IMPROVEMENTS IN ELECTRIC LIGHTING APPARATUS
Year: 1879

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN ELECTRIC LIGHTING APPARATUS." A communication
from abroad by Jules Puvilland and Toussaint Raphaël, both of Paris, France,
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 27th May 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN ELECTRIC LIGHTING
APPARATUS." [A communication from abroad by Jules Puvilland and Toussaint
Raphaël, both of Paris, France.]
This Invention relates to an improved electric lighting apparatus in which
revolving annular carbons are employed, these carbons being of considerable length
but occupying only a small space, they therefore permit of obtaining a regular and
continuous light for as long a time as may be desired without being renewed. The
said carbons revolve as the points between which the light is developed wear away,
these points being thereby caused to remain continually at practically the same
distance from each other.
The mechanism which regulates the relative position of the carbons is very simple,
and operates automatically by the aid of the parts hereinafter described.
In carrying the said Invention into practice I provide two carbons of circular or
annular form, there being a space or break in each one, that is to say, it does not
form a complete circle. They are fixed in holders which grasp and maintain that
extremity of each carbon which is not the point end, these holders being mounted

page_text: upon axes held by fixed supporting pieces. A groove permits of regulating each
carbon-holder at variable distances from the axis according to the radius of the
carbons which it is desired to employ. The two axes upon which the carbon-holders
are placed, and which together form the suitable angle to maintain the planes in
which the carbons are situated at an angle of about from 60 to 70 degrees with regard
to the horizontal plane, are each provided with two pulleys of suitable diameter.
Upon the pulleys there are metallic cords or chains, one of which tends to cause the
axis to turn in one direction, whilst the other tends to cause it to turn in the
opposite direction. It will therefore be understood that every movement of the
pulleys will be communicated to the carbons, and that according to which direction
the pulleys are turned the carbon points will approach or recede from each other.
The two metallic cords or chains which tend constantly to bring the points of the
carbons together, and under whose action the latter are caused to turn continuously,
are joined together at a convenient position and so become one, which is operated
by a weight whose position on a lever may be regulated. This lever is pivoted or
jointed to a fixed part of the lamp, and the weight may be caused to take a suitable
course. The two cords or chains which tend to separate the points of the carbons
by causing the axes which carry the carbon-holders to turn in the direction opposite
to their ordinary movement are carried, together or separately, to a piece of soft
iron, either solid or hollow, which is so arranged that it may move longitudinally
inside a metallic tube with which it is placed in contact by a cushion or rubber, and
around which is coiled a copper wire which constitutes a solenoid arranged con-
sequently around the said interior piece of soft iron; the greater the intensity of
the current which traverses the coils of the bobbin, the farther the piece of iron
penetrates into the bobbin. The current arriving at one side of the apparatus goes
into the mass and passes to one of the carbons through the axis and holder in
connection therewith. The light is developed between the points of the two
carbons, then the current returns through the other carbon, passes to the holder of
the latter, and thence through its axis and to the two pulleys in connection there-
with; then it passes through the metallic chain or cord which is around them to
the aforesaid piece of soft iron, whence it goes through the cushion or rubbing
connection to the metallic tube, and to the wire of the bobbin which terminates on
this tube; this wire finally conducts the current to the point of the apparatus where
it leaves the same. The fixed support or frame to which the carbon-holders are
attached is suitably insulated, as also any other parts requiring it, in order to
prevent the current from passing in any other direction than the one desired.
If the carbons should approach too near to each other the current flows more
readily from one to the other, acts with increased intensity in the coils of the bobbin,
and the piece of soft iron descends farther into the same, drawing with it the
metallic cords attached to the said piece, which cords operate their respective pulleys
in such a manner as to cause the carbons to turn in a direction contrary to their
ordinary movement, that is to say, in such a direction as to withdraw the points
farther from each other. It will thus be seen that the equilibrium is constantly
maintained between the action of the weight and that of the bobbin of the aforesaid
piece of soft iron.
The carbons may be as long as desired, as when greater length is required it is
only necessary to increase the diameter of the ring of carbon. It will also be
understood that by suitably arranging the axes around which they turn I may
employ carbons with several coils, and having consequently a much greater length
with the same diameter. To make use of this arrangement all that is necessary is
to provide metallic parts to cause the points of the carbons to remain always exactly
opposite each other.
The electric lamp or lighting apparatus above described may be arranged upon
any kind of support; it may even be suspended, in which case, if required to turn
round, it is only necessary to suitably equalize the respective operations of the
weight and the piece of soft iron. The said weight may, if desirable, be replaced

