IMPROVEMENTS IN ELECTRIC LAMPS AND FITTINGS THEREFOR"
Year: 1883

page_text: "
LETTERS PATENT to John Grice Statter of Snapethorpe near Wakefield, in
the county of York for an Invention of IMPROVEMENTS IN ELECTRIC
LAMPS AND FITTINGS THEREFOR"
"
86
PROVISIONAL SPECIFICATION left by the said John Grice Statter at the
Office of the Commissioners of Patents on the 8th March 1883.
-
JOHN GRICE STATTER of Snapethorpe near Wakefield in the county of York
IMPROVEMENTS IN ELECTRIC LAMPS AND FITTINGS THEREFOR
My invention relates to improvements in electric lamps and fittings therefor the
object of my invention being to ensure in a better manner than hitherto the
gradual feeding of the carbons in arc lamps as they are consumed without serious
intermittence or irregularity, to allow, the lamp to be automatically cut out of
circuit when the carbons are consumed or become fixed, and to allow of extinguishing
any lamp or lamps out of a number without interrupting the main current; the
improvements also relate to an improved carbon holder for arc lamps, and to
improvements in adapting existing gas fittings for electric light fittings, and to an
improved holder for incandescent lamps.
In carrying out the first part of my invention I effect the regular feeding
of the carbons in electric lamps by means of the feed current in the following
manner.
The lower carbon holder is usually fixed, though not necessarily so, and the upper
one is constructed of a brass or other metal rack and descends upon the lower
holder by its own gravitation. The teeth of the rack engage with those of a
pinion fixed as hereinafter described upon a light spindle and upon this spindle
the armature of a dynamo electric motor, or an iron rimmed wheel under magnetic
control revolves.
The chief parts of the mechanism are supported by two side plates which connect
the, upper and lower plates of the lamp. and. are screwed or otherwise firmly fixed
to them. Between these side plates revolves an armature of suitable construction
mounted on a spindle carrying a commutator and pinion and surrounding the
Price 8d1

page_text: E
armature is an electro magnet with curved pole pieces. The magnet is supported
directly from the base plate by brass plates, and is wound with thick wire.
A suitable construction of armature consists of a number of thin curved iron
plates which are arranged edge to edge to form a ring, a depression is cut in the
middle of each plate which when they are arranged in order, formis a groove down
the centre of the outer surface and in this groove soft iron wire is laid and
soldered down leaving however the two ends free, two wires are similarly soldered,
one round each outside edge their ends being left free also; the ring can now be
stretched out flat, put into a lathe and wound, after winding it is bent up, the end
wires (used to hold it in the lathe) being then cut so as to form a dowel which
ensures good contact for the two ends.
In the winding-process each of the iron plates has wound upon it a distinct coil
and when cramped to the ring shape these coils meet internally but leave spaces
between one another on the outer surface.
The coils are connected up to the commutator in the same manner as the
Paceinotti coils.
000
The commutator consists of a number (the same as the number of coils) of
radial brass strips insulated from one another, and is pressed upon by brushes
kept in contact by springs. The pinion is fixed upon the shaft so that the shaft
and armature can rotate through a few degrees before lifting the rack with whose
teeth the pinion engages.... This is effected by fixing, firmly to the shaft a, collar
having in it a groove into which projects a pin, which is driven or s
screwed into
the pinion and before the current passes the pin is kept in position by the tension
of a spring.
When the current passes, the direction of rotation is such that the motor moves
until the pin catches the opposite side of the groove thereby extending the spring
before the weight of the rack is taken by it.
On the outer side of one of the side plates but contained within the casing is an
arrangement for short circuiting for an instant the dynamo-electric motor
This arrangement consists of two solenoids (one of coarse and 'one of fine wire)
resting on a brass plate and having armatures respectively attached to opposite
ends of a balance arm and mounted on guide rods passing through the brass, plate.
The balance arm, carries a pointer steadied, by springs whose tension, can be
regulated by a set screw; opposite the extreme end of the pointer is a screw
supported on an insulated bracket.. Thus when one armature is sucked downwards
and the other rises, the pointer makes contact with the screw.
I will now describe the electrical connections and the action of the lamp, the
current enters by the positive terminal, traverses the electro magnet of the inotor
through one brush to the armature and thence by the other brush to the coarse
wire solenoid after traversing which it arrives at the framework of the lamp, by
which it is given to the rack by the pinion and guides; it now passes through
the arc and returns by the lower carbon holder and wire or strip of metal to the
negative terminal.
