IMPROVEMENTS IN ELECTRIC LAMPS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Charles Godfrey Gumpel
at the Office of the Commissioners of Patents on the 9th June 1882.
CHARLES GODFREY GUMPEL of No 49 Leicester Square in the County of
Middlesex IMPROVEMENTS IN ELECTRIC LAMPS"
«
My invention relates to construction and arrangement of electric lamp with
automatic feed of the electrodes and formation and regulation of the arc in a
simple and compact form as I will describe. The one electrode or carbon may be
fixed, the other only being moveable, or when it is desired to maintain the arc in
one position, both electrodes may be moved proportionally to their rate of con-
sumption by connecting them by cords or wires passing round pullies, as is well
understood, the feeding and regulating apparatus being however applied only to
one of them which for clearness of description I will assume to be the upper carbon
of a vertical lamp. This carbon passes freely down through the centre of a solenoid
which has its coil in the lamp circuit and below this solenoid it is clamped between
two rollers. One of these rollers is mounted in a light vertically sliding frame
and has on its axis a feed wheel. The other roller is mounted on the vertical arm
of a bell crank lever which is pivotted on the light frame and has its horizontal
arm linked to the iron core of the solenoid above mentioned. The feed wheel may
be toothed as a ratchet wheel having its teeth engaged by a pawl or it may have
a smooth periphery engaged by a clamping pawl such as is used for the silent feed
in many known machines. The pawl is linked to the core of a second solenoid
which has its coil of high resistance in a bypass circuit connecting the conductors
to and from the lamp. These parts operate as follows: When no current passes,
the solenoids are inert consequently the core of the first descends withdrawing the
roller of the bell crank and so leaving the upper carbon free to descend till it
meets the lower carbon. When a current passes the first solenoid becoming excited
attracts its core upwards, and this moving the bell crank presses the roller of the

page_text: bell crank against the carbon which thus becomes clamped between the two
rollers. The father ascent of the core raises the light frame and the clamping
rollers along with the carbon withdrawing it from the lower carbon, so that the
arc is formed between the carbons. When by the consumption of the carbons the
distance between them gives the are more than its normal resistance, a larger
portion of the current passes through the coil of the second or bypass solenoid and
it attracts its core upwards. The pawl attached to this core is thus made to turn
the feed wheel and its roller partly round so as to advance the carbon. Thus,
according as the resistance of the are varies, the one solenoid core acts by clamping
and withdrawing or by liberating the carbon, and the other core acts by turning
or releasing the feed wheel and so advancing or ceasing to advance the carbon,
so that the arc is automatically maintained nearly constant. Instead of employing
a vertically sliding frame as above described to carry the one roller and feed wheel
and the bell crank for the other roller, these parts may be carried on a lever arm
pivotted to the framing of the lamp and the bell crank may be worked by another
arm carrying the armature of an electromagnet which may be substituted for the
first solenoid. The carbons instead of being arranged vertically, in which case
they are preferably counterbalanced, may be arranged horizontally or in other
attitudes the clamping rollers and feeding mechanism nevertheless operating as
above described. The end of one of the carbons may be held in a metallic socket,
which when the carbon is nearly all consumed, makes contact with a spring and
so closes the external circuit excluding the lamp from it, until this contact is
broken for the introduction of a fresh carbon
"
↓
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Godfrey Gumpel in the Great Seal Patent Office on
the 8th December 1882.
CHARLES GODFREY GUMPEL of No 49 Leicester Square in the County of
Middlesex " IMPROVEMENTS IN ELECTRIC LAMPS "
My invention relates to a construction and arrangement of electric lamp with
automatic feed of the electrodes and formation and regulation of the arc in a
simple and compact form as I will describe. The one electrode or carbon may be
fixed, the other only being movable, or when it is desired to maintain the arc in
one position, both electrodes may be moved proportionally to their rate of con-
sumption by connecting them by cords or wires passing round pullies, as is well
understood, the feeding and regulating apparatus being however applied only to
one of them which for clearness of description I will assume to be the upper
carbon of a vertical lamp. This carbon passes freely down through the centre of a
solenoid which has its coil in the lamp circuit and below this solenoid it is clamped
between two rollers. One of these rollers is mounted in a light vertically sliding
frame and has on its axis a feed wheel. The other roller is mounted on the vertical

page_text: arm of a bell crank lever which is pivotted on the light frame and has its horizontal
arm linked to the iron core of the solenoid above mentioned. The feed wheel may
be toothed as a ratchet wheel having its teeth engaged by a pawl or it may have a
smooth periphery engaged by a clamping pawl such as is used for the silent feed
in many known machines. The pawl is linked to the core of a second solenoid
which has its coil of high resistance in a by-pass circuit connecting the conductors
to and from the lamp. These parts operate as follows:-When no current passes,
the solenoids are inert consequently the core of the first descends--withdrawing
the roller of the bell crank and so leaving the upper carbon free to descend till it
meets the lower carbon. When a current passes the first solenoid becoming excited
attracts its core upwards, and this moving the bell crank presses the roller of the
bell crank against the carbon which thus becomes clamped between the two rollers.
The farther ascent of the core raises the light frame and the clamping rollers along
with the carbon withdrawing it from the lower carbon, so that the arc is formed
between the carbons. When by the consumption of the carbons the distance
between them gives the arc more than its normal resistance, a larger portion of the
current passes through the coil of the second or by pass solenoid and it attracts its
core upwards. The pawl attached to this core is thus made to turn the feed wheel
and its roller partly round so as to advance the carbon. Thus, according as the
resistance of the arc varies, the one solenoid core acts by clamping and withdrawing
or by liberating the carbon, and the other core acts by turning or releasing the
feed wheel and so advancing or ceasing to advance the carbon, so that the arc is
automatically maintained nearly constant. Instead of employing a vertically
sliding frame as above described to carry the one roller and feed wheel and the
bell crank for the other roller, these parts may be carried on a lever arm pivotted
to the framing of the lamp and the bell crank may be worked by another arm
carrying the armature of an electro-magnet which may be substituted for the first
'solenoid. The carbons instead of being arranged vertically in which case they are
preferably counterbalanced, may be arranged horizontally or in other attitudes the
clamping rollers and feeding mechanism nevertheless operating as above described.
The end of one of the carbons may be held in a metallic socket, which when thie
carbon is nearly all consumed, makes contact with a spring and so closes the
external circuit excluding the lamp from it until this contact is broken for
the introduction of a fresh carbon.
Fig 1 of the accompanying drawings is a vertical section, and Fig 2 is a plan on
XX of one form of electric lamp according to my invention. C and C¹ are the
carbons, the lower C' fixed in its holder and the upper C fixed to a guided
holder c which is attached to a rod or tube A that passes up through the middle of
a solenoid B, and is counterbalanced by a weight a connected to it by cords passing
over pullies. Within the solenoid B is fitted free to slide a non magnetic tube D
carrying a light frame d on which is pivotted a bell crank lever E carrying one of
the hollowed pressing rollers e, and in which is mounted the other pressing roller f
having on its axis a feed wheel F. The horizontal arm of the bell crank E is linked
to an iron tube G.which forms the moveable core of the solenoid B. A canting
pawl h attached to the core H of the solenoid K. engages the the rim of the wheel F.
The descent of the frame d is limited by a stop b, and a spring s acts as a brake to
the feed wheel F. When the carbons C C³ are in contact and the lamp is put in
circuit, the current passes freely through the carbons and also through the coil
of B which is of low resistance in the lamp circuit. The core G being then
attracted upwards by moving the bell crank E causes the roller e to press against
the rod A so that the rod is gripped between e and f and by the continued ascent
of the core G the rod A and holder c are raised lifting the upper carbon C away
from the lower carbon and establishing the arc between C and C₁. When owing
to consumption of the carbons the resistance of the arc increases, then a greater
portion of the current passes through the coil of K which is of high resistance in a
by-pass circuit. The core H being then drawn upwards its pawl h clamping the
rim of the wheel F turns it partly round in the direction of the arrow causing the

page_text: carbon C to descend. When the resistance of the arc is thus reduced the solenoid K
becomes comparatively inert and its core H descends the pawl h slipping along the
rim of F. Thus by the action of the solenoids B and K the regulation and feed of
the carbons are automatically effected. When the carbons are nearly consumed
sockets at the ends of the holder c make contact with springs c¹ short circuiting the
lamp current. Fig 3 shews a modified construction of the regulating apparatus
according to which the gripping rollers e and fare mounted on a kind of toggle
joint pivotted to the frame d. The parts in Fig 3 corresponding with those in Fig 1
are marked by similar letters. In order to give the rollers e and fadditional
gripping power I prefer to divide the core G into two parts connecting the upper
part G₁ to the tube D so that when the solenoid B acts both parts are attracted
towards each other. Fig 4 shews a modified construction according to which the
gripping rollers e fare mounted in a toggle joint linked to a lever L carrying the
armature of an electro-magnet B having its coil of low resistance in the lamp
circuit. The feeding solenoid K having its coil of high resistance in the by-pass
circuit may with advantage have below it a coil K' of low resistance in the lamp
circuit as by this arrangement the ascent and descent of the feeding core H are
more certainly and fully effected by variations in the currents passing through the
two coils K and K', and thus the apparatus is rendered more sensitive.
In the modification shewn by Fig 5 a lever L carrying the armature of the
electro-magnet B is linked to a bell crank M which carries one gripping roller f
with the feed wheel F, and which is itself pivotted on a frame N carrying the
gripping rollers e e².
Having thus described the nature of my invention and in what manner the same
is to be performed, I claim :-
:-
Effecting the feed and regulation of the carbons of an electrical arc lamp
automatically by the action of two solenoids or electro-magnets, one of which
having its coil in the lamp circuit causes one of the carbons or a rod attached to it
to be gripped between rollers and to be raised or to be released and lowered whilst
the other by means of a pawl and ratchet or its equivalent causes one of the gripping
rollers to be turned so as to advance the carbon, substantially as herein described.
In witness whereof I the said Charles Godfrey Gumpel have hereunto set
my hand and seal this Seventh day of December in the year of our Lord
One thousand eight hundred and eighty-two.