page_text: by one or two spiral springs acting upon a lever jointed at one end or at its
centre.
In order to render the movement of the carbons still more regular and certain I
may equalize more or less completely the weight of the carbon-holders by employing
for this purpose suitable arrangements.
I prefer instead of making the current travel the whole length of the carbons to
cause it to act near the point by the aid of a suitably arranged fixed cushion or
similar device against which the carbons will turn.
In all cases I employ the same kind of carbons which constitute an important
feature of the said Invention.

page_text: These motor-weights are free to move in the tubes j, j, arranged to enclose them
and placed at the sides of a tube k fixed in the axis of the apparatus and containing
the electro-magnet for producing when necessary the separation of the carbons as
above described.
The single bobbin of this electro-magnet is composed of wire sufficiently large to
prevent any accident from the passage of the current. One of the extremities of
the wire is connected with the source of electricity (preferably a machine producing
reverse currents) by the conductor m, and the other end is united to the core n of
the bobbin which is insulated from the main body of the apparatus. The part o of
the latter is extended upwards in such a manner as to carry the armature P which
is jointed to it, and whose extremity is fastened to a rod q attached to a balance
lever suitably equipoised by a counterweight & and forming part of the separating
mechanism.
This balance-lever is arranged to oscillate upon pivots t, t¹, one of which is
insulated and turns in an ivory bush 2, Figure 2, whilst the other communicates
freely with the carbon carrier b¹, and consequently with the carbon a¹ whose support
is insulated at v, as shown in Figure 1.
The result of this arrangement is that the current which has traversed the spirals
of the bobbin passes through the part o of the said bobbin into the armature and
then to the axis of the balance-lever, and to the carbon a¹. The other conductor
leading from the machine simply communicates with the main body of the apparatus
which puts it in communication with the carbon-holder b and carbon a.
It will thus be seen that the circuit can only be closed between the points of the
carbons from which the luminous arc is emitted.
If the carbons approach each other too closely the current passes more easily
between them and acts with a groater intensity in the spirals of the bobbin, and
the armature is attracted, the balance lover which it controls then oscillates and
causes the pivots with which it is connected to turn to a certain extent.
The said pivots are provided with bosses w serving as cranks, which have con-
nected with them levers x, x¹, that actuate the separating pawls y, y¹. These pawls
which are maintained by springs z, z¹, in contact with the ratchet wheels A, A¹,
keyed upon the axes c, c³, of the carbon holder are constructed in such a manner as
to permit the free passage of the teeth of the wheels so long as the armature is not
attracted by the magnet. As soon as the latter acts the pawls engaging in the
teeth of the said wheels cause the axes of the carbon holders to turn in a direction
opposite to that of their ordinary movement, thereby producing the necessary
separation of the points. The equilibrium is therefore continually maintained by
the action of the motor-weights and that of the bobbin upon its armature.
It will be understood that the length of the carbons may be increased to any
desired extent which will not inconveniently augment the diameter of the carbon
rings.
It will also be understood that by suitably arranging the axes around which the
carbons turn I am enabled to so form the carbons as to present several spirals, and
the said carbons will consequently have a much more considerable development
without increasing their diameter. When such spiral carbons are used suitable
mechanical appliances are employed to ensure the proper action of the same.
The motor-weights herein before described may be dispensed with and replaced by
other suitable devices when desired.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performing the same, I wish it understood
that I claim,
First. For the production of electric light the employment of annular carbons
which before commencing toburn constitute an almost complete circle, or a series
of circles, in the form of a spiral, substantially in the manner and for the purpose
set forth, and as shewn in the accompanying Drawing.
Second. A lamp constructed as herein described, and shewn in the accompanying
Drawing, in which the carbons are caused to turn by a suitable motor in such a

page_text: manner that their points are kept always opposite to each other, and in which a
magnet or bobbin traversed by the light-producing current acts to prevent their
approaching each other too closely, so that there is no perceptible variation in their
distance apart, all as and for the purposes specified.
In witness whereof, I, the said William Robert Lake, have hereunto set &
my hand and seal, this Twenty seventh day of November, in the year of
our Lord One thousand eight hundred and seventy nine.
T7M
DAPT TATT 1701