IMPROVEMENTS IN APPARATUS AND MECHANISM FOR ELECTRIC LIGHTING
Year: 1879

page_text: LETTERS PATENT to Gustavus Palmer Harding, of Paris, Engineer, for the
Invention of "IMPROVEMENTS IN APPARATUS AND MECHANISM FOR ELECTRIC
LIGHTING."
Sealed the 7th May 1880, and dated the 11th November 1879.
PROVISIONAL SPECIFICATION left by the said Gustavus Palmer Harding
at the Office of the Commissioners of Patents on the 11th November 1879.
GUSTAVUS PALMER HARDING, of Paris, Engineer. "IMPROVEMENTS IN
APPARATUS AND MECHANISM FOR ELECTRIC LIGHTING."
These improvements in apparatus and mechanism for electric lighting relate to
the position and feed of the carbons or electrodes and to the relighting of the
electrodes when extinguished.
The carbons are placed horizontally, preferably one above the other, with a
current having the necessary tension to form the arc at the extremities of the
carbons. A shunt is arranged to bring the carbons together and form contact for
relighting, for which purpose one of the tubes holding the carbon is movable.
The armature can then have a special movement which brings the carbons together
gradually, and this arrangement can be utilised for several other objects. I
employ the expansion by heat of a metallic wire for feeding the carbons as they
consume. This expansion I equally employ for liberating a weight or for acting a
ratchet, a spring, a lever, or a can, by the aid of which the carbons are fed the
given rate, the feed being thus regular and definite.
The carbons are placed in two tubes or within a set of rollers, one above the
other, the carbons being fed by a cap at the end holding the two carbons, the cap
being pushed forward by a cord acting over a pulley, a spring, or other force con-
trolled by the expansion of a metallic wire or coil of wire, which, becoming heated,
releases the force, and the carbons are moved beyond the sphere of the action of
the beated arc upon the wire. In one case a portion of the current passing through

page_text: the carbons is diverted to feed the electrodes by the current acting on an armature
which moves a cam or ratchet so as also to project the carbons forward beyond the
influence of the diverted current, or the current may be arranged to give a con-
tinuous feed by any suitable mechanism.
To light the lamp, or in case of extinction to reform the arc, one of the tubes is
made moveable and in connection with an armature acted on by an electro magnet,
through which the current passes so soon as the current finding no outlet through
the carbons seeks a passage through the electro magnet or shunt; it then brings the
two carbons together at the point, and the light is reestablished, and the current
finding its way through the carbons the armature ceases to act.
The adjustment of the parallel carbons for distance is made by a sliding arm
and screw holder or by a rack and pinion, and is contrived so as to work from the
outside of the lamp.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Gustavus Palmer Harding in the Great Seal Patent Office on the
11th May 1880.
GUSTAVUS PALMER HARDING, of Paris, Engineer.
APPARATUS AND MECHANISM FOR ELECTRIC LIGHTING."
"IMPROVEMENTS
IN
These improvements in apparatus and mechanism for electric lighting relate to
the position and feed of the carbons or electrodes and to the relighting of the
electrodes when extinguished.
The carbons are placed horizontally, preferably one above the other, with a
current having the necessary tension to form the arc at the extremities of the
carbons. A shunt is arranged to bring the carbons together and form contact for
relighting, for which purpose one of the tubes holding the carbon is moveable.
The armature can then have a special movement which brings the carbons together
gradually or otherwise, and this arrangement can be utilized for several other
objects. I employ the expansion by heat of a metallic wire for feeding the carbons
as they consume, and from experiments made during the term of my Provisional
Protection I sometimes carry this expansion so far as to fuse the wire and utilize
this fusion of the wire as a means of bringing into play the meads of advancing the
carbons as they consume; in place of wire I use stops of woods or glass, the heat of
the carbons in the latter case softening the glass so as to allow it to bend and to
pass the stop and put the machinery in motion to bring the carbons forward.
This expansion or fusion I equally employ for liberating a weight or for acting a
ratchet or spring, a lever, or a cam, by the aid of which the carbons are fed the
given rate, the feed being thus regular and definite.
