Year: 1897

page_text: Date of Application (in United Kingdom), 18th Dec., 1897
Complete Specification Left, 18th Oct., 1898-Accepted, 26th Nov., 1898
I, DANIEL LACKO, of No. 3, Rue de Savoie, Paris, in the Republic of France,
Electrician, do hereby declare the nature of this invention to be as follows:-
This invention relates to certain improvements in electric arc-lamps and more
especially to the means for controlling the motion of the carbons in lamps of that
class, whether at the time of kindling the lamp or in order to compensate for the
wear of the carbons, and it further comprises a novel method of fixing such carbons
in the carbon-holders.
All parts or devices which go to form the lamp and its carbon-controlling
mechanism are secured to a supporting plate.
This plate receives the tubes which serve to guide the carbon-holders and which
are connected by a cross tie at their lower ends."
The carbon-holders bave ends sliding in grooves provided in the tubes and aro
each connected with a counterpoise weight their weight being so adjusted that the
upper carbon-holder is heavier than the lower carbon-holder.
Onto the supporting plate there are secured two plates or lamina which serve
to support the shaft or spindle carrying a grooved pulley.
These plates or pulley brackets are connected with a further or top plate
adapted to receive a hook for suspending the lamp.
Along the groove of the pulley there passes a metal or other cord one end of
which is attached to the upper carbon-holder and the other to the upper extremity
of the counterpoise-weight connected with the lower carbon-holder.
The pulley is acted upon by a brake formed by the combination of three
separate parts viz. (1) a forked lever the two arms of which are linked to two
pivots or spindles supported by the plates or pulley brackets (2) another lever
pivotted to the forked lever and so arranged that a flat spring constantly tends to
move such pivoted lever away from the forked lever while a bent piece the portion of
which is adjustable limits the distance to which the two levers can be moved
apart; and (3) a brake-shoe movably mounted upon a pivot or spindle provided
on the pivoted lever such brake-shoe being embedded in the groove of the
pulley.
Below the free end of the forked lever supporting the constituent parts of the
brake there is arranged upon the bed or supporting plate a bobbin or coil formed
of a thin wire solenoid. In the centre of this coil is adapted to move a core

page_text: connected to the forked lever through the medium of a small connecting rod or link
pivotted at one end to the said core while its opposite end is jointed to the said
forked lever.
The vertical movements of the core and also consequently of the forked
lever are limited in the downward direction by a stop piece situated in the centre
and at the bottom of the spool or coil and secured to the supporting plate, and in
the upward direction by a screw supported by the top plate.
The forked lever is subjected to the action of a spring which constantly presses
it upwards. This spring rests upon a cross-piece connected by means of screws
with rods which in their turn serve to connect the supporting plate and the top
plate. A rod the upper part of which is linked to the forked lever while its lower
end slides in an aperture provided in the cross-piece, serves to guide the spring
whenever the said forked lever moves.
The top plate carries two binding screws or posts which receive the ends of the
wires serving to supply the lamp with current.
The positive post which is insulated from the said top plate is electrically connected
both with the upper carbon-holder at a point which is insulated from the guides or
tubes and the cord and with the point of entrance of the thin wire solenoid. The
negative post is connected with the point of issue of the said solenoid and to the
metal body of the lamp which is in electrical communication with the lower carbon-
holder.
The operation of the lamps is as follows :-
I will suppose the two carbons to be placed very far apart and the lamp at rest:
in this condition of things the spring by acting upon the forked lever presses
it against the adjusting or set screw and the brake-shoe acts upon the pulley
effectually checking any tendency of the same to move out of place."
In
When the current is sent into the lamp it reaches the same through the positive
post, but inasmuch as it cannot pass through the carbons which are far apart it
takes the direction of the negative post by passing through the solenoid.
passing through this solonoid the current causes the core to descend which as it
does so takes down with it the forked lever which in its turn compresses the spring.
This forked lever as it turns on the pivots sets in motion all the parts that go to
form the brake.
Now, owing to the eccentricity of the pivots in relation to the centre of rotation
of the pulley the shoe by the action of the forked lever aud the pivoted lever, is
moved away from the said pulley.
The brake shoe now no longer acts upon the said pulley: therefore this pulley is
at liberty to revolve and the excess of weight of the upper carbon-holder enables such
carbon holder to perform a downward movement and at the same time through the
medium of the cord to bring about an upward movement of the lower carbon-holder.
By such means then the two carbons draw nearer to and eventually touch each other;
and inasmuch as the resistance which these carbons now offer to the passing current is
less than the resistance of the solenoid the current will now pass through the upper
carbon-holder the two carbons, the lower carbon-holder and the body of the lamp,
leaving it through the negative post.
Since now the current passes through the solenoid no longer, the spring presses
the forked lever upwards and this lever carries the core up with it. With this
lever also therefore all the parts forming the brake must move. Owing to the
eccentric situation of the pivots in relation to the spindle of the pulley the brake-
shoe gradually comes nearer to the pulley, so that the brake comes to be applied to
this pulley before the forked lever has completed its upward movement. The
flexible connection between the pivoted lever and the forked lever enables, too, the
said brake to act upon the pulley gradually, the said pulley being allowed to
complete a slight rotary movement sufficient to allow the carbons to move as far
apart as is necessary for the illumination of the lamp.
The lamp therefore is by such means started; but subsequently the distance
between the ends of the carbons increases as a result of wear, and so does also the

