Improvements in Dynamo-electric Machines.
Year: 1894

page_text: Date of Application, 23rd Jan., 1894-Accepted, 24th Feb., 1894
COMPLETE SPECIFICATION.
[Communicated from abroad by GEORGE FREDERICK DIECKMANN,
No. 407, Sedgwick Street, in the City of Chicago, County of Cook,
State of Illinois, United States of America, Electrician.]
Improvements in Dynamo-electric Machines.
I, HENRY HARRIS LAKE, of the Firm of Haseltine Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention, and in what manner the same is to be
performed, to be particularly described and ascertained, in and by the following
statement:-
The invention designs to utilize the electric impulses developed through magnetic
induction at the internal circuit in the armature-coil of the familiar dynamo-
machine for the production there in a suitable secondary coil of an extra or
additional electric current which can be thence distributed for external use. In
brief, advantage is taken of the changes which occur in the condition of the
ordinary electric flow through the armature-coil to present for its inductive
influence, a secondary coil properly arranged and connected for the responsive
generation of supplemental current which may be sent into the external circuit
and there be utilized.
The exact nature of the improvement will appear from the description following
and be pointed out by claims at the conclusion thereof.
In the accompanying drawings forming part of the Specification like parts are
designated in like fashion throughout.
Figure 1 is a view in front elevation of a dynamo-machine constructed in
accordance with the invention.
Figure 2 is a detail view of the same in longitudinal section.
Figure 3, an analytic table displaying the electric actions and re-actions at
several successive stages during rotation.
Figures 4 to 7, diagrammatic views to show the electric play and re-action
between the primary armature and secondary helix at several successive stations.
In the structure selected, the improvement is shown as applied to an ordinary
dynamo of the Gramme type, the machine being properly modified as will appear,
to adapt the same for the effective generation of the supplemental current.
Upon the bed-plate A are mounted the standards a which afford journal
bearings for the revolving shaft C driven by pulley as at o. Uprights 6 secured to
the bed-plate constitute a part of the field electro-magnets B which extend laterally
therefrom and have like poles at their confronting terminals. Each field-magnet B
has an armature or keeper D, the same consisting of a core e preferably of cast iron
or iron wire overwound by an insulated copper wire or ribbon. The coil d is
disposed in familiar fashion about the entire core but is divided into separate
sections, these being joined at adjacent ends to neighbour sections so that the whole
series is connected in continuous loop. At the section joints a wire e leads thence
to the appropriate segment f of the insulated commutator ring E. Like coil-
sections of the dual armatures D here shown are connected up to the same
commutator segment f by the single wire e.
Close between the armatures D is located the secondary helix F, said helix
consisting of a core g preferably of wood or other non-magnetic material over-
wound by an insulated wire or ribbon (usually of copper) and divided into sections
looped together at adjacent ends, in exact keeping with the respective coil-sections
of the armatures D which stand opposite. A separate commutator G for the

page_text: helix F has its segments electrically joined to the respective loop-wires of adjacent
helix-sections. Each commutator E G has as many segments as there are separate
sections in the coils of the armature and helix. The brushes for the armature
are set as usual at the diameter of commutation. The brushes i for the helix G are
in two pairs, one pair being located (radially) in near position at the sides of each
armature-brush h and distant therefrom the space of one-half a commutator-
segment. That is, when brush his bridging, the helix brush pair i is at mid-length
of the adjoining segments.
Helix-core g is carried by spokes K extending from the companion hubs l, said
hubs being keyed to the drive-shaft C. The armatures D are sustained by wedge-
blocks m and discs n, the latter being threaded to the shaft C so that the armatures
are capable of nice adjustment to bring their coil-sections exactly opposite to the
corresponding sections of helix F. By which expedient the spires of the armature
and helix coils respectively stand substantially in confronting parallel throughout
and are thus in position proper for inductive play.
On revolving the shaft C it carries with it the two armatures D and helix F
together with the commutators E G pertaining thereto. The magnetic circuit is
established as usual between the field-magnet B and the armature or keeper-cores c.
