Year: 1887

page_text: I, WALDEMAR FRITSCHE, of 31 Karlstr. Berlin, N.W. Engineer, do hereby declare
the nature of this invention to be as follows:-
My invention relates to dynamo-electric machines and comprises an improved
armature coiling and a rotary sliding contact. The improved coiling is applicable to
disc shaped as well as to drum shaped armatures, and is mainly characterized by the fact
that the whole of the wires or rods are arranged in two series or groups, symmetrically
inclined in the direction of the motion, and so connected together, that, in starting
from one point, the whole or any part of the wires may be followed, and by so doing,
the starting point can be reached again. If my improved method of coiling he applied
to disc shaped armatures, the wires or rods may be stretched in zigzag or diagonal
lines, and in two different planes, over the disc, so that the ends are all connected on
the same side of the latter. This also enables disc armatures to be constructed
without a core and at the same time permitting strong wire connections to be
obtained.
In drum shaped armatures the connection of the ends of the wires or rods can only
be made on the outer coil of the drum so that the difficulty hitherto encountered in
conducting the wires over the end faces of the drum is totally avoided.
The rotary sliding contact specially suited to such modes of coiling essentially
consists of a disc rolling along the circumference of the commutator; the shaft or
spindle of which disc is connected with another disc which revolves within a
vessel filled with a conducting liquid, through the medium of which the current is
deflected.
The coiling as applied to a disc armature, consists of two groups of wires or rods,
each of which is situated in a different plane, while they are connected, at the inner
and outer circumferences in circles. These points of connection I hereinafter term
"knots." The number of such knots is equal in both circles and depends on the
number of poles. In a machine having n poles, and supposing it is desired to provide
m knots for each pole, the total number of knots will preferably be NM 1,
or N M2, or N M - 3, and so forth, according as the parallel wires are arranged
in twos or threes. Should this rule not be complied with, the armature obtained
=

page_text: "
would be defective, inasmuch as the length of the sections of its coiling would not be
uniform, and thus a loss of current would ensue, and sparks result.
In one form or modification of my invention the outer and the inner circumferences
of the disc armature, are according to the above formula [(8 × 10) - 1] divided into
seventy nine equal parts, the divisions between which form the knots. These are
numbered in such an order that four sections are formed of which three contain 20,
and the remaining one 19 knots. And, while it is true that the knots of the external
and those of the inner circle are situated on the same radius, yet in consequence of
the oblique position of the wires, the figures placed at the ends of each wire show that
the corresponding knots are 10 intervals ahead of each other.
Taking any knot which I will call No. 1 as the starting point of the outer circle if
we follow the wire leading to the right, we shall first reach in the inner circle the
knot No. 1 which is situated 10 intervals further to the right; by following in the
same manner, the wire proceeding from this knot we shall reach the knot 1 in the outer
circle again, which knot is situated at 20 intervals from the starting point; and so
forth. In continuing thus to follow the wires, from a knot No. 1 of one circle to a
knot No. 1 of the other circle, we shall, therefore, find, that the same wire will always
take us to knots numbered alike, but which in the same circle, are in each case
20 intervals apart. However, after having traced the wire through three knots No. 1 in
the outer circle and there being only 19 intervals between the last two knots No. 1
the said wire will lead to the knot No. 2 next following the starting point. From the
said point the coiling continues in the same way connecting the several knots No. 2
and from knots 2 to knots 3 and so through each successive knot of the armature until
at last it comes back again to the starting point.
The pole pieces are preferably constructed in a shape resembling more or less that
of a trapezoid, formed by the two wires which start from each pair of knots situated
on the same radius. The opposite and the adjacent pole pieces are of opposite polarity.
