IMPROVEMENTS IN ELECTRIC LAMPS
Year: 1882

page_text: LETTERS PATENT to Henry Harris Lake of the firm of Haseltine, Lake,
& Co, Patent Agents, Southampton Buildings, London for an Invention of
"IMPROVEMENTS IN ELECTRIC LAMPS" Communicated to him from abroad by
Richard Robert Moffatt of Brooklyn, New York, United States of America.
PROVISIONAL SPECIFICATION left by the said Henry Harris Lake at the
Office of the Commissioners of Patents on the 12th June 1882
HENRY HARRIS LAKE, of the firm of Haseltine Lake & Co, Patent Agents,
Southampton Buildings, London, "IMPROVEMENTS IN ELECTRIC LAMPS." [A com-
munication to him from abroad by Richard Robert Moffatt of Brooklyn, New York,
United States of America.]
This invention relates to electric lamps of the kind which are known as
arc-lamps.
One object of the said invention is to provide a novel, simple and effective means
for controlling the feeding of the movable carbon.
To this end the said invention partly consists in an electric lamp comprising
the combination of an electro-magnet in the main circuit, an armature therefor
having connected to it means for gripping, raising, and holding a rod whereby the
movable carbon is supported, a toothed rack on the said rod, one or more gear
wheels in engagement with the said rack, a ratchet or other driving wheel, an
electro-magnet in a derived circuit, and an armature therefor having connected to
it a pawl or dog, which, on the raising of this armature will act on such driving
wheel to impart motion thereto and thereby effect the feeding of the said carbon,
but at other times will leave said wheel free.
Preferably I do not connect the means for gripping, raising and holding the rod
supporting the movable carbon directly to the armature of the electro-magnet in
the main circuit, but to a lever with which such armature is connected. I also
combine with the means for gripping, raising, and holding the aforesaid rod, a device
whereby such means will be caused to release the rod when the electro-maguet
becomes demagnetized

page_text: Instead of connecting the aforesaid pawl or dog directly to the armature of the
electro-magnet in the derived circuit, I preferably connect it with a lever to which
the armature is secured. Preferably I combine with this armature a spring, and
means for adjusting it to vary the resistance which it offers to the operation
of the armature so as to provide for regulating the length and resistance of the arc.
Another object of this invention is to provide a simple and effective means
whereby any one of a number of lamps arranged in the same circuit will be cut
out whenever an abnormal resistance or an interruption occurs, as for instance by
the breaking of a carbon in the circuit within the lamp so that the other lamps
will not be extinguished. I also desire to produce a means for the purpose named
which shall also re-establish the arc in the lamp whenever the carbons come
together again. To these ends the said Invention further consists in the com-
bination in an electric-lamp of an electro-magnet in the main circuit, a cut-out
circuit and a device controlled by the said electro-magnet and adapted to close
the cut-out circuit whenever an abnormal resistance or an interruption occurs in
the main circuit, and to break the cut-out circuit whenever the main circuit is
re-established by the carbons coming together. The device mentioned may
advantageously consist of a lever having the armature of the electro-magnet
connected to it and the electro-magnet may be one which also controls the feeding
of the movable carbon.
The said invention further consists in the combination in an electric lamp, of an
electro-magnet in the main circuit, a cut-out circuit, a device controlled by the
electro-magnet and adapted, whenever the main circuit is established by the carbons
coming together, to first break the cut-out circuit, and then effect the separation of
the carbons, whereby the cut-out circuit is prevented from interfering with the
electro-magnet in separating the carbons.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Harris Lake in the Great Seal Patent Office on the
12th December 1882.
"
HENRY HARRIS LAKE, of the firm of Haseltine, Lake, and Co. Patent Agents,
Southampton Buildings, London, "IMPROVEMENTS IN ELECTRIC-LAMPS," A com-
munication to me from abroad by Richard Robert Moffatt, of Brooklyn, New York,
United States of America,
This invention relates to that class of electric lamps known as arc lamps
One object of the said invention is to provide novel, simple, and effective means
for controlling the feeding of the movable carbon.
To this end one part of the said invention consists in the combination, in an
electric lamp, of an electro-magnet in the main circuit, an armature therefor
having connected to it mechanism for gripping, raising and holding a rod whereby
the movable carbon is supported, a toothed rack on the said rod, one or more gear-
wheels in engagement with the said rack, a ratchet or other driving wheel, an
electro-magnet in a derived circuit, and an armature therefor having connected to
it a pawl or dog which, on the raising of this armature, will act on such driving
wheel to impart motion thereto and thereby effect the feeding of the said carbon,
but at other times will leave the said wheel free.
