IMPROVEMENTS IN DYNAMO-ELECTRIC MACHINES
Year: 1883

page_text: "3
LETTERS PATENT to Henry Harris Lake, of the firm of Haseltine, Lake,
and Co., Patent Agents, Southampton Buildings, London for an Invention of
"IMPROVEMENTS IN DYNAMO-ELECTRIC MACHINES A communication to him
from abroad by George Washington Fuller, of Norwich, Connecticut, United
States of America.
COMPLETE SPECIFICATION filed by the said Henry Harris Lake at the
Office of the Commissioners of Patents on the 14th March 1883.
"
HENRY HARRIS LAKE, of the firm of Haseltine, Lake, & Co Patent Agents;
Southampton Buildings London "IMPROVEMENTS IN DYNAMO-ELECTRIC MACHINES
Communicated to me from abroad by George Washington Fuller, of Norwich;
Connecticut, United States of America
This invention relates to the application to dynamo-electric machines having
cylindrical armatures, of an armature core independent of the induction coils
surrounding it, and held in unchanging polar relations to the field magnets by the
attractive force of the field magnets.
According to the present invention the armature core is of cylindrical form, and
is loosely mounted upon a rotating shaft, upon which the induction bars are
supported, and by which they are rotated, the field. magnets being stationary. The
said invention also comprises a special arrangement of field magnets in connection
with pole-pieces and a method of so connecting the induction bars, which traverse
the armature, with each other and with the commutator, that I am enabled to
avoid great elongation of the armature.
In the accompanying drawings
Figure 1 is a top view or plan of a machine constructed according to this
invention.
Figure 2 is a front end elevation, and
.
Figure 3 is a rear end elevation of the armature and the adjacent parts thereof.".
Figure 4 is a transverse vertical section of the line v, v, Figure 1.
Figure 5 is a longitudinal vertical section on the line w, w Figure 1.
Figure 6 is a vertical section on the line x, x, Figure 1...

page_text: Figure 7 is a sectional end elevation drawn to an enlarged scale, of the
commutator, brushes, and adjacent parts.
Figure 8 is a transverse section through one of the brush holders on the line z. z.
of Figure 7.
Figure 9 is a diagram indicating the mode in which the groups of induction bars 5
are by means of insulated rings at the end of the armature, connected with each
other, and with the commutator strips.
The machine represented in the drawings is intended for the generation of
currents large in quantity, but low in electro-motive force.
A is the bed of the machine which may be made of heavy plank or masonry
Two rows of standards B.b are arranged across the opposite ends of the bed A, to
which they are fastened by suitable bolts. Each of these standards is an iron bar
serving as a yoke-piece for one of the upper and one of the lower members of the
groups of longer field magnets C. C, c, c. These magnets have hollow cores, the
outer ends of which abut against the faces of the yokes, and their inner ends against
shoulders upon the pole-pieces D. d.
The yokes and cores are fastened to the pole-pieces by means of the bolts C², c²,
which at their inner ends screw into holes tapped in the pole-picces, and at their
outer ends project through holes in the yokes, or standards, and are provided with
a screw thread to receive the nuts C3 c³, by which the pole-pieces, cores, and yokes
are clamped together. Immediately within the group of longer field magnets are
arranged similar groups of shorter field magnets C. Ci c', cl, the cores of which are
also hollow, and abut against suitable shoulders on the pole-pieces D. d and
are secured in position by means of the bolts C, c, the inner ends of which.are.
screwed into holes tapped in the pole-pieces D, d while their outer-ends project:
through holes in the shorter yokes B', ', and are provided with screw threads for
the reception of the clamping nuts C5, co by which the shorter yoke-pieces and cores
are fastened to the pole-picces.
The upper and lower poles of the field magnets are made up of separate sections.
The sections D', D2, D3, D4, D5, D6. composing the upper pole, are clamped together
by the horizontal bolt E, and the sections d¹, de, da, d, ds, de composing the lower
pole, are clamped together by the horizontal bolt e. Each section of each pole has
bolted to it, upon each side, a pair of superposed magnets, each pair composed of
one of the longer magnets and one of the-shorter magnets, It will be seen
therefore, that each two sections which are in vertical alignment constitute part of
a field magnet. frame, the other parts of which consist of the cores of four pairs of
the longer and shorter field magnets C, C¹. c c¹ the four yoke pieces B, B¹, b, b, to
which the other ends of the field magnets are respectively secured, and the tie
plates FF, to which the opposed edges of the sections are respectively secured by
the screws f, f. The drawings represent a machine having six of such magnet frames,
suitably secured in parallel planes. It will be understood that a larger or a smaller
number of such magnet frames may be employed, if desired, the dimensions of the
other parts of the machine being correspondingly altered as may be required.
The sections composing the poles are crescent shaped, and their opposed faces are
curved concentrically with relation to the axis of the rotating cylindrical cage,
composed of the parallel induction bars G,.supported in equidistant groups of five
upon the peripheries of three rotating wheels G1, G2, G3, the hubs of which are
secured to the rotating shaft H. The induction bars are insulated from each other,
and from the wheels upon which they are supported, and are held in position by.
the clamping segments g³ g² 9³ which are severally secured by screws g inserted
through the clamping segments, and into the peripheries of the supporting wheels
GGGs respectively. To afford clearance for the clamping segment g? and the
screws g which fasten the clamps to the periphery of the wheel G² the middle pair
of magnet frames are separated by means of the washers G which are interposed
between the pole-pieces D³ and D₁ and d³ and d respectively, through which the
bolts E and e respectively pass.
The core of the armature is divided into two sections by the interposition of the

