IMPROVEMENTS IN ELECTRIC LIGHTING APPARATUS
Year: 1878

page_text: LETTERS PATENT to Peter Jensen, of 33, Chancery Lane, London, for the Inven-
tion of "IMPROVEMENTS IN ELECTRIC LIGHTING APPARATUS." A communica-
tion from abroad by Siegfried Marcus, of Vienna, in the Empire of Austria,
Mechanical Instrument Maker.
Sealed the 21st January 1879, and dated the 10th October 1878.
PROVISIONAL SPECIFICATION left by the said Peter Jensen at the Office
of the Commissioners of Patents on the 10th October 1878.
PETER JENSEN, of 33, Chancery Lane, London. "IMPROVEMENTS IN ELECTRIC
LIGHTING APPARATUS." (A communication from abroad by Siegfried Marcus, of
Vienna, in the Empire of Austria, Mechanical Instrument Makor.)
The object of this Invention is by means of a relatively feoble electric current to
give a small but constant, quiet, and intense light, and to make it possible to produce
by means of a single electric source a considerable number of sinall lights in such a
manner that according to the construction of the apparatus the lights may be
arranged both in one single circuit and in branch lines (starting from the main
circuit).
This apparatus differs mainly from electric lamps and carbon holders hitherto
in use by its not being based upon the principle of breaking the circuit, but on the
contrary being based upon the principle of a closed circuit, so that the light does
not appear as with the other apparatus as a light of the arc system, but by incan-
descence of the carbon. The apparatus may be of whatever size one likes, and
consists essentially of a bed plate or base and a standard with two arms, of which
the lower one is in the electric circuit, and the upper one is insulated therefrom by
a non-conductor. A metallic adjustable carbon holder is fixed in the lower arm,
and carries a carbon cylinder (or truncated couc) which can turn round its axis. If
the apparatus is intended for continuous lighting of long duration the cylinder
axle as well as its brasses may be provided with screw threads, whereby a horizontal
progressive notion may be given to the cylinder contemporary with its rotatory
motion round its axis.
A tube is passed through and fastened to the outer end of the upper arm, and
carries two grooved metal pulleys pressed together by springs. These pulleys may
be replaced by a yielding metallic inouth-piece composed of several parts.

page_text: Between the said pulleys the carbon rod is held, resting or bearing upon the
carbon cylinder under the pressure of a bar passing through the tube, and provided
with a small weight. Where long carbon rods are to be used the bar pushing down
the carbon rod may be replaced by a small pulley mechanism in connection with a
small weight. In that case one of the pulleys holding the carbon rod should be
notched or roughened to move downwards the carbon rod by friction for pressing
the same upon the carbon cylinder. It should be remarked that the direction of
the carbon rod is not tangential to the circumference of the carbon cylinder, but
between the circumference and the centre. There are two binding screws, one in
electric circuit with the standard, the other with the upper arm.
For working this lighting apparatus a current of suitable power is let into the
same, passing through the standard lower arm carbon cylinder, thence through the
carbon rod and the pulleys to the upper arm, and vice versa. The great resistance
the current meets with on its passing from the carbon cylinder (which in consc-
quence of its large cross section facilitates the passage of the current) to the thin
carbon rod causes the latter to become incandescent at the contact, emitting intense
rays, and burning slowly down; but the carbon rod is fed in proportion to its cou-
bustion by the pressure exercised upon the same by the weighted bar, so that the
carbon rod and the carbon cylinder are in permanent contact.
A further consequence of the carbon rod's feeding motion is the revolution of the
carbon cylinder as the carbon rod presses excentrically on the cylinder's circum-
ference (but this revolution may also be facilitated by springs or weights). By this
arrangement the following advantages are obtained-a, the contact between the
surface of the carbon cylinder and the rod is continuously renewed; and, b, no
accumulation of ashes, diminishing the contact and extinguishing the light, can
occur.
As there is no break in the circuit while the carbon rod is incandescent it is
obvious that this kind of lighting apparatus may be arranged in a circuit or in
branch lines.
General advantages of the electric lighting apparatus by incandescence,―
1. Great stability and constancy of light with corresponding intensity of the
same, varying from a lighting power equivalent to one candle up to a large number
of gas lamps.
2. Its principle and construction afford possibility to work a large number of
lights from one single source of electricity.
many
3. The lights may be arranged as well in a single circuit as also in branch
lines, starting from one main circuit, by which reason,-
4. This apparatus is especially suitable for street lighting and in squares, for
large establishments, railway stations (railway trains), factories, theatres, and
museums, as well as for domestic purposes.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Peter Jensen in the Great Seal Patent Office on the 10th April
1879.
PETER JENSEN, of 33, Chancery Lane, London, "IMPROVEMENTS IN ELECTRIC
LIGHTING APPARATUS." (A communication from abroad by Siegfried Marcus, of
Vienna, in the Empire of Austria, Mechanical Instrument Maker.)
The object of this Invention is by means of a relatively feeble electric current to
produce a small but constant, quiet, and intense light, and to make it possible to

