Improvements in, Dynamo Electric Machines or Electric Motors.
Year: 1893

page_text: COMPLETE SPECIFICATION.
[Communicated from abroad by ROBERT LUNDELL, Electrician, and EDWARD
HIBBERD JOHNSON, Electrician, both of No. 44, Broad Street, New York
City, County and State of New York, United States of America.]
vib:
..
Improvements in, Dynamo Electric Machines or Electric Motors.
1, HENRY HARRIS LAKES of the firm of Haseltine,. Lake & Co., Patent Agents,.
45 Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:—
This invention relates to improvements upon a former Patent for dynamo electric
machines or electric motors dated the 17th day of May, 1892, No. 9365.
In the Patent referred to a single field inagnet coil was made to embrace the
armature coil, the axes of the two coils being inclined to each other, the effective
pole pieces of the field magnet being located in the angular space between the two
coils so as to overlap or extend past each other on opposite sides of the armature.
Such a structure however was adapted only to machines of a bi-polar nature, the
axial relation of the two coils referred to being such that it is impossible to
construct a machine with multipolar field poles.
The present invention therefore is an improvement upon the invention shown,
described and claimed in the aforesaid Patent to the extent that the arrangement
of the parts of the machine is such as to adapt it to multipolar construction. This
is effected by arranging the field magnet coil concentric with the armature coil so
that the effective poles of the field magnet core may be arranged in pairs to any
desired number around the armature and in the annular space between it and the
field magnet coil.
The invention will be fully understood by referring to the accompanying
drawings in which,
Figure 1 is a longitudinal sectional view of the improved. machine taken on
line 11, Figure 2, the armature windings, the armature shaft, its journal bearing,
the commutator, commutator brushes and circuit connections of the machine not
being shown, such matters being obvious to those skilled in the art and particularly
in view of the prior Patent above referred to..
Figure 2 is a transverse section taken through the body of the machine on
line 2-2, Figure 1, and as seen looking at Figure 1 from the left toward the
right.
The field magnet core is made preferably of two hollow cylindrical parts E
and F of magnetic material, the part F having one or more pairs of effective
field poles P P and the part E one or more corresponding pairs of similar
poles P¹ P¹ said poles P P of the part F being directly opposite each other and the
poles P P of the part E having a corresponding relation, as clearly shown
in Figure 2, the arrangement being such that when the two parts E and F of the
hollow cylindrical field magnet core are put together the field magnet poles P P
and P¹ P¹ will be arranged in pairs between each other and in the annular space
between the field magnet coil B and the armature D, the axes of the armature
and the coil B being co-incident with each other. The unwound laminated
arinature core D is shown in position and the field magnet coil B is also shown in
position, it being wound in a former or bobbin of the nature shown in Figure 1 so
as to give the best magnetic effects to the field magnet poles P P P P¹ located in
the annular space between it and the armature. When the field magnet coil is in
position and the parts are bolted together through bolt holes radially disposed
around the exterior of the cylindrical field magnet core all of the insulated wire

page_text: windings are fully protected from extraneous injury in the same manner as were
the like parts described in our prior Patent.
FF are ventilating holes for admitting air to the interior of the machine.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is :-
1. An electric motor or dynamo electric machine having a single field magnet
coil which encloses or surrounds two or more pairs of inwardly projecting field
magnet poles in combination with a rotary armature having its axis coincident or
parallel with the axis of the field magnet coil, said poles being located in the
annular space between the field magnet coil and the armature, "substantially as
described.
.
2. An electric motor or dynamo electric machine having a cylindrical enclosing
shell with two or more pairs of inwardly projecting pole pieces and a single field
magnet coil in combination with a rotary armature having its axis co-incident or
parallel with the axis of the field magnet coil, the inwardly projecting pole pieces
lying in the annular space between said coil and the armature, substantially as
described.
3. An electric motor having a single field magnet coil and an armature, the
axis of which is co-incident with the axis of the field magnet coil and two or more
pairs of inwardly projecting field magnet poles located in the annular space
between the field magnet coil and the armature, substantially as described.
4. An electric motor or dynamo electric machine having a hollow cylindrical
shaped field magnet core provided with two or more pairs of inwardly projecting
field magnet poles located in the annular space between a single field magnet coil
and the armature, said field magnet coil and armature being encased by a
cylindrical shell or drum and the armature sustained by a shaft co-incident with
the axis of the field magnet coil.
5. An electric motor or dynamo electric machine having a hollow two-part
cylindrical shaped field magnet core with two or more pairs of oppositely disposed
field magnet poles, a single enclosed field magnet coil having its axis co-incident
with that of the armature, said field magnet coil being wound in a former or
bobbin substantially of the shape shown in Figure 1 of the accompanying drawings,
the field magnet poles being located in the annular space between the field magnet
coil and the armature.
Dated this 24th day of January 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.