IMPROVEMENTS IN AND CONNECTED WITH SCREW PROPELLERS AND THEIR SHAFTS, AND IN PART APPLICABLE FOR GOVERNING OR CONTROLLING OR FOR MEASURING THE POWER TRANSMITTED BY OTHER ROTATING SHAFTS
Year: 1878

page_text: LETTERS PATENT to Howard Pullar, of Perth, in the County of Perth, North
Britain, Engineer for the Invention of "IMPROVEMENTS IN AND CONNECTED
WITH SCREW PROPELLERS AND THEIR SHAFTS, AND IN PART APPLICABLE FOR
GOVERNING OR CONTROLLING OR FOR MEASURING THE POWER TRANSMITTED
BY OTHER ROTATING SHAFTS."
aled the 19th November 1878, and dated the 31st May 1878.
PROVISIONAL SPECIFICATION left by the said Howard Pullar at the Office
of the Commissioners of Patents on the 31st May 1878.
HOWARD PULLAR, of Perth in the County of Perth, North Britain, Engineer
"IMPROVEMENTS IN AND CONNECTED WITH SCREW PROPELLERS AND THEIR SHAFTS,
AND IN PART APPLICABLE FOR GOVERNING OR CONTROLLING OR FOR MEASURING
THE POWER TRANSMITTED BY OTHER ROTATING SHAFTS."
This Invention comprises various improvements in and connected with screw
propellers and their shafts; and some of these improvements relate to the governing
or controlling of the motion of the shafts and are in p art applicablein the case of
other rotating shafts, and also for measuring the power transmitted by rotating
shafts.
It is an object of one part of the Invention to obtain improved constructions or
modes of combining the parts of non-feathering and of feathering screw propellers.
Other parts of the Invention relate to modes of feathering the blades automatically
and otherwise and to the apparatus for effecting the feathering operation; and the
Invention also comprises means or appliances for governing or controlling the
motive-power apparatus through the action of the strains to which the blades of the
propeller are individually subjected or of the strains to which the shaft is subjected,
or of both those strains. Several modifications, each consisting of a screw propeller
with the apparatus connected with it, become developed out of the various modes
ID 1 971

page_text: in which it is possible to combine the portions appertaining to the several parts of
the Invention as hereinbefore indicated.
In one arrangement of the improved propeller the blades are secured in their
sockets in the boss by means of steel or other rings encircling the shaft or on pins
parallel or oblique thereto, such rings being formed with projections which are
rivetted or otherwise fixed or jointed to the shanks of the blades; or the ring pieces
may be forged or otherwise formed on the shanks of the blades. This construction
is applicable to a rigid-bladed propeller the blade shank in that case filling the
socket in the boss, but in the present arrangement the blades are allowed a limited
movement in their sockets in a direction round the shaft or in a forward direction
or in oblique directions, and the blades bear by their shanks on piston buffers or
cushions held in cylinders or recesses formed for them in the boss such cylinders
containing water or other suitable liquid the pressure of which resists the strain to
which the blade is subjected when propelling. The several buffer cylinders com-
municate by branch pipes or passages with a bore or passage in the shaft, and at
the first or any convenient coupling or other part of the shaft inside the vessel this
bore communicates with a number of small hydraulic cylinders or barrels placed
round the shaft and having plungers fixed to or bearing against a sliding ring which
encircles the shaft and is acted on by a number of springs having their other ends
fixed to the shaft; and the sliding ring has formed on it a groove which acts inde-
pendently of the rotation of the shaft on a lever on a fixed centre. The lever is
connected to the throttle or cut-off valve of the engines and acts on it in accordance
with the variations in the strains to which the propeller blades are subjected. Thus
when from the pitching of the vessel for example the propeller becomes more or
less uncovered by water the consequent diminution of strain will allow of the
springs on the shaft inside the vessel moving the plungers and thereby forcing some
liquid into the buffer cylinders in the boss so as to press the pistons against the
shanks of the blades and the movement thus taking place will through the lever
cause the throttle or cut-off valve to correspondingly diminish the supply of steam
to the engines.
Instead of the communication for the liquid being by a central bore or passage
through the shaft or by a pipe or pipes placed in such bore, it may be by one or
more small pipes placed in grooves formed in the outside of the shaft or placed
outside of the shaft excepting at bearings or couplings and at the stern pipe, at which
last part the gun-metal sheath of the shaft may be made of sufficient thickness for
the pipes to be placed in grooves formed inside of it.
The hydraulic buffers or simple strong metallic or other springs may be applied
to the blade shanks to give them a yielding character and thus avoid breakage
from concussion without any connection being necessarily made with the throttle
or cut-off valve of the engines. And on the other hand when metal or other springs
are applied instead of the hydraulic buffers their movements may be transmitted
by rods or chains through a bore in the shaft or through pipes to the interior of the
vessel and to the throttle or cut-off valve.
There may be hydraulic buffers or springs to meet the forward strain or thrust
of the blade shanks as well as those for meeting the rotative strains or torsion; or
single hydraulic buffers or springs may be applied at suitable angles to meet both
strains. When the blades are arranged for yielding to both strains their shanks
may be jointed to the rings which connect them to the shaft so as to be capable of
the necessary motions, or the shanks may be made with balls at their inner ends to
work in sockets formed in the boss.
In a second arrangement the propeller blades are connected to or swung on the
shaft or on pins by rings or ring pieces as in the first arrangement, but they are
made capable of feathering or turning being formed with collared shanks capable
of turning in sockets in the ring pieces. Hydraulic buffers or metal or other springs
are applied for meeting the strains of the blades, and the movements caused by
variation in such strains are made to vary the obliquity of the blades or to feather

page_text: them to a small extent, by short levers fixed in the blade shanks and connected by
links to fixed points in the boss, or by means of one or more teeth gearing with
fixed teeth in the boss, or by any equivalent means. The hydraulic buffers or
springs may be made to act on the throttle or cut-off valve of the engines as in the
first arrangement as well as to feather or turn the blades. The several blades may
swing on the shaft independently of each other or if preferred the several ring
pieces may be fixed to an additional ring or they may be otherwise connected so as
to move together.