"
Another thick wire hereafter designated "the short circuiting wire" starts from
the positive terminal and makes, a helix designated the short circuiting helix
round the coarse wire solenoid and is then attached to an insulated bracket. The
short circuiting wire, and helix, is composed of very-thick wire so as to have less
resistance than the other passage for the current. Hence when the pointer is in
its normal position no current can pass by this short circuiting wire, but when the
pointer makes contact with, the screw. the current can then pass from the bracket
to the screw thence by the pointer and its springs and bearings to the casing.
Thus when the pointer is in contact with its screw the greater part of the current
passes by this short circuiting wire and helix and the armature and the electro
magnet partially lose their magnetism..
3
There is also another passage for, the current which is always open, that is by
the fine: wire solenoid, this has a very high resistance so that only a very small
M

page_text: proportion of the whole current varying directly with the resistance of the are
passes through it.
The action of the lamp is as follows:-First, as regards the motor. The current
passing through the motor tends to turn the armature thereof in such a direction
as to raise the upper carbon holder the power being mechanically transmitted by
the rack and pinion. The force tending to bring the carbon holders; with their
carbons, together is constant as it is produced by the weight of the upper carbon
holder and the force tending to separate them is that produced by the motor and
depends upon the strength of the current passing through the motor which is the
same as that of the current passing through the arc.
The maximum strength of the current passes when the carbons are in contact,
as they are when the current is turned on, the motor then starts and moves round
by itself until the pin catches the side of the niche in the collar, it has then
sufficient power to raise the upper carbon holder and to thereby establish the arc:
This introduces the resistance of the arc and the current passing through the motor
is thereby weakened, but the power of the motor is still sufficient to hold the
upper carbon and holder though not sufficient to raise them any further.
By these improvements a constant equilibrium is produced and will always be
ascertained so long as the current remains steady and the arc will remain at an
approximately fixed length whatever variation may take place in the length of the
carbons owing to their consumption. Thus if by the consumption of the carbons
the are would be made for a moment slightly longer, the motor would no longer
have the power to support the upper holder, which consequently descends until the
original length is reached. This action is always going on, the armature being
extremely sensitive to the decrease or increase of current, because the current
not only passes through the armature but through the electro-magnets which
surround it.
=
If the strength of the current be increased the. length of the arc would also be.
increased' but this is obviated by the herein before described balance arrangement
which also allows many lamps to be burned on the same circuit without interfering
with one another's regulation.
+
As herein before stated the same current which flows through the motor and
are also flows round the coarse wire solenoid thereby attracting its armature.
But this attraction is balanced by the attraction exerted by the fine wire solenoid
on its armature, any slight error being adjusted by the springs. If now the are
becomes slightly longer and the motor fails to regulate quickly, more current passes,
through the shunt coil and less through the coarse wire solenoid (owing to the
increased resistance in this path) the equilibrium is destroyed; the shunt solenoid.
sucks in its armature and the other armature rises. The pointer makes contact
with its screw and the greater part of the current now passes by the short
circuiting wire, the motor is enfeebled and a feed takes place. But the pointer in
the very action of touching its screw brings. the current round the short
circuiting helix, which becomes a strong magnet attracting its armature while
owing to the feed and the additional passage of the current through the, lamp
offered by the, short circuiting wire the shunt coil is not so strongly excited and,
the attraction for the armature diminishes. Thus no sooner has the pointer made
contact with its screw than it leaves it and returns to its old position. If now the
very small feed which has taken place is sufficient to restore the equilibrium,
between the solenoids no further action takes place, but if not the action is repeated.
again and again until equilibrium is restored.
In a modification of the herein before described arrangement I dispense with the
continuous current type of dynamo-motor, the motor arrangement being used,
only to strike the are, the regulation being left entirely to the make and break
balance described in connection with the dynamo motor.
In this modification a pinion is firmly keyed onto a shaft on which is mounted a
light brass wheel surrounded by a broad iron rim.
Above this wheel is an electro-magnet supported in bearings which admit of a)
i

page_text: -
:
swinging motion in a direction parallel to the plane of that of the wheel. The core
of the magnet is continued downwards and an iron shoe is jointed to it so that it is
also capable of a movement in the same plane, or parallel to the plane of the wheel.
