Improvements in Armatures of Dynamo Machines.
Year: 1891

page_text: Date of Application, 5th Jan., 1891
Complete Specification Left, 28th Oct., 1891-Accepted, 28th Nov., 1891
PROVISIONAL SPECIFICATION.
Improvements in Armatures of Dynamo Machines.
I ROOKES EVELYN BELL CROMPTON of the Arc Works Chelmsford in the
County of Essex Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in the armatures of dynamo machines more
particularly to those of which the armature is of considerable diameter and the
armature winding is that known as drum winding, that is to say that in which the
turns pass completely over the ends of the cylindrical core. In place of the crank
connecting pieces usually employed to connect two bars which form two successive
parts of a turn of the winding I place at each end a built up arrangement of
segments insulated from one another in a manner similar to the commutator or
collecting cylinder of a direct current dynamo. These I hereafter call segmental
heads. secure by soldering, brazing screwing or other suitable means the con-
necting pieces intended to connect the bars in their due successive order into these
segmental heads in two planes of rotation. In this manner the whole of the end
connections of the armature can be built up into their position on the two
segmental heads and these end connections can be slid into position complete as a
whole so that the bars forming the winding can then be secured to them by screwing
or soldering in the ordinary manner.
I prefer to mount the armature core of these machines in the following manner.
The thin sheet iron rings or discs which compose it are attached to radial bars in
the manner described in my Patent No. 4302 of 1884 but in this case instead of the
radial bars fitting at their inner edges into grooves formed in a boss on the spindle
itself, they fit into grooves formed on the outer end of the arms or spokes projecting
from a metallic hub or centre piece. The advantage of this arrangement is that
the radial bars may be made of non-magnetisable material and thus the lines of force
will be hindered from crossing the internal opening also that the discs being held
firmly connected at their inner edges by the radial bars can be detached as a
whole from the central hub which greatly facilitates the process of insulating the
core itself.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Armatures of Dynamo Machines.
I, ROOKES EVELYN BELL CROMPTON of the Arc Works, Chelmsford, in the
County of Essex, Engineer do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
My invention relates to improvements in the armatures of dynamo machines more
particularly to those of which the armature is of considerable diameter and the
armature winding is that known as drum winding, that is to say that in which the
turns pass completely over the ends of the cylindrical core.
In the accompanying figures Fig. 1 represents a longitudinal section of a complete
armature constructed in accordance with my invention.
Fig. 2 shows a portion of the armature core in plan and with some of the bars
forming the winding in position.

page_text: Fig. 3 shows an end view of the armature with the segmental heads and a few of
the end connections in position.
Fig. 4 shows a cross section through the centre of the armature core the bars
forming the winding end connections and segmental heads being omitted.
Figs. 5 and 6 show respectively an end connection and a method of attaching the
same to one of the bars forming the winding. In place of the crank connecting
pieces usually employed in drum wound armature to connect two bars which form
two successive parts of a turn of the winding I place at each end a built up
arrangement of segments insulated from one another in a manner similar to the
commutator or collecting cylinder of a direct current dynamo. These which I
herein after call segmental heads I secure by soldering, brazing, screwing or other
suitable means to the connecting pieces intended to connect the bars in their due
successive order into these segmental heads in two planes of rotation.
In this manner the whole of the end connections of the armatures can he built up
into their position on the two segmental heads and these end connections and
segmental heads together can be slid into position complete as a whole so that the
bars forming the winding can then be secured to them by screwing, brazing or
soldering in the ordinary manner. In Figs. 1 and 3, S S show the segmental heads
each one built up of a number of metallic segments equal to half the number of end
connections at the same end of the armature. These segments are insulated from
one another held between collars K on a bush B and in the manner well known to
those accustomed to the construction of commutators of dynamos.
One of the segmental heads has its segments prolonged parallel to the spindles
beyond what is necessary for the fixing of the end connections and the prolonged
portione serves as a commutator.
To each segment of these segmental heads are attached by soldering, screwing or
other suitable means two end connections EE shaped substantially as in Fig. 5 and
in such manner that their other extremities meet and are connected by soldering,
screwing or other suitable means, to the two ends of one of the pairs of bars W, a pair
of the bars W forming the winding and which require to be so connected. It will
be seen from Figs. 1 and 3 that when one set of end connections is fixed into its
segmental head there will be two groups of end connections in two parallel planes
and the whole can be slid into position in the spindle or hub.
When both sets of
end connections are in place the bars forming the winding Ware then laid in
place and have their ends attached to their respective end connections. Fig. 6 shows
a suitable method of making this attachment.
It will be seen that the use of these segmental heads to form the end connection
of the winding, gives great facility in construction and repair of drum wound
armatures, but that it does not lend itself readily to such cases where the armatures
so employed in dynamos having only one pair of poles, as in this last case, the end
connections having to be used to coune.t sections of winding nearly 180 degrees
apart, the segmental portions of the head must be necessarily of such small diameter
that it cannot be so advantageously used as the commutator of the dynamo, but
when the end connections are for dynamos having two or more poles, the full
advantages of the arrangement are utilised.
In addition to these last advantages the fact that the segmental heads can be
rotated relatively to one another on the spindle of the dynamo, gives great facility
for coupling up the segments of winding in various ways.
Turning to Fig. 3 it will be readily understood by those accustomed to the con-
struction of this class of machinery that if one segmental head be rotated relatively
to the other through an angle equal to the width of one section of winding, the
coupling up of the armature will be altered so that the two adjacent sections of
winding are in parallel instead of the whole being in series. By rotating it
through an angle equal to two sections of winding the coupling up will be three
parallel and so on.
I prefer to mount the core A of my improved armature in the following manner.
Th thin sheet iron rings or discs which compose it are attached to radial bars R in

page_text: the manner described in my Patent No. 4302 of 1884, but in this case instead of the
radial bars fitting at their inner edges into grooves formed in a boss on the spindle
itself, they fit into grooves formed on the outer end of the arms or spokes D
projecting from a metallic hub or centre pieces H. The advantage of this arrange-
ment is that the radial bars may be made of non-magnetisable material and thus the
lines of magnetic force will be hindered from crossing the internal opening also that
the discs being held firmly connected at their inner edges by the radial bars can be
detached as a whole from the centre hub which greatly facilitates the process of
insulating the core itself.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that I am
aware that it has been already proposed to use end connections consisting of radial
pieces and spiral strips fitted together, insulated and clamped by insulated rims and
metal clamping rims, and I make no claim to such arrangement of parts but what I
do claim is
1 The combination or arrangement and use of segments, collars and curved
connecting strips forming the segmental heads substantially as herein described to
form the end connections of drum wound armatures for dynamo machines or
armatures having four or more poles.
2: The arrangement of a pair of "segmental heads" connected by pairs or
sections of winding so arranged that the segmental heads may be drawn off
separately substantially as and for the purposes herein described.
3:-The construction and arrangement of the parts of armatures of dynamo
electric machines so as to facilitate the application of the "segmental heads" in
drum wound armatures, the building up thereon of the end connections and winding
and the general construction of such armatures, substantially as and for the purpose
set forth.
4: The combination or arrangement of parts of drum wound armatures of
dynamo electric machines, wherein the segmental heads are applied and the
bars forming the winding, and their end connections are disposed and connected in
two planes of rotation, substantially as and for the purpose herein set forth.
5: The construction, arrangement and use of armatures of dynamo electric
machines having their parts formed and connected, substantially as and for the
purpose set forth.
noth dow of October 1801
noth of October 1801
day
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.