IMPROVEMENTS IN AND RELATING TO DYNAMO OR MAGNETO ELECTRIC MACHINES AND APPARATUS TO BE EMPLOYED IN CONNECTION THEREWITH Communicated him from
Year: 1883

page_text: LETTERS PATENT to Henry Harris Lake of the firm of Haseltine Lake
"
and Co, Patent Agents Southampton Buildings London for an Invention of
"IMPROVEMENTS IN AND RELATING TO DYNAMO OR MAGNETO ELECTRIC
MACHINES AND APPARATUS TO BE EMPLOYED IN CONNECTION THEREWITH
Communicated to him from abroad by’Carl Ludwig Rudolph Ernest Menges
of the Hague Holland
PROVISIONAL SPECIFICATION left by the said Henry Harris Lake at the
Office of the Commissioners of Patents on the 11th January 1883.
HENRY HARRIS LAKE, of the firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, "IMPROVEMENTS IN, AND RELATING TO, DYNAMO
OR MAGNETO ELECTRIC MACHINES AND APPARATUS TO BE EMPLOYED IN CONNECTION
"
THEREWITH [A communication to him from abroad by Carl Ludwig Rudolph
Ernest Menges of the Hague Holland]
This Invention relates to dynamo or magneto electric machines.
It is well known that a dynamo-electric machine consists essentially of an
electro-magnet or magnets and one or more armatures; the improvements
comprised in the said invention and hereinafter described relate to both of these
parts. The improved magnet and armature may be employed either together or
separately in combination with other suitable magnets or armatures. The said
invention also comprises the use of permanent magnets instead of electro-magnets.
The improved machines are applicable for all purposes for which such machines are
usually employed and consequently for the production of motive power by means
of an electric current.
In order to simplify the description of the armature the following definitions
and denominations will be advantageous that is to say, the term Coil will be used
for a coil wound always in the same manner. The terin Solenoid will be used for
a combination of coils, which as regards induction and current, are arranged as a
whole, that is to say, a rise and fall in the induction therein only takes place by a
movement froin one magnetic pole past one of opposite name to one of the samo

page_text: name. The different coils, which together form a solenoid, are not similar as
regards induction or current.
These definitions refer only to the wire connections in the machine, for instance,
coils which belong to different solenoids can, in the construction, form a whole,
while the coils of one solenoid can be separated from one another.
In a dynamo-electric machine, it is necessary that the current, which is
alternating, should always flow in the same direction in the coil of the electro-
magnet. This, as is well known, is effected by bringing the electro-magnet coil
into connection with the induction-wire during one period, and then suddenly,
when the direction of the current changes, breaking the connection and
re-establishing it in the opposite position.
According to the present invention this commutation does not take place
suddenly with the solenoid, but gradually from coil to coil.
In constructing an armature according to the said invention I provide a solenoid
with six coils arranged to be rotated upon an axis between two magnetic poles.
The coils are each connected to two segments of a commutator, the segments of
which are insulated from one another and upon which segments two contact
springs or collectors are arranged to bear. If the armature is rotated the coils
gradually move out of the circuit, and by turning through an angle of 90° the
whole solenoid is thrown out. By continued rotation the coils are again inserted
in the reverse direction. The action of the magnetic poles will produce a current
in the same direction in the circuit between the said springs or collectors. The
resistance of the induction-armature is changeable from zero.
According to a modification of the commutator, one segment is made semi-
circular, the remainder of the segments being of equal proportions. In another
modification of the machine two solenoids are arranged as two electric elements
for quantity. After turning through an angle of 90° the position is such, that the
action of the currents of the different coils will neutralize one another, and after
turning through an angle of 180° the solenoid is in the opposite position: Hence,
in this case also, there will be a direct current obtained. The resistance of the
armature remains constant. It is not necessary that the two solenoids should be
wound separately, they can both if desired, be wound together on the same core, if
the connection with the commutator is suitably arranged.
The different parts of the commutator aro of the same size, or if it is deemed
advantageous, in order to utilize more effectually the various stages of the induction
the, commutator is constructed with unequal segments. The commutator can
moreover be so arranged that during one part of the movement the solenoid is out
of action. By this means several solenoids can be used.
According to the above described modifications I obtain direct currents but not
a continuous current. A continuous, or approximately continuous, current can be
obtained by combining the two systems at right angles to one another, each with
its own contact springs or collectors, which, in this case, have to be arranged for
tension.. Instead of two systems I may employ n systems cach forming an
angle with the adjacent systems. The different solenoids can be fixed on one
rotating axis and only one magnet be employed. The internal resistance of this
combined machine will also be constant in the case of the first modification above
described.
By a peculiar combination of several solenoids as follows, a constant current can
also be obtained, that is to say, four solenoids are electrically connected at a
central point, and there is a double commutator with four springs. In this case,
when the armature is revolving the connection of two adjacent springs or
collectors is formed to produce a constant current. The same number of coils
always remains in circuit and these coils are connected in a similar manner to that
in the case where two systems are arranged at right angles to one another. The
advantage of this arrangement, as compared with those above described, is that
two constant currents can be obtained, which is very advantageous, for example

page_text: for electro-plating, or for experimental purposes, because the electro-magnet can
be supplied by one of the currents so that reversal of the pole is avoided.
If the connection of the solenoids is made so that they can be disconnected at the
centre, then the machine can also be used as the two crossed solenoids above
described. In cases where two commutators are employed, the corresponding
springs or collectors can be set as desired when the commutator is turned
correspondingly without altering the connections.
According to another modification I employ four double solenoids. Both parts
can be wound either separately or together on one core. Only one commutator and
four springs or collectors are required, arranged for quantity. Only two springs
might be employed, but the resistance of the machine would be increased. If one
half of each double solenoid is replaced by one wire connection, another arrange-
ment is obtained which can also be used with two springs. I sometimes combino
more than four solenoids, in which case the connections will be similar to the
examples given above.
In the above described arrangements, one magnet is employed; if there are
several magnets, the poles of which the solenoid passes consecutively, it is easy to
determine the arrangement, the same connections and commutator-segments being
applied in the space between one pole and the next one of the same name, as in
the main system on the whole circumference. The solenoids can be placed
radially, or they can lie parallel to the axis of rotation and rotate between the
magnetic poles, and any number of magnets can be employed as desired. There
must be twice as many contact springs or collectors bearing upon the commutator,
as there are magnetic-poles. But this machine can also be arranged for four
contact-springs if all the similar coils are connected together, and the terminals of
the combined coils are then connected to the adjacent commutator segments in any
suitable manner. The same connections with the commutator segments aro made,
the number of segments being increased according to the number of magnets at the
circumference. It is immaterial where the contact springs are applied provided
each one is properly arranged relatively to the next following magnetic pole. As
regards the construction of the machine, any machine with alternating currents
can be used and changed into a machine with continuous current by one of the
methods above described. Each bobbin, with or without an iron core, is
constructed according to one of the methods above described, as a solenoid with
several coils. The coils can be wound in any suitable manner if the connections
of the coils with regard to the current follow a fixed law. In winding, regard
should also be had to other circumstances, for example that coil in which the
current circulates longest should be subjected to the greatest amount of cooling.
A different section of wire can be used for each coil. It may also be advisable not
to give each coil the same number of turns, in order that the difference of tension
between adjacent commutator segments shall not be too great.
The possibility for providing for all these circumstances constitutes one advantage
of this method of winding wire on an armature, and enables machines to be
constructed which, with a small internal resistance, afford a great amount of power
and useful effect with very little expenditure of metal; they are easy of
construction and the wear and tear is slight.
In winding the wire on the bobbin, the coils may be either one above another, or
by the side of one another, or partly one above another, and partly by the side of
one another, and are suitably connected.
Machines with alternating currents have, as a rule, a number of electro-magnets.
If it is desired to use only one electro magnet, then the form of armature used for
such machines can be employed, for instance the "Siemens" druin armature,
according to the methods above described.
"
If a continuous current is required the armature can consist of two or more
parts crossing one another, for instance, two "Siemens armatures crossing one
another. In order to diminish the extra current this armature is composed of
pieces of sheet metal cut out according to the shape of the armature, or the two

