IMPROVEMENTS IN ELECTRIC-ARC LAMPS
Year: 1883

page_text: LETTERS PATENT to Conrad Wücst of Zurich, Switzerland (Director of the
Zurich Telephone Society at Zurich.) for an Invention of IMPROVEMENTS
IN ELECTRIC-ARC LAMPS
PROVISIONAL SPECIFICATION left by the said Conrad Wüest at the Office
of the Commissioners of Patents on the 29th June 1883.
CONRAD WÜEST, of Zurich, Switzerland, (Director of the Zurich Telephone
Society at Zurich) IMPROVEMENTS IN ELECTRIC-ARC LAMPS
My invention relates to electric are lamps, the carbons of which are fed by means
of rollers, whereby their resistance is made independent of their length.
The lamp is constructed as follows: The carbon holders consist of two pairs of
grooved rollers. Each pair holds a rod on two sides and is supported by a frame;
one of the rollers of each pair is mounted in a separato sliding frame and is
pressed against the other roller by a spring. The carbon rods are enclosed between
the two pairs of rollers and moreover guided by fixed rings. By turning the
rollers in one or the other sense, the two carbons are moved apart or nearer to each
other. One of each pair of rollers is provided with teeth gearing into one of two
screws or worms which have the same axis, but are insulated from each other and
wound in different directions.
•
The double, screw receives motion by means of a mechanism composed as
follows:
An electromagnet the armature of which is supported by a pivoted lever.
A spring secured to the said lever pulls the arinature away from the poles. The
top end of the lever is provided with a piece of ebonite for the purpose of
periodically interrupting or closing the current which excites the electro-magnet.
The to and fro motion of the lever is utilized to turn the double screw. For this
purpose two light rods are provided at their extremities with pallets moving on a
hinge-joint. The said pallets gear alternately into a toothed wheel on the shaft of
the screw. The said wheel has two parallel sets of teeth placed so that the screws
can be turned right or left, according as one or the other of the pallets gears with
its respective wheel.
The electro-magnet is influenced by the current during the whole time the

page_text: anchor approaches towards the poles, whilo during the whole time of its receding
motion the electro-magnet is completely currentless. Only a small part of tho
current is employed to excite the electro magnet. For this purpose a branch
current is taken out of the main current and led to a sliding block, softly pressed
upon a plate by a light spring. A metallic pin insulated from the said plate is
placed before the said sliding block which when making contact with it transmits
the current to the electro magnet, and further again to the main current, and
positive carbon. In order to force a part of the main-current to pass through the
branch couducting wire a resistance of about 1/8 Ohm is interposed in the main
current. The electric current is interrupted when the sliding-block is withdrawn
from the metallic pin by the motion of the lever.
The spring now moves the anchor away from the electro-magnet, and at the
moment of its farthest distance, the sliding block is again brought in contact with
the pin closing the current & attracting the armature, the current remaining closed
until the armature has approached nearest to the magnet. The motion of the
double screw and therefore of the carbon rods is determined by a regulator which
consists of two solenoids one of which is influenced by the main current and the
other by a differential current. Both solenoids tend to attract an iron core
provided with a pin which moves the two pallet-rods and gives them a
horizontal motion according as one Solenoid or the other acts stronger, and one or
the other of the two pallets gears into the wheel, turning it to the right or to the
left, whereby the carbon rods approach or go apart. New is the entire balancing
of the core which is suspended to small links whereby the moving of masses is
avoided and friction reduced to a minimum. In order to avoid the continual
movement given to the armature by the electro-maguot an interruptor is applied,
permitting motion only, when the sliding of the carbon rods becomes necessary,
and one of the pallets is in gear with the toothed wheel. For this purpose tho
core of the solenoids has the function, besides that of a regulator, to lead or
direct the contact of the sliding block with the pin which takes place in the
following way.
A small shaft turns on the points of two screws; it is placed at right angles to
the core of the solenoids and turned a little by a pin gearing into a small crank
when the core moves between the solenoids. The upper half of the shaft is cut
out at the place where it traverses the contact pin.
On the surface of the cut out part of the shaft which is insulated with ebonite,
stand two little adjusting screws screwed into a frame. By the least turning of
the shaft the cut out surface becomes inclined, and lifts one of the adjusting screws
with the frame and in consequence also with the contact pin which then comes in
contact with the sliding block and brings in activity tho electro-magnet which
moves the carbon rods until the cut out surface of the shaft is horizontal, whereby
the pin sinks and get out of contact with the sliding block.
