Improvements in Paddle Wheels for Propelling Vessels.
Year: 1893

page_text: Date of Application, 14th Apr., 1893
Complete Specification Left. 18th Dec., 1893-Accepted, 3rd Mar., 1894.
PROVISIONAL SPECIFICATION.
Improvements in Paddle Wheels for Propelling Vessels.
t; GEORGE AUGUSTUS HAIG, of Pen Ithon, in the County of Radnorshire,
Gentleman, do hereby declare the nature of this invention to be as follows:-
My invention relates to paddle wheels for propelling vessels.
According to my invention all the paddles or floats are kept perpendicular or
nearly perpendicular all through the revolution of the wheel, and the whole wheel
is adapted to be mounted in a box inside the ship, which box is or may be filled with
compressed air to prevent the water rising beyond the proper height for the effective
working of the paddles as propellers. The wheel consists of two separate discs (or
radial wheels) each revolving with its own separate shaft, but one shaft is placed
above or out of line with the other at a distance proportioned to the depth of the
paddles, and the inner and overhanging ends of the two shafts are coupled together
by cranks on the ends of each inside the wheel and a connecting rod between them.
Then each paddle which stretches horizontally and perpendicularly between the
two discs or wheels is mounted at each end on a pin in each disc; which pins are
fixed firmly into the disc while the paddle is free to turn on them, or the pin may
be fixed in the paddle and free to turn in the disc as the wheel is moved round.
The paddles do turn round on the pins as the wheel is moved round and the effect
is to keep the paddles always in a perpendicular position. They enter the water in
a perpendicular position and they come out of the water in a perpendicular position
and remain perpendicular all the time they are moving through the water. The
number of paddles depends on the diameter of the wheel. Now I consider this to
be a very suitable wheel for working below the surface of the water in airtight
casings filled with compressed air, and by so placing it I am able to get an engine
on each side of it and to make it a strong and substantial paddle wheel put in a
position inside the hull of the vessel and therefore wholly protected from the blow
of the waves, while by coupling the two shafts together by cranks and a connecting
rod, and with an engine acting separately on each separate shaft. I can get a very
strong support on both sides so that it will be found to be a very efficient
propelling wheel.
The essential features of my invention are firstly, the putting of a crank on the
inside overhanging end of each shaft and the coupling of them together by a
connecting rod which makes it into a firm wheel and prevents the straining of the
paddles which would otherwise take place every time it started or stopped.
Secondly, the working of the wheel from both sides instead of one side only as
heretofore, by which I am able to get a much firmer wheel, well supported.
Thirdly, the placing of it inside the hull of the vessel instead of on the outside,
so that it is protected from the waves.
Dated this 14th day of April 1893.

page_text: .
COMPLETE SPECIFICATION.
Improvements in Paddle Wheels for Propelling Vessels.
I, GEORGE AUGUSTUS HAIG, of Pen Ithon, in the County of Radnor, Justice
of the Peace for said county, and of No. 7, Argyle Street, London, W., Merchant,
and of No. 236, Fulham Road, London, S.W., Manufacturer, 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 :-
.
My invention consists in a new kind of paddle wheel for propelling ships, and in
which the paddles are always kept as nearly perpendicular as the rolling and
pitching of the vessel will allow.