In a third arrangement the blades and boss and shaft are combined as in the
second arrangement but complete feathering is obtained automatically by the use
of the hydraulic buffers or pistons, the liquid acted on by such pistons being forced
through passages in the boss to act on suitably placed pistons of sufficiently smaller
diameter to give the required travel, such smaller pistons being arranged to act on
the blade shanks by links and levers or teeth and being pressed by springs in the
direction for setting the blades fore and aft. With this arrangement, on the pro-
peller being made to rotate, the strains caused by the resistance of the water acting
through the blades on the hydraulic buffers or pistons will bring about the setting
of the blades in the positions for propelling. There may be separate small pistons
for feathering each blade of a propeller or a single piston fitted to work in a
cylinder or bore in the shaft or in the boss may be used to act on all the blades;
whilst uniformity of setting of all the blades of a propeller may be secured by
fitting a toothed ring in gear with teeth on the several blade shanks. The throttle
or cut-off valve of the engines may be acted on (as hereinbefore described) by
means of the hydraulic buffers or pistons as well as the feathering apparatus.
In a fourth arrangement instead of applying the hydraulic buffers or pistons
between the blade shanks and the boss of the propeller, they are applied between
the adjacent ends of the shaft lengths at any convenient coupling, being arranged
for rotative strains, or for end ways or thrust strains, or for both strains. In one
modification arranged for rotative strains, the shaft ends are made each with four
or other convenient number of projecting parts, for interlocking with each other;
and the projections of the forward shaft end are formed with cylindrical cavities
which are fitted with the hydraulic buffers or pistons. The outer parts of such
buffers or pistons bear on the projections of the after shaft end, and they communi-
cate to the liquid the strain which they bear when the shaft rotates. The cylinders
or cavities communicate with small cylinders or barrels fitted with rams or plungers
which move with a sliding grooved ring on the shaft and are pressed by springs;
and the grooved ring acts on a lever connected to the throttle or cut-off valve of
the engines. In a modification arranged for endway strain or thrust, one shaft-
length end is formed as a short cylinder and the adjacent shaft-length end is formed
as a ram to work through packed glands or with cupped leathers or other packing
into the cylinder, the clutch projections of the coupling being arranged either
inside or outside of the cylinder. The cylinder space communicates with the
small cylinders or barrels fitted with plungers which are connected to a sliding
grooved ring and other parts as in nodifications hereinbefore described.
The hereinbefore described arrangement of shaft couplings with hydraulic buffers
or pistons and appliances for deriving, governing or controlling movements thereby
from variations in the rotative or torsional strains is advantageously applicable in
many cases in which motive power is transmitted by rotating shafts.
In a fifth arrangement the hydraulic buffer or piston apparatus at a coupling of
the screw propeller shaft is combined with feathering apparatus inside the boss.
The liquid acted on by the buffers or pistons or ram of the coupling acts through a
pore or pipe passing along the shaft on a piston working in a cylinder in the end of
the shaft or in the boss such piston being pressed on its outer side by a spring and
acting on the mechanism by which the blades are feathered.
In a sixth arrangement the propeller blades are made with collared shanks which
re held in sockets or bearings formed for them in the boss, parts of such bearings
consisting of movable blocks which on being keyed up after the parts are in their

page_text: places retain the blade shanks in their bearings or sockets. Eccentric pins or slots
are formed on the inner ends of the blade shanks or on lugs thereon and are acted
on for feathering the blades by slots or pins on a ring piece fitted to slide on the
shaft and itself acted on by a key passing through the shaft and through a
hydraulic piston piece in a central cavity in the shaft. The sliding ring piece
instead of being between the blade-shank ends and the shaft may be abaft or
forward of the shanks and be connected to the shanks by links, which arrange-
ment will allow the shanks to reach nearer to the shaft. In this arrangement the
action of the liquid may be produced by pumps temporarily connected to the shaft
or operating through jackets on the shaft so as to be independent of the shaft's
rotation; and two or more cylinders may be used instead of the single central one;
such cylinders being formed or fitted in the boss but quite distinct from other
internal parts of the boss.
Instead of the feathering of the propeller blades being effected by means of a
hydraulic piston at the propeller worked by liquid from a shaft coupling inside the
vessel as in the fifth or sixth arrangements, such piston may be near the coupling
and its action be transmitted by a rod passing through the bore in the shaft to the
propeller. Or such rod may be worked by means of a spring or springs applied at
the coupling without the herein before described intervening hydraulic apparatus.
In a seventh arrangement the propeller blades formed with collared shanks are
held in bearings consisting partly of movable blocks fixed by keys or wedges as in
the sixth arrangement but pressing on the blade shanks and with these keys
formed or connected with hydraulic pistons acted on by liquid passing through a
pipe or pipes from the interior of, the vessel, and they are loosened when the blades
are to be turned or feathered and are tightened again to hold or assist in holding
the blades in the positions into which they are shifted. In some cases the tighten-
ing blocks are of a helical form and encircle or partly encircle the blade shanks.
Any suitable one of the hereinbefore described feathering arrangements may be
adopted in this arrangement of propeller, the pipe or pipes for the passage of the
liquid by which the feathering is to be effected as well as the pipe or pipes for the
liquid which acts on the bearing block keys being arranged in connection with the
shaft in any of the ways herein before explained. Inside the vessel each set of
pipes communicates with a separate jacket encircling the shaft but stationary and
adapted to the shaft with water-tight packed glands. Pipes connect the stationary
jackets with pumping apparatus by means of which water may be pumped into or
withdrawn from the jackets for the purpose of loosening and setting or turning and
tightening the propeller blades independently of the rotation of the shaft.
Instead of the springs and hydraulic plungers which act together being carried
on the propeller or other rotating shaft as hereinbefore described; one or more
cylinders with plungers or rams may be fixed apart from the shaft and have a
spring or springs applied to it, such one or more cylinders communicating with a
fixed jacket surrounding the shaft and fitted to it with packed glands or other
packing, whilst the interior of the jacket communicates with pipes or passages on
or in the shaft and leading to the hydraulic buffers at the shaft coupling, or at the
propeller.
Instead of the main blades of the propeller being arranged to act by hydraulic
buffers or springs on mechanism connected with the throttle or cut-off valves of the
engines, small subsidiary blades (not necessarily oblique) may be fitted to the
propeller for that purpose. Or two or more small blades may be applied abaft the
propeller, being fixed on the projecting end of a shaft passing through a bore or
central passage in the main shaft to a coupling or other part inside the vessel there
to be connected by apparatus analogous to what is hereinbefore described with the
throttle or cut-off valve of the engines.
In connection with any of the herein before described arrangements dials or other
indicating appliances may be used to show within the vessel the positions of the
propeller blades, also to show the positions of tightening wedges where they are
used. In many cases the indicator may be worked by the lever described as con-

page_text: nected to the throttle valve of the engines, or by a similarly moved lever, and in
some cases chains or rods or wires may be led from the propeller through the
hydraulic pipes or through special pipes, bores, or grooves in the shaft or its gun-
metal sheath to the interior of the vessel there to act on the indicator, the chains
or rods or wires being kept tight where necessary by springs. Similarly such
chains or rods or wires may be connected to and act on the throttle or cut-off valve
instead of or in addition to appliances hereinbefore described.
When indicators such as are herein before referred to are acted on through
hydraulic apparatus by the rotative strain of the shaft the indications being in
correspondence with the strains can be taken as measures thereof and when the
speed of the shaft is taken into account will measure and show the power that is
being at any time transmitted by the shaft whether it be a propeller shaft or any
other rotating shaft.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Howard Pullar in the Great Seal Patent Office on the 29th November
1878.
«
HOWARD PULLAR, of Perth, in the County of Perth, North Britain, Engineer.
JMPROVEMENTS IN AND CONNECTED WITH SCREW PROPELLERS AND THEIR SHAFTS
AND IN PART APPLICABLE FOR GOVERNING OR CONTROLLING OR FOR MEASURING
THE POWER TRANSMITTED BY OTHER ROTATING SHAFTS."
My said Invention comprises various improvements in and connected with screw
propellers and their shafts, and some of these improvements relate to the governing
or controlling of the motion of the shafts and are in part applicable in the case of
other rotating shafts, and also for measuring the power transmitted by rotating
shafts.
It is an object of one part of my Invention to obtain improved constructions or
modes of combining the parts of non-feathering and of feathering screw propellers.
Other parts of my Invention relate to modes of feathering the blades or altering
their obliquity; and to the apparatus for effecting the feathering operation and my
Invention also comprises means or appliances for governing or controlling the
motive-power apparatus through the action of the strains to which the blades of
the propeller are individually subjected, or of the strains to which the shaft is
subjected or of both those strains. Several modifications each consisting of a
screw propeller with the apparatus connected with it, become developed out of the
various modes in which it is possible to combine the portions appertaining to the
several parts of my Invention as hereinbefore indicated.
And in order that my said Invention and the manner of performing the same
may be most readily understood I at once proceed to describe my various improved
arrangements with the aid of seven Sheets of explanatory Drawings which are

page_text: hereunto appended and in which the same reference letters and numerals are used
to mark the same or corresponding parts wherever they are repeated.
One arrangement (hereinafter referred to as the first) of my improved screw
propellers is shown upon Sheet, 1, of the accompanying Drawings. Figure, 1, is a
plan showing the propeller with portions of blades broken off, and a part of the
shafting with portions broken away. Figures 2, 3, 4, are transverse sections of the
shafting, and Figure, 5, is a longitudinal section corresponding to Figure, 1. Figure, 6,
is a plan of the propeller boss with one of the blade shanks in section, and Figure, 7,
is a transverse section of the boss; whilst Figure, 8, is an inside elevation of a cap
fixed on the back of the boss. In this arrangement the propeller blades, B, are
secured in their sockets in the boss by ring pieces, 1, of steel or other suitable
metal which encircle the shaft, S, (or which might fit on separate pins parallel or
oblique to the shaft) each such ring piece, 1, being fixed or jointed to the root
or shank, R, of its blade or forged or otherwise formed on such shank. In the
Drawing each ring piece, 1, is shown as formed with a box, 2, which is square
externally and is formed internally with a cylindrical (or other) socket to fit on
the blade shank, R, to which it is secured by a key. The propeller is represented
as having three blades and one ring piece, 1, is made with a single ring, those of
the other blades being made with two each in positions to admit of one pair
being between the other pair and of the single ring being in the middle. The
construction so far described is applicable to a rigid-bladed propeller the blade
shank, R, in that case filling the socket in the boss; but in the arrangement now
being described the blades, B, are allowed a limited movement in their sockets in
the boss, in a direction round the shaft, S, and the blades bear by their shanks on
piston buffers or cushions, 3, held in cylinders or recesses, 4, formed for them in the
boss such cylinders, 4, containing water or other suitable liquid the pressure of
which resists the strain to which the blade is subjected when propelling. In the
modification shown on Sheet, 1, of the Drawings the part bearing on the piston