In case one lamp. gets out of order, and to prevent the others of the same
electric circuit to do the same, an automatic resistance equal to the resistance of
the arc light, is interposed as follows. Two bobbins standing on a wooden plate,
one being wound with thick, the other with thin wire, which are both continuations
of the coils of the solenoids and influenced by the same currents; they tend to
attract the iron armature which is slightly pressed on the core of one of the
bobbins by a small spiral spring. If now the carbon rods are too much apart so
that the main current is interrupted the first bobbin loses its attraction while that
of the second is augmented and attracts the armature leading the main current
through a resistance wire to the negative clamp. The driving mechanism and
regulator continue to work. If the carbon-rods touch each other, the current takes
its way through the first bobbin which attracts the armature and interrupts the
circuit.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Conrad Wüest in the Great Seal Patent Office on the 28th December
1883.
CONRAD WÜEST, of Zürich, Switzerland, (Director of the Zürich Telephone
Society at Zürich) "IMPROVEMENTS IN ELECTRIC-ARC LAMPS"
My invention relates to electric arc lamps, the carbons of which are fed by
means of rollers, whereby the resistance of the carbons is made independent of
their entire length.
In the following description reference will be made to the accompanying
drawings, of which:
Fig 1 and 2 are elevations of the lamp at right angles to each other; Figs 3
and 4 show upper and lower roller frames in detail; Fig 5 is a plan partly in
section, and Fig 6 shows some parts in detail.
The carbon rod holders consist of two pairs of rollers 71, 72 and 7³, 74 (Figs 1, 2,
3 and 4) provided with annular grooves adapted to receive the carbon rods. Each
pair is placed in a frame R, R', Figs 3 and 4; one of the rollers of each pair 71
and is mounted in a separate sliding frame pressed against the other roller
or by a spring. The carbon rods are held between the two pairs of rollers and
moreover guided by fixed rings f, f. By turning the rollers one way or the other,
the two carbons are moved apart or towards each other. In order to turn the
rollers, the rollers and are provided with teeth made to gear into right and
left hand screws S and S' (Fig 1) cut or formed on spindles which are coupled
together by an insulating coupling . The pitch of screw S is double that of
screw S' on account of the quicker burning of the positive carbon. According
to the direction in which the worms S, S' are turned, the carbon rods approach
each other or go apart.
The double screw S, S¹ receives motion by means of mechanism placed partly
beneath and partly above the plate P (Fig 1 and 2). This mechanism comprises
an electro magnet E, the armature a of which is supported by lever / pivoted on
axle n. The spring b (Fig 1 and 5) attached to lever h tends to pull the armature a
away from the poles. The top end of lever h is provided with a piece of ebonite
for the purpose of periodically breaking or closing the circuit which excites the
electro-magnet E. The to and fro motion of lever h is utilised to turn the double
screw S S. For this purpose two light rods p, p¹ are pivoted to a yoke / fixed on
lever h. Each of the rods ppl is provided at its extremity with a hinged hook k, k,
pressed upon by a small spring k³. These hooks or pawls k gear alternately into
a toothed wheel R on the shaft of the screws S S'. Wheel R has two rows of
teeth placed in opposite directions, so that the screws S S¹ may be turned right
or left, according as the pawl k or the pawl k' is in gear with its respective wheel.
It must be remarked, that the electro-magnet E is influenced by the current as
long as the armature a approaches towards the poles, while during the whole time
of its receding motion the electromagnet is completely currentless.
By this means the electro-magnet is capable of doing considerable work, which
would not be possible to obtain if the opening and closing of the current would
take place as with Wagner's hammer, or with electric alarms..
As only a small portion of the current is required to.influence the electro-
magnet, (about 1/100) a branch current is taken out of the main current at x
(Fig.1 and 5) and led to the sliding block t, softly pressed upon plate u by a light
spring f. A metallic pin & insulated from the plate u by ebonite is placed before
the sliding block t, which when standing upon it, and making contact with it

page_text: transmits the current to the electro-magnet, and from which the current passes to
the main current, and the positive carbon. In order to force a part of the main-
current to pass through the branch conducting wire, a metallic resistance of about
1/8 Ohm is interposed in the main current. The electric current is broken when
the sliding-block t is withdrawn from pin by the motion of lever 7. The
antagonistic spring b now draws the armature a away from the electro-magnet, and
at the moment of its farthest distance, the sliding block t is again brought in
contact with pins, thereby closing the current and attracting the armature a. The
current remains closed until the armature has approached nearest to the magnet.