page_text: resistance to the passing current increase at that point when this resistance become
greater than the resistance opposed by the fine wire coil the current instead of
passing through the carbons flows through the said coil direct to the negative post,
and as it travels through the coil it causes the core to move downwards by the same
process as has been previously described; the brake shoo is removed from the
pulley; this pulley recovers its freedom; the carbons move closer together and
finally meet; the current once more passes through them; the spring moves the
forked lever up again; and the brake shoe acts upon the grooved pulley and causes
it to perform a slight rotary movement which by moving the carbons away from
each other causes the arc to form.
In order to vary the amplitude of the oscillatory movement of the forked lover
and also consequently the amount of displacement of the device constituting the
brake and the extent of rotary motion which the pulley is to be allowed to perform,
to cause the carbons to move apart, it is only necessary to adjust the screw by
turning it in the top plate more or less.
It will be understood that the action of the carbon controlling mechanism will
invariably be the same in moving the carbons closer together or farther apart,
whether the object be to light the lamp or to compensate for wear.
The means which have hitherto been used in fixing the carbons in the carbon-
holders are inconvenient for practical purposes seeing that their employment
involves considerable loss of time.
In the lamp herein described the carbon-holders are provided with a special
device enabling the carbons to be secured in them very rapidly.
Each carbon holder is to this end provided with a projecting portion whereon is
fitted a washer intended to retain an oval socket which may be turned by means
of a handle. Within the said socket in a line with the projecting portion of the
carbon holder there is provided a piece identical with the said projecting portion in
shape but perfectly free to move.
A projection formed on the piece serves to guide this piece in its movement for
which purpose it is arranged to slide in a groove provided in the carbon-holder.
It will be readily understood that when it is desired to fit the carbons in position
all that is necessary is to shift the socket in such a manner as to enable the movable
piece to be moved away from the projecting part of the carbon holder so as to
allow of the insertion of the carbon between those two parts, and then to move back
the said piece bringing it nearer to the said projecting part again, which is effected
by causing the socket to perform a quarter of a revolution, when the carbon will be
firmly gripped and retained in place.
In the "locked "position the socket may be retained by slight pressure by a
projection carried by the stationary part, which projection engages in a groove of
corresponding shape formed in the said socket.
I, DANIEL LACKO, of No. 3, Rue de Savoie, Paris, in the Republic of France,
Electrician, 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 relates to certain improvements in electric arc-lamps and more
especially to the means for controlling the motion of the carbons in lamps of that

