With this apparatus a carbon of 2 millimetres may be used with the current
from a battery of 6 Bunsen elements, or a small Gramme machine such as is used
in laboratories. Under these conditions the light produced will equal 8 to 10 gas
burners, and the consumption of the carbon will be 8 centimetres per hour. Carbons
of larger diameter may be employed with greater battery power. In order to
introduce the stick of carbon into the lamp, screw T is loosened, arm L thrown
back, and clip O withdrawn, then by pushing down rod H the piston C is raised
so that a fresh carbon can be inserted and drawn down by the act of raising rod H
again. The construction and working of this lamp being understood, it will be
unnecessary to describe in detail the modified arrangement of lamps represented
in the following figures in which the same letters of reference are used to indicatė
the same parts.
In Figure 2 the carbon A is fed up by a spiral spring Z, and the lamp is
regulated by means of a solenoid W, which operates a lever X, carrying a screw Y,
that presses against the carbon A through a hole in the guide O. The large
bun-shaped carbon J is mounted on a spring arm K, so that it may yield slightly
to the repellent action of the current, in order to admit of the immediate formation
of the arc, otherwise incandescence would at first take place, and the arc would
not be established until the point of the carbon A had been sufficiently consumed.
It will be readily understood from an inspection of the Drawing that immediately
the current passes the solenoid is excited, attracts its armature, and causes screw Y
to press against carbon A, and hold it until a change in the strength of the current
allows the carbon to rise.
Figure 3.-In this arrangement the regulator is inverted, and instead of being
mounted on a base it is suspended by a hook. The chief feature of this arrangement
is that the slide or piston C comprises also an electro magnet W, which alone effects
the regulation, the tube B forming the body of the lamp being of iron. By the
action of the current the poles C, C, of the piston electro-magnet C, W, C, are caused
to adhere to the sides of B, and hold the carbon A suspended. When the resistance
increases, the current diminishes in strength, and the attraction between the poles
C, C, and the tube B is proportionately diminished, thereby allowing carbon A to
descend slightly by its own gravity, and thus maintain the are constant. For this
arrangement the larger carbon J is replaced by a small piece of platinum J brazed
to a spring K, so that no shadow is cast beneath the lamp, more especially if the
guide O be furnished with a reflector.
In Figure 4 the lamp is also suspended by a hook, the feeding of the carbon A
being controlled by an iron barrel V, upon which is wound a cord or chain a, from
which is hung the slide C. An electro magnet W placed above the barrel V
-

page_text: prevents the cord unwinding to lower the carbon A when the current is passing
under normal conditions. vis a small guide roller to guide the cord down the
centre of the lamp. The other parts of the regulator are the same as those last
described.
In Figure 5 the parts of Figure 4 are duplicated, as indicated by the use of the
same letters with the addition of a digit. The large carbon J is dispensed with, and
is replaced by a second stick carbon A', which is consumed equally with the other.
The sectional area of this second carbon A' should be twice that of A if the
current is continuous, but they may both be of the same section when an alternate
current is used. The regulation is effected by two barrels V, V, whose movements
are controlled by electro-magnets W, W. The barrels are so arranged as to dispense
with the guide roller v, the cord or chain occupying a nearly central position in the
tubes.
The arrangement shewn in Figure 6 differs from the foregoing inasmuch as the
barrel V contains a spiral spring V₁ having a constant tendency to wind up the cord,
and which passes around two guide rollers v and v', the latter roller being mounted
on slide C. The movement of the barrel is controlled by an electro-magnet W
placed inside the base of the lamp. A second electro magnet W¹ serves to separate
the two carbons A and J by oscillating the armature lever K. When the current
passes, the barrel V is rendered immovable, carbon A remains stationary, and the
electro-magnet W₁ attracting its armature oscillates lever K, and separates the
carbons A, J, to establish the arc.
The above arrangements may be still further modified, and other combinations of
the various parts of the regulator herein described may be made without departing
from the principle of the Invention.
Having described the nature of the said Invention and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
hereinbefore recited Letters Patent is,-
1st. A regulator for producing a small are in which a carbon of small section is
maintained by means of a controlling force at a constant distance from another
carbon of large section, which is not consumed and merely performs the role of
second electrode, and which may be made of an incombustible material, all as
herein before set forth.
2nd. In an electric light regulator in which a carbon of small section is main-
tained at a constant distance from a carbon of large section, the combination of the
iron tube B containing a piston C carrying the small carbon A, and fed up by means
of air compressed by a piston F in cylinder E, with the insulated arm L, spring M,
screw N, bent lever K carrying the carbon J, and with the clip O, jaw P, and arm
R, the whole arranged and operating in the manner hereinbefore described, and
shewn in Figure 1 of the Drawings.
3rd. In an electric light regulator in which a carbon of small section is main-
tained at a constant distance from a carbon of large section or other electrode, the
combination of spring Z for feeding up the carbon A with a solenoid W, lever X,
screw Y, support L, and spring K, upon which is mounted the larger carbon J,
all arranged to operate as hereinbefore described and represented in Figure 2 of the
Drawings.
4th. In an electric light regulator in which a small carbon is maintained at a
constant distance from a larger carbon or other electrode, the combination of an
iron tube B with an electro magnet W, two poles C, and small carbon A, descending
by its own gravity towards a platinum or other electrode J carried by spring K,
all as and for the purpose herein before described and represented in Figure 3 of the
Drawings.
5th. In an electric light regulator in which a small carbon is maintained at a
constant distance from a large carbon or other electrode, the combination of a tube
B containing a reel V, guide roller v and cord a, supporting the carbon A and its
slide C with an electro magnet W, as and for the purpose herein before described and
represented in Figure 4 of the Drawings.

page_text: 6th. In an electric light regulator in which two carbons are maintained at a
constant distance from one another, the combination of two tubes B, B¹, two carbons
A, A¹, two slides C, C, with the two reels V, V₁, and cords a, a¹, and two electro
magnets W, W1, the whole arranged and operating as hereinbefore described and
represented in Figure 5 of the Drawings for the purpose specified.
7th. In an electric light regulator in which a carbon of small section is main-
tained at a constant distance from a larger carbon or other electrode, the com-
bination of a tube B, carbon A, and slide C with a reel V, spiral spring V', cord a,
pulleys v, vl, and two electro magnets W, W¹, one acting on the reel and the other
on the upper carbon or electrode J by means of armature K, as herein before
described and represented in Figure 6 of the Drawings for the purpose specified.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Thirteenth day of March, One thousand eight hundred
and eighty.
A. M. CLARK. (L.S.)