buffer, 3, is an inclined projection, 5, formed on the side of the box, 2, which is fixed
on the blade shank, R. The several buffer cylinders, 4, communicate by branch pipes
or passages, 6, 7, with a central pipe, 8, which is entered through a bore formed
through the shaft, S. The central pipe, 8, projects from the outer end of the shaft, S,
and is there bolted to the inside of a cap, C, fixed on the back of the propeller boss,
this cap being formed with hand holes to give access to the inside of it. Passages, 7,
formed in the cap, C, branch from its centre where a communication is formed with
the central pipe, 8, and these passages, 7, communicate with the passages, 6, formed in
the boss itself and leading to the buffer cylinders, 4. At the first or any convenient
coupling or other part of the shaft, S, inside the vessel, the central pipe or passage, 8,
communicates with a number of small hydraulic cylinders or barrels, 9, placed round
the shaft, and having plungers, 10, fixed to or bearing against a sliding grooved
ring, 11, which encircles the shaft, S, and is acted on by a number of springs, 12,
which are guided on rods and have their other ends bearing on screwed studs
which are adjustable in a collar, 13, formed or fixed on the shaft. The ring, 11, is
made in two halves, bolted together on the shaft and is guided by means of grooves
formed on its inside to work on longitudinal feathers fixed on the shaft. A cylin-
drical shell, 14, is shown enclosing the springs, 12, but is not essential. The grooved
ring, 11, acts independently of the rotation of the shaft on a lever, 15, on a fixed
centre; and this lever, 15, is connected to the throttle or cut-off valve of the engines
and acts on it in accordance with the variations in the strains to which the
propeller blades are subjected. Thus when from the pitching of the vessel, for
example, the propeller becomes more or less uncovered by water the consequent
diminution of strain will allow of the springs, 12, on the shaft, S, inside the vessel
moving the plungers, 10, and thereby forcing some liquid into the buffer cylinders, 4,
in the propeller boss so as to press the pistons, 3, against the shanks, R, of the
blades, B, and the movement thus taking place will, through the lever, 15, cause
the throttle or cut-off valve to correspondingly diminish the supply of steam to
the engines. The connection of the lever, 15, with the throttle or cut-off valve of

page_text: the engines may be made in a variety of ways, but in the arrangement shown on
Sheet, 1, the lever, 15, is a bellcrank lever and has one arm connected by an
adjustable link, 16, to a lever, 17, on a shaft, 18, which extends to the engine room
and there has fast on it a pulley, 19, connected by a chain, 20, to a pulley, 21, on the
throttle-valve spindle, 22, on which is fitted a clutch and lever, 23, for putting the
connections into or out of gear, the valve spindle 22, also having on it a lever, 24, to
be connected to the usual hand gear.
Where the power transmitted from the lever, 15, is not of itself sufficient to
readily move the throttle valve or cut-off valve gear, a steam or hydraulic cylinder
may be provided for that purpose its valve being in that case the part to which the
lever, 15, is to be connected.
Instead of the communication for the liquid being by a central bore or passage
through the shaft, S, or by a pipe, 8, or pipes, placed in such bore it may be by one
or more small pipes placed in grooves formed in the outside of the shaft, or placed
outside of the shaft excepting at bearings and at the stern pipe, at which last part
the gun-metal sheath of the shaft may be made of sufficient thickness for the pipes
to be placed in grooves formed inside of it.
The hydraulic buffers, 3, or simple strong metallic or other springs may be applied
to the blade shanks to give them a yielding character and thus avoid breakage from
concussion, without any connection being necessarily made with the throttle or
cut-off valve of the engines. And on the other hand when metal or other springs
are applied instead of the hydraulic buffers their movements may be transmitted
by rods or chains through a bore in the shaft, or through pipes, to the interior of
the vessel, and to the throttle or cut-off valve gear.
There may be hydraulic buffers or springs to meet the forward strain or thrust of
the blade shanks as well as those for meeting the rotative strains or torsion; or
single hydraulic buffers or springs may be applied at suitable angles to meet both
strains. When the blades are arranged for yielding to both strains their shanks, R,
may be jointed to the rings, 1, which connect them to the shaft, S, so as to be capable
of the necessary motions, or the shanks may be made with balls at their inner ends
to work in sockets formed in the boss.
In the arrangement shown on Sheet, 1, an extremely small movement of the blade
shanks, R, in their sockets in the boss is provided for, but this I believe will be
sufficient for the contemplated action upon the liquid and its transmission to the
engines. A greater extent of movement of the blade shanks in their sockets can
however be easily provided for, and a mode of doing so is hereinafter shown in a
modification in which a slight feathering or change of pitch of the blades accom-
panies the movement of their shanks in the sockets. With so small & movement as
that provided for in the arrangement shown on Sheet, 1, the very slight change of
angle of the shank projections, 5, relatively to the piston buffers, 3, requires no further
precaution than the making of the piston buffers very slightly coned or rounded on
their peripheries. The piston buffers, 3, may be packed by means of cup leathers as
in ordinary hydraulic apparatus, or in any other suitable manner; or metallic
diaphragms may be substituted for the pistons and packing as hereinafter
explained.
On the forward side of the socket piece or box, 2, of each blade shank, R, there is
fixed a plate of brass or gun-metal to bear on a number of pieces, 25, of lignum
vitæ or equivalent material fixed in the boss at the forward side of the socket, the
object of this arrangement being to reduce the frictional resistance which the forward
thrust of the blades tends to occasion to the movement of the blade shanks in their
sockets. In Figure, 1, stopcocks, 26, are shown as fitted to the shaft, S, (near the
barrels, 9,) for introducing liquids into the central pipe or bore, 8, and parts in
communication therewith, these stopcocks being made with screwed nozzles for
having pipes coupled to them.