As rotation proceeds such current is constantly cut by the spires of the coil D,
I generating therein through magnetic induction at the north and south fields,
simultaneous electric impulses of opposite course which are commutated at the
brushes and appear in external circuit as a flow of single direction. During one-
half of its, traverse any given coil-section is in the north magnetic field, for
instance, and during the other half is in the south field. The commutator brushes h
are set at the limits of the field, i.e., the neutral point and the section passes from
field to field at the brush contact with its segment. What one brush does for the
particular section, the other brush does for the opposite (or diametric) section at
the same time but in reverse. That is. to say, two opposite sections of the armature
coil are simultaneously changing their field relation and in consequence their
electric condition. But the change is not immediate. For when the brush first
contacts with the segment appropriate to the particular section, the brush then
spans between such segment and its retreating neighbour. At this bridging position
the brush diverts or shunts the electric flow around the section thereby rendering
it neutral or in other words, breaking the electric flow which before prevailed in
the section. Another moment and the brush is in sole contact with the selected
segment which means that the corresponding section is now fully established in the
new field so that the electric flow is resumed therein but is necessarily in direction
the reverse of that distinctive of the section when controlled from the opposite
field. Accordingly, there has been a break and then a reverse make of the electric
current through the section. Both of which distinct changes will tend to develope
derived impulses of like direction in a parallel secondary conductor properly
exposed to the inductive play. What occurs in the section at the north field
occurs simultaneously in exact counterpart in the opposite (or diametric) section at
the south field. The inductive actions at the two fields are (in direction) of
exactly opposite character. Advantage is taken of this fact to locate a secondary
wire in parallel at each point stated, thereby utilizing the inductive influence of the
armature coil-sections as these pass in succession to and from bridging position.
Since the derived impulses generated in the secondary conductors at the two fields
are simultaneous and opposite, and thus like the impulses existing by magnetic
induction in the armature cuil, resort is had to similar expedients for forcing out
the electrically induced currents so that these may appear in external circuit as a
flow of single direction.
Referring to the diagrammatic views (Figures 4-7) one of the armatures is
shown in conventional form surrounded by the secondary helix, like coil-sections of
each being displayed in confronting parallel position. The sections at both
armatures and helix are connected up in continuous loop, each loop wire being
separately joined as appears to one of the insulated segments in the commutators E G

page_text: as the case may be. The opposite brushes for the armature are located as usual ac
the diameter of commutation whilst the double pair for the secondary helix, range
as shown in radial position at the sides of the armature brushes the distance of one
segment apart so that the armature brush is mid-way between.
For simplicity, only one armature is exhibited especially since the electric
changes in that will stand exactly for the changes in the fellow armature as well.
Although the use of dual armatures in lieu of the single armature ordinarily
employed divides the total voltage between each armature, yet it reduces the
resistance in same ratio, and doubles the carrying capacity, so that ultimately the
watts out-put remains practically unchanged. The expense of the additional
armature is the only objection.
Station I. When the machine-parts are in position shown by Figure 4, the
electric current generated in the armature coil by magnetic induction passes (as
shown) through the positive brush h at the diameter of commutation and so by
wire into the external circuit, feeding a storage battery as at X and returning
thence by wire »² and negative brush h to the other side of the coil to complete its
traverse. At this juncture all of the armature coil-sections are in circuit, the
brushes being in contact with single segments only. Accordingly no inductive
action happens and the coil of the secondary helix stands neutral throughout, as
shown by its light lines.
Station II. Figure 5. The armature or primary brushes are now at the bridge
point and span between adjacent segments, the result being to shunt or cut out the
coil-section which pertains to the particular segment just brought into brush
contact. But the break of the (→) current at section x renders said section
inductively active, and the confronting section a' on the secondary helix is in proper
relation to be sensitized thereby. The derived electric impulse is the same in
direction (→) with the course of the current which has just ceased to flow in
section x.
But the opposite (or diametric) section " on the armature-coil has also
been shunted out simultaneously with section through the other armature-brush.
Since the current in section is the reverse (←) of that in section a, the derived
impulse at confronting helix section 13 will be the reverse (←) of that developed
in helix-section a'. The diagram (Figure 5) shows at the dark lines, the sensitized
helix sections and displays their connections with the respective brush pair at the
commutator. The brushes for the two opposite sections stand at about mid-length
of adjacent segments, and it appears that the respective positive and negative
brushes in each pair are joined to the same side of the distribution or external
circuit.
