IMPROVEMENTS IN APPARATUS FOR THE DYNAMICAL PRODUCTION AND APPLICATION OF ELECTRICITY, AND FOR ITS REGULATION WHEN APPLIED FOR ILLUMINATION
Year: 1878

page_text: "
the Invention, of." IMPROVEMENTS IN APPARATUS FOR THE DYNAMICAL
PRODUCTION AND APPLICATION OF ELECTRICITY, AND FOR ITS REGULATION
WHEN APPLIED FOR ILLUMINATION A communication from Abroad by
Ernst Werner Siemens and Friedrich Hefner von Alteneck both of Berlin,
in the German Empire, bearing date the 8th day of August, 1878
N° 3134.
DISCLAIMER AND MEMORANDUM OF ALTERATION as proposed to be
entered by the said Carl Heinrich Siemens pursuant to the Statutes in that
case made and provided.
WHEREAS Her Majesty Queen Victoria by Her Letters Patent under the Great
Seal of the United Kingdom of Great Britain and Ireland, bearing date at West-
minster the eighth day of August 1878 N° 3134, in the forty-second year of Her
Reign, did give and grant unto the said Carl Heinrich Siemens his executors
administrators and assigns, the sole privilege, for the term of fourteen years, thence
next ensuing, of making, using, exercising, and vending within the United Kingdom
of Great Britain and Ireland, the Channel Islands and the Isle of Man the said
invention of "Improvements in apparatus for the Dynamical production and
application of electricity, and for its regulation when applied for Illumination a
communication from Abroad by Ernst Werner Siemens and Friedrich Hefner von
Alteneck, both of Berlin in the German Empire.
17
And whereas in pursuance of a proviso in the said Letters Patent contained, the
said Carl Heinrich Siemens did within Six Calendar Months next after the date
of the said Letters Patent cause a Specification or Instrument in writing under his
hand and seal, purporting to describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, to be duly filed in the Great
Seal Patent Office.

page_text: shown
A
present invention, arranged so as to increase the electro-motive force of the currents
generated. For this purpose the coils are arranged and connected as I will describe
with reference to Figs. 1, 2, 3 and on Sheet I of the accompanying Drawings.
Figure 1 is a plan of the machine, Figure 2 is an end view shewing the arrange-
5:ment of the commutator brushes, Figure 3 is a diagrammatic front view shewing
the connections of the brushes to the coils of the electro-magnets, and Figure 4 is a
diagrammatic end view of the cylindrical armature shewing the connections of its
coils to the plates of the commutator. In these Figures there are
28 coils or.
bundles of insulated wires extending lengthwise of the armature D in the .28.
divisions of its circumference, and the coinmutator C has 28 insulated plates to
correspond. There may, however, be another even number of coils and commutator,
plates, and the number of brushes E and F for collecting the electricity from the
commutator plates, instead of being 12 on each side as shewn, may be more or less..
Each pair of opposite divisions of the armature, such as 1 and 15, 2 and 14, and so
on, is coiled with two separate wires, each wound lengthwise along one division,
across the end, then along the opposite division, across the other end, and so on, one
of the wires starting from an insulated metallic ring a which is fixed at one end of
the armature, and terminating in one of the commutator plates, the other wire.
starting from the opposite commutator plate and terminating in the same ring a
which thus receives ends of all the wires. The two sets of brushes E and F extend.
tangentially each over a considerable portion of the circumference of the com-
mutator, bringing a number of its plates simultaneously into connection with the
circuit of the machine. All the brushes E of the one set are in metallic connection
with a junction E whence the currents collected pass in parallel circuit through
the right hand coils of the electro-magnets A and B, meeting again at E²
where they are connected to the external circuit. In like manner the currents
from the other set of brushes F of opposite direction, are all connected.
through the junction F and parallel through the left hand coils of the electro
magnets to the junction F2 and thence to the external circuit. In a inodified
form of the apparatus the revolving armature instead of being made, in the
shape of a long cylinder, is a flat ring which may be of soft iron, solid or made
up of iron wires or hoops or annular laminæ secured together, the electro magnets
being cylindrical cores wound with insulated wires and presenting their ends to.
the sides of the coiled ring. This construction, to which I inake no claim, is shewn
in Sheet II of the accompanying drawings, Figure 1 being a longitudinal section,
and Figure 2 a front view with part of the framing and electro-magnets supposed
to be removed in order to shew part of the ring armature and its coils
beyond. On a base A are fixed the two end frames B; B, to each of.
which are secured a number of electro-magnets C (of which 8 pairs are
shewn in these Figures) their coiled cores projecting inwards parallel to the
axis of the machine, and terminating in iron plates F of trapezoidal shape
forming polar fields. On the shaft E which is mounted in bearings in the end
frames B, B, is fixed a boss J from which project a number of forked arms each
embracing the ring D. On the ring are wound transversely insulated wires, each
forming a coil S which by revolution of the axis E is caused to pass the
uccessive polar fields of the electro magnets C, C, on each side of it. The coils of
hese magnets are so connected that the two polar fields facing each other are
lways of the same polarity, the next two in order being of the opposite polarity,
nd thus the coils in passing through the successive fields have alternating
lectrical currents induced through them. These currents may be transmitted
eparately from the machine, or combined in pairs or other groupings, for which
urpose a number of insulated rings H (of which four are shewn in the Figures).
re fixed on the axis E with contact brushes K bearing tangentially against themn.
The several coils S having their wires connected to these rings, as for instance two
oils to each ring, the currents induced in them are collected by the brushes K and
ay be commutated in usual way. As the electro-magnets C have .constant
the
6
the
A
:

