IMPROVEMENTS IN DYNAMO-ELECTRIC AND ELECTRO-DYNAMIC MACHINES
Year: 1882

page_text: LETTERS PATENT to Joseph Devonport Finney Andrews, of Sauchiehall
Street, in the County of Lanarkshire, for an Invention of "IMPROVEMENTS IN
DYNAMO-ELECTRIC AND ELECTRO-DYNAMIC MACHINES."
PROVISIONAL SPECIFICATION left by the said Joseph Devonport Finney
Andrews at the Office of the Commissioners of Patents on the 3rd February
1882.
JOSEPH DEVONPORT FINNEY ANDREWS of Sauchiehall Street in the County of
Lanarkshire. "IMPROVEMENTS IN
DYNAMO-ELECTRIC AND ELECTRO-DYNAMIC
MACHINES."
My Invention relates to the construction and arrangement of dynamo-electric
machines whereby mechanical power is converted into electricity, and of electro-
dynamic machines by which electricity is converted into mechanical power, and to
appliances for collecting and distributing the electricity in such machines and
for governing their motion. I construct the rotating armature in the following
manner. On a length of flexible iron rope I wind transversely a number of coils
of insulated wire. I wind the rope so coiled in a number of convolutions round a
barrel of wood or other non magnetic material, thus forming the coiled armature of
the machine, which revolves between two opposite magnetic fields each extending
over a considerable arc of the circumference. The wires of the several armature
coils may be connected to a commutator of any known kind. I prefer however to
fix side by side on the shaft of the armature a number of rings split like key rings
corresponding to the number of coils or groups of coils each ring being divided in
halves and all insulated from each other. I connect the two wires of each coil to
the two halves of one of the rings, and I arrange brushes to rub on the circum-
ference of all the rings. By suitably proportioning the width of the coils to the
diameter of the barrel on which the coiled rope is wound, each coil of one
convolution of the rope is made to enter and leave each field a little before the
coil on the next convolution, and the commutator ring for the former coil has its

page_text: division a corresponding amount in advance of the division of the ring for the
latter coil. Thus the brushes continuously collect or distribute the electric currents.
The coils may be connected in various ways to the rings so as to group them or
various numbers of them as may be desired either in series or in parallel circuits.
A machine of simple construction is of the following kind. An iron shaft having
at each end a cross-bar and on its middle a pulley is mounted to revolve within a
pair of stationary tubes on which are coiled insulated wires so that the shaft and
its cross bars constitute an electro-magnet. Around the coils on the tubes are
stationary electro-magnets presenting their poles so that the cross bars revolve in
front of them. The machine as above described is double, one half on each side of
the middle driving pulley, but either half might be removed without affecting the
action of the other half. On the framing is fixed a commutator consisting of
2 divided rings insulated from each other and connected respectively to the central
coils and to the coils of the electro-magnets, and on these rings rub brushes carried
by the revolving shaft. The framing is conveniently made as a single casting
having the tubes projecting from it to carry the central coils and the cores of the
electro-magnets also projecting from it. When the commutator used in a dynamo-
electric or electro-dynamic machine is of the usual construction consisting of plates
insulated from each other I add to the pair of diametrically opposite brushes
usually employed additional brushes rubbing on other points of the circumference
so as to collect or distribute the electricity while the revolving coils are entering
and leaving the magnetic fields. In like manner when the machine has several
sets of poles I employ two cominutator brushes for each pole. I also mount the
brushes whether there be one pair or more pairs than one so that they can be
turned more or less round relatively to the position of the field magnets, employing
this movement as means of governing the electrical production of a dynamo-
electric machine or the electrical power applied to work an electro-dynamic
machine. Or while the brushes remain stationary the commutator may be turned
more or less round on the shaft, or the brushes remaining stationary and the
commutator being fixed on the shaft, the armature may be turned more or less
round on the shaft relatively to the commutator. This arrangement for governing
may be carried out in various ways. According to one method I fix the armature
on the shaft and I fit the driving pulley and commutator loose on the shaft con-
necting them to the armature by a spring through which the driving power is
conveyed. When this is excessive the spring beconies so far strained as to turn
the commutator to a position on the shaft by which the power is lessened and
conversely. According to another method I connect the armature and cominutator
which are fixed on the shaft to the driving pulley through a differential coupling
which may be of the known sun and planet kind, the frame of the planet wheels
being strained by a spring and carrying the commutator brushes, so that according
as the spring is more or less strained by the driving strain conveyed through the
coupling, the brushes aro shifted more or less round so as to collect or distribute
more or less electricity. These methods of governing are obviously applicable
to dynamo-electric and electro-dynamic machines generally.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Joseph Devonport Finney Andrews in the Great Seal Patent
Office on the 3rd August 1882.
JOSEPH DEVONPORT FINNEY ANDREWS of Sauchiehall Street in the County of
Lanarkshire. "IMPROVEMENTS IN DYNAMO-ELECTRIC AND ELECTRO-DYNAMIC
MACHINES."
My Invention relates to the construction and arrangement of dynamo-electric
machines whereby mechanical power is converted into electricity, and of electro-
dynamic machines by which electricity is converted into mechanical power, and to
appliances for collecting and distributing the electricity in such machines and for
governing their motion. I construct the rotating armature in the following
manner. On a length of flexible iron rope I wind transversely a number of coils
of insulated wire. I wind the rope so coiled in a number of convolutions round a
barrel of wood or other non-magnetic material, thus forming the coiled armature
of the machine, which revolves between two opposite magnetic fields each
extending over a considerable arc of the circumference.
The wires of the several armature coils may be connected to a commutator of
any known kind. By suitably proportioning the width of the coils to the diameter
of the barrel on which the coiled rope is wound, each coil of one convolution of
the rope is made to enter and leave each field a little before the coil on the next
convolution, these coils being suitably connected to the commutator plates from
which the brushes collect the electric currents. The coils may be connected in
various ways to the commutator plates so as to group them or various numbers of
them as may be desired either in series or in parallel circuit. When the commu-
tator used in a dynamo-electric or electro-dynamic machine is of the usual con-
struction consisting of plates insulated from each other I add to the pair of
diametrically opposite brushes usually employed additional brushes rubbing on
other points of the circumference so as to collect or distribute the electricity while
the revolving coils are entering and leaving the magnetic fields. In like manner
when the machine has several sets of poles I employ two commutator brushes for
each pole. I also mount the brushes whether there be one pair or more pairs than
one so that they can be turned more or less round relatively to the position of the
field magnets, employing this movement as means of governing the electrical
production of a dynamo-electric machine or the electrical power applied to work an
electro-dynamic machine. Or, while the brushes remain stationary the commutator
may be turned more or less round on the shaft, or the brushes remaining stationary
and the commutator being fixed on the shaft, the armature may be turned more or
less round on the shaft relatively to the commutator. This arrangement for
governing may be carried out in various ways. According to one method I fix the
armature on the shaft and I fit the driving pulley and commutator loose on the
shaft connecting them to the armature by a spring through which the driving
power is conveyed. When this is excessive the spring becomes so far strained as
to turn the commutator to a position on the shaft by which the power is lessened
and conversely. According to another method I connect the armature and commu-
tator which are fixed on the shaft to the driving pulley through a differential
coupling which may be of the known sun and planet kind; the frame of the
planet wheels being strained by a spring and carrying the commutator brushes, so
that according as the spring is more or less strained by the driving strain conveyed
through the coupling, the brushes are shifted more or less round so as to collect or
distribute more or less electricity. These methods of governing are obviously
applicable to dynamo-electric, and electro-dynamic machines generally.

page_text: DESCRIPTION OF THE DRAWINGS.
Fig: 1 is a transverse section of a machine according to my Invention and
Fig: 2 is a longitudinal section thereof shewing the revolving armature in elevation.
This armature as above described consists of a non-magnetic barrel or core A fixed
on the driving-shaft B and having wound round it a number of convolutions of
iron wire rope C round which have been previously wound a number of coils D of
insulated conducting wire. Iron washers E may be interposed between the
successive coils, which as shewn in Fig: 2, follow each other in helical order so
that each enters and leaves the magnetic fields a little in advance of the next in
order. The magnetic fields consist of two masses of iron N and S wound length-
wise with insulated wire F and connected to each other by iron frames G. On
the shaft B is fixed the commutator H which may be of any known kind provided
with collecting brushes in the usual way, and having its insulated plates connected
to the coils D in any desired suitable order or grouping.
Fig 3 is a longitudinal section of the armature which is fitted free on the
shaft B but connected to it through a spring K that yields a little when excessivo
force is transmitted through it, and so shifts relatively to the commutator brushes
the times of passage of the successive armature coils through the magnetic fields,
that the force is reduced. Fig: 4 is a plan and Fig: 6 is a cross-section shewing
the method above described of automatically varying the position of the collecting
brushes L relatively to the plates of the commutator H according as more or less
force is transmitted through the shaft B. In this case the movement is transmitted
to or from a separate shaft M through a differential coupling of the sun and
planet kind consisting of bevil wheels NO, the wheels O being mounted on a
frame which carries the brushes L and is strained by springs P. As the driving
strain passes through the bevil gearing the brush frame is moved more or less in
opposition to the springs and the brushes are thus shifted more or less round
relatively to the commutator plates so as to give passage for less or more electricity.
It is obvious that the regulating arrangements described with reference to Figs: 3,
4, and 5 are applicable generally to dynamo-electric and electro-dynamic machines.
Having thus described the nature of the said Invention and in what manner tho
same is to be performed I claim in respect of dynamo-electric and electro-dynamic
machines:-
First. Constructing the revolving armature by winding on a non-magnetic core,
iron wire rope coiled with insulated conducting wire, substantially as herein
described.
Second. The construction and arrangement of machine, substantially as herein
described, with reference to Figs : 1 and 2.
Third. Driving the armature through a spring from the shaft which carries the
commutator, substantially as and for the purposes herein set forth with reference
to Fig: 3.
Fourth. Driving the armature and commutator through a differential coupling
having the brushes attached to a spring frame carrying the intermediate gear of
the coupling, substantially as and for the purposes described with reference to
Figs: 4 and 5.
In witness whereof I the said Joseph Devonport Finney Andrews have
hereunto set my hand and seal this First day of August in the year of
our Lord One thousand eight hundred and eighty two.
.
АППЕТРО