IMPROVEMENTS IN DYNAMO-ELECTRIC MACHINES
Year: 1884

page_text: I EDWARD JONES of Westhill Terrace, Chapel Allerton, Leeds in the County of
York, Mechanical Engineer do hereby declare the nature of my invention for
"IMPROVEMENTS IN DYNAMO-ELECTRIC MACHINES," to be as follows:-
This invention relates to an improved electric generator, the objects in view
being to reduce the cost of construction and increase the efficiency of the machine.
This improved electric machine has only a single shaft bearing, the driving pulley
being keyed to one end of the shaft, and the armature and commutator to the
other end thereof. The field magnets are formed with pole pieces at one end only,
and the armature rotates between one or more pairs of these pole pieces, the shanks
or cores of the field magnets being arranged parallel to the armature shaft.
One end plate or standard serves to carry the single bearing for the armature
spindle and the shanks or cores of the field magnets, and by this arrangement free
access to the armature end of the machine can be had.
The segmental pole pieces of the field magnets are rigidly connected by a ring or
frame of diamagnetic material or metal such as brass, to prevent vibration at that
end, and this ring or frame serves as a guide or race for the brush holder and
rocker, the construction of which will be more fully indicated hereafter.
The single bearing for the armature spindle is preferably cast in one with the
end plate or standard of the machine to which the field magnets are bolted, and is
made hollow and slightly taper for strength and lightness.
It is accurately bored at its inner and outer ends to receive the bushing
(preferably of gun metal) for the spindle, and this bushing, which may be cast,
only requires turning at its extremities where it fits into the cast metal bearing or
support.
The bushing is of course accurately bored to receive the spindle.
This construction is very simple and facilitates the accurate fitting up of the
machine. The armature of my improved machine is constructed on the lines
indicated in the specification of my Patent dated 24th July 1883, N° 3633, but
I have introduced several improvements. therein.

page_text: To prevent the creation of currents in and around the pole pieces of the
armature, and to facilitate the circulation of air, I now arrange or group the pole
pieces in pairs around the hub, separating their inner and outer ends by spacing
blocks of wood or equivalent non conducting material, and securing them together
in that position by bolts or clips also of non conducting material. The pole pieces
are of U shape having their outer ends left open instead of being closed by filling
pieces, as described in the prior specification above referred to, and the core is
composed of a thick coil of iron wire, or iron in any other well divided form
wound with cotton or other fibrous material and varnished, or varnished only.
The hub of the armature is of taper form as before, but it is built up of segmental
blocks of wood having the end of the grain facing outwards to prevent alteration
in diameter due to expansion or contraction, and these blocks are held in place by
brass side plates and screws.
The hub thus constructed is keyed fast on the spinille; the pairs of pole plates
are disposed radially around the hub, and serve to force outward the iron wire
core and hold it concentric with the spindle. The pole pieces are forced on to
the taper hub, and held thereon by washers or collars which are forced against
them by uuts threaded on the spindle, as described in the above mentioned
specification the said washers or collars being insulated from the metal of the
armature.
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The fan shaped sections into which the core is thus divided by the pairs of pole
pieces, are wound with the required number of coils or bobbins of insulated copper
wire or tape. I preferably divide the armature into 12 sections each having
6 bobbins of wire wound thereon. The means for shifting the spindle endwise, and
adjusting the armature to its field, remain practically the same as described in my
specification above referred to.
The commutator, of any convenient construction, is keyed on the spindle close
against the armature and as there is no bearing at all needed for the spindle on
the commutator side of the armature, and no field magnet shanks or cores to
interfere, the connections may be made direct and short, and are always easily
accessible. There is also no necessity for drilling the spindle for the passage of the
conducting wires to the commutator, and the spindle therefore remains unweakened
at this part.
The brushes I make of a number of straight copper wires bound together, or
(and preferably) of flat strips of copper set edgewise side by side, and arranged to
present their end edges to the commutator plates; and I cause these brushes to be
fed forwards by a light spring or springs or their equivalent which tends to push
the brushes lengthwise through a suitably formed guide case or sheath against the
periphery of the commutator.
The angle at which the brushes meet the commutator may vary within
considerable limits, or the brushes may even be truly radial to the commutator,
the object in view being to maintain the rubbing area constant, whereas in
tangentially arranged brushes, as commonly used, the area of contact tends to
rapidly increase and to impair the efficiency of the machine. The guides or cases
through or against which the brushes of wire or copper strips pass, or are fed
forwards, and which also carry the spring or equivalent devices for feeding them
towards or against the commutator, are mounted on a ring of metal provided with
a bandle for rotating it, and varying the lead of the brushes. This brush rocking
ring is mounted to slide against the stiffening plate or frame rigidly uniting the
pole pieces of the field magnets, and is retained in place by a covering plate of card
or leather board, vulcanite, or other suitable material secured to the stiffening plate
or frame by screws.
This covering plate conceals and protects from injury the connections between
the armature and commutator. The lower pole piece or pole pieces rest on blocks
of wood of other suitable material,