The carbons are placed in two tubes within a set of rollers, one above the other,
the carbons being fed by a cap at the end holding the two carbons, the cap being
pushed forward by a cord acting over a pulley, a spring, or other force controlled
by the expansion of a metallic wire or coil of wire, which, becoming heated, or
even fused, releases the force, and the carbons are moved beyond the sphere of
the action of the heated are upon the wire. In one case a portion of the current
passing through the carbons is diverted to feed the electrodes by the current acting
on an armature which moves a cam or ratchet so as also to project the carbons
forward beyond the influence of the diverted current, or the current may be
arranged to give a continuous feed by any suitable mechanism..
To light the lamp, or in case of extinction to reform the arc, one of the tubes is
made moveable, and in connection with an armature acted on by an electro
magnet, through which the current passes so soon as the current finding no outlet
through the carbons seeks a passage through the electrode magnet or shunt, it
then brings the two carbons together at the point, and the light is reestablished,
and the current finding its way through the carbons the armature ceases to act.
The adjustment of the parallel carbons for distance is made by a sliding arm and
screw holder or by a rack and pinion, and is contrived so as to work from the
outside of the lamp.
The electrode acting on a ratchet which, while it works forward the carbons,
also brings round a fusible stop, which at a given point stops the ratchet and rests
partially on or over carbons; when the carbons burn to the stop it fuses. The
ratchet again works until another stop is reached. But the lamp will act without
any automatic arrangement for feeding, as the carbons can be pushed on by hand,
and are so fitted as to keep their parallel and respective positions. A consumable
but not inflammable non conductor, as paper soaked in such solutions as alum or
tungstate of soda, between the carbons prevents the arc from running up, and
when consumed does not interfere with the current (or passage of it).
In the Drawings forming part of this Specification, and showing some of the

page_text: plans of carrying out the Invention, Figure 1 is a plan; Figure 2, a lateral eleva-
tion partly in section; Figure 3, a front view; Figure 4, a front elevation in
section of the line A, A, Figure 1; Figure 5, same view, the axle and the armature
being turned round; Figures 6, 7, 8, a modification of part of the mechanism
Figure 9 is a modification of the mounting of the mechanism; Figure 10, plan
of the stop mechanism; Figure 11, elevation of parts shown in Figure 10.
The two carbons 1 and 2 are arranged parallelly, the one over the other, and
the voltaic arc is produced between the two extremities, the carbons being con-
sumed. The carbons are held by the tubes 3 and 4, in which they can slide
horizontally. The tube 3 is mounted in a fixed manner by the piece 5, the
brackets 6, and the chair or frame 7, whilst the tube 4 fixed to the piece 8 is
articulated, so that the carbon 2 adapted to it can turn upon the pivot 9. An arm
10 of the piece 8 projects towards a small axle 11, of which the two ends are
furnished with a cam 12 and an armature 13. Two electro magnets cased in the
bobbins 14 and 15 are arranged horizontally in face of the armature 13. In the
position indicated at Figures 2 and 4 the armature assumes a vertical position, but
when an electric current is send into the bobbins the electro magnets of the bobbins
attract the armature 13 and turn it to 90° (see Figure 5), which affecting the cam
12 lowers the arm the piece 8 so that the point of the carbon 2 touches the
carbon 1. A spring 16 fixed to the standard 17 which touches the piece 8 tends
to separate the two carbons.
The two terminals 18 and 19, which serve to introduce the two wires coming
from a battery or from an electric generator, are united to the bobbins 14 and 15
and to the carbons 1 and 2 in the following manner:-The terminal 18 conducts
the current at one time by the wire 20, the standard 17, the piece 8, to the
carbon 2, and at the same time by the wire 21 to the bobbins 14 and 15; the
terminal 29 conducts the current by the piece 5 at one time to the carbon 1, and
another time by the wire 22 to the bobbins.
