IMPROVEMENTS IN ELECTRIC GENERATORS AND IN WORKING THEM BY FLUID PRESSURE
Year: 1884

page_text: I The Honourable CHARLES ALGERNON PARSONS, of Victoria Works, Gateshead
on Tyne in the County of Durham, a member of the firm of Clarke, Chapman
and Co Engineers do hereby declare the nature of said invention for "IMPROVEMENTS
IN ELECTRIC GENERATORS AND IN WORKING THEM BY FLUID PRESSURE" to be as
follows:-
'
My invention is designed to produce an electric generator which may be driven
at a very high rate of speed, several or many times as fast as such machines are
now driven, the object being to obtain a large current or a high electromotive
force, or both, from a small machine, and also to obtain an increased efficiency.
In a generator according to my invention, as the magnetic field is small, it will be
proportionately intense, while, as the armature need have but few convolutions, its
internal resistance will be much less than usual.
According to my invention the generator is driven by a compound motor, or
combination of motors, of the turbine type, referred to in the specification of my
application for Letters Patent No 6735 bearing even date herewith,-in which the
actuating fluid operates between fixed and moving vanes or blades, the arrange-
ment being such that the same actuating fluid operates in a successive manner,
undergoing expansion and falling in pressure in each motor, or successive portion
of the compound motor, until it leaves the last at a velocity not greatly exceeding
that which is practically attainable by the motor itself, although greatly above
that practicable with a motor having oscillating or reciprocating parts. By this
arrangement each motor or successive portion of the compound motor utilizes a
portion of the energy of the fluid, and thus, instead of the greater part being
wasted, as heretofore, it is successively drawn upon until a comparatively high
efficiency is obtained.
On the shaft of the generator proper, or upon a shaft, firmly coupled thereto, is
provided a body which may conveniently be formed as a series of cylinders having
vanes on their peripheries set to an angle of about 45°. These cylinders are in three
sets, the largest in diameter of each set is near the inlet for actuating fluid, next to
each of these is a smaller cylinder, next to it a smaller one, and so on. Conveniently
the cylinders may be built up of a series of discs or rings. Between each two sets

page_text: of vanes or blades on the cylinder, carried by the shaft is arranged a set of vanes or
blades set at an opposite angle of about 45° and fixed to the interior of a hollow
cylinder or casing surrounding and enclosing the first named cylinders.
The direction of motion of the actuating fluid is in the direction of the axis of
the cylinders. Thus it will be understood when all the parts are put together the
fixed portion forms a hollow cylinder with projecting rings of blades and the moving
portion a solid cylinder also with projecting rings of blades. The exhaust takes
place at both ends. The bearings are made slightly elastic with frictional resistance
to their motion. To ensure efficient lubrication suitable means are employed to force
lubricant to the parts to be lubricated.
To prevent the machine becoming unduly heated by the intense currents which
are developed I introdúce suitable fluid such, as oil or water into the interior of the
armature or into a casing into which the heat developed in the armature, flows, and
I maintain a circulation of such cooling fluid, and carry off the heat, which may be
dissipated in any convenient way.
It is often advantageous to form the commutator complete in itself, so that it
can be removed bodily for returning or when worn out. To this end I attach the
copper strips with suitable insulation to a metal cylinder which can be slipped on
and off the shaft of the generator. This commutator can likewise be cooled by
causing the lubricant to pass down the shaft and thereby abstract the heat by
conduction from the shaft and the metal cylinder.
In order to assist the cooling of the wire and also to retain it in its place at high
speeds I sometimes use strips of thin metal cut transversely by numerous slits and
fastened into dovetailed slots in the iron core of the armature by caulking in with
some material such as soft brass wire or other suitable substance.