On Sheet, 2, of the accompanying Drawings there is shown a modification of my,
first arrangement, and one in which whilst the shaft details and those inside the

page_text: vessel remain the same, the strains to which the propeller blades, B, are subjected are
communicated to the transmitting liquid in a more direct manner. Figure, 9, is an
inside elevation of the boss cap, C, and Figure, 10, is a plan of the propeller and
shafting with parts broken away. Figures 11, 12, 13 are transverse sections of the
shafting. Figure, 14, is a back elevation of the propeller with the cap, C, removed
and Figure, 15, is a longitudinal vertical section of the propeller and shafting cor-
responding to Figure, 10. Figure, 16, is a face view of one of the blades, B, and
Figure, 17, is a vertical section as at right angles to Figure, 16, whilst Figure, 18,
comprises three sections as taken across the blade. Figure, 19, is a section of the
propeller boss and part of a blade as slightly modified in construction. In this
modification the propeller blades, B, are either formed in the same piece with the
boss as shown in Figures, 10, 14, 15, or each is formed in a separate piece, but
rigidly fixed to the boss as shown in Figure, 19. The main propelling side of each
blade, B, has fixed on it a face or skin plate, 27, of thin sheet metal such as steel,
bronze, or copper (which may be electro-plated with nickel or other protective
metal), and between this skin plate, 27, and the body of the blade, B, a shallow space
is formed which communicates by a passage, 28, with the passage, 7, in the boss cap, C,
leading to the central pipe or bore, 8. The skin plate, 27, being slightly flexible serves
to communicate a pressure corresponding to that acting on its outer surface to the
liquid enclosed under it; and whilst this pressure on the liquid is partly met by
pressure due to centrifugal action on the liquid; still variations in the pressure will
be transmitted through the central pipe, 8, and act on the apparatus inside the vessel
as in the modification shown on Sheet, 1, and herein before described. The skin
plate, 27, is attached to the blade, B, by a sufficient number of screws or rivets round
its edge and so as to be quite watertight; and it is also attached at a number of
points distributed over its surface to raised parts formed for the purpose on the
metal of the covered part of the blade; whilst shallow channels are formed in the
same part to facilitate the movement of the liquid-all as will be clearly understood
from Figures 15 to 18. The ring, 11, is shown as fitted with adjustable stops, d, to
limit its movement in either direction.
A second arrangement of my improved screw propellers is shown on Sheet, 3, of
the accompanying Drawings, Figure, 20, being a plan of the propeller, and shafting
as with parts broken away, Figures 21, to 25, transverse sections of the shafting
and Figure 26, a longitudinal section corresponding to Figure 20, Figure, 27, is a
plan of the propeller showing one blade in end view; and Figure, 28, is a transverse
section of the propeller boss. Figure, 29, is a part section similar to Figure 28,
showing a slightly modified detail. Figure, 30, is an inside elevation of the boss
cap, C. The propeller blades, B, are connected to or swung on the shaft, S, by rings
or ring pieces, 1, as in my first arrangement but they are made capable of feathering
or turning to a certain extent, being formed with collared shanks or roots, R, capable
of turning in sockets in boxes 2, formed in the same pieces with the rings, 1, but in
halves which are bolted together to enclose the collared shanks.. Hydraulic
buffers, 3, are applied as in my first arrangement (or it might be metal or other
springs) for meeting the strains of the blades, and for transmitting them to apparatus
inside the vessel; and the movements caused by variation in such strains are made
to vary the obliquity of the blades or to feather them to a small extent, by short
levers, 29, fixed in the blade shanks, R, and formed with spherical ends on which
blocks are fitted to work in short recesses, 30, formed in the side of the socket in the
boss. The levers, 29, project through slots formed for them in the boxes, 2, and make
the shanks, R, and blades B, turn when any movement of the shanks in the socket
in the boss takes place. The levers, 29, might be connected by links to fixed points
in the boss, or instead of them one or more teeth formed on each shank might gear
with fixed teeth in the boss. The parts shown on Sheet, 3, are constructed to admit
of more movement of each blade relatively to the boss than in the modification
shown on Sheet, 1, and to meet requirements arising from this circumstance the
hydraulic cylinders, 4, and piston buffers, 3, are in Figure, 28, shown as being curved

page_text: concentrically with the shaft: or a spherically-ended block, 31, may as shown in
Figure, 29, be interposed between the shank projection, 5, and the piston buffer, 3;
the cylinder, 4, and piston buffer, 3, being in that case straight.
The several propeller blades, B, may swing on the shaft, S, independently of each
other, as in the modifications shown on Sheets, 1, and 3; and hereinbefore described;
or if preferred the several ring pieces, 1, 2, may be fixed to an additional ring, or
they inay be otherwise connected so as to move together. When the several blades
can move independently of each other, the strain or action transmitted along the
central pipe, 8, will be an average of the strains acting in the several hydraulic
cylinders, 4; and in the arrangement shown on Sheet, 3, and herein before described
there will be a compensating action which will be more important and advan-
tageous the greater the diameter of the propeller is. An increased rotative strain
on any one blade causes the pitch of that blade to become finer through the action
of the lever, 29, and vice versa; and with given conditions of rotation and resistance
an increase in the pitch of a blade causes an increased rotative strain thereon and
vice versa. It follows that any differences of resistance to the several blades due
to their different positions at any given moment, will have the effect of causing
the several blades to assume correspondingly different obliquities, so that their
rotative strains may be equal, or nearly. so. Thus, when any blade is uppermost
and nearer the water surface so as to experience less resistance than a blade that is
lowermost the pitch of the upper blade will become coarser and that of the lower.
blade finer, and during each revolution each blade will gradually change its pitch
in accordance with the changing resistance it will experience. These changes will
not produce any action inside the vessel as the average pressure of the liquid will
remain the same or nearly so; but if from the pitching of the vessel or other
cause the entire propeller should experience a diminished resistance then the average
pressure of the liquid will become diminished, and the springs, 12, will then act so as
to diminish the supply of steam to the engines. If desired the apparatus for acting
on the throttle or other valve may be dispensed with the other parts being used
only for equalising the strains on the several blades. Figure, 25, is a section showing
the application of several comparatively weak springs 12, instead of a few strong
ones.
In a third arrangement, instead of applying the hydraulic buffers or pistons (3)
between the blade shanks and the boss of the propeller, they are applied between
the adjacent ends of the shaft lengths at any convenient coupling, being arranged
for rotative strains or for endways or thrust strains or for both strains. A modifi-
cation arranged for rotative strains is shown on Sheet, 4, of the accompanying
Drawings, Figure, 31, being a transverse section, and Figure, 32, a sectional side
clevation representing portions of two lengths of shafting at the coupling between
which the hydraulic apparatus is applied. Figures, 33, and 34, are transverse sec-
tions and Figure, 35, is a sectional side elevation with the shafting as turned a little
from the position in which it is shown in Figure, 32, Figure, 36, is another trans-
verse section; and Figures 37, and 38, are an enlarged section and face view of one
of the hydraulic cylinders, whilst Figure 39, is a plan corresponding to Figure, 32.