The direction of the currents generated by the inducing action is from the inner
circumference of the armature to the outer circumference thereof and then back again
to the inner circumference and so on, so that the phenomena due to induction, and their
effects, may easily be controlled upon the armature. The decrease of the currents
takes place in planes which may be assumed to pass through the middle of two
succeeding poles. If it is desired to arrange the parallel wires in twos or threes the
number of knots would be for example 78, or 77; and at the same time, two three or
more wires would have to be conducted diagonally from the external to the internal
circle. In applying my improved coiling to a disc armature I fix on the main shaft
a spoked wheel consisting of two parts the rim of which is made wider towards
the centre. In this rim or crown a ring is clamped, and is insulated from the rim
by a layer of suitable insulating material. The said ring consists of as many insulated
elements as there are knots. Between this ring and another similar external ring
constructed like the said ring are inserted rods which are here substituted for the
wire coiling. These rods are arranged in two rows or layers, or in other words in
two different planes, in such a manner, that, the ends of each pair of rods situated
in two different planes, but belonging to the same knot are in electric communication,
while they are insulated from the rods of the adjacent knots, by insulating layers.
The rods themselves suffice to place the armature rings in electrical communication,
and a core is thus dispensed with; the result being that the distance between the pole
pieces may be reduced to a minimum thereby effecting a corresponding reduction in
the size of the machines. The inner ring e may be secured by means of an insulated
circle, and may serve directly as a communicator or switch, in which case rotary
sliding contacts are arranged for the purpose. These contacts consist each of two
dises, the first of which engages with the circumference of the armature disc, and
receives the armature currents; while the second disc serves to deflect the induction
currents the said disc being mounted on the same shaft as the first disc revolves
simultaneously therewith. The second disc is surrounded by an insulated case or vessel
made of some conducting material and partly filled with a conducting liquid. During the
rotation of the shaft the liquid is, by the action of the second disc thrown against the

page_text: circumference of the said case or vessel, thereby forming a permanent contact between
the whole of the circumference of the said dise and the inner periphery of the vessel.
The armature currents taken up by the first disc therefore, flow through the
shaft to the second disc, and may, by means of a conducting wire connected with the
vessel reach the external circuit. The terminals of the machine are fitted directly on
the two vessels. The sliding contact herein described can also be applied to dynamo-
machines in which the coiling is different from that above specified; and it applies
alike to machines provided with disc shaped armatures and to those in which the
armatures are in the shape of rollers or drums. Instead of the knots of the outer
ring, the knots of the inner ring may be developed into a commutator, or they may
be connected by an independent commutator, mounted upon the main shaft. In
each case, moreover, other contact arrangements, than those described, may be used in
order to deflect the currents.
Instead of a continuous wire, single wires or rods may, if desired, be arranged
between the several pairs of knots. Or, on the other hand, a number of wires at a
time may be used for coiling. As the coiling on such a disc armature, is perfectly
free, and there being nothing to prevent the air from circulating between the coils,
the coiling is much more effective than it has ever been in the dynamos hitherto
known.
Upon drum shaped armatures the wire coiling may be carried out in the same
manner as on disc-armatures as an example supposing the drum-armature is to have
4 poles and 16 knots to be provided for each pole and that the length of the coiling
when removed from the drum casing is four times the width of the drum itself. The
pole pieces therefore, present a square shape. Any other proportion between the
diameter and the length of the armature may be assumed, however; in which case
the pole pieces would acquire the shape of rhombs. There being, in this instance
4 poles with 16 knots each, the whole drum casing is divided into 4x 16-64-1-63
equal parts. The wire, starting on one side from knot No. 1 and extending to the
right reaches the next knot No. 1 on the opposite side; then goes back, always to the
right, to another knot No. 1 on the side from whence it started; then again returns to
a knot No. 1 on the opposite side; and now, as the second section of the drum contains
only 31 knots instead of 32, comes to the knot No. 2, next following its original starting
point. Thus the rest of the coiling continues, the same as in the disc armature before
described, until it attains the starting point again. And in the same way all that has
been said besides, with regard to the disc armature, will likewise apply to the drum or
roller. The adjacent pole-pieces are here, too, of opposite polarity; and the decrease
of the current takes place at the edge of the coiling that is to say in the intermediate
plane between two succeeding pole-pieces.
The direction of the currents generated by induction runs from one side to the
opposite side thereof and back again to the side from which it started and so on along
the divers coils.