page_text: parts can be separate and cross one another. Each part is made up of longitudinal
pieces of sheet metal or wires and transverse end pieces provided with notches in order
to diminish the extra currents. The wire is wound around the longitudinal pieces.
Two such armatures are now put together in such a manner that the longitudinal
part of one crosses that of the other at right angles thereto. The axis of rotation
passes through both pieces, or a disc or cross of non-magnetic metal is screwed on
at each side, to which discs the journals are fixed. The wire is wound according to
one of the methods above described, either as two or as four solenoids.
Other forms of armatures can also be used.
A cylindrical or square iron rod with an axis of rotation in the centre is sufficient
for one solenoid. But this rod can, if desired, be much thicker in the middle than
at the ends, or a cylinder or dise may be employed, or portions of the core may
project, around which portions the wire is wound. In some cases I employ two
rods, plain or grooved, each wound with half of a solenoid, or I effect the winding
on a ring which may have projecting pieces.
These forms of armature can also be used for obtaining a continuous current by
the combination of several solenoids on separate armatures.
Moreover several solenoids can be wound separately on one armature and these
used separately or combined. For instance two rings may be twisted round 90°
and wound one above the other. For the special arrangement for a continuous
current four radial rods can simply be used around an axis of rotation. Other
forms of core and methods of winding may also be employed.
The armature core should be composed of iron wire or sheet iron in order to
weaken the extra currents as much as possible; and the said core can also be made
hollow. The arrangement on an axis of rotation, and the construction of the
commutator can be as usual. The core can also remain stationary while the wire
alone revolves. The wire is wound on two drums which are screwed together over
the core, and can therefore, at any time, be removed for cleaning or other purposes.
The construction of the wire bobbins has been hereinbefore referred to. For great
intensity of current very thick wires, or rods, would require to be used, but the
current generated therein would partly be dissipated in the mass, which not only
causes waste of motive power but also gives rise to overheating of the machine. I
therefore construct the conductor of rods which are composed of several rods of
smaller section. These smaller rods which have the same length as the compound
rod, are rivetted, screwed, or soldered together. In order to prevent the electricity
from passing from one rod to another at the ends, each single rod, before being put
in place, is lacquered or oxidized on the surface, and if required lacquered after
that, or spun round with some suitable material. As the difference of tension in
the adjacent rods is not great, very little insulation will suffice so that in many
cases the rods can be put together without any preparation, as the usual amount of
dirt on the surface would be sufficient. The different compound rods must be
properly insulated from one another. If for instance an armature is to be constructed
with these rods, the inner part will be made up of rods which are insulated from
one another and held together around the axis of the armature in the same manner
as the different segments of a commutator. In a ring-shaped recess between two
Hanges iron wire is wound to form the iron core. On this core the said rods are
placed in such a manner that one end of one rod is connected with one of the
Hanges by screws or other suitable means, and the other end of an adjacent rod is
connected with the other flange. If it is desired to make the inner part of the
ring efficient for induction, then the central portion of the core is not made thicker
than is required for the current. The whole system is then fixed on the axis.
The projections on the electro-magnet pole can, in this case, project into the hollow
of the ring, or a second electro-magnet can be used for this purpose.
For druin armatures the rods are laid on the surface of the drum parallel with
the axis of rotation. The rods are then connected by plates which are fixed
on the end surfaces of the drum, vertical to the axis of rotation. The plates which
are insulated from one another are connected with the rods and are alternately

page_text: The axis
can also be used as a means for fixing them if the plates are suitably made; but a
ring-shaped part which passes round the axis must be made as small as possible,
otherwise the advantage of the crescent-shape, which impedes the circulation of the
induction-current in the plate itself, is lost. In order to weaken this current slits
are also made in the plates.
placed on both sides of the axis and held together by insulated bolts.
For cooling purposes, in the case of drum-armatures, I make one or both of the
journals hollow and by this means permit air to pass through the core, which air
escapes through suitable openings. The current of air is either produced by
centrifugal force or by a special blast. I can also use the two modes of construction
last described with any of the ordinary methods of winding the wire.
I will now proceed to describe the present improvements in electro-magnets.
If through any cause the electro-magnet of a dynamo-electric machine is
momentarily increased in strength, then a kind of after effect is produced when the
action which caused the increase, ceases, whereby the inachine remains in increased
activity. In order to utilise this reaction I wind a few more coils beyond the
electro-magnet coil, which always remain in the circuit, either over, by the side of,
or together with, the first wire. The armature is connected with one end of the
coil, while the conducting wire which has to transmit the current is brought into
intermittent contact with two points in connection with the additional coils by
means of any of the well known commutator devices. The contact must pass
without interruption from one point to the other. When, by too great difference
of tension, sparks are produced between the said points then a gradual change is
effected similar to the case of the commutator for the armature first herein
described, whereby only one contact-spring is required, connection with one of the
said points not being broken. The spring can either be pushed to-and-fro across
the contact piece, or a rotary motion can be used. If the commutator is stationary,
the revolving spring remains in connection with the conductor through the axis.
If the commutator revolves, the different parts of it are connected with rings,
insulated from one another, on which springs are arranged to bear, which springs
effect the connection with the electro magnet coil. The time during which the
extra coils of wire are introduced or excluded can easily be altered according to
requirements, by means of different sized commutator segments.
In another arrangement for increasing the action of the electro magnet, different
coils are wound by the side of one another on the core of the electro-magnet. These
are all connected on one side with one wire, and on the other side with pieces of
insulated metal on which is arranged to bear a spring connected with the other wire
which transmits the current. By the movement of the commutator (which may
be either to-and-fro or rotary motion, in the latter case the pieces of metal being
arranged in a circle) the current will pass through the coils, one after another,
therefore the action of the current, concentrated on a short distance, will be
continually moved across the core of the electro-magnet.
These arrangements can be applied to any kind of electro-magnet.
In another form of construction I employ a surrounding iron case which takes
up the power which would otherwise be lost outwards from the coils of wire. The
wire coils net inductively directly on the armature rotating between the poles.
By reason of the direct inductive effects of the wires a drum armature can be
used, without an iron core, in this form of construction.
For large dynamo electric machines the construction will be very difficult, when
only one large electro magnet of the usual kind is employed. For this reason
several electro magnets are used which act together. Assuming two electro magnet
cures placed side by side, and the current flowing in opposite directions through
the coils, the currents, at the parts opposite one another, will be neutralized and
their useful effect lost. This remark also applies to other sections of the core.
In order to remedy this defect, and yet retain the divisibility of the machine, the
electro-magnet is constructed as follows, that is to say, the core is composed of
different pieces, and the wire is wound on several separate drums. The dividing

