AN IMPROVED ELECTRO-MECHANICAL APPARATUS FOR SUPPLYING AND ADJUSTING THE ELECTRODES USED IN THE PRODUCTION OF THE ELECTRIC LIGHT
Year: 1855

page_text: LETTERS PATENT to Henry Chapman, of Kingsland, in the County of
Middlesex, for the Invention of "AN IMPROVED ELECTRO-MECHANICAL
APPARATUS FOR SUPPLYING AND ADJUSTING THE ELECTRODES USED IN THE
PRODUCTION OF THE ELECTRIC LIGHT."
Sealed the 12th June 1855, and dated the 3rd April 1855.
PROVISIONAL SPECIFICATION left by the said Henry Chapman at the
Office of the Commissioners of Patents, with his Petition, on the 3rd
April 1855.
I, HENRY CHAPMAN do hereby declare the nature of the said Invention for
"AN IMPROVED ELECTRO-MECHANICAL APPARATUS FOR SUPPLYING AND ADJUSTING
THE ELECTRODES USED IN THE PRODUCTION OF THE ELECTRIC LIGHT" to be as
follows:-
One of the electrodes as for instance the lower one, is connected to the
armature of an electro-magnet in such a manner that on the passing of the
current of electricity through the coils of the electro-magnet, this electrode
may be drawn away from the other electrode to a suitable, distance for
producing the electric light. Thus on making the connection with the battery,
the light is at once produced. The upper electrode is connected to a chain or
band passing round a drum which is prevented from revolving by means of a
16483.

page_text: brake acting on a wheel in connection with the drum. This brake is governed
by another electro-magnet the coils of which are also traversed by the current
of electricity. When the current diminishes, from the gradual consumption of
the electrodes or from any other reason, the brake is liberated and the upper
electrode descends until by its approach to the lower electrode, the current
becomes increased and again puts on the brake. If either of the electrodes
should break or if from any other cause the light should be extinguished, the
lower electrode immediately rises and the upper one descends upon it and the
current, of electricity again passes, and the lower electrode is drawn down as
before, and the light is thus immediately re-established. The same electro-
magnet may be made to serve for both electrodes and instead of electro-
magnets, electric helices or other similar substitutes for electro-niagnets may
be employed, and the connection between the electrode and the brake may be
made by a rack in lieu of a chain or in any other suitable manner. In lieu
of giving the two motions to the two separate electrodes, these two motions
may, if preferred, be given to one of the electrodes only.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Chapman in the Great Seal Patent Office on the
19th September 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME I HENRY
CHAPMAN of Kingsland in the County of Middlesex send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria by Her Letters
Patent bearing date the Third day of April in the year of our Lord
One thousand eight hundred and fifty-five in the eighteenth year of Her
reign did for Herself Her heirs and successors give and grant unto me the
said Henry Chapman Her special licence that I the said Henry Chapman
my executors administrators and assigns or such others as I the said
Henry Chapman my executors administrators and assigns should at any time
agree with and no others from time to time and at all times thereafter during
the term therein expressed should and lawfully might make use exercise
and vend within the United Kingdom of Great Britain and Ireland the
Channel Islands and Isle of Man an Invention for "AN IMPROVED ELECTRO-
MECHANICAL APPARATUS FOR SUPPLYING AND ADJUSTING THE ELECTRODE USED IN
THE PRODUCTION OF THE ELECTRIC LIGHT" upon the condition (amongst others)
that I the said Henry Chapman by an instrument in writing under my hand

