IMPROVEMENTS IN OR CONNECTED WITH ELECTRIC LAMPS
Year: 1882

page_text: LETTERS PATENT to William James Mackenzie, of Glasgow, in the County of
Lanark, North Britain, for an Invention of "IMPROVEMENTS IN OR CONNECTED
WITH ELECTRIC LAMPS."
PROVISIONAL SPECIFICATION left by the said William James Mackenzie at
the Office of the Commissioners of Patents on the 7th January 1882.
WILLIAM JAMES MACKENZIE, of Glasgow, in the County of Lanark, North-
Britain. "IMPROVEMENTS IN OR CONNECTED WITH ELECTRIC LAMPS."
This Invention relates to improvements in or connected with electric arc lamps
which consist (firstly) in special means whereby the feeding of the carbon pencils
or electrodes is controlled, and their resistance minimised; and (secondly) in novel
arrangements of regulating appliances connected with electric arc lamps, to be
used either in combination with or separately from the first part of the improve-
ments, whereby more perfect regulation of the distance between the electrodes may
be secured for the purpose of maintaining the arc steadily.
In carrying out the first part of the Invention, I support or carry the carbon
pencils at their ends in the usual way, but I also support them at the points where
they assume the form of rounded cones by means of pointed pieces of conducting
or of non-conducting and not readily fusible material, such as agate, or iron, or
platinum, fitted against the pencils at points equidistant round the circumference,
and at that part of each pencil where it has passed from the cylindrical, and assumed
the conoidal form. These supporting points are fixed by preference on rings
surrounding the pencils, and connected to a sliding or movable carrier acted on by
means of regulating appliances, and as the electric currents may be directed through
these rings or pointed holders, the resistance due to the length of the carbons
through which the current usually passes, is reduced to a minimum. I feed or urge
forward the pencils, through the supporting ring or pointed holders by means of
weights or springs, so that as the points of the pencils waste away by the action
of the current, they are continually replaced by fresh portions of the carbon; and
the points of the carbon pencils protrude through the ring holders to an extent
Price 6d1

page_text: which remains constant, or only varios in a minute degree. The pencils, after the
current commences to flow through them, are soparated to the requisito distance
for maintaining the arc, by means of any ordinary electro-magnetic arrangement
excited and actuated by the current itself, or by means of the improved arrange-
ment hereinafter described, acting on the sliding carrier to which the ring and
supporting pieces are connected.
When carbon pencils of large diameters are used, or arcs of considerable length
are formed, it may in general be unnecessary to provide any further means of
regulation than the pointed holders for maintaining the arc; but when small
diameters of pencils are used, or arcs of short length formed, slight irregularities
in the wasting of tho pencils are overcome by the ordinary electro-magnetic
arrangements referred to, acting through levers on one of the rings or pointed
pencil holders, or by means of the improved arrangement in which the second part
of my Invention consists. This novel regulating arrangement, which may be also
applied to are lights or lamps, to which the improved feeding appliances are not
fitted, comprises a small electro-motor which is caused to rotate in one direction
or the other by a battery, the currents from which are directed through the
positive or negative terminals of the motor coils by means of a relay arrangement,
such as is used in connection with telegraph instruments, and which is acted on by
the electric arc current. The electro-motor is connected either direct or through
gearing to the carrier of one of the pointed pencil holders, and as the motor rotates
in one direction or other, the pencil holders are thus caused to approach to or
recede from one another.
In some cases I replace the negative pencil and pencil holder by a block of
carbon or other conducting material.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William James Mackenzie in the Great Seal Patent Oflice on
the 5th July 1882.
WILLIAM JAMES MACKENZIE, of Glasgow, in the County of Lanark, North-
Britain. "IMPROVEMENTS IN OR CONNECTED WITH ELECTRIC LAMPS."
My said Invention relates to improvements in or connected with electric arc
lamps which consist (firstly) in special means whereby the feeding of the carbon
pencils or electrodes is controlled, and their resistance minimised; and (secondly)
in novel arrangements of regulating appliances connected with electric arc lamps
to be used either in combination with, or separately from the first part of tho
improvements, whereby more perfect regulation of the distance between the
electrodes may be secured, for the purpose of maintaining the arc steadily.
In carrying out the first part of the Invention, support or carry the carbon
pencils at their ends in the usual way, but I also support them at the points where
thoy assume the form of rounded cones by means of pointed pieces of conducting
or of non-conducting and not readily fusible material, such as agate, or iron, or
platinum, fitted against the pencils at points equi-distant round the circumference,
and at that part of each pencil where it has passed from the cylindrical and
assumed the conoidal form. These supporting points are fixed by preference on
rings surrounding the pencils, and connected to a sliding or movable carrier acted
on by means of the regulating appliances; and as the electric currents may be
directed through these rings or pointed holders, the resistance due to the length
of the carbons through which the current usually passes, is reduced to a minimum.
I feed or urge forward the pencils through the supporting ring or pointed holders,
by means of weights or springs, so that, as the points of the pencils waste away
by the action of the current, they are continually replaced by fresh portions of the
carbon. The points of the carbon pencils protrude through the ring holders to an
extent which remains constant, or only varies in a minute degree. The pencils,
after the current commences to flow through them, are separated to the requisite
distance for maintaining the arc, by means of any ordinary electro-magnetic
arrangement, excited and actuated by the current itself, or by means of the
improved arrangement hereinafter described, acting on the sliding carrier to which
the ring and supporting pieces are connected.
When carbon pencils of large diameters are used, or ares of considerable length
are formed, it may in general be unnecessary to provide any further means of
regulation than the pointed holders for maintaining the are; but when small
diameters of pencils are used, or arcs of short length formed, slight irregularities in
the wasting of the pencils are overcome by the ordinary electro-magnetic arrange-
ments referred to, acting through levers on one of the rings or pointed pencil
holders, or by means of the improved arrangement in which the second part of
my Invention consists. This novel regulating arrangement which may be also
applied to arc lights or lamps to which the improved feeding appliances are not
fitted, comprises a small electro-motor which is caused to rotate in one direction
or the other, by a part of the current used to produce the light, or by a battery,
the currents from which are directed through the positive or negative terminals
of the inotor coils by means of a relay arrangement, such as is used in connection
with telegraph instruments, and which is acted on by the electric are currents.
The electric motor is connected either direct or through gearing to the carrier of

page_text: one of the pointed pencil holders, and as the notor rotates in one direction or
other, the pencil holders are thus caused to approach to or recede from one another.
In some cases I replace the negative pencil and pencil holder by a block of carbon
or other conducting material.
In order that my said Invention, and the manner of performning the same may
be properly understood, I have hereunto appended a Sheet of explanatory Drawings
representing various modifications of my improved arrangements of regulators for
arc lights.
In these Drawings, Figure 1 is a sectional side elevation, and Figure 2 is a
transverse vertical section of an arc lamp of my improved construction, in which
the carbon pencils are placed horizontally. Figure 3 is an enlarged view, partly
in section, of the carbon holders for the same lamp; Figures 4 and 5 are end views
of the fixed and movable holders respectively. Figures 6 and 8 are side elevations
and Figure 7 a plan, showing modifications of my improved regulators for arc
lamps. In the are lamp represented in Figures 1 to 5, the carbon pencils A A',
are fixed in long tubes B, B', the tube B holding the positive carbon A being
stationary and held by brackets c forming part of the framing C of the lamp, while
the tube B, holding the negative carbon A¹ is fitted movably by being suspended
by links el jointed to it and to the framing. The carbon rods or pencils A A' are
held and supported at their outer ends by the metal piston holders sliding in
the tubes B, B. These pistons b, b, are urged forward by the springs D, D, and
carry before them the carbon pencils A, A These pencils are also supported at
their inner extremities each by the three points e, e, e, e¹, e, c', which in this
example consist of iron or steel studs screwed into small brackets e, formed on or
fixed to rings E on the brackets or links c, c¹, and which are ranged equidistant
around the circumference of the carbons. The supports e of the one carbon are
fitted intermediately between the supports e' of the other, to enable them to
approach sufficiently close. These supporting points e el are set to hold the
carbons A, A, at the parts which are worn to the conoidal form by the passing
of the electric current, and to a great extent regulate the length of arc; but as
a means of regulating the arc, the movable tube or holder B¹ is free to move to a
slight extent horizontally, when an armature f on one of the links c' is acted on
by electro-magnet F fixed to the framing C. This electro-magnet F is opposed
by a spring G acting through the curved lever H on a continuation of the link c'.
