IMPROVEMENTS IN DYNAMO-ELECTRIC MACHINES
Year: 1876

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
DYNAMO-ELECTRIC MACHINES." A communication from abroad by Dieudonné
Francois Lontin of Paris, France.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 31st January 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
IMPROVEMENTS IN DYNAMO-ELECTRIC MACHINES."
"
This Invention relates to improvements in the construction and operation of
dynamo-electric machines, and consists,-
1st. In constructing dynamo-electric machines in such manner that the inducing
electro-magnet or electro-magnets shall have rotary motion, while the induced coils
or helices remain stationary, which is the reverse method of working to that of
ordinary machines of the kind.
2ndly. In increasing the length of the inducing electro-magnets (of an ordinary
dynamo-electric machine working in the usual way) sufficiently to enable one or
more conducting wires to be placed thereon, from the ends of which are taken the
current or currents produced.
By the use of these two means I obtain a result of great importance as employed
separately or combined; they enable me to take the currents in the machine as I
may desire, whether for tension or for quantity, whether wholly or partially without
employing any collector for the currents alternate in direction, as will be readily
understood since the induced portions are not movable.
As an example of the first part of the Invention, I have illustrated in Figure 1 of
the accompanying Drawing a dynamo-electric machine formed of one or more induc-
tion wheels A, A, revolving in front of the poles of simple or multiple electro-magnets
B, B, B, B, but with the modification indicated under the same head of the Inven-
tion. I have an induction wheel; which, instead of being induced will be inductor,
and electro-magnets which instead of being inductors will be induced. In this
way the induced portion being fixed instead of movable the currents may be dealt
with in any manner desired without the use of a collector or contact ring. For
example, in a machine having 50 induced portions, there would be 50 sources of

page_text: electricity capable of employment separately or collectively.
One special appli-
cation of such a machine is that of producing with the same machine any desired
number of electric lights.
The machines on the principle described under this head of this Invention would
be magnetised from a special source, or by a portion of the machine current itself
reversed for this purpose.
In carrying out the 2nd part of this Invention I take for example one of my
ordinary dynamo-electric machines, the electro-magnets of which are made with
longer cores than usual, and I apply upon this additional length of core one or more
conducting wires, from whose ends I collect the electricity there developed. This
arrangement, shown in Figure 2, enables me to obtain at once with the same machine
both currents, invariable in direction (from the induction wheel), and alternate
currents from the electro-magnet or magnets, or a current from one of these sources
only as desired. A. is the induction wheel; B, B, the coils of the electro-magnets;
and C, the fixed induction coils or helices with alternate currents.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Melville Clark in the Great Seal Patent Oflice on the
.22nd July 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middle-
sex, Patent Agent. "IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES." A commu-
nication to me from abroad by Dieudonné François Lontin, of Paris, France.
This Invention relates to improvements in the construction and operation of
dynamo-electric machines, and consists,-
1st. In constructing dynamo-electric machines in such manner that the inducing
electro-magnet or electro-magnets shall have rotary motion, while the induced coils
or helices remain stationary, which is the reverse method of working to that of
ordinary machines of the kind.
2ndly. In increasing the length of the inducing electro-magnets (of an ordinary
dynamo-electric machine working in the usual way) sufficiently to enable one or
more conducting wires to be placed thereon, from the ends of which are taken the
current or currents produced.
By the use of these two improvements I obtain a result of great importance
since employed separately or combined; they enable me to take the currents in the
machine as I may desire, whether for tension or for quantity, whether wholly or
partially without employing any collector for the currents alternate in direction, as
will be readily understood since the induced portions are not movable.
As an example of the first improvement I have illustrated in Figure 1 of the
accompanying Drawing a dynamo-electric machine formed of one or more induction
wheels A, A, revolving in front of the poles of simple or multiple electro-magnets
B, B, B, B, but with the modification iudicated under the same head of the Inven-
tion. I have an induction wheel, which, instead of being induced will be an inducer,
and electro-magnets which instead of being inducers will be induced. In this way
the induced portion being fixed instead of movable the currents may be dealt
with in any manner desired without the use of any collector or contact ring. For
example, in a machine having 50 induced portions, there would be 50 sources of
electricity capable of employinent, either separately or collectively. One special
application is that of producing with the same machine any desired number of
electric lights.
The machines on the principle described under this head of the Invention would
be magnetized from a special source, or by a portion of the machine current itself
reversed for this purpose.
In carrying out the 2nd part of this Invention I take for example one of Lontin's
ordinary dynamo-electric machines, the electro-magnets of which are made with

page_text: longer cores than usual, and I apply upon this additional length of core one or more
conducting wires, from whose ends I collect the electricity there developed. This
arrangement, which is shown in Figure 2, enables me to obtain at once with the
same machine both currents invariable in direction from the induction wheel, and
alternate currents from the electro-magnet or magnets, or a current from one of
these sources only as desired. A, A, is the induction wheel; B, B, the coils of the
electro-magnets magnetised by said wheel; and C, the fixed induction coils with
alternate currents.
"J
I would observe that in cases where but a relatively weak quantity of electricity
is required, steel magnets may be employed as inducers in place of the electro-
magnets. In this manner currents may always be obtained direct without the use
of any contact ring. For example, the arrangement of an ordinary "Alliance'
machine may be reversed, that is to say, the steel magnets may be mounted on the
revolving axis in place of the discs, and the induced coils fixed upon the framing,
whereby, owing to the increased number of induced coils it is possible to employ,
a larger quantity of electricity is obtained. A machine thus arranged would be
similar in principle to Figure 1, and A, A, would represent the steel magnets.
The currents produced may either be combined in one single current, as in the
ordinary Alliance machines, or by adopting the sectional arrangement herein-
before described, the electricity produced may be. divided into as many distinct
currents as possible.
Having described the nature of the said Invention and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is, the improvements herein-before
shown and described under the 1st and 2nd heads of this Invention, together with
the modifications and applications of the same.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set my
hand and seal, this Twenty-second day of July, in the year of our Lord
One thousand eight hundred and seventy-six.