IMPROVEMENTS IN DYNAMO AND MAGNETO-ELECTRIC MACHINES FOR GENERATING ELECTRIC CURRENTS TO PRODUCE LIGHT OR ILLUMI- NATION, AND FOR ELECTRO PLATING, AND FOR OTHER PURPOSES USEFUL IN THE ARTS, INCLUDING IMPROVEMENTS IN MACHINES OR APPARATUS, AND IN MEANS, MODES, AND PROCESSES CONNECTED THEREWITH
Year: 1879

page_text: PROVISIONAL SPECIFICATION left by Arthur Wellsley Lake at the Office
of the Commissioners of Patents on the 8th April 1879. A communication
from abroad by Nathaniel S. Keith, of New York, in the United States of
America, Electrician.
ARTHUR WELLSLEY LAKE, of No. 66, Gloucester Gardens, Hyde Park, London,
in the County of Middlesex. "IMPROVEMENTS IN DYNAMO AND MAGNETO-ELECTRIC
MACHINES FOR GENERATING ELECTRIC CURRENTS TO PRODUCE LIGHT OR ILLUMI-
NATION, AND FOR ELECTRO PLATING, AND FOR OTHER PURPOSES USEFUL IN THE
ARTS, INCLUDING IMPROVEMENTS IN MACHINES OR APPARATUS, AND IN MEANS,
MODES, AND PROCESSES CONNECTED THEREWITH." A communication from abroad
by Nathaniel S. Keith, of New York, in the United States of America,
Electrician.
The object of my Invention is to simplify and cheapen the construction of
dynamo and magnetio electric machines, increase their electrical capacity or working
power, lessen the cost of the mechanical or driving power employed for rotating
the machine, and make the electric currents more nearly continuous; my improve-
ments in magneto and dynamo-electric machines being based upon certain
discoveries made by me while watching the movements and working of such
machines, the cost of construction, inadequate results, and expense of running the
machines as made by others being due to the fact that the makers of them have
not as yet made the discoveries which I claim as original with me, and upon which
I found my Invention of improvements in dynamo and magneto-electric machines,
my aforesaid discoveries being, first, that in magneto and dynamo-electric machines
of the type herein considered, and within parts of the electric circuit thereof there
exist electrical currents that have an opposite direction to the main currents of the
machine; second, that to the existence of these opposing currents within the
electric circuit and their retention therein are to be attributed the defects herein-
above mentioned, viz., undue cost of constructing the machines, inadequate results
from their working, and the cost of running them; and third, that by diverting
the opposing currents aforesaid into an external or outer circuit or "shunt" formed
with a rotary circuit-maker and breaker, the imperfections aforesaid may be
corrected and overcome.

page_text: My improvements herein set forth relate to that class of machines for generating
electricity wherein "armatures," that is to say, cores of iron surrounded by coils of
wire are rotated between the poles of electric-magnets, the currents of electricity in
the armatures and magnets being generated therein by induction.
Specifically, my improvements are as follows to wit:-
First. Improved forms, as hereinafter described, of the armature space enclosed
by and between the pole faces of the electro-magnets of magneto and dynamo
electric machines.
Second. Improved forms of armature cores, as hereinafter described.
"
Third. A rotary automatic "circuit maker and breaker," as hereinafter described.
Fourth. Combining a rotary circuit maker and breaker, as aforesaid, with an
outer or external circuit or shunt," so arranged as to divert or draw out of the
main circuit the opposing currents hereinabove mentioned, and by this means
neutralizing their evil effects, as hereinafter described.
IMPROVED FORM OF ARMATure Space.
As ordinarily made the armature space of dynamo and magneto electric machines
is circular in correspondence with the circle described by the rotation of the
armature, the circle formed by the shape of the magnets being necessarily some-
what larger than that described by the rotating armature but concentric thereto.
But I find an advantage in so shaping, combining, and arranging the parts of the
electro-magnet as to produce an armature space, a greater cubical area than the
concentric space aforesaid, the form of the space and its enlargement being such as
to cause the changes of magnetism in the cores of the armature and of the electro
magnet to be less sudden and intermittent, or in other words, to be as nearly as
possible continual, varying constantly during the rotation of the armature between
the poles of the magnets in regular rise and fall; the size and shape of the armature
space aforesaid being always dependent upon the special mode of constructing the
machine in each case, that is to say, the form of the armature space will be in
accordance with the style of machine; one style producing a space somewhat
approaching that of an ellipse, other styles giving rise to various polygonal forms,
such as hexagons, octagons, oblongs, squares, or otherwise, the distinguishing feature
of this part of my improved construction consisting in this, viz., that whereas the
armature faces of the armatures of ordinary construction rotate in a circle con-
centric to that formed by the pole-faces of the electro-magnets, and thus at an
unvarying distance from such pole faces, except at the points of magnetic change or
neutral line, thereby producing the abrupt and sudden changes of polarity
observable in machines of ordinary constructions, no such sudden and abrupt
change occurs in my improved machines for the reasons above set forth; as to the
enlarged armature space, such enlargement, whatever its final shape, being made
from the shortest to the longest diameter of such space with a consequent regular
rise and fall, as above stated, the magnetism of the armature faces during their
movement from the points of greatest nearness becoming gradually less by reason
of the constantly increasing distance between the armature and magnet faces until
the neutral line is reached, by which time the armature core nearly minus it
previous magnetism is ready to take on the magnetism of opposite polarity and by
as gradual a process of reception.

page_text: improved form of armature consists in dispensing altogether with the enlarged faces
of the armature cores as made by others, and instead thereof I make the pole ends
of my improved armature cure not greater in area of section than the body of the
core and sometimes even less.
ROTARY CIRCUIT MAKER AND BREAKER, SHUNT, & OPPOSING CURRENTS.
As my improvements in dynamo and magneto-electric machines, with reference
to the opposing currents hereinabove mentioned, have relation to the rotary circuit
maker and breaker and shunt aforesaid, I now proceed to describe them in their
relation to and connection with each other in order the more clearly to set forth the
nature of each and my improvements therein.
As already observed, there exist in dynamo and magneto electric machines
currents of electricity generated in the coils of the electro-magnets that have a
direction contrary to those which are used externally. These currents act as
counter-force and resistance, requiring much mechanical power to overcome and
counteract their effects, and by reason of which an excessive heating of the machine
also takes place. The machines made by others retain these opposing currents'
within the electric circuit, with their attendant evils, whereas by my discovery, as
already hereinabove declared, I not only remove these opposing currents with
their ill effects, but I also utilize them when so removed. For this purpose I
provide a shunt as aforesaid, the electric circuit in which is closed and opened
by a rotary circuit maker and breaker, which I fasten to the axial extensions of
the armature core. This shunt in its parts consists of materials which are con-
ductors of electricity, viz., wires, connections, circuit-maker and breaker, and springs
or "brushes," to press upon the rotary circuit-maker and breaker. The "shunt," as
has been previously stated, is an outer circuit external to the main one, the ends of
the shunt being connected one with the positive, and the other with the negative
ends of the coils of the electro-magnet (as will be hereinafter more fully explained by
means of diagrams in my Final Specification). During the existance of the opposing
currents the shunt is closed by the rotary action of the circuit-maker and breaker,
with the result of diverting such currents into the shunt out of the main circuit, so
lessening materially the excessive heating that would, but for this diversion of them,
take place. The currents thus diverted into an outer or external circuit may now
be utilized for working purposes in the same manner as the currents of the main
circuit, whether for electro-plating, electric-lighting, or otherwise, which utilization
of the opposing currents I claim as an important part of my Invention.
ROTARY CIRCUIT-MAKER AND BREAKER.
This device is a wheel or cylinder fastened upon the axis of the armature, and
may be solid or otherwise, and made of non-conducting materials or otherwise.
Upon the periphery of this wheel or cylinder I secure curved plates of metal, all of
equal size.
These plates in number are double the number of the pole ends of the
armature to which they are attached; alternate plates being electrically connected,
while intermediate plates are electrically insulated from each other, and from all
other parts of the instrument; brushes or springs connected with other portions of
the shunt are then connected with and caused to press on this instrument at points
diametrically opposite to each other. During the existence of the opposing currents,
while the wheel is rotating, the brushes press on the alternate plates, and upon the
intermediate plates at other points of the wheel's rotation. By means of a rotary
circuit maker and breaker thus constructed, and combined with a shunt as aforesaid

page_text: and connected as aforesaid with the main circuit of a dynamo or magneto-electric
machine, the opposing currents hereinabove mentioned may be made to flow in a
constant direction in the shunt-circuit though intermittantly. These opposing
currents exist in the magnet-coils during that portion of the rotation of the
armature in which the armature poles are leaving the magnet-poles. And my
Invention of the rotary circuit-maker and breaker combined with a shunt or
external circuit as hereinabove described is also applicable to the magneto and
dynamo electric machines of ordinary construction, as made by others, which
application and combination I also claim as part of my Invention.
ELECTRIC LAMPS OR REGULATORS OF ELECTRIC LIGHT.
My Invention, in constructing the apparatus for regulating the production of
light from electricity generated by the means hereinabove described relates to that
class of "lamps" wherein the machinery or machinacal devices made use of to "feed"
the carbon points is controlled by a small electro-magnet or magnets which form
parts of the lamp machinery, the object of my Invention being to cheapen and
simplify the construction, and at the same time to secure regularity of feed motion,
and at needful periods, the parts and arrangement of the parts of the lamp con-
stituting my Invention consisting of a wheel provided with two drums upon its
axle, one drum on each side of the wheel, the diameter of one of the drums being
double that of the other, a chain, belt, or band, attached to each drum by one end,
and to the carbon carriers or holders at the other end, one of the holders being
heavier than the other, a pressure lever, a small electro-magnet, a spring, and a
jointed arm made with a toothed end. These mechanical devices, together with
their arrangement and combination, form a mechanism that produces an electric
light much more steady and free from winking, blinking, and hissing, than any of
the machines heretofore made by others.
The diameter of the aforesaid wheel depends in some measure upon the size of
the lamp; the one actually made by me was five and a half inches in diameter, the
length of the pressure lever about six inches, this lever bearing against the face of
the wheel at about midway of its length. The fulcrum of the lever is situated
between the bearing points aforesaid and the electro-magnet; the spring or counter
force to the magnet is at the end of the lever opposite to the magnet, from which
end, and standing at right angles thereto is the jointed arm aforesaid, the end
opposed to the joint being formed with a tooth to engage with the face of the
wheel when such face is serrated, the means of engaging and disengaging it being a
curved slot made in the end of the arm to work upon a fixed pin.
The action of this machine is as follows, viz. :-On closing the electric circuit the
electro-magnet of the lamp draws down the magnet end of the pressure-lever,
which raises the opposite end with its jointed toothed arm; the raising of this end
where the curved slot is situated causing the tooth by its movement against the
fixed pin to engage with the serrated face of the wheel, so moving the wheel and
separating the points of the carbon pencils by the action of the bands or chains
upon the drums of the wheel, thus establishing the light arc. At this point the
pressure lever, acting as a break, stops the motion of the wheel in either direction
until the strength of the electric-magnet having decreased allows the attracted end
of the lever to rise again, the wheel now moving in an opposite direction because
of the weight of the heavier of the carbon holders as aforesaid; this movement now
decreases the length and resistance of the light arc, as the former movement had
increased it, and correspondingly increases the current of electricity, increasing con-
sequently the strength of the electro-magnet to such an extent as to again attract
the magnet end of the lever, again producing the former pressure against the face
of the wheel; a constant repetition of these mechanical movements in connection
with the electrical currents aforesaid combining to produce a steady and clear light
from the burning carbon points.

page_text: The principal upon which I construct the mechanism hereinabove described is
based upon the following reasoning, viz. :-First, as the attractive power of
magnetism is in inverse proportion to the square of the distance of the matter
attracted, it follows that that power of attraction which permits the movement of
matter away from the magnet by a counteracting force is incapable of drawing the
removed matter back again from the increased distance in opposition to the same
force; second, if the force exerted in moving matter away from a magnet be
sufficiently decreased at the point of greatest distance to more than compensate for
the decreased attraction due to the distance, then the matter will again move
towards the magnet; third, a point mid-way upon a line drawn from the apex of
one serration to that of the adjoining one upon a serrated wheel is nearer to the
centre of the wheel than the apex of a serration.