page_text: polarity, their coils are connected with the contact brushes K of a commutator &
fixed on the end of the shaft E, that commutator having a number of insulated
plates corresponding with the number of pairs of electro-magnets, or the equal
number of coils S. "It is to be understood that these numbers may be varied, and
that
A
the number of coils S, instead of being the same as that of the pairs of electro- 5
magnets C, may be a multiple of that number, the collecting rings H and plates of
the commutator G being varied accordingly. The ring D as above mentioned may
be of soft iron solid. It is preferred, however, in order to increase rapidity of,
induction, to construct it of iron wires, or hoops, or lamina, which, in order to avoid
internal inductive currents, should be insulated from each other by a coating of 1
oxide or varnish or by fibre spun on them. The coils S wound on the ring are
preferably double, as in the machine described with reference to Sheet I of the
accompanying Drawings.
According to a modified construction of this machine the electro-magnets face.
each other as in the machine last described but with opposite polarity, and between
them rotates a disc carrying a number of coils of wire wound in the plane of the
disc, which as well as the cores of the coils is of non magnetic. material. This
construction is shewn in Sheet III of the accompanying Drawings, Figure 1 being
a longitudinal section of the machine, and Figure 2 a front view. On the base A
are fixed the two side frames B, carrying each a number of electro-magnets C, O, (of
which 16 are shewn in the Drawings) and bearings for the shaft E. On this shaft
is fixed a disc J carrying a number of coils S of elongated shape, as shewn by the
dotted lines in Figure 2. These coils are wound in the plane of the disc on cores
D of elongated shape and preferably of wood. The electro-magnets C have their
facing polar ends extended as before described, by fixing on them trapezoidal iron
plates F, and these plates and the coils S are so proportioned that each coil has
advanced over about half the width of each plate, while it still faces about half the
width of the plate from which it is retreating. The collection of the currents,
induced in the coils S by their passage through the magnetic fields of alternating
polarity, and the combination and commutation of these currents, and of such
portions of them as may be employed for exciting the electro magnets C are effected
in the usual way by contact rings H and the commutator G provided with
tangential contact brushes as already described.
The electro-magnets instead of being placed with their cores parallel to the
shaft of the machine may be placed radially, the coils of the revolving armature.
being wound on a cylindrical shell which revolves between an inner and an outer
set of radiating electro-magnets. This construction is shewn in Sheet IV of the
accompanying Drawings. Figure 1 is a longitudinal section of the machine and
Figure 2 a front view partly in section, Figures 3, 4, and 5 shew details as to the
winding of the coils as will be explained. On the base A is secured a ring frame B,
from which project a number of electro-magnets C radially inwards. The frame
also carries a hollow boss B' from which project a corresponding number (12 shewn
in the Drawings) of electro-magnets C' projecting radially outwards. Both sets of
magnets have their cores terminating in iron plates F and F, respectively concave
and convex, so as to present between them a narrow annular space. In this space
revolves the cylindrical shell D containing the coils S, the shell being fixed to a
disc J carried by the shaft E. The coils S are wound on wooden or non-magnetic
cores D of elongated form, as shewn in Figure 3 being connected as shewn in the
Figure with their convolutions alternately in opposite directions. Each pair of
magnets C and C¹ facing each other present opposite polarity. The coils S may
be duplicated, as shewn in Figures 4 and 5, one set of coils facing the inner magnets
and the other set facing the outer magnets, and those of the one set extending half
way over those of the other set. In this machine the collection and commutation
of the induced currents are effected by contact rings, commutators and tangent
brushes as already described. The machines described with reference to the
Figures in Sheets II, III and IV of the accompanying Drawings may obviously be
arranged. in an inverted manner, that is, to say, the, electro-magnets might be mad

page_text: to revolve round a stationary coiled armature. Also the machines described as
well.as that shewn in Sheet I, instead of being driven by mechanical power so as
to generate electricity, may be made to give out mechanical power by exciting
their coils by electricity from an external source.
For the production of small electro-motive force to act in circuits of small resist-
ance, as for example those presented in galvanic decomposition, apparatus is some-
times employed depending for its action on the known principle that when a metal
cylinder rotates round the cylindrical pole of a magnet there is an electro-motive force
tending to produce in the rotating cylinder a current parallel to the axis of rotation.
In order to increase such currents and render them practically serviceable, apparatus
of this kind is according to the present invention arranged as shewn in Sheet V of
the accompanying drawings. Figure 1 is a front view shewing half in elevation
and half in vertical section, and Figure 2 is a sectional plan. Two cores A and A'
secured to a base plate 'B, all of soft iron form a horse-shoe magnet. Each core is
surrounded by a cylindricall copper shell C secured to an axis d, on which is a
pinion e gearing with a wheel, so that when this wheel is caused to revolve the
shells C revolve round the cores A A' without touching them. Outside the
sheels C but not touching them are cylindrical iron shells ff, secured to a plate f
and with it forming a horse-shoe magnet. The cores A A' are at their lower
parts surrounded by helices g g' of thick copper, and similar helices h h¹ surround
the upper parts of ff. These helices are put in electrical connection with the
shells C in the following manner. A shallow vessel k containing mercury has
revolving in it a disc attached to the shell C which by centrifugal force causes the
mercury to gather towards the periphery making contact between, the disc and the
vessel, and in like manner contact is made in a shallow vessel at the top and thus
when the shells Care caused to rotate an electrical current is created which is led
to the external circuit by the terminals m m'. The helices h h on the shells ff
may be dispensed with, the shells in that case being connected throughout their
length by iron, so that they form an armature for the lower magnet A, B, A¹.
The apparatus may be employed electro-dynamically by sending an electric
current through it and thus causing rotation of the shells C. For the soft iron
magnets with helices, permanent magnets may be employed. From the construction
above described it will be seen that the shells C-C, being caused to rotate in an
extensive and powerful magnetic field, there is considerably. greater production of
electricity than when there is only a disc or cylinder rotating round the pole end
of a magnet as in machines hitherto known which act on the like principle.
Farther, by using a mercury contact as above described, there is comparatively little
resistance to rotation, and by making the machine excite its own magnets, they
become charged to their maximum power.
Having thus described the nature of the said invention and in what manner
the same is to be performed, as communicated to me by my foreign correspondents,
I claim-
the
A
First. In a machine constructed according to Specification N° 2006 of the
year 1873, connecting the duplicate coils of the revolving armature respectively to
the opposite plates of the commutator, and to a metal ring common to all the coils,
and transmitting the currents induced in these coils through numerous tangential
brushes to the coils of the electro-magnets in parallel connection, as herein described
with reference to the Figures on Sheet I of the accompanying drawings.
Second. The construction of a dynamo electric or electro-dynamic machine
wherein for the coiled iron ring shewn in Sheet II of the Drawings, which ring is
caused to revolve between the poles of electro-magnets arranged in circular order
with their cores parallel to the axis of the machine and terminating in iron plates
forming extended polar fields facing the coils of the ring, there is substituted a disc
of non-magnetic material carrying coils of insulated wire wound in the plane of
the disc, substantially as herein described with reference to the Figures in Sheet III
of the accompanying drawings.