page_text: surfaces of the core and the wire must be at right angles to one another, as the
divisions of the core must be parallel to the magnetic axis.
In order to be able to regulate the current of the dynamo electric machine with
a constant speed of rotation of the armature, one or several parts of the wire on
the electro-magnet, are arranged in such a manner that these can be brought into
and out of circuit according to circumstances. As the power of the electro-magnet is
altered by this means, the same strength of current can be produced under different
extraneous conditions.
The electro-magnet is brought into and out of circuit in a similar manner to
that above indicated but with this difference that the contact-spring, only, is
shifted when regulation is required either by hand, or automatically by the current.
In the latter case an electro-magnet influenced by the current is employed, together
with an armature or similar device when the current is weak, and when only one
change of contact is required. When the current is strong I employ a centrifugal
governor which is driven by an electric motor by means of the current from the
machine itself. The change in the speed of the motor, by reason of the change in
the intensity of the current, effects, by means of the centrifugal governor, the
desired movement of a contact-lever.
In some instances I arrange a coupling to be thrown in and out of gear
indirectly by the current, any motor (for example the same which drives the
machine) can be used to effect the movement of the contact-spring. I sometimes
employ a bell-crank-lever moved by a coil with an iron core, the current which has
to be regulated passing through the coil; and this lever shifts a clutch coupling to-
and-fro upon a spindle, which is, by means of mitre gear wheels, turned either one
way or the other by a shaft driven by the motor. The said spindle is arranged to
move a contact-lever. This spindle remains stationary when the current is of the
proper strength, but begins to move as soon as a small change occurs, till the
previous intensity of current is reproduced by placing more coils on the electro-
magnet in or out of circuit.
If the whole current of the machine has not to be maintained constant, but only
a current in a branch circuit, then the motor or the wire-bobbin must be brought
into circuit with a branch conductor. By this means the current is also regulated
in the other branches.
I can also by the following arrangement, obtain a regulation of the current with
the armature revolving at an even speed, that is to say, I wind two wires on the
electro-magnet. The resistance of these wires and the connection with the
armature and the external circuit are arranged according to circumstances. Tho
core of the electro-magnet can be surrounded by only one continuous bobbin, or by
two separate bobbins. The two wires can be wound together, or each wire by
itself can be wound on one or more bobbins, which can then be placed side by side,
or ono above the other on the core of the electro-magnot. The mode of winding
depends on different additional circumstances, for instance how the required cooling
or the necessary insulation can best be attained. For this appartus the saine.
fundamental principle holds good as for all other induction-apparatus. Thus two
wires in which a great difference of tension could arise, would not be wound on in
such a manner, that they touched one another, but each ono would be wound by
itself on properly insulated bobbins. A number of electro-magnets could moreover
act upon one or more armatures, in which case all of then must be wound in such
a manner that at any strength of current they have between them the same
magnetic power.
If each electro-magnet coil is considered as a whole then only two arrangements
are possible, but a third arrangement can be obtained by dividing one of the
wires.
⚫ The commutator brushes are, in order to prevent sparks, placed in the most
favorable position for the strongest current and are therefore not in the right
position for the weak currents. By thus fixing them for stronger currents, an increase
occurs in the electro-motive force.

page_text: The employment of two electro-magnet coils is also especially useful for electro-
metallurgical purposes as not only is the intensity of the current maintained at the
proper amount for each piece, whatever be the number of pieces in each bath and
whatever be the number of baths used, but the electro-magnet poles are not so
easily shifted as in the ordinary machines, and can under certain circumstances be
entirely prevented from shifting. For this purpose it is only necessary that the
magnetizing effect of one coil should be greater than that of the other coil in the
case of a counter current.
The arrangement is also very convenient for machines used for experiments in
the laboratory. The ordinary dynamo-electric machine is well known to be very
sensitive to changes of resistance and produces beyond a certain amount, hardly
any more power. For this reason the magneto-electric machine has justly been
preferred. With the coiling of the electro-magnet as described, the improved
machine can however be used in a manner very similar to an ordinary galvanic
pile, and has this advantage over a magneto-electric machine, that it produces far
greater power for the same cost and weight.
This arrangement is also convenient in many cases for an electric-motor. In
the case, for instance, of variable speed of rotation, the counter electro-motive force
of the motor and hence the intensity of the current is also variable. In the case
of an ordinary machine the electro-magnet will, when the speed is very great,
receive too little current, or too much when the speed is slow. This can be
prevented by the peculiar coiling of the electro-magnet.
The regulating apparatus above described can be employed in combination with
the above described methods for arranging the two electro-magnet wires. In this
case the said apparatus can be applied to both, or only to one of the electro-magnet
wires. The connection of one coil with the other can also be made, not as a fixture,
but adjustable along the latter coil, whereby the electro-motive force will be.
changed.. The latter coil is then constructed of different pieces and these are
connected by contact pieces, which are insulated from one another. Springs
connected with the first coil can slide to-and-fro in any direction across these contact-
pieces.
Other arrangements hereinbefore described can also be used in combination with
two electro-magnet wires, either for one of the wires or for both.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Harris Lake in the Great Seal Patent Office on the
11th July 1883.
HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, London, "IMPROVEMENTS IN AND RELATING TO DYNAMO
OR MAGNETO ELECTRIC MACHINES AND APPARATUS TO BE EMPLOYED IN CONNECTION
"
THEREWITH A communication to me from abroad by Carl Ludwig Rudolph
Ernest Menges, of the Hague, Holland,
Article 1st It is well known that a dynamo-electric machine consists of an
electro-magnet with an induction armature. The improvements hereinafter
described have reference to both these parts and the inventor reserves to himself
the right of using them both combined, or either of them separately, in combination
with any known appliance, consequently also of using a permanent magnet in lieu
of an electro-magnet. The use of the improved machine for all purposes for which
such machines are employed is reserved, hence also for the purpose of producing
motive power by means of an electric current generated by other means.
THE INDUCTION ARMATURE
Article 2nd In order to simplify this specification certain terms and diagrams will
be used.
16
"
"Spiral" will be the term for a coil of wire always wound in the same direction.
"Solenoid" is to stand for a combination of spirals working as a whole as
concerns induction and circuit, that is to say, there occurs but one rising and
receding in the induction during the movement from one pole of the magnet
around the other, and back again to that of the same polarity. The different
spirals composing a solenoid do not exactly equal each other as regards induction
or current.
This definition refers only to the wire connections in the machine, as for instance
spirals belonging to different solenoids may form a whole in construction, while the
spirals of a solenoid may be separated from each other.
Article 3rd-In a dynamo-electric machine it is necessary that the current, which
naturally has an alternating direction, should always have the same direction in
the electro-magnet of the machine. As is well known this is effected by
temporarily connecting the wires of the electro-magnet with the induction wire
during one phase and then, when the direction of the current is reversed, suddenly
breaking the connection and re-establishing the same in an opposite position
Now the methods of the inventor consist in causing this commutation in the
solenoid not to take place suddenly, but gradually from one spiral to the other.
Article 4th In the diagrams shown in the accompanying drawings and intended
for explaining the methods and their application and the manner of their execution
a spiral is illustrated at 8 below Figure 1 and a solenoid between a, b, Figure 1
while the indicated circuiting or connection of the spirals will allow of drawing
conclusion as to the action. It is only necessary to suppose the small circles to be
so arranged around a core that the points of contact are turned towards the perso
looking at the drawing. Thus the two solenoids a, b, and α, b₁, in Figure 3 wil
act like magnets having their poles of similar name at a, a₁, and b, b₁, when th
electric current is conducted from a to b and α, to b₁. It is furthermore to b
remembered that only when a dot is placed at the intersection of two lines is
conducting connection between the two wires, signified, not otherwise.