The automatic lighting is made in the following manner:-
-The apparatus is in
the normal position, see Figures 2 and 4, the two carbons separated from one
another, a current, which is sent into the terminals 18 and 19, not being able to.
pass by the carbons takes its course by the wires 21 and 22 to the bobbins; this
turns the armature 13 so that the extremities of the carbons touch. At this
instant the electric current taking the shortest route passes by the carbons which
light up, and the electro magnets of the bobbins 14 and 15 releasing the armature,
in consequence of the interuption of the current, determines the separation of the
carbons, and the current once established between the carbons keeps its direction,
and produces the arc between the two carbons.
I have shown in Figures 6, 7, and 8 a modification of the cam 12, which in the
Figures 4 and 5 being hollow acts by its interior surface upon the arm 10, whilst
in the three first Figures it is solid, so that it is the exterior surface which lowers
the arm 10.
In the modification of the Figure 9 the cam and the armature are suppressed.
The arm 10 of the piece 8 carries at its extremity the armature 23, which, at the
desired moment, is drawn directly by the electro magnet of the bobbin 24, which
makes the two carbons 1 and 2 touch; a regulating screw 25 serves to limit the
stroke of the arm 10.
The two carbons are of any appropriate length, and the feed is made from time
to time by pushing them forward simultaneously by hand in the tubes 3 and 4.
For this purpose I fit to the extremities of the tubes behind the carbons the small
pins 26 and 27, of which each carries a roller 28, 29; a cord 30, fixed to the bearer
7, passes round the rollers and then over the return pulley 31, so that in drawing
the free end of the cord the carbons slide in the tubes 3 and 4, and are fed
simultaneously. I obtain the same result in an automatic manner by suspending a
weight 32 to the cord; the weight is prevented from falling by an eccentric 33,
controlled by a stem 34, crank 35, and a helix in metallic wire 36 placed near the
carbon. When the carbons are consumed so that their incandescent points

page_text: approach the spiral 36 the spiral dilates by the heat, presses against the crank 35,
which releases the eccentric 33, and the weight 32 being no longer held pushes as
it falls the carbons a certain distance forward. Directly the spiral cools, that is to
say, instantly the spring contracts and the eccentric grasps again the cord and the
feed is arrested. This effect is produced at intervals till the carbons are consumed,
when they are replaced by others, or others with their ends turned in the forms of
a mandril and matrix to fit into hollows left in those burning, which can be added
on so as to make them continuous.
Another modification is as follows:-In the ratchet form of the apparatus the
ratchet is worked continuously by means of a portion of the current passing
through an electro magnet or electro magnets in any of the ways well known to
electricians, the apparatus being arrested by the heated or fusible stops, the same
as shown in Figure 10, wherein is shown a plan of a portion of the stop mechanism.
a is the axle of the disc d holding the stops 6 arranged radially, the axle a being
in connection with a train of clockwork or the ratchet form which propels the
carbons; c is the stop arresting the fusible stop b.
b
In Figure 11 is shown in elevation the parts of the mechanism shown in Figure 10,
d being the radial wheel holding the fusible stops b, b; one of the stops b, b, being
shown ready to be fused, burnt, or softened by the heat of the electric arc, the
carbons themselves being shown at e, e; the stop c and the axle a of the radial
wheel are suitably insulated.
Having now described and particularly set forth the nature of the said Invention
and the manner of carrying the same into effect, I would have it understood that
what I claim is,―
1. The pivoting of the lower carbon holder or one of the carbon holders in
the manner described for the purpose of relighting, substantially as set forth.
2. The feed motion without clockwork, substantially as described, by means of
an acting ratchet in combination with the stops, as described, or in combination
with the expanding wire, as described.
3. The fusible stops of metal or other material to be acted on by the heat of the
carbons to put into action the ratchet or other device for bringing forward the
carbons, substantially as described.
4. The general arrangement and construction of the apparatus and mechanism,
substantially as described for the purposes set forth.
5. The employment of a consumable, but not inflammable non-conductor, which
may be loose or attached, placed between the carbons so as to impede the passage
of the current excepting where the arc is formed at the points, substantially as
described.
In witness whereof, I, the said Gustavus Palmer Harding, have hereunto set
my band and seal, this Ninth day of May, in the year of our Lord One
thousand eight hundred and eighty
G. P. HARDING. (L.S.)