When the lamp is not working this shoe fits the iron circumference of the wheel
but is prevented from adhering too closely by a brass piston. which is forced upon
the iron rim by a spiral spring contained in a cylinder which is capable of
adjustment by screwing upwards or downwards.
An alternate method is to fit the shoe with a pawl at its extremity and screw
down the cylinder so that the pawl can only engage with the rim, which is then
made in the form of an iron ratchet wheel, when the magnetic attraction between
the shoe and the rim overcomes the action of the spring piston.
The core of the magnet projects at its upper extremity in a direction parallel to
the plane of the wheel, the projection being preferably a separate piece of iron,
bolted onto the top of the magnet's core; under this projection is an adjustable
block of iron, and outside the side plate is the make and break motor arrangement
exactly as herein before described.
The current enters by the positive terminal, traverses the electro-magnet coils
and passes thence through the bobbin to the framework; from the framework it is
given to the rack by the pinion and guides. The other connections are similar to
those herein before described, viz, another path is open to the current through the
short circuiting wire and helix when the pointer makes contact with its screw but
this is only instantaneous 'since the contact is instantly broken by the passage of
the current through the short circuiting helix, also there is the shunt coil of high
resistance always offering a passage for the current,
Instead of employing one motor I sometimes provide the lamp with two motors.
In this case the armatures of both the motors are placed on shafts connected by
gearing and when the current passes they tend to turn in opposite directions one
against the other; the current is supplied to one of the motors in a similar manner
to that herein before described and tends to separate the carbons, while the other is
in a shunt circuit to the arc and turns in such a manner as to tend to bring the
carbons together. This shunt circuit has considerable resistance introduced so that
the current passing through it shall be weak.
By this arrangement a fixed length of arc will be ensured whatever be the
strength of the current sent through the lamp as equilibrium will exist between the
two opposing motors only when a certain fixed proportion of the current is passing
through each and the magnitude of the whole current is immaterial since so long
as the are remains at this fixed length, the proportions of current and therefore the
relative strengths of the motors remain the same. Hence with any strength of
current the length of the are remains constant provided the current be strong
enough to maintain the arc.
For a focussing lamp the lower carbon holder is not rigidly fixed but is
constructed of a brass or other metal rack working in guides. The shaft carrying
the holders is continued through a bearing and receives a pinion half the size of
the pinion of the upper carbon holder; the teeth of the lower carbon holder rack
engage with those of this pinion but on the opposite side of the shaft to that on
which the upper carbon holder works.
Instead of the said pinion a grooved gripping wheel of the same size may be
employed, and pressed into this grooved wheel by another similar grooved wheel
supported by springs is the carbon itself, guided by fixed guide wheels or smooth
round holes, without any upper holder at all.
My improved holder for electric lamps is constructed of a hollow cylinder
consisting of two parts which screw together, the inside ends of each of these parts
are conical, but are bored through to fit the carbons loosely.
Within the cylinder and held in position by pins running easily in drill holes, or
other device, are two gripping pieces, each of which fits about seven eighths of half
the circumference of the carbon and their ends, conical on the outside only, lie at
the bases of the conical ends

page_text: When the two pieces are screwed together these pieces slide up the cones and in
so doing are forced inwards and firmly grip the carbon, still however preserving
their parallelism to the axis of the carbon. Thus, the carbon is held very firmly
and at the same time truly centered.
In adapting existing jointed gas brackets for electric lamps so that the wires.
may be passed through the joints without interfering with their action, I effect the
following alterations :-
I cut away the lower part of the plug which fits
lower pipe above the upper edge of the lower pipe
and the remaining part is bored out, only leaving
rigidity.
into the boss at the end of the
but still well within the boss
sufficient metal at the sides for,
The parts are put together and a thin screw put through the centre of this hole,
leaving equal space all round varying with the size of the bracket, and the plug
which usually exists at the top is made to serve as a nut; if there is no plug an
ornamental nut is made for the screw. The wire is passed down the pipes and
a coil spring made round the screw, which on the turning of the bracket from one
side to another is extended or compressed. One wire is usually passed and the
metal work of the brackets used for return but two wires may be passed, except
in small sizes.
A suitable stop is provided to prevent the bracket making more than one
complete turn.
