Improvements in Dynamo Electric Machines.
Year: 1895

page_text: Reprinted as amended in accordance with the decision of the Comptroller General
of 8th day of June, 1900.
Date of Application, 20th Dec., 1895
Complete Specification Left, 22nd July, 1898-Accepted, 22nd Aug., 1896.
PROVISIONAL SPECIFICATION.
Improvements in Dynamo Electric Machines.
We, VALERE ALFRED FYNN, Electrician to Messrs. Easton, Anderson & Goolden,
Limited, of Erith Iron Works Erith, in the County of Kent, and EASTON.
ANDERSON & GOOLDEN, LIMITED, of the same place do hereby declare the nature of
this invention to be as follows:
This invention has for its object to provide dynamo electric machines, (whether
alternating or direct, current generators, or motors,) which are economical in
construction and efficient in action, cool running being ensured.
For this purpose, the field, which is preferably stationary, (though a revolving
field may be employed) is not arranged with its alternating pole pieces all in one
plane transverse to the axis of the armature, but the pole pieces are set so that
they are alternately in different planes, the necessary space between them being
provided lengthwise of the armature. The pole pieces may be in any suitable
number in each series, and any number of series may be used side by side. A
single coil wound on a circular former is used for exciting. In case the field
has three, or four or more series of pole pieces, two, or three or more, coils may
be employed. The pole pieces may be laminated. All the legs, or projections,
on the one side of the exciting coil are say, north poles, and all those on the other
side are south poles.
The disposition enables all or any desired number of the wires or conductors on
the armature to be simultaneously exposed to the direct action of the poles, in a
four pole machine for instance, each pole will span 90° or thereabouts of the
armature circumference.
"
The neutral line can be thus made absolutely definite at no load" and, as soon
as a lead is given to the brushes, they can be made to come under the edge of the
next pole which then acts as a reversing pole, and thus the lead necessary is
greatly reduced.
<<
The
The body of the armature is composed preferably of a solid block of forged iron
cast steel, or cast iron, or like metal, although laminations or plates may be
employed therefor, if desired the diameters thereof being uniform or not.
body is provided with a collar" or equivalent stops on either side of the mid-
portion corresponding to the exciting coil of the field, and on each end of the
body outside this mid-portion are slipped a number of laminated iron annular
discs, or rings, to an extent or width corresponding to the poles of the field.
The outer diameter of these discs or rings is larger than the outer diameter of the
collar" or equivalent stops. These annular discs or rings are preferably slotted
to receive the armature winding, but the winding can be carried on the plain
edges of the discs or rings, or through holes therein.
26
The winding (which can be of any known or suitable kind, such as a drum or a
Gramme, winding for instance) can be done in the same way as on an ordinary
..

page_text: machine. Except the end connections all the wires, or conductors, constituting
the winding, run parallel to the axis, through the air space at the mid-portion
of the armature body, and over or through, the slots or hcles, in the laminated
annular discs, or rings, on each side thereof.
Thus the wires or conductors between the two sets of laminated discs, or
rings, of the armature are exposed to the air, and act as a sort of fan. The
action as a fan may be increased by projections from the armature body in the
space between the sets of laminated discs or rings.
It is important when using fields of the above description to reduce the air gap
to the minimum, but a certain amount of resistance is necessary in the magnetic
circuit.
This necessary resistance in the magnetic circuit is placed in a machine con-
structed according to this invention, either in some portion of the field or in
the armature itself.
The armature may be fitted with a commutator of the ordinary construction
or with a commutator with a vertical "face" to economize space.
When the machine has to be enclosed, as for instance for mine work, a circular
cover, carrying the bearings, can be applied to each side.
To ventilate this machine, though enclosed, openings can be provided in the
field body, outward of the exciting coil, and, in order to prevent an explosion,
should ignition of gas occur inside the machine, these openings can be partly,
or wholly, filled with fine wire gauze.
It is of importance that the amount of air enclosed should be as small as
possible, and to reduce this amount the gap between the poles on each side of the
exciting coil, can be filled with some suitable non-magnetic and light material.
The same general arrangement can be applied to dynamos and motors for single
phase and polyphase alternating currents as well as for continuous current
inachines.
In the former case it will be advantageous to construct the machine with a
stationary armature (constructed as described for the direct current omitting the
commutator) and a revolving field of the type described, the exciting coil may
either be stationary, or it may revolve with the field.
It is obvious that, without departing from the spirit of this invention, the
disposition of armature and field may be inverted or otherwise arranged with
respect to each other, and also that cither the field, or the armature, or both,
may be rotated and in any case the exciting coil or coils may be either stationary,
or may revolve. For instance an armature constructed with an air space and
two sets of laminated discs or rings, on either side of an air space, can be arranged
as an annular armature the field consisting of a revolving body with pole pieces
alternately in different planes transverse to the axis of rotation, and with an
exciting coil between the two series of pole pieces.
Dall this 2011.
T
100
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C.,
Agents for the Applicants.
We, VALERE ALFRED FYNN, Electrician to Messrs. Easton, Anderson & Goolden,
Jul., of Erith Iron Works, Erith, in the County of Kent, and EASTON
ANDERSON & GOOLDEN, LIMITED, of the same place do hereby declare the nature of

