A NEW OR IMPROVED ELECTRIC ARC
Year: 1882

page_text: LETTERS PATENT to Lorentz Albert Groth K.G.V Civil Engineer and
Managing Director of The Universal Inventors and Patentees Financial
Company Limited 30 Finsbury Pavement London E.C. for an invention
of "A NEW OR IMPROVED ELECTRIC ARC
"
LAMP Communicated to him
from abroad by Christopher Peter Jürgensen, Professor, of Copenhagen in the
Kingdom of Denmark.
PROVISIONAL SPECIFICATION left by the said Lorentz Albert Groth at
the Office of the Commissioners of Patents on the 17th July 1882.
ول
LORENTZ ALBERT GROTH K.G.V Civil Engineer and Managing Director of
The Universal Inventors and Patentees Financial Company Limited 30 Finsbury
Pavement London E.C. "A NEW OR IMPROVED ELECTRIC ARC LAMP
A com-
munication to me from abroad by Christopher Peter Jürgensen, Professor, of
Copenhagen in the Kingdom of Denmark
The new or improved electric arc lamp forming the subject of this invention is
of the following character
The two carbon holders are respectively supported by two grooved circular discs
or pullies fixed on a common axis carried by the frame work. When either carbon
holder is raised the axis and discs are turned whereby the other carbon holder is
lowered and vice-versa
The carbon holders are guided by suitable bushes in the plate forming the cover
of the case and by solenoids into which they are extended by means of rods of soft
iron. The radii of the above mentioned discs are made proportional to the
lengths of carbon that are burnt away during the same period of time from the
upper and lower carbon points respectively so that the arc is always maintained in
the same place in the lamp. The two solenoids are connected together by biuding
screws, a contact apparatus and the carbon holders.
Before the lamp is connected with the wires a moveable armature in the contact
apparatus will always be held in contact with an adjusting screw in an insulated
carriage by a spiral spring.