In the case of an arc lamp being placed upon a bracket the terminals of the
lamp are placed within the casing and either the upper or the lower plate or
lower carbon holder is bored and tapped and screwed on where the gas burner
would have been and the wires pass within the case without being seen at all.
But in the case of an incandescent lamp being used on the bracket I provide
a special holder to screw onto the bracket to prevent the exposure of the wires.
This holder consists of two parts, the lower part has a female thread which fits
upon the nipple screw on the bracket, but swells out so that its upper extremity
takes a male thread over which screws à piece of thin tubing whose internal'
diameter is a trifle less than that of the neck of the incandescent lamp to be used,'
and whose upper edge is very thin and is slit in two or more places to make it
flexible..
:
The wires pass through the lower part and are fixed to two small hooks, either!
or both of which may be insulated or one or both wires may sometimes be fixed
into the lower part (preferably by running in bituminous insulating matter) and
their ends made into hooks. The upper part which is screwed for nearly its whole
length is screwed down, the lamp hooked on, and by screwing the upper part back
it is firmly fixed and good contact insured.
i
For automatically cutting the lamp out of circuit when the carbons are con-
sumed or when accident occurs, or for extinguishing it at will, without interfering'
with other lamps which may be on the same circuit I provide the following cut!
out.
A small solenoid is placed in a shunt circuit, and its armature is mounted on a
guide rod which hinges at one extremity to a small brass stop; into a notch in this
stop fits a metal bar hinged on a separate pivot and provided at its other extremity
with an insulating handle; the stop itself is also provided with an insulating
handle; the metal bar is pressed by a spring upon, a small metal block but on
raising it by its handle it catches the notch in the stop and is held there by a
spring. The connections are so arranged that when the metal bar is in contact
with the small metal block the lamp is cut out of circuit, and an equivalent'
resistance inay or may not be introduced.

page_text: ,
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Grice Statter in the Great Seal Patent Office on the
8th September 1883.
JOHN GRICE STATTER of Snapethorpe near Wakefield in the County of York
"IMPROVEMENTS IN ELECTRIC LAMPS AND FITTINGS THEREFOR
My invention relates to improvements in electric lamps and fittings therefor, the
object of my invention being to insure in a better manner than hitherto the
gradual feeding of the carbons in arc lamps as they are consumed without serious
intermittence or irregularity, to allow the lamp to be automatically cut out of
circuit when the carbons are consumed or become fixed, and to allow of, extin-
guishing any lamp or lamps out of a number without interrupting the main
current; the improvements also relate to an improved carbon-holder for arc lamps
and to improvements in adapting existing gas fittings for electric light fittings and
to an improved holder for incandescent lamps.
In order to enable my invention to be fully understood I will describe the same.
by reference to the accompanying drawing in which figures 1 and are elevations
partly in section shewing my improvements for effecting the gradual feeding of the
carbons as applied to a motor lamp; figure 3 is a diagram shewing the electrical
connections of the lamp; figures 4, 5 and 6 are views shewing a modification of
the arrangement shewn in figures 1 and 2; figure 7 is a diagram shewing the
electrical connections of the lamp; figure 8 shows a section of my improved carbon.
holder for are lamps; figure 9 is a section of my improved holder for incandescent
lamps and figure 10 an elevation of the holder with a lamp fixed therein. Figure 11
shews, the cut out", or arrangement I employ for automatically or at will
extinguishing any lamp or lamps out of the number without interrupting the main
current. Figures 1, 2, 4, 5, 6 and 10 are drawn to a scale of about half full size
and figures 8 and 9 are drawn full size. Similar letters in all the figures represent
similar or corresponding parts.
•
I will first describe my invention by reference to figures 1. 2, and 3.
In carrying out this part of my invention I effect the regular feeding of the
carbons in electric lamps, by means of the feed current in the following manner;
the lower carbon holder F is fixed and the upper one F is constructed of a brass
or other metal rack rod and descends upon the lower holder F by its own
gravitation.. A pinion d fixed on, the same spindle A as the armature a of a
dynamo electric motor engages with the teeth of this rack and the feed current
passing through the armature continually tends to raise the rack.
The chief parts of the mechanism are supported between two side plates D,
and D', which connect the upper and lower plates D" and D¹ and are screwed to
them. Between the plates D and D¹ is the armature a mounted on the spindle A
carrying a commutator c and the pinion d and surrounding the armature is the
electro magnet b, with curved pole pieces b' and 62.