The shaft ends are made each with four (or it might be any other convenient
number of) projecting parts K, L, for interlocking with each other, and the projec-
tions, K, of the forward shaft end are formed with cylindrical (or other conveniently
shaped) cavities 4, which are fitted with buffers or blocks, 3, acting like pistons,
being fixed on diaphragms, 32, of thin sheet metal, such as steel, bronze, or copper
and attached by means of rings, 33, and screws to the edges of the cylinders, 4.
These diaphragms, 32, which are by preference slightly corrugated between the
blocks, 3, and the edges of the cylinders, 4, whilst forming a watertight joint admit
of as much movement of the blocks, 3, as is necessary for communicating variations
of strain to the liquid in the cylinders, 4. These cylinders, 4, communicate by
passages, 34, with the hydraulic cylinders or barrels, 9, and through them the liquid
acts on parts like those hereinbefore described with reference to Sheet, 1, for acting
on the throttle or cut-off valve gear of the engines. Figure 40 is a transverse

page_text: section, Figure 41, a sectional side elevation, Figure, 42, another transverse section,
and Figure, 43, another sectional side elevation with the shaft turned a little; all
representing a modification resembling that last herein before described, but having
the hydraulic cylinders 4, fitted with piston buffers, 3, packed with cup leathers or
otherwise. The diaphragm blocks or piston buffers, 3, of either modification and
which are carried by the projections, K, of the forward shaft length, bear on the
projections, L, of the after shaft end, and they communicate to the liquid the strain
which they bear when the shaft rotates.
Figure, 44, on Sheet, 5, of the accompanying Drawings is an enlarged section
showing the application of the diaphragm, 32, and the buffer or block, 3, to the
hydraulic cylinders, 4, when placed in the propeller boss as in my first arrangement
herein before described. The diaphragm, 32, and the cylinder, 4, may be of an oval
form.
Figure, 45, is a sectional plan and Figure, 46, is a transverse section showing a
modification of my improved apparatus as arranged between two shaft lengths for
acting by endway strain or thrust. One shaft-length end is formed as a short cylin-
der, 35, and the adjacent shaft-length end is formed as a ram, 36, to work into the
cylinder, 35, through a packed gland, or it might be through cup leathers or other
packing. The clutch projections of the coupling are represented as formed inside
the cylinder, 35, where the bearing surfaces which are made numerous can be kept
clean and be lubricated by the oil or other liquid in the cylinder so as to keep the
frictional resistance to the relative longitudinal movement of the shaft lengths as
small as possible. If preferred however or more convenient in any case the clutch
projections may be placed outside of the cylinder, 35. The cylinder, 35, commu-
nicates with the barrels, 9, and the variations of the thrust or endway strain are
communicated by the liquid to the plungers, 10, working in the barrels and through
them to the apparatus arranged as hereinbefore described for acting on the throttle
or cut-off valve gear of the engines.
Instead of applying the hydraulic apparatus for deriving a governing or
controlling action from the endway strain or thrust of a screw-propeller shaft upon
the shaft itself such apparatus may be quite as effectually and in some respects
more conveniently applied to the thrust bearings ordinarily used with screw-
propeller shafts. Such an arrangement is shown on Sheet, 5, Figure, 47, being a
sectional plan, Figure 48, a transverse vertical section, Figure, 49, a sectional side
elevation and Figures, 50 and 51, other transverse vertical sections. The usual
grooved thrust-bearing brasses, 37, fitted to castiron holders are carried so as to be
capable of a slight longitudinal movement in a castiron box or frame, 38, bolted
down upon a bed plate, 39, and having a cover, 40, bolted over the part of it
containing the brasses, 37, with their holders. At the forward end, the box casting,
38, has formed on it a half block, 41, on which an upper half block, 42, is bolted so
that the two encircle the shaft S; and the compound block, 41, 42, has formed in
its back face four cylinders, 4, which are fitted with diaphragms (32) and blocks or
buffers 3. On these buffers, 3, bear the forward ends of the holders of the bearing
brasses, 37, and the pressure is communicated to liquid in the cylinders 4. The
cylinders 4, communicate by passages in the block, 41, 42 with each other and with
a barrel, 9, having working in it a plunger, 10, the outward movement of which is
resisted by a spring, 12. The outer end of the plunger is connected to a lever, 17, on
a shaft, 18, which transmits the movements to the engine room.
On Sheet, 6, of the accompanying Drawings there is shown a modification of
hydraulic apparatus which is comprised in my Invention and is designed for fixing
the shanks of screw-propeller blades in their sockets in the boss when the blades
have been feathered or adjusted in any position. This fixing apparatus is applicable
along with various kinds of apparatus or mechanism for feathering or turning the
blades, but to avoid complexity no feathering apparatus is shown on Sheet, 6, the
propeller delineated thereon being supposed to be one of moderate size and one, the
blades of which may be adjusted separately by means of a key rod passed down a
pipe above the propeller at the stern of the vessel. Figure 52 is a transverse

page_text: vertical section as through the propeller boss; Figure, 53, is an inside elevation of
the boss cap, C, Figure 54, is a longitudinal section; Figure, 55, is a transverse
section at the coupling; and Figure, 56, is a longitudinal section of the boss as taken
through one of the blade shanks. Each blade shank, R, is made with collars, 42, 43,
and fits into a bearing one half of which is formed in the body of the boss. The
other half bearing consists of a block, 44, which is fitted into a socket in the boss so
as to be capable of a limited movement to and from the half bearing that is formed
in the boss itself. In a recess formed in the boss so as to be across the back of the
movable block, 44, there is fitted a wedge, 45, which when forced in one direction
jams the movable block, 44, firmly against the blade shank, R. The wedge, 45, is
made with cylindrical ends which are packed with cup leathers and work in small
cylinders, 46, 47, formed at the ends of the wedge recess; and passages, 48, 49, are
formed in the boss and cap, C, to put the cylinders, 46, 47, in communication with a
pipe, 50, passing through a bore along the shaft and with a pipe, 51, passing along
the centre of the pipe, 50. The pipes, 50, and, 51, are connected in a manner that
will be easily understood from Figure, 54, with stopcocks, 52, 53, fitted to the
shafting and adapted for being coupled to the pipes of a pump by which the liquid
in the cylinders, 46, 47, can be forced and drawn as required for moving the wedges,
45, into or out of the positions in which they cause the blocks, 44, to grip the blade
shanks, R. Instead of the pipes, 50, 51, being one inside the other they may be
arranged side by side in the same shaft bore, or two bores along the shaft may be
substituted for them.