page_text: Article 5th a, b, in Figure 1 represents a solenoid with six spirals. The
solenoid must be considered as arranged between the poles N.S of a magnet and
rotating on a central axis at a right angle to the figure. The spirals are each
connected with two of a number of metal pieces insulated from cach other, two
contact springs P and P, intended for receiving the electric current, being caused
to bear on the said metal pieces. In the position shown the whole solenoid is
included in the circuit between P and P. When the entire system is rotated the
spirals gradually leave the closed circuit and after a revolution of 90° the entire
solenoid is switched out of circuit. The rotation being continued, the spirals are
agnin included in the circuit in an opposite direction. It will thus be easily seen
that the effect of the poles of the magnet is such as to produce a current having the
same direction in the circuit between P and P₁. The resistance of the armature is
variable beginning from zero.
A modification of the commutator arrangement is shown in Figure 2, the effect.
being the same as that above described.
Article 6-Another method is shown in Figuro 3. It will be seen that the two
solenoids are here switched as to quantity in the manner of two electric elements.
On being rotated 90° the condition of the circuit is such as to cause the impulses of
the current of the different spirals to exactly counterbalance each other, if this does
not happen to be the position free from induction; ou being rotated 180° the
solenoid is onclosed in the circuit in a diametrically opposite direction. A currerit
having the saine direction is thus obtained in this instance also. The resistance of
the induction armature remains constant.
It is not necessary that both solenoids should be wound separately, as both may
be wound on the same core, it being only essential that the connection with the
commutator be made as in Figure 3.
Article 7th The commutator parts are shown as being of equal size, in order to
obtain a better utilization of the phases of induction, howover, it may be found
advisable to construct the commutator with sections of different sizes as in
Figure 4, such construction being also applicable in the case of a commutator of
the second method referred to under Article 6th. In all the arrangements
hereinafter described this construction may also be employed. The arrangement
may also be such that, during a certain part of the movement, the solenoid remains
entirely out of circuit as in Figure 5, this is applicable in the case of the first
method of commutation referred to under Article 5, and also in the case of the
second one referred to under Article 6. Several solenoids may thus be employed,
the space from c to d and from & to d₁ being occupied by the commutator
segments of the other solenoids.
Article 8-By means of the methods described under articles 5th and 6th,
currents of equal direction are obtained, but no constant currents. When a
constant current is desired this may (at least approximately) be obtained by the
combination of two systems turned at an angle of 90° with regard to each other,
each system having its own contact springs (commutator brushes), which are then
to be switched as to tension. Instead of two systems, the number employed inny
also ben and the angle at which they are turned with regard to each other may
be The different solenoids may in such case be mounted on one and the same
axis of rotation and only one magnet may be employed; but even this must also
be considered a combination of a number of separate machines. It is obvious that
the inner resistance of the combined machine is constant also in the case of the first
method described under article 5th.
Article 9th-A constant current may also be obtained by means of certain
connections of several solenoids. Figures 6. 7 and 8 illustrate some of such
arrangements.
In Figure 6 four solenoids are connected in the middle in a conducting manner.
Furthermore a double commutator having four springs (brushes) is employed. In
following up the result of the induction during the rotation it will be found that

page_text: the combination of two brushes arranged side by side will cause a constant current,
the same number of spirals being always included in the circuit and being con-
nected in the same manner as would be the case with two systems shifted at an
angle of 90° as under article 8th The advantage of this arrangement above that
described under article 8th is, that here two constant currents can be maintained
which will be found very desirable for galvanoplastic purposes or for experimenting
machines, for instance, the electro-magnet is here excited by one current and a
reversing of the poles is thus prevented. In a similar manner each of the different
arrangements hereinafter described has its peculiar advantages which will readily
present themselves on close examination.
If the connection of the solenods be made detachable in the middle, then the
machine may also be used in the manner of two solenoids crossing each other as
described under article 8th. It is further to be mentioned that in the case of two
commutators, the brushes pertaining to each other may be adjusted at will if the
commutator be turned accordingly, without altering the connections.
Article 10th-In Figure 7 the induction armature consists of four double
solenoids. Both parts may be wound on one and the same core either separately
or together (v. article 6).
111
Only one commutator and four brushes P, P, P P to be switched as to quantity,
are here required. Two brushes only at p and p₁ may also be employed, but this
only increases the resistance of the machine.
By substituting for one half of each double solenoid a wire connection, the
arrangement shown in Figure 8 is obtained, which will at once be understood
from the above description. The same may be used with two brushes, likewise.
More than four solenoids may also be connected with each other, the connection
being made in a similar manner to the examples shown.
Article 11th One magnet only is also assumed, but if there be more magnets the
poles of which are continually being passed by one and the same solenoid, the
manner of arrangement is always easily ascertained, the same connections and
commutator segments being here arranged, in the space from one pole to the next
pole of the same name, as in the main diagram along the entire periphery.
An example of this will be found in Figure 9, the manner of connection being
the same as in Figure 8. The solenoids are shown as extending radially, though
they may if desired be parallel to the axis of rotation so as to rotate between the
poles. Purposely only a part of the entire periphery is shown in the drawing so as
to indicate that the number of magnets may be varied to any desired extent. The
number of brushes bearing on the commutator must be double the number of the
maguet poles. The machine, however, may also be adapted for four commutator
brushes by first connecting all similar spirals together and then connecting the pole
wires of the combined spirals into solenoids, as in Figure 8, and with one set of
commutator segments adjoining each other. The same connections are made with
the next set of commutator segments and so on, it being obvious that it is only
necessary to repeat the commutator of Figure 8 as often as there are magnets on
the periphery in Figure 9. It is evident from the above that the points at which
the brushes are applied are entirely optional so long as each of them is arranged
according to Figure 8 as regards the adjacent poles of the magnet.
Article 12th. As regards the construction of the machine, any machine with
alternating currents may be employed for the purpose, and, by means of any of the
methods above described, may be converted into a machine with a current of
unvarying direction. Each coil of wiro with or without an iron core is, according
to any one of the examples described, constructed as a solenoid with several spirals.
As already stated under Article 2nd, the spirals may be wound in any desired manner,
it being necessary only to connect the several spirals according to a certain rule with
relation to the circulating current, that is to say, the manner of winding may be
governed by different circumstances. Thus the spiral in which the current circu-
lates during the greatest length of time, is mostly to be exposed to cooling. Wires
of different sectional size may be employed for the several spirals. It may also be

