ELECTRIC ARC LAMPS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said James Brockie at the Office
of the Commissioners of Patents on the 29th May 1883.
JAMES BROCKIE of Brixton in the County of Surrey
ELECTRIC ARC LAMPS
"
"IMPROVEMENTS IN
My invention refers as hereafter described to various improved mechanical
devices applicable to arc lamps, and of improved methods of arranging and
constructing the same.
The first improvement consists of an appliance to retard the descent of the upper
carbon holder, or the too sudden approach of the carbons in an electric lamp; trains
of wheels, dash pots, gravity or balance wheels and such like being hitherto used
for that purpose. According to my invention I construct and employ a hollow disc
or cylinder having a weighted partition swung or pivotted on the axis of the said
disc, so that if the disc is rotated on a horizontal axis, the partition will remain in
a perpendicular position notwithstanding the rotation of the disc. I put in that
portion of the interior of the disc which is not occupied by the said partition, some
glutinous substance such as glycerine or oil; the disc or cylinder is then sealed as
closely as possible to prevent the leakage of the liquid. It will be seen that if
such a cylinder be now mounted on a horizontal axis and a weight or pressure less
than that of the pendulous partition be applied to turn the disc, the rotation of the
latter will be much hindered and slow as the partition will keep the fluid in a
practically fixed position and therefore the substance will cause a friction or drag
on the revolving interior surfaces of the disc; the amount of drag or hindrance
depending to a great extent upon the nature of the said substance; the more
glutinous or clinging the greater the amount of hindrance.
The interior of the disc or cylinder and the independent partition may be
constructed of different forms in order to present more surface to the frictional
or dragging effect of the substance; for instance a concentric ring loaded at one
side to prevent it turning with the disc may be substituted for the simple loaded

page_text: partition, a small space being left between the ring and the inside of the drum;
or the hollow drum may be channelled with concentric grooves having swinging
or rolling weighted obstructions.
Instead of employing solid obstructions or partitions as described a heavy
substance such as mercury may be used in combination with the lighter but more
glutinous substance in which case the said heavy substance would always occupy
the lower half of the interior of the disc and would therefore form a comparatively
stationary abutment against the glutinous substance, producing much the same
effect as with the solid partition or rolling obstructions before mentioned.
I sometimes also construct the swinging or obstructing partitions of iron and
place a magnet near the outside face of the disc in order to limit the movement
of the obstructing partition and so prevent the too sudden movement of the wheels
when a power is first applied; this application of a magnet being equivalent to
the employment of an exceedingly heavy pendulous obstruction the accommodation
of which would be impossible in the limited dimensions of a practicable disc.
In applying such a disc to an electric lamp I gear it to the carbon holder so that
the weight of the holder will rotate the disc, it may be geared to the holder by
means of a rack and pinion, or a cord wound on a drum on the axis of the disc or
by any intermediate gearing so that the descent of the holder will be comparatively
slow when the releasing brake or device is taken off the holders or disc.
Now in order to control the feed of the carbons in a lamp furnished with such a
dise I operate it by means of a grip or clutch working in a groove or grooves
formed in the side or sides of the said disc, this gripper acting with a locking or
jambing effect when tilted at one end and releasing its grip when depressed or
allowed to assume a more horizontal position; this gripper I gear to the active core
or armature of a solenoid or magnet in the lamp. Instead of making the locking
device work in grooves cut in the disc I sometimes construct it so that it operates
upon the periphery of the disc and on the inside of a ring concentric with the rim.
I also sometimes operate such discs by the friction of magnetism, in which case I
construct them of iron and bring a magnetized rubbing piece to bear upon their
surfaces; or the discs may be conveniently controlled by a jambing piece moving
between the face of the disc and a roller fixed near it, the said jambing piece filling
up the space between the said roller and disc, the jambing piece being made
either slightly taper or of an elastic substance, or the roller mounted on a flexible
bearing.
My invention also relates to a method of separating the carbons to obtain the arc
in an electric lamp which is regulated entirely and directly by a coil bridging the
arc. In all such lamps the carbons are apart when the current ceases and machines
separately excited or fitted with special self energising contrivances must be used
for such lamps. Now I place in such lamps a coil in the main circuit the duty of
which is to overbalance the weight or spring against which the regulating shunt
coil acts when no current exists in the circuit; but when a current is sent, the said
main coil armature retires from or puts into operation the regulating weight thus
allowing the spring to operate and lift the upper carbon holder; by this method of
arranging the duties of the main and shunt coils, lamps may be conveniently
constructed having only oue carbon bolder movable and at the same time entirely
depending upon the shunt current for direct regulation after the lamp is once
lighted
I sometimes construct lamps with two pairs of carbons and arrange the shunt
and main magnets as above described, but I employ a shunt coil to regulate each
carbon holder, the coil belonging to the second pair being put in circuit by the
carbon holder of the first pair when it arrives at a certain point; the main coil in
such lamps overbalancing both regulating weights or springs when no current
exists.