This magnet is supported by plates e. and e². and is wound with thick wire.
A suitable construction of armature consists of thin curved iron plates which
are arranged edge to edge to form a ring; a depression is cut in the middle of
each plate which when they are arranged in order forms a groove down the centre
of the outer surface and in this groove soft iron wire is laid and soldered down,
leaving however the two ends free; two wires are also similarly soldered, one
round each outside edge, their ends being left free also, the ring can now be
stretched out flat, put into a lathe and wound; after the winding process it is
bent up, the end wires being then cut so as to form a dowel, which ensures good
contact for the two ends.

page_text: In the winding process each of the soft iron plates has wound upon it a distinct
coil and when cramped to the ring shape, these coils meet internally but leave
spaces on the outer surface.
The coils are then connected up to the commutator in the same manner as the
Paccinnoti coils.
The commutator has the same number of radial brass strips as there are coils
and is pressed upon by brushes f, f¹..
The pinion d, is fixed upon the shaft A so that the shaft and armature can
rotate to a certain extent before lifting the rack F-A collar g is keyed to the
shaft; in it is a groove h into which projects loosely a pin I fixed into the pinion d,
and before the current passes the pin is kept to one side of the groove h by a
spring; when however the current passes, the direction of rotation induced in the
motor is such that it moves until the pin catches the opposite side of the groove...
thereby extending the spring before the weight of the rack is borne by the motor.
On the outer side of the side plate D' is an arrangement which I call a balance for
short circuiting for an instant the dynamo electric motor. This arrangement.
consists of two solenoids, a main M and a shunt S resting on a brass plate K and
having their armatures m and 8 attached respectively to opposite ends of the,
balance arm L.
The arm L carries a pointer or contact maker 1, steadied by springs n, n! whose
tension can be regulated by a set screw; opposite the end of the contact maker is
a screw N supported on an insulated bracket. Thus when the shunt armature is.
attracted the contact maker 1, touches the screw N. I desire it to be understood..
that I make no claim to the method of placing the main and shunt coils as the
ordinary method of placing them on one former with a common axis and n
continuous armature would serve the same purpose, but for combination with the.
motor as shewn in figures 1 and 2 I prefer to place them as shewn while in the
hereinafter described modifications I prefer the ordinary method.
The electrical connections of the lamp are shewn in the diagram figure 3.
The ordinary main current starts from the positive terminal p traverses the
normal main coil M thence passes through the magnet and armature a of the
motor and then to the framework D, D¹, D D of the lamp; from the framework
it passes to the rack F, by a flexible cable O; it then passes through the arc and
returns by the lower carbon holder F and by a wire to the negative terminal q.
Another thick wire (shewn in dotted lines at N2) hereinafter designated "the
short circuiting wire" starts from the positive terminal and makes a coil.
designated the "short circuiting coil" round the main solenoid M and is then
attached to the insulated bracket supporting the screw N
It is not however necessary that this short circuiting wire should start directly
from the positive terminal. It may be tapped from the ordinary main circuit at a
point where, the main wire, leaves the coil on the balance as shewn at W in
figure 3. As figure 3 is only diagrammatic I will more particularly describe this
method of winding. The coil is bogun; leaving a long free end which I will call
the "bracket end;" when sufficient is wound on to form the short circuiting coil a
loop is drawn out and the winding of the coil continued until it is complete; the
wire is then cut off leaving another free end which is the outer end. The outer
end is connected to the positive terminal;-the loop is connected with the
magnets b, of the motor and the "bracket end" is connected to the bracket
supporting the screw N.
When the contact maker does not touch the screw N no current can pass by the
short circuiting path, but the moment the contact maker 1 touches the screw N
the short circuiting path is open and the greater part of the current flows by this
path causing the dynamo-electric motor to become feeble during that instant.
There is also a path for the current through the shunt coil of high resistance.
The action of the lamp is as follows:-
First as regards the motor. The current passing through the motor tends to
turn the armature a thereof in such a direction as to raise the upper carbon :

page_text: holder F: The force tending to bring the carbon holders with their carbons
together is constant as it is produced by the weight of the upper holder and the
force tending to separate them is that produced by the motor and depends on the
strength of the current passing through the motor which is the same as that passing
through the arc.