page_text: produce by means of a single electric source a considerable number of small lights
in such a manner that according to the construction of the apparatus the lights may
be arranged both in one single circuit and in branch lines (starting from the main
circuit).
The electric lighting apparatus constructed according to this Invention produces
light by incandescence, and is illustrated by the annexed Drawing. Figure 1 is a
side elevation, and Figure 2 an end elevation of the apparatus; Figure 4 is a side
elevation, Figure 5 an end elevation, and Figure 3 a detail of a modification. The
same letters refer to corresponding parts.
This apparatus differs from electric lamps and carbon holders hitherto generally
in use by its not being based upon the principle of breaking the circuit, but, on the
contrary, being based upon the principle of a closed circuit, so that the light does
not appear as with the other apparatus as a light of the voltaic are system, but by
incandescence of the carbon. The apparatus may be of whatever size one likes, and
consists essentially of the bed plate or base A, Figures 1 and 2, the standard B with
its two arms C and D, of which C is in the electric circuit, and the other D is insu-
lated therefrom by a non-conductor Y. The metallic adjustable carbon holder F
is at E fixed in the lower arm, and carries the carhon cylinder (or it might be a
truncated cone) H, which can turn round its axis G.
This apparatus being especially intended or suitable for a continuous lighting of
some duration the cylinder spindle G, as well as its brasses or centre bush, are
shewn provided with fine screw threads, the bush forming the nut for the screw
spindle, whereby a horizontal progressive motion is given to the cylinder H simul-
taneously with its rotatory motion round its axis, thus constantly changing, and
clean points of contact are obtained, and a steady light by incandescence is ensured;
the point of the carbon rod K describes a helical path. A cylindrical tube J is
passed through and fastened to the outer end of the arm D; U, U¹, is a metallic
tongs-shaped clamp; the bar or leg U is screwed on the arni D, and the lever U¹ is
pivotted in the fork T, so that it may turn on the spindle Z. On the ends of these
two pieces the two metal pullics or rollers R and R' are pivotted, being pressed
together by the spiral spring P.
Between the said pullies the carbon rod K is held, resting or bearing upon the
carbon cylinder H under the pressure of the bar N, passing through the guide tube J,
and provided with a small weight L. Where long carbon rods are to be used the
bar N pushing down the carbon rod may be replaced by a small pulley mechanism,
as shewn in Figures 3, 4, and 5. On the axle of the pulley R there is fixed a
second pulley Q, Figures 3 and 5, which is acted on by a small weight L in a cord
passing round the pulley Q. In that case the pulley R, holding the carbon rods,
should be notched or roughened to move downwards the carbon rod by friction for
pressing the same upon the carbon cylinder H. It should be here remarked that
the direction of the carbon rod K is not tangential to the circumference of the
carbon cylinder H, but between the circumference and the centre of the same, as
shewn.
There are two binding screws S and S', the first of which is in electric circuit
with the standard, the second with the upper arm D by meaus of the screw S".
The position of the carbon cylinder H against the carbon rod K may be varied at
will with a slight modification of the mechanism, as for instance the carbon rod K
may, as illustrated in Figures 4 and 5, be arranged under the carbon cylinder H, or
the carbon rod may touch the latter in a horizontal position, or nearly so, without
departing from the leading features of this electric incandescence lighting apparatus.
For working this lighting apparatus a current of suitable power is led into the
same, passing through the standard B, arm C, carbon cylinder H, thence through
the carbon rod K, the pulley R to the arin D, and vice versu.
The great resistance the current meets with on its passing from the carbon
cylinder H (which in consequence of its large cross section facilitates the passage of
the current) to the thin carbon rod K causes the latter to become incandescent at
the contact, emitting, intense rays, and burning slowly down; but the carbon rod

page_text: is fed in proportion to its combustion by the pressure exercised upon the same by
the weighted bar N, so that the carbon rod and the carbon cylinder are in permanent
contact.
As regards the modification shewn in Figures 4 and 5 the suspended weight L
performs the same office as that of the weight L in Figures 1 and 2.
A further consequence of the carbon rod's feeding motion is the revolution of the
carbon cylinder H as the carbon rod presses excentrically on the cylinder's circum-
ference (but this revolution may also be facilitated by springs or weights, in which
case the weight of the bar N is also utilised for the same purpose).. Instead of
giving a continuous axial movement to the carbon cylinder, as here shewn, a
periodical movement may be imparted thereto, say once in every revolution, by
pawl mechanism assisted by a small weight suspended from a pulley on the spindle
on which the cylinder would then be fixed.
By the arrangement herein-before described the following advantages are
obtained(a), the contact between the surface of the carbon cylinder and the rod
is continuously renewed; and (b), no accumulation of ashes, diminishing the contact
and extinguishing the light, can occur. As there is no break in the circuit while
the carbon rod is incandescent it is obvious that this kind of lighting apparatus may
be arranged in a circuit or in branch lines.
General advantages of the electric lighting apparatus by incandescence,―
1. Great stability and constancy of the light, with corresponding intensity of the
same, varying from a lighting power equivalent to one candle up to a large number
of gas lamps.
2. Its principle and construction afford possibility to work a large number of
lights from one single source of electricity.
3. The lights may be arranged as well in a single circuit as also in many branch
lines, starting from one main circuit, by which reason,-
4. This apparatus is especially suitable for street lighting and in squares, for large
establishments, railway stations (railway trains), factories, theatres, and museums,
as well as for domestic purposes.
And having thus described and ascertained the nature of this Invention I declare
that I claim as the Invention communicated to me,-
Firstly. The combination of parts of an electric lamp, namely, a carbon cylinder
free to rotate by the eccentric contact with a weighted or propelled carbon rod held
between rollers or pulleys which are pressed together by a spring, the carbon cylinder
being also axially movable as required, all substantially as described and shewn,
whereby clean and constantly changing points of contact are obtained, and a steady
electric light by incandescence is ensured.
Secondly. The mode or modes of holding the carbon rod by pulley and spring
appliances, substantially as described and shewn.
In witness whereof, I, the said Peter Jensen, have hereunto set my hand and
seal, this Ninth day of April, in the year of our Lord One thousand eight
hundred and seventy-nine.
168
THIYAN