page_text: class, whether at the time of kindling the lamp or in order to compensate for the
wear of the carbons, and it further comprises a novel method of fixing such carbons
in the carbon holders.
The invention will be best understood by reference to the accompanying drawing
in which:
Figure 1 is a vertical section of the complete lamp along the axial line of the
tubes guiding the carbon-holders.
Figure 2 is a horizontal section on line 2-2 Figure 1.
Figure 3 is a partial section illustrating the operation of the carbon controlling
mechanism, aud
Figure 4 is a horizontal section on line 4-4 Figure 1.
All the parts or devices which go to form the lamp and its carbon-controlling
mechanism are secured to a supporting plate A.
This plate receives the tubes B which serve to guide the carbon-holders C and C¹
and which are connected by a cross-tie D at their lower ends.
The carbon-holders C aud C₁ have ends sliding in grooves d provided in the
tubes B and are cach connected with a counter-poise weight c and c¹ respectively
their weight being so adjusted that the upper carbon-holder C is heavier than the
lower carbon-holder C¹.
On to the supporting plate A there are secured two plates or brackets E which
serve to support the shaft or spindle f carrying a grooved pulley F. These plates
or pulley brackets E are connected with a further or top plate Gadapted to receive
a look for suspending the lamp.
Along the groove of the pulley F there passes a metal or other cord S one end of
which is attached to the upper carbon-holder C and the other to the upper
extremity of the counterpoise-weight c¹ connected with the lower carbon-holder C¹.
The pulley is acted upon by a brake formed by the combination of. three
separate parts viz. (1) a forked lever H the two arms h¹ of which are linked to
two pivots or spindles e supported by the plates or pulley brackets E; (2) another
lever I pivoted at i to the forked lever H and so arranged that a flat spring
constantly tends to move such pivoted lever I away from the forked lever H while
a bent piece 2, the position of which is adjustable, limits the distance to which the
two levers can be moved apart; and (3) a brake-shoe K movably mounted upon a
pivot, or spindle provided on the pivoted lever I such brake-shoe being embedded
in the groove of the pulley F.
Below the free end of the forked lever H supporting the constituent parts of the
brake there is arranged upon the supporting plate A a bobbin or coil M formed of
a thin wire solenoid. In the centre of this coil is adapted to move a core L
connected to the forked lever I through the medium of a small connecting rod or
link pivoted at one end to the said core L while its opposite end is jointed to the
said forked lever H.
The vertical movements of the core L and also consequently of the forked
lever Hare limited in the downward direction by a stop piece N situated in the
centre and at the bottom of the spool or coil M and secured to the supporting
plate A, and in the upward direction by a screw O supported by the top plate G.
The forked levor H is subjected to the action of a spring J which constantly
presses it upwards. This spring rests upon a cross-pieco j connected by means of
screws with rods a which in their turn serve to connect the supporting plate A
and the top plate G. A rod, the upper part of which is linked to the forked
lever H while its lower end slides in an aperture provided in the cross-piece j, serves
to guide the spring J whenever the said forked lever H moves.
The top plate G carries two binding screws or posts P and Q which receive the
ends of the wires serving to supply the lamp with current.
The positive post P which is insulated from the said top plate G is electrically
connected both with the upper carbon-holder C-at a point which is insulated from
the guides or tubes B and the cord S-and with the point of entrance of the thin
wire solenoid M. The negative post Q is connected with the point of issue of the

page_text: said solenoid and to the metal body of the lamp which is in slectrical communication
with the lower carbon-holder C¹.
The operation of the lamp is as follows:
I will suppose the two carbous to be placed very far apart and the lamp at rest:
in this condition of things the spring J by acting upon the forked lever H presses
it against the adjusting or set screw and the brake-shoe acts upon the pulley F
effectually checking any tendency of the same to move out of place. This position
of the parts is illustrated in Figure 1.
When the current is sent into the lamp it reaches the same through the positive
post P, but inasmuch as it cannot pass through the carbons which are far apart it
takes the direction of the negative post by passing through the solenoid M. In
passing through the solenoid the current causes the core. L to descend which as it
does so takes down with it the forked lever H which in its turn compresses the
spring J. This forked lever Has it turns on the pivots e sets in motion all the
parts that go to form the brake. Now, owing to the eccentricity of the pivots e
in relation to the centre of rotation of the pulloy F the shoe K, by the action of the
forked lever H and the pivoted lever I is moved away from the said pulley.
The position which the constituent parts of the carbon-controlling mechanism
occupy at this juncture is illustrated in Figure 3 of the drawing.
The brake shoe K now no longer acts upon the said pulley F; therefore this
pulley is at liberty to revolve and the excess of weight of the upper carbon-
holder C enables such carbon holder to perform a downward movement and at the
same time through the medium of the cord S to bring about an upward movement
of the lower carbon-holder C. By such means then the two carbons draw nearer
to and eventually touch each other; and inasmuch as the resistance which these
carbons now offer to the passing current is less than the resistance of the solenoid M
the current will now pass through the upper carbon-holder C, the two carbons, the
lower carbon-holder C' and the body of the lamp, leaving it through the negative
post Q.
Since now the current no longer passes through the solenoid M, the spring J
presses the forked lever H upwards and this lever carries the core I up with it.
With this lever also therefore all the parts forming the brake must move. Owing
to the eccentric situation of the pivots e in relation to the spindle f of the pulley
the brake-shoe K gradually comes nearer to the pulley F,so that the brake comes
to be applied to this pulley before the forked lever H has completed its upward
movement. The flexible connection between the pivoted lever and the forked
lever H enables, too, the said brake K to act upon the pulley F gradually, the said
pulley being allowed to complete a slight rotary movement in the direction of the
arrow Figure 1 sufficient to allow the carbous to move as far apart as is necessary
for the illumination of the lamp as shown in Figure 1.
The lamp therefore is by such means started; but subsequently the distance
between the ends of the carbons increases as a result of wear, and so does also the
resistance to the passing current increase at that point.
When this resistance becomes greater than the resistance opposed by the fine
wire coil M the current instead of passing through the carbons flows through the
said coil direct to the negative post, and as it travels through the coil it causes the
core to move downwards by the same process as has been previously described;
the brake shoe K is removed from the pulley F; this pulley recovers its freedom;
the carbons move closer together and finally meet; the current once more passes
through them; the spring.J moves the forked lever H up again; and the brake
shoe K acts upon the grooved pulley and causes it to perform a slight rotary
movement which by moving the carbons away from each other causes the arc to
form.
In order to vary the amplitude of the oscillatory movement of the forked lever H
and also consequently the amount of displacement of the devices constituting the
brake and the extent of rotary motion which the pulley Fis to be allowed to

page_text: perform, to cause the carbons to move apart, it is only necessary to adjust the
screw O by turning it in the top plate G more or less.
It will be understood that the action of the carbon controlling mechanism will
invariably be the same in moving the carbons closer together or farther apart,
whether the object be to light the lamp or to compensate for wear.
The means which have hitherto been used in fixing the carbons in the carbon-
holders are inconvenient for practical purposes seeing that their employment
involves considerable loss of time.
In the lamp herein described the carbon-holders are provided with a special
device enabling the carbons to be secured in them very rapidly.
Each carbon-holder is to this end provided with a projecting portion t whereon
is fitted a washer ¹ intended to retain an oval socket V which may be turned by
means of a handle v. Within the said socket V in a line with the projecting
portion t of the carbon holder there is provided a piece u identical with t in shape
but perfectly free to move. A projection u¹ formed on the piece u serves to guide
this piece in its movements for which purpose it is arranged to slide in a groove u²
provided in the carbon-holder..
:
It will be readily understood that when it is desired to fit the carbons in position
all that is necessary is to shift the socket V in such a manner as to enable the
movable piece to be moved away from the projecting part t of the carbon-holder
so as to allow of the insertion of the carbon between those two parts, and then to
move back the said piece u bringing it nearer to the said projecting part t again,
which is effected by causing the socket V to perform a quarter of a revolution, when
the carbon will be firmly gripped and retained in place.
In the "locked" position illustrated in Figure 4 the socket V may be retained
by slight pressure by a projection a carried by the stationary part t, which
projection engages in a groove of corresponding shape formed in the said
socket.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. An electrical arc lamp wherein the two carbon holders (C, C¹) of unequal weight
are connected together by a metal or other cord (S); such cord passing over a
pulley (F) subjected to the action of a brake (K) actuated by a lever (H) the move-
iments of which are controlled either by the movable core (L) of a solenoid (M) or
by a spring (J) in such a manner that the current when passing through the solenoid
causes the carbons to move closer together by removing the brake shoe from
contact with the pulley whereas when the current passes through the carbons the
said pulley has the brake applied to it but is allowed to perform a rotary movement-
sufficient to cause the carbons to move apart somewhat and the arc to form; this
process being accomplished whether it be desired to light the lamp or to
adjust the same substantially as specified with reference to the accompanying
drawing.
2. In an electrical arc lamp constructed in accordance with the 1st Claim a brake
formed by the combination of three separate parts viz. a lever (H) to which is
connected by some flexible mechanism a second lever (I) to which the brake-
shoe (K) is pivoted; the said lever H being furthermore connected by means of
jointed link () to the movable core (L) of a solenoid (M), and being subjected
to the action of a spring and adapted to turn on a pivot-point situated eccentrically to
the centre of rotation of the pulley (F) which undergoes the action of the brake
shoe K; in such a manner that when the core L is attracted by the solenoid M
and lowers the lever H, this lever as it descends, removes the brake-shoe K from
contact with the pulley F which is thus released, whereas when the core L is no
longer attracted by the solenoid M and when the lever H is pressed upwardly by
the spring J the brake-shoe K will gradually increase its action upon the pulley F

page_text: which will then perform a slight rotary movement; all as and for the purpose
specified with reference to the accompanying drawing.
3. In electrical arc lamps a method of fixing the carbons comprising an oval
sleeve or socket (V) adapted to be turned by means of a handle (v), such sleeve or
socket enveloping a portion (t) forming part or secured to the carbon-holder, and
a movable piece (u) between which the carbon may be locked; as hereinabove
specified with reference to the accompanying drawing.
4. An electric arc lamp constructed combined and operating substantially as
herein before described with reference to the accompanying drawing.
Dated this 18th day of October 1900
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.