The maximum strength of the current passes when the carbons are in contact,
as they are when the current is switched on; the motor then starts and moves
round by itself until the pin I catches the side of the groove h in the collar g; it
has then sufficient power to raise the upper carbon holder F and to thereby
establish the arc. This introduces the resistance of the arc, and the current passing
through the motor is thereby weakened, but the power of the motor is still
sufficient to hold the upper carbon holder though not sufficient to raise it any
further.
. By the herein before described balance arrangement the lamp is made polyphote.
If the arc becomes slightly longer and the motor fails to regulate, more current
.passes through the shunt coil S, equilibrium between the main M and the shunt S
is destroyed, the shunt S overcoming the main M and the contact maker l, makes
contact with the screw N causing the greater part of the current to pass by the
short circuiting path shewn in dotted lines, thus short circuiting and enfeebling the
motor, but attracting the armature m and instantly breaking the contact between
the contact-maker and the screw N. If now the very small feed which has
taken place is sufficient to restore the equilibrium between the two solenoids M
and S no further action takes place but if not the action is repeated again and
again until equilibrium is restored.
·
In the arrangement shewn in figures 4. 5. 6 and 7 I dispense with the continuous
current type of dynamo motor the regulation being left entirely to the make and
break balance. But in this case the solenoids M and S, are placed one above the
other the main and extra main M being preferably above and the shunt S below
as shewn in figures 4 and 5; 1, is the contact maker pivotted at. P. and connected
to the armature by a pin working loosely in a slot at Q.
In the place of the dynamo electric motor I employ either one electro magnet or
two electro magnets.. In either case one electro magnet occupies the same position
in the circuit as was before occupied by the motor. In the arrangement shewn in
figures 4, 5. 6 and 7 two electromagnets are employed
a, and a', are the armatures and b, and 62, are the two electro magnets, or one
electro magnet and one solenoid may be employed and a second contact screw S¹, is
placed on the balance which is the sole regulator. The two electro .magnets b,
and 62, figure 6 are fixed in a suitable position to act upon the upper carbon
holder F, the object of the electro magnet b, being to strike or lengthen the are
while the electro magnet 62, which is included in the same circuit with the normal
main prevents by suitable mechanical means such as are hereinafter described, the
approximation of the carbons except during the instant when enfeebled by short
circuiting. The armature a, is attached to the separating mechanism and the
armature a¹, to the detent arrangement hereinafter described; when it is desired
to strike an arc varying in length with the strength of the current a solenoid is
employed in place of the electro magnet b,. The electrical connections of the
magnet b, are shewn in diagram at figure 7 and are as follows; the current is led
from the positive terminal p, round the convolutions of the magnet or solenoid
(as the case may be) to the insulated bracket S2 carrying the screw S¹. Hence
when the contact maker-l, touches the screw S¹ the magnet or solenoid b, is thrown
into parallel circuit with the normal main
The action is as follows: -when the normal main overcomes the shunt the
contact maker 1, makes contact with the screw S₁ the magnet or solenoid b, is
excited and by suitable mechanisın strikes the arc, the shunt now breaks the
contact between the contact maker l, and the screw S¹; as the arc increases in
length the shunt draws the contact maker l, down until it touches the feeding
screw N thereby short circuiting the detent magnet when a small feed takes place

page_text: and the contact is instantly broken by the passage of the current through-the.extra
main, this action is repeated as often as required to.compensate for the consumption
of the carbons.
The means which I have found suitable for striking the arc and feeding the
carbons are shewn in figure 6, and consist of a break wheel X keyed on the same.
shaft as the pinion d, acted upon by a brake block Y and a spring catch Z. The
periphery of the break wheel X is smooth on either side, but down the centre
there runs a ridge of ratchet teeth as shewn in figure 6. The brake block Y is
forked and strides over the teeth resting only on the smooth portion of the
periphery. It is pressed against the wheel X by the attraction of the detent
magnet 6, for its armature a¹, the spring catch Z is attached to the armature a,
and when raised by the attraction of the magnet or solenoid b, for its armature a,
engages with the teeth of the brake wheel X and rotates it to a certain extent
thereby raising F" and striking the arc.
