An Improvement in Electrical Arc Lamps.
Year: 1893

page_text: Date of Application, 16th Dec., 1893
Complete Specification Left, 16th Aug., 1894-Accepted, 22nd Sept., 1894
PROVISIONAL SPECIFICATION.
An Improvement in Electrical Arc Lamps.
WILLIAM HARDING LAUDER 33 Blessington Street Dublin Ireland Photo-
grapher do hereby declare the nature of this invention to be as follows:-
―
My invention has for its object the more delicate feeding and the prevention of
over feeding of arc lamps when burning in series or when controlled by a series
solenoid the core of which would work in opposition to the core of a shunt
solenoid (shunt across the arc) or a compound wound solenoid or compound wound
magnets or any form of lamp in which the feeding is controlled by a series
operating against a shunt (magnets or solenoids) I insert a cut out in the shunt
circuit which may take the form of a brass lever pivotted in the centre with an
adjustable weight running along one limb holding the limb down and making
contact through shunt circuit. The other limb is in such a position as to be rested
on by the tripper which descends and undnes brake or clutch allowing the carbon
rod to feed forward or downward.
The manner in which these lamps generally work is as follows; the series
solenoid by the raising of its core strikes the arc and as the carbons burn away
the resistance between the points becomes greater which causes the shunt to
become more powerful and make its core operate against the series in such a
manner as to bring the carbons closer together reducing the resistance between
the points till the solenoids again balance each other in point of power.
The feeding as a rule is accomplished by the releasing of a brake or clutch
acting on a wheel which is geared on to the carbon rod or carrier or the releasing
of a brake or clutch acting direct on the carbon rod or carrier or the levelling of
a washer which jambs on the carbon rod or carrier by being dragged diagonally
across it.
These brakes or clutches are attached to the core of the series solenoid in such
a manner that when the core raises a certain distance it immediately applies the
brake and for the rest of its stroke it carries the carbon rod or carrier with it,
as the carbon burns away and resistance between the points increases the shunt
solenoid increases in power and its core works in opposition to the series making
it lower and bringing with it the brake or clutch and carbon rod or carrier this
lowering continues till a tripper attached to the brake or clutch meets with an
arranged opposition which gradually undoes the brake or clutch and allows of the
carbon carrier or rod slipping a little forwards or downwards bringing the carbon
points closer together and reducing the resistance between the points so much
ihat the series solenoid becomes stronger than the shunt its core raising at
once reapplying the brake and preventing the further downward or forward
movement of the carbon rod or carrier.
If the lamp has over fed the series core not only reapplys the brake or clutch
but keeps on separating the carbons till the resistance between the points makes
the shunt powerful enough to arrest the further movement of the series core.
In the case of the compound wound solenoid the only difference is that the shunt
and series wire are wound over each other on the one bobbin and operate on the
same core the shunt being wound in an opposite direction to the series winding
tends to make the core drop when the resistance between the carbon points arrives
at a certain point.
Compound wound electro magnets act on their armature which is attached to the
brake in a similar manner to the compound wound solenoid.
How I propose to make the feeding more delicate and prevent over feeding is

page_text: as follows; in the shunt circuit I insert a cut out which is so arranged as only to
cut the shunt out at the moment of feeding and reintroduce the shunt by the
preponderance of power given to the series when the shunt was cut out.
The cut out might take the following form.
A brass lever pivotted in the centre with an adjustable weight running along
one limb which keeps this end of the lever down making contact through the
shunt circuit the other end of the lever is rested on by the tripping.arrangement
that descends and takes the brake or clutch off the carbon rod or carrier allowing
it to slip downwards or forwards.
