Year: 1886

page_text: I RANKIN KENNEDY of the Electric Lamp Works 115 Woodside Road Glasgow
Lanarkshire Electric Engineer do hereby declare the nature of my Invention to
be as follows:-
This Invention has for its object the construction of new or improved electro
field magnets for being placed in circuit with the coils of the rotating armatures
in dynamo electric machines and electric motors for producing the magnetic or
galvanic field to induce by magneto electric induction the electric current in the
armatures of these machines and for other purposes; which improved field magnets
will require very considerable less wire in their construction prevent the loss or
diffusion of external magnetism or electricity save resistances in circuit, and
produce a more direct powerful and constant magnetic field with less expenditure
of energy than those heretofore in use.
My Invention is particularly applicable to that class of machines in which a ring
armature of the flat type.or disc form is used, and the magnets for producing the
magnetic field have two or more poles; my new or improved field magnets being
of such a form, and the wire on them so situated, that all the magnetising effect of
the latter shall be useful in producing by magneto electric induction a powerful
electric current in the armature rotating between their poles. And the nature and
novelty of my Invention consists in constructing the field magnets of a broad
cylindrical outer enclosing ring or casing, preferably of soft or cast iron and closed
in at each of its ends by a disc or side cheek of similar material, on the outer sides
of which may be formed or secured bracketed bush bearings for carrying the
spindle and driving pulley of the armature and the commutator and other fittings
of the dynamo or motor; or all these may be carried on a separate frame outside
the casing. The side cheeks or discs have each on their inside surfaces one, two, or
more projecting preferably inclined or curved ribs or flanges which might be in the
form of a ring with radial flat faces to form the poles projecting out towards the
disc armature. Round the outer circumference of this ring beyond the poles is
wound a circular or cylindrical coil of wire which fills up the space between this
and the outer enclosing cylindrical casing on each side and ends. These ends with

page_text: their coils and projecting parts form the North and South magnets and poles on
each side respectively, of this new arrangement of electro or field magnet, and they
are so constructed that the projections or radial poles on the one disc or magnet is
placed opposite the hollow parts or centre space between the poles of the other that
is with two poles in each at right angles to each other; and the revolving armature
of the machine is mounted on its carrying spindle, between and close up to these
projecting parts or poles.
In dynamo electric machines or electro-motors constructed as described the
magnetic lines of force due to the new or improved electro or field magnets will be
all internally utilised and concentrated and increased at definite poles on the
rotating armature.

page_text: I, RANKIN KENNEDY, of the Electric Lamp Works, 115 Woodside Road, Glasgow,
Lanarkshire, do hereby declare the nature of my invention and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement in writing, reference being had to the accompanying
Sheet of Drawings and to the reference letters and figures marked thereon, that is
to say:-
This invention has for its object the construction of new or improved electro-field
magnets for being placed in circuit with the coils of the rotating armatures in
dynamo-electric machines and electro motors for producing the magnetic field to
induce by magneto electric induction the electric current in the armatures of these
machines, and which may also be used for other purposes.
And these improved field magnets will require very considerable less wire in
their construction, prevent the loss or diffusion of external magnetism, save
resistances in circuit, and produce a more direct, powerful, and constant magnetic
field, with less expenditure of energy than those heretofore in use.
My invention is particularly applicable to that class of machines in which a ring
armature of the flat type or disc form is used, and the magnets for producing the
magnetic field have two or more poles; my new or improved field magnets being
of such a form, and the wire on them so situated that all the magnetising effect of
the latter shall be useful in producing by magneto electric induction a powerful
electric current in the armature rotating between their poles.
And in order that the nature and novelty of my invention, and the mode of
putting the same into effect or practice, may be properly understood, I have
hereunto appended a Sheet of explanatory Drawings, in which the same reference
letters indicate the same parts in all the Figures where shown.
In these Drawings, Figure 1, is a longitudinal vertical section, of a dynamo
electric machine, or electro-motor, constructed in accordance with one arrangement,
and illustrative of the improvements of my invention; and Figure 2 is a corre-
sponding end elevation of the machine, showing the commutator in front and
armature behind; while Figures 3 and 4 are transverse vertical sections looking
from opposite ends of the machine, at right angles to Figure 1, Figure 4 showing
the lower part of the armature as broken way from its centre, and both Figures
showing the field coils and poles of my new or improved electro-field magnets.
Referring to these Drawings:-the nature and novelty of my invention consist
in constructing the field magnets of a broad cylindrical outer enclosing ring or
casing E, preferably of soft or cast iron and closed in at each of its ends by side
cheeks C, C¹ of like iron, on the outer sides of which are formed or secured
brackets C, C¹, carrying the bush bearings c, c, for carrying the spindle B, and
driving pulley B', of the armature A, a, by its eye pieces A¹, and the commutator A³,
with the wires a connected to it from the armature, with its current collecting

page_text: brushes d, on the disc arms d³, d², and other revolving fittings of the dynamo or
motor; or all these may be carried on a separate frame or sole plate outside the
casing. The side cheeks or discs C, C', have each on their inside surfaces one, two,
or more projecting preferably inclined or curved ribs or flanges which might be in
the form of a ring D, with radial flat faces D¹, to form the poles D projecting out
towards the disc armature A. Round the outer circumference of this ring D,
beyond the poles D¹, is wound a circular or cylindrical coil of wire D1, D2, which
fills up the space between this and the outer enclosing cylindrical casing E, on
each side and close up to the ends C, C³, leaving a space e equal to the width of
the armature between the coils D¹¹, D'. These ends C, C¹, with their coils D¹¹, D*,
and projecting parts D, D¹, form the North and South magnets and poles, on each
side respectively, of this new arrangement of electro or field magnets, and they are
so constructed that the projections or radial poles D¹, on the one disc C, and
magnet are placed opposite the hollow parts or centre of the space between the
poles D¹ of the other disc C¹, that is in this arrangement with two poles in each at
right angles to each other. The revolving armature A, a, of the machine is
mounted on its carrying spindle B¹, between and close up to these projecting parts
or poles D, D', on opposite sides of it.
In dynamo electric machines or electro-motors constructed as described the
magnetic lines of force due to the new or improved electro or field magnets
will be all internally utilised and concentrated and increased, at definite poles D¹,
on the rotating armature A, a.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
First. The new or improved construction of Electro-magnets, having their field
coils enclosed within a surrounding outer casing in a recess between this and their
radial face poles, for dynamo electric machines and electro-motors, or other
purposes, all substantially as herein described in reference to and shown in the
accompanying Drawings.
Second. The constructing of Dynamo-electric machines and electro-motors with
Electro-field magnets enclosed by a cylindrical casing (E) with two end discs or
cheeks C, C¹, having projections D₁ which form the magnetic radial poles sur-
rounded by their enclosed field coils of wire, the projections or radial poles (D¹) on
the one cheek C being opposite the flat or hollow parts of the other C₁, substantially
as herein described, in reference to and shown in the accompanying Drawings.
Third. In Dynamo-electric machines and electro-motors, the construction and use
of Electro-magnets for producing a magnetic field to concentrate and increase the
lines of magnetic force at definite radial poles (D¹) on each side of the rotating
armature (A) substantially as herein described, in reference to and shown in the
accompanying Drawings.