page_text: Supposing the carbon points to be so far removed from one another at the
moment when the electrical current is admitted to the apparatus that no luminous
are can be formed between them a part of the current will pass from a binding
screw which for the sake of distinction I shall call + through the insulated
carriage, the adjusting screw, the moveable armature, the insulated carriage for the
same, the outer coils of one of the solenoids to another binding screw which for the
sake of distinction I shall call +,
The upper carbon holder is thereby drawn downwards into the said solenoid
and the lower carbon holder is raised (by the action of the discs as above explained)
until a luminous arc is formed by a branch of the current which then passes
through the first mentioned insulated carriage, the solenoid of an electro magnet to
the upper carbon and thence through the arc, the lower carbon and the solenoid
surrounding that carbon to the binding screw.
As soon as the current has thus branched off the armature is attached by the
beforementioned electro magnet and the current from the insulated carriage of the
said armature to the outer coil of the upper carbon solenoid is broken. The upper
carbon solenoid now only receives a branch of the current which from the moment
the current enters the lamp passes from the binding screw up through the outer
thick coil of the upper carbon solenoid, then through another finer coil, within the
first named back to the binding screw.
The magnetic attraction of the upper carbon holder effected by this branching
of the current counteracts the attraction of the lower carbon holder by the lower
carbon solenoids.
When the luminous arc is weakened by the consumption of the carbon points
the current is also weakened in the lower carbon solenoid, and the current in the
upper carbon solenoid becomes proportionally stronger, consequently the carbon
points approach one another till the normal condition of the currents in the
solenoids is reestablished. When the luminous are becomes shortened from any
cause the current in the lower carbon solenoid becomes stronger while that in the
upper carbon solenoid becomes weaker and the carbon points will be separated
further apart. In order to regulate or reduce the movements of the carbon holders
so that no objectionable unsteadiness of the light shall occur one of the carbon
points is connected with the piston rod of a hydraulic brake. To enable the lamp
to be used with currents of different tension the axis of the discs is connected by a
toothed pinion and wheel with an enclosed spring. By regulating the tension of
this spring as required the said axis can be balanced to suit any particular case.
The lamp may be arranged so as to hang down but in that case the mechanism
must be so adapted that the carbon points are placed below.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Lorentz Albert Groth in the Great Seal Patent Office on the
17th January 1883.
A com-
LORENTZ ALBERT GROTH, K.G.V. Civil Engineer, and Managing Director of
The Universal Inventors and Patentees Financial Company Limited, 30 Finsbury
Pavement London E.C. "A NEW OR IMPROVED ELECTRIC ARC LAMP"
munication to me from abroad by Christopher Peter Jürgensen, Professor, of
Copenhagen, in the Kingdom of Denmark.
The new or improved electric arc lamp forming the
illustrated in the drawings hereto annexed, in which
figures 2 and 3 elevations of details and figure 4
arrangements
subject of this invention is
figure 1 is a side elevation,
a diagramatic view of the
The two carbon holders K¹ and K are respectively supported by two grooved
circular discs or pullies and H fixed on a common axis X carried by the frame
work. When either carbon holder is raised the axis X and discs are turned
whereby the other carbon holder is lowered, and vice versa.
The carbon holders are guided by suitable bushes in the plate C₁ forming the
cover of the case g and by the solenoids S'and S into which they are extended
by means of rods of soft iron. The radii of the above mentioned discs H and h
are made proportionate to the lengths of carbon that are burnt away during the
same period of time from the upper and lower carbon points respectively, so that
the arc is always maintained in the same place in the lamp.
The two solenoids S¹ and S are connected together by the binding screws p
and pa contact apparatus R and the carbon holders K and K as shown in
figure 4.
Before the lamp is connected with the wires a moveable armature A in the
contact apparatus R (figures 3 and 4) will always be held in contact with an
adjusting screw b in an insulated carriage O by a spiral' spring attached to the
carriage y.
Supposing the carbon points to be so far removed from one another at the
moment when the electrical current is admitted to the apparatus that no luminous
arc can be formed between them, a part of the current will pass from a binding
screw through the insulated carriage O the adjusting screw b, the moveable
armature A, the insulated carriage V, the outer coils of the wire s in the solenoid S
to another binding screw p÷. The upper carbon holder K is thereby drawn
downwards into the said solenoid S and the lower carbon holder K¹ is raised to
the action of the discs H, h, as above explained, until a luminous are is formed by
a branch of the current which then passes through the first mentioned insulated
carriage O, the solenoid of an electro-magnet m to the upper carbon and thence
through the arc, the lower carbon and the solenoid S¹ surrounding that carbon to
the binding screw p→
As soon as the current has thus branched off the armature A is attached by the
before mentioned electro magnet M and the current from the insulated carriage V
of the said armature to the outer coils of the upper carbon solenoid S is broken.
The upper carbon solenoid S now only receives a branch of the current which
from the moment the current enters the lamp passes from the binding screw p÷
up through the outer coil 8 of the upper carbon solenoid S then through finer
coil 8 within the first named back to the binding screw p+.
The magnetic attraction of the upper carbon holder K effected by this branching
of the current counteracts the attraction of the lower carbon holder K³, by the
lower carbon solenoid S'.

page_text: When the luminous arc is weakened by the consumption of the carbon points
the current is also weakened in the lower carbon solenoid S₁ and the current in
the upper carbon solenoid S becomes proportionally stronger, consequently the
carbon points approach one another till the normal conditions of the currents in the
solenoids is reestablished.
When the luminous are becomes shortened from any cause the current in the
lower carbon solenoid S' becomes stronger while that in the upper carbon
solenoid S becomes weaker and the carbon points will be separated further apart.
In order to regulate or reduce the movements of the carbon holders so that no
objectionable unsteadiness of the light shall occur, one of the carbon points is
connected with the piston rod of a hydraulic brake K. To enable the lamp to be
used with currents of different tension the axis ✗ of the discs is connected by a
toothed pinion d and wheel d' with an enclosed spring F.
By regulating the tension of this spring as required the said. axis X can be
balanced to suit any particular case:
The lamp may be arranged so as to hang down but in that case the mechanism
must be so adapted that the carbon points are placed below.
Having now described the nature of the said invention and. the manner in
which the same is to or may be carried into effect, I would have it understood that
what I claim is
The use of two solenoids S and S¹ each working direct on their respective carbon
holders K and K'.
In witness whereof I the said Lorentz Albert Groth have hereunto set my
hand and seal this thirteenth day of January A.D. One thousand eight
hundred and eighty three.
LORENTZ ALBERT GROTH (L.S.)