AN IMPROVED DYNAMO-ELECTRIC OR ELECTRO-DYNAMIC MACHINE
Year: 1882

page_text: LETTERS PATENT to Charles William Siemens, of No. 12, Queen Anne's
Gate, Westminster, in the County of Middlesex, for an Invention of
"AN IMPROVED DYNAMO-ELECTRIC OR ELECTRO-DYNAMIC MACHINE." A com-
munication from abroad by Ernst Werner Siemens, of Berlin, in the German
Winnira
PROVISIONAL SPECIFICATION left by the said Charles William Siemens
at the Office of the Commissioners of Patents on the 16th February 1882.
CHARLES WILLIAM SIEMENS of No. 12 Queen Anne's Gate Westminster in the
County of Middlesex. "AN IMPROVED DYNAMO-ELECTRIC OR ELECTRO-DYNAMIC
MACHINE." [A communication from abroad by Ernst Werner Siemens, of Berlin, in
the German Empire.]
This Invention relates to the construction and arrangement of a machine which
can be used as a dynamo-electric machine for converting motive-power into
electricity or as an electro-dynamic machine for converting electricity into motive-
power, a peculiar feature of the machine being that the same coils serve both for
induction of electrical currents and also for induction of magnetism.
A sheet of iron is bent into cylindrical form but not so as to form a complete cylinder,
an arc of the periphery being left void, and this arc is filled up with non-magnetic
material such as brass so as to form with the iron a complete open cylinder or tube.
This tube is mounted between three sets of guide rollers arranged round an axis so
that it is free to revolve round the axis but without being connected to it by
spokes, and motion is communicated from the axis to the tube in the following
manner. On the axis is fixed a toothed wheel which drives pinions fixed on the
axes of the pairs of guide rollers, and other pinions on these axes gear with teeth
formed in the periphery of the tube, so that the tube is thus caused to revolve
uniformly with the inain axis. The tube is enclosed in a stationary casing of non-
magnetic material such as brass both inside and outside the inner periphery of the
casing, being insulated from the outer periphery by rings of non-conducting
material at each end joining them, these rings being held by suitable bolts or screws
TDC11

page_text: to the fixed framing of the machine. Around the casing are wound lengthwise
coils of insulated wire. The number of these separate coils may vary, but a con-
venient number is 18, which in the following description may be taken to be the
number. The wires of the 18 coils presenting in all 36 ends are connected to a
corresponding number of springs fixed insulated from each other on a stationary
ring at one end of the machine. These springs project inwards from the ring
towards the axis, inclined a little in the direction of revolution from the radial
direction and inclined towards each other so that the ends of the 18 springs fixed
at one side of the insulating ring meet the ends of the 18 springs fixed at the other
side in a plane perpendicular to the axis of the machine. The one end of the wire
of a coil being connected to a spring on one side of the ring, the other end of that
wire is connected to a spring on the other side of the ring, not to the spring which
touches the former but to the spring next in order which touches the first spring
of the next coil, so that if all the 18 springs on the one side remained in contact
with the 18 springs on the other side there would be a closed circuit including all
the coils in order. On the axis are fixed two knives projecting from it so that they
pass between the springs and as the axis revolves each knife separates a pair of the
springs successively. The one knife has its one side covered with non-conducting
material such as ivory and is connected to an insulated ring on the axis of the
machine, the other knife has its opposite side covered with non-conducting material
and is connected to another insulated ring on the axis, and on these two rings rub
brushes connected respectively to the conductors of the external circuit. The
knives may have two metallic sides separated by insulating material and each side
may be connected to a separate ring, this arrangement giving convenience for
reversal of the direction of motion by shifting the brushes from one pair of rings
to the other pair or changing the connections of the brushes. The knives are so
situated on the axis relatively to the void segment of the iron cylinder that the
action of the machine when employed as a dynamo-electric machine is as follows:-
The iron having some residuary magnetism as it revolves within the coil induces
in them electric currents and these increase the magnetism of the iron making it
induce stronger currents in the coils up to the limit of the power of the machine.
The currents thus induced having their direct course through the coils interrupted
at successive points by the revolving knives separating two pairs of the springs, are
caused to pass by the knives, rings and brushes through the external circuit. In a
converse manner electricity being supplied to the coils from the external circuit,
the magnetic cylinder is caused to revolve and the machine works as an electro-
dynamic machine. The power of the machine is increased by surrounding the coils
externally with iron which may be wound as wire round them, and also by
introducing an iron cylinder within the coils.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles William Siemens in the Great Seal Patent Office on the
12th August 1882.
CHARLES WILLIAM SIEMENS of No. 12 Queen Anne's Gate Westminster in the
County of Middlesex. "AN IMPROVED DYNAMO-ELECTRIC OR ELECTRO-DYNAMIC
MACHINE." A communication from abroad by Ernst Werner Siemens of Berlin in
the German Empire.
This Invention relates to a construction and arrangement of a machine which
can be used as a dynamo-electric machine for converting motive power into
electricity, or as an electro-dynamic machine for converting electricity into motive
power. A peculiar feature of the machine is that the same coils of insulated wire
serve both for the induction of electrical currents and also for induction of
magnetism.
Fig 1 of the accompanying Drawings is an end view and Fig 2 is a longitudinal
section of a machine according to this Invention, Fig 3 is a transverse section of
the iron cylinder which operates in the machine as a magnet. Two end frames
nn fixed on a base have bearings for a central shaft and also for three shafts f.
Three bolts or screws m surrounded by short pieces of tube secure to the frames n
two rings ii of non-conducting material such as ebonite. To these rings are fixed
an outer cylindrical shell of sheet brass or other non-magnetic metal, and a.
similar inner shell k³, these two shells and the end rings to which they are fixed
forming together a hollow annular casing within which revolves the cylindrical
magnet a This magnet as shewn in Fig 3 consists of a plate of iron bent round
in cylindrical form leaving about one fourth of the circumference open, and this arc
is filled in with a segment a' of brass or other non-magnetic metal fixed to the iron
and completing the hollow cylinder. Instead of bending the iron a in one piece
it may consist of several thicknesses or of several lengths joined end to end. The
hollow cylinder thus formed is of such size as nearly to fit but to revolve freely
within the casing enclosed by the shells kk' and the end rings i. It is maintained
in position within the casing by three rollers d on the shafts f bearing against its
periphery near one end and other three rollers on the same shafts bearing
against its periphery near its other end. To prevent end movement of the
cylinder the rollers d' are V shaped and enter a V groove in the cylinder. The
cylinder is caused to revolve uniformly with the central shaft 7 in the following
manner. On the shaft is fixed a toothed wheel which gears with pinions q on
the shafts f, and pinions e on these shafts gear with teeth formed at one end
of the cylinder a. The edges of the rollers d d¹ and of the pinions e pass
through slits in the outer shell . Around the shells kk are wound length-
wise a number of coils of insulated wire. A convenient number of such
coils, as shown in Fig 1 is 18, being 6 coils in each of the three
divisions of the circumference between the three blank spaces left for the rollers & d'
pinions e and screws m that fix the annular casing on which the coils are wound.
The number of coils might be varied, but for the following explanation I will
assume 18 to be the number as shewn. The wire of each of the coils has two ends
consequently there are 36 wires connected in the following manner. A ring p of
non-conducting material has fixed on each of sloping sides 18 springs o on the one
side and o² on the other. These springs may extend inwards radially but it is
preferred to incline them, as shewn in Fig 1, forwards in the direction of rotation
of the shaft . The springs o on the one side of the ring p and the springs o' on