page_text: this invention and in what manner the same is to be performel, to be particularly
described and ascertained in and by the following statement:-
This invention has for its object to provide dynamo electric machines (whether
alternating, or direct current generators, or motors) which are economical in
construction and efficient in action, cool running being ensured.
For this purpose, the field, which is preferably stationary, (though a revolving
field may be employed,) is not arranged with its alternating pole pieces all in
one plane transverse to the axis of the armature, but the pole pieces are set so that
they are alternately in different planes the necessary space between them being
provided lengthwise of the armature.
The series of pole pieces in one plane are arranged opposite the gaps between
the pole pieces of the series in the adjacent plane.
The pole pieces may be in any suitable number in each series, and any number
of series may be used side by side. A single coil wound on a circular former
is used for exciting. In case the field has three, or four or more series of pole
pieces, two or three or more exciting coils may be employed. The pole pieces may
he laminated. All the legs, or projections, on the one side of the exciting coil
are, say, north poles, and all those on the other side are south poles.
The disposition enables all or any desired number of the wires or conductors on
the armature to be simultaneously exposed to the direct action of the poles in a
four pole machine for instance, each pole will span 90° or thereabouts of the
armature circumference.
66
The neutral line can be thus made absolutely definite at no load" and, as
soon as a lead is given to the brushes they can be made to come under the edge of
the next pole which then acts as a reversing pole and thus the lead necessary
is greatly reduced.
The body of the armature may be composed of a solid block of forged iron,
cast steel, or cast iron, or like metal although laminations or plates may be
employed therefor if desired, the diameters thereof being uniform or not.
The body is provided with a "collar" or equivalent stops on either side of the
mid portion, corresponding to the exciting coil of the field, and on each end of
the body outside this mid-portion are 'slipped a number of laminated iron
annular discs, or rings, to an extent or width corresponding to the poles of
the field. The outer diameter of these discs or rings is larger than the outer
diameter of the "collar" or equivalent stops. These annular discs, or rings, are
preferably slotted to receive the armature winding, but the winding can be carried
on the plain edges of the discs or rings, or through holes therein.
The winding, (which can be of any known or suitable kind such as a drum, or a
Gramme, winding, for instance.), can be done in the same way as on an ordinary
machine. Except the end connections all the wires or conductors, constituting the
winding, run parallel to the axis through the air space at the mid-portion of the
armature body, and over, or through the slots or holes in, the laminated annular
dises, or rings, on each side thereof. Thus the wires or conductors, between the
two sets of laminated discs, or rings, of the armature, are exposed to the air and
act as a sort of fan. The action as a fan may be increased by projections from
the armature body or collar in the space between the sets of laminated dises or
rings.
It is important when using fields of the above description to reduce the air
gap to the minimum but a certain amount of resistance is necessary in the
magnetic circuit.
This necessary resistance in the magnetic circuit is placed, in a machine con-
structed according to this invention, in some part of the magnetic circuit where no
leakage can take place, either in some portion of the field or in the armature
itself.
The armature may be fitted with a commutator of the ordinary construction, or
with a commutator with a vertical face to economise space,
"

page_text: When the machine has to be enclosed, as for instance for mine work, a circular
cover, carrying the bearings, can be applied to each side.
To ventilate this machine, though enclosed, openings can be provided in the
field body, outward of the exciting coil, and in order to prevent an explosion,
should ignition of gas occur inside the machine, these openings can be partly,
or wholly, filled with fine wire gauze.
It is of importance that the amount of air enclosed should be as small as
possible, and to reduce this amount the gaps, between the poles on each side
of the exciting coil, can be filled with some suitable non-magnetic and light
material.
The same general arrangement can be applied to dynamos and motors for single
phase and polyphase alternating currents, as well as for continuous current
machines.
In the former case it. will be advantageous to construct the machine with a
stationary armature (constructed as described for the direct current, omitting the
commufator) and a revolving field of the type described, the exciting coil may
either be stationary, or it may revolve with the field.
It is obvious that, without departing from the spirit of this invention, the
disposition of armature and field may be inverted, or otherwise arranged with
respect to each other, and also that either the field, or the armature, or both may
be rotated and in any case the exciting coil or coils may be either stationary, or
may revolve. For instance an armature constructed with an air space and two
sets of laminated discs, or rings, on either side of an air space, can be arranged as
an annular armature, the field consisting of a revolving body with pole pieces
alternately in different planes transverse to the axis of rotation, and with an
exciting coil between the two series of pole pieces.
Figure 1 of the accompanying drawings represents partly in end elevation and
partly in transverse section a four pole continuous current dynamo electric
machine made according to this invention, the exciting coil being omitted for
the sake of clearness. Figure 2 shews the same machine partly in side elevation
and partly in longitudinal section-the section being taken on the line 1-2
Figure 1, and Figure 3 is a longitudinal section on the line 3-4 Figure 1.
Figure 4 represents partly in end elevation and partly in transverse section on the
line 5-6, Figure 5 an alternate current machine constructed according to this
invention with a stationary armature and a rotary field. Figure 5 is a part side
elevation and part longitudinal section of the same. Figure 6 shews in side
elevation a direct current machine suitable for use in mines and like places it
being provided with ventilating openings covered with and containing wire
gauze. Figure 7 is a section through one of the ventilating openings shewing
the wire gauze therein.
In
Referring to Figures 1, 2 and 3 A represents the body of the stationary field
magnet of a direct current machine and B the rotary armature. The field has four
poles C, C arranged in pairs in different planes transverse to the axis of the
armature a space a being provided between the two pair of poles C and C
lengthwise of the armature in which space is arranged an exciting coil D.
each pole C C is a gap c to prevent a cross field being formed by the current
circulating through the armature conductors and tending to demagnetize the
poles CC. Each pole extends to about 90° of the circumference of the armature,
and the spaces d between the poles in each plane are preferably filled with some
non-magnetic and light material to reduce space for air as much as possible when
the machine is enclosed. This arrangement of the poles C C enables any desired
number of the wires or conductors on the armature to be simultaneously presented
to the direct action of the poles, and the neutral line can be made absolutely
definite at no load," and as soon as a lead is given to the brushes, they can be
caused to enter beneath the edge of the next pole which then acts as a reversing
pole and reduces the lead.
66
The body of the armature may be composed of a solid block of metal but it is