page_text: '
Third. The construction of a dynamo-electric or electro-dynamic machine wherein
for the disc referred to in the preceding claim there is substituted a cylindrical
shell carrying coils, and revolving between the poles of interior and exterior
radiating electro-magnets, substantially as herein described with reference to the
Figures in Sheet IV of the accompanying drawings.
Fourth. The construction of a dynamo-electric or electro-dynamic machine,
wherein cylindrical shells of copper rotate around and within cylindrical limbs of
electro-magnets, contacts for the electrical currents through the rotating shells being
effected by mercury contained in shallow vessels within which rotate discs attached
to the shells or their axes, substantially as herein described with reference to the
Figures in sheet V of the accompanying drawings.
In witness whereof I the said Carl Heinrich Siemens have hereunto set my
hand and seal this Fourth day of February in the year of our Lord One thousand
eight hundred and seventy nine.
CARL HEINRICH SIEMENS (L.S.)
In Witness whereof I the said Carl Heinrich Siemens have hereunto set my
hand and seal this Eighteenth day of August in the year of our Lord One thousand
Witness.
DR GUSTAVE PRÖLLZ
To the Commissioners of Patents for Inventions
Notice of the application for leave to file this Disclaimer having been advertized
as required by me :-
I bereby grant my Fiat giving leave to the above named Carl Heinrich
Siemens to tile in the Office of the Commissioners of Patents for Inventions
with the Specification to which the same relates the foregoing Disclaimer and
Memorandum of Alteration.
1000
Notice of the application for leave to file this Disclaimer having been advertized
as required by me :-
I hereby grant my Fiat giving leave to the above named Carl Heinrich
Siemens to tile in the Office of the Commissioners of Patents for Inventions
with the Specification to which the same relates the foregoing Disclaimer and
Memorandum of Alteration.
1000

page_text: LETTERS PATENT to Carl Heinrich Siemens, of No. 12, Queen Anne's Gate,
Westminster, in the County of Middlesex, for the Invention of "IMPROVEMENTS
IN APPARATUS FOR THE DYNAMICAL PRODUCTION AND APPLICATION OF ELEC-
TRICITY, AND FOR ITS REGULATION WHEN APPLIED FOR ILLUMINATION." A
communication from abroad by Ernst Werner Siemens and Friedrich Hefner
von Alteneck, both of Berlin, in the German Empire
PROVISIONAL SPECIFICATION left by the said Carl Heinrich Siemens at
the Office of the Commissioners of Patents on the 8th August 1878.
CARL HEINRICH SIEMENS, of No. 12, Queen Anne's Gate, Westminster, in the
County of Middlesex. "IMPROVEMENTS IN APPARATUS FOR THE DYNAMICAL
PRODUCTION AND APPLICATION OF ELECTRICITY, AND FOR ITS REGULATION WHEN:
APPLIED FOR ILLUMINATION." [A communication from abroad by Ernst Werner
Siemens and Friedrich Hefner von Alteneck, both of Berlin, in the German
Empire.]
Apparatus known as dynamo-electric apparatus are employed for the conversion
of mechanical power into electricity, that is to say, for the production of electrical
currents when mechanical force is applied to work the apparatus.
The electricity produced by the working of such apparatus, like that produced.
from other sources, can be applied for chemical decomposition or other purposes, and
can also be applied in apparatus similar to that which produced it for the production -
of motive power (in which case the apparatus is said to act as electro-dynamic.
apparatus); or under proper regulation it may be applied to the production of
electric light by causing it to pass from one carbon point to another.
୮

page_text: This Invention relates to apparatus applicable as dynamo-electric apparatus for
the conversion of mechanical power into electricity, or as electro-dynamic apparatus
for the application of electricity to produce motive power, and also to apparatus for
the application of electricity to purposes of illumination.
In the Specification to Letters Patent "granted to C. W. Siemens on the 5th June
1873, No. 2006, was described dynamo-electric apparatus in which a cylindrical
armature wound longitudinally with coils of insulated wire revolves in the polar
fields of electro-magnets.
Instead of arranging the armature coils as described in the said Specification so
as to form separate closed circuits brought successively into connection with the 1
coils of the electro-magnets, they are, according to the present Invention, arranged
so as to increase the electro-motive force of the currents generated. For this
purpose the wires of all the armature coils start from a single metallic ring fixed on
the armature, and each wire terminates in a separate insulated plate of a commu-
tator, all these plates being fixed on the axis of the armature and revolving with it.
Two sets of metallic brushes or rollers bearing against the plates of the commutator
collect and combine the electric currents successively generated in the coils by their
passage through the magnetic fields, and the currents so combined are led in parallel
direction through the coils of the electro-magnets to the terminals of the apparatus,
and thence through the external circuit.
In a modified form of the apparatus the armature instead of being made in the
shape of a long cylinder is a flat ring, which may be of solid soft iron or made up
of iron wires or hoops or annular lamina secured together. This ring armature is
carried by forked arms projecting from a central boss on the shaft of the machine,
and between each pair of the supporting arms or spokes is a coil of insulated wire
wound on the ring transversely. The wires of these coils, as in the former case, all
start from one metallic ring, and each terminates in one of the insulated plates of
the rotating commutator fixed on the shaft of the machine. The electro-magnets
in this form of apparatus are coiled cores projecting from the two side frames of the
machine parallel to its axis, each core terminating in a soft iron segment approaching
closely to but not actually touching the coiled ring armature which revolves between
the segments thus arranged on each side of it.
The coils of the electro-magnets are so wound and connected that each pair of
the segments facing each other on opposite sides of the armature are of similar
polarity, and the next pair in order are of the opposite polarity. When the ring is
caused to rotate each of its coils is thus made to pass through successive fields of
alternately opposite polarity, whereby alternating electrical currents are generated
in each of the coils. These currents instead of being combined by a commutator
may be transmitted separately as alternating currents, or those of each two or more
of the coils may be combined together, for which purpose a number of insulated
metallic rings are fixed on the shaft of the machine, and the wires of the coils are
connected either separately or in pairs or other groupings to these rings, to which
are applied contact brushes or rollers as to a commutator.
According to a modified construction of this machine the electro-magnets facing
each other are of opposite polarity, and between them rotates the disc carrying a
number of coils of wire wound in the plane of the disc, which, as well as the cores.
of the coils, is of non-magnetic material. The electro-magnets instead of being
placed with their cores parallel to the shaft may be placed radially, and in this case
instead of a disc carrying coils a cylindrical shell of non-magnetic material carries
the coils which are wound alternately in opposite directions on short radial cores of
non-magnetic material. This cylindrical shell with its coils revolves outside the
poles of the inner radial electro-magnets.
For the production of small electro-motive force to act in circuits of small
resistance, as, for example, those presented in galvanic decomposition, apparatus is
sometimes employed which depends for its action on the well-known principle that
when a metal cylinder rotates round the cylindrical pole of a magnet there is an

page_text: electro-motive force tending to produce in the rotating cylinder a current parallel
to the axis of rotation.
In order to increase such currents and render them practically serviceable appa-
ratus of this kind is, according to the present Invention, arranged in the following
manner: Two iron cores project from a bar, and from another bar facing the
former two iron tubes project, each tube enclosing within it one of the before-
mentioned cores with an annular space between the exterior of the core and the
interior of the tube. In this annular space is introduced a hollow cylinder of
copper attached to a spindle passing through the second bar. The two spindles are
connected by gearing, so that they, with the copper cylinders attached to them, can
be caused to revolve in the same direction, the copper cylinder nearly fitting to but
not actually rubbing the surfaces of the tube and core. At the one end of the
copper cylinder is fixed a disc-shaped collar which revolves within a shallow cavity
formed in an insulated casing attached to the iron core; and in like manner on the
spindle of each copper cylinder is fixed a disc collar revolving in a shallow cavity
of another insulated casing. A little mercury introduced into those casings forms
the electrical connection between the ends of the copper cylinders and the casings
respectively, and from the casings conducting wires can lead the generated currents
as desired. The cores with their connecting bar, also the tubes with their connecting
bars, may be permanent magnets, or they may be electro-magnets rendered active
by the currents generated in the machine itself, for which purpose both the cores
and the tubes have on them a few turns of copper bar wound helically, the copper
bars being in electrical connection with the before-mentioned casings.
This apparatus, when the copper cylinders are caused to revolve by mechanical
force, generates electrical currents, or when electricity from, an extraneous source
is conducted to it, the copper cylinders are caused to revolve.
In dynamo-electric machines as usually constructed the currents developed in the
moving armature coils are conducted through the coils of the electro-magnets in
presence of which the armature coils move, and increase in their magnetic force cause
more powerful currents to be developed in the armature coils, which farther increase
the magnetism until a certain limit of magnetic force is attained.
According to the present Invention this system is modified so as to produce a
chain of dynamo-electric action in the following manner :-The currents produced
in the coils of one armature are led to the electro-magnets of a second armature,
and the currents produced in the coils of this second armature are led to the electro-
magnets of a third, and so on through a series of successive elements, the last or any
intermediate one of which may be connected to the electro-magnets of the first. A
chain consisting of several elements may be branched off into two or more continued
chains of like character, or several chains of elements may coalesce into one chain.
Also each element may receive its electricity partly from other elements of the chain
and partly from its own armature.
Although in what has preceded the apparatus has been mostly described as of
the dynamo-electric kind, whereby mechanical power applied to drive them is con-
verted into electricity, it is to be understood that with suitable modifications these
apparatus are generally applicable also as electro-dynamic machines, their rotary parts
being caused to revolve and give out mechanical power when electricity is applied
to them, and thus one of these machines may be driven by any suitable motive
power so as to generate electricity, and this electricity may be conducted to a similar
imachine at a distance, causing it to work and to give out a portion of the power
applied in the first instance.
Also the electric currents generated by such dynamo-electric machines as have
been described may be applied to produce electric lights in electric lamps of any
known construction, and also in lamps which will now be described, but which, it
is to be understood, may be worked likewise by electricity generated by machines
of different construction or produced from other known sources of electricity.
In applying electricity for illumination by causing electric currents of constant or

page_text: -alternating polarity to pass from one carbon point to another; there are considerable
practical difficulties in effecting the delicate adjustment of the distance between
the carbons and in maintaining that adjustment while the carbons themselves are
'consumed.
In order to effect and maintain this adjustment automatically when alternating
electrical currents are employed, a lamp is, according to this Invention, constructed
as follows:-Two carbon rods are at their lower ends held some distance apart in
sockets mounted on joints or springs in such a manner that the upper ends of the
"carbons are made to lean against each other in the attitude of the two limbs of an
'inverted V. Between the two carbons is an upright rod of insulating or badly
conducting refractory material, the lower end of which is inserted in or attached to
'a piece of soft iron. The iron is free to slide vertically within a tubular coil of
insulated wire, which is in the electric circuit of the carbons.
$
When currents of electricity pass through the coil and the carbons, the coil being
rendered magnetic attracts the iron upwards, and the refractory rod attached to the
iron is thus thrust between the upper ends of the carbons, tending to separate them.
If it should separate them so far that the electric currents cease to pass from the
one to the other, then the currents through the coil being also arrested, the attraction
of the iron ceases, and the iron thereupon descends, withdrawing the refractory rod,
and so allowing the carbons again to approach each other. As the carbons consume
away the refractory rod consumes with them.
The automatic adjustment of the carbons can also be effected by giving to either
or both of the carbons an oscillating movement of alternate approach to and recession
from each other, the combination with a continuous approach or feeding movement
'as the carbons are consumed.
When either constant or alternating currents are employed the oscillating move-
ment may be produced by clockwork or other suitable motor, but when the lamp
is worked only by alternating currents it is more advantageous to effect the
oscillation by the electro-magnetic action of the currents themselves, the continuous
'feeding movement being produced by the action of a weight or spring, or of a float,
as will now be described."
In one form of lamp arranged to act in this manner the upper carbon rod is
guided between rollers making electrical contact with it, but giving it sufficient
freedom to descend by gravity: The lower carbon is connected to the spring
'armature of an electro-magnet, having its coils in the circuit of the carbons. The
electric currents cause the armature and the lower carbon to vibrate rapidly through
a short vertical stroke, and as the carbons are consumed the upper carbon slides
down towards the lower carbon. Owing to the rapidity of the vibrations and the
inertia of the upper carbons the contacts of the carbon points are for instants
alternating with intervals of separation during which the light is produced, the
recurrence of these intervals being so rapid as to give a practically continuous
light.
According to a modified arrangement the lower carbon is stationary, and the
upper carbon is fitted to slide with a small amount of friction produced by the
lateral pressure of a light spring through eyes or a socket connected to the vibrating
armature, so that the upper carbon is made to oscillate and also gradually descends
as the carbons are consumed.
· The upper carbon may be fixed to the armature so as to oscillate without
descending, the lower carbon being pressed gradually upwards by attaching it to a
floating mercury.
Instead of employing an electro-magnet with a spring armature to produce the
oscillations, the carbon may be attached to the end of an elastic helical wire
surrounding a fixed iron core. By the passage of alternating currents through the
helical wire it is caused to vibrate longitudinally, and its vibrations are imparted to
the carbon attached to it.
The carbons instead of being arranged in line with one another may be set so as

