IMPROVEMENTS IN DYNAMO MACHINES AND LAMPS CONNECTED THEREWITH
Year: 1883

page_text: LETTERS PATENT to Sydney Pitt of Sutton in the County of Surrey for an
Invention of "IMPROVEMENTS IN DYNAMO MACHINES AND LAMPS CONNECTED
THEREWITH Communicated to him from abroad by Leo Daft residing at
"
Greeneville in the State of New Jersey United States of America
COMPLETE SPECIFICATION filed by the said Sydney Pitt at the Office of
the Commissioners of Patents on the 1st May 1883.
33
SYDNEY PITT of Sutton in the County of Surrey. "IMPROVEMENTS IN DYNAMO
MACHINES AND LAMPS CONNECTED THEREWITH Communicated to me from
abroad by Leo Daft residing at Greeneville in the State of New Jersey United
States of America
This invention relates to an improvement in dynamo machines and lamps con-
nected therewith, especially applicable to forming are lights, but the dynamo
machine may be used for other purposes and may be also used as a motor.
The improvement in dynamo machines relates to a new and simple construction
of armature by which the same may be readily and cheaply made and it also
relates to a method of concentrating the magnetic force of the field magnet
immediately upon the wires from which the electricity is to be derived. The
invention is applicable in many forms of winding, and I do not limit myself to any
specific manner of winding.
The invention will be readily understood from the accompanying drawings of
which,
Figure 1 is an elevation partly in section, of a magnet and armature illustrating
the improvement and different methods of winding, and
Figure 2 is a view at right angles to Figure 1, partly in section and partly in
perspective.
In the form of armature shown A represents an iron ring having cast or otherwise
fixed upon it the dividing iron sectors F.
Within these sectors are placed the dividing angular projections G preferably
made of some non-magnetic material such as that known as vulcanized fibre "The
15

page_text: metallic portion of the armature is circumferentially grooved by the grooves Jas
shewn, which both prevent lateral currents, and also serve to cool the armature.
The ring is supported upon a double spider frame B, revolving about the
journal C, and provided with arms L which are attached to the metallic portion of
the ring preferably on the flattened sectors K as shown. The ring revolves
between the poles of a field magnet I of any suitable construction.
In winding the ring I interpose circumferentially, and in some cases laterally,
plates of iron between the coils of the ring. H represents generally coils of wire
properly wound between the dividing sectors F. G. as shewn. In the form of
winding shewn in the upper part of Figure 1, a dividing plate is first placed in the
groove extending radially in the direction in which the core is to be wound. A
layer of wire is then wound next to the iron of the armature.
Plates E are then interposed between this coil and the next. Other plates are
then interposed so as to divide each coil from the one next above it by such plate.
These dividing plates may be placed both within, and without the iron ring A, but
it is preferable to place them only upon the exterior of the armature.
A dividing plate between each successive coil is preferably employed as shown
at E, but a beneficial result may be obtained from the use of one or more of such
plates as shown at E' on the right of Figure 1. By interposing these plates
between the successive coils, a concentration of magnetic force is obtained in those
plates which produces a largely increased efficiency in the machine, but the
essential feature of its utility is the concentration of the magnetic field produced
by the field magnet in immediate proximity and relation to the wires of the
armature. It is plain that this method of interposing plates of magnetic material
between the coils is applicable to other forms of armature besides that shown, and
that the beneficial effects of the interposed magnetic material can also be
experienced when the armature is a part of a motor as well as when it is used in a
dynamo machine.
Various forms of lamps are shewn which may be connected with said dynamo.
The first of these consists in combining with the axial magnet of an electric lamp
an interior moveable coil attached to the core of the axial magnet. This interior
coil is placed in a shunt circuit around the circuit passing through the coil of the
axial magnet. The invention also consists in a new and simple arrangement of
magnetic clutch, the said clutch being attached to the core of the axial magnet
and being influenced by the varying magnetism of said core.
This invention is illustrated in the accompanying Drawing Figure 3 which
represents a vertical section.
In this Drawing the letter A designates an axial magnet, B its soft iron core
and C the carbon holder which extends loosely through the core and is connected
to the same by the rings a. a. which embrace the carbon holder, and each of which
is connected to a lever D. These levers are connected to an insulating frame or
support B, or the core B by pivots b and their upper ends are made concave to
correspond to the circumference of the core and they form armatures which are
attached by the core whenever the same becomes magnetized. To the core B is
firmly secured a plate P, which rests upon springs Q for the purpose of balancing
the weight of the core. The carbon holder is guided by grooved rollers r, r.
long as the electric arc remains in its normal condition, the attraction of the core B,
on the armature D retains the carbon holder firmly in position but whenever the
attractive force of the core decreases, the armatures D. release the carbon holder so
that the same slides down. As soon as the proper electric arc is restored the
downward movement of the carbon holder is again arrested and in this manner the
electric arc is controlled automatically.