page_text: wheel G.these sections are respectively composed of the short hollow cylinders of
iron, I. I, I, I³, and i, i¹ i³ which are supported by the arms J, J', J, and j, j', j²,
projecting readily from the hubs J³. J¹ J³, j³, j, j³, mounted upon the sleeves h, h¹,
which loosely enclose the armature shaft H so that the shaft H may be rotated
without rotating the sleeves h, h¹. The outer portions of the radial arms J, J¹ J?,
,,, are interposed respectively between the cylinders I. I' I2 I³ i i¹² i³, and are
perforated to receive the bolts Kk which are inserted through suitable holes in the
shells of the cylinders, and are provided at their outer ends with the nuts K³, K²;
kk by means of which the cylinders are clamped to each other, and to the ends of
the radial arms.
The armature shaft His provided with the bearing H¹ at the rear of the machine,
and is prolonged to receive a driving pulley, if the machine is driven by a belt, or
to receive a crank when the machine is driven by direct connection, with the piston
of a steam engine. At its front end the shaft H is provided with the bearing H
which projects sufficiently far from the wheel G³ to afford room for the commutator
M and the nests of concentric connecting rings N, to which the front ends of the
induction bars G are appropriately connected. Similarly the bearing H', at the rear
end of the machine is sufficiently distant from the wheel G' to afford room for the
nests of connecting rings n to which the rear ends of the induction bars G are;
appropriately connected.
±
The induction bars G are arranged in twenty four groups O, O, O, each composed
of five bars. The bars of the diametrically opposite groups are in each case
electrically connected with each other in series, so as to leave two terminals, which.
are respectively connected to two diametrically opposite strips of the commutator M.
As there are twenty four terminals for the groups of induction bars, the commutator.
is provided with twenty-four insulated strips m. The appropriate electrical
connection of the bars of each group with the bars of the diametrically opposite
group is effected by means of insulated rings at the ends of the armature. There
being one hundred and twenty induction bars, there are required at the rear end of
the armature sixty connecting rings. Fifty-six of these rings are arranged in eight
parallel vertical planes, each plane containing a nest of seven rings. The remaining
four rings are affixed to a sleeve mounted upon the commutator shaft. Each ring
has affixed to it, on opposite sides, two outwardly projecting connecting arms, the:
ends of which are fastened respectively to the rear ends of two of the induction
bars of two diametrically opposite groups. The connecting arms have the same
solid cross area as the induction bars, but the rings have one half the solid
cross area. As will be seen, they are flattened rings and they present two
paths right and left, for the current from one arm to the other, the sum of the cross
areas of which is equal to the cross area of one induction bar.
The relative positions of the nests of connecting rings are shewn in Figure 5, in
which it will be seen that the members of the three pairs of interior nests are
placed in close proximity to each other, so that the connecting arms can be arranged
in four parallel vertical planes. The fourteen connecting arms, (seven on
each side of the shaft,) attached to the innermost nest of rings are fastened
to the outer faces of those rings. The fourteen connecting arms attached
to the second nest of rings are fastened to the inner faces thereof, two
other connecting arms being carried inward through the first and second
ñests of rings, and fastened on opposite sides, respectively, to the periphery
of the ring on the shaft.which is in line with the space between the first and second
nests of rings. Similarly the fourteen connecting arms attached to the third nest of
rings are fastened to the outer faces thereof and the fourteen connecting arms
attached to the fourth nest of rings are attached to the inner faces thereof, the two
additional arms in that case, as before, being attached to the ring in line with the
space. between the third and fourth nests of rings. Again, the fourteen connecting
arms of the fifth and seventh nests of rings are attached respectively to the outer
faces of those rings, and the fourteen connecting arins of the sixth and eighth nests
of rings are attached to the inner faces thereof; the additional connecting arms in