The wheel consists of two discs (or they may be radial wheels) each of which
stands and revolves perpendicularly and is mounted on and fixed to a horizontal
shaft properly supported and intended to be worked by a steam engine or other
motive power acting on a crank, and the other end of the shaft will project through
the disc rather less than half the breadth of the proposed paddle wheel, and is also
finished off with a crank. Each shaft and disc is a fac-simile of the other except
that the steam engine cranks are at right angles to each other so that if the two
shafts were laid in the same straight line, the two discs would revolve exactly
opposite to each other and perfectly parallel. But to make my peculiar wheel, one
shaft with its disc must. (as pointed out above) be raised to a higher level so that
while both shafts are still horizontal and while the centres of each are still in the
same perpendicular plane, the horizontal plane in which the centre of the raised
shaft now lies will be some distance higher than it was before, and that distance
will be less than the depth of the paddles intended to be placed between the two
parallel discs which are to form the sides of the wheel. This distance will vary in
larger and smaller wheels and may vary as the maker of the wheel pleases, but (as
at présent advised) with 21 foot wheels I propose to make it fifteen inches, and it
is this difference of centre which makes my paddles maintain the perpendicular
position. Now the shaft of each disc projects inside the wheel rather less than half
way and finishes off with a short crank, and these two internal cranks I connect
together by a connecting rod which will force the discs and their shafts and the
engines which drive them to move synchronously together, and so prevent all
twisting strain on the paddles. This arrangement of cranks and a connecting rod
inside the wheel is an essential feature of my invention and is one of the chief
things which I claim, because by it the wheel is made a strong, useful, and effective
paddle wheel for the propulsion of vessels, while without this internal connection if
the one engine went faster than the other the wheel might be twisted, strained, and
broken. Now those two discs (or they may be radial wheels,) form the sides of my
paddle wheel, and I have only to put paddles between with suitable connections to
complete it. But as the two discs move on different centres those paddles must be
connected with the discs by a pin at each end, and the distance between the centres
of those two pins must be exactly the same as the distance between the centres of
the two shafts with which the discs revolve. These pins must be fast in the discs
and loose in the paddle, or loose in the discs and fast in the paddle (either way will
work) and then the wheel is complete and able to move round freely, provided the
depth of the paddles is such that when passing under and over at each sides (see
the sketch, Fig. 1) there is ample room for them to pass clear, and the number of
paddles may be whatever the maker of the wheel prefers; but six, twelve, eighteen,
twenty-four, thirty-six will be found to be convenient numbers. That is my wheel,
but this wheel I mount inside an air-tight paddle-box filled with compressed air as.I
consider the upper part of the wheel working in air will considerably lighten the strain
upon the engines which drive it, nevertheless if the paddle boxes were full of water,
which might happen by an accident, the wheel would still work and propel the
vessel although at a greatly diminished speed. When the casings are filled with

page_text: 1
'compressed air as they will always be for economical working, an air pump or
pumps must be provided pumping direct into the casing or into a reservoir at a
higher pressure which will have proper connections to each paddle box or casing
for supplying accidental escape of air.
The annexed figures illustrate what I have explained in writing above, but they
are merely diagrams (line drawings) drawn to show the relative positions of the
parts and do not profess to show the actual shape or thickness or distribution of the
material nor the mode of connection, because each maker will use such materials
and size and weight as he chooses, and will fashion it to his own fancy but so as to
produce a paddle wheel in accordance with the description above, and as further
explained in the following diagrammatic sketches and always suited to do the work
it is intended for.
(
3)
Fig. 1 is a diagrammatic sketch, (the casing being in section) of one wheel
(assumed to be for illustration) 21 feet diameter between the centres of the pins . a.
on which the paddles P. P. move, and with paddles ten feet long and two and a half
feet deep. The wheel is supposed to be the centre wheel of a long string of wheels
in the centre of a ship with the paddles projecting through the first bottom A and
working into the water in a channel C formed below the first bottom A, the base of
which is the second bottom B.
The diagram Fig. 2 illustrates the same wheel in a cross section through the
centre of the wheel at right angles to Fig. 1, and it shows the top and bottom
paddles P P (one in air and the other in water) with their respective pins x. x. ou
which they are free to move, also the two discs D D₁ parallel and perpendicular
with lines d d to show how they may be strengthened and fixed firmly to their
respective shafts S S¹; it also shows the positions of the shafts S S¹ one above the
other with the cranks E E' on the overhanging end of each shaft S S' inside the
wheel and a connecting rod R between the two cranks E E' which ties the two
shafts S S together and obliges the whole to move synchronously and without
which the wheel would be useless.
