IMPROVEMENTS IN THE CONSTRUCTION OF DYNAMO-ELECTRIC MACHINES
Year: 1882

page_text: LETTERS PATENT to Charles Wilson Vincent of Holloway in the County of
Middlesex for an invention of "IMPROVEMENTS IN THE CONSTRUCTION OF
DYNAMO-ELECTRIC MACHINES" The result partly of a communication to him
by William Buller Fullerton Elphinstone Baron Elphinstone at present
residing in Canada and partly of invention and discovery made by him.
PROVISIONAL SPECIFICATION left by the said Charles Wilson Vincent at
the Office of the Commissioners of Patents on the 18th May 1882.
CHARLES WILSON VINCENT of Holloway in the County of Middlesex. "IMPROVE-
MENTS IN THE CONSTRUCTION OF DYNAMO-ELECTRIC MACHINES." [The result
partly of a communication to him by William Buller Fullerton Elphinstone Baron
Elphinstone at present residing in Canada and partly of invention and discovery
made by him.]
This invention relates firstly to a mode of facilitating the manufacture of the
coils of armatures constructed according to the invention for which I in conjunction
with Lord Elphinstone obtained Letters Patent bearing date January 27th 1879,
No 332.
Hitherto it has been customary to wind the coils in situ, such coils lapping over
the ends of the drum and preventing access to the interior in which a fixed field
magnet is situate.
The form of the coils which we employ is that of a broad link composed of one
or more wires, and it is now proposed to wind each coil on a "former," making it
of suitable length to fit the armature drum as before. In order however to allow
of the ends being bent over, heat, in the form of a current of electricity, is applied
to the coils to soften them, and while in this soft state the coil is moulded by
pressure on the drum to the form required.
As a further improvement it is proposed in some cases to increase the length of
the drum and to lay the coils upon the drum without bending over the ends.
In order to provide for a given diameter of drum taking the maximum number
of coils we have hitherto caused the coils to overlap and thereby cover the whole

page_text: periphery of the drum. It is still proposed to adhere to this arrangement but to
keep the sides of the coils at a uniform level, while the ends by overlapping form
irregular ridges. These ridges will however lie external of the plane occupied by
the field magnets and they may be covered by a hoop or belt which will serve to
retain the coils in position.
In some cases I propose to have two layers of coils thus disposed, and I thereby
obtain the advantage of causing two currents running in opposite directions to meet
at the same collecting brush.
In order to facilitate access to the interior of the drum it is proposed to form the
drum in sections, and to connect these sections together by screws and nuts or
otherwise. To admit of the separation of these sections the coils must be arranged
in groups upon each section and thus no disturbance of the coils will occur in
taking the armature drum to pieces.
The invention relates thirdly to the application of coils to disc armatures.
For this purpose the coils are arranged radially around the axis of the armature
in the form of a ring the coils being lapped over one another in the manner above
explained and clamped between a pair of discs of wood or other suitable material.
This armature is intended to rotate between two sets of field magnets with
opposing poles composed of bobbins clamped between fixed boards drilled with a
ring of holes to allow of the cores of the bobbins projecting through. The coils of
the armature may vary in form, that is to say they may be pear-shaped, or they
may take a circular, or other form as thought desirable.
In the specification of the patent above referred to, the machine was described
as fitted with a commutator and provided with six collecting brushes. For certain
purposes, however, it has been found necessary to connect these brushes together
in two groups. It is now proposed instead of connecting the six brushes together,
to use but one pair of brushes, and to connect the plates of the commutator in
groups of three, by means of moveable triangular metal plates, insulated the one
from the other. By this means we not only reduce the friction on the commutator,
but considerably diminish the "sparking" due to extra currents, and also loss of
current from frequent making and breaking contact.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Wilson Vincent in the Great Seal Patent Office on the
18th November 1882.
CHARLES WILSON VINCENT of Holloway in the County of Middlesex
"IMPROVE-
MENTS IN THE CONSTRUCTION OF DYNAMO-ELECTRIC MACHINES," Being the result
partly of a Communication to me by William Buller Fullerton Elphinstone Baron
Elphinstone at present residing in Canada and partly of invention and discovery
made by myself.
This Invention relates firstly, to a modo of facilitating the manufacture of the
coils of armatures constructed according to the Invention for which I in conjunction
with Lord Elphinstone obtained Letters Patent bearing date January twenty-
seventh One thousand eight hundred and seventy nine No. 332.
Hitherto it has been customary to wind the coils or hanks of the armature
in situ, which coils by reason of their lapping over the ends of the drum formed
an obstacle to the removal of the internal field magnets.
The form of the coils or hanks used in our machine is that of a broad link
composed of one or more wires and it is now proposed to wind each coil on a
"former" making it of suitable length to fit the armature drum as before.
"1
In Sheet I of the Drawings Fig: 1 shows a coil or hank of the form which we
employ Fig: 2 is a side view and Fig: 3 an edge view of the "former
on which
this hank is wound.-It consists of a base board a which is to be mounted on a
mandril, and of a moulding block b, which is made fast by screws and fly nuts c c
to the base board.
This moulding block is composed of three loose pieces (see Fig: 2) the middle
piece lying diagonally and being slightly chamfered inwards at its contact edges
to facilitate by its removal the withdrawal of the hank from the moulding block
when that block is detached from the base board.
"
The wire to be formed into the coil or hand is first coated with cotton yarn in
the usual way; it is then passed through a bath of insulating material such as
asphalte dissolved in liquid hydrocarbon, or of any approved insulating compound,
and while still wet from the bath the wire is slowly coiled by hand upon the
former," short lengths of tape having been first placed transversely around the
former to receive the wire.-When the requisite length of wire has been coiled
into the hank the hauk is bound by the tapes to keep the coils together and the
"former" is removed from the mandril and placed in a drying chamber to evaporate
the solvent therefrom.
"
#
"
When the insulating material has set or hardened the hank is removed from the
former," and it then presents the appearance of Fig: 1-In fitting it to the
armature drum it will however be necessary to bend over the ends of the hank in
order that they may be held fast by bands or clips to the drum ends. To facilitate
this bending over of the ends, heat in the form of a current of electricity is applied
to each hank to soften it, and while in this soft state the banks are moulded by
pressure on the drum to the form required as shewn at Fig: 4.
As a further improvement in drum armatures it is proposed to increase the
length of the drum and to lay the hanks upon the drum without bending over
the ends. In order to provide for a given diameter of drum taking the maximum
number of coils or hanks they have hitherto been caused to overlap each other and
thereby cover the whole periphery of the drum.-It is still proposed to adhere to
this arrangement, but to keep the sides of the banks at a uniform level while the
ends by overlapping form irregular ridges These ridges will however be external

page_text: of the plane occupied by the field magnets and they are covered by a hoop or belt
which will serve to retain the hanks in position :-
This is the arrangement shewn in the accompanying drawings which illustrate
the improved dynamo electric machine:-
In Sheet II Fig: 5 shews in side elevation the improved machine and Fig: G is
an elevation of the commutator end of the same.
In Sheet III Fig: 7 is a longitudinal sectional elevation and Fig: 8 is a
transverse vertical section of the machine.
In these Figures A A are standards bolted to the bed plate B and carrying a
fixed shaft C.
To this shaft are fitted radial plates of soft iron D D, constituting the stationary
internal magnets.
Mounted loosely upon the shaft C and surrounding the magnets D is an
armature drum E.
The heads of this drum consist of open discs formed with elongated hubs or
sleeves fitting onto journals on the shaft C.
The heads are connected to the barrel of the drum (which is made of some
diamagnetic material such as millboard) by screws inserted in its periphery or in
any other convenient manner.
Surrounding the drum are hanks of insulated wire e laid longitudinally thereof.-
The way of arranging these hanks and of bringing down the terminals of the
hanks is clearly shown in Fig: 7 Sheet III and Fig: 9 Sheet I, which latter Figure
shows the commutator end of the armature drum.
The armature drum is situate between the side frames F F which are bolted
to the bed plate B.
The use of these side frames is to carry the magnets G G which surround the
armature drum and constitute the outside field magnets.-These magnets Gare
composed of plates of soft iron, and are V-shaped in cross section, which mode of
construction is adopted to facilitate the winding-on of the insulated wire.
The magnets G aro set radially and concentrically around the armature drum,
and are secured to the side frames by transverse brass or gun-metal bolts G¹, which
extend from one side frame to the other.
H is the commutator keyed on a sleeve of the armature drum, and I is a band
pulley keyed on the other sleeve of the drum. Through this pulley rotary
motion is imparted to the armature drum for the purpose of setting the machine
in action.
K is an annular frame carried by and capable of rotation upon the fixed
shaft C. This frame carries the commutator brush holders, and may be fixed in
any required position by means of the screw chips k
The magnets D (see fig 8) are so coiled as to constitute them alternately north
and south poles as indicated by the letters N and S.
Similarly the magnets G are so arranged as to present opposing poles to the
magnets D, as is also indicated by the letters N S.-Both the internal and external
magnets are provided with broad pole-pieces for the purpose of presenting broad
magnetic fields to the coils or hanks of the rotating armature, and the ends of the
coils of these two sets of magnets are led to a tablet L to receive the exciting
current from the commutator brushes.
In the drawings Figures 8 and 9 shew that the armature drum is provided with
eighteen hanks of insulated wire-These hanks are composed each of two wires so
as to produce two distinct currents or the number of hanks may be doubled ench
hank being formed of a single wire--Thus the hanks will in either case present a
total of seventy two terminals which are permanently connected in pairs each pair
with a bar of the commutator H.
The construction of this commutator is best illustrated by the detached views
Figures 10 and 11 sheet I, which represent it on an enlarged scale,-Fig: 10
being an end view partly in section and Fig 11 a longitudinal section of the
commutator.

page_text: It consists of a brass cylinder h upon which is fitted a cylinder of vulcanite h¹
grooved longitudinally to receive a series of brass bars h², in this case thirty-six in
number, two for each double coil on the armature-The terminals of these coils
are brought down to their respective bars and secured thereto by clamping screws.
These bars are V-shaped in cross section and they are severally formed with a
bevilled recess at each end.
The brass cylinder h is provided at one end with a bevilled flange to receive one
of the recessed ends of the bars h2, but is insulated therefrom by means of a
vulcanite cone h³, an annular plate similarly bevilled to fit the opposite ends of
the bars h³ and insulated therefrom is secured to the other end of the cylinder h
by bolts h. By screwing up these bolts the bars h² will be drawn down into the
grooves in the vulcanite cylinder h¹ and securely held therein
I have stated that the hanks e on the armature drum E extend beyond the
plane of the field magnets to allow of their ends being held down on the periphery
of the drum.
This is clearly shewn in Figures 5 and 7 Sheet III.
The hanks being placed upon the drum as described, their ends are bent (without
the application of heat) to accommodate them to the overlapping of one hank over
the other, and to ensure their lying in a close and compact state. A binding cord
is then laid around the covered drum for a breadth somewhat exceeding the length
of the field magnets in order to secure the hanks in position-As a further security
cap rings e¹ are placed over the ends of the hanks and made fast by screws to the
armature drum heads.
In some cases it is proposed to have two layers of hanks disposed as just
described, and by connecting then to the commutator plates in the manner shewn
and explained by the consecutive numbers in Fig: 9, we obtain the advantage
of causing two currents running in opposite directions to meet at the same
collecting brush.
In order to facilitate access to the interior of the drum it is proposed to form the
drum in sections and to connect these sections together by screws and nuts or
otherwise. To admit of the separation of these sections the coils must be arranged
in groups upon each section, and thus no disturbance of the coils will occur in
taking the armature drum to pieces.
Fig 12 sheet IV shews in end elevation the armature drum constructed in
segments. The end plates are provided at their radial divisions with flanges which
receive screw bolts for connecting them together. The several segments of the
drum have their coils arranged as shewn in the end view. Thus the drum is
provided with three separate and detachable groups of hanks the removal of either
of which group from its place to give access to the interior of the drum will not
affect those which remain in place.
The invention further relates to the application of coils or hanks to disc
armatures
For this purpose the coils are arranged radially around the axis of the armature
in the form of a ring the coils being lapped over one another in the manner above
explained and clamped between a pair of discs of wood or other suitable material.----
This armature is intended to rotate between two sets of field magnets with opposing
poles composed of bobbins clamped between fixed boards drilled with a ring of
holes to allow of the cores of the bobbins projecting through
In sheet V fig: 13 is a front elevation of a dynamo electric machine constructed
with a disc armature according to this part of the Invention-Fig: 14 is an end
elevation and fig: 15 a longitudinal vertical section of the same.
In these figures A is the bed of the machine from which rise slabs of wood B B
for carrying the field magnets C C-These slabs are secured to the bed plate by
means of iron brackets and they are pierced at their centres for the passage through
them of the compound shaft D D' which carries the disc arinature E.
Fitted to the slabs B are bearings B' B' in which the armature shaft rotates. On
the end of the part D of this shaft the disc armature is mounted.

page_text: It consists of a central wooden disc e to the sides of which, discs e¹ e' are secured
by screws for the purpose of clamping between them a pair of larger discs e² e
composed of millboard or other suitable material
Between these discs e a series of hanks es e³ is arranged in the manner shewn in
fig: 16 which represents the armature detached from the machine and with one of
the enclosing discs removed
The hanks are set radially and they overlap the one the other in order to ensure
a rapid succession of hanks passing through the fields of force when rotary motion
is given to the armature.
The ends of the wires forming the hanks are led to the commutator F through
the part D' of the compound shaft, which part is composed preferably of brass, and
is made hollow for the passage of the wires to the commutator
This commutator which is carried by the armature shaft may be similar in
construction to that above described.
"
It will be understood that the hanks for this armature are to be wound on a
"former," as above explained and they may be made of single or of double wires
as thought most desirable.
The field magnets are composed of bobbins fitted with cores of soft iron which
form also tie-bolts for connecting the pairs of wooden slabs B B together.
The means for collecting the currents and distributing them to the fields and to
the outside circuits will be the same as that explained above in relation to the
drum armature machine.
In the Specification of the Patent above referred to the machine was described
as fitted with a commutator and provided with six collecting brushes. For certain
purposes however it has been found necessary to connect these brushes together in
two groups. It is now proposed instead of connecting the six brushes together to
use but one pair of brushes and to connect the bars, strips or plates of the com-
mutator in groups of three, by means of removable metal coupling plates insulated
the one from the other.
In sheet VI fig: 17 is an end view of the commutator with the coupling plates
applied thereto; fig 18 a side elevation and fig 19 a partial sectional elevation of
the same.
In these figures h² are the bars of the commutator H, coupled up as already
explained with the hanks of the armature. The exposed ends of these bars have
sockets formed in them to receive contact pins projecting from the inner face of a
series of coupling plates ho
These plates consist of thin pieces of sheet brass fitted upon the armature sleeve
but insulated therefrom, and from each other; they are packed closely together
and are set in front of the exposed end of the commutator.
To each of these plates ho three contact pins are fitted at equal distances from
each other, and at such a length of radius as to reach the sockets in the exposed
ends of the commutator bars.
The length of these contact pins will vary, for each plate: the pins of the outer-
most plate having to reach over all the coupling plates which lie between it and
the commutator.
It will now be understood that when these coupling plates are brought up into
position as shewn in the drawing, they will couple up the bars h² in groups of
three thus making virtually a series of twelve terminal plates for the armature
arranged as above described.
"
By this means not only is the friction on the commutator reduced, but the
sparking" due to extra currents is considerably diminished, as is also loss of
current from frequent making and breaking contact.
This construction of coupler it will be obvious is applicable to other forms of
commutator than that above described.
Having now explained the nature of the Invention of "Improvements in the
construction of dynamo-electric machines" and explained the manner of carrying

page_text: the same into effect, I wish it to be understood that under the above in part recited
Letters Patent I claim:
First Forming the banks of the armatures of dynamo electric machines by
winding them upon a rotating "former," and moulding the same by heat and
pressure, or by pressure alone, in the manner and for the purpose above setforth.
Secondly The construction of drum armature as described with reference to
Figures 5 and 7.
Thirdly Constructing armature drums in segments, and grouping the hanks to
correspond thereto, in the manner and for the purpose above described:
Fourthly The arrangement of disc armature machine as above described.
Lastly: The means above described for grouping the currents derived from
armature coils, and thereby minimising the "sparking" and the friction put upon
the commutator by the brushes or rubbers.
In witness whereof I the said Charles Wilson Vincent have hereunto set my
hand and seal the Seventeenth day of November in the year of our Lord
One thousand eight hundred and eighty two.