Preferably I do not connect the mechanism for gripping, raising, and holding the
rod supporting the movable carbon, directly to the armature of the electro-magnet
in the main circuit, but to a lever with which such armature is connected. I also
combine with the said mechanism for gripping, raising and holding the aforesaid
rod, a device whereby such mechanism will be caused to release the rod when the
electro-magnet becomes demagnetized
Instead of connecting the aforesaid pawl or dog directly to the armature of the
electro-magnet in the derived circuit, I preferably connect it with a lever to which
the armature is secured. I also combine with this armature a spring, and means
for adjusting it to vary the resistance which it offers to the operation of the
armature, so as to provide for regulating the length and resistance of the arc.
Another object of the said Invention is to provide simple and effective means
whereby any one of a number of lamps arranged in the same circuit will be cut out,
whenever an abnormal resistance or an interruption occurs, (as for instance by the
breaking of a carbon within a lamp in the circuit) so that the other lamps will
not be extinguished. I also produce a means for the purpose named which shall
re-establish the arc in the lamp whenever the carbons come together again.
To these ends another part of the said Invention consists in the combination in
an electric lamp of an electro-magnet in the main circuit, a cut out circuit, and a
device controlled by the said electro-magnet and adapted to close the cut-out
circuit whenever an abnormal resistance or an interruption occurs in the main
circuit, and to break the cut-out circuit whenever the main circuit is re-established
by the carbons coming together The device mentioned may advantageously consist
of a lever having the armature of the electro-magnet connected to it. Preferably
I include within this cut-out a resistance which is equal, or nearly equal, to that of
the arc.
Another part of the said Invention consists in the combination in an electric
lamp, of an electro-magnet in the main circuit, a cut-out circuit, a device controlled
by the electro-magnet and adapted whenever the main circuit is established by the
carbons coming together, to first break the cut-out circuit and then effect the
separation of the carbons, whereby the cut-out circuit is prevented from interfering
with the electro-magnet in separating the carbons

page_text: Another part of the said invention consists in the combination in an electric
lamp, of a main circuit, an electro magnet therein, an armature therefor, a movable
carbon-holder provided with a rack, a shunt or derived circuit, an electro-magnet
in this circuit, an armature for the electro-magnet last named, a device held in
position by the armature of the electro-magnet in the main circuit so that it can
lock the movable carbon holder in position, a ratchet or escapement wheel, a device,
operated, by the armature of the electro magnet in the shunt or derived circuit and
controlling the rotation of the ratchet or escapement wheel, and mechanism operated
by the armature of the electro-magnet in the shunt or derived circuit whereby, after
this armature has moved a distance sufficient to shift the device which controls the
rotation of the ratchet or escapement wheel, the shunt or derived circuit will be
broken so that the armature will be permitted to return to its normal position to
close the said shunt or derived circuit again.
In the accompanying Drawing
Figure 1 is a sectional elevation of an electric lamp embodying this Invention
Figure 2 is a sectional elevation of the same on the line x x Figure 1 looking to
the left
Figure 3 is a sectional elevation on the line x, x Figure 1 looking to the right
Figure 4 is a horizontal section of the said lamp
Figure 5 is a side view of a lever which has attached to it the armature of the
electro-magnet in the main circuit, and carries the device for gripping raising and
holding the rod supporting, the movable carbon.
Figure 6 is a perspective view of another lever contained in the lamp
Figure 7 illustrates in sectional elevation a modification of this invention; and
Figure 8 is a horizontal section of the same.
Like letters indicate corresponding parts in the several figures.
Referring to Figures 1. 2, 3. 4. 5 and 6, A indicates the frame of the lamp which is
made of metal, and B a metal box or case containing mechanism whereby the upper
movable carbon is adjusted to form the arc, and its feed controlled for the purpose
of regulating the length of the arc. This box or case is connected to the frame but
insulated from it. In the drawing the carbons are not shown but the lower carbon
is fastened to the frame A in any suitable manner, and the upper carbon is fastened
to a metal rod or holder C which is supported in bearings in the box or case B, and
is free to move vertically therein. The holder Cis provided with a toothed rack D¹,
and with this rack engages a pinion D2 mounted on a shaft supported in a frame D³
which is affixed to the box or case B, On the same shaft with the pinion D² is a
gear wheel D' which derives motion from a gear wheel D³ on a shaft Do A gear
wheel D7 on this shaft De derives motion from a pinion Ds on a shaft D° on which
is also arranged a ratchet wheel D10 which serves to impart motion to it. When
motion is imparted to the said ratchet wheel the pinion D', moves the upper carbon
holder C downwards, but owing to the relative sizes of the gear wheels referred to,
a less motion is imparted to the rod than is given to the ratchet-wheel, but with
a correspondingly greater power. The pawl Ĕ is pivoted to a standard erected
on one of two levers F which are at one end pivoted to the box B and at the
other end carry the armature F¹ for an electro-magnet F. The movement of the
armature F¹ towards the electro-magnet F is resisted by a spring F, which at one
end bears against the armature and at the other against a screw F³, whereby its
tension may be varied. This electro-magnet F is in a derived circuit which will
presently be described. A spring a impels the pawl towards the ratchet wheel.