Figs. 3 and 4 show on an enlarged scale two different forms of the two ends of a
paddle P showing its knife-edged shape and the position of the pins . . which
enable the paddle P to move and maintain its perpendicular position at all times
(and in my opinion the paddle with one side flat is the better shape) because the
distance between the centres of those paddle pins a. a. is exactly the same as
the distance between the crank pins e.e of the cranks E E' inside the wheel or
the length of the connecting rod R between its centres. I prefer to make the
paddles P hollow, with holes so that they will take up water which in the upward
part of the revolution will drip upon the internal cranks E E' and connecting rod
brasses and keep the working parts cool.
Those diagrams show plainly that when such a wheel is made to revolve the
paddles will always maintain their perpendicular position and this perpendicular
position I consider is quite necessary for the economical working of a paddle wheel
in propelling a ship when it is worked in the best possible position, namely, in the
centre of the vessel with its paddles projecting into the still water under the ship's
bottom or first bottom.
A paddle pressing against the water in that position uses the water as a fulcrum
at the end of a lever, the other end of which is attached to the propelling engine,
and is employed in pushing the ship forward overhead-the ship moves forward, the
paddle does not move backward-in fact when the ship is up to her speed the
paddle in my wheel only has a downward and then an upward motion because it
does not slip. Its motion is downward in the same perpendicular plane in which it
entered the water until the centre of the wheel overhead passes over it; then
the motion is upward until it rises out of the water at the same spot where it
entered.
Now in respect of the propulsion of ships by paddle wheels, I hold that it is a
great waste of power to try to propel ships at a high speed if the area of the
paddle surface in effective operation at the same time is less than the area of the

page_text: submerged midship cross section of the ship (it has always been less heretofore)
because the wheels must of necessity slip if the engines are powerful enough and
the paddle area too small, and my reason for inventing and patenting the wheel is
that I consider it to be necessary for high speed and economic working of paddle wheel
steamers that the area of effective paddle surface should always exceed the area
of the greatest cross section of the ship by a figure sufficient to overcome the skin
friction and an extra margin for varying obstructions such as the blow of the waves
and head winds. In my paddle wheel it is (when the ship is in motion) almost
impossible for the paddle to slip through the deep water it works in as the water
could only slip over the top or bottom of the paddle, but if the area of paddles
submerged and effective exceeds very much the area submerged of the cross section
of the ship say by 20 or 30 or 40 per cent., there could not possibly be any slip
even with the most violent head wind, and therefore the ship must move forward at
the same rate as the paddle wheels move over the water, that is, at the same rate
as the circumference of the paddle wheel. My wheel as sketched above has a
rolling diameter of 21 feet or a rolling circle of say 22-yards, and if it is made to
revolve 97 times in a minute (allowing for the ratio of chord to are of immersed
segment) the ship will have passed over 1760 yards in one minute or sixty miles
an hour.
Undoubtedly a ship to move at such a speed against a head wind must be very
strongly built and furnished with very strong wheels and very powerful engines,
and must carry a very much larger supply of coal than slower ships, but if it can
go two and a half times as fast as any vessel now afloat, two of my suggested
express steamers would do the work which it now takes five steamers to do, and
nearly all the working expenses except coal will be reduced very nearly in the
ratio 5 to 2.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. Cutting short the overhanging ends of the two shafts inside the wheel and
putting a crank on each of them and coupling these two cranks together by a
connecting rod which constrains both discs or sides of the wheel to move
synchronously together when driven either from one side or both sides of the
. wheel.
2. The hereinabove described construction of paddle wheels for propelling
vessels which consists essentially in the following combination and arrangement,
viz. a pair of discs or radial wheels such as D D each fixed upon and carried by
a separate shaft independently rotated, the said shafts being out of line with one
another but in the same perpendicular plane, cranks E E¹ fixed on the two adjacent
inuer and overhung ends of said shafts (inside the wheel), a connecting rod, such
as R coupling together the said cranks E E', and paddles preferably of the knife-
edged form illustrated mounted between and working on pins engaging the two
said side discs, whereby a strong wheel is produced in which the paddles are always
maintained in practically perpendicular positions and straining of the parts is
prevented, and whereby also a wheel is produced which is adapted to be driven
from both sides (instead of from one only as heretofore) all substantially as and
for the purposes above set forth.
Dated this 16th day of December 1893.
GEORGE AUGUSTUS HAIG.