page_text: the other side of p incline towards each other so that each spring o meets a spring o¹,
and the meetings of all the 18 pairs of springs is in a plane perpendicular to the
axis of the machine. One end of the wire of each coil is connected to one of the
springs o, and the other end of the same wire is connected to one of the springs o¹
not to that which meets the former but to the spring next in order, so that the
outgoing end of each coil becomes connected through the meeting of a pair of
springs o and o¹ with the ingoing end of the coil next in order, and if all the
18 springs o were simultaneously in contact with the 18 springs o¹ there would be
a closed circuit including all the 18 coils following in order. On the shaft / there
are fixed two knives or separators and which as the shaft revolves pass between
the pairs of springs o and o¹ separating each pair successively. The knife r has on
one side a metal face and on the other side a facing of non conducting material
such as ivory, and the spring 7 has a like facing on the side opposite to that of r,
so that while the knife 7 is separating a pair of the springs it makes electrical
contact only with one of those marked o, and while the knife r¹ separates a pair of
springs it makes contact with one of those marked o'. The knife r is connected
to a ring s fixed insulated on the shaft and the knife ¹ is connected to a similar
ring s², and against these rings respectively rub brushes t and t¹ which make
connection to the wires L L of the external circuit. When the machine is
employed dynamo-electrically by causing the shaft to rotate, the action is as
follows: The iron cylinder a having certain residuary magnetism, in revolving
through the coils induces in them electrical currents, and the currents so induced
react on the cylinder increasing its magnetism until the machine reaches the limit
of its power. The circuit of the coils being broken at successive points by the
knives separating the successive springs through the contact of which if
maintained that circuit would be closed, the currents induced in the coils are
directed by the knives the rings 8 s¹ and the brushes t t into the external
circuit L L. Conversely when electricity is transmitted to the machine by the
line wires L L¹ currents are by the action of the knives rr passed successively
through the coils so as to cause the cylinder a to rotate and drive the shaft 7, the
machine then operating as an electro-dynamic machine. The power of the machine
for either use may be increased by an external shell u of iron encircling all the
coils and by an internal shell u¹ of iron inside the coils. These shells or either of
them may consist of convolutions of iron wire. It is sometimes desirable to make
the machine reversible so that the shaft may revolve in either direction. In that
case each of the knives instead of having one side of non-conducting material
may have both sides metal separated by insulating material between them, and
two additional rings such as 8 8² are provided with their brushes, one side of each
knife being connected to a ring corresponding with s and the other side to a ring
corresponding with 8. By connecting one pair of the brushes t t¹ to the external
circuit the machine is set to revolve in the one direction; but by disconnecting
these brushes from the circuit and connecting the other pair to it, the machine is
set for revolution in the opposite direction.
8
Having thus described the nature of this Invention, and in what manner the
same is to be performed as communicated to me by my foreign correspondent,
I claim :-
First. The construction of dynamo-electric or electro-dynamic machine wherein
a magnet formed as a segment of a hollow iron cylinder revolves within a number
of stationary coils which have their wires connected successively to one another
and to an external circuit in such a manner that the electric currents in the coils
induce magnetism in the revolving cylinder, and the magnetism of the cylinder
induces electric currents in the coils, substantially as herein described.
Second. The combination of the shaft and its toothed wheel h with the
shafts of the rollers & d' and pinions e thereon and the cylinder a with its groove
for the rollers d' and its teeth for the pinions e substantially as and for the
described.
purposes

page_text: Third. The combination of the coil wires with the insulated springs o o' the
knives the insulated rings 8 8¹ and their brushes t t' connected to the external
circuit, substantially as and for the purposes set forth.
In witness whereof I the said Charles William Siemens have hereunto set
my hand and seal this (11th.) Eleventh day of August in the year of our
Lord One thousand eight hundred and eighty two.
C. W. SIEMENS. (L.B.)