As
In the core B, is a recess c, and in this recess is situated a regulating helix E
This belix is situated in a shunt circuit around the main belix A, and it is made of
very fine wire so that the resistance is much greater than that of the main helix,
the proportion being about 75 to 1, so that by far the largest portion of the current
nasses through said main helix.

page_text: The regulating helix E is wound in a recess formed in the moveable core and is
located in a shunt around the arc, it is so wound and connected that when owing
to the abnormal resistance of the arc more of the current flows through it than
through the main helix it will induce magnetism to the moveable core B of opposite
polarity to that induced by the main helix A.
The length of the arc is regulated as follows:-
The weight of the core being nearly balanced upon the springs Q, the tendency
of the main helix A, is to draw up the core B and with it the upper carbon thereby
lengthening the arc and increasing the resistance at that point the effect of which
is to direct a portion of the current through the smaller helix which being of
opposite polarity operates by opposite induction to weaken the lifting power of the
main helix, so that the core will drop and the carbons will approach until the normal
length of the arc is reestablished.
If from any cause more than the intended quantity of current flows through the
main helix A, the tendency would be to momentarily increase the length of the
arc, but as that increases the resistance more current will flow through the opposing
helix E and as the increased magnetism A, in the moveable core B, is met by a
similar but opposite force from the helix E, any appreciable permanent change in
the arc is prevented.
A clutch has been heretofore provided which moves with the core of an axial
magnet, the said clutch being adapted to be operated by magnetic repulsion instead
of by magnetic attraction as is shewn in my lamp. It is found in practice
impossible to operate by magnetic repulsion because when the core is very
magnetic, instead of repelling the clamp it will attract it just as a greater magnet
will attract a lesser magnet whichever pole of the lesser magnet be presented to the
more powerful one.
In Figures 4. 5 and 6 is shown a modification of the previous lamp and relates
to an improved means of regulating each lamp in a series independently of the
others, and is designed to accomplish the same result as the supplemental regulating
helix in ordinary use.
In this lamp the improved automatic regulator takes the place of the supple-
mental regulating coil shown in the other arrangement.
By this improvement a certain amount of the magnetizing helix is short
circuited or shunted out of the controlling current whenever the carbons become
too widely separated thereby preventing any further separation of the carbon.
The invention will be readily understood from the accompanying Drawings in
which
Figure 4 is a sectional elevation of the improved regulating apparatus.
Figure 5 is a detached sectional view showing one of the connections and
Figure 6 is a perspective view of the clutch device.
A represents the usual attracting coil, B the hollow core, C the carbon holder
held by the clutches described previously D represents a sliding contact, preferably
a spring contact which is carried by but insulated from the core B and is arranged
to make contact with the plates a. b c. d. e. and f in succession as it is moved
upward These plates are shown arranged upon an insulating support E-These
plates are connected successively with the coils of the magnet A. A detail of the
method of connecting is shown in Figure 2 in which the plate a is shewn connected
by the wire g, passing through the coil-cover h to the outer coil a¹ of the coil A.
The plate b, is similarly connected with the next interior coil, and so on through
the series.
Now it will be obvious that in order that the magnet A exert its entire force,
the electric current must pass through all its coils. This will be the case when the
core B has so far dropped as that the spring D, is clear of the plate b. As however
the attraction moves the core B, upward, the spring D comes in contact with the
plate b, thereby shunting out the outer coil A, and preventing the further upward
movement of the core and at the same time reducing the magnetic effect of the
coil A, and lessening the tendency of the magnetic clamps D' to clutch the carbon

page_text: holder C. If the core B continues to rise, it will gradually shunt out all the
coils A and thereby prevent any magnetic influence upon the core B. I have
shewn all the coils of A connected with independent plates, but this would probably
not be necessary. Neither is it essential that each coil should be independently
connected for the plates a. b. c. d. c. and f might be connected at any part of the
wire of the coil A provided that the upward movement of the core shunted out a
continually increasing section of the wire of the coil A. I have also shown an
angle between the conducting plates and the spring D greater than is necessary in
practice.
The method of supporting the carbon holder is also new in this lamp and it is
operated directly by the movement of the axial magnet whose movement is
controlled by the regulating device heretofore described. The carbon holder in
this apparatus is held by two eccentric or cam friction clutches which are so
contrived that when the core is elevated from a rest stop the cams act against the
carbon holder and raise it or hold it in position, while when the core is dropped
the cams come in contact with the rest stop referred to and the carbon holder is
released, thereby allowing the reestablishment or shortening of the arc. Attached
to the lower end of the carbon holder are two vibratable lifting links k, pivoted
to the carbon holder at l. and to vibrating rods m. at n. At the opposite ends of
the rods m from the pivots n, are attached two cams p, p. These cams are fixed
to the ends of the rods m. which turn at right angles, and are supported in a
frame as shewn rectangular in configuration which is marked r. The cams are so
attached to the rods m. that when the ends of the rods m which are attached to
the links, are depressed, the surfaces of the cams are withdrawn from the carbon
holder, but when the link ends of the rods m are raised the cam surfaces are
forced together and against the carbon holder c. The angles of the link m, to the
frame r, therefore determines the grip of the cams. The operation of the apparatus
will be readily understood from the Drawing.
Supposing the apparatus to be in the condition shown and the current to pass
through the coil, thereby tending to raise the axial magnet B. By this movement
of the axial magnet, the links k will be raised thereby lifting the free or link ends
of the rods m, and causing the cams p to engage with and lift the carbon holder C.
If however the current through the helix a, should be interrupted or from any
other cause the axial magnet B should drop, the frame r, will come in contact with
the adjustable screws v, and will thereby be raised, so that the rods m, will form a
different angle with the frame thereby the cam surfaces of the cams p, will be
withdrawn from contact with the carbon holder and the carbon holder allowed to
drop, thus reestablishing the circuit or shortening the arc as the case may be.
It is plain that the mechanical arrangement might be varied in many ways
without altering the principle of the invention which consists in shunting out
a part of the attracting coil of a regulator lamp by means of apparatus controlled
by the upward movement of the core.
In some cases I prefer to dispense with the axial coil in which case I use the
following improvement in electric lamps or regulators, by means of which the
hollow coil and axial magnet are dispensed with, and an ordinary U magnet of a
peculiar shape having a fixed core substituted therefor. In the improved lamp
the vertical movement of the carbon is accomplished by means of an armature
which is laterally attracted toward a fixed magnet, said armature being itself
preferably polarized, and made of opposite polarity to that of the attracting pole
of the magnet.
The invention will be readily understood from the accompanying Drawings in
which Figure 7 represents an elevation, and Figure 8 a plan view. Similar letters
refer to similar parts. The whole details of the lamp are not given but merely
the working parts of the improvement. A represents the frame of the lamp
suitably supported and arranged, B the carbon holder. C. D. coils of a U magnet,
the poles being turned toward each other as shown. The rear ends are connected
by the yoke F, which makes a magnetic connection between the cores of the coils

page_text: C. D thereby increasing the attractive force. The coils C. D. as usual, are so
wound as to produce opposite polarities in their cores. Attached to the core of the
spool C, is the vibrating armature G which is arranged to lift the carbon holder.
This armature is pivoted to the core of the coil C, and magnetically connected
therewith. It surrounds the carbon holder B where it is enlarged into a ring as
shewn at H. The inner end of the core of the coil D is preferably curved so as
to correspond with the arc swept by the free end of G as it is elevated, and the
said free end of G may be correspondingly curved as shewn in Figure 1. The
coil D and its core are made vertically adjustable in the support by means of the
screw L thereby determining the length of the arc of the lamp. The coil D is
surrounded by the auxiliary or differential coil E which may be used when required
in the well known way. The clutch of the carbon holder is of the form heretofore
described by me in connection with Figures 4. 5. and 6. The links K. K. are
attached to the ends of levers, which control cams bearing against the carbon
holder B, which cams are supported in a frame M. As the armature G is elevated,
the cams are turned in against the carbon holder, which therefore rises with the
armature while when the armature G drops the lever ends are dropped, the
eccentrics or cams thrown away from the carbon holder and the carbon holder falls.
The links K. K are pivotted opposite each other on a line passing through the
centre of the carbon holder B at right angles to the movement of the armature,
thereby giving an equal movement to both cams. The operation of this lamp will
be readily understood. As soon as the electric current flows through the coils
C. D. which are of course connected in circuit as usual, the end of the armature G
and the inner end of the core of the coil D will possess opposite polarities, and said
free end will consequently be immediately raised. As it is elevated the clutch
on the carbon holder is operated and the carbon holder is raised, establishing the
The length of this arc is determined by the adjusting screw L in the manner
previously described. The arc if extinguished is reestablished by the dropping
of the carbon holder B in the manner previously described. I do not limit
myself to the precise arrangement shown, as other modifications will readily
suggest themselves.
arc.
What I claim as the invention and desire to secure by Letters Patent is
First An armature for dynamo machines and motors, wound with a series of
superposed coils between the layers of which thin flat plates of magnetic material
are circumferentially placed in combination with an additional or field magnet, for
the purpose of producing a magnetic field by said field magnet, and concentrating
said induced magnetism in immediate proximity to the wire of the armature,
substantially as described.
Second. The combination of a circular or ring armature provided with a series of..
superposed wire coils and plates of magnetic material interposed between them,
with an independent field magnet for inducing a magnetic field in said armature
substantially as described.
Third An armature in which the coils of wire are separated circumferentially
and radially by thin plates of magnetic material laid between them.
Fourth. The combination in an electric lamp or regulator of an axial magnet its
moveable core, a secondary helix attached to and moving with said core, and a
magnetic clamp magnetically insulated from the same, the said clamp seizing the
carbon holder when attracted by the varying magnetism of the core, said
magnetism being occasioned by the resultant of the magnetism induced by the
external and the secondary coils, substantially as set forth.
Fifth. An electric lamp provided with an outer main helix, a central moveable
core, carrying a regulating helix, a moveable carbon holder, and a clutch consisting
of pivoted armature levers and rings controlled and regulated by the varying
magnetism of the core as shown and described.
Sixth. The combination in an electric regulator of a principal coil with a hollow
interior secondary or differential belix which rises and falls by the varying
magnetism of the main coil, and a carbon holder centrally located with reference

page_text: to the main and differential coils and passing through said differential coil
substantially as described.
Seventh. The combination in an electric lamp of a moveable core or armature,
an attracting magnetic coil and mechanism moving with the core or armature and
operating a shunting apparatus connecting with the coil to shunt out successive
sections of the coil A, and thus decrease the attractive effect of the coil as the core
or armature enters or approaches said coil, substantially as described.
Eighth The combination of the coil A the core B, the spring D, and the shunt
connection shown, for the purpose of reducing the magnetism in the coil A on the
movement of the core B, by shunting out successive sections of the coils
substantially as described.
Ninth. A carbon holder clutch for an electric lamp, which consists of two
links k. k. two horizontal levers r, r, connected to two cams p. p. said cams being
located at the opposite side of a carbon holder from their respective controlling
links k. k. the said cams being supported in frame m. resting upon the adjusting
screws v. v. substantially as described.
Tenth. The combination of a carbon holder, a core and an eccentric cam clutch
operated by the core, with a shunting apparatus connected with the main coil of
the electro-magnet for the purpose of decreasing the attractive effect of the coil on
the core as the latter enters said coil substantially as described.
Eleventh. An electric lamp regulator which consists of a carbon holder a
polarized armature pivoted at one end at one side of the carbon holder and crossing
the latter, a magnet adjacent to the free end of the armature for raising the same
and magnetically connected with the pivot of the armature for polarizing the same,
and a clutch connecting the armature and the carbon holder substantially as
described.
Twelfth. The combination in an electric lamp regulator of a carbon holder and
polarised armature pivoted so as to swing in a vertical plane, a coil on the opposite
side of the carbon holder and facing and adapted to raise the free end of the
armature, and a clutch for raising the carbon holder, substantially as described.
Thirteenth. The combination in an electric lamp regulator of a vertically moving
polarized armature, surrounding a carbon holder, said armature being pivoted so as
to swing in a vertical plane, and a magnet coil, past the pole of which said
armature swings, said coil surrounding a core which is magnetically connected with
the pivoted armature for the purpose of magnetizing the same, substantially as
described.
Fourteenth. The combination in an electric lamp regulator of the free extension
armature G, coils C to which said armature is pivoted, polarizing the same, the
stationary coil D adapted to attract the free end of said armature G, the clutch
and the carbon holder substantially as described.
Fifteenth. The combination of the carbon holder B, the vertically swinging
pivoted armature G, the coil C and the attracting magnet D, itself made vertically
adjustable, substantially as described.
In witness whereof I the said Sydney Pitt have hereunto set my hand and
seal this twenty first day of April in the year of our Lord One thousand
eight hundred and eighty three.