page_text: and seal should particularly describe and ascertain the nature of the said
Invention and in what manner the same was to be performed and cause the
same to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE that I the said Henry Chapman do hereby declare
the nature of the said Invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement thereof, reference being had to the accompanying Drawings and
to the letters and figures marked thereon, that is to say,
The Invention relates to the construction of apparatus for supplying and
adjusting the electrodes used in the production of the electric light by means
of a brake wheel and brake controlled by the current of electricity as herein-.
after described.
Figure 1 Sheet I. is an clevation of one of my improved apparatus for
producing the electric light. Figure 2 is an elevation of the same apparatus
without the sheath marked D in Figure 1. Figure 3 is a vertical section of
the same apparatus. The same letters refer to similar parts in each Figure.
A is a wooden box on which is fixed a hollow brass pillar B carrying an
arm or bracket C which supports a tube or cylindrical sheath D. Within the
sheath D is a smaller tube which is divided longitudinally into two parts E
and F, one of which E is fixed to the bracket C while the other part F is
kept in its proper position by small dowels or guide pins and is pressed
towards the part E by two springs e and f. Within the tube E. F. is placed
the carbon electrode or pole G which is fitted into a socket or tube H. The
electrode is thus capable of sliding up and down in the tube E. F. which is
kept in contact with it by the springs and serves to make the connection with
the voltaic pile or battery. I is a metal weight perforated to admit the tube
E. F. on which it slides. It is connected by a transverse pin to the tube or
socket H so as to move with the electrode. J is a chain attached to the
weight I and passing over pulleys a and b and down the pillar B-to the
barrel K. On the axis of this barrel is fixed a brake wheel L on which rests
the brake M turning on a pivot at c and carrying a piece of iron N which
forms the armature of an electro-magnet O. When the electric current passes
through the helices of wire of this electro-magnet, the armature N is attracted
by it and the brake' M is pressed upon the wheel L which is thus prevented
from turning round. The carbon electrode G is thus prevented from descending.
When however, the electric current ceases or diminishes, the brake is relieved
and the wheel L is thus allowed to revolve and the electrode G is lowered.
The pressure of the brake is regulated or adjusted by means of a spring and

page_text: screw d and the extent of the motion is adjusted by a screw g. The distance
of the armature from the magnet can also be adjusted by other screws h.
P is the lower carbon electrode which is fixed in a socket on the top of
a sliding rod Q which is connected to the armature R of another electro-
magnet S. The armature R is attached to a lever and is drawn away from
the magnet by a spring i and the extent of the motion is regulated by a screw j.
A piece of card is attached to the under side of the armature to prevent it
from touching the magnet. The electrode P is also supported by a spring T
which is sufficiently strong to support the weight of the upper electrode G and
the weight I. A wire is attached to the metallic support of the electrode,
and dips into a cup of mercury which is connected by another wire to a
socket U which receives one of the wires from the voltaic battery. The other
wire from the voltaic battery is secured in the socket V which is connected by
a wire to the helices of the electro-magnet O, which are connected to those of
the electro-magnet S, from which a wire proceeds to the pillar B.
The apparatus being thus arranged and the voltaic battery being in action
and the two electrodes G and P being in contact with each other, the effect is
as follows. The current of electricity from the voltaic battery passes from the
socket V round the helices of the electro-magnets O and S and up the pillar
B to the tube E. F. and through the carbon electrodes G and P and the
wire to the cup and thence through the socket U to the voltaic battery.
The electro-magnet O is thus caused to attract the armature N, and the
brake wheel L is prevented from revolving. The upper electrode G is thus
kept stationary. The electro-magnet S attracts the armature R and draws
down the lower electrode P to a sufficient distance from the upper one to
produce the electric light. The light is thus immediately produced by merely
connecting the voltaic battery to the apparatus.
The carbon electrodes are gradually consumed or volatilized during the
continuance of the light, and as the distance between them increases, the
resistance to the passage of the electricity increases, and the quantity of
electricity passing is diminished. The power of the electro-magnet diminishes
at the same time which however, does not affect the lower electrode, as the
electro-magnet S has still sufficient power to hold down its armature R.
The diminution of the power of the electro-magnet O relieves the brake M
sufficiently to allow the wheel L to revolve and the electrode G to descend.
The electrode G however, does not descend so much as to come in contact
with the lower electrode P, for as it approaches towards it, the current of
electricity increases and the brake is thus immediately pressed upon the wheel
and the descent of the electrode G is arrested.

page_text: The electrode G is thus constantly being advanced in proportion to the
consumption of the carbon, and the light is maintained with great regularity.
If a portion of one of the electrodes were to break off, or if from any other
cause the current were to be interrupted, the light would be extinguished. In
this case the armatures of the electro-magnets will be released, and the lower
electrode P immediately rises. The upper electrode descends upon it and
renews the contact, and the electricity again passes. The brake again comes
into action and keeps the upper electrode stationary, while the lower electrode
is drawn down to the proper distance and the light is thus immediately
reproduced. As the action of the electricity and magnetism is instantaneous,
these operations take place with very great rapidity so that there is scarcely
any interruption to the light even when the electrode is broken. On the
spindle of the brake wheel L is fixed a small ratchet wheel with a click or
pall which turns stiffly on a pin on the support of the spindle of the brake wheel.
This pall is pushed into the teeth of the ratchet wheel to prevent it from
revolving when the apparatus is being moved from place to place. The pall is
withdrawn when the apparatus is in use.
The sheath D may be made square or of other convenient form instead of
cylindrical. Figure 4 Sheet II. is a vertical section and Figure 5 is a
horizontal section of a square sheath arranged in a somewhat different manner
from that above described. D is the sheath, one side of which a is made to
open like a door.
I is the weight and J is the chain. The electrode G is
fitted into a short metul socket H which is secured to the weight I by a pin.
The electrode G passes through a short tube E. F. divided longitudinally into
two parts, one of which E is fixed to the sheath D while the other part F is
pressed against it by a spring fattached to the door a. When it is required
to insert a new electrode the door is opened and the part F is taken out.
The socket H is also disconnected from the weight by withdrawing the pin.
The electrode is fitted into the socket H and it is then inserted in its place
and attached to the weight I by the pin. The half tube F is then put in its
place and the door is closed and secured by a catch. The spring f is thus
pressed against the tube F and the apparatus is ready for use.
In lieu of connecting the electrode to the brake wheel by means of a chain
and barrel, the connection may be made in any other suitable manner, and
the electrodes may also be placed in borizontal or inclined positions, instead of
in a vertical position. Thus, in Figure 6 Sheet II is shewn one of my
apparatus in which the electrodes G and P are placed horizontally and a rack
J and pinion K are employed in lieu of the chain and barrel. The electrode G
is fitted into a socket H at the end of the rack J, and slides through the

page_text: metallic bracket C while the
The pinion K which drives
divided tube F, one half of which is fixed to the
other half is pressed towards it by a spring f.
the rack J is fixed on the spindle of the brake wheel L. The brake M carries
the armature N of the electro-magnet O, and is regulated and adjusted by the
spring and screw d, and by the screws g and h. On the spindle of the brake
wheel L is a barrel n on which is wound a chain o carrying a weight I. This
weight has a constant tendency to advance the electrode G but is controlled
by the brake. The rack is supported upon rollers a b to enable it to move
freely. The opposite electrode P slides in a fixed support 9, and is fixed in a
metallic socket which is connected to the bent lever which carries the
armature R of the electro-magnet S. The arınature is pressed away from the
magnet by an adjustable spring at i, and the extent of its motion is regulated
by a screw j as in the apparatus above described. The armature is prevented
from touching the electro-magnet by the interposition of a piece of card. A
wire is attached to the socket p and dips into a cup of mercury which is
connected to one of the wires proceeding from the voltaic battery. The other
wire from the battery is connected to a socket. V, from which a wire proceeds
to the helices of the electro-magnet O which are connected to those of the
electro-magnet S from which a wire proceeds to the bracket C.
The apparatus being thus arranged, the current of electricity from the voltaic
battery passes from the socket V round the helices of the electro-magnets O
and S and through the bracket C and tube F and through the carbon
electrodes G and P and the wire k to the cup and thence back to the voltaic
battery. The brake M is thus pressed on the brake wheel L, and the electrode
G is kept stationary while the electrode P is drawn back to a sufficient distance
to produce the electric light. As the electrodes are consumed and the distance
between them increases, the flow of the electricity diminishes and the brake is
thus relieved. The electrode G is then advanced a little by the weight I and
thus the supply of the electrode is kept up. If the light should become
extinguished, the electrode P immediately advances and the electrode G
advances and comes in contact with it. The electricity then passes and the
electrode P is drawn back and the light reproduced.
In lieu of giving the two motions to the two electrodes, both motions may
be given to one electrode, and the other may then be fixed. Figure 7
Sheet II. is a side view partly in section of an apparatus constructed with
this modification. The parts marked B. C. D. E. F. G. J. K. L. M. N. O. P.
p. c. d. g. h. are similar to those similarly marked in the apparatus shewn in
Sheet I. Figures 1. 2. and 3. The chain J before ascending the pillar B is
however carried round a pulley W on the lever which carries the armature