To and fro motion is in this way obtained, developing considerable mechanical
power, which is applied to turn the double screw S S₁. The revolving direction of
the double screw S S¹ and thereby the to and fro motion of the carbon rods is
determined by the regulator which consists of two solenoids, one of which is
influenced by the main current, the other by a derived current. Both Solenoids
tend to attract an iron core F, Fig 5 and 6, (the wire coils aro omitted in the
drawing for the sake of clearness). The iron core F is provided at its under part,
with a pin d which moves the two hook-rods pp¹ by means of the link vand gives
thom a horizontal motion the direction of which depends on the relative influence
of the Solenoids N and N, thereby setting either por pl in gear with wheel R.
According as the wheel R is turned to the right or to the left by the pawls k, k¹
the carbon rods approach each other or go apart. In order to balance the masses,
the core is suspended from the small links n¹ n², whereby the friction is reduced
to a minimum (nothing but the core itself and the two little rods p p' have to be
moved). In order to avoid the continual movement of the armature a under the
influence of the electro-magnet E, a contact-breaker is applied, permitting motion
only, when the sliding of the carbon rods becomes necessary, and one of the
pawls is in gear with the toothed wheel R. For this purpose the core F of the
Solenoid has the function, besides that of a regulator, to control the contact of the
sliding block t with pin which takes place in the following way.
A small shaft w, Fig 1 and 5, adapted to turn on the points of screws y y¹, is
situated at right angles to the core of the Solenoids and is turned a little by the
pin d setting in motion a small crank v when the core moves between the
Solenoids. As shown in Fig 6, the upper half of the shaft w is cut out at the
place where it traverses the contact pin z, which latter is joined or formed into
a frame z¹. On the surface of the flat part wl of shaft w which is insulated with
cbonite stand two little adjusting screws o o¹ screwed into the frame z¹. By the
least turning of shaft w the flat part of w¹ becomes inclined, and lifts one of the
adjusting screws o or o¹ with the frame z¹ and in consequence also the pin z which
then comes in contact with the sliding block t and sets the electro-magnet E in
action which works and moves the carbon rods until the core of the Solenoids is
drawn into its central position, and the plane surface w¹ of the shaft w is horizontal,
whereby the pin & sinks and gets out of contact with sliding block t.
For the caso that one lamp gets out of order, and to prevent the others of the
same electric circuit to do the same, a metallic resistance equal to the resistance of
the arc light, is interposed as follows. Two bobbins A and B standing on a
wooden plate, Fig. 2 and 5, one of which is coiled with thick, the other with thin
wire, which are both continuations of the coils of solenoids N N' and influenced by
the same currents, tend to attract the iron armature X which is pivoted at J and
slightly pressed on the core of B by a small spring f³. If now the carbon rods are too
far apart, so that the main current is interrupted, A loses its attraction, while the
strength of B is augmented and attracts the armature X, leading the main current
through m and a resistance wire to the negative clamp o. The mechanism
continues to work. If the carbon-rods touch each other, the current takes its way
through bobbin A which vigourously attracts the armature and interrupts the
temporary closing of the current through m and the clamp o.
The right and left hand screws S and S¹ may be of the same or of different pitch
according as intermittent or continuous currents are employed.

page_text: CLALIS:
1. The combination of a right and left hand screw S, S₁ or worm formed or
mounted on a common spindle insulated at i and gearing into worm wheels 73, 7%,
for the feed motion of carbon rods of any desired length, the two screws S, S¹
having equal or different pitch, according to the nature of the currents employed
(whether intermittent or continuous).
2. The mechanism for turning the worm wheels 7³ forward or backward, which
comprises an electro-magnet E, armature a, lever h, yoke l, rods p, p² and
pawls k, k², adapted to gear as required either from the right or from the left into
the wheel R provided with a double row of teeth.
"
3. The mechanism for causing the circuit of the electro-magnet E to be closed
during the whole period of the motion of the armature towards the poles, and to
be broken during the whole period of the receding notion of the armature.
4. The mechanism for automatically setting in and out of action the electro-
magnet E, which comprises the core F of the differential solenoid, pin d, shaft w,
insulated facing w', frame c', set screws o, o¹, pin z, and slide block t.
The whole substantially as described and illustrated.
In witness whereof I the said Conrad Wüest have hereunto set my hand and
seal this 22nd day of December A.D. 1883.