page_text: found advisable not to give each spiral the same number of convolutions, the
difference in tension of the adjoining segments of the commutator being taken into
consideration, so as to prevent the said difference from becoming too great. The
number of spirals to be employed for the solenoids is also governed hereby.
The advantage of this method of winding the wires of induction armatures lies
in the fact that it is thus rendered convenient to make duc allowance for all these
and other circumstances, whereby machines may be produced combining with a
low internal resistance great power and useful effect, and requiring only a small
quantity of metal, being easily constructed and exposed to but little wear.
In practically winding a coil of wire a pattern is first made each spiral being
supplied with a consecutive number, the two ends of the wire being distinguished
by + and -, , and the consecutive order of arrangement of the spirals in the real
coil of wire is then decided upon, no matter how they are to be arranged, either
above one another or laterally, or both. Now, in winding the wire, the same is
always given the corresponding number and index from the pattern. After the
coil is finished the connections are made according to the numbers as in the
pattern.
With some slight alteration the construction of machines with alternating
currents, may also be adapted for a constant current by modifying the same
according to Figure 9.
Article 13th. Machines with alternating currents generally have a great number
of electro-magnets. If it be desired to employ but one electro-magnet, the shape
of armature generally used in such machines may be made use of, likewise, such as
the cylinder armature of Siemens in the diagrams Figures 1, 2, 3, 4, or 5. As
regards the arrangement shown in Figure 3, both of the solenoids as already stated
may be wound on one core, but they must always remain as two solenoids with
regard to their connection in the circuit (Article 6th).
In case of a constant or continuous current, the armature may consist of two or
more parts arranged crosswise, say two Siemens armatures crossing each other, or
in the manner shown in Figure 10. In order to reduce the number of extra
currents this armature is composed of pieces of sheet metal cut as shown in the
Figure.
Both parts may also be kept separato in the manner of two armatures crossing
each other as shown in Figure 11, Figure 12 being a sectional view thereof on the
line c, d, Figure 11. The part a, b is formed of pieces of sheet metal or of wires,
and the sections a, c and b, d, are provided with slots for the purpose of reducing
the extra currents. The wire is wound around a, b,. Two such armatures are put
together in such a manner that the part a, b of one enters the space between c, d
of the other, as shown in Figure 13. The rotating shaft may either pass through
both pieces, or a disc or cross of non-inagnetic metal may be screwed on to both
sides c, c, d, d, the said disc being provided with pivots. Tho winding of the wire
is effected according to one of the examples already described either in the shape of
two or of four solenoids.
Article 14. Several other shapes of armature may also be employed. In order
to dispense with the necessity for always describing at great length the manner of
winding the arinature, the direction across the wire coil is indicated by a dotted
line. The limits of the line, illustrated in the manner usually employed for
indicating the measures in constructional drawings, show the extent of the winding
of the wire coils. In further illustrating the winding of the coils, the letter S shows
that a whole solenoid is wound over the space indicated, 'S signifies half a
solenoid, that is to say, only half of the number of spirals forming a solenoid, while
S/, indicates that, of all the spirals composing a solenoid, only half of the wire has
been wound.
The dimensions and the cross section of the armature at right angles to the figure
are optional.
Article 15th. As already stated (Article 6th) two solenoids, Figure 3, may also be
wound on one core. But one solenoid, as in Figure 1; may also be wound on two

page_text: cores (each S/) these forming only one solenoid as far as their wire connections are
concerned. It appears clear from this, that each form of armaturo may be wound
according to both methods of commutation. This may be easily indicated in the
Figures by changing the index of S. Only the first method will, therefore, in the
first place, be considered hereinafter, as the alterations required for the second
method will then be easily understood.
Article 16th. A cylindrical or square iron rod having a rotary shaft in the centre
will be sufficient for a solenoid. The rod may also be much thicker in the middle
than at the ends (Figure 14). By shortening or rounding off the same a cylinder
or disc (Figure 15) is obtained. In cases where the winding exceeds the diameter
of the cylinder, pieces of the core may be left protruding on the surface of the
cylinder to be wound with the wire (Figure 16).
Two rods, either straight or angular as in Figure 17, may be wound with S'/,,
which leads to the winding of a ring (Figure 18) which in turn may also be
provided with protruding pieces or lugs, similar to Figure 16.
Article 17th. These shapes of armatures may also be used for steady or continuous
currents obtained by the combination of a number of solenoids on separate armatures,
(article 8th).
Several solenoids may also be separately wound on one armature and then used
separately or according to article 8th. Two rings for instance turned at an angle of
90° as in Figure 18 and wound one over the other represent the manner of
arrangement shown in Figure 19. Thus also in the Figures 15 and 16 another
solenoid may be wound across.
Article 18th. For the special arrangement for continuous currents, articles 9th
and 10th, four radial rods mounted on one rotary shaft may simply be employed.
These rods, however, may have the shape shown in Figure 20, from which
Figures 21 and 22 originate similarly to Figure 16.
Different solenoids may be arranged above the same part of a core, thus the next
step is from Figure 20 to Figure 23 and thence to Figure 24 resulting in a manner
of winding the cylinder entirely different from Figure 21.
In the above the core rods are always shown as being placed radially but they
may also form a quadrangle as in Figure 25, thus leading to the ring Figure 26.
The rods placed opposite to each other in Figure 25 may be transformed into a
ring, similarly to Figure 18. Thus in place of the four rods two rings turned nt
an angle of 90° are obtained which on being wound together result in the ring
Figure 27 showing an entirely different manner of winding from Figure 26.
It has already been mentioned (Article 10th) that more than four solenoids
may also be employed. Therefrom result, for instance, Figures 28, 29 and 30 for
six solenoids.
Article 19th Separate solenoids may be wound on one core and vice versa
solenoids connected to each other may be wound on separate cores, each solenoid
having its own electro-magnet. Supposing for instance four solenoids to be wound
in pairs on two rods, then it follows that when one of the latter stands directly
opposite to the pole of the magnet, then the other one must be distant from
the pole of its magnet.
More than four solenoids may also be used. In the case of six solenoids, on
three rods, the first rod being opposite to the poles, the second one will be
turned and the third /, away from their poles. It is not, however,
necessary that the movement from one pole to the other should take place exactly
at the end of one half rotation, and the rods may, for instance, be arranged
similarly as in Figure 9 on the periphery of a wheel. In that case the second rod
will not be opposite the second pole when the first one is directly opposite to the
first pole, but it will be '/, of the distance between the poles further on, and the
third will be further on, just like /, and /, as previously stated, because
there the distance between the two poles was T. Any desired number of rods
may thus be arranged on the periphery, the fourth rod being then /, more
advanced, that is to say, directly opposite to the next pole, and so forth.

page_text: Article 20th, As regards the construction of the armature cores, it may be stated
that they should be composed of iron wire or sheet metal in order to weaken the
extra currents as much as possible. The core may then be made hollow. The
arrangement on one rotary shaft and the manner of arranging the commutator
may be as usual.
The core may also remain stationary while the wire only rotates, this being
very easily done in the manner of winding as employed in Figure 15. The wire
is wound on two tubes or bobbins, which are screwed together above the core so as
to be easily removable at any time for cleaning or other purposes.
Article 21. The construction of the wire coils has already been referred to
(Article 12). For great intensity of current very heavy wires or rods would be
required. The currents generated in the same, however, are partially equalized in
the mass itself, thus not only producing waste of power, but also increasing the
liability of the machine to become overheated. The inventor therefore constructs
the conductor of rods, the said rods being composed of a number of rods of smaller
transverse section. These rods which must be of the same length as the compound
rod are, at their ends, rivetted or screwed together, or soldered with or without
any screws or rivets. In order to prevent the passage of electricity from one rod
to the other, except at their ends, the several rods, before being put together, are
first varnished, slightly oxidized, and, if necessary, again varnished and spun over.
As the difference of tension of rods adjoining each other is not large, there is but
very little insulation required so that the rods may, in a good many instances, be put
together without having been prepared in any manner, the usual impurity of the
surface alone being sufficient. The different combined rods must be properly
insulated from each other, the same as in the case of common conducting wires.
Assuming an armature, according to Figure 18, to be constructed with these
rods, then the inner part is constructed of rods (which may in turn be each'
composed of a number of rods) as shown in Figure 31 a, b, c, the said rods being
insulated from each other and held together around the axis of the induction
armature in a similar manner to the parts of a commutator-Iron wire is wound
in the annular space between a and c thus forming the iron core. The said rods
are arranged above this core in such a manner that one end is fastened to a by
screwing, soldering, or other suitable means, while the other end is fastened to tho
part c, that is to say, not of the same, but of the next or still further removed rod,
and so on.
The
When it is desired to utilize also the inner part of the ring for induction, then
the part b is made no thicker than may be deemed proper for the current.
fastening of the whole system on the shaft is then effected according to Figure 33.
Lugs on the electro-magnet poles may extend into the hollow space of the ring, or
a second electro-magnet may be employed for the purpose.
Article 22nd. For cylindrical armatures the rods are arranged on the surface of
the cylinder parallel to the axis of ro'ation. The connection between the rods is
here established by means of plates, Figure 33 attached to the end surfaces of the
cylinder perpendicularly to the rotary axis A. The said plates which are insulated
from each other, are connected with the rods at a and b. The plates are arranged
alternately on both sides of the axis and are held together by means of insulated
bolts. The axis may also be used as a means for effecting the fastening, if the
plates be formed according to Figure 34; the annular part surrounding the axis,
however, must be as small as possible, as otherwise the advantage derived from the
crescent shape would be lost, the said shape rendering the circulation of induction
currents within the plate itself more difficult. For weakening the said currents
incisions or slots are also formed as indicated in the Figures.
For cooling the circuit in cylindrical armatures, the inventor makes one or both
of the pivots of the axis of rotation hollow and thus conveys air into the core,
which air escapes through apertures between the circuits. The current of air is
supplied either by the centrifugal force of the armature itself or by a separate air-

page_text: blast apparatus.
The inventor reserves to himself the right of applying the
constructions described under articles 21 and 22 to any known manner of winding.
THE ELECTRO-MAGNET.
Article 23. Excepting articles 25 and 26, all the arrangements described in
these and the following paragraphs are to be employed in every form and arrange-
ment of the electro-magnet cores. If several electro-magnet cores be employed
in one machine then the arrangements described must be fitted to each of them.
The wire parts that coincide or correspond with one another are then connected
according to circumstances for tension or quantity.
On momentarily increasing the strength of an electro-magnet of a dynamo-
electric machine by any means whatever, a sort of after effect takes place, when
the cause of the increase in strength ceases to act, whereby the increased action of
the machine is maintained. In order to utilize this circumstanco a few additional
coils a, b are wound above, or to the side of, the wire la of the electro-magnet or
together with the said wire, the latter being shown in the diagram Figure 35 and
remaining always included in the circuit. The induction armature is in connection
with L while the conducting wire L, intended for conducting the current off is
alternately connected with a and b by means of any of the numerous known forms
of commutator. It is necessary only to have the contact made from a to b without
interruption. If sparks should be formed in consequence of too great a difference
in tension between a and b, a gradual change must be made after the manner of
the commutator in the induction armature Figure 1 article 5th, one commutator
brush only being required, as the connection with a will not be interrupted. The
commutator brush may either be moved reciprocally over the contact pieces or a
rotary motion may be employed. When the commutator is at rest (Figure 36) the
rotating commutator brush remains connected with the conductor or circuit L'
through the axis. When the commutator rotates (Figure 37) its segments aro
connected with rings insulated from each other, brushes bearing on the said
segments and establishing the circuit with the wire of the electro-magnet. The
time during which the extra coils of wire are included in, or switched out of, the
circuit may be easily regulated for the required purpose by making the parts of the
commutator of different sizes.
Article 24th. Another device for increasing the effect of the electro-magnets is
shown in Figure 38. Different spirals are wound laterally to each other on the
coro of the electro-magnets NS. These spirals are all in connection on one side
with the circuit L and on the other side with insulated metal pieces having a
brush to bear upon them which brush is connected with L, and conducts the
current onward. On moving L, either by giving the same a reciprocating, or, if
the metal pieces be arranged in a circle, a rotary movement, the current will flow
through one after another of the spirals, and thus the effect of the current after
having been concentrated for a short distance is conducted over the electro-magnet.
A somewhat different device for this purpose is shown in Figure 39.
Article 25th. The above described devices for electro-magnets may be employed
for any form of magnet. The right of using the forin shown in Figures 40 and 41
is reserved by the inventor and for all other manners of winding likewise.
The construction is shown in Figure 40 in vertical section. Figure 41 being a
plan partially in section on the line e, f, Figure 40. The manner of winding
around the more or less long cores Sa, Nb, appears clear from Figure 41, while
the surrounding iron shell a cbd receives the power of the wire coils which
otherwise would escape ontwardly. It will be seen from Figure 40 that the coils
of wire will also cause a direct induction of the armature rotating between the
poles N S. The blocks attached to the poles may be more or less large or may be
dispensed with, altogether. By reason of the direct induction produced by the
wires, cylindrical armatures without an iron core may also be used with this

page_text: construction. By reducing the length of one of the electro-magnet cores the form
indicated in Figure 40a is obtained which needs no further explanation.
Article 26. In large dynamo-electric machines the construction is rendered
very difficult if it is desired to employ only one large electro-magnet of the usual
kind. Several electro-magnets co-operating or working together are therefore
employed. Assuming two electro-magnet cores to be placed side by side as shown
in section in Figure 42 then the circuit will be as indicated by the arrows. It
will be seen from this, however, that the parts of the current between a and b will
exactly neutralize each other and thus be lost. The same also applies in the case
of a different section of the cores. In order to overcone this difficulty and at the
same time allow of dividing the machine, the electro-magnet is constructed as
illustrated in Figure 43 the core being composed of different parts and the wire
wound on several separate bobbins. The planes of division of core and wire
respectively must be placed rectangularly to each other as the division must be
made parallel on the magnetic axis. This arrangement may also be employed with
the construction as in Article 25th.
Article 27th In order to permit the current of the series dynamo-electric
machine to be regulated in case of an unvarying rotary speed of the induction
armature, one or more parts of the wire are so arranged on the electro-magnet
as to allow of their being alternately included in, and switched out of, circuit
according to circumstances. The power of the electro-magnet being thus varied,
the same power of current may be obtained under different circunstances.
The wire of the electro-magnet is included in, and switched out of, circuit in a
munner similar to that described in article 23rd, with this difference, however, that
the commutator brush is moved or shifted only when regulation becomes necessary,
this being done either by hand or automatically by the current. For this last
mentioned arrangement in case of weak currents and when only one change of
contact is necessary, "an electro-magnet with armature actuated by the current
or any similar apparatus may simply be used. For strong currents a governor
such as shown in Figure 44 may be employed, the same being actuated through
the current of the machine itself by means of an electric motor M. The change in
the speed of the motor, in consequence of a cbango in the intensity of the current,
produces the desired motion of the contact lever a, b, by means of the governor.
The current may also be utilized in an entirely indirect manner for engaging
and disengaging a clutch in which case any motor (the same one which actuates
the machine) produces the movement of the commutator brush. Thus a wire coil,
having an iron core NS as shown in Figure 45 and having the current to be
regulated passing through it, is made to actuate an elbow lever which shifts a
clutch c laterally in either direction. Thus a rotary motion in one or the other
direction is transmitted to the shaft ab by means of so-called reversible conical
gear-wheels through the shaft ƒ actuated by the motor. The shaft ab in turn
causes a contact lever to move after the manner of the shaft a, b shown in
Figure 44, the shaft a b Figure 45 remaining stationary while the current has its
proper power, but being put in motion as soon as the least change occurs until the
proper intensity of current is re-established by switching wire into or out of
circuit on the electro-magnet. Where it is desired only to keep derived currents,
instead of the entire current of the machine, constant, the motor M Figure 44, or
the wire coil N S, Figure 45, must be included in a derived or branch circuit.
According to the well known law of Kirchhoff the current in the other derived
circuits is thereby regulated likewise.
Article 28th. A steady or continuous current may also be obtained by means
of the device hereinafter described, the rotary speed of the armature being uniforin.
That is to say, two wires are wound on the electro-magnet. The resistance of
these wires and the connection with the induction armature and the outer circuit
is established differently according to circumstances, as will be seen from the
following description.
A dynamo-electric machine is indicated by the diagram Figure 46, the circle

page_text: representing the induction armature and the two zig-zag lines the wires of the
electro-magnet, a heavy and a light line being employed to distinguish the two
wires.
The Figures must be considered as examples only; thus for instance the electro-
magnet core may be surrounded simply by one continuous wire coil instead of two.
The two wires may be wound together or each wire may be wound into one or
more coils which can be attached to the electro-magnet core close together or one
above another. The manner in which the winding is effected will depond upon
sundry secondary considerations, as for instance upon the best means for securing
the necessary cooling or the proper insulation. For this purpose the same
principles must be applied which govern all other induction apparatus. Thus
two wires, in which a great difference of tension may be produced, must not bo
wound in such a manner as to admit of their touching one another, but each must
be wound to form properly insulated coils.
Several electro-magnets may also influence one or more induction armatures, and
in this case all must be wound in such a manner as to have the same magnetic
power among each other during the same force of the current.
In regarding each wire of an electro-magnet as a whole there will be but two
methods possible of connecting the same with the circuit, Figures 46 and 47.
Another, which lies between the two and consists in dividing the wire R₁, will be
referred to hereinafter. The letters of reference are to be understood as follows:-
I and as signifying the intensities or strength of the current, R and 7 the resistance
(for the wires of the electro-magnet both sides together) while E indicates the
electro-motive force of the induction armature.
Article 29th Assuming a number of apparatuses to be actuated by the current
from the machine and connected in multiple arc as it is termed. Let it be supposed
that in the diagram Figure 46 of the current, one of the said apparatuses be
indicated by ₁₁. Now according to the well known laws on derived or branch
circuits or on the division of circuits, this gives

page_text: AC
the other hand by a simple geometrical construction to find the corresponding
curve o a bif A and B (Figure 50) be given. For this purpose the line AB is
drawn, and the point C is chosen so that is equal to V, whereupon the line.CP
B.C
is drawn; the points of intersection a and b of this line with the vertical lines AI
and BI, will then lie in the curve looked for.
Article 31. The winding for a dynamo-electric machine giving the curve o ab
may now be easily found from the experiments which resulted in the curves
Figure 49. Now, by providing the electro-magnet in such a machine with an
additional circuit ir, being taken of such size as to obtain at I, the electro-
motive force AI, then the electro motive force obtained at I, according to the last
article, must be B. I. A B now being taken equal to A B in Figure 48, the
current i, in a derived circuit r, must be constant according to what has been said
regarding the said Figure in article 29, at least it must have the same value at I
and I. It follows, however, that the current is equal in every other derived
circuit, likewise, (formula 2). Now if in the second wire of the electro magnet i。 r.
were equal to ₁r, then the required intensity would just be obtained in the same
by connecting the wire ends with a and b, Figure 46. As a general rule this will
not be the case, but it will be easy to decide on a different winding ir producing
the same effect and conforming with the formula (2). Suppose u and u to be tho
number of windings desired to be found and the number of windings already
known respectively of and then i u must be
= i to
This equation with (2) is not sufficient for finding the three unknown
quantities ir u. A condition must, therefore, be employed. As such we may
assume that the developement of heat i'r for each unit of quantity of the wire
shall not exceed a certain amount. Now, if the winding be effected according to
this, the wire r may simply be connected with a and b according to Figure 40, in
order to obtain therein the correct intensity i, thus producing the constant of i̟, aš
previously explained.
Article 32nd. Now, as it is desirable to have the line of the electro-motive forco
coincide with the straight line between A and B, Figure 50, the decrease of A a
(I being on the increase) must not take place evenly, but more rapidly at the
commencement than towards the end. This really does occur and is due to the
stationary condition of the commutator brushes, the latter, being arranged in the
most favorable position for the strongest currents, though it is only for the
purpose of preventing sparks and therefore they are not properly adjusted for-
weak currents. An increase of the electromotive force thus results from this
improved position for stronger currents, opposing the decrease of A a from other
causes, that is to say, reducing the same.
It will thus clearly appear that, when the machine is able to supply the
electro-motive force B. I b, the electro-magnet in the case of the electro-motivo
force being b I, must be far from being saturated, thus corroborating the supposition
article 30th that only the commencement of the curve o ab need be taken into
consideration.
Article 32zd As to the second diasmom of
At
37