G indicates an electro-magnet in the main circuit Its armature G₁ is mounted
on two levers G' which are arranged between the levers F, and similarly pivoted
to the box B. These levers Q² are united at their free ends, and the upper carbon
rod C passes between them-F is a catch consisting of a bell-crank-lever pivoted
at the end of one arm to a rod b, which extends between the levers F³, so that its
angular portion can act on the said carbon-supporting rod The other arm is
actuated by a spring c so that the angular portion will be forced against the said
carbon-supporting rod. This catch serves to maintain the carbon-supporting rod

page_text: in any position to which it may be adjusted but does not prevent it from being
forced downwardly by the pawl E, in order to regulate the arc. When the electro-
magnet G attracts its armature G¹ this catch F³ serves to lift the carbon-supporting
rod C so as to establish the are. Upon the demagnetization of this electro-magnet
and the consequent descent of its armature and the levers F' the outer arm of the
catch comes into contact with a stop H, and on the further descent of the armature
and the levers F the catch will be caused to release the said rod and allow of the
descent of the upper carbon into contact with the lower carbon The pawl E will
not prevent this because the electro-magnet F in the derived circuit will have
become demagnetized whereby its armature is released The stop H consists of a
screw and hence is adjustable When the electro-magnet G subsequently becomes
magnetized the catch F is carried away from the stop H and again grips the upper
carbon rod. Its continued upward movement effects the lifting of the said rod
and the upper carbon so as to establish the arc.
I will now describe the main circuit. The electric current enters on the + wire
and proceeds thence to the box B, from this box it passes to the upper carbon rod C,
a spring contact piece J extending from the box and bearing against the said
carbon rod ensuring a free passage for the current. From this carbon rod the
current passes through the carbons, thence to the frame A, and from this frame by
a wire K, to the electro-magnet G and thence to the wire.
The derived circuit extends from the box B to a metallic lever L pivoted
thereto thence to a contact piece d, which is connected to the wire of the electro-
magnet F, thence through the insulating material in the box B to the wire. A pin
or projection e on the armature F" of the electro-magnet F, extends between two
shoulders ff with which the lever L is provided, and shifts it so that it will
impinge against the contact piece d, or be removed therefrom. The lever L is held
by friction in either position to which it may be adjusted until shifted again by
the said armature. Owing to the distance between the two shoulders f f' the
armature can move a considerable distance without shifting the lever L. It can
therefore move far enough to cause the jawl E to operate the ratchet or escapement
wheel D10 before it shifts the lever L so as to break the shunt or derived circuit.
When this circuit is broken the electro-magnet becomes demagnetized and its
armature descends and shifts the lever L so that it will reestablish the shunt
or derived circuit. Then if the arc is still too great, the operation will be
repeated.
I will now describe the cut-out circuit with which the lamp is provided. It
extends from the box B to the levers G and when these are depressed, from them to
a wire or other conductor M which is attached to, but insulated from, the box B,
From this conductor M it extends to a resistance coil N preferably located around
a tubular rod whereby the lamp is supported, and thence to the wire.
When the lamp is out of use the levers G2 carrying the armature Gl of the
electro-magnet G descend so as to make contact with the conductor M. Then the
electric current can flow through this cut-out circuit as well as through the main
circuit. The resistance-coil is of a resistance approximately corresponding to that
of the arc, but slightly less, hence if the lamp goes out for any reason other lamps
are not affected. When the lamp becomes operative again as for instance through
the feeding of a carbon from which a piece was broken, the electro-magnet G
becomes energized and the catch FS is caused to grip the rod of the upper carbon
and raise it so as to reestablish the arc. This catch is then maintained operative
as before explained.
It is obvious that the electro magnet G, when it attract its armature, first breaks
the cut out circuit so as to cut out the resistance-coil N, and afterwards with the
force due to the passage of practically the whole current through its coils raises the
upper carbon. On the elongation of the arc to such a degree as to materially vary
the resistance in the main circuit a greater quantity of the electric current passes
through the derived circuit. The consequent increase of power in the electro-
magnet F causes the pawl E to force down the upper carbon and shorten the arc

page_text: In the modification of this Invention shown in Figures 7 and 8 the parts
bearing the same letters which indicate parts of the lamp shown in the other
Figures need no further description. The main and shunt or derived circuits are
substantially the same as in the other lamp, but this lamp is not shown as provided
with a cut out circuit There is a slight difference in the shunt or derived circuit
which I will briefly advert to. In this lamp the lever L closes the derived circuit
by making contact with a conductor g. The lever L is provided with a contact-
piece h, made of spring metal, which, when the lever is depressed, yields to permit
the said lever to move farther than would be necessary to cause it to merely
impinge upon the said conductor When the lever L rises it moves a considerable
distance before its contact-piece leaves the conductor hence the said lever, before
breaking this circuit, has a considerable movement.