page_text: to lean against each other at their points, being separated at their bases like the
limbs of an inverted V. One of these carbons may be stationary, the other being
caused to vibrate and also to be pressed towards it by its own weight or by a float;
or the one carbon may be made to vibrate while the other is continuously pressed
towards it.
Lamps arranged as above described can be introduced in numbers into a single
circuit without interfering with one another, and without the extinction of one
producing more than a momentary interruption, as each is kindled by the simple
passage of the electric current through its carbons; and if extinguished by a
momentary separation or contact of its carbons becomes at once rekindled by their
immediate approach or recession.

page_text: SPECIFICATION in pursuance of the conditions of the Letters. Patent filed by
the said Carl Heinrich Siemens in the Great Seal Patent Office on the 7th
February 1879.
CARL HEINRICH SIEMENS, of No. 12, Queen Anne's Gate, Westminster, in the
County of Middlesex. "IMPROVEMENTS IN APPARATUS FOR THE DYNAMICAL
PRODUCTION AND APPLICATION OF ELECTRICITY, AND FOR ITS REGULATION WHEN
APPLIED FOR ILLUMINATION." A communication from abroad by Ernst Werner
Siemens and Friedrich Hefner von Alteneck, both of Berlin, in the German
Empire.
Apparatus known as dynamo-electric apparatus are employed for the conversion
of mechanical power into electricity, that is to say, for the production of electric
currents when mechanical force is applied to work the apparatus.
The electricity produced by the working of such apparatus, like that produced
from other sources, can be applied for chemical decomposition or other purposes, and
can also be applied in apparatus similar to those which produce it for the production
of motive power (in which case the apparatus is said to act as electro-dynamic
apparatus) or under proper regulation it may be applied to the production of electric
light by causing it to pass from one carbon point to another.
This Invention relates to apparatus applicable as dynamo-electric apparatus for
the conversion of mechanical power into electricity, or as electro-dynamic apparatus
for the application of electricity to produce motive power, and also to apparatus for
the application of electricity to purposes of illumination.
In the Specification to Letters Patent granted to C. W. Siemens on the 5th of June
1873, No. 2006, was described dynamo-electric apparatus in which a cylindrical
armature wound longitudinally with coils of insulated wire revolves in the polar
fields of electro-magnets.
Instead of arranging the armature coils as described in the said Specification so
as to form separate closed circuits brought successively into connection with the
coils of the electro-magnets, they are according to the present Invention arranged
so as to increase the electro-motive force of the currents generated. For this
purpose the coils are arranged and connected as I will describe with reference to
Figures 1, 2, 3, and 4 on Sheet I. of the accompanying Drawings.
Figure 1 is a plan of the machine; Figure 2 is an end view shewing the arrange-
ment of the commutator brushes; Figure 3 is a diagrammatic front view shewing
the connections of the brushes to the coils of the electro-magnets; and Figure 4 is
a diagrammatic end view of the cylindrical armature shewing the connections of
its coils to the plates of the commutator. In these Figures there are shewn 28 coils
or bundles of insulated wires extending lengthwise of the armature D in the
28 divisions of its circumference, and the commutator C has 28 insulated plates to
correspond. There may, however, be another even number of coils and commutator
plates, and the number of brushes E and F for collecting the electricity from the
commutator plates, instead of being 12 on each side as shewn, may be more or less.
Each pair of opposite divisions of the armature, such as 1 and 15, 2 and 14, and so
on is coiled with two separate wires each wound lengthwise along one division
across the end, then along the opposite division across the other end, and so on, one
of the wires starting from an insulated metallic ring a which is fixed at one end of
the armature and terminating in one of the commutator plates, the other wire
starting from the opposite commutator plate and terminating in the same ring a,
which thus receives ends of all the wires. The two sets of brushes E and F extend
tangentially each over a considerable portion of the circumference of the commutator,
bringing a number of its plates simultaneously into connection with the circuit of
the machine. All the brushes E of the one set are in metallic connection with a
junction E', whence the currents collected pass in parallel circuit through the right-
hand coils of the electro-magnets A and B, meeting again at E2 where they are