To adjust for working I run movable weight along limb till the amount of
resistance offered at the other end of the lever to the tripper of the brake or
clutch or the levelling of the washer is such that the contact through the shunt
must be perfectly or partially broken before it is possible for either washer to
level or the tripper to get enough purchase to undo the brake or clutch
sufficiently to let the carbon rod or carrier slip forward or downward the result
of this is that simultaneously with the brake or clutch being taken off the carbon
rod or carrier the shunt is cut out leaving the series solenoid alone and freed from
the shunt's opposite action to operate in a decided manner lifting its core and
gear reapplying the brake and only stopping when having reintroduced the shunt
it is rebalanced by it. These movements take place so rapidly that at no time
does the lamp over feed providing it is properly adjusted.
It is not necessary for the shunt circuit to be completely broken all that is
requisite is, at the moment that the brake or clutch undoes to make its tripper which
rests on one limb of the lever introduce at the weighted end of lever a sufficient
resistance in the shunt circuit as to give to the series coil a decided and
immediate preponderance of power enabling its core to raise reapply the brake
and only stop when it had cut out the introduced resistance in the shunt circuit.
If the series solenoid failed to reapply the brake or clutch on the cutting out
of the shunt solenoid the brake would be instantly reapplied by the lowering of
the opposition offered by the limb of the lever rested on by the tripper of the
brake or clutch or the partially levelled washer.
15th December 1893.
WILLIAM HARDING LAUDER,
33, Blessington Street, Dublin, Ireland.
COMPLETE SPECIFICATION.
An Improvement in Electrical Arc Lamps.
I, WILLIAM HARDING LAUDER of 33 Blessington Street Dublin Ireland,
Photographer, 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 :-
My invention has for its object the more delicate feeding and the prevention of
over feeding of arc lamps, when burning in series, or when controlled by a series
solenoid, the core of which would work in opposition to the core of a shunt solenoid
(shunt across the arc) or a compound wound solenoid, or compound wound magnets,
or any form of lamp in which the feeding is controlled by a series operating
against a shunt (magnets or solenoids).
To carry out my invention I insert a cut out in the shunt circuit, which may take
the form of a brass lever pivotted in the centre having an adjustable weight
adapted to run along one limb of the lever, weighing this limb down, and making
contact through the shunt circuit. The other limb of the lever is in such a position
as to be operated by the tripper of the carbon brake, or clutch, which in descending
undoes the brake or clutch, and allows the carbon rod to feed forward or
downward.

page_text: The manner in which this class of lamp generally works is as follows:-The
series solenoid by the raising of its core strikes the arc, and as the carbons burn
away, the resistance between the points becomes greater, which causes the shunt
solenoid to become more powerful, and makes its core operate against the series
core, in such a manner as to bring the carbons closer together, and thus reducing
the electrical resistance between the points of the carbons, till the solenoids again.
balance each other in point of power.
The feeding, as a rule is, accomplished by the releasing of a brake or clutch
acting on a wheel, which is geared into the carbon rod or carrier; or the releasing.
of a brake or clutch acting direct on the carbon rod or carrier; or the levelling
of a washer which jambs on the carbon rod or carrier, by being dragged diagonally
across it.
a manner,
These brakes or clutches are attached to the core of the series solenoid in such
that when the core rises a certain distance, it immediately applies the
brake and for the rest of its stroke, it carries the carbon rod or carrier with it, as
the carbon burns away and the resistance between the points increases, the shunt
solenoid increases in power, and its core works in opposition to the core of the series
solenoid, making it take a lower position, and bringing with it the brake or clutch
and carbon rod or carrier; this lowering continues till a tripper attached to the
brake or clutch meets with an arranged opposition or obstruction which gradually
undoes the brake or clutch and allows of the carbon carrier or rod slipping a little
forwards or downwards, bringing the carbon points closer together and reducing
the resistance between the points so much that the series solenoid becomes stronger
than the shunt solenoid, the series core lifting at once, reapplying the brake and
preventing the further downward or forward movement of the carbon rod or
carrier.
If the lamp has overfed the series core not only reapplies the brake or clutch
but keeps on separating the carbons till the resistance between the points makes
the shunt solenoid powerful enough to arrest the further movement of the series
core. In the case of the compound wound solenoid, the only difference is, that the
shunt and series wire are wound over each other on the one bobbin and operate on
the same core; the shunt winding, being wound in an opposite direction to the
series winding, tends to make the core drop when the resistance between the carbon
points arrives at a certain point.
