IMPROVEMENTS IN ELECTRO-MAGNETIC AND MAGNETO-ELECTRIC MACHINES
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by Henry Wilde at the Office of the
Commissioners of Patents, with his Petition, on the 6th December
1866..
I, HENRY WILDE, of the City of Manchester, Engineer, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN ELECTRO-MAGNETIC AND
MAGNETO-ELECTRIC MACHINES," to be as follows:-
My Invention consists, firstly, in an improved method of producing electricity
from electro-magnetic machines, which electricity may be applied to various
useful purposes. In this improvement any even number of cylindrical bars of
wrought iron are screwed into one of the faces of a disc of wrought iron at
equal distances from the centre of the disc, and at equal angular distances
from each other and parallel with the axis of the disc; round each of these
iron cylinders a quantity of insulated copper wire is coiled, and the extremities
of all the coils are joined together in such a manner that when a current of
electricity is passed through the coils, the cylindrical bars become powerful
compound electro-magnets, having alternately north and south poles; two of
these compound electro-magnets are mounted in a suitable framework of cast
iron with the centres of the discs in the same straight line. The cylindrical.

page_text: bars are so arranged as to have their respective polar extremities opposite to
each other, the north poles of the cylindrical bars of one disc being opposite to
the south poles of those on the other disc; between these two circles of
electro-magnets a wheel is made to revolve concentrically with the axes of the
discs, and on the periphery of this wheel are fixed as many electro-helices with
iron cores as there are cylindrical bars on one of the discs. The iron cores of
the electro-helices are fixed upon the wheel in the usual manner, and are at
the same distance from the axes of the discs, and at the same angular distance
from one another as the cylindrical bars of the compound electro-magnets, and
the axes of the iron cores are parallel and coincident with the axes of the
cylindrical bars of the compound electro-magnets.
When the compound
electro-magnets are excited by means of the electricity from a magneto-electric
machine or other source of electricity, and when the wheel which carries the
electro-helices is made to revolve by means of a steam engine or other motor,
the iron cores in their passage between the polar extremities of the compound
electro-magnets are magnetized in alternate directions, and the alternating
currents induced in the helices surrounding the cores are taken in the usual
manner from the bearings of the shaft which carries the wheel to which the
electro-helices are fixed, and the electricity so produced may be used for
working telegraphs for producing the electric light, and for other purposes.
My Invention consists, secondly, in an improved method of arranging the
commutators of magneto-electric or electro-magnetic machines when such
machines produce more than two currents for one revolution of the wheel
which carries the electro-helices. When the currents generated by these
machines are required to pass in one direction only, as is the case in electro-
decomposition, it has been customary to make the commutators of such
machines of as many segments as there are alternations of the current for one
revolution of the wheel. In the present improvement the commutator may be
a cylindrical one of the form shown and described in the Specification of
Letters Patent granted to me on the 25th of February 1863, No. 516, or it
may be of any form which inverts the current twice only during one revolution
of the commutator. On the spindle of this commutator. a pinion is placed,
which is driven by means of a toothed wheel keyed on to the end of the shaft
which carries the helices, and the number of the teeth in this wheel and of
those on the pinion on the commutator spindle are so proportioned that the
commutator changes the direction of the current as many times as the
magnetism of the iron cores of the electro-helices is inverted during one-
revolution of the wheel.
Instead of a cylindrical commutator being used for

page_text: changing the direction of the current a commutator formed of several flat
metallic surfaces insulated from and sliding over each other (as in the slide
valves of a steam engine) may be used, the necessary reciprocating motion
being communicated to the sliding parts of the commutator by means of an
eccentric fixed on the spindle driven by the pinion above mentioned.