page_text: connected to the external circuit. In like manner the currents from the other set
of brushes F, of opposite directions, are all connected through the junction F' and
parallel through the left-hand coils of the electro-magnets to the junction F, and
thence to the external circuit.
In a modified form of the apparatus the revolving armature, instead of being made
in the shape of a long cylinder, is a flat ring which may be of soft iron, solid or made
up of iron wires or hoops or annular laminæ secured together, the electro-magnets
being cylindrical cores wound with insulating wires and presenting their ends to
the sides of the coiled ring.
This construction is shewn in Sheet II. of the accompanying Drawings, Figure 1
being a longitudinal section, and Figure 2 a front view with part of the framing
and electro-magnets supposed to be removed in order to shew part of the ring
armature and its coils beyond. On a base A are fixed the two end frames B, B, to
each of which are secured a number of electro-magnets C (of which 8 are shewn in
these Figures) their coiled cores projecting inwards parallel to the axis of the
machine, and terminating in iron plates F of tapezoidal shape forming polar fields.
On the shaft E, which is mounted in bearings in the end frames B, B, is fixed a boss
J from which project a number of forked arms, each embracing the ring D. On the
ring are wound transversely insulated wires, each forming a coil S, which by the
revolution of the axis E is caused to pass the successive polar fields of the electro-
magnets C, C, on each side of it. The coils of these magnets are so connected that
the two polar fields facing each other are always of the same polarity, the next two
in order being of the opposite polarity, and thus the coils S in passing through the
successive fields have alternating electrical currents induced through them.
J
These currents may be transmitted separately from the machine, or combined in
pairs or other groupings, for which purpose a number of insulated rings H (of which
four are shewn in the Figures) are fixed on the axis E with contact brushes K
bearing tangentically against them. The several coils S having their wires connected
to these rings, as for instance two coils to each ring, the currents induced in them
are collected by the brushes K and may be commutated in the usual way. As the
electro-magnets C have constant polarity their coils are connected with the contact
brushes K of a commutator G fixed on the end of the shaft E, that commutator
having a number of insulated plates corresponding with the number of pairs of
électro-magnets or the equal number of coils S.
It is to be understood that these numbers may be varied, and that the number of
coils S, instead of being the same as that of the pairs of electro-magnets C, may be
a multiple of that number, the collecting rings H and plates of the commutator G
being varied accordingly.
The ring D, as above mentioned, may be of soft iron, solid. It is preferred,
however, in order to increase rapidity of induction, to construct it of iron wires, or
hoops, or laminæ, which in order to avoid internal inductive currents should be
insulated from each other by a coating of oxide or varnish, or by fibre spun on
them. The coils S wound on the ring are preferably double, as in the machine
described with reference to Sheet I. of the accompanying Drawings.
According to a modified construction of this machine the electro-magnets face
each other, as in the machine last described, and between them rotates a disc
carrying a number of coils of wire wound in the plane of the disc, which, as well
as the cores of the coils, is of non-magnetic material. This construction is shewn
in Sheet III. of the accompanying Drawings, Figure 1 being a longitudinal section of
the machine, and Figure 2 a front view. On the base A are fixed the two side
frames B, carrying each a number of electro-magnets C, C, (of which 16 are shewn
in the Drawings), and bearings for the shaft E. On this shaft is fixed a disc J,
carrying a number of coils S of elongated shape, as shewn by the dotted lines in
Figure 2. These coils are wound in the plane of the disc or cores D of elongated
shape, and preferably of wood. The electro-magnets C have their facing polar ends
extended, as before described, by fixing on them tapezoidal iron plates F, and these
plates and the coils S are so proportioned that each coil has advanced over about

page_text: half the width of each plate, while it still faces about half the width of the
plate from which it is retreating. The collection of the currents induced in the
coils S by their passage through the magnetic fields of alternating polarity, and the
combination and commutation of these currents, and of such portions of them as
may be employed for exciting the electro-magnets C, is effected in the usual way by
contact rings H and the commutator G, provided with tangential contact brushes,
as already described.
The electro-magnets, instead of being placed with their cores parallel to the shaft
of the machine, may be placed radially, the coils of the revolving armature being
wound on a cylindrical shell which revolves between an inner and an outer set of
radiating electro-magnets.
This construction is shewn in Sheet IV. of the accompanying Drawings.
Figure 1 is a longitudinal section of the machine and Figure 2 a front view partly
in section; Figures 3, 4, and 5 shew details as to the winding of the coils, as will be
explained. On the base A is secured a ring frame B, from which project a number
of electro-magnets C radially inwards. The frame also carries a hollow boss B',
from which project a corresponding number (12 shewn in the Drawings) of electro-
magnets C¹ projecting radially outwards. Both sets of magnets have their cores
terminating in iron plates F and F¹, respectively concave and convex, so as to
present between them a narrow annular space. In this space revolves the cylin-
drical shell D containing the coils S, the shell being fixed to a disc J carried by the
shaft E. The coils S are wound on wooden or non-magnetic cores D of elongated
form, as shewn in Figure 3, being connected, as shewn in the Figure, with their
convolutions alternately in opposite directions.
Instead of making each pair of magnets C and C¹, facing each other, present the
same polarity, they may be made to present opposite polarity, the coils S being in
that case duplicated, as shewn in Figures 4 and 5, one set of coils facing the inner
magnets and the other set facing the outer magnets, and those of the one set
extending half way over those of the other set.
In this machine the collection and commutation of the induced currents are
effected by contact rings, commutators, and tangent bushes, as already described.
The machines described with reference to the Figures in Sheets II., III., and IV.
of the accompanying Drawings may obviously be arranged in an inverted manner,
that is to say, the electro-magnets might be made to revolve round a stationary
coiled armature.
Also the machines described as well as that shewn in Sheet I., instead of being
driven by mechanical power so as to generate electricity, may be made to give out
mechanical power by exciting their coils by electricity from an external source.
For the production of small electro-motive force to act in circuits of small
resistance, as for example those presented in galvanic decomposition, apparatus is
sometimes employed depending for its action on the known principle that when a
metal cylinder rotates round the cylindrical pole of a magnet there is an electro-
motive force tending to produce in the rotating cylinder a current parallel to the
axis of rotation.
In order to increase such currents and render them practically serviceable, appa-
ratus of this kind is according to the present Invention arranged as shewn in
Sheet V. of the accompanying Drawings. Figure 1 is a front view shewing half
in elevation and half in vertical section, and Figure 2 is a sectional plan. Two cores A
and A' secured to a base plate B, all of soft iron, form a horse-shoe magnet. Each core is
surrounded by a cylindrical copper shell C secured to an axis d, on which is a
pinion e gearing with a wheel, so that when this wheel is caused to revolve the
shells C revolve round the cores A, A¹, without touching them. Outside the shells C,
but not touching them, are cylindrical iron shells f, f, secured to a plate f2, and
with it forming a horse-shoe magnet. The cores A, A¹, are at their lower parts
surrounded by helices g, g', of thick copper, and similar helices h, h³, surround the
upper parts off, f¹. These helices are put in electrical connection with the shells C
in the following manner :-A shallow vessel k containing mercury has revolving in