Compound wound electro-magnets act on their armature, which is attached to
the brake in a similar manner to the compound wound solenoid. I propose to
make the feeding more delicate and prevent over feeding in the following
manner: In the shunt circuit I insert a cut-out or resistance-varying device
which is so arranged as only to cut the shunt circuit out or increase the resistance
in the shunt circuit at the moment of feeding and reintroduce the normal shunt
circuit by the preponderance of power given to the series solenoid when the shunt
circuit was cut out.
The cut out may take the following form:-
A brass lever, pivotted in the centre with an adjustable weight running along
one limb, which keeps this end of the lever down making contact through the
shunt circuit; the other end of the lever is adapted to engage with the tripping
arrangement during its descent, and takes the brake or clutch off the carbon rod
or carrier, allowing the latter to slip downwards or forwards.
To adjust for working, I run a movable weight along the limb till the amount of
resistance offered at the other end of the lever to the tripper of the brake or clutch
or to the levelling of the washer, is such, that the contact through the shunt must be
perfectly or partially broken before it is possible for either washer to level, or, the
tripper to get enough purchase to undo the brake or clutch sufficiently to let the
carbon rod or carrier slip forward or downward; the result of this is that,
simultaneously with the brake or clutch being taken off the carbon rod or carrier,
the shunt circuit is cut out, leaving the series solenoid alone and freed from the
shunt solenoids' opposite action, to operate in a decided manner, lifting its core and

page_text: gear, reapplying the brake and only stopping when-having reintroduced the shunt
circuit, it is rebalanced by the action of the shunt solenoid. These movements
take place so rapidly that at no time does the lamp overfeed, providing it is
properly adjusted.
It is not necessary for the shunt circuit to be completely broken, all that is
requisite is, at the moment that the brake or clutch undoes, to make its tripper,
which rests on one limb of the lever, introduce at the weighted end of the lever a
sufficient resistance in the shunt circuit, so as to give to the series coil a decided
and immediate preponderance of power, enabling its core to rise to reapply the
brake, and only to stop in its motion when it has cut out the introduced resistance
in the shunt circuit.
If the series solenoid failed to reapply the brake or clutch on the cutting out of
the shunt solenoid, the brake would be instantly reapplied by the lowering of the
position of the obstruction or opposition offered by the limb of the lever, operated
on by the tripper of the brake or clutch, or the partially levelled washer.
In order that my invention may be the better understood I will now proceed to
describe the same in relation to the drawing hereunto annexed reference being
had to the letters and figures marked thereon; by way of illustration I have shown
it in connection with my improved lamp as described in the Specification of Letters
Patent No. 933 of 1893 as granted to me.
Fig. 1 is a view of a lamp with my invention fitted thereto.
Fig. 2 is an enlarged detail view of the cut-out and
Fig. 3 is a diagrammatic view of the circuits.
The lever a is of metal and pivotted on the ebony support j at the point in
such a manner as to allow of the contacts h and being separated, when the
pressure is applied on the ebony block c by the contact with it of the clutch
weight o in its descent; d is an adjusting screw which rises under the ebony block c
and prevents the points h and r separating too far e is an adjusting weight which
runs along the lever a and is fixed at any desired spot by screw.
The contacts and r may be of platinum or faced with any other suitable metal,
these points and are connected with the two ends of the wire ou coil y which
may be of very high resistance.
The clutch in Figure 1 has the traversing lever m pivotably connected at its
extreme ends with the cores of two solenoids p and q, p being the series solenoid
and the shunt solenoid wound with wire of high resistance.
The shunt coil has one end connected with the negative terminal of the lamp
and the other end connected with a metal arm a by the binding screw i and makes
contact with the upper body of the lamp which is positive, through the points hr
when they are closed; and through coil g of high resistance wire when they are
opened, by the pressure of the clutch weight d resting on the ebony block c which
is fastened to the end of the arm a.