page_text: each case, as before, being attached to the rings in line with the spaces between the
fifth and sixth, and seventh and eighth, nests of rings respectively.
On the front end of the machine, the twenty-four terminals of the various groups
of induction bars are connected with the commutator strips, and hence at the front
end of the armature twelve less connecting rings are required, or forty-eight in all.
At the front end therefore there are eight nests each consisting of six rings.
The manner in which these connections are effected is illustrated in Figure 9,
which is a diagram representing the front end of the armature and the commutator
strips, indicating in full lines the connecting arms by which the front ends of the
induction bars are connected to their appropriate rings and to the commutator
strips, and indicating in parallel dotted lines, in close proximity to the full lines,
the connections of the rear ends of the induction bars with the rings at the rear
ends of the armature. The nests of rings at the rear end of the armature are
numbered 1, 2, 3, 4, 5, 6, 7, and 8, respectively; and the rings upon the shaft are
numbered respectively 1 1-2, 3 1-2, 5 1-2, and 7 1-2 The nests of rings at
the front end of the machine are numbered respectively 11, 21, 3, 4, 5, 6, 71, and 8',
and these figures adjoining the arrow heads at the ends of the full and dotted lines
respectively in Figure 9, indicate to which nest the rings to which the connecting
arins are attached respectively, belong, and also the positions of the said rings
relatively to the other rings in the nests of which they are respectively members..
It will be seen that by this mode of connection' all the commutator strips upon
the lower side of the neutral plane are of one polarity, and all the.commutator
strips upon the other side of the neutral plane are of the opposite polarity.
Collecting brushes q are therefore arranged to bear upon all the strips, both above:
and below the neutral plane, as shown in Figure, 7.
The
The brushes are carried respectively in suitably insulated segmental brush
holders Q, Q1, Q2 Q3, which are suitably insulated from the adjacent parts of the:
machine, and are electrically connected respectively with the binding posts Rr, as
seen in Figure. 2, to which the terminals of the outside circuit are connected.
cominutator brushes are literally brushes with flexible wire teeth. The segments
in which the teeth are supported are made capable of radial adjustment by means
of the slots in the cars q', through which are inserted the bolts q2, by which the
segmental brush holders are screwed to a supporting disc q³ fastened by means of set-
screws upon the inner end of the box in which the armature shaft has its bearing H.
In operation, the cylindrical core of the armature is held stationary by the
magnetic attraction of the field magnets, and to ensure that the shaft H will turn
freely in the sleeves h and h¹ without imparting rotation to them, each of these
sleeves has formed in its lower portion a longitudinal oil cavity S. Strips of
cotton wick are laid edgewise in the cavities S. The upper edges of the strips bear
respectively upon those parts of the periphery of the shaft H surrounded by the
sleeves hh, which as will be seen are of larger diameter than the adjoining portions
of the shaft H. The ends of the cavities S are closed by means of plates which
are bolted to the ends of the sleeves hh' respectively.
The parts of the shaft enclosed by the sleeves hh', are oiled, and oil is applied to
the cavities S, through the tubes S', S', inserted into the upper ends of the holes a¹¹
bored through the sleeves h¹ respectively. These holes are inclined to the radius
of the shaft, as shown in Figure 4, in which the direction of rotation of the shaft H
is indicated by the arrow H³.
Owing to the enlarged diameter of the parts of the shaft surrounded by the
sleeves hh, the effect of centrifugal force is to keep the oil upon the periphery of
the enlarged portion, and to prevent it from spreading lengthwise upon the
adjoining parts of this shaft which are of smaller diameter.
Having thus fully described the said invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim
..
5
First. In a dynamo-electric machine having stationary field magnets and

page_text: a cylindrical armature, a rotating system of induction bars, arranged in the form of
a cylindrical cage and loosely surrounding a stationary cylindrical iron core.
Second. In a cylindrical armature, for a dynamo-electric machine, provided with
longitudinally circumposed groups of induction bars, a series of nests of insulated
connecting rings at each end of the armature for effecting the electrical connections
of the induction bars with each other, substantially as described.
Third. A cylindrical armature for a dynamo-electric machine, having a stationary
iron core, and provided with a rotating system of induction bars or coils suitably
connected with each other and with the commutator strips, and supported upon the
peripheries of two or more wheels independent of the said iron core, and having a
common axis of rotation.
Fourth. Two systems of brushes, the brushes of one system bearing upon, and
forming an electrical connection with, all the commutator strips upon one side of
the neutral plane, and the brushes of the other systein bearing upon, and forming
an electrical connection, with, all the commutator strips upon the opposite side of
the neutral plane, in combination with rotating induction coils or bars connected
with each other and with the commutator, substantially in the manner described,
whereby all the strips upon one side of the neutral plane are of one polarity, and
all the strips upon the other side of the neutral plane are of the opposite polarity.
Fifth. The devices herein shown and described for effecting the lubrication of-
the portions of the revolving shaft H within the loose sleeves h and h¹; each of
the said devices consisting of the oil supply hole s', extending through the upper
part of the sleeve; the oil cavity S, formed in the interior surface of the sleeve,
and containing a strip of fibrous material; and the enlarged part of the shaft
which the sleeve surounds.
In witness whereof I the said Henry Harris Lake have hereunto set my
hand and seal this fourteenth day of March in the year of our Lord
one thousand eight hundred and eighty three.