page_text: it a disc attached to the shell C, which by centrifugal force causes the mercury to
gather towards the periphery, making contact between the disc and the vessel, and
in like manner contact is made in a shallow vessel l at the top, and thus when the
shells C are caused to rotate an electrical current is created, which is led to the
external circuit by the terminals m, m. The helices h, h¹, on the shells ff, may
be dispensed with, the shells in that case being connected throughout their length
by iron, so that they form an armature for the lower magnet A, B, A¹.
The apparatus may be employed electro-dynamically by sending an electric current
through it, and thus causing rotation of the shells C. For the soft iron magnets
with helices, permanent magnets may be employed.
From the construction above described, it will be seen that the shells C, C¹, being
caused to rotate in an extensive and powerful magnetic field, there is considerably
greater production of electricity than when there is only a disc or cylinder rotating
round the pole end of a magnet, as in machines hitherto known, which act on the
like principle. Further, by using a mercury contact, as above described, there is
comparatively little resistance to rotation, and by making the machine excite its
own magnets, they become charged to their maximum power.
In dynamo-electric machines, as usually constructed, the currents developed in the
coils of the moving armatures are conducted through the coils of the electro-magnets,
in presence of which the armatures move, and increasing their magnetic force cause
more powerful currents to be developed in the armature coils, which further increase
the magnetism until a certain limit of magnetic force is attained.
According to the present Invention this system is modified so as to produce a
chain of dynamo-electric action, as will be understood on reference to the Figures
on Sheet VI. of the accompanying Drawings. These Figures are drawn in diagram-
matic form to give examples of how the links or elements of the chain may be
variously connected or combined.
A single element is represented at Figure 1, a and b being the conductors to the
electro-magnets of a machine, producing two polar fields marked respectively N
and S, between which revolves a coiled armature J, whence currents are led by
conductor marked + and - Figure 2 shews a combination of four such elements,
arranged so that the currents from the last of the armatures return to the first of the
electro-magnets, either or both return wires forming external circuits.
In the other Figures 3, 4, 5, 6, and 7 the elements are combined in various ways,
forming in some cases subordinate combinations, the external circuits being indicated
at the points marked x. In this manner each element, such as is shewn in Figure 1;
may be treated as the cell of a battery, and may be connected either in parallel
order to an external circuit, where considerable quantity of electricity is required at
low intensity, or in consecutive series, where greater intensity is required, or partly
in parallel order, and partly in consecutive series, as may be required.
Although in what has preceded, the apparatus has been mostly described as of the
dynamo-electric kind, whereby mechanical power applied to drive it is converted
into electricity, it is to be understood, as stated above, that with suitable modifica-
tions these apparatus are generally applicable also as electro-dynamic machines, their
rotary parts being caused to revolve and give out mechanical power when electricity
s applied to them. And thus one of these machines may be driven by any suitable
motive power so as to generate electricity, and this electricity may be conducted to
similar machine at a distance, causing it to work and to give out a portion of the
power applied in the first instance.
:
Also, the electric currents generated by such dynamo-electric machines, as have
een described, may be applied to produce illumination in electric lamps of known
onstruction, and also in lamps, such as will now be described, which it is to be
understood may likewise be worked by electricity, generated by machines of different
onstruction, or produced from other known sources of electricity.
In applying electricity for illumination, by causing electric currents of constant
r of alternating direction to pass from one carbon point to another, there are con-
iderable practical difficulties in effecting the delicate adjustment of the distance

page_text: between the carbons, and in maintaining that adjustment while the carbons are
consumed.
In order to effect and maintain this adjustment automatically, a lamp is, according
to this Invention, constructed as shewn at Figure 1, Sheet VII. of the accompanying
Drawings. On a stand A of insulating material two sockets C, C, are mounted on
springs, fixed to metal pieces B, B¹. The sockets hold the carbon rods D, D¹,
which are pressed together at their upper ends by the force of the springs f, f. In
the stand A is fixed a wire coil E, within which is freely suspended an iron core M,
connected by a rod m to a socket G, which holds a stick S of insulating or badly-
conducting refractory material. The electric currents from the line wires L, L', pass
through the coil E, and the carbons D, D', and the core M being attracted upwards,
causes the points of the carbons to separate by thrusting the stick S between them.
A voltaic arc is formed between the separated carbon points, its size being deter-
mined by the thickness of the stick S, which is so adjusted that it does not at first
project above the points of the carbons. The stick S is consumed along with the
carbons, which are always kept pressed towards each other by the springs f,f. A
lamp thus constructed is self-kindling and self-regulating. Should it be accidentally
extinguished, the electric currents being thereby interrupted, the core M will descend,
permitting the carbons to come again into contact, and again close the circuit. A
similar action results when the currents are interrupted and restored in any part of
the external circuit, and consequently the lamp can be extinguished and rekindled
at pleasure by merely opening and closing the circuit at any point. A number of
such lamps can be introduced into the same circuit, either in series or in parallel
connection with one source of electricity.
A modification of this lamp is shewn at Figure 2, Sheet VII. In this case, the
sockets C, C, are freely jointed at the metal pieces B, B', so that the carbons D, D',
are brought together merely by the weight of themselves and the sockets. The
stick S is clamped in a socket G, which has a guide rod acted on at e by a lever r
pivotted at a. On the lever is fixed an armature m over an electro-magnet E
having its coil in the circuit of the lamp.
This form of the apparatus has an action similar to that described with reference
to Figure 1, Sheet VII., but it is better suited for currents of constant direction, the
form shewn in Figure 1 being better adapted to alternating currents.
The pushing up of the stick S may be effected in various ways other than those
shewn according to known methods, whereby electric currents can be applied to
produce movements.
The automatic adjustment of the carbons can also be effected by giving to either
or both an oscillating movement of alternate approach to and recession from each
other, in combination with a continuous approach or feeding movement as the
carbons are consumed.
When either constant or alternating currents are employed, the oscillating move-
ment may be produced by clockwork or other suitable motor, but when the lamp
is worked only by alternating currents it is advantageous to produce the oscillation
by electro-magnetic action of the currents themselves, the continuous feeding move-
ment being given by a weight or spring, or by a float.
One form of lamp arranged to act in the manner is shewn at Figure 8 in
Sheet VIII. of the accompanying Drawings. To a base A is fixed an upright bar B
carrying at its upper end a plate C insulated from it. On the plate C are mounted
rollers D, E, and F, between which a carbon rod G can slide down by its weight
till it reaches the lower carbon rod H. The rod H is held in a socket J having a
guide rod K and jointed at a to a lever Z, which is pivotted at a'. The lever Z is
strained upwards by a spring, and carries an armature N over an electro-magnet M,
the coil of which is in the circuit from L, through the carbons, to L', or back.
Alternating currents, producing successive changes of polarity in E, cause the
armature N to be kept in rapid vibration, thereby giving to the lower carbon H
rapid vertical oscillations. The upper carbon G meets the lower carbon at the
extreme of each up stroke of the latter, but, owing to its inertia, cannot follow it

page_text: down in each rapidly recurring stroke, descending, nevertheless, gradually as the
carbons are consumed. The voltaic are appears when the lower carbon descends
from contact with the upper carbon and this movement is repeated so rapidly that
the impression given is that of a continuous or uninterrupted light.
A modified arrangement of this apparatus is shewn at Figure 7, Sheet VIII.
Here the lower carbon H is stationary and the upper carbon G is lightly pressed on
by a spring r, so that it can slide downwards through holes in the oscillating
arms Z, Z, under the influence of the concussions caused by the vibration. The
action of this lamp is similar to that described with reference to Figure 8, the
corresponding parts in both Figures being marked by similar letters.
According to another modified arrangement shewn at Figure 5, Sheet VIII., the
lower carbon H is supported on a float K immersed in mercury or other liquid in a
vessel Q. The upper carbon G is attached to a spring plate p, p, which is fixed to
bars 0, 0, and which carries the armature N of the electro-magnets M, M. As the
carbons consume, the lower one H is caused to rise by the action of the float K.
Figure 6, Sheet VIII., shews an arrangement similar to that shewn at Figure 5,
but instead of the spring plate p, p, there is a helical spring p¹, the tension of which
can be adjusted by a screw V. For the electro-magnets M in Figures 5 and 6 may
be substituted an arrangement such as shewn at Figure 4, Sheet VIII. In this
case a hollow cylindrical core K of iron or magnetised steel is fixed to the
standard B. Through this core passes a guide rod S which carries the socket for
the carbon G, and a cap to which is fixed a wire helix M surrounding the core K.
Alternating currents passing through the helix M. cause it to oscillate up and down,
giving the required oscillation to the upper carbon.
The vibrating movement, instead of being longitudinal, may be in a direction
transverse to the carbons. An arrangement of this kind is shewn at Figure 3,
Sheet VIII. In this case, the one carbon H is fixed vertical in a socket C insulated
from the stand A. The other carbon G rests obliquely against H, being held in a
socket J on a lever S pivotted at a. The lever S carries a float K immersed in
liquid in a vessel Q, which is fixed to an arm Z carrying an armature N, and
supported by a spring. The vibrations of the armature M are transmitted to the
carbon G, which, by the rising of the float K, is caused to approach H as the
carbons are consumed.
According to a modified arrangement, shewn at Figure 2, Sheet VIII., both
carbons G and H are moveable on fulcra, and are drawn together by springs r, rl.
The one carbon H is connected to a float K, and the other carbon G is connected to
the armature N.
•
For the float and armature arrangement, shewn in Figure 3, may be substituted
a coil M and moveable core K (which is preferably of steel magnetised), as shewn
at Figure 1 of Sheet VIII. The core K is caused to oscillate by the alternation of
the current through the coil M, and at the same time it rises gradually as the
carbons are consumed in obedience to the spring r, the change of the position of the
core in the coil having no sensible effect upon its oscillations.
Having thus described the nature of the said Invention and in what manner the
same is to be performed, as communicated to me by my foreign correspondents, I
claim,
First. In a machine constructed according to the Specification, No. 2006 of the
year 1873, connecting the duplicate coils of the revolving armature respectively to
opposite plates of the commutator, and to a metal ring common to all the coils,
and transmitting the currents induced in these coils through numerous tangential
brushes to the coils of the electro-magnets in parallel connection, as herein described
with reference to the Figures on Sheet I. of the accompanying Drawings.
Second. The construction of a dynamo-electric or electro-dynamic machine,
wherein a flat iron ring wound transversely with coils of insulated wire is caused
to revolve between the poles of electro-magnets arranged in circular order, with
their cores parallel to the axis of the machine and terminating in iron plates

page_text: forming extended polar fields facing the coils of the ring, substantially as herein
described with reference to the Figures on Sheet II. of the accompanying Drawings.
Third. The construction of a dynamo-electric or electro-dynamic machine, wherein
for the coiled iron ring referred to in the preceding claim there is substituted a disc
of non-magnetic material carrying coils of insulated wire wound in the plane of the
disc, substantially as herein described with reference to the Figures in Sheet III.
of the accompanying Drawings.
Fourth. The construction of a dynamo-electric or electro-dynamic machine,
wherein for the disc referred to in the preceding claim there is substituted a cylin-
drical shell carrying coils, and revolving between the poles of interior and exterior
radiating electro-magnets, substantially as herein described with reference to the
Figures in Sheet IV. of the accompanying Drawings.
Fifth. The construction of a dynamo-electric or electro-dynamic machine, wherein
cylindrical shells of copper rotate around and within cylindrical limbs of electro-
magnets, contacts for the electrical currents through the rotating shells being
effected by mercury contained in shallow vessels, within which rotate discs attached
to the shells on their axes, substantially as herein described with reference to the
Figures in Sheet V. of the accompanying Drawings.
Sixth. Combining several dynamo-electric machines of the kinds referred to in
the preceding claims so that they act in series, the currents generated in some
elements of the series being applied to excite the electro-magnets of other elements
of the series, substantially as herein described with reference to the Figures in
Sheet VI. of the accompanying Drawings.
Seventh. The construction of an electric lamp, wherein two carbon rods mounted
in altitudes inclined towards each other are pressed together by weight or spring,
and are kept apart by a non-conducting stick inserted between their meeting points,
the position of the said stick being governed by the action of a solenoid or electro-
magnet whose coil is in the circuit of the lamp, substantially as herein described
with reference to the Figures in Sheet VII. of the accompanying Drawings.
Eighth. The construction of an electric lamp, wherein of two carbon rods pre-
senting their points towards each other, the one is fed onwards as the carbons are
consumed and the other is caused to oscillate rapidly to and from the former, or the
one is stationary while the other has both the feeding and the oscillating move-
ments, substantially as herein described with reference to the Figures in Sheet VIII.
of the accompanying Drawings.
In witness whereof, I, the said Carl Heinrich Siemens, have hereunto set
my hand and seal, this Fourth day of February, in the year of our Lord
One thousand eight hundred and seventy-nine.
CARL HEINRICH SIEMENS. (L.S.)