Another part of my Invention consists of an improved method of actuating the
sudden grip devices usual in direct acting lamps where such devices are released by
coming, upon a fixed stop or table. According to this part of my invention I move

page_text: the said stop or table in an opposite direction to the clutching device simultaneously
so that the operation of locking and unlocking may be performed with less travel
of solenoid core or magnet armature, the stop or table may be conveniently moved
by the reverse end of the lever which lifts the clutch. I also employ a movable
stop or table as a means of putting the second pair of carbons in a double lamp
into action, by causing the first holder on its descent to its lowest position, to raise
or tilt the releasing stop or table belonging to the second pair, thus enabling the
clutch of the said second pair to release its grip and then to regulate the second
pair at the same level as the first, or at practically the same position of solenoid
core.

page_text: JAMES BROCKIE of Brixton in the County of Surrey "IMPROVEMENTS IN
ELECTRIC ARC LAMPS"
My invention refers as bereafter described to various improved mechanical
devices applicable to arc lamps and to improved methods of arranging and
constructing the same.
Figures 1 to 6 shew in detail various forms of retarding wheels according to this
invention.
Figures 7 to 12 shew methods of working or controlling the same and
Figures 13 and 14 are improved methods of obtaining the arc in electric lamps.
The first improvement consists of an appliance to retard the descent of the
upper carbon holder, or the too sudden approach of the carbons in an electric arc
lamp; trains of wheels, dash pots, gravity or balance wheels and such like being
hitherto used for that purpose. Referring to Figures 1 and 14 of the accompanying
drawings I construct and employ a hollow disc or cylinder A having a weighted
partition B swung loosely on the axis C of the said disc, so that if the disc A is
rotated on a horizontal axis, the partition will remain in a perpendicular position,
notwithstanding the rotation of the disc, I fill that portion of the interior of the
disc which is not occupied by the said partition, with some glutinous substance
such as glycerine or oil, represented in the drawing by the dotted lines D; the
disc or cylinder is sealed as closely as possible to prevent leakage. It will be seen
that if such a cylinder be now mounted on a horizontal axis as shown in
Figure 1 and a weight or pressure less than that of the pendulous partition be
applied to turn the disc, the rotation of the latter will be much hindered and slow,
as the partition will keep the fluid in a practically fixed position and therefore the
fluid will cause a friction or drag on the revolving interior surfaces of the disc the
amount of drag or hindrance depending to a great extent upon the nature of the
said substance; the more glutinous or clinging, the greater the amount of
hindrance; The interior of the disc and the independent partition may be
constructed of various forms in order to present more surface to the frictional or
dragging effect of the substance for instance as in Figure 2 a concentric ring B¹
loaded at one side to prevent it turning with the disc may be substituted for the
simple weight just described, a small space being left between the ring and the
interior of the disc as shown; or as shewn in Figure 3 the disc may be channelled
with concentric grooves G G G and swinging or rolling weighted obstructions BBB
in combination with the glutinous substance before referred to. The drum may
even be constructed without any channels and the rolling obstruction may consist
of a single solid disc occupying the lower half of the drum; or instead of the
single solid disc small round or granulated substances such as lead shot may be
used in combination with the liquid.
Instead of employing solid obstructions or partitions as described a heavy
substance such as mercury may be used in combination with the lighter but more
glutinous substance in which case the said heavy substance would always occupy
the lower part of the interior of the disc Figure 4 shows this method, the
mercury B occupying the lower part of the disc and the glycerine D the upper
portion by making channels in the disc as in Figure 3 and using mercury (instead
of the balls) and glycerine a slower movement will be obtained as more surface
will be presented to the frictional action Figure 5 shows another construction of

page_text: disc this consists of an iron box B having partitions or divisions B¹ the
compartments formed by these divisions communicating at the axis; this box is
placed inside the disc A a small space being left between the two so that the iron
box is free to rotate on the boss of the outer box or hollow disc A. The inner box
is half filled with mercury M and the space between the two boxes A and B is
filled with glycerine or any suitable glutinous substance. It will be seen that the
mercury in the inner box B will keep it practically in a fixed position although
the outer box revolves. This particular construction of wheel is of some
advantage when the carbon holder of a lamp is geared directly to the wheel as in
Figures 7 and 9 for the mercury instantly finds its level however much the disc
may be disturbed in trimming the lamp.
