Improvements in and connected with Electric Arc Lamps.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in and connected with Electric Arc Lamps.
I, JAMES BROCKIE, of 12, Tyson Road, Forest Hill, in the County of Kent,
Electrical Engineer, do hereby declare the nature of this invention to be as
follows:-
According to my invention and as applied for example to a lamp of non-focus-
sing type, I provide a drum or wheel having a spring so coiled within it, that by
means of a cord wound upon the drum and fixed to the lower carbon holder, the
latter is drawn upwards with a fairly even pull. I prefer to make the upper
positive carbon holder stationary, and insulate it from the base of the lamp. I
preferably and generally use a chain brake, but in addition to this brake, or in
addition to any other form of brake which may be used on an
provide a supplementary retarding device to the brake wheel.
the
arc lamp, I
This supplemental retarding device consists of a silk or other soft cord, placed
in a suitable groove in the brake wheel. The pressure or tension upon
auxiliary retarding cord is obtained by a spring which may be conveniently
mounted on a radius arm, which arm works on the boss or spindle of the brake
wheel. provide means to limit the play of this radius arm between say two
stops, or in a similar manner, so that although a considerable pressure may be
exerted by the spring upon the cord and brake wheel, the said wheel is quite free
to move a few degrees in either direction; this enables the regulating coils to
turn the brake wheel in a direction, to separate the carbons, and also to bring the
wheel back again to the feed point without any extra work being put upon them
by the drag of the auxiliary brake cord, the brake action of the said supplemental
cord only coming into play when the main brake is relaxed.
In some cases, 1 cause the pressure of the radius arm to act upon the regulating
brake-lever, in such manner, that when the brake wheel moves in the feeding
direction, it tends to turn the drag lever, and by extending it so as to abut against
a pin on the regulating rocking lever, a pressure is exerted on the said regulating
lever, in a direction opposite to that which permits of the feed, and in this manner
the feed or movement of the brake wheel tends to stop the movement and the
regulating coil is in this way assisted to check the feed.
I may utilize the radius arm as a contact to carry the current to the metal
wheel and conducting cord to the carbon, by attaching to the radius arm a metallic
flexible conductor.
In order to control the brake gear, I arrange a magnet consisting of two main
limbs upon which the wire of a shunt circuit to the arc is wound. I pivot the
yoke piece between the two lower poles and quite near to, but not touching them;
I connect the armature by two metal pieces or arms, and this armature is drawn
across the face of the two upper poles as the magnetic field becomes stronger. I
gear or attach one end of the chain brake to the rocking yoke, or to an extension
upon it, and thus gain leverage to enable the armature to exert considerable power
upon the brake chain or other brake gear. The strain upon the pivots is con-

page_text: siderably reduced by the disposition of the armature and yoke, the one being
pulled downwards and the other upwards.
I sometimes arrange lamps to keep the arc practically in a fixed position. In
this case I make both carbon holders movable, the top one causing the lower one
to ascend by its superior weight.
I provide two side tubes and I slot each of them at their lower halves. The
top part of the positive holder slides upon the outside of the upper half of the
tube, and the lower part of the holder enters into the inside of the same tube and
slides inside the lower half of it. A connecting rod, tape, or chain is attached to
this lower end, passes up the tube, and is connected by a tape or chain to the
brake wheel.
The negative holder slides inside the other tube, and its lower forked end
embraces and is guided by the tube. I insulate the positive holder from its metal
guide frame and conduct the current to it by a flexible cord.
The shunt regulating magnet and rocking armature may be applied to such
a lamp as last described, and in this case I wind one member in the main circuit,
and the other in a shunt to the arc, and I provide two yokes and armature so that
there are two distinct magnetic circuits, the connecting pieces or arms being of
iron. I arrange at the ends of the two rocking yokes two dises or cranks, one
having a short slot, and the other a pin which works in the slot.
The brake chain is attached to the rocking yoke belonging to the main magnet.
It will be seen that by this arrangement of magnets and armatures, that if no
current exists in the circuit the two armatures are free to fall apart by gravity or
by the action of a regulating spring or weight (if such be required); then when
the current passes, the main coil will attract its armature, and so the carbons will
be separated, and when by the action of the chain, the shunt coil becomes too
strong it will attract its armature in turn, and in so doing the pin will press
against the side of the slot in the main yoke, and thus press the main armature
away from its pole, until the brake chain is released sufficiently to permit the
carbons to get nearer each other.
Instead of making the two armatures independent, I sometimes connect the
two yokes rigidly, in which case the action is the same as in so-called differential
lamps.
In both lamps I use a metal frame, which conveniently carries the core and
coils, also the pivotted armatures and brake wheel in one self-contained piece,
the two terminals being used or applied to the top and bottom of the lamp.
The invention thus presents characteristic features by providing a supple-
mentary drag to the brake wheel, such drag being independent of the brake gear
or levers, and not coming into operation as the carbons are being separated, nor
as they are being brought to the feed position, but only operating as a drag when the
brake wheel is permitted to slide by the main brake relaxing its pressure. In a
non-focussing arc lamp the lower carbon being caused to ascend by the action of a
coiled spring or equivalent device, under the control of the regulating coils, while
both side rods are slotted at their lower halves only.. Moreover the two rocking
armatures are arranged in relation to each other, so that they are free when no
current exists, and act in opposition when the current is passing.
The regulating coils, armatures, and yokes are arranged so that the yokes rock
on their axis, and the armatures move across the face of the free poles, and the
drag device is arranged in some cases upon the regulating wheel so that the drag
helps to stop the rotation of the wheel.

page_text: Improvements in and connected with Electric Arc Lamps.
I, JAMES BROCKIE, of 12, Tyson Road, Forest Hill, in the County of Kent,
Electrical Engineer, 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 refers to improvements in and connected with electric arc lamps
wherein armatures, capable of being rocked across the face of the magnet poles,
are employed, the armatures being carried by arms mounted on an axis or axes
passing below the opposite ends of the poles, and the motion of the armatures is
caused to operate brake mechanism with the advantage of a leverage of the length
of the carrying arms. A supplemental drag to the brake mechanism is provided
such drag being independent of the brake gear and not coming into operation as
the carbons are being separated, nor as they are being brought to the feed
position, but only operating as a drag when for example the brake wheel or
equivalent is permitted to slide by reason of the main brake relaxing its pressure.
Rocking armatures are employed in some cases which are arranged in relation
to each other so that they are free when no current exists, and act in opposition
when the current is passing, and the drag device may be arranged in such manner
that it co-acts with the movements of the armatures in stopping the rotation of
the brake wheel or the like. In focussing lamps I arrange the carbon carriers so
that both side rods are slotted at their lower halves only. The invention further
relates to the construction of the lamps all as hereafter described.
In order that my invention may be readily understood I will now describe same
with reference to the accompanying drawings whereon Fig. 1 is a sectional front
elevation of, a non-focussing arc lamp, where the magnets are wound in a shunt
across the arc, constructed according to my invention. Fig. 2 is a sectional side
elevation of the same lamp, and Fig. 3 is a front elevation shewing the drag and
brake drum detached, and Fig. 4 is a sectional front elevation to shew the arrange-
ment of the axis from which the armatures are supported. Fig. 5 is a front
sectional elevation drawn to a larger scale than the previous figures of a part of
the regulating mechanism of my lamp, shewing an arrangement where the supple-
mental drag device co-acts with the movement of the armatures. Fig. 6 is a front
sectional elevation and Fig. 7 is a sectional side elevation shewing an arrangement
where the magnets are wound in the shunt and main circuits and the armatures
act in opposition when the current is passing. Fig. 8 is a front elevation shewing
the drag and brake drum detached. Fig. 9 is a detail view of the negative carbon
fork. Fig. 10 is a sectional side elevation, and Fig. 11 is a sectional front eleva-
tion drawn to a larger scale than the previous figures, shewing in greater detail
an arrangement where the magnets are wound in both the shunt and main circuits
and also giving an example wherein the drag or radius lever co-acts with the main
brake mechanism.
In the accompanying drawings and following description similar letters of
reference mainly refer to like parts in all the constructions.
Referring more particularly to Figs. 1, 2, 3 and 4, I provide a drum or wheel A
mounted loosely upon a fixed axle A¹; the drum contains a coiled spring A³
whereof one end is fixed to the drum, and the other end to the axle A¹, so that by
means of a cord B fixed at one end to the drum A, wound thereon, and having
its other end connected to the lower carbon holder C, the latter is drawn upwards
when the drum is free, with a fairly even pull by the action of the spring. The
cord B is fixed to the upper end of a guide rod C¹ which passes and is guided
within one of the side tubes C° C, and this side tube is slotted to allow of the

page_text: vertical motion of the lower carbon holder C, which is carried by the rod C¹ and
is formed with a guiding fork C at its other end to embrace the opposite side tube.
The upper positive carbon holder D) is made stationary, it being fixed to, but
electrically insulated from, the base E of the lamp.