page_text: R of the electro-magnet S. The lever is drawn away from the electro-
magnet by a spring i, and the extent of its motion is regulated by a screw j,
and a piece of card is interposed between the armature R and the electro-
magnet S to prevent contact.
One of the wires from the voltaic battery is secured in a socket V from
which a wire procceds to the helices of the electro-magnet S, which are con-
nected to those of the electro-magnet O, from which a wire proceeds to the
metallic pillar B, which conveys the electricity to the electrode G which is
arranged in the manner shewn in Sheet I. A wire connects the metallic
socket p of the electrode P with a socket U.
The two wires from the voltaic battery are connected to the two sockets U
and V. The electric current passes from the socket V round the electro-
magnets S and O, through the pillar B to the electrode G, and through the
electrode P and wire k to the socket U and back to the voltaic battery. The
armatures of the electro-magnets are attracted, and the brake M is thus pressed.
on the brake wheel L which is prevented from turning round. The arma-
ture R is drawn down and the pulley W is thus depressed, and the electrodo
G is thus raised to a proper distance for producing the light. As the electrodes
are consumed and the distance between them increases, the flow of electricity
diminishes, and the brake is thus relieved. The electrode G then descends a
little, and the flow of the electricity being thus increased, the brake is
immediately brought into action and the motion of the electrode ceases. If
the light is extinguished, the armature R and pulley W rise, and the brake M
is relieved. The electrode G then descends upon the electrode P and the
current of electricity again passes. The brake M is immediately brought into
action and the brake wheel L is held fast while the armature R and pulley W
are drawn down to a sufficient distance for again producing the light. As the
lower electrode is gradually consumed, the position of the light descends.
cases in which this variation in the position is objectionable, a clock-work motion
may be applied to the electrode P so as to raise it at the same rate at which
it is consumed. The electrode in connection with one pole or wire of the
battery is found to consume faster than that in connection with the other pole
of the battery, and I prefer to connect the battery to the apparatus so that the
upper electrode or that which is regulated by the brake may be consumed
the fastest.
In
In Figure 8 I have shewn a portion of an apparatus constructed in a similar
manner to that shewn in Figure 7 with some additional parts for giving motion
to the lower electrode. The socket p of the lower clectrode P is fixed on
the upper end of a rack X which is driven by a pinion Y on the spindle of a