page_text: This improved machine is compact and light, owing to the simplicity of the
construction and arrangement of the several parts. The commutator and armature
connections are greatly simplified and easy of access, while the armature is light,
rigid, easily adjustable, free from disturbing currents, and not liable to heat.
I may use 2, 4, 6 or more field magnets, but I have obtained excellent results
from two magnets, each with a deeply channelled semi-circular pole piece at one
end, and shanks or cores arranged horizontally and parallel to the shaft of the
armature, which shaft has one long bearing only carried by the end plate of the
machine to which the field magnets are bolted.
This machine may be used with but slight alteration as an electric motor.

page_text: "
I EDWARD JONES of Westhill Terrace, Chapel Allerton, Leeds in the County of
York Mechanical Engineer do hereby declare the nature of my invention for.
"IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES 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 an improved electric generator the objects in view
being to reduce the cost of construction and increase the efficiency of the machine.
This improved electric machine has only a single shaft bearing, the driving pulley
Leing keyed to one end of the shaft, and the armature and commutator being
mounted closely together on the other end thereof. The field magnets are formed
with deeply channelled role pieces from which the shanks or cores extend at one
side only, and the armature rotates between or within one or more pairs of these
pole pieces, the said shanks or cores being separately wound, and arranged parallel
to the armature shaft.
The invention also relates to various improvements in the details of construction
and combinations of parts which are hereinafter fully described and claimed.
The details of construction and general arrangement of parts in this improved
electric generator will be understood on reference to the accompanying drawing in
which Fig 1 is an elevation of the machine as seen from the end at which the
commutator and armature are situate, Fig 2 is a central longitudinal section of
the machine Fig 3 is a front view of the armature with only one coil in place, tho
better to illustrate the manner in which the armature is constructed and mounted
on its spindle; and Figures 4, 5 and 6 are detail views, of about one-half the
actual size, of the brush-rocker and brushes.
In these Figures the same letters of reference indicate like or corresponding
parts.
The main frame of the machine consists of a single end plate or standard, A,
which carries the single long bearing B for the spindle C of the armature D, and
also the cores or shanks ee of the field magnets E E.
For convenience in fitting, these cores or shanks ce are attached to the frame or
standard A by screw bolts, and the segmental pole pieces el e¹ of the field magnets
are rigidly connected by a ring or light frame F, of diamagnetic material or metal,
such as brass, to prevent any vibration at that end of the machine. A block G of
wood or other diamagnetic material is bolted to the pole piece e¹ of the lower
magnet or magnets and serves as a foot or support for the said magnet or magnets,
and (in case the machine is fixed on an iron bed plate) this block G insulates the
pole piece or pieces or holds them at a distance from the said bed plate.
The ring or frame F, besides preventing the vibration of the field magnets E'E
serves also as a guide or race for the brush rocker H.
The mode of mounting the brushes with respect to the commutator and the
construction, and arrangement of the brush rocker and brushes will be fully
explained hereafter,

