IMPROVEMENTS IN DYNAMO-ELECTRIO MACHINES
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
We WILLIAM HARDING SCOTT of 36 Park Street in the Town and County of the
Town of Nottingham, Electrician and EDUARD ALEXANDRE PARIS of 1 Warbeck
Road, Shepherd's Bush in the County of Middlesex, Electrician do hereby declaro
the nature of the said Invention for "IMPROVEMENTS IN DYNAMO-ELECTRIO
MACHINES," to be as follows that is to say :-
This Invention has for its object the construction and arrangement of dynamo-
electric machines or of parts thereof in an improved and convenient manner.
In carrying out the Invention there are four, or there may be any even number
more than two magnets and the armature is placed to rotate in the space between
the poles of these magnets and an iron core. The armature is in the form of a
hollow cylinder or drum having its circumference made of paper or other suitable
material surrounding the iron core which is carried on a fixed central spindle. At
the ends of the drum the paper or other material is connected to an annular piece
or ring of insulating material and this ring is recessed on its inner side to receive
part of a flat brass ring, and this brass ring is fixed in a recess formed to receive
the other part of it in a boss formed on a tubular piece through which the central
fixed spindle passes. By this convenient arrangement the tubular piece and its
boss which forms the end of the drum at either end may be removed to give access
to the iron core or interior when requisite the improved method of winding the
wire on the drum enabling this operation to be done without disturbing the wire.
The armature is driven by means of the tubular piece and the central fixed spindle
is formed hollow cither through its whole length or a portion thereof so that a
tube or pipe may be passed through the hollow spindle and through the iron core
into a hollow or oil-well formed in the iron core. The oil used in oiling the
tubular pieces will find its way into this hollow or oil-well and can be withdrawn
therefrom by the tube or pipe when required. The wire of the armature is wound
upon the drum in the following special manner. The periphery of the drum is
divided longitudinally into a number of equal parts and on commencing to wind
the wire is taken from the middle of one of the equal parts and the single wire is
taken from that part to a point opposite so as to form the chord of an arc of the
circle of the drum. This point is one end of an equal part thence the wire is taken
and wound longitudinally along the drum across its other end and back along
another equal and parallel part of the circumference of the drum thus making the

page_text: single wire and the rows of wound wire to form as it were approximately two
sides of a square looking at the drum end. The wire is thus wound longitudinally
on the drum over the single wire until one half of the equal part is taken up and
then the wire is passed to another equal part opposite so that looking at the end
of the drum the single line of wire and the suceeding rows of wound wire form
approximately the two sides of an imaginary square. After winding the wire as
in the first case until half of an equal space is covered the single wire is again
passed to another point in the circumference and the process repeated until the
whole circumference of the drum is covered with wire. Each single wire crossing
the end of the drum is connected to the commutator. Any number of layers of
wire may be wound over the first one and they may be connected up either in
series or in parallel. By this improved method of winding and by using four
brushes on the commutator they can be made to bear on the commutator at such
places that only those coils which are in the magnetic field are in circuit whilst
those which are not in the magnetic field are short circuited. Thus the effective
resistance of the arinature is reduced and the efficiency of the machine is necessarily
increased.
The fixed iron core may in some cases be wound with wire and there may be
substituted for the fixed iron core a core made of thin iron plates insulated and
revolving with the armature.

page_text: We, WILLIAM HARDING SCOTT of 36 Park Street in the Town and County of
the Town of Nottingham, Electrician and EDUARD ALEXANDRE PARIS, of
1 Warbeck Road, Shepherd's Bush in the County of Middlesex, Electrician, do
hereby declare the nature of our said 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 that is
to say:-
Our said Invention has for its object the construction and arrangement of
dynamo electric machines or of parts thereof in an improved and convenient
manner.
In carrying out our said Invention there are four (or there may be any even
number more than two) magnets and the armature is placed to rotate in the space
between the poles of these magnets and an iron core or its equivalent. The
armature is preferably in the form of a hollow cylinder or drum having its
circumference made of paper or other suitable material surrounding the iron core
which core is carried on a fixed central spindle. At the ends of the drum the
paper or other material is connected to an annular piece or ring of insulating
material and each of these rings is recessed on its inner side to receive part of a
fat metal ring and these metal rings are fixed to bosses on the ends of tubular
pieces through which the fixed shaft passes. By this convenient arrangement the
tubular piece and its boss which forms the end of the drum at either end may be
removed to give access to the iron core or interior when requisite, the improved
method of winding the wire on the drum hereinafter described enabling this
operation to be done without disturbing the wire. The armature is driven by a
pulley fixed on one of the tubular pieces and the fixed shaft is formed hollow
either through its entire length or a portion thereof, so that a tube or pipe inay be
passed through the hollow spindle and through the iron core into a hollow or oil
well formed in the core. The oil used in oiling the tubular pieces will find its way
into this oil well and can be withdrawn therefrom by the tube or pipe when
required. The wire of the armature is wound upon the drum in a special manner
which will be better understood if hereinafter described with reference to a diagram
on the accompanying drawings.
The fixed iron core may in some cases be wound with wire and there may be
substituted for the fixed iron core, a core made of thin iron plates insulated and
revolving with the armature.
And in order that our said Invention and the manner of performing the same
may be properly understood we hereunto append a sheet of explanatory drawings
to be hereinafter referred to and representing our improved arrangeinents. In
these drawings the same reference numerals are used to mark the same or like
parts wherever they are repeated.
One modification of our improved apparatus is shown in longitudinal section in
Figure 1 on the accompanying sheet of drawings, and in a cross section taken
through the armature in Figure 2. In this modification there is a fixed central
shaft or axis 1 which is arranged to be carried by two standards 2 at each end in a
convenient manner. This shaft 1 is formed with a bore or hollow 3 which extends
from one end to near the middle of the shaft where it joins a hole 4 bored through
from the underside of the shaft to its centre. On this shaft 1 over the hole 4 there
is fixed by screws a solid iron core 5 which has a longitudinal hole 6 formed.
through it underneath the shaft 1. This hole 6 extends through the core and is
plugged at each end being connected near its ends by short passages with a recessed

page_text: part 7 formed at each end of the core round the shaft 1. The hole 6 is connected
by a passage to the hole 4 which passage extends also downwards in the core being
plugged at its end. A tube or pipe passed through the hollow 3 in the shaft is
screwed into the narrower portion of that hole 3 and this pipe 1 is connected with
another short pipe fitted in the passage 4 and extending to near the bottom of the
oil well so that any oil used in lubricating which will have collected in the oil well
may be withdrawn as required. At each end of the core 5 there is fitted loosely
on the shaft 1 a tubular piece 8 one of which has keyed upon it a pulley 9 for
a driving belt. At the end of the tubular piece 8 nearest the core 5 it is formed'
with a collar or boss 10. Upon this end of the tubular piece 8 there is placed a
flat iron ring 11 having a rebate or recess formed round its circumference at its
outer edge. In this rebate there is fitted a corresponding rebate formed in a
narrow flat ring 12 made of insulating material. At the other end of the core 5
the tubular piece 8 is also formed with a collar or boss and has on it a metal ring 11
fitted by a rebate to a ring of insulating material the rings being held together by
screws, and the rings 11 are also fastened to the bosses by screws. The rings 12
at each side of the core 5 are connected together by paper (or other suitable
-insulating material) and thus a hollow drum enclosing the core 5 is formed. The
modification shown is arranged for four magnets which are placed in the usual
manner round the drum and core 5 (as indicated in Figure 2). The wire is wound
round or over the hollow drum in the following special manner which will be best
understood on referring to the diagram Figure 3 on the accompanying drawings.
The periphery of the drum is divided longitudinally into a number of equal parts
by strips preferably of non metallic material, although in some cases iron strips
may be used but they must be carefully insulated from each other and from any
part of the machine. The number of these strips will be any multiple of the
number of magnet poles + or -1. In the diagram the drum is shown as being
divided into 31 equal parts the machine having four magnet poles and on commencing
to wind the wire is taken from the connection with the commutator as at A to a
strip at 9, thence it is wound longitudinally along the drum over its end so as to
form at the end a chord of an arc of the circle of the drum and returns along the
drum at a part 9 strips from 9 namely 1. The wire is wound round and round in
this manner until half the equal space between the strips 1 and 31 and between 9
and 10 is filled up forming a coil and then the single wire is passed to a fresh
division 24 which is 7 strips apart from 1. Thence the wire is again wound round
and round from this point to a point 16, likewise 9 strips apart from 24 the wire
being wound back covering the single wire passing from 1 to 24 until the half of
that space is filled up when the single wire is led to a fresh division, 7 strips away
round the drum as before where the same operation is repcated. By continuing
this method of winding the whole of the equal spaces between the strips will be
filled in with the wire, and the armature will then be complete when the finish of
the winding brings the end of the wire at the division of the commutator where
the winding commenced and so making the winding of the wire on the drum
symmetrical. Each single wire crossing the end of the drum is connected in the
usual way to the commutator. Any number of wires may be wound over the first
one and they may be connected up either in series or in parallel. By this improved
method of winding the wire either two or four brushes on the commutator may be
used. In order to find the number of strips round the circumference of the
armature which will separate the point at which the winding of the wire is
commenced from the point at which it is passed forming a coil, it is necessary to
proceed in the following manner. The number of strips will be a multiple of the
number of magnets + 1 or -1. The multiple is taken and 1 added to it which
will give the number of strips that the coil B. C. encloses and the multiplier -1 is
the number from C to D that is left between it C and the next coil D, E and so on
round the circumference of the armature.
Figure 4 on the accompanying sheet of drawings represents a longitudinal
section of a modification of our improved arrangement of the armature of a dynamo

page_text: electric machine in which there is substituted for the fixed iron coro 5 of the first
modification a core of iron discs forming a solid cylindrical drum. Figure 5 is a
cross section taken through the armature and Figure 6 is an end view of the
armature. In this modification the body of the armature is built up of a number
of iron discs 13 which are fixed upon a tubular piece 14 of insulating material.
This piece 14 is upon a shaft or axis 1 which is carried in suitable bearings in
standards 2 and has fixed upon it a pulley for receiving a driving belt. The iron
discs are fixed upon the tubular piece 14 being insulated from each other by discs
of paper or other suitable material and are bolted together by screw bolts 15
between end plates 16 which are keyed upon the shaft 1. The wire is wound
round the cylindrical armature formed by the discs 13 in the same manner as
herein before described with reference to the first modification and the diagram
Figure 3. The discs 13 are formed with teeth round their edges which correspond
to the strips of insulating material dividing the drum of the first modification into
equal parts. These teeth when the discs are placed together form longitudinal
ridges and grooves along the cylindrical drum and into the grooves the wire is
wound as already described. If preferred the discs may be formed without teeth
and strips of insulating material or iron insulated placed on the armature formed
by the discs as herein before described.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed we declare that what
we claim is:-
:-
Firstly: The combination and arrangement of parts forming the improved
armature for a dynamo electric machine substantially as hereinbefore described
with reference to figures 1 and 2 on the accompanying drawings.
Secondly-The forming of the ends of the armature of dynamo electric machines
removable to give access to the core of the machine substantially as hereinbefore
described.
Thirdly-The method of winding the wire on the armature of a dynamo electric
machine substantially as herein before described with reference to the diagram on
the accompanying drawings.
Dated this 29th day of November 1884
15 Witness,
LOCK MOORE,
Patent Agent, Nottingham.
WILLIAM HARDING SCOTT.
EDUARD ALEXANDRE PARIS.