page_text: wheel Z which is driven by a pinion s on the spindle of the brake wheel L.
By this arrangement whenever the brake M is relieved, the lower electrode P
is raised a little as the upper one descends. The wheels and pinions are so
proportioned that the motion of the lower electrode may be about one quarter
of that of the upper electrode or in such other proportion as may agree with
their relative rates of consumption. The position of the light is thus kept
stationary. The pinion Y is not fixed upon its spindle but fits upon it
sufficiently tight to enable it to move the rack. It can be turned round by
hand so as to adjust the electrode and to lower the rack when it becomes
necessary to insert a new electrode. The rest of the apparatus is similar to
that shewn in Figure 7. The weight which is attached to the upper electrode
is made sufficiently heavy to give motion. to both electrodes, or the lower
electrode may be separately balanced by means of a chain z attached to the
rack X and carried over a pulley and having a weight w attached to its
extremity.
Figure 9 is a view of a portion of a somewhat similar arrangement adapted
for the apparatus shewn in Sheet I. In this case the spindle of the wheel Z
and pinion Y is supported upon a lover which turns loosely upon the spindle
of the brake wheel L or upon a fulcrum concentric with it. The lever r
carries the armature R of the electro-magnet S and is adjusted by a spring i
and screw j as in the other apparatus above described. The chain J from the
barrel K is conducted round a fixed pulley t and then up the pillar as in the
apparatus shewn in Sheet I. The rest of the apparatus is similar to that
shewn in Sheet I. and is therefore omitted in this Figure to prevent confusion.
When the voltaic battery is connected with the apparatus, the brake M is
pressed upon the wheel L by the action of its electro-magnet (which is not
shewn in the Drawing) and the wheel L and the pinion s and the barrel K
are thus prevented from revolving. The armature R is attracted by the
electro-magnet S, and draws down the lever r with the wheel Z and pinion Y,
and thus draws down the rack X so as to separate the electrodes sufficiently
to produce the light. As the distance between the electrodes increases, tho
current of electricity diminishes and the brake M is relieved. The brake wheel
then turns round a little and lowers the upper electrode and at the same time
raises the lower electrode to a proportionate extent. The current then increases
and the brake is again pressed upon the wheel. If the light is extinguished,
the lever rises up, and raises the lower electrode. The brake wheel being
released, revolves and lowers the upper electrode and at the same time raises
the lower electrode until the two electrodes come in contact. The electric
current then passes, and. the brake is pressed upon the brake wheel, and the

page_text: armature R is drawn down and the lower electrode is thus drawn down to a
sufficient distance to produce the light. The effect of these arrangements
is therefore the same as that of those above described with the additional
advantage of keeping the position of the light constant or nearly so.
In these arrangements the connection between the voltaic battery and the
electrode P may be made by means of a wire dipping into a cup of mercury
as in the apparatus shewn in Sheet I., or by means of a divided tube similar
to that employed for the electrode G in the other arrangements of the appa-
ratus, or by means of the metal sockets or guides through which the rack X
works.
Thus
The details of the construction of my apparatus admit of variation.
the two armatures N and R may be acted on by one and the same electro-
magnet, instead of employing two separate magnets for that purpose. In lieu
of electro-magnets other substitutes for electro-magnets (such as electric helices
or coils of wire traversed by the current of electricity and having a moveable
iron core,) may be employed. In lieu of placing the brake wheel upon the
spindle which carries the barrel or pinion which gives motion to the electrode,
the brake wheel may be mounted on a separate spindle connected with the first
by one or more wheels and pinions. The brake wheel may thus make several
revolutions for one revolution of the spindle of the barrel or pinion and an
electro-magnet of small power will be sufficient to work the brake. Multiplying
wheels and pinions may also be employed to communicate the motion from
the spindle of the barrel or pinion to the spindle of a fan or fly, so that the
resistance of the air to this fly may retard the motion and cause the electrode
to advance more slowly. In lieu of toothed wheels and pinions, pulleys and
bands or chains may be employed to communicate the various motions. In
a similar manner in lieu of employing a rack and pinion for raising or moving
the electrode, a pulley with a chain or band, or a screw may be employed for
that purpose.
I have mentioned the voltaic battery as being employed as the source of
electricity, but any
other suitable and sufficiently powerful source of electricity,
such as a magneto-electrical machine, may be employed. My Invention does
not relate to the mode or modes of obtaining the supply of electricity, but to
the apparatus for supplying and adjusting the electrodes used in the production
of the electric light.
Having now described the nature of my Invention and in what manner the
same is to be performed I wish it to be understood that what I claim is-
Firstly the constructing apparatus for supplying and adjusting one or both
the electrodes used in the production of the electric light by means of a brake

page_text: wheel and a brake controlled by the current of electricity, as herein-before
described.
Secondly I claim the peculiar combinations of parts forming the apparatus
and the various modifications thereof herein-before described.
In witness whercof I the said Henry Chapman have hereunto set, my
hand and seal this Eighteenth day of September in the year of our
Lord, One thousand eight hundred and fifty-five.
Witness,
CHARLES COWPER
20 Southampton Buildings
Chancery Lane.
HENRY CHAPMAN. (L.S.)