page_text: I is the commutator fast on the shaft C and arranged in close proximity to the
armature D, and J is the driving pulley fast on the other end of the shaft C.
The single long bearing B for the armature spindle is preferably cast in one
with the end plate or standard of the machine to which the field magnets are
bolted, and is made hollow and slightly taper for strength and lightness.
As the bearing B is hollow or chambered to within a short distance from each
end it is only necessary to accurately bore it for a small portion at its inner and
outer ends to receive the bush b for the spindle, and this bush, which may be of
any usual and suitable material and may be cast, only requires turning at its
extremities or parts where it is fitted closely into or against the cast metal bearing
or support B.
The bush B. is preferably formed with a reduced external diameter between its
turned extremities, and is of course accurately bored to receive the spindle C.
This construction is very simple and facilitates the accurate fitting together of
the machine.
Such being the general construction and arrangement of the frame-work and
fiel magnets, I will now proceed to describe the way in which the armature of my
improved machine is constructed and mounted.
The armature of my improved machine follows the lines indicated in the
Specification of my Patent dated 24th July 1883, N° 3,633, but I have introduced
several improvements therein.
The pole pieces d d of the armature D I now arrange or group in pairs around
the hub D', separating the inner and outer ends of each pair of pole pieces by
spacing blocks dd of wood, or equivalent nonconducting material, and securing
them together in that position by bolts or clips (seen in Fig 2) also of non-
conducting material; by which construction and arrangement I. prevent the
creation of induced currents in and around the pole pieces of the armature, and
facilitate the circulation of air. The pole pieces d d are of U shape having their
outer ends left open instead of being closed by filling pieces in the manner
described in the Specification of my Patent above referred to, and may be
conveniently formed by stamping out of soft iron plate.
The core D' is composed of a thick coil of soft iron wire wound on a former, or
of iron in any other well divided form wound with cotton or other fibrous material
and varnished; or varnished only without being wound with cotton. The hub D'
of the armature is of slightly taper form, and made of a non-conducting material.
It is preferably built up of segmental blocks of wood having the end of the grain
facing outwards or radiating from the centre, to prevent alteration in diameter due
to expansion or contraction; and these blocks of wood, when such are used, are
bound together by brass side plates and screws.
The hub thus constructed of insulating material is keyed fast on the spindle C
the pole plates d d, connected in pairs as above described, are disposed radially
around the hub and serve to force outward the iron core D' and hold it concentric
with the spindle. The inner ends of the pole pieces are cut rather obliquely so as
to fit onto the slightly taper hub D', and are held thereon by washers or collars D³
which are forced against them by nuts threaded on the spindle C, as will be well
understood; the said washers or collars D³ being insulated from the metal of the
armature by washers or rings of insulating material d², as shewn in Fig 2.
The fan-shaped sections into which the core D is divided by the radially
arranged pairs of pole pieces & d, are wound with the required number of coils or
bobbins of insulated copper wire or tape, in such a manner as to fill each of the
said sections or spaces; I preferably divide the armature into 12 sections each
having 6 Lobbins of wire wound thereon.
>
By means of suitable adjusting screws and nuts the bush b, and with it the
spindle C can be shifted endwise, and the armature be thereby adjusted to its
field; but the means for effecting this adjustment form no part of my present
Invention. Any liability to end wise movement of the shaft C may be prevented
by means of nuts C¹ on the pulley end of the shaft, which nuts serve also to take