page_text: =
with R and R, it will be seen that in this instance the electromotive force is but
inconsiderably larger than according to formula (1). The value of i however, is
variable. Previously ir was = ₁₁r, and now, according to formula. (4), i r
is+I, R₁, which yields a much greater intensity when. I, is large, thus
causing an increased électromotive force likewise. This will most readily be seen 5
from an example in figures by assuming R to be as in a common dynamo-electric
machine and R, equal to one half the resistance of the electro-magnét, as there are
two wires in this case. Assuming
R to be =
R₁₂ =0.5 Ohms, = 20 Ohms, ₁₁ r₁ = 50 Volts, and
I₁ = 20 Ampères equal to I in formula (1),
we have that which generally prevails in the machine commonly employed. The
electromotive force for diagram Figure 46 will thus be found equal to 70 according
to formula (1) and according to formula (6) equal to 71, 5. Furthermore, we have
in the first case ir = 50, in the second case = 60. This increase of the
current will certainly raise the electro-motive force from 70 to about 71. 5. 1
Means are thus given for increasing the electromotive forco at B Figure 50, if the
machine fails to supply the requisite power, by connecting the wire with the
wire R, of the electro-magnet, not at a and b Figure 46, but closer to the induction
armature towards a b Figure 47.
Article 34th. It is well understood that in deriving currents such as i₁, they need 2
not exactly issue from the points a and b. Main wires may be attached to a and b
the branching circuits being connected with the same in case of the main wires
having but a low resistance. When it is desired, however, to first conduct the
current in an undivided state so far onward that the resistance of the circuit is no
longer to be neglected, then what has been said with reference to diagrain Figure 46 2
may also be applied in this case, it being necessary only to shift the connection a
and b to where the branching commences.
The machine may, however, be also adapted for this case without the said double
circuit, that is to say, without the said circuit and return circuit.
By adding at R in formula (6) the resistance of the outer circuit, it will be seen 3
that principally only in case of large I, the electro-motive force will now become
greater than before stated. Now this may be effected, as already shown, by
changing the connection of r with the wire R₁ of the electro-magnet.
•
Article 35th. If the apparatuses actuated by electric machines be all enclosed in
the main circuit (connected in series), a constant intensity of current independent 3
of the number of apparatuses enclosed in the circuit, that is to say, independent of
the outer resistance, is desirable, Thus there is in Figure 47 but one connection ?,
the resistance of which, however, is variable, while the current ₁ = I₁ is to be
constant.
'
Formulas (3) and (5) show
EIR+(R + r)
(7).
Here also E graphically expressed as the function of i-shows-a-straight line, as
Figure 48, because I, is to be constant. The same demonstration and derivation
as in articles 29, 30, 31 and 32, may be inferred, it being necessary only to exchange
R₁ for r, and vice versa.
The same conclusions are arrived at, and; the-two-wires of the electro-magnet
ir=i+1, R₁ = i (r₁ + R₁).....

page_text: If, therefore, r₁, be large, then i will in both cases be about equal, but in
Figure 46 the current in R, will be perceptibly larger, because i has also the largest
value and I is = i + 4. In the case of a low value for i, it will hardly be of any
consequence for the current in R; which of the two kinds of circuiting is used. If,
therefore, in the arrangement as shown in Figure 47, the electro-motive force for a
high value of r₁, becomes too small, it will be. necessary only to change the
connection of 7 with R, in the direction towards a b Figure 46:
Article 36th. The construction with two wires of an electro-magnet is also very
useful in galvano-plastic machines, because not only does the intensity of current
for each piece maintain the correct standard, whatever number of pieces may be
suspended in the same bath and whatever number of baths may be enclosed in the
circuit, but also the reversing of the poles of the electro-magnet does not take
place as easily here as in the common machines, and may under certain conditions
be entirely avoided. For this purpose it is only necessary that in case of counter-
current the magnetizing effect of r should be greater than that of R₁. This. may
also be made the main condition, a sufficient regularity of current being generally
still attainable.
For machines used for experimenting in laboratories, this device is also very
useful. As is well known, the common dynamo-electric machine is very sensitive
to changes in resistance and yields hardly anything above a certain quantity. The
magneto-electric machine is, therefore, justly preferred.
With the manner of
winding the electro-magnets as above described, however, the machine may be used
similarly to a common galvanic pile, presenting, at the same price and weight, this
advantage over the magneto-electric machine of having much more effect.
For an electric motor the device above described is also very practical in a great
many instances,
When there is a variable speed of rotation, for instance, the
counter-acting electromotive force of the motor, and consequently the intensity of
the current are variable likewise. Thus in a common machine the electro-magnet
will, under great speed, either receive too little current, or under small speed, too
much. This may be prevented by the peculiar manner of winding the electro-
magnets, as it will be easily seen, that i increases when I becomes weaker, and
vice versa. There is no difficulty in ascertaining and R, for given proportions, as
every export in electric matters will be able to do this at once, the more so since
an electromagnet of approximately constant strength (this being entirely sufficient)
may easily be attained after a few experiments, with different manners of winding.
Article 37th-The regulating device as per article 27th, may also be combined
with the above described manners of circuiting the two wires of the electro-magnet.
The arrangement may then be applied either to both of the wires of the electro-
magnets or to only one of them. The connection of r with R, in a and b, Figures 46
and 47, instead of being rigid may also be made so as to allow of being shifted
along R₁, the electro-motive force thereby being changed as shown. R₁ is then
constructed of different parts, these being connected with contact pieces insulated
from each other. A brush connected with r may be caused to move reciprocally
across the said contact pieces. The operation may be after the manner described
in article 23 and may be automatic as in that case.
The devices referred to in articles 23 and 24, may also practically be employed
with two electro-magnet wires, either for one of the wires or for both.
Having thus fully described the the said invention as communicated to me by my
foreign Correspondent and the manner of performing the same I wish it understood
that I claim :-
:-
First. The method of winding the wire of induction armatures as above
described and as shown in the accompanying drawings, which method consists
essentially in dividing each solenoid into a number of spirals and connecting the
spirals with different parts of the commutator, substantially as, and for the purpose,
set forth.
Second. The construction of induction armatures as above described and as
AM— 1–11 1001 n 01 of the
So the fiel

page_text: Third. The devices for increasing the magnetizing effect of the current in
electro-magnets, either by alternately including in, and cutting out of, the circuit
parts of the wire of the electro-magnet, or by concentrating the effect of the
current on a short portion of the core of the electro-magnet and conducting it ovor
the said core.
Fourth. The construction of electro-magnets as above described and as shown in
Figures 40, 40, 41 and 43 of the drawings for the purpose specified.
Fifth. The above described devices, for regulating the electric current in series
dynamo-electric machines by including in, and cutting out of, the circuit parts of
the wire of the electro-magnet either automatically, directly or indirectly by
means of the current, or not automatically.
Sixth. The winding of the electro-magnet, in a dynamo-electric machine or an
electro-motor, with two wires connected in the special manner, and for the purposes,
above set forth.
In witness whereof I the said Henry Harris Lake, have hereunto set my
hand and seal this Tenth day of July in the year of our Lord one thousand
eight hundred and eighty three.