To adjust for working I run the weight e along the limb of lever a till there is a
sufficiency of resistance offered at c to the clutch weight o to ensure the clutch
being slightly released before the points h and r can be separated by the pressure
of the clutch weight o resting on the point c.
When the current is switched on to the lamp the series solenoid p becomes
strongly magnetised and attracts its core k upwards lifting the traversing lever m
and clutch gear till the weight o leaves the ebony block c when the clutch fastens
on the carbon rod lifting it with it, for the remainder of the lift of the series core k
separating the carbons or striking the arc.
At the moment that the clutch weight o leaves the point c the contacts and r
'come together and cut the high resistance coil which was introduced into the shunt
circuit by their being separated.
As the carbons burn away and the resistance between their points increases the
shunt solenoid 9 becomes more powerful and attracts its core which operates
against the pull of series core k making it gradually lower its position and bringing
the clutch gear with it.

page_text: This lowering continues as the carbon consumes away till the clutch weight o
rests on the point c thus gradually releasing the clutch, but simultaneously with the
clutch being completely released, the weight o out balances the resistance of the
adjusting weight e, and the points separate introducing the coil of high
resistance wire g into the shunt circuit, which at once weakens, the pull of the
shunt coil q on its core the result is that the series solenoid p becomes the more
powerful, and operating its core k, raises, and reapplies the clutch only stopping
in its upward movement, when the weight o is sufficiently lifted off the point
to allow the contacts hr to close and cut out the introduced resistance g, which
again establishes an equilibrium of power between the two solenoids, the above
movements keep on repeating themselves automatically and so rapidly, that before
the carbon can feed forward or downward more than an imperceptible amount, the
clutch is reclosed.
The high resistance coil g is not necessary and is only used to prevent too
violent a pull by the series solenoid, consequent on completely cutting the shunt
circuit, this coil g is introduced at a particular moment into the shunt circuit to
weaken it and give a preponderance of power to the series compelling it to raise
its core and reapply the clutch and prevent the further descent of the carbon
rod. The same object would be obtained in a more decided manner by discon-
necting the ends of high resistance wire g from points r, the result being that
when these points separated, the shunt circuit would be completely broken,
and the series coil p would reclose the clutch in a more decided manner than
under the conditions herein before described. The method of using this invention
with lamps controlled by a compound wound solenoid or compound wound magnets
would be identical with the above, making the tripper or some other part of the
clutch mechanism, cut or introduce into the shunt circuit at the moment the clutch
became undone, a resistance sufficient to give an immediate preponderance of
power to the series solenoid enabling it to lift its core, reapply the brake and cut
out the resistance introduced into the shunt circuit or make a perfect contact in
the shunt circuit, should it have been broken. I do not bind myself to the above
arrangement, but claim any of the many well known arrangements for making and
breaking contacts or cutting out and inserting resistance, to be used in a similar
manner and for the purposes described.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1st. In an electric arc lamp in which the regulation of the carbons is effected by
the differential effect of a coil in series with the lamp and a coil in a shunt circuit
across the arc, a device adapted to vary the resistance in the shunt circuit, in
combination with the clutch gear for holding the carbons, or with the carbon
holders, in order to reduce or cut out the influence of the shunt coil upon the
carbon or carbon holders when the clutch is released, substantially as described.
2nd. In an electric arc lamp as claimed in Claim 1, a regulating device,
consisting of a movable lever having an adjustable recoil device adapted to operate
a cut-out or resistance varying device in the shunt coil, in combination with a
retaining clutch or holding device for the carbons adapted to operate the cut-out
or resistance varying device when the clutch is released substantially as described.
3rd. The arrangement and construction of a regulating device for electric are
lamps, substantially as described and shown in the accompanying drawings.
Dated this 16th day of A wœust 1801
FELL & WILDING,
Agents for the Applicant.