page_text: up any wear on the collars of the shaft. These adjusting nuts could also be
arranged in immediate proximity to the flange b¹ of the bush b, if desired...
The commutator I, of any convenient construction is keyed on the spindle C close
against the armature D, and as there is no bearing at all needed for the spindle on
the commutator side of the armature, and no field magnet shanks or cores project
at that side to interfere with the connections, the said connections may be made
direct and short and are always easily accessible. No necessity moreover exists for
drilling the spindle for the passage of the conducting wires from the armature to the
commutator, and the spindle therefore remains unweakened at this part.
I would here remark that I make no claim to any improvement in the con-
struction of the commutator itself.
I will now explain the method of mounting the brushes or collectors in my
improved single bearing dynamo machine.
The brushes H¹ I make of a number of straight copper wires bound together to
form a broad flat surface (see Fig 5), or of flat strips of copper set edgewise side by
side (see Fig 6) and arranged to present their ends or end edges to the commutator
plates, and I cause these brushes H¹ to be fed forwards by a light spring or springs h.
or their equivalent, which tends to push the brushes lengthwise through a suitably
formed guide case or sheath ' against the periphery of the commutator I.
The angle at which the brushes H¹ meet the commutator may vary within
considerable limits, or the brushes may even be set truly radial to the commutator
as shewn in full lines in Figs. 1 and 4, the object in view being to maintain the
rubbing area constant, whereas in tangentially. arranged brushes, such as are
commonly used, the area of contact tends to rapidly increase and to impair the
efficiency of the machine.-I preferably mount the brushes with respect to the
commutator in the position shewn in dotted lines in Fig: 4.
The guides or cases through or against which the brushes of wire or copper
strips pass or are fed forwards, and which also carry the spring or equivalent
devices h. for feeding them towards or against the commutator, are mounted on a
ring of metal H provided with a handle X, see Figures 1 and 2, for rotating or
rocking it and thereby varying the lead of the brushes.-This handle X also serves
as a clamping screw for securing the brush rocker in the desired position. This
brush rocker H is mounted to slide as in a bearing, against the stiffening plate or
frame F which rigidly unites the pole pieces of the field magnets E E, and the
ring H is retained in place by a covering plate K of card- or leather-board, vulcanite,
or other suitable material secured to the stiffening plate or frame by screws.
annular covering plate K conceals the connections between the armature and
commutator and protects them from injury. The brush guides or cases h¹ may be
moveable and adjustable with respect to the ring of metal H on which they are
mounted, to facilitate the setting of the brushes at the desired angle.
This
This improved machine is compact and light, and owing to the simplicity of the
construction and arrangement of the several parts, can be readily fitted together or
dismantled. The commutator and armature connections are greatly simplified and
so situate as to be easy of access; while the armature is light, rigid, easily adjustable,
free from disturbing currents, and not liable to heat.
I may use 2. 4. 6 or more field magnets, but I have obtained excellent results
from two magnets each with a deeply channelled pole piece at one end, and having
their separately wound shanks or cores arranged parallel to the shaft of the armature
which shaft is supported by one long bearing only, carried by the end plate or frame
of the machine to which the field magnets are bolted.
In this dynamo machine the armature coils are arranged transversely of the plane
of rotation and are surrounded preferably on three sides by the pole pieces of the
field magnets, as in the machine described in the Specification of my Patent above
referred to.
The cores of these field magnets are each separately wound, and each can be
readily attached or detached when required.
This machine may be used with but slight alteration as an electric motor.

page_text: 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
1. The arrangement of single bearing electric machine above described with
reference to Figures 1 and 2 of the Drawing, whereby an economy in construction
is effected, and easy access to the armature and commutator connections is secured.
2. In a dynamo electric machine the combination with a single standard or end
plate carrying a single long bearing, and an armature and commutator mounted closely
together on one end of a spindle adjustable lengthwise within the said bearing, of
one or more pairs of separately wound electro.magnets having their cores arranged
parallel to the armature spindle and terminating in deeply channelled pole pieces
within and between which pole pieces the armature coils rotate, substantially as
and for the purpose set forth.
3. An armature for dynamo electric machines consisting of a soft iron core
supported on U-shaped iron pole pieces arranged radially, in pairs, around a bub of
non-conducting material, the pole pieces in each pair being separated the one from
the other by spacing blocks of insulating material, and the several pairs of pole pieces
being secured on the hub and dividing the core into fan-shaped sections for the
reception of the coils of conducting wire, substantially as described with reference
to the drawing and for the purpose set forth.
4. In a single bearing dynamo machine the combination with the armature D,
field magnets E E, commutator I, and the brush holder and rocker H, of the dia-
magnetic ring or frame F forming a rigid connection between the pole pieces of the
said field magnets, and also a bearing or guide for the brush rocker; and the covering
plate or ring K for retaining the said brush rocker in place and serving to conceal
and protect the connections between the armature and commutator, substantially
as described with reference to the drawing.
5. In a dynamo electric machine, mounting the brushes or collectors in the manner
described with references to Figures 1. 2 and 4 of the drawing, whereby the contact
surface or rubbing area of the brushes on or against the commutator plates is main-
tained constant, and facilities are afforded for varying the lead of the brushes as
set forth.
6. In a dynamo electric machine the combination with the commutator I, of the
brush rocker H, brushes H¹, guide cases or sheaths h¹, and springs h. or their
equivalent, substantially as described; for the purpose of imparting a forward feed
to the brushes in a radial or nearly radial direction with respect to the commutator
and thereby maintaining constant their rubbing area, as set forth.