IMPROVEMENTS IN THE CONSTRUCTION OF DYNAMO ELECTRIC MACHINES EMPLOYED FOR GENERATING ELECTRIC CURRENTS
Year: 1879

page_text: LETTERS PATENT to John Formby, of Formby, in the County of Lancaster,
Gentleman, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION
OF DYNAMO ELECTRIC MACHINES EMPLOYED FOR GENERATING ELECTRIC
CURRENTS."
Sealed the 8th August 1879, and dated the 13th February 187
PROVISIONAL SPECIFICATION left by the said John Formby at the Office
of the Commissioners of Patents on the 15th February 1879.
JOHN FORMBY, of Formby, in the County of Lancaster, Gentleman. " IM-
PROVEMENTS IN THE CONSTRUCTION OF DYNAMO ELECTRIC MACHINES EMPLOYED.
FOR GENERATING ELECTRIC CURRENTS."
Magneto and dynamo electric machines designed for producing powerful electric
currents do according to their present arrangement work at a disadvantage, inasmuch
as the full power of the current generated by such machine is from the following
causes not transmitted therefrom:-
First. The magnetic drag between the fixed and moving parts of the machine
necessarily resists the motion and absorbs a large percentage of the power employed
for driving same.
Second. Heating, which is caused partly by molecular resistance in magnetisation
and demagnetisation, partly by the attempt to work the machine beyond the
saturation point of the cores of their magnets.
Third. The loss of current and wear and tear of parts caused by the use of
complicated collectors and commutators which by the constant "make" and "break"
of current inseparable from their use cause sparks and burning of connections.
The object of this Invention is the construction of a dynamo electric machine
which will overcome these difficulties, the arrangement and working of which may
be thus described
I wind six, eight, or more straight coils on surfaces of wood or other suitable
nonconducting substance and arrange them in a circle around and parallel to the
axis of the machine, braced with metal when necessary, and in such a manner that
their ends or poles are in the plane of a circle. These straight coils are supported
in upright frames, and opposite to their ends or poles two circular revolving coils
are placed, which said coils are also wound on wood or other suitable nonconducting
substance, as herein described.

page_text: Immediately outside these circular revolving coils there are two other circular
fixed coils wound on rings, the whole of these rings, whether revolving or fixed,
are wound with continuous coils or joined as such.
Two gun metal or other conducting concentric rings on each revolving coil form
the-media-for-the-passage-of-the electric current through these circular revolving
coils, each gun metal ring_being_in_contact_with one end of the coil.and bearing
against a wire brush collector, or if desired other forms of-collectors-may-be-used.
On the top of the machine, or in other convenient and suitable position, a terminal
-board, or a series_of_terminals,-is-or-are-arranged,-to-which-the-ends-of-cach-coil-
requiring change of electric connections are led, and where also the connections
are made either for tension, quantity, number of circuits, or otherwise as may be
-desired:
The straight coils parallel to the axis of the machine are so arranged that all
their north-poles act on one of the aforesaid revolving rings, and all the south-poles
on the other, or may be connected so in part.
The action and working of the machine may now be described as follows:-
Before starting the connections are to be made with the terminal board or terminals
in such a manner that each revolving ring will be in contact with at least two of
the straight. coils, that is, if all such straight coils are not in circuit. Immediately
the machine is set in motion the residual magnetism latent in the iron or steel of
the frame work-sets up a slight current in the circular revolving coils which cut
through its magnetic field; this current is passed through the straight coils in the
same closed circuit forming a fresh magnetic field opposite the poles of the straight
coils, thereby strengthening the current which thus goes on accumulating in quantity
or tension. The fixed ring coils are for the purpose of increasing the current in
quantity. By the large induction surface which the fixed ring coils present to the
revolving rings the former provide means for increasing the number of currents and
may be variously joined.
The supplementary currents being wholly generated by induction, as every ring
fixed or moving is in circuit with several of the straight coils or otherwise.
The currents generated in the fixed rings and straight coils react on the revolving
rings, and so fulfil their original and most important function. The current or
currents required for external work are collected from different parts of the machine
at will, or the whole may be worked as one circuit, the exterior circuit in that case
being completed before starting the machine.

page_text: The straight coils a, a, parallel to the axis of the machine are so arranged that
all their north-poles act on one of the aforesaid revolving rings d, d, and all the
south-poles on the other, or may be connected so in part.
==
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The action-and-working of the machine may now be described as follows
Before starting, the connections are to be made with the terminals m, m, (seen in
plan at Fig. 3) in such a manner that each revolving ring d, d, will be in connection
with at least two-of-the-straight coils a, a, that is, if all the straight.coils-are-not-in-
--the-same-circuit.
Immediately the machine is set in motion_the_residual-magnetism-latent-in-the-
iron or steel of the frame work sets up a slight current in the circular revolving
coils d, d, which cut through its magnetic field. This current is passed through the
straight coils in the same closed circuit, forming a fresh magnetic field opposite the
poles of the straight coils a, a, thereby strengthening the current which thus goes
on accumulating in quantity or tension. The fixed ring coils e, e, are for the purposo
of increasing the current.
By the large induction surface which the fixed ring-coils e, e, present to the
revolving rings d, d, the former provide means for increasing the number of currents
and may be variously joined.
The supplementary currents are wholly generated by induction, as every ring
fixed or moving is in circuit with several of the straight coils, or otherwise.
The currents generated in the fixed rings e, e, and straight coils a, a, react on the
revolving rings d, d, and so fulfill their original and most important function. The
current or currents required for external work are collected from different parts of
the machine at will, or the whole may be worked as one circuit, the exterior circuit
in that case being completed before starting the machine.
Having now described the nature of my said Invention, tegether with the
manner of performing the same, I would wish it to be particularly understood in
conclusion that what I claim as new and as of my Invention is,—
The construction of a dynamo-electric machine combining the novel arrangement
of parts herein substantially described and set forth, and illustrated in the Drawings
annexed, to be employed for producing powerful electric currents.
In witness whereof, I, the said John Formby, have hereunto set my hand and
seal, this the Eighth day of August, in the year of our Lord One thousand
eight hundred and seventy nine.
Witness,
LONSDALE FORMBY.
JOHN FORMBY. (L.S.)