Wires I and I connected to a dynamo or other electric generator are attached
to the bracket c and link e' or other parts of the positive and negative carbon
holders, and the current entering the positive wire I* flows to the supporting
ring E, and by the points e e e, of the one holder, to the carbon pencil A. It then
crosses over to the other holder by the protruding carbon points, from the second
holder it flows by the links c', and a connecting wire i, to and through the electro-
magnet F, and thence out by the negative wire 1-. When the current commences
to flow, the elect: o-magnet Fattracts the armature f on the movable link c', and
the carbon A, is drawn away from the carbon A, and remains at a distance
suitable for maintaining the arc, this distance being regulated by the tension of
the spring G. The lever H is so curved that when the armature f approaches the
electro-magnet F, and the attraction of the latter increases, the leverage of the
spring G is proportionately increased. As the carbon points waste away fresh
portions are pushed forward by the springs D, and if the carbon points should
waste or slip forward irregularly, this action is automatically corrected by the
mutual action of the electro-magnet F, spring G and lever H.
In the arrangement of regulators shown in Figures 6, 7, and 8, an electro-
motor J is operated by the current distributed through a relay arrangement, to
turn a screw fitted in one of the carbon holders and moving it towards or from
the other carbon holder, as the carbon wastes away; and thus to steadily maintain
Any motor whose field magnets are electro-magnets may be employed for
this purpose.
the arc.

page_text: In the arrangement shown in Figure 6, a wire I* from the electric generator is
connected to the field magnets J of the motor, and thence a wire I is connected to
the movable holder B₁ of one of the carbons. When the carbons are touching or
the arc is maintained the current passes through the carbons A¹ A to the other
holder B, to which a wire 13 is attached and connected to an electro-magnet F, and
thence the current passes out by a wire I-. The electro-magnet F acts on an
alternating current relay arrangement. This relay comprises a central and two
outer contact stops and 1,, between which hang contact pieces k, k¹ formed or
fitted on the end of an oscillating lever K carrying the armature which is
attracted by the electro-magnet F. The attraction of the electro-magnet F is
opposed by a curved lever H and spring G as in the modification shown in Figure 1.
The relay stops and are connected by wires I, 15, to the commutator
brushes j, j, of the armature J' of the motor J. A wire I connects the field
magnets of the motor J to the contact piece k and a wire 17 connects the contact
piece to the wire I-. When the relay stops are held interinediately
between the relay points and ', as is the case when the arc is maintained and
the power of the electro-magnet F and that of the spring G balance each other,
the current flows by the wire I* through the field magnets J of the motor, and
through the carbons A', A and the electro-magnet F to the wire I- without acting
on the motor. But if the arc is lengthened or broken the electro magnet F ceases
to attract the armature f, and the spring G by acting on the lever K, brings the
pieces,, into contact with the relay stops 1, l', so that the contact piece k
touches the stop L, and the piece touches one of the stops ', and part of the
current is shunted through the wires I* 15 to the armnature J of the motor,
whereby the motor is rotated in one direction, and the screw m which may be
connected to the motor shaft direct or through gearing, is caused to turn in a screw
nut m¹ fitted in the end of the carbon holder B. The carbons are by this means
brought closer together until the arc is of proper length or again formed, when the
current by flowing through the electro-magnet F causes the armaturo f to be
attracted, and the pieces are drawn out of contact with the relay stops l l.
If on the other hand, the carbons A. A' are too close, or in contact, the current
flowing through them and through the electro-magnet F being more powerful
causes the electro-magnet to attract the armature f, and bring the point into
contact with the relay stop l, and the piece k into contact with one of the stops ¹
by which means the current through the armature of the motor is reversed, and the
motor rotates in the opposite direction also turning the screw m to draw the
carbons apart.
The connections are thus so managed that the relay shunts part of
the current through the armature of the motor in one direction or other, according
as it is in contact with the right or left hand stops. The field magnet coils J form
a continuous path for the current, carrying the whole of it when the relay makes
contact with neither stop. In this arrangement the lower carbon is fixed and the
upper one is fed by the action of the motor J turning the screw m in the nut m' of
its holder, which is fitted to slide in a guide M in the framing carrying the parts
of the lamp. The means of regulating shown in the plan Figure 7, is substantially
the same as that shown in Figure 6, but the carbons not being seen, the connecting
wires thereto are also left out. The arrangement will be readily understood from
the use of the same reference letters to indicate like parts in these Figures.