I sometimes also construct the swinging partition B of iron as shewn in Figure 6
and place a magnet E near the outside face of the disc in order to limit the
movement of the obstructing partition and so prevent the too sudden starting of
the disc when a power is first applied; this application of a magnet being
equivalent to the employment of a very heavy pendulous obstruction, the
accommodation of which would be impossible in the limited dimensions of a
practicable disc.
In applying such a disc to an electric lamp I gear it to the carbon holder so that
the weight of the holder will rotate the disc; it may be geared to the holder by
means of a rack and pinion as shewn in Figures 7 to 12 or by a cord wound on a
drum on the axis of the disc or by any intermediate gearing so that the descent of
the holder will be comparatively slow when the releasing brake or device is taken
off the holder or disc; when intermediate gearing is employed, a much smaller disc
may be used than when it is driven directly by the rack of the carbon holder.
Now in order to control the movement of the carbons in a lamp furnished with
such a retarding disc I operate the disc by means of a clutch or gripper working in
a groove or grooves formed on the sides of the disc as shewn in Figure 7 this
gripper F acting with a locking or jambing effect when tilted at one end and
releasing its grip when depressed, the table or stop H limiting the downward fall
of the clutch; this clutch consists simply of a piece of metal F shewn in plan
Figure 8, the pieces K K being made a little longer than the width of the grooves G
cut in the sides of the disc A, when the clutch is lifted at the end L, the clutch
jambs in the grooves and so turns the dise; but when the end M rests upon the
stop or table H and the end L is depressed the clutch releases its grip on the inside
of the grooves and the disc is free to revolve in the opposite direction. I gear this
clutch to the core of the regulating solenoid which may be wound in the main
circuit, or in a shunt across the arc or differentially by both, so that the carbons
are adjusted as required.
Instead of making the locking device work in grooves cut in the sides of the disc
as explained I sometimes construct it so that it operates upon the periphery of the
disc and on the inside of a ring concentric with the rim as shown in Figure 9, the
clutch F is shown in plan in Figure 10 and consists of a piece of metal cut so as to
act upon the outside rim A of the disc and the inner rim B when this clutch rests
horizontally upon the table H the disc is free to turn but when the clutch is lifted
at the end L it locks itself on the disc and so turns it. I also sometimes operate
such discs by the friction of magnetism in which case I construct them of iron and
bring a magnetised rubbing piece to bear upon their surfaces in Figure 11 the
core P of the regulating solenoid S is brought to bear upon the rim of the disc A a
small piece of nonmagnetic metal or substance N being let into the core so that
when the core P arrives at a certain position this piece comes in contact with the
disc and the latter will be free to revolve; the action of this arrangement will be
as follows: when no current exists in the circuit the core P of the regulating
solenoid S will rest upon the stop H and the non-magnetic piece N will be in
slight contact with the rim of the iron disc A, the carbons will therefore be in
contact as the disc A. will be free to turn by the descending weight of the upper
carbon holder K; when however a current is passed through the lamp the core P

page_text: becomes magnetized and is drawn upwards into the coil S. when therefore the iron
part of the core comes in contact with the disc the attraction of magnetism causes
the adhesion of the disc to the core and as the latter is drawn upwards the disc is
turned slightly and the carbons are thus separated, when the arc becomes too long
the core gradually comes down turning the disc in the opposite direction and so
bringing the carbons nearer until when it arrives near its lowest position the non-
magnetic piece N comes in contact with the disc and the latter begins to slip round
and so the carbons are gradually adjusted. Figure 12 shows another method of
operating the disc where a jambing piece W is introduced between the disc A and
a roller R; as the core of the solenoid S ascends the disc is rotated and the carbons
separated and when the core arrives at or near its lowest position the pressure of
the spring is reduced and the slip of the disc takes place. The roller R may be
mounted on spring bearings
This invention relates also to a method of separating the carbons to obtain the
arc in an electric lamp which is regulated entirely and directly by a coil bridging
the arc.