Or I sometimes surround the break wheel X with a broad iron rim firmly fixed
to it which would form a continuous armature in place of the armatures above
described and shewn in figure 6 and in this case an electro magnet is supported in
bearings placed above the break wheel which bearings admit of a swinging motion
in a direction parallel to the plane of that of the wheel. The core of the magnet is'
continued downwards and a soft iron shoe is jointed to it so that it is also capable
of movement in the same plane, or parallel to the plane of the wheel. When the
lamp is not working, this shoe fits the iron circumference of the wheel but is
prevented from adhering too, closely by a brass piston which is forced upon the
iron rim by a spiral spring contained in a cylinder which is capable of adjustment
by screwing upwards or downwards.
An alternate method is to fit the shoe with a pawl at its extremity and screw
down the cylinder so that the pawl can only engage with the rim, which is then
made in the form of an iron ratchet wheel, when the magnetic attraction between
the shoe and the rim overcomes the action of the spring piston
The core of the magnet projects at its upper extremity in a direction parallel to
the plane of the wheel, the projection being preferably a separate piece of iron
bolted on to the top of the magnet's core; under this projection is an adjustable
block of iron, and outside the side plate is the balance arrangement exactly as
hereinbefore described when referring to figures 4. 5. and 6 except that the second
contact screw 'S' is not required
The current enters by the positive terminal traverses the main coil of the
balance and passes thence through the swinging electromagnet to the framework;
from the frame work it is given to the rack by a flexible cable similar to that
shewn at O figure 1. The other connections are similar to those herein before
described, viz, another path is open to the current through the short circuiting
wire and helix when the contact inaker nakes contact with its screw but this is
only instantaneous since the contact is instantly broken by the passage of the
current through the short circuiting helix, also there is the shunt coil of high
resistance always offering a passage for the current. Instead of pivotting the
contact maker 1, as herein before described I sometimes screw it into the iron
armature of the balance.
.My.improved carbon holder for electric lamps shewn in section in figure 8, is
constructed of a hollow cylinder consisting of two parts A and B' which screw
together as shewn, one of the ends of each of these parts is conical inside as shewn
at C and D' but the cones are bored through so as to fit the carbons loosely.
Within the cylinder and held in position by pins running easily in drill holes or
other suitable device, are two gripping pieces E' and G' each of which fits about.
seven eighths of half the circumference of the carbon and their 'ends, conical on.
the outside only, lie,at the bases of the conical ends of the cylinders A' and B'.
T
When the two pieces A and B are screwed together the pieces El and G' slide:
up.the.cones C.and D.and in. so. doing are forced inwards and firmly grip thei

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carbon, still however preserving their parallelism to the axis of the carbon. Thus
the carbon is held very firmly and at the same time truly centered
In adapting existing jointed gas brackets for electric lamps so that the wires
may be passed through the joints without interfering with their action I effect the
following alterations:-
I cut away the lower part of the plug which fits into the boss at the end of the
lower pipe above the upper edge of the lower pipe but still well within the boss
and the remaining part is bored out, only leaving sufficient metal at the sides for.
rigidity
The parts are put together and a thin screw put through the centre of this hole,
leaving equal space all round varying with the size of the bracket and the plug
which usually exists at the top is made to serve as a nut; if there is no plug an,
ornamental nut is made for the screw. The wire is passed down the pipes and a
coil spring made round the screw, which on the turning of the bracket from one
side to another is extended or compressed. One wire is usually passed and the
metal work of the brackets used for return but two wires may be passed except in
small sizes.
A suitable stop is provided to prevent the bracket making more than one
complete turn.
In the case of an arc lamp being placed upon a bracket the terminals of the
lamp are placed within the casing and either the upper or the lower plate or
lower carbon holder is bored and tapped and screwed on where the gas burner
would have been and the wires pass within the case without being seen at all
But in the case of an incandescent lamp being used on the bracket 1 employ.
the holder shewn in figures 9 and 10 which screws on to the bracket and prevents
the exposure of the wires. This bracket may be used with other incandescent
lamp holders
The holder shewn in figures 9 and 10 consists of two parts H¹ and I'; the lower.
part H¹ has a female thread at its lower part as shewn which fits upon the nipple
screw on the bracket and is enlarged at its upper part which is provided with a
male thread over which screws the upper part I of the holder whose internal
diameter is a trifle less than that of the neck of the incandescent lamp to be used,
and whose upper edge is very thin and is slit in two or more places to make it
flexible. The upper end is provided with a plug J¹ of suitable insulating material.
into which is screwed a hook K' forming one of the terminals and carrying a nut;
on the upper edge of the part H' is fixed the spiral connection L' forming the
other terminal: A hole is formed in the plug J' through which the wire is passed.
conveying the current and connected to the hook K by means of the nut on the
same as shown. The holder itself forms the return.