In applying the coiling as above described to a drum armature the body of the
drum or roller is mounted upon the main shaft which carries the core. On either side
of the latter rings are fitted, which consist of as many metallic elements, insulated
from each other, as there are knots. The knots are connected with the wires, wire
bundles or rods, which are arranged as before described, in two layers. The decrease
of the current is effected, from the right hand ring, by a sliding contact of any
desirable construction.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to Dynamo-electric Machines.
I, WALDEMAR FRITSCHE of 31 Karlstrasse, Berlin N.W. Engineer, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement
My invention relates to dynamo-electric machines and comprises an improved
armature coiling and a rotary sliding contact. The improved coiling is applicable to
disc-shaped as well as to drum shaped armatures, and is mainly characterized by the
fact that the whole of the wires or rods are arranged inclined in the direction of the
motion, and so connected together that in starting from one point, the whole or any
part of the wires may be followed, and, by so doing, the starting point can be reached
again. If my improved method of coiling be applied to disc-shaped armatures, the
wires or rods may be stretched in zig-zag lines between two circles of different
diameters and in two different planes over the disc so that the ends are all connected
on the same side of the latter. This also enables disc-shaped armatures to be
constructed without a core and at the same time permitting strong wire connections to
be obtained.
In drum-shaped armatures the connection of the ends of the wires or rods between
two circles which are at a distance from each other equal to the length of the drum
can be made on the outer envelope of the drum exclusively so that the difficulty
hitherto encountered in conducting the wires over the end faces of the drum is totally
avoided.
The rotary sliding contact specially suited to such modes of coiling consists
essentially of a disc rolling along the circumference of the commutator; the shaft or
spindle of which disc is connected with another disc which revolves within a vessel
filled with a conducting liquid, through the medium of which the current is conducted
away.
In the accompanying drawings-
Figure 1 is a diagrammatic view of the improved coiling, as applied to a disc-shaped
armature having eight poles.
Figure 2 is a front view of an eight pole armature disc; and
Figure 3 is a section through the whole of the machine fitted with such an armature
and a rotary sliding contact.
and
Figures 4 and 5 are sections of similar machines provided with a drum armature ;
Figure 6 is an elevation of such a drum armature coiled according to my improved
method.
Figure 7 is a diagrammatic view of the improved coiling as applied to a drum
shaped armature having four poles in its developments.
The coiling, as applied to a disc armature, consists of two groups of wires or rods,
each of which is situated in a different plane, while they are connected with each

page_text: other at the inner and outer circumferences, in circles and O. These points of
connection I will hereinafter term "knots." The number of such knots is equal in
both circles and depends on the number of poles. In a machine having n poles, and
supposing it is desired to provide m knots for each pole, the total number of knots
will preferably be a = nm ± 1 or n m ± 2, or n m ± 3, and so forth according as a
single wire is arranged or as the parallel wires are arranged in twos threes and so on.
Should this rule not be complied with, the armature obtained would be defective,
inasmuch as the length of the sections of its coiling would not be uniform and thus a
loss of current would ensue and sparks result.
In the form of apparatus represented in Figure 1 the outer and the inner circum-
ferences and O¹ of the disc armature, are, according to the above formula divided
into 8 × 10 1 = 79 equal parts the divisions between which form the knots. These
are numbered in such order that four sections are formed of which three contain 20,
and the remaining one, 19 knots. And while it is true that the knots of the external
and those of the inner circle are situated always two together in the same radius, yet
in consequence of the oblique position of the wires, the figures placed at the ends
of each wire show that the corresponding knots are 10 intervals ahead of each
other.
Taking knot shown at a Figure 1 as the starting point of the outer circle O, if we
follow the wire leading to the right, we shall first reach in the inner circle O¹ the
knot No. 1 which is situated 10 intervals further to the right; by following in the
same manner the wire proceeding from this knot we shall reach the knot No. 1 in
the outer circle O again, which knot is situated at 20 intervals from the starting
point a; and so forth. In continuing thus to follow the wires, from a knot No. 1 of
one circle to a knot No. 1 of the other circle, we shall, therefore, find that the same
wire will always take us to knots numbered alike, but which in the same circle
are in each case 20 intervals apart. However, after having traced the wire through
three knots No. 1 in the outer circle, (and there being only 19 intervals between the
last two knots No. 1) the said wire will lead to the knot No. 2, next following the
starting point a that the wire will lead instead. From the said point No. 2
the coiling continues in the same way connecting the several knots No. 2 and from
knots 2 to knots 3 and so on through each successive knot of the armature until at
last it comes back again to the starting point.
The pole-pieces are preferably constructed so as to resemble more or less that of a
trapezoid, formed by the two wires which start from each pair of knots situated on
the same radius, as shown in the shaded portions in Figure 1. The opposite and the
adjacent pole-pieces are of opposite polarity, as indicated in Figure 1. The direction
of the currents generated by the inducing action in the whole wire conductor is
marked by means of arrow points on the different wires that is to say from. the inner
circumference of the armature to the outer circumference thereof and then back
again to the inner circumference and so on so that the phenomena due to induction,
and their effects, may easily be controlled upon the armature. The currents are
taken off in planes which may be assumed to pass through the middle of two
succeeding poles as shown by arrows for instance at a and b Figure 1. Supposing
there is a north pole in a, above the plane of the paper, the arrow a indicates the
direction of the rotation of the armature. If it were desired to arrange the parallel
wires in twos and threes and so on the number of knots would be for example 78, 77
and so on; and, at the same time, two three or more wires would have to be
conducted in zig zag lines from the external to the internal circle. In applying my
improved coiling to a disc armature as represented for example in Figures 2 and 3
I fix upon the main shaft w a spoked wheel t consisting of two parts c and c¹ the rim
of this wheel is made widened towards the centre. In this rim or crown, a ring e is
clamped, and is insulated from the rim by a layer of suitable insulating material i.
The said ring consists of as many insulated elements as there are knots. Between this
ring and another similar external ring d, constructed like the said ring e, are inserted
rods d' d² which are here substituted for the wire coiling. These rods are arranged in
two rows or layers, or in other words in two different planes in such a manner, that, the

page_text: ends of each pair of rods situated in two different planes, but belonging to the same
knot are in electric communication, while they are insulated from the rods of the
adjacent knots by insulating layers. The armature rings e and d are only
connected by the rods d¹ and d², and a core is thus dispensed with; the result being
that the distance between the pole pieces may be reduced to a minimuni thereby
effecting a corresponding reduction in the size of the machines. The outer ring e
may be secured by means of an insulated band and may serve directly as a commutator
or switch, in which case rotary sliding contacts are arranged in a and Figure 2.
These contacts consist each of two discs 1 and 2, the former of which as shewn in
Figure 3 engages with the circumference of the armature disc and receives the
armature currents; while the latter serves to conduct away the induction currents.
The said disc being mounted on the same shaft was disk s¹ revolves simultaneously
therewith. The disc s² is surrounded by an insulated case or vessel k made of some
conducting material and partly filled with a conducting liquid. During the rotation
of the shaft w the liquid is, by the action of disc s thrown against the circumference
of the said case or vessel, thereby forming a permanent contact between the whole of
the circumference of the said disc 2 and the inner periphery of vessel h.
armature currents taken up by the disc s¹ therefore, flow through the shaft w₁ to the
disc s, and may, by means of a conducting wire connected with the vessel k reach
the external circuit. The terminals of the machine are fitted directly on the two
vessels k. The sliding contact herein described can also be applied to dynamo-
machines in which the coiling is different from that above specified; and it applies
alike to machines provided with disc shaped armatures and to those in which the
armatures are in the shape of rollers or drums. Instead of the knots of the outer
ring d the knots of the inner ring c may be developed into a commutator, or they
may be connected with an independent commutator, mounted upon the main shaft 0.
In each case, moreover, other contact arrangements, than those described, may be
used in order to conduct away the currents.