O indicates a frame adapted to slide vertically along suitable guides for a short
distance. This frame carries a pinion D' which engages with the rack D', and on
the same shaft with this pinion is a ratchet or escapement wheel D¹º. The move-
ment of this fram O is limited by an adjustable stop or screw P. The free end of
the levers G2 extend between the bottom of this frame and lugs q with which the
frame is provided hence when the levers are raised the frame will be raised also.
One of the levers G carries an escapement E', which controls the rotation of the
ratchet or escapement wheel D¹º. From the escapement E' extends an arm r to a
plate on the armature F' of the electro-magnet F in the shunt or derived circuit
When an electric current passes through the lamp the electro-magnet G becoming
energized, raised its armature, and elevates the frame O, thereby establishing the arc
between the carbons Afterwards when the consumption of the carbons and
consequent elongation of the arc materially increase the resistance in the main
circuit, a greater quantity of the electric current passes through the shunt or
derived circuit. Thereupon the electro-magnet F raises its armature and rocks the
escapement so as to permit of a partial rotation of the escapement wheel under an
impulse due to the weight of the upper carbon and its supporting rod. After the
escapement is thus operated by this armature, the latter, moving farther, breaks the
shunt or derived circuit; then the armature falls back and the escapement is shifted
in the reverse direction again closing the circuit If the arc is not sufficiently
shortened this operation is repeated.
It is essential in both the lamps which I have described that the electro-magnet F
in the shunt or derived circuit (should, as usual be of higher resistance than the
electro-magnet G in the main circuit
Having thus fully described the said Invention as communicated to me by my
Foreign Correspondent, and the manner of performing the same, I wish it understood
that I claim, in an electric lamp:-
First. The combination of an electro-magnet in the main circuit, an armature
therefor having connected to it means for gripping, raising and holding a rod
whereby the movable carbon is supported, a toothed rack on the said rod, one or
more gear-wheels in engagement with the said rack, a ratchet or other driving
wheel, an electro-magnet in a derived circuit, and an armature therefor having
connected to it a pawl or catch which, on the raising of this armature, will act on
such driving wheel to impart motion thereto, and thereby effect the feeding of the
said carbon, but at other times will leave the said wheel free.
Second. The combination of an electro-magnet in the main circuit, a cut-out
circuit, and a device controlled by the said electro-magnet and adapted to close the
cut-out circuit whenever an abnormal resistance or an interruption occurs in the
main circuit and to break the cut-out circuit whenever the main circuit is
re-established by the carbons coming together.
Third. The combination of an electro-magnet in the main circuit, a cut-out circuit
including a resistance approximately corresponding to that of the arc which will
be formed in the lamp, and a device controlled by the said electro-magnet and
adapted to close the cut-out circuit whenever an abnormal resistance or an

page_text: interruption occurs in the main circuit, and to break the cut-out circuit whenever
the main circuit is re-established by the carbons coming together.
Fourth. The combination of an electro-magnet in the main circuit, a cut-out
circuit, a device controlled by the electro-magnet and adapted, whenever the main
circuit is established by the carbons coming together, to first break the cut-out
circuit and then effect the separation of the carbons, whereby the cut-out circuit is
prevented from interfering with the electro-magnet in separating the carbons,
Fifth. The combination of a main circuit an electro-magnet therein and an
armature for the said magnet a movable carbon rod or bolder provided with a
rack, a shunt or derived circuit, an electro-magnet in the said derived circuit, an
armature for the electro-magnet last named, a device held in position by the
armature of the electro-magnet in the main circuit so that it can lock the movable
carbon-holder in position, a ratchet or escapement wheel, a device operated by the
armature of the electro-magnet in the shunt or derived circuit and controlling the
rotation of the ratchet or escapement wheel, and means, operated by the armature
of the electro-magnet in the shunt or derived circuit, whereby, after this armature
has moved a distance sufficient to shift the device which controls the rotation of
the ratchet or escapement wheel, the shunt or derived circuit will be broken so that
the armature will be permitted to return to its normal position, to again close the
said shunt or derived circuit.
In witness whereof I the said Henry Harris Lake have hereunto set my
hand and seal this Twelfth day of December in the year of our Lord
One thousand eight hundred and eighty two