The arrangement of regulator applied to the lamp shown in Figure 8, differs
from those shown in Figures 6 and 7, in so far as the relay acts by short circuiting
the motor instead of by reversing the current to the armature of the motor, and
also in so far as the lower carbon is also made movable within certain limits. The
current when it commences to flow passes into the motor by the wire I*, and by
the wire to the carbon holders B, B₁, thence by the wire Is to the electro-
magnet F, but instead of passing out direct by the wire I-, it flows thence by a
wire 13 to an electro-magnet N, and by a wire 1° connecting this magnet to the
wire I The lower carbon holder is held up to keep the carbons in contact

page_text: at the time of starting the lamp, by means of a spring O bearing on part of the
lamp framing M, and against a soft iron block or arinature P just over the electro-
magnet N. When the current commences to flow, the electro-magnet N attracts
the soft iron block P, against the power of the spring O, and thereby depresses the
carbon holder B, and carbon A to form the arc. At the same time the electro-
magnet F attracts the armature f, and brings the contact piece in contact with
the relay stop l, and the motor is at once short circuited. The current now flows
from the wire I* to the wire 110 through the swinging lever K and by the piece
to the relay stop l, thence by the wire 11 to the wire I, by which the current is
carried through the carbons so long as the arc is maintained. If the arc is broken
by the wasting of the carbons, the electro-magnet N ceases to act, and the spring O
raises the lower carbon holder. A spring contact piece p on the armature P
connects the relay stop l, and the terminal of the wire I-. The electro-magnet F
owing to the stoppage of the current through it at the same time ceases to attract
the armature and the points kl, are drawn by the spring G out of contact.
The current cannot then flow direct to and through the carbons by the wire 12, but
flows through the motor J, and by the wire I² and relay stop and contact piece p
to the negative wire I, thereby rotating the motor and through the screw m and
nut m feeding down the upper carbon, until the arc is formed, when the electro-
magnet attracts its armature, and the current flows as before direct to and
through the carbons, the armature P being at the same time attracted by its electro-
magnet N to separate the carbons and maintain the arc. The springs G and O are
so adjusted in relation to the strength of the electro-magnets F and N that their
action in causing contact or separation of the contact pieces kl and plis only
momentary, and in practice it results that the motor J is actuated to rotate the
screw m within the nut m¹ continuously in one direction, to feed the carbon A¹ as
it wastes away.
Having thus described my said Invention and the manner of performing the
same, I have to state that I do not restrict myself to the precise details herein
described or delineated, but what I consider to be novel and original and therefore
claim as the Invention secured to me by the herein before in part recited Letters
Patent is
--
First. The arranging and combining of the parts of electric are lamps, and of
regulators for are lamps substantially in the improved manner herein described
with reference to the accompanying Drawings.
Second. As a means of partial or complete regulation in electric arc lamps, the
fitting of the carbon holders with three or more points or gripping pieces (e, c',) to
grip or hold each carbon electrode at the conoidal ends, substantially as herein
described in reference to Figures 1 to 5 of the accompanying Drawings.
Third. In electric arc lamps, the fitting on the carbon holders, of the gripping
points or pieces (e, e¹,) to serve as a partial means of regulation, in combination
with the improved means herein described of regulating and maintaining the arc,
by the action of an electro-magnet and spring lever, or by the action of a relay
and electro-motor.
Fourth. The combining with an electric are lamp of a relay arrangement and
electro-motor, as a means of regulating and maintaining the are, substantially as
herein described, in reference to Figures 6, 7, or S, of the accompanying Drawings.
Fifth. As a means of regulating and maintaining the are in electric lamps or
lights, the fitting of an electro-motor to turn a screw direct or through gearing
and bring together or separate the carbon electrodes, or to feed forward the one
electrode, such motor being actuated by an electric current directed through relay
arrangements of the kind herein described in reference to Figures 6, 7, or 8 of the
accompanying Drawings.
Sixth. In electric are lamps or lights the arrangement of an electro-magnet (N)
and opposing spring (0) to actuate the one electrode and form the are, in combina-
tion with the arrangement of relay and electr -motor for feeding forward the

page_text: other electrode to regulate and maintain the are, substantially as herein described
in reference to Figure 8 of the accompanying Drawings.
In witness whereof, I the said William James Mackenzie, have hereunto set
my hand and seal this Twenty sixth day of May, in the year of our Lord,
One thousand, eight hundred and eighty two.
Witness,
WALLACE FAIRWEATHER C.E.
Of W. R. M. Thomson & Co.,
Patent Agents,
Glasgow.
W. JAB. MACKENZIE. (L.S.)