page_text: preferable to construct it, as shewn, of laminations or plates & reaching down to
the shaft B of the armature, a collar B3 being formed on or fixed to the shaft,
which collar separates the two parts of the armature coinciding respectively with
the two pairs of poles C and C2, gun metal discs I being interposed between the
sides of the collar B and the two sets of laminated plates b to form an additional
resistance in the magnetic circuit of the machine. The collar B³, may, if desired,
be built up of laminated discs. The plates bare of greater diameter than the
collar and have in their peripheries notches, or holes near their peripheries, to
receive the windings a² of wire, which windings cross the space between the two
sets of laminated plates as shewn in Figure 2, the portions of the windings in
the said space being exposed to air and acting as the vanes or blades of a fan to
distribute the air inside the machine. In the body of the field magnet, ventilating
holes are provided, through which air can circulate to keep the machine cool.
If the armature be provided with a commutator it will yield direct current, or
if provided with slip rings it will deliver monophase or polyphase alternate cur-
rents, according to the manner of winding and connecting. When the machine is
required for use in mines it is necessary to close the ends in casings, and to cover
the ventilating openings F in the body of the field magnet, with wire gauze and
also to place in the said ventilating openings wire gauze as shewn at f in Figures 6
and 7 to prevent explosions.
Referring to Figures 4 and 5 A is a rotary field and B a stationary armature
of an alternate current machine. The body part of the armature B is a solid
casting with ventilating openings therein, and provided with laminated
parts directly exposed to the action of the poles C and 2 of the field, an
exciting coil being arranged in the space between the said two sets of
poles CC. The poles C C may be solid or built up of laminated plates as shewn,
tir-gaps-or openings d² being provided between each two adjacent pole pieces of each
set, and the pole pieces of one set being arranged opposite the gaps-or openings
between the pole pieces of the other set.
The windings a² of the armature pass through holes e or notches in both laminated
parts , 2.
The field is divided by a brass or like metal plate A2, forming an
additional resistance in the magnetic circuit.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1st. A dynamo electric machine having the poles of the field arranged alternately
in different planes and gun metal discs E substantially as herein before described, and
as illustrated in Figs. 1, 2 & 3 of the drawings.
2nd. A dynamo electric machine having the poles of-the-field arranged alternately
in different planes and excited by a single coil and having a metal plate A2 arranged
substantially as hereinbefore described, and as illustrated in Figs. 4 & 5 of the
drawings.
3rd A-dynamo-electric--machine-having-the--poles-of-the--field--arranged--in
different planes-in-eombination-with-an-armature-constructed-and-arranged-sub-
stantially-as-described-so-that--one-part-of-the-armature-coincides with-the-pole
pieces-in-one-plane-of-the field, and-another-part of-the-armature coincides-with-the
pole-pieces-in-another-plane-of-the-field,-the-pole-pieces-of-the-field-being of such
length--as--to--ensure--any desired-number-of-the-wires-on-the-armature-being
simultaneously exposed to the direct-action-of-the-poles-substantially-as-hereinbefore
described.
ath 3rd. In a dynamo electric machine having the field pole pieces arranged in
different planes; an opening or gap or openings or gaps in a part or in parts of the
armature where no leakage can take place, the said opening or gap or openings or
gaps forming au increased resistance in the magnetic circuit substantially as here-
inbefore described.
4th. In a dynamɔ electric machine having the field pole pieces arranged in

page_text: different planes, gaps or openings in some portion of the field where no leakage can
take place the said gaps or openings forming an additional resistance in the magnetic
circuit substantially as hereinbefore described.
6th. A dynamo-electric-machine-having its ends closed and having ventilating
openings in-the-body of the field-magnet, the said openings being covered by and s
containing wire-gauze substantially as and-for-the purpose-hereinbefore-described.
Dated this 21st day of July 1896.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents