IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS AND APPARATUS FOR PROPELLING THE SAME
Year: 1884

page_text: "
I ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Engineer do hereby declare the nature of this Invention for "IMPROVEMENTS IN
THE CONSTRUCTION OF SHIPS AND APPARATUS FOR PROPELLING THE SAME and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
This Invention relates to vessels propelled by screws, and has for its object the
avoidance of resistance to the progress of the vessel through the water, a better
economy and more complete utilization of the propelling power, and increase in
the buoyancy of the vessel and more rapid velocity of the vessel than has
heretofore been attained with the same expenditure of propelling force, and also a
greater facility of turning, reversing and changing the direction of the course of
the vessel more promptly than has been practicable with a mere steering apparatus.
The nature of this Invention consists in an improved shape of hull by which
provision is made for a different location and operation of propellers in concavities
or recesses, and more effectual and certain access of water to the propelling
apparatus, thus avoiding the racing consequent upon the disengagement of the
propeller from the water.
.
The combination of propellers with such cavities so as to make a downward and
outward reaction.
The combination of propellers susceptible of rotation independently, located on
both sides of the vessel.
The combination of such propellers with the shaft of the motors or engines, so
that the motor and propeller have the same shaft in common or shafts connected
together without the intervention of gearing.
The combination of such propellers with engines susceptible of independent
rotