IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES
Year: 1883

page_text: LETTERS PATENT to Frederick John Cheesbrough of the Office for Patents,
15 Water Street Liverpool in the County of Lancaster Consulting Engineer
for an Invention of IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES
communicated to him from abroad by Edward R. Knowles of Brooklyn
in the County of Kings State of New York United States of America
PROVISIONAL SPECIFICATION left by the said Frederick John Cheesbrough
at the Office of the Commissioners of Patents on the 1st January 1883.
FREDERICK JOHN CHEESBROUGH, of the Office for Patents, 15 Water Street,
Liverpool, in the County of Lancaster, Consulting Engineer IMPROVEMENTS IN
DYNAMO ELECTRIC MACHINES [communicated to him from abroad by Edward
R. Knowles of Brooklyn in the County of Kings State of New York United States
of America]
This Invention consists, first of an improved armature, second of an improved
method of combining the armature with the magnet; third of an improved
commutator, and fourth of a combination of all the improvements in one
machine.
In writing this Specification it is assumed that the general principle of
dynamo electric machines is understood and therefore the Specification is confined
to a description of the machine as constructed and improved by the present
Inventor
According to this Invention the core of the armature consists of a series of iron
rings made in the form of a true circle and fitted together one outside of another
until the required thickness is obtained. These rings are fastened together by.
screws, or pins and are then cut from the outside and inside, so that the ends of
one section lap over the ends of its contiguous section, the two forming a lap joint,
which is secured by pins. This core may of course be made of one solid ring
and wound by hand as armature rings are usually wound but it is much more
convenient to make it as above set forth and wind it by machine, as hereinafter
described.

page_text: The core having been "made the next step is to wind it by machinery This is
accomplished by first making a set of cast iron bobbins. These bobbins are made
with a flange at each end and through them longitudinally is made a hole of the
form size and radius exactly equal to that of the core. They are then put in a
lathe upon a correspondingly shaped mandril and wound with the usual wire
drawn off of a reel, both ends of the coil being left free to connect with the
commutator as hereinafter described.
The necessary number of bobbins having been wound as aforesaid are then
slipped on the two sections of the core, the ends of which are then brought together
and connected as aforesaid. These bobbins are distributed upon the core equi-
distant apart, the intervening spaces being filled by U shaped clamps and insulating
rings that embrace the core on three sides and abutt against the inside face of the
wheel to which they are bolted by screws The bobbins and the clamps are thus
made to embrace the entire surface of the core, excepting the points of contact
between the ends of the clamps and the inside face of the wheel, covering all the
pins that unite the sections of the core and keeping them from working loose.
The wheel that carries the armature is made of brass, or other non magnetic
material and bolted to a shaft carried in suitable bearings
Having completed the construction of the armature, the construction of the
magnets is proceeded with. There are six of them, three above and three below.
This number may of course be increased, or diminished as circumstances may
require. One end of each of these magnets is bolted to a frame, which in its turn
is firmly bolted to a solid foundation, the magnets projecting from the frame
towards the wheel. The ends of the magnets are bolted to cheek pieces. These
cheek pieces are grooved out to form a section like the letter U and are made to
embrace the armature, or ring on three sides, the ring being adjusted on the wheel
to travel in the groove of the cheek pieces. The rear ends of the magnets are of
course, firmly held by the frame and the cheek piece of the lower magnet is firmly
bolted to the bed plate. But to steady and hold firm the cheek piece of the upper
magnets there is introduced a non magnetic ring bolted to the upper and lower
cheek pieces the shaft passing through the ring.
Having constructed and combined the armature and magnet as described, the
commutator is made as follows: It consists of a series of sectors united at their
outer and inner ends to form a disc rotating upon a vertical plane. The outer ends
are united by means of two rings of insulating material one on each side of the
disc secured by screws passing from ring to ring through the sectors, each of which
are of course duly insulated The inner ends of the sectors are secured by sector
flanges bolted to an insulating ring, which in its turn is bushed with a metal ring
upon which the commutator is secured to the shaft by a set screw.
The brush holders consist of two U shaped brackets that embrace the edges of
the disc upon opposite sides In each end of one bracket a stud is placed raising
up to the upper periphery of the disc, and in each end of the other bracket, there is
a stud hanging pendant to the lower periphery of the disc. In each of these studs
a slit is cut or formed to receive the brushes of which there are four, two on each
side of the disc.
The brackets are secured to a cross head, bolted to the frame of the machine, the
bracket being insulated from the cross head and the shaft passing through the
centre of it. The coils of the armatures are wound in the same direction and are
connected, as in the Paccinotti ring, the outside of the one to the inside of the next
and so on forming a continuous closed coil of wire around the ring.
The connections are made as follows: on the shaft close to the hub of the wheel
is placed a ring of insulating material. On the circumference of this ring are
fastened pieces of metal by screws, or pins. In each of these pieces are set screws.
The outside end and the inside end of the two adjacent coils are fastened to pieces
by means of these screws, thus making a continuous connection of all the coil.
A wire leading to the commutator is fastened to each of the pieces by the set
screws, thus making a connection at the junction of each of the coils with the

page_text: commutator as in the Paccinotti machine. These wires are carried along the shaft
of the machine from which they are insulated to which they are securely fastened
by bands.
The magnets of the dynamo are connected seriatim, so that the upper three are
of one polarity and the lower three of opposite polarity. The ends of the magnet
coils are brought to a binding post. The ends of the commutator are brought to
another binding post. By this arrangement the dynamo may be made to charge
itself, or the magnets may be charged by an auxiliary machine and the terminals
of the armature connected directly to the external circuit.
The principal points of advantage resulting from this Invention are as follows
First By this arrangement of the magnet and armature, three sides of the wire
of the armature are embraced within the field of the magnet, by which a much
better magnetic effect is obtained than there can be by bringing the magnet to act
on only one, or two sides of the armature and
Second By constructing the armature as herein described it can be effectually
wound by machinery, instead of the slow laborious and expensive process of
hand winding and can be made perfectly true to rotate closely in the field of the
magnet.
Third By constructing the commutator as herein described, both surfaces of the
metal are utilized for brush contact, twice as much surface is obtained and the
sparking and heating greatly reduced.
Fourth By bringing all these novel features together in one machine, a dynamo
machine is produced of much greater efficiency.
Fifth By connecting the armature to the face of the wheel moveable on the
shaft and the circuit wires to the shaft by means of screws, the armaturo can be
withdrawn from the field of the magnets by merely loosing the screws or other
fastening that secures the wheel to the shaft and disconnecting the circuit wires
from the contact pieces as described

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Frederick John Cheesbrough in the Great Seal Patent Office on
the 29th June 1883.
FREDERICK JOHN CHEESBROUGH, of the Office for Patents, 15, Water Street,
Liverpool, in the County of Lancaster, Consulting Engineer "IMPROVEMENTS IN
DYNAMO ELECTRIC MACHINES "-A Communication to me from abroad by Edward
R: Knowles, of Brooklyn, in the County of Kings, State of New York, United
States of America
The following is a description of the Invention in such full, clear exact and
concise torms as will enable anyono skilled in the art to which it is most nearly
connected to make and use the same, reference being had to the accompanying
Drawings making part of this Specification, and to the letters and figures of
reference marked thereon.
By Figure 1 of said Drawing is shown a side elevation of a completed machine
built upon the plan of this Invention. Figure 2 is a longitudinal vertical section
through armature and cheek pieces of the magnets Figure 3 is an end view of
the machine looking against the end of the check pieces and tho side of the wheel
that carries the armature. Figure 4 is an end view of the machine looking against
the ends of the magnets and the frames that carry them. Figure 5 is a plan of
the core of the armature. Figure 6 is a front view of the completed armature.
Figure 7 is a back view of the same Figure 8 is a top view and Figure 9 is a side
elevation of the commutator both upon an enlarged scale. Figures 12. 13. 14. 15
and 16 are parts in detail to be hereinafter referred to.
Like parts are represented by like letters in the different figures.
This Invention consists first of an improved armature, second of an improved
method of combining the armature with the magnet; third of an improved
commutator, and fourth of a combination of all of the improvements in one
machine.
In writing this Specification it is assumed that the general principle of dynamo
electric machines is understood and therefore the description is confined to the
machine as constructed according to this Invention, the points of novelty being
designated in the claims concluding this Specification.
To commence with a description of the core of the armature illustrated in the
Drawing by Figure 5. It consists of a series of iron rings made in the form of a
true circle and fitted together one outside of the other, until the required thickness
is obtained. These rings aro fastened together by screws, or pins O and are then
cut from the outside and inside upon the lines m m so that the ends of one section
lap over the ends of its contiguous section-the two forming a lap joint secured by
pins n. This core may of course be made of one solid ring and wound by hand as
armature rings are usually wound, but it is much more convenient to make it as
above set forth and wind it by machine as hereinafter described.
The core having been made the next step is to wind it by machinery This is
accomplished by first making a set of cast iron bobbins shown in the Drawing by
Figure 15. These bobbins are made with a flange V at each end and through
them longitudinally is made a hole of the form size and radius exactly equal to
that of the core. They are then put in a lathe upon a correspondingly shaped
inandril and wound with the usual wire drawn off of a reel-both ends of the coil
being left free to connect with the commutator as hereinafter described.
The necessary number of bobbins having been wound as aforesaid are then
slipped on the two sections of the core, the ends of which are then brought

page_text: together and connected as aforesaid. These bobbins as wound and placed upon
the core are shown by H Figures 6 and 7. They are distributed upon the core
equidistant apart-the intervening spaces being filled up by U shaped clamps G
and insulating rings R' that embrace the core on the three sides and abut against
the inside face of the wheel B to which they are bolted by screws The bobbins
and the clamps are thus made to embrace the entire surface of the core excepting
the points of contact between the ends of the clamps and the inside face of the
wheel B covering all the pins that unite the sections of the core and keeping them
from working lonse.
The wheel B that carries the armature is made of brass, or other non magnetic
material and bolted to a shaft C carried in suitable bearings D and D' as shown by
Figure 1.
Having completed the construction of the armature the construction of the
magnets is proceeded with. These are illustrated in the Drawings by L. There
are six of them; three above and three below; as is clearly illustrated by Figure 4.
Their number may of course be increased, or dimished [sic] as circumstances may
require. One end of each of these magnets is bolted at h to the frame M, which
in its turn is firmly bolted to a solid foundation the magnets projecting from the
frame M towards the wheel B. The cores of the magnets are shown by Land to
their ends are bolted the cheek pieces A by bolts V. These cheek pieces are
grooved out to form a section like the letter U and are made to embrace the
armature, or ring on three sides as shown by Figure 2, the ring being adjusted on
the wheel B to travel in the groove of the cheek pieces. The rear ends of the
magnets are of course firmly held by the frane 31 and the cheek piece of the lower
magnet is firmly bolted to the bed plate at g. g. But to steady and hold firm tho
cherk piece of the upper magnets there is introduced a non magnetic ring F and
bolted to the upper and lower cheek pieces, the shaft C passing through the ring
in the manner shown. A front view of the cheek piece is shown by Figure 14, the
magnets Lappearing behind it in dotted lines. This Figure and also Figure 4 very
fully show the application of the ring F to the check pieces.
Having constructed and combined the armature and magnet as described the
commutator is made as follows, a side view and top view of it being shown upon
an enlarged scale by Figures 8 and 9. It consists of a series of sectors O united
at thoir outer and inner ends to form a disc rotating upon a vertical plane. The.
outer ends are united by means of two rings of insulating material one on each
side of the disc secured by screws. D passing from ring to ring through the sectors,
each of which are of course duly insulated. The inner ends of the sectors are
secured by sector flanges G bolted to insulating ring F which in its turn is bushed
with a metallic ring E upon which the commutator is secured to the shaft C by a
set screw M
The brush holders consist of two U shaped brackets K K' that embrace the
edges of the disc upon opposite sides. In each end of the bracket K¹ a stud I is placed
raising up to the upper periphery of the disc and in each end of the bracket K
there is a stud I hanging pendant to the lower periphery of the disc. In each of
these studs a slit is cut, or formed to receive the brushes P of which there are four,
two on each side of the disc as shown in Figure 8.
The brackets are secured to a cross head Q bolted to the frame of the machine,
the bracket being insulated from the cross head by pieces V" V" and the shaft
passing through the centre of it in the manner shown. The coils of the armatures
are wound in the same direction and are connected as in the Paccinotti ring, the
outside of the one to the inside of the next and so on forming a continuous closed
coil of wire around the ring.
The connections are made as follows on the shaft C close to the hub of the
wheel B is placed a ring of insulating material W Figures 2. 6. 7 12 and 13. On
the circumference of this ring are fastened pieces of metal rp by screws, or pins t.
In each of these pieces are set scrows S S. The outside end and the inside end of
the two adjacent coils are fastened to pieces r by means of these screws, thus