Dated this 23rd day of April 1884 -

page_text: I, The. Honourable CHARLES ALGERNON PARSONS, of Victoria Works, Gates-
head-on-Tyne, in the County of Durham, a member of the firm of Clarke,
Chapman and Co Engineer's, do hereby declare the nature of my said invention for
"IMPROVEMENTS IN ELECTRIC GENERATORS AND IN WORKING THEM BY FLUID
PRESSURE" and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
My invention is designed to produce an electric generator which may be driven
at a very high rate of speed, several or many times as fast as such machines are
now driven, the object being to obtain a large current or a high electro-motive
force, or both, from a small machine, and also to obtain greater steadiness in the
current and an increased efficiency.
In a generator according to my invention as the magnetic field is small, it will
be proportionately intense; while, as the armature need have but few convolutions
its internal resistance, will be much less than usual.
According to my invention the generator is driven by a compound motor, or
combination of motors, of the turbine type;. referred to in the specification of my
application for Letters Patent No 6735 bearing even date with the application to
which my present specification relates, in which the actuating fluid operates between
fixed and moving vanes or blades, the arrangement being such that the same
actuating fluid operates in a successive manner undergoing expansion and falling in
pressure in each motor or successive portion of the improved motor until it leaves
the last at a velocity not greatly exceeding that which is practically attainable by
the motor itself although greatly above that practicable with a motor having
oscillating or reeiprocating parts.
By this arrangement each motor or successive portion of the compound motor
utilizes a portion of the energy of the fluid, and thus, instead of the greater pärt
being wasted, as heretofore, it is successively drawn upon until à comparatively
high efficiency is obtained.
On the shaft of the generator proper or upon a shaft firmly coupled thereto, is
provided a body which may conveniently be forined as a series of cylinders having
vanes on their peripheries set to an angle of about 45°. These cylinders are in
three sets, the largest in diameter of each set is near the inlet for actuating fluid;
next to each of these is a smaller cylinder, next to it a smaller one, and so on.
Conveniently the cylinders may be built up of a series of discs or rings.
Between each two sets of vanes or blades on the cylinder carried by the shaft is
arranged a set of vanes or blades set at an opposite angle of about 45° and fixed
to the interior of a hollow cylinder or casing surrounding and enclosing the first
named cylinders.
The direction of motion of the actuating fluid, is in the direction of the axis of
the cylinders. Thus it will be understood when all the parts are put together the
fixed portion forms a hollow cylinder with projecting rings of blades and the imoving
portion a solid cylinder also with projecting rings of blades. The exhaust takes
place at both ends. The bearings are made slightly elastic with frictional
resistance to their motion. To ensure efficient lubrication suitable means are
employed to force lubricant to the parts to be lubricated.
To prevent the machine becoming unduly heated by the intense currents which
are developed I introduce suitable fluid such as oil or water into the interior
of the armature or into a casing into which the heat developed in the armature
flows and I maintain à circulation of such cooling fluid, and carry off the heat which
may be dissipated in any convenient way.
It is often advantageous to form the commutator complete in itself, so that it can"
be removed bodily for re-turning or when worn out. To this end I attach the
1

page_text: copper strips with suitable insulation to a metal cylinder which can be slipped on
and off the shaft of the generator.
This commutator can likewise be cooled by causing the lubricant to pass down
the shaft and thereby abstract the heat by conduction from the shaft and the
metal cylinder.
In constructing and working electric generators according to my present invention
1 find it advantageous to adopt certain improvements or features hereinafter
referred to which constitute parts of an invention for which I have made applica-
tion for Letters Patent under date the 7th day of November 1884 N° 14723 and
therefore it will be understood that whilst in order to explain fully what I conceive
to be the best manner of carrying my present invention into practical effect I have
decmed it advisable to refer to the improvements or features in question in the
present specification yet I do not by so doing intend to lay any claim to any of the
said improvements or features as forming parts of my present invention. Thus,
the improved form of armature of the drum or Siemens' type hereinafter described
and shewn; also the improved commutator formed of several rings of segments
retained in position around a central bush by interlocking steel rings as hereinafter
described; also the mode and means hereinafter described and shewn for
regulating the supply of actuating fluid to the motor by means of apparatus
controlled by the current itself acting through a magnet or solenoid; are severally
described in my above mentioned specification N° 14723 A.D. 1884 for the
reason already stated and are not now claimed as forming parts of my present
invention.