The
Instead of a continuous wire, single wires or rods may, if desired, be arranged
between the several pairs of knots. Or, on the other hand, a number of wires at a
time may be used for coiling. As the coiling on such a disc armature is perfectly
free, and there being nothing to prevent the air from circulating between the coils,
the coiling is much more effective than it has ever been in the dynamos hitherto
known.
1
Upon drum shaped armatures the wire coiling may be carried out in the same
manner as on disc armatures; as illustrated in Figure 7 which is a diagram of the
coiling removed from the casing of a drum or roller. In the example shewn,
the drum armature is assumed to have four poles and sixteen knots are provided for
each pole. It has further been assumed that the development of the coiling when
removed from the druni casing is four times the width of the drum itself. The pole
pieces, therefore, present a square shape such as indicated in the drawing by the
shaded portions. Any other proportion between the diameter and the length of
the armature may however be assumed, in which case the pole pieces would acquire
the shape of rhombs. There being, in this instance, four poles with sixteen knots
each, the whole drum casing is divided into 4 × 16 164 163 equal parts.
The wire, starting on one side from knot No. 1 (a), and extending to the right reaches
the next knot No. 1 on the opposite side, then goes back, always to the right, to
another knot No. 1 on the side from whence it started, then again returns to a
knot No. 1 on the opposite side; and now, as the second section of the drum contains
only 31 knots instead of 32; comes to the knot No. 2, next following its original
starting point. Thus the rest of the coiling continues, the same as in the disk
armature before described, until it attains the starting point again. And in the same
way all that has been said besides, with regard to the disk armature, will likewise
apply to the drum or roller. The adjacent pole pieces are here, too of opposite
polarity and the current is taken off at the edge of the coiling that is to say in the
intermediate plane between two succeeding pole pieces as indicated at a and b for
:instance.

page_text: The direction of the currents generated by induction in the whole wire conductor
as indicated by arrow points from one side to the opposite side thereof and back again
to the side from which it started and so on along the divers coils.
Supposing the pole pieces to be above the plane of the paper arrow a shows the
direction of the rotation of the armature.
In Figure 6 the drum armature is shown as it is carried out in practice while
figures 4 and 5 illustrate its application to a machine. The body of the drum or
roller is mounted upon the main shaft w which carries the core t. On either side of
the latter, rings are fitted, which consist of as many metallic elements insulated
from each other as there are knots. The knots are connected with the wires, wire
bundles or rods which are arranged as before described, in two layers d d¹.
current is taken off from the ring by a sliding contact of any desirable construction.
The arrangement of the pole pieces is clearly illustrated by the drawing and requires
no further explanation.
The
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is
>>
First. The above described method of coiling disk shaped armatures the characteristic
feature of which is that the wires or rods are stretched, in zigzag lines, between the
"knots of an outer and an inner circle in such a manner that a number of knots are
each time skipped, and that the ends of the wires or rods again meet at their starting
point, after having touched all of the knots, substantially as described and shown in
the drawing.
Second. The above described method of coiling drum shaped armatures the essential
feature of which is that the wires or rods are arranged upon the surface of the drum
casing in zigzag lines, so that they extend from the knots of one end of the said
casing to the knots of the other end; a number of knots being each time skipped at
either end, and the ends of such wires or rods meeting again at their initial starting
point upon having touched each knot of the armature, substantially as described
and shown.
Third. In dynamo machines provided with a coiling substantially as above described,
the application of pole pieces whose shape in transverse section is determined by two
pairs of wires running from knots, situated, in disk shaped armatures on the same
radius, and in drum armature on one generating line of the envelope plane as above
set forth and shown in the drawings.
Fourth. The arrangement of rotary contacts o consisting of two disks s¹ and s², one
of which is intended for the reception of the armature currents, while the other s³
forms a permanent contact during the rotation with the assistance of the conducting
liquid contained in a vessel k in which it is inclosed; while the said vessel & itself
serves for conducting away the current substantially as above described and illustrated
in the drawings.
1
3711
T
1000