page_text: making a continuous connection of all the coil H. A wire W₁ leading to the
commutator is fastened to each of the pieces r by the set screws S¹, thus making a
connection at the junction of each of the coils H with the cominutator as in the
Paccinotti machine. These wires W Ware carried along the shaft of the machine
from which they are insulated to which they are securely fastened by bands R R R.
The magnets of the dynamo are connected seriatim, so that the upper three are
of one polarity and the lower three of opposite polarity. The ends Y Y' are
brought to the binding posts o and d. The ends X and X' of the commutator are
brought to the binding posts a b. By this arrangement the dynamo may be made
to charge itself as shown by the connections in Figure 1, or the magnets may be
charged by an auxiliary machine and the terminals of the armature connected
directly to the external circuit.
The principal points of advantage resulting from this Invention are
First By this arrangement of the magnet and armature, three sides of the wire
of the armature are embraced within the field of the magnet, by which a much
better magnetic effect is obtained than there can be by bringing the magnet to act
on only one, or two sides of the armature and
Second By constructing the armature as described it can be effectually wound
by machinery instead of the slow laborious and expensive process of hand winding,
and can be made perfectly true to rotate closely in the field of the magnet.
Third By constructing the commutator as described both surfaces of the metal
are utilized for brush contact, twice as much surface is obtained and the sparking
and heating greatly reduced.
Fourth By bringing all these novel features together in one machine a dynamo
machine is produced of much greater efficiency than any of which I have any
knowledge.
Fifth By connecting the armature to the face of the wheel moveable on the
shaft and the circuit wires to the shaft by means of screws the armature can
be withdrawn from the field of the magnets by merely loosing the screws or other
fastening that secures the wheel to the shaft and disconnecting the circuit wires
from the contact pieces as described.
What I claim as the Invention communicated to me by my Foreign corre-
spondent is
First In a dynamo electric machine an armature ring having its core composed
of two, or more concentric rings placed one inside of the other and united
substantially as described.
Second In a dynamo electric machine an armature ring consisting of the
following elements, namely a core composed of two, or more para magnetic rings
placed one inside of the other, said rings being divided transversley as described, a
series of para magnetic bobbins duly wound and placed on said core and a series of
intervening clamps G placed on the core between the bobbins substantially as
described.
Third In a dynamo electric machine the combination of cheek pieces A with the
cores L' of the magnets; said cheek pieces being made separate and bolted to the
ends of the magnet cores forming their poles and being grooved out to receive
and embrace the armature ring substantially as described.
Fourth In a dynamo electric machine a commutator having two magnetic
rubbing surfaces set transverse its rotating axis and exposing both of said rubbing
surfaces to the collecting brushes
Fifth In a dynamo electric machine a commutator having two magnetic rubbing
surfaces, each of which is combined with a collecting brush.
Sixth The combination of clamps G with the coils and core of the armature for
the purpose of filling the space between the coils and securing the ring to the
wheel B that carries the ring.
Seventh The combination of a magnet A an armature ring in the field of said
magnet and a wheel B made moveable on the driving shaft C, the several parts
coacting to allow the ring to bo, removed from the field of the magnets by loosing

page_text: the fastening of the wheel to the shaft and the connecting circuit wires W and W
substantially as described.
Eighth The combination of the insulating ring W and contact pieces r with the
shaft C by which the circuit wires are connected and disconnected.
In Witness whereof, I, the said Frederick John Cheesbrough, have hereunto
set my hand and seal this twenty seventh day of June in the year of
our Lord one thousand eight hundred and eighty three.
PARADYAT
TADA CHEESDRONCH