The upper part I which is screwed for nearly its whole length is screwed down,
the lamp hooked on, and by screwing the upper part back it is firmly fixed and
good contact insured. Or where a wire is employed for the return, both the lead
and return wires are passed through the lower part H¹ and their ends are formed
into hooks; they are then fixed in position, preferably by running in bituminous
insulating material. If required the lower part H' may be provided with a male
thread instead of the female thread represented.
For automatically cutting the lamp out of circuit when the carbons are consumed
or when accident occurs, or for extinguishing it at will, without interfering with
other lamps which may be on the same circuit, I provide the cut out illustrated in
figure 11.
:
.
A small solenoid S is placed in a shunt circuit and its armature a, is mounted on
a rod M' hinged" at one extremity to a small brass plate N³ having a stop N';
against this stop rests a.metal bar P¹ working in bearings at Q and provided at its
other extremity with an insulated lirndle; the plate having the stop N' is itself
also provided with an insulated handle R'; the metal bar P¹ is pressed against a
metal block W by a spring V fixed upon the block but, insulated from it; on
moving the bar P in the direction shewn by the arrow it catches into the stop.N'

page_text: which is held up by the spring V2; the spring V is attached to the insulated
hook X and acts against the attraction of the solenoid S for the armature a; by
altering the tension of this spring the moment of cut out may be determined.
The action is as follows: When the attraction of the solenoid S for its arinature a;
overcomes the spring V the stop N' is drawn downwards and releases P! which is
rapidly projected against W and held there by the spring V₁. An iron core a², is
introduced into the solenoid S to ensure the stop Ni being drawn down quickly.
The connections are so arranged that when the metal bar P₁ is in contact with the
block W the lamp is cut out of circuit and an equivalent resistance may or may
not be introduced at Y¹.
Having thus described my invention and the best means I am acquainted with
for carrying the same into effect I wish it to be understood that what I claim is
Firstly. In an electric lamp the employment of a balance mechanism in which
an extra main coil called the short circuiting coil is wound round the same former
as the main solenoid and is electrically connected up in such a manner that no
current can pass by it except when the shunt coil overcomes the normal main and
makes a passage for the current through the short circuiting coil to the frame work
of the lamp thus attracting the armature and instantly breaking the contact
substantially as hereinbefore described and represented in figures 1, 2 and 3 of the
accompanying drawing
Secondly. In an electric lamp the employment of a balance provided with the .
electrical connections herein before described and shewn in figures 1, 2 and 3 in
combination with a dynamo electric motor included in the same circuit as the
normal main coil of the balance substantially as herein before described and
represented in figures 1, 2 and 3 of the accompanying drawing
Thirdly. The modification of the arrangement of balance which in addition to
making an instantaneous contact when the shunt coil overcomes the normal main
makes a second contact when the main overcomes the shunt for the purpose of
causing the arc to be struck or lengthened substantially as hereinbefore described
and represented in figures 4, 5, 6 and 7 of the accompanying drawing
Fourthly. In an electric lamp the employment of a balance such as that shown
in figures 4, 5 and 7 in combination with an electro-magnet, the latter being
included in the same circuit with the normal main and which when energised
prevents by suitable mechanical or magnetic means the approximation of the
carbons except during the moment when the extra main is in circuit when it is
partially de-energised substantially as described
Fifthly. The general arrangement and combination of parts forming the cut
out substantially as hereinbefore described and represented in the accompanying
drawing
Sixthly. The method herein described of adapting existing gas fittings to render
them suitable for use with electric lamps substantially as herein before described
Seventhly. The combination of parts forming the improved carbon holder for
electric lamps substantially as described and shewn in figure 8 of the accompanying
drawing.
Eighthly. The general arrangement and construction of the improved holder for
incandescent lamps substantially as hereinbefore described and represented in
figures 9 and 10 of the accompanying drawing
In witness whereof I the said John Grice Statter have, hereto set my hand and
seal this sixth day of September in the year of our Lord One thousand eight
hundred and eighty three.