Passing around the groove of the drum A is a brake chain or cord F one end
being attached to a spring F¹ secured to the base E of the lamp, and in order to
control the brake gear I arrange a magnet consisting of two main limbs G upon
which the wire of a shunt circuit to the arc is wound. I provide a yoke piece
composed of a pivotted shaft H passing beneath the lower ends of the poles G₁ of
the magnets G and in close proximity to same, as shewn by the detached side view
Fig. 4.
From this shaft H there are two arms H¹ extending upwardly and
carrying at their upper ends an armature J, capable of being drawn across the
upper faces of the pole pieces G₁ as the magnetic field becomes stronger. To the
pivotted shaft H, I gear or attach the end of the brake chain or cord F, and thus
gain leverage to enable the armature J to exert considerable power upon the
brake chain or other brake gear. The strain upon the pivots of the armature
shaft H is considerably reduced by the disposition of the armature J, and shaft H,
the one being pulled downwards and the other upwards.
In addition to the brake described, or in fact in addition to any other form of
brake which may be used upon an arc lamp, I provide a supplementary retarding
device to the brake wheel, such as is shewn detached at lig. 3, the position of
same being shewn in the lamp at Fig. 1. This device consists of a silk or other
soft cord K located in a suitable groove of the brake drum A, the cord K being
held in tension therein by being fixed at one end to a spring K³ carried by a
radius arm K2, mounted loosely upon the axle A¹, the other end of the cord K
being fixed to the radius arm K2 preferably by an adjustable tension device K³.
Any motion of the radius arm around the axle A¹ is limited by two stationary
stops K or by any convenient equivalent means. By this arrangement although
a considerable pressure may be exerted by the spring upon the cord K and brake
wheel A, yet at the same time the said wheel is quite free to be moved a few
degrees in either direction without the braking effect of the cord K coming into
action. This enables the carbons to be separated and the drum to be brought
back to the feed point without encountering extra resistance from the auxiliary
brake cord K, the brake action of the latter only coming into action when the
main brake F is released.
In the example described, the carbons are distanced before the current passes,
by the arms H1 and armature J having fallen back into the position shewn, the
brake chain F being thereby tightened and drawn back (the spring F allowing
of such motion) and the carbon holder C is thus lowered, the auxiliary brake K
not affecting this motion by reason of the free play of the radius arm K² between
the stops K. Upon current passing through the lamp, the arc is formed, and the
motion of the spring-actuated drum A, is controlled by the auxiliary brake cord K
and by the brake chain F connected with the rocking armature. When the
resistance between the carbons becomes greater, the magnets have greater energy,
and draw forward the armature J, thereby lessening the friction upon the drum A
and allowing the latter, by the action of its spring A³, to raise the lower carbon
holder C.
I may utilize the radius arm K2 as a contact to carry the current to the metal
brake wheel, and by a conducting cord to the carbon, by attaching to the radius
arm K² a metallic flexible conductor K5.
In some cases and as shewn by the enlarged detail view, Fig. 5, I cause. the
radius arm K2 to act upon the brake lever Hin such manner that when the brake
lever H¹ moves in the feeding direction, that is, to release the grip upon the
brake wheel A, it tends to turn the drag or radius lever K2; for this purpose the
radius lever K is extended so that projecting pins K thereon will act against a
projection K of the lever arm H¹, when the radius lever is rocked, whereby a
pressure is exerted against the said lever H¹, which pressure acts in a direction
?

page_text: opposite to that which permits of the feed and whereby the feed or movement
of the brake wheel A tends to cause a braking action to be brought about, which
greatly assists the regulating coil to control the feed.
I sometimes arrange lamps so as to be focussing, that is, to maintain the arc in
a fixed position. In this case I make both carbon holders movable, the top one
causing the lower one to ascend by its superior weight. Such construction is
shewn at Figs. 6, 7 8 and 9, wherein the two side tubes C C are each slotted
at their lower halves as shewn. The top part of the positive holder D slides upon
the outside of the upper half of the tube C2 and the lower part D' of the holder D
enters into the inside of the same tube C2, and slides inside the lower half of it,
as shewn by the detached and enlarged horizontal section of the parts at Fig. 9.
A connecting rod, tape or chain B is attached to this lower end D of the carbon
holder D, passes up the tube, and is connected to the brake wheel A.
The negative holder C slides inside the other tube C2 and its lower forked end C*
embraces, (see Fig. 9) and is guided by, the tube C2; the rod C¹ from the carben
holder C has a cord B connected to it, which cord extends upwards and is attached
to the drum A. I insulate the positive holder from its metal guide frame and.
conduct the current to it by a flexible cord D* as shewn.
The shunt regulating magnet G¹ and rocking armature J before described with
reference to Figs. 1 to 5 may be applied to such a focussing" lamp as last
described, but may employ a differential method as shewn at Figs. 6, 7 and 8.
In this latter case I wind one member G in the main circuit, and the other G in
a shunt to the arc, and I provide two spindles H H*, arms H H and arma-
tures JJ, there being two distinct magnetic circuits. At the lower ends of the
two rocking arms H' H are two discs or cranks L L', one crank L having a short
slot and the other crank L' has a pin L2 which extends into the slot of the crank L.
The brake chain F is attached to the rocking shaft H* of the main magnet G*, or
to a projection therefrom.
It will be seen that by this arrangement of magnets and armatures that if no
current exists in the circuit the two armatures J J are free to fall apart by
gravity as shewn in Figs. 6 & 7 or by the action of a regulating spring or weight
(if such be required); then when the current passes, the main coil G* will attract
its armature J and so the carbons will be separated, and when by the consumption
of the carbons, the shunt coil G becomes too strong, it will attract its armature J
in turn, and in so doing, the side of the slot in the crank L will come into contact
with the pin L3, and thus press the main armature J away from its pole until the
brake chain is released sufficiently to permit the carbons to get nearer each other.
In other respects the construction is similar to that previously described with
reference to Figs. 1 to 4, the auxiliary brake cord K being applied in like manner.
Figs. 10 and 11 are enlarged views shewing a construction precisely similar to
the lamp shewn at Figs. 6, 7 and 8, excepting that in this case the pin L³ co-acts
with the extension of the radius arm K2 as described with reference to Fig. 5.
Instead of making the two armatures independent I sometimes connect the two
yokes rigidly, in which case the action is the same as in so-called differential
lamps.
In both lamps I use a metal frame M which conveniently carries the core and
coils, also the pivotted armatures and brake wheel in one self-contained piece, the
two terminals N N¹ being used or applied to the lamp as shewn.
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:-
1. In electric arc lamps, the means for actuating the brake mechanism and
controlling the motion of the carbons, consisting in the combination with electric
magnets wound in a shunt circuit, of a pivotted shaft extending closely beneath
the lower poles of the magnets, arms, or an arm, extending from the shaft,
armatures or an armature carried by the other end of the rocking arms and capable

page_text: of swinging across the upper ends of the magnet poles, and a connection between
the pivotted shaft and the brake mechanism, whereby the latter is acted upon by
the rocking of the shaft, substantially as described.
2. In electric arc lamps, providing a supplementary drag device to the brake
wheel, such drag being independent of the brake gear or levers, and not coming
into operation as the carbons are being separated, nor as they are being brought
to the feed position, but only operating as a drag when the brake wheel is per-
mitted to slide, by the main brake relaxing its pressure, substantially as described.
3. In electric arc lamps arranging the supplemental drag device on the brake
wheel, and providing means whereby upon the drag coming into operation, it is
caused to also act upon the mechanism controlling the main brake and to aid in
bringing the latter mechanism into operation, substantially as described and with
reference to Fig. 5 of the accompanying drawings.
4. In electric are lamps the means for actuating the brake mechanism and
controlling the motion of the carbons, wherein two rocking armatures are
arranged in relation to each other, so that they are free when no current exists and
act in opposition when the current is passing, arranged and acting substantially
as and for the purposes described and illustrated with reference to Figs. 6 & 7 of
the accompanying drawings.
5. In electric arc lamps, the controlling mechanism, all combined arranged and
acting substantially as and for the purposes described and illustrated with
reference to Figs. 10 and 11 of the accompanying drawings.
6. In non-focussing are lamps, causing the lower carbon to ascend by the action
of a coiled spring or equivalent device controlled by the regulating coils, arranged
and acting substantially as described.
7. In focussing arc lamps, the arrangement and construction of carbon carrying
and guiding devices, and wherein the side rods are slotted at their lower halves
only, substantially as described and illustrated with reference to Fig. 6 of the
accompanying drawings.
8. The general arrangement and construction of parts composing my improved
focussing and non-focussing arc lamps, all constructed and acting substantially
as and for the purposes described and illustrated with reference to the accompany-
ing drawings.
Dated this 2nd day of March 1898
BREWER & SON,
London and Leeds, Agents for the Applicant.