Station III. Figure 6. The armature brushes now leave the bridge point and
are in sole contact with the segments appropriate to sections 12. Said sections
again become active but the direction of the current therein is the reverse of that
which prevailed when the bridge was just to be made. The sections have changed
their position (electrically) from one field to the other. The inductive influence
of section x for example, in passing from neutral to active state, tends to develope
a secondary impulse of opposite course (→) to that of the primary flow (<).
But the impulse derived thereupon in confronting section a¹ is the same in direction
now, i.e., (→) as was the impulse therein at the moment of shunt or break. The
belix brush being still upon the proper segment for section delivers the additional
impulse to the external circuit. The reverse impulse (←) derived simultaneously
at the opposite (or diametric) section 1 passes by its controlling brush to the
same side of the line, so that the two impulses force out together as a current of
single direction.
Station IV: The armature brushes continue upon the segments to which they
are attained at Station III. No change in electric condition occurs in the armature
sections, and in consequence, no derived currents are developed in the secondary
helix. The brushes for the secondary helix are now at the bridge point and would
operate to destructively short-circuit the current if any were flowing which is not
the case.
The secondary brushes clear the bridge before the brushes of the

page_text: armature attain thereto at the next station. Hence, when the ensuing inductive
play arises in sections 1 through shunt or break of the current in the succeeding
armature-sections, the helix brushes are in position to deliver the derived
impulses, as before, to the external circuit.
Station V. There are 12 coil-sections shown, and necessarily, 12 commutator-
segments, with 12 insulating strips between, constituting XXIV stations in the
circuit. After XII stations passed each coil-section shifts its electric condition.
Succeeding sections accomplish the shift at successive bridge stations. The charge
for section a from (→ to O) and (0 to +) has been traced and the inductive
effects noted. Like changes repeat themselves for the twelve sections in turn.
After which section x changes back from (←) to (→) and persists therein through
the other XII stations. The structure and relations of the parts being symmetric
throughout, it is unnecessary to further develope the electric actions and re-actions.
Enough has been described to demonstrate that in the ordinary dynamo, the
internal circuit with its pole changes may be efficiently utilized to obtain an extra
or additional electric current through proper presentation of a secondary conductor
susceptible to the changes in polar status which distinguish the primary current in
the dynamo armature-coil. When the machine is used in reverse, i.e., as a motor
instead of a dynamo-electric generator, the intermediate secondary helix is still
retained and is employed as before to utilize the inductive play of the current
changes arising successively in the coil sections of what have then become the
revolving motor armatures D. Employed in either way, the inductive activity
exists and it is merely necessary to present the parallel helix coil within the field
of influence under conditions proper to force the extra current thereby derived into
the external circuit. In which view the term "dynamo as hereinbefore employed
is to be taken as equivalent to the term
"
❝ motor throughout.
Heretofore, it has been proposed to construct an electric machine wherein the
field magnet was provided between its poles with the familiar armature core to
complete the magnetic circuit. About the armature core was wound (1), the helix
proper and (2), a secondary coil each having its separate commutator and brushes.
Both helix and coil were equally exposed to the cut of the magnetic lines of force.
The object was to develop an extra current in the secondary coil by electric
induction ensuing upon break or shunt of the main current in the primary helix.
The cut of the magnetic flow was attributed to the primary helix only.
دو
The present invention contemplates the removal of the supplemental coil from
the field of magnetic force and to this end the coil is separately mounted from the
primary helix or drum core which remain as usual fully exposed in the magnetic
field. The aim is to derive the extra current in the supplemental coil through
pure electric induction by virtue of the proximity and parallelism of the coil and
the primary helix. So far as the coil is subjected to the cut of the magnetic flow
in common with the helix the influence is plainly detrimental and because of this
the separate mounting of the coil apart from the helix, as proposed, avoids the evils
which arose when the mounting of the parts named was in unison and upon an
armature core common to both.
Thus far the aim has been to display the simple inductive re-actions which occur
in successive sections of the helix coil on make and break or shunt of the current
in the confronting section of the primary armature. Observation shows however,
that any particular section of the armature-coil on crossing at the bridge point
from one field to the other experiences graduated changes in its electric condition
during the period of its traverse through the new field. Viewed from the negative
brush for instance as zero or minimum the symmetric sections at either side thereof
present a like electric status but of opposite course which status however differs
from neighbour sections and advances to a maximum at the positive brush.
These changes in electric status are of a nature which tend to generate an
inductive impulse in a parallel secondary wire and being always of one kind,
i.e. from minimum to maximum or else in reverse induce a current of single
direction in the confronting helix section during the period that both primary

page_text: Practically
armature and secondary helix sections remain in the same field.
therefore it is designed to have the corresponding brushes of the armature and
helix fall (radially) in substantial alignment. Which means that the dual sets of
helix brushes, as heretofore detailed, are to be replaced by single brushes oppositely
arranged and nearly aligned (electrically) at the diameter of commutation with like
single brushes of the primary armature.
By such provision one-half of the coil-sections in both armature and helix are
simultaneously in one field, as determined by the brushes, and the other half or
opposite sections are in the reverse field. Which provision enables the sections of
the helix to generate and discharge into external circuit the impulses of like
direction induced therein through the progressive changes in electrical status of the
confronting belix sections as these advance in the same field. This current is super-
added to that developed inductively by shunt or make and break as already fully
described the change in brush arrangement permitting all of the helix sections to
be involved in the inductive play. When dual brushes are used, as herein detailed,
it will be seen that no section is beneficially exposed to the inductive action by
progressive changes in electric status just set forth except only the single section
which for the time being is included in circuit.
The two helices i.e., primary armature and secondary helices, may serve as a
transformer and this too whether the electric supply be due to the presence of the
field-magnet or in its absence be sent into the primary from some other source. The
helices being of the Gramme type and the brushes aligned as already set forth it
becomes possible to utilize the inductive actions of primary upon secondary. Under
the term of a Gramme type of armature is understood an armature having a
continuous or endless coil divided into sections which connect to the different
commutator segments, including the open circuit armature and the corresponding
connections to the different segments.
Obviously the details of structure may be changed according to the mechanic's
skill, and various types of machine be used without departing from the spirit of the
invention which involves generally the presentation of a supplemental wire-coil at
the machine under conditions proper to utilize the inductive play arising by changing
the electric condition of the armature helix.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. In electric machines, the combination with the field-magnet and with its
armature helix of a supplemental coil mounted separately from but located parallel
to said helix and inductively influenced thereby, substantially as described.
2. In electric machines, the combination with the field-magnet and with the
armature having a helix thereon of a supplemental coil mounted separately from
said armature but parallel with the helix thereof and inductively influenced thereby,
substantially as described.
3. In electric machines, the combination, with the field-magnet and with the
armature having a helix thereon and a brush mechanism of a supplemental coil
mounted separately from said armature but located parallel with the helix thereof
and inductively influenced thereby, and a separate brush mechanism for said
supplemental coil to discharge into external circuit the derived electric current
generated therein, substantially as described.
4. In electric machines, the combination with the field-magnet and with the
revolving armature having a section-helix thereon and a brush-control mechanism
to progressively shunt the sections thereof of a supplemental or secondary
revolving section-coil mounted separately from said armature but located parallel
with the helix thereof and inductively influenced thereby, and a separate brush-
control mechanism for said supplemental coil to discharge into external circuit the
derived electric current generated therein, substantially as described.
5, In electric machines, the combination with the field-magnet and with the

page_text: revolving armature having a loop-coil section helix thereon and a brush-control
mechanism to progressively shunt the sections thereof, of a supplemental or
secondary revolving loop-section coil mounted separately from said armature but
located parallel to the helix thereof and inductively influenced thereby, and a
separate brush-control mechanism for said supplemental coil to discharge into
external circuit the derived electric current generated therein, substantially as
described.
6. In electric machines, the combination with the primary armature and secondary
helices of the Gramme type of the commutation brushes for said helices, in
substantial electric alignment with each other, substantially as described.
Dated this 23rd day of January 1894
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.