Referring to the accompanying two sheets of drawings Figs 1 and 2 shew in
elevation and plan a double apparatus according to my invention, each half com-
prising an electric generator and a motor. Fig 3 is a vertical longitudinal section
of one apparatus. Fig 4 is a section to an enlarged scale through one of the
bearings of the central shaft. Fig 5 is a longitudinal section through the
armature and commutator of the generator. Fig 6 is a similar view shewing
modified method of arranging the conductors. Fig 7 is an end view of the same
partly in section.
'
a
In Figs 1. and 2 a. a are the pole pieces of the field magnets which are excited
by the current flowing in the coils e. e.
The armature is not visible in Figs 1 and 2, but is to be seen in Fig 3. It is
mounted upon a shaft which runs through the three bearings d. d' d². Upon the
same shaft which may be in one piece, or two or more pieces coupled together
the moving portion of the motor m is carried. g. g are guards of non-magnetic
imetal which protect the armature, and also carry the magnets. b. b. b are the
- brushes carried on the holder g and pressing on the commutator c; by preference
these brushes are made of fine brass wire. The motor which is shewn in section
in Fig 3, is formed of two compound or built up cylinders mounted on the
cylindrical enlargements A. A. of the centre shaft S so as to rotate therewith;
B. B¹ B² B. B¹ B2 are sets of blades on each cylinder, C is a casing in two parts
bolted together as indicated in Figs 1 and 2. F. F¹ F2 F. F1 F2 are blades nixed
within the casing C these blades being inclined in opposite direction to the blades
on the rotating cylinders. In the arrangement as drawn each set of moving blades
is represented as being formed out of solid metal on the circumference of a brass or
steel disc or ring, a number of these discs or rings being threaded on the parts A. A
of the shaft S which is formed with a collar or projection S¹ between A. and A.
At each end is a disc or ring (with blades) that fits on a smaller portion A2 of the
shaft. The shaft is provided with nuts or screwed collars S². S2 at the respective
ends by which the set of discs or rings with blades forming each cylinder is held in
place against S¹. The fixed blades are represented as being formed by cutting each
row internally on a ring which is afterwards cut diametrically into two parts one
of which is joined to the top half of the casing C (by a small longitudinal feather
mentioned below) and the other to the lower portion of that casing. It will be
seen that the fixed portion forms a hollow cylinder with projecting rings of blades.

page_text: and the moving portion a built-up solid or compound cylinder also with projecting
rings of blades.
The rings with which the blades are formed are prevented from turning, by
feathers, those for the fixed rings being sunk in the top half of the hollow cylinder
and being separated by an angle of about 140° and those for the other rings being.
sunk in the shaft with which they revolve. It is to be noted that although I have.
shown straight blades cut from the solid because such blades present facilities of,
manufacture and by means of dies can be readily set to any desired shape; yet
other forms of blades may be employed..
In some cases it may be found convenient to make the blades of sheet metal and
to secure them in suitable grooves or recesses in the rings.
In this way the blades may be made thinner and they may be accurately formed
either before or after insertion in the rings.
I will assume that steam is the actuating fluid employed. It enters the motor at
its centre and travels towards each end of the motor between the respective moving
cylinders and fixed casing C acting in its passage upon the moving blades and being
deflected and guided by the fixed blades until it reaches the exhaust passages which.
are carried underneath the motor to the centre. The blades where the steam
enters are comparatively shallow but towards the respective ends of the motor they
increase in depth by sets, B₁ being deeper than B and B² deeper than B¹.
Where the steam enters the blades are set at a greater angle than where
it exhausts. Hence as the steam pressure decreases it meets with sets of blades
of increased area and pitch the increase being so calculated that the velocity of the:
steam shall be suitable to that set of blades between which it has to pass.
The bearings of the dynamo and its motor have a certain amount of elasticity or
play combined with a frictional resistance to their motion and thus the moving
part will be enabled to rotate around the centre of gravity instead of the geo-
metrical centre, if the two be nearly coincident, and the vibration will be damped
or modified. To this end they are constructed as shewn in Fig 3 and to a larger
scale in Fig 4.
I is a light bush outside of which are placed metal rings or washers K. K¹. The.
alternate washers K are slightly larger than the washers K' so that the alternate"
washers K fit the casing but not the bush, and the washers K' fit the central bush
but not the casing. L is a spiral spring and M is a nut. By these the rings or
washers K. K' are pressed tightly together. Thus the bush is capable of a slight
lateral movement, but this movement resisted and controlled by the rings or
washers and their mutual friction. The amount of liberty given to the rings or
washers may be, say, one hundredth part of an inch diametrically, but it may be
more or less according to circumstances as may be found desirable in practice.
The lubrication of the bearings and the cooling of the armature and commutator
are carried out by means of a screw pump 3 at the end of the central axis and of
the pipes r,,2. The oil from the reservoir is forced by the pump through the
bearing & and the pipe r to the bearing d² some of the oil goes to lubricate the
bearing, but the greater part flows through the hollow spindle of the armature
(Figs 5 and 6), cooling the armature and commutator, and then lubricating the
bearing d¹..
The oil, after performing its office, returns by the pipes 1, 2, to the central
junction piece x from which it is again drawn through the pipe 2 to the reservoir r¹.
The raising of the oil is not effected by the suction of the screw pump, but by a
fan also mounted on the central axis which is connected by a tube to the stand
pipe, and constantly maintains a partial vacuum therein. The power of the fan
is not sufficient to draw the lubricant over the head of the stand pipe.
Fig 5 is a longitudinal' section of an armature suitable for use in a generator
revolving at a high rate of speed. Upon a hollow shaft d* there are arranged a
series of tightly fitting iron discs or washers a*, a*, insulated from each other,
preferably by paper. At each end of the series of iron washers is a washer or
disc c² of insulating material, Beyond each of the washers c² is a second insulating,

page_text: washer c; and after tliese there comes another series of metal washers, preferably of
brass, the arrangement being concluded at each end by an insulating washer c¹
forced up by a nut,
The iron washers, which form the core of the armature are pierced at equal
angular distances with holes or channels in which the conductors f* f* are placed.
Each conductor is laid in separately, and is coupled to the corresponding one at the
other side of the armature in the following way-Every alternate conductor is
bent down along a groove in the washer c, and is then carried round the cylinder
at an angle of about 45 degrees with the axis as shewn in dotted lines, and is
finally threaded through a hole in the outer flange or washer. When the one half
of the conductors have been thus treated they are bound round with insulating
tape, and, the remaining half are similarly arranged, except that they are bent in
the opposite direction. The ends f1f2 are united in couples, and at the commutator
end every alternate one of the wires is left projecting and fits into a suitable
recess or hole in one of the commutator segments 1. 7. The coupling of the
conductors. ff is preferably effected by fine wire or copper rings, and is so
arranged that when completed the whole of the wires form a continuous circuit.
In the drawing there are 20 convolutions and there are 10 segments in' the
commutator, which are connected to each alternate coil.
In Fig 6 the wires are shewn differently arranged at the end furthest froin the
commutator. Where instead of the conductor being divided and coupled to the
next in the manner described above it is bent and passed back through the outer
ring of lioles.
To retain the wire in position I prefer to use pianoforte steel wire bound on
tightly over suitable insulation.
In order to resist the great centrifugal force the commutator is formed of several
rings of gun-metal segments l, l.retained in position on the bush n by the steel
rings m*m* and the nut o. The segments are insulated from each other, and
from the rings m* m*, preferably by asbestos millboard.
·
The regulating apparatus is shewn in Figs 1 and 2 and to a large scale in Figs 8
and 9. It is mounted upon the top of the field magnets, by which it is operated,
and is connected by the pipe v to the diaphragm t (Figs 1 and 10). A bar of soft
iron i. (Figs 2 and 9) is pivotted on a vertical spindle j. j which also carries a
finger or pointer k, ending in a valve or guard which covers more or less the inlet
to the pipe v The polarity of the magnet tends to place the bar i parallel to the
lines of force, and this tendency is resisted by the spring * which is attached at
one end to the spindle and at the other to an adjustable bush o* which can be
rotated and fixed as desired to vary the tension of the spring. When the magnets
are shunt wound and the iron is far from saturation the intensity of the
magnetisation will vary as the electro-motive force at the terminals, and when
they are series wound it will vary as the current. Thus a self-regulating machine,
either for constant electro-motive force or constant current will be produced. The
pipe connects the air inlet on the magnetic regulator, with the space enclosed
between the flexible diaphragms tt (Fig 10) These diaphragms are stiffened by
metal discs in the usual way, and the outer one is mounted on a spindle o¹, which
is impelled outwards by the spiral spring p. The space between the diaphragmns is
in connexion, by the passages s, s¹, with the exhaust fan 26, which raises the
lubricant and every movement of the diaphragms consequent on the variations of
pressure due to the varying speed of the motor which drives the fan, is transmitted
by the spindle o¹ to the valve f which governs the supply of actuating fluid to the
motor: So far the arrangement shewn in Fig 10 is similar to that already described
in the specification No 6735 mentioned above.
In case the regulator should cease to act efficiently either from accident to itself,
or to the dynamo or to the external circuit, excessive speed of the motor is
prevented by the action of the piston x*: This is normally kept in the position
shown in the drawing, by the spring w, w, and in that attitude it partially closes
the passages between the diaphragm and the pump. The rear end of the piston is'

page_text: enlarged at x, and stands in a cylinder y. One end of this cylinder is exposed to
the atmosphere through the holes . 2, and the other the suction of fan through the
hole c*. Should the fan attain a dangerous velocity the reduction of pressure in
the cylinder y causes the piston x* to be forced forwards against the opposition of
the spring, which is adjusted to permit of this, and a clear passage is left between
the pump and the pipe v. The diaphragms are then exhausted and the supply
valve to the motor closed, and this independently of the magnetic regulator. In my
provisional specification I proposed in order to assist the cooling of the wire of the
dynamo and also to retain it in its place at high speeds sometimes to use strips of
thin metal cut transversely by numerous slits and fastened into dovetailed slots in
the iron core of the armature by caulking in with some material such as soft brass
wire or other suitable substance, but I do not now consider such arrangement so
advantageous as I then supposed it to be and I therefore lay no claim to it.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. Driving an electric generator by the action of motive fluid against projecting
blades mounted upon the shaft or axis of such generator so as to rotate within a
hollow cylinder or cylinders having projecting blades, the motive fluid being caused
to travel in directions parallel or approximately parallel to the shaft or axis that
carries the moving blades and moving parts of the generator substantially as
described.
2. Supporting the shaft or axis of the electric generator in bearings constructed
to allow of slight lateral play resisted by frictional and elastic pressure, substantially
in the manner hereinabove described.
3. Feeding lubricant to the bearings of the electric generator by a screw or
centrifugal pump, mounted on the axis of the generator, and acting in conjunction
with a fan (also mounted on the same axis) for raising the lubricant to the pump
substantially as described.
4. The use for carrying away heat generated in the armature of the electric
generator of the hollow axis affording a passage for lubricating or other liquid in
combination with the screw pump which forces the said liquid through the axis
and the fan which raises the liquid to the pump substantially as described.
5. Forming the commutator of the electric generator complete in itself, so that it
can be removed bodily when required substantially as described.
6. In a machine for generating electricity the combination of a motor constructed
with a rotary part having projecting vanes or blades mounted on a shaft or axis
supported in bearings constructed to allow of slight lateral play resisted by
frictional and clastic pressure a generator having its moving part mounted on the
same shaft or axis and means substantially such as described and shewn for forcing
lubricant to the bearings and cooling the moving parts of the generator as above
set forth.