Dynamo Electric Generators.
Year: 1899

page_text: Date of Application, 10th June, 1899-Accepted, 5th Aug., 1899
COMPLETE SPECIFICATION.
Dynamo Electric Generators.
We, JAMES NORMAN SMITH, Electrical Engineer, and WILLIAM ASAHEL JOHNSON,
Manufacturer, both of 134, King Street, West, in the City of Toronto, in
the County of York, in the Province of Ontario, Canada, 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; -
Our invention relates to improvements in dynamo electric generators of the in-
ductor alternator type and the object of the invention is-first-to design à
machine of this class, which may be installed at a minimum expense and in which
a very close regulation will be produced and-secondly-to improve the con-
struction of the machine, so as to produce an evenly balanced magnetic flux in
the magnetic circuit and thus avoid to a great extent the hysteresis losses and
consequent heating and it consists essentially first-in the multiple method of
connections hereinafter described and--secondly-in making the machine of the
two circular field coil type as hereinafter more particularly explained.
Fig. 1, is a side elevation partially in section and broken away to exhibit the
construction of our generator.
Fig. 2, is a cross section on a line with the shaft.
Fig. 3, is a side view showing one multiple method of connections.
Fig. 4, is a similar view showing an alternative view of the multiple method
of connections.
In the drawings like letters of reference indicate corresponding parts in each
figure.
A is the frame, which is made of cast steel or other suitable metal. A' are two
field or exciting coils held in position by the frame A. B are laminated punch-
ings of steel or other suitable metal held together by the clamping plates E E
of steel or other suitable metal, such punchings and clamping plates being bolted
together by insulated bolts C. The laminated punchings B have projecting teeth
or poles on which are placed the armature coil or coils D, the number of pro-
jecting teeth or poles being governed by the class of current required from the
machine viz. single or multiphase and the number of alternations of current.
The number of armature poles or teeth can be from two to any number. Between
the frame A and armature laminations B a space F is left, the area of the same
being governed by the work the machine may be called upon to perform, the
space acting as a ventilating duct and the area of the space effecting the mag-
netic qualities of the generator.
We show two exciting coils A'A' which have a position peripherially outside
the armature coils D D and next the frame A and laterally outside the armature
laminations B.
GG are air ducts in the frame, which are provided to allow of the circulation
of the air caused by the revolving of the inductor H. Air ducts X are also pro-
vided in the laminations B in order to allow of the circulation of the air from the
inductor H to pass to the ventilating duct or space F between the frame A and

page_text: the laminations B. The frame A is also provided with air ducts R, (see dotted
lines in Fig. 1 and full lines in Fig. 2) connecting the space F with the outside
air.
The inductor H or rotating part of the generator is made of steel or other suit-
able metal. P is the hub of the inductor, which is provided with a rim P, in
an annular recess P2 of which are attached the laminated punchings I of steel
or other suitable metal, which are held in place by the dovetails i fitting in
the corresponding grooves p in the rim. The punchings or laminations I are
further heid in place in the annular groove, formed by the flanges L L, by the
bolts M. Both the hub and flanges are provided with air ducts to allow of the
air being drawn in and forced by the inductor punchings I through the ducts G G.
The different air spaces hereinbefore described are made of such a size as is
governed by the class of work the generator is called upon to perform.
The method of connecting the armature coils DD is shown in detail in Figs. 3
and 4, the number of the coils on each pole being governed by the class of work
required, which may be single or multiphase. In case of sixteen poles as shown
in the drawings and two armature coils per armature pole as shown in Fig. 3,
the order would be from any one coil on one armature coil to any other armature
coil on any other armature pole, whether lying next to or removed in number
of poles and in case of three or more armature coils per armature pole as shown
in Fig. 4, the same order would be required viz. to connect from one coil to any
other coil either on its own pole or any other pole. The number of poles or
armature projecting teeth may be either an odd or even number governed by the
class of work required.
It will be seen from this description that this multiple method of connections
has the advantage of a multiphase effect as to regulation, with a single phase
machine, and a corresponding advantage in working over the ordinary coup-
lings in a multiphase machine. In the general construction of the machine we
also have a great advantage over all previous types by reason of the two circular
field coil type with the evenly balanced magnetic flux, thereby secured in the
magnetic circle of the machine as we thus avoid to a great extent the hysteresis
losses and consequent heat.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is
-
1. In a dynamo electric generator of the inductor alternator type, the combi
nation with the inductor and the two field exciting coils suitably held in the
frame, of the armature provided with a plurality of projecting teeth or poles
and a plurality of coils on each pole connected to one another in series as shown
and for the purpose specified.
2. In a dynamo electric generator of the inductor alternator type, the combi-
nation with the inductor and frame, of the laminated punchings, the two field
or exciting coils located one on each side thereof and the armature comprising
the laminated projecting teeth or poles provided with suitable armature coils
suitably connected as and for the purpose specified.
3. In a dynamo electric generator of the inductor alternator type, in combi-
nation with the inductor and frame and the laminated punchings, the two field
or exciting coils located one at each side thereof, and the armature comprising
a plurality of laminated projecting teeth or poles and a plurality of coils on
each pole connected to one another as shown and described.
4. In a dynamo electric generator of the inductor alternator type, in combi-
nation with the inductor and frame and the laminated punchings, the two field
or exciting coils located one at each side thereof and the armature comprising
a plurality of laminated projecting teeth or poles, a plurality of coils on each
pole connected to one another, the air ducts passing through the faces and sides
of the frame, the annular spaces surrounding the laminated punchings in the

page_text: frame, the air spaces extending through the laminations, the air spaces sur-
rounding the inductor and the air ducts leading through the flanges of the
inductor as shown and for the purpose specified.
5. In a dynamo electric generator of the inductor alternator type, the combi-
nation with the inductor, of the laminated punchings, the two field or exciting
coils located one at each side thereof and the encompassing frame extending to
the outside of each coil whereby a suitable path for the magnetic flux is pro-
vided and the armature comprising the laminated projecting teeth or poles pro-
vided with suitable armature coils suitably connected as and for the purpose
specified.
1000
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicants.