IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by Peter William Willans at the Office
of the Commissioners of Patents on the 13th December 1883.
PETER WILLIAM WILLANS of Thames Ditton in the County of Surrey
"IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES
"
This invention has for its object improvements in dynamo electric machines.
For this purpose I form a dynamo electric machine with one or more circular
magnet poles or poles of same polarity arranged in a circle. In front of one or
between two such poles I cause coils of insulated wire or other form of conductor
to be revolved. The insulated conducting coils are wound around iron cores
preferably of iron wire. The cores carrying the insulated conducting coils are
mounted upon an axis in such manner that when the axis is revolved and the
coils are carried through the magnetic field those parts only of each coil cut the
lines of force from the magnet pole to the core as will cause one continuous current
to be induced through the coil whilst the lines of force are deflected by the iron
core in such a way that the other parts of the coil through which a current would
be induced in the opposite direction shall cut as few of the lines of force as is
practicable.
By doing this I am able to obtain a continuous current from coils of insulated
conductor without the use of any commutator or other appliance for changing
the direction of the current whenever as in other machines the wire passes from in
front of a North pole to in front of a South pole.
In the Drawings annexed I have shewn diagram views of various ways in
which the above objects may be accomplished.
In the diagram view Figure 1-A and B are two circular magnet poles of
opposite polarity facing one another. C is an axis (shewn by dotted lines)
concentric with the annular magnet cores-D are annular coils of iron wire carried
by the axis and at a tangent to it-E are coils of an insulated conductor embracing
the iron ring D. One side of one of these coils is in close proximity to one of the
magnet poles and one side of the other coil is in close proximity to the other
magnet pole. Any desired number of such iron rings D carrying conducting
coils may be mounted upon the axis C. The current induced in the conducting
coils when the axis is revolved may be carried off from them in any convenient
manner,

page_text: In the diagram shewn at Figure 2 the arrangement is practically the same
except that instead of separate annular rings D of iron the several coils E are
carried by an iron core of a zig-zag form.
In the Diagram shown at Figure 3 A is a magnet pole with a grooved recess
formed in its face-B an annular magnet pole of opposite polarity or it might be
an annular iron core carried by arms from the circumference of a wheel the axis of
which may be revolved in any convenient way. C are a number of coils of an
insulated conductor the parts of the ring B which lie between the arms.
The ring B carrying the coils C is partly received into the groove in the face of
the magnet pole A and can be revolved around its axis. The current thereby
induced in the coils can be carried off in any convenient manner,
In the diagram shown at Figure 4. A and B are the two poles of a cylindrical
magnet. Within it is a smaller cylindrical magnet having its poles placed in the
opposite direction and mounted upon an axis C by which it may be revolved.
Around the rings forming the pole pieces of the inner magnet are coils D of an
insulated conductor. The current induced. in these coils when the axis is revolved
may be carried off in any convenient manner.
Machines constructed in the above manner may be used either for producing
electric currents or for obtaining rotary motion from such currents.