Instead of the springs (12), and hydraulic plungers (10) and parts which act with
them being carried on the shafting (S) as hereinbefore described with reference to
Sheets 1 to 4, of the accompanying Drawings; one or more cylinders with plungers
or rams may be fixed apart from the shaft and have a spring or springs applied to
it or them, such one or more cylinders communicating with a fixed jacket surround-
ing the shaft and fitted to it with packed glands or other packing, whilst the
interior of the jacket communicates with pipes or passages (8) on or in the shaft and
leading to the hydraulic buffers (3) at the shaft coupling or at the propeller. In a
similar way the pipes, 50, 51, of the apparatus shown on Sheet, 6, and hereinbefore
described, might be made to communicate with stationary packed jackets encircling
the shaft, so as to admit of the wedges, 45, being moved independently of the rotation
of the shaft.
Instead of the main blades of the propeller being arranged to act by means of
hydraulic buffers or springs on mechanism connected with the throttle or cut-off
valves of the engines, small subsidiary blades (not necessarily oblique) may be fitted
to the propeller for that purpose. Or two or more small blades may be applied
abaft the propeller being fixed on the projecting end of a shaft passing through a
bore or central passage in the main shaft to a coupling or other part inside tho
vessel there to be connected by apparatus analogous to what is hereinbefore
described with the throttle or cut-off valve of the engines.
In connection with any of the hereinbefore described arrangements dials or other
indicating appliances may be used to show within the vessel the positions of the pro-
peller blades, also to show the positions of tightening wedges where they are used.
In many cases the indicator may be worked by the lever (15) described as connected
to the throttle or cut-off valve of the engines or by a similarly moved lever; and
in some cases chains, or rods, or wires may be led from the propeller through the
bydraulic pipes or through special pipes, bores, or grooves, in the shaft or in its gun-
metal sheath, to the interior of the vessel there to act on the indicator, the chains,
or rods, or wires being kept tight where necessary by springs. Similarly such chains,
or rods or wires may be connected to and act on the throttle or cut-off valve
instead of or in addition to appliances hereinbefore described.
My hereinbefore described arrangements of shaft couplings with hydraulic buffers
or pistons and appliances for deriving governing or controlling or indicating move.
ments thereby from variations in the rotative or torsional strains, are advantageously
applicable in many cases in which motive power is transmitted by rotating shafts.

page_text: The hydraulic buffers or parts for causing the strain to act on a confined liquid may
be arranged at the coupling between two shaft lengths as in the case of the screw-
propeller shafting herein before described, but in some cases it is convenient to
arrange the parts differently although with precisely the same action and effect.
An example is shown in Figures, 57, and 58, on Sheet, 7, of the accompanying
Drawings, these Figures being horizontal and vertical sections showing part of the
main or crank shaft, 54, of a single-cylinder factory engine with the flywheel 55,
and with the spurwheel, 56, for communicating the motion to the factory shafting.
The flywheel, 55, is keyed on the crank shaft, 54, as usual, but the spurwheel, 56,
which is made with a large boss, 57, is mounted loosely on the crank shaft, 54,
between the fly wheel, 55, and a collar, 58. The flywheel centre is made with clutch
projections, K, and the spurwheel boss or centre, 57, is made with clutch projections,
L, to engage with those, K, of the flywheel. The flywheel projections, K, are formed
with hydraulic cylinders (4) and fitted with buffer blocks, (3), attached to diaphragms
(32) as in the arrangement hereinbefore described with reference to Figures 31, to
39, on Sheet 4. The cylinders (4) communicate with an annular passage, 59, formed
in the flywheel centre and this passage communicates with two hydraulic cylinders
or barrels, 9, in which work plungers, 10, fixed to or bearing on a grooved ring, 11,
carried on the crank shaft, 54. The ring, 11, is drawn towards the flywheel by ten-
sionally applied spiral springs, 12, and it acts on a lever, 17, on a shaft, 18, which
transmits the movements to the throttle or cut-off valve gear of the engine. Instead
of the lever, 17, (or 15 of other modifications) being arranged to act on the throttle
or other valve it may be arranged to control the engine or prime mover by means
of a brake or other apparatus.
When indicators such as are hereinbefore referred to are acted on through
hydraulic apparatus by the rotative strain of the shaft, the indications being in
correspondence with the strains can be taken as measures thereof, and, when the
speed of the shaft is taken into account, will measure and show the power that is
being at any time transmitted by the shaft whether it be a propeller shaft or any
other rotating shaft. A portable dynamometer or power measurer embodying the
features referred to, is shown in Figures, 59, to 63, on Sheet, 7, of the accompanying
Drawings, Figures, 59, and 61, being end elevations; Figure, 60, a vertical section as
at right angles to Figures, 59 and 61; Figure 62, an oblique section; and
Figure 63, a plan. On a castiron frame, 60, fitted with wheels, 61, to facilitato
transport, there is mounted in suitable bearing a horizontal shaft, 62, having formed
on it (or it might be fixed on it) a pulley, 63, to receive a belt from a prime mover.
A second pulley, 64, to receive a belt to transmit power to any machine to be driven
or which might have a brake applied to it, is mounted loosely on the shaft, 62, and
the two pulleys, 63, 64 are formed with counterpart clutch projections, K, L. These
clutch projections, K, L, are arranged as in modifications of apparatus herein before
described, the projections, K, of one pulley, 63, being made with cylinders (4) fitted
with diaphragm buffers, 3, such cylinders communicating with a passage, 65, in the
centre of the shaft, 62. In cases wherein the strains intended to be dealt with are
not too great the diaphragms (32) connecting the buffers or blocks, 3, to the parts,
K, may be made of leather or other suitable flexible material. The pipe, 66, of a
pressure gauge, 67, is entered through a stuffing box into the passage, 65, so that the
rotative strain due to the power that is being transmitted at any time between the
pulleys, 63, 64, will be indicated on the gauge. A speed indicator, 68, (which may
be of any convenient and sufficiently accurate kind) is shown as fixed on the
frame, 60, beside the pressure gauge, 67, its internal mechanism being driven by
means of a pulley, 69, arranged at the back of it to receive a cord from a pulley
formed or fixed on the end of the shaft, 62. The scales of the pressure gauge, 67,,
and speed indicator, 68, may be made such that a simple multiplication of the joint
indications will give the power in horses or any other predetermined units. Or a
steam engine indicator or similar instrument may be substituted for the simple
pressure gauge, and be arranged to trace a diagram on paper moved either uniformly
by a timekeeper or by the shaft, 62. When the motion of the paper is derived from.

page_text: the shaft, 62, a timekeeper may be arranged to mark it at minute or other
intervals; and in this way a complete record of the power transmitted will be
automatically obtained.
In any of the hereinbefore described arrangements of apparatus too great a
sensitiveness or quickness of action of the confined liquid can be prevented by
making the passages sufficiently small; and if desirable screw plugs can be fitted
to the passages to admit of the effective size of passage being adjusted.
In my Provisional Specification relative hereto some contrivances are described
to which I have hereinbefore made no reference; with respect to them however
I have decided to make no claim and it is therefore unnecessary to describe them
herein.
Having thus particularly described my said Invention and the manner of per..
forming the same I have to state that I do not restrict myself to the precise
details herein described or delineated and that I do not claim every separate
detail which I have had occasion to describe or refer to, but that what I believe to
be novel and original and claim as the Invention secured to me by and in terms
of the herein before in part recited Letters Patent is :
1. The combination of parts herein before described with reference to Sheet, 1, of
the accompanying Drawings.
2. The securing of screw-propeller blades in sockets in the boss by means of ring
pieces strung on the shaft or on separate pins as hereinbefore described.
3. The attaching of the blades to the boss so as to be capable of a limited move-
ment in their sockets, combined with the use of buffers or pistons by means of
which the strains of the blades act on a confined liquid substantially as and for
the purposes herein before described.
4. The transmitting of strains corresponding to those to which the blades are
subjected, by means of a confined liquid contained in cylinders or spaces at the
propeller wherein the strains are communicated, also in passages leading from such
cylinders or spaces along the shafting into the interior of the vessel, and also in
cylinders or barrels fitted with plungers on which the liquid can act substantially
as and for the purposes herein before described.
5. The combination of parts herein before described with reference to Sheet, 2, of
the accompanying Drawings.
6. The confining of a liquid under skin plates on the propelling sides of the
blades for the purpose of transmitting strains corresponding to the pressures on the
blades substantially as herein before described.
7. The fitting of hydraulic buffers or metallic or other springs in connection with
the shanks of the propeller blades to give the blades a yielding character as herein-
before described.
8. The combination of parts hereinbefore described with reference to Sheet, 3, of
the accompanying Drawings.
9. The fitting of levers (29) or equivalent parts to the blade shanks to feather
or turn the blades when the shanks move in the sockets in the boss in obedience
to changes of strain acting through the shanks on hydraulic buffers, whether the
confined liquid in connection with the buffers communicates only with the buffers
of the several blades or also with governing or controlling apparatus inside the
vessel substantially as and for the purposes herein before described.
10. The combination of parts herein before described with reference to Figures,
31, to 39, on Sheet, 4, of the accompanying Drawings.
11. The combination of parts hereinbefore described with reference to Figures,
40 to 43, on Sheet, 4, of the accompanying Drawings.
12. The introduction of hydraulic buffers or pistons between the coupling parts
of screw-propeller, and of other rotating shafts or equivalent mechanisin, in order
hat pressure corresponding to the rotative strain communicated through the
coupling parts may be imparted to a confined liquid for governing controlling or
ndicating purposes substantially as hereinbefore described."

page_text: 13. The combination of parts hereinbefore described with reference to Figures,
45 and 46 on Sheet, 5, of the accompanying Drawings.
14. The combination of parts hereinbefore described with reference to Figures,
47 to 51, on Sheet, 5, of the accompanying Drawings..
15. The governing or controlling of screw-propeller engines by means of a
confined liquid acting on hydraulic plungers or rams pressed against the liquid by
springs, such confined liquid being subjected to the rotative or endway strains
acting through the propeller or shafting by means of apparatus substantially such
as is bereinbefore described.
16. The securing of the shanks of screw-propeller blades in the boss by means of
movable bearing pieces and wedges acted on by hydraulic pistons and liquids
substantially as hereinbefore described with reference to Sheet, 6, of the accom-
panying Drawings.
17. The fitting of screw propellers with small subsidiary blades to be acted on
and transmit strains or movements to the interior of the vessel for governing or
controlling or indicating purposes as herein before described.
18. The combination of parts hereinbefore described with reference to Figures,
57, and 58, on Sheet, 7, of the accompanying Drawings.
19. The combination of parts herein before described with reference to Figures,
59 to 63, on Sheet, 7, of the accompanying Drawings.
In witness whereof I the said Howard Pullar have hereunto set my hand
and seal this Twenty-eighth day of November, in the year of our Lord
One thousand eight hundred and seventy-eight.
Witness
EDMUND HUNT
Patent Agent
Glasgow.
HOWARD PULLAR. (L.S.)