Improvements in Electric Arc Lamps.
Year: 1895

page_text: Date of Application, 5th Jan., 1895
Complete Specification Left, 5th Oct., 1895-Accepted, 9th Nov.. 1895
TRUVIDIONAL
Improvements in Electric Arc Lamps.
We JAMES EGLINTON ANDERSON GWYNNE of Brooke Street Works Holborn
in the County of London Civil Engineer and RANKIN KENNEDY of Clifton Villas
Camden Square Camden Town in the County of Middlesex, Electrical Engineer,
do hereby declare the nature of this invention to be as follows:-
:-
This invention relates to electric arc lamps of the double carbon type and the
object thereof is to effect the transfer of the current from one pair of carbons to
the other and to maintain one pair of carbons out of circuit until the other pair is
consumed by electrical action only without the aid of the mechanical contrivances
Dow in use for this purpose.
Now according to this invention when applied to electric are lamps regulated
on the "Pilsen" system we duplicate the parts and form two complete regulating
mechanisms by combining two shunt and two series solenoids with their respective
cores and carbon holders in one lamp.
We connect the two series solenoids in series with each other and we connect the
two pairs of carbons in parallel' or multiple are by a forked or bifurcated connection
from the end of the said series solenoids.
The current flowing through the two series solenoids pulls up both their cores in
order to strike both arcs but as the two arcs are invariably unequal the current
passes only through the arc of least resistance leaving the other pair of carbons
separated and out of action until the pair of carbons between which the arc of
least resistance was established are consumed. The pair of carbons between which
the arc is first established burn away until the travel of the regulating mechanism
is arrested at a certain point at which the carbons are too short to burn further
the arc then burns open. and its resistance increases until it exceeds that of the
path between the second pair of carbons when the increase of resistance of the said
arc increases the amount of current passing through the shunt solenoids brings the
second pair of carbons together and strikes the arc between them.
By means of the improvements herein before specified we are enabled to construct
an arc lamp that will give a light for from fifteen to twenty hours, such lamps
being very suitable for building and manufacturing operations which have to be
carried on during the night as there is no need to stop the work while the lamps
are supplied with new carbons as is frequently the case with single carbon lamps
which have to burn for lengthened periods of time.
As a modification of our invention we may connect the series solenoids of two
independent single carbon. lamps in the manner herein before described so that when
one lamp is burnt out or accidentally extinguished the other will immediately be
lighted.
This invention is also applicable to other electric are lamps regulated by two
main and shunt coils or magnets.
To insure one pair of carbons being put into action before the other we may
make the series solenoid of that pair of carbons which we desire to be lighted first
with a few less turns of wire than the other or the shunt solenoid may have more
turns of wire.
Or the one carbon holder may be slightly heavier than the other.
Dated this 5th day of January 1895.
בדובד

page_text: Improvements in Electric Arc Lamps.
We JAMES EGLINTON ANDERSON GWYNNE of Brooke Street Works Holborn
in the City of London Civil Engineer and RANKIN KENNEDY late of 1 Clifton
Villas Cumberland Square Camden Town but now of The Phoenix Dynamo
Works Hubert Street Bradford in the County of York Electrician, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
This invention relates to electric arc lamps of double carbon type and the object
thereof is to effect the transfer of the current from one pair of carbons to the other
and to maintain one pair of carbons out of circuit until the other pair is consumed
by electrical action only without the aid of the mechanical contrivances now in use
for the purpose.
Now according to this invention when applied to electric arc lamps regulated on
the "Pilsen" system we duplicate the parts and form two complete regulating
mechanisms by combining two shunt and two series solenoids with their respective
cores and carbon holders in one lamp. We connect the two series solenoids in
series with each other and we connect the two pairs of carbons in parallel or
multiple arc by a forked or bi-furcated connection from the end of the said series
solenoids. The current flowing through the two series solenoids pulls up both
their cores in order to strike both arcs but as the two arcs are invariably unequal
the current passes only through the arc of least resistance leaving the other pair of
carbons separated and out of action until the pair of carbons between which the
are of least resistance was established are consumed or until a greater resistance
arises in the burning lamp. The pair of carbons between which the arc is first
established burn away until the travel of the regulating mechanism is arrested at
a certain point at which the carbons are too short to burn further the are then
burns open and its resistance increases when the increase of resistance of the said
arc increases the amount of current passing through the shunt solenoid of the
second pair of carbons brings the said second pair of carbons together and strikes
the arc between them.
By means of the improvements hereinbefore specified we are enabled to
construct an arc lamp that will give a light for from fifteen to thirty hours or
longer such lamps being very suitable for railway stations street lighting, building
and manufacturing and other operations which have to be carried on during the
night as there is no need to stop the work while the lamps are supplied with new
carbons as is frequently the case with single carbon lamps which have to burn for
lengthened periods of time.
To insure one pair of carbons being put into action before the other we may
make the series solenoids of that pair of carbons which we desire to be lighted first
with a few less turns of wire than the other or the shunt solenoid may have more
turns of wire or the one carbon holder may be slightly heavier than the other.
And in order that our said invention may be fully understood we will proceed
to explain the same with reference to the accompanying sheet of drawings in
which :-
Fig. 1 represents an electric arc lamp regulated on the "Pilsen" system
constructed according to this invention.
Fig. 2. is side view of same.
Fig. 3. is plan of same.
The same letters denote the same parts in all the figs.
The lamp shewn consists of two "Pilsen" regulating mechanisms side by side

page_text: connected and combined in the manner now to be described.
a a are series
selenoids the shunt solenoids cc¹ the upper carbon holders attached to the
series cores d d'. ff are the lower carbon holders attached to the shunt cores g g'
by means of rods. The two solenoids a a' are in series with the current
entering the lamp and with each other and the shunt coils are in parallel or.
miltiple arc.
The current enters the lamp at the terminal i passes round the coils a a¹ and
thence by wire s to the binding screw k.
From the binding screw k are led two wires or cables l. m. to the cores d' of
the series solenoids so that the current passes from k to the upper carbon holder of
whichever pair of carbons is burning thence across the arc to the lower carbon
older and through the shunt core to the negative terminal of the lamp by wires t.
To ensure one pair of carbons being lighted before the other and to prevent both
pairs of carbons burning together one of the series solenoids say a has more turns
of wire on it than a' in which case the magnetic pull of the solenoid a on its core d
will be greater than the pull of solenoid a¹ on its core di consequently the carbons
actuated by solenoids a and b will be more widely separated than the carbons
actuated by solenoids a¹ and b' and the arc (when the current is switched on) will
be struck between the pair of carbons actuated by solenoids a¹ and b' which
carbons will burn until their carbon holders have come as close together as the
construction of the lamp will admit.
The arc then burns open until the increase of resistance of the are causes more
current to pass through solenoid b and brings the carbons actuated by solenoids a
and together and strikes the arc between them.
This latter pair of carbons then burn until exhausted or until the lamp is
extinguished.
A lamp constructed as hereinbefore described will give a light for from fifteen
to thirty hours or more without attention the change over from one pair of carbons
to the other being automatic.
Instead of the series solenoids being wound with different amounts of wire the
shunt solenoids may be wound with different amounts of wire or the carbon
holders or cores or both of one pair of solenoids may be heavier than the other.
As a modification of our invention instead of using two pairs of carbons in
one lamp we may use two independent lamps having one pair of carbons each
and connect the said lamps in the manner herein before described that is to say
with the series solenoids in series and the carbons in multiple are so that when
one lamp is burnt out or accidently extinguished the other will immediately be
lighted.
This invention is also applicable to other electric are lamps regulated by two
series and shunt solenoids or magnets.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In electric arc lamps regulating two pairs of carbons in one lamp or otherwise
by means of two solenoids connected in series and two shunt solenoids connected in
multiple arc the carbons being connected in multiple arc by means of a forked or
bifurcated connection from the end of the series solenoids substantially as herein-
before specified and for the purpose stated.
2. In electric arc lamps the combination of two solenoids connected in series
with two pairs of carbons connected in multiple arc by means of a bifurcated
connection from the said solenoids and the means of ensuring one pair of carbons
only burning at one time substantially as hereinbefore specified.
3. In electric are lamps regulated on the "Pilsen" system the combination in
one lamp of two "Pilsen" regulating mechanisms with their carbon holders the
series solenoids of the said mechanisms being connected to each other in series and
:

page_text: the shunt solenoids connected to each other in multiple are the carbon holders
being also connected in multiple arc substantially as herein before specified.
4. An electric arc lamp having two pairs of carbons regulated by two. series and
two shunt solenoids whereof the series solenoids are connected together in series
and the shunt solenoids in multiple arc, the two pairs of carbons being connected
together in multiple arc by means of a bifurcated connection from the series
solenoids all substantially as herein before, specified and, shewn by the accompanying
drawings.
5. The modification of this invention as applied to separate and independent
Jamps substantially as herein before specified.
6. The improved construction of electric arc lamps substantially as hereinbefore.
described and shewn by the accompanying drawings.
Dated this 5th day of October 1895.
T. E. HALFORD,
11 Furnival Street, Holborn, E.C., Agent for Applicants.