In all such lamps the carbons are apart and remain so when the current
ceases, and machines separately excited or fitted with self energizing arrangements
must be used for such lamps. Now according to this part of my Invention I place
in such lamps a coil A. Figure 13 in the main circuit, the core B of which over-
balances the weight or spring against which the regulating shunt coil C acts when
no current exists in the circuit and so keeps the clutch D in its feeding position,
but when a current is sent through the lamp the said main coil armature or core B
retires from the regulating lever L and the arc is thus formed by the descent of
the shunt core S; during the working of the lamp the core B of the main coil A
remains in the position shown in the drawing and thus permits the shunt coil C
to regulate the lamp entirely but when the current ceases the core B drops on the
friction roller R at the extremity of the lever L and thus overbalances the weight
of the shunt core S the carbons are thus free to meet and the lamp is ready for
relighting when the current is again established. In such lamps I prefer to
complete the regulating shunt circuit when the core of the main solenoid arrives
at its topmost position; by this arrangement the work done by the main coil will
be much reduced as it will get the benefit of the dead weight of the shunt core
throughout its entire stroke, thus less wire need be wound on the main coil. A
modification of this plan is shown in Figure 14 and consists in placing a main
magnet A in a lamp to release a catch B which holds the regulating lever L in
such a position that the clutch D permits the carbons to meet; when no current
exists in the circuit the catch is in the position shown in the Figure but when a
current is sent the main magnet A attracts the armature M and so releases the
lever L allowing the shunt coil C to do the future regulation as in Figure 13 the
advantage of this method is, that a very small main coil may be used as its duty
is simply to release a catch, but a special self energizing or separately excited
machine must be used as the lever L may not be in a suitable position for being
locked by the catch when the current is taken off. The arrangement is only
necessary in lamps having a very slow movement of their carbon rods and which
are regulated entirely by a shunt coil.
I sometimes construct lamps with two pairs of carbons and arrange the duties
of the shunt and main magnets as described with reference to Figure 13 but I
employ a separate shunt coil to regulate cach pair of carbon holders the coil
belonging to the second pair being put in circuit by the holder of the first pair
when it arrives at a certain point and when the first pair of carbons are nearly
consumed; the main coil core in such lamps overbalancing both regulating
weights or springs when no current exists all as explained with reference to
Figure 13.
Another part of my Invention consists of an improved method of actuating the
sudden grip devices usual in direct acting lamps where such devices are released by
coming upon a fixed stop or table. According to this part of my invention I move
the said stop or table in an opposite direction to the clutch and thus the operation

page_text: of locking and unlocking may be performed with less travel of solenoid core, the
stop or table may be conveniently moved by the reverse-end of the lever which
lifts the clutch Figure 13 shows this method of operating the clutch D, the
regulating lever L lifts the clutch D by the link K and the other link K' is
depressed and so allows the clutch D to tip and secure its grip on the holder H in
less time than if the stop at that end was fixed I also employ a movable stop or table
as a means of putting the second pair of carbons in a double lamp into action by
causing the first holder on its descent to its lowest position, to raise or tilt the
releasing stop or table belonging to the second pair thus enabling the clutch of the
said second pair to release its grip and then to regulate the second pair at the
same level as the first or at practically the same position of solenoid core. This
method being employed when only one coil is used to regulate both pairs of
carbons directly by means of a clutching arrangement as used in many lamps the
releasing stop of the second pair of carbons in such lamps being at a different level
from the first.
Having now described the nature of the said invention and in what manner
the same is to be performed I declare that I claim.
First-In electric arc lamps the employment of hollow discs or drums having
swinging or rolling weights in their interior in combination with some glutinous
substance such as glycerine in, order to produce a slow movement of the carbons
when the controlling, mechanism is released substantially as described and with
reference to Figures 1, 1 A 2, 3, and 5.
Second-The employment in are lamps of hollow drums containing mercury or
any heavy granulated substance in combination with a glutinous substance
substantially as described and with reference to Figures 3 and 4
Third The employment of a magnet near such discs in order to limit the
play of the swinging weight substantially as described and with reference to
Figure 6
Fourth-Operating the regulating discs of electric lamps by means of a gripper
working in grooves in the sides of the discs or on their peripheries substantially
as described and with reference to Figures 7 to 10 and also working by the
friction of magnetism or by a jambing piece with reference to Figures 11 and 12
Fifth-In lamps which regulate entirely and directly by a shunt coil bridging
the are the employment of a main coil the core of which overbalances the shunt
core and regulating weight when no current exists; but when a current is sent the
said main coil core or armature retires and allows the shunt coil to operate the
carbons all substantially as described and with reference to Figures 13 and 14.
Sixth-In electric lamps operating the clutching device at both ends by the
same lever substantially as described and with reference to Figure 13.
Seventh-In double carbon lamps moving the releasing stop or table of the
second pair by means of the carbon holder of the first pair when it arrives at its
lowest position for the purposes set forth.
In witness whereof I the said James Brockie have hereunto set my hand and
seal this twenty ninth day of November in the year of our Lord One thousand
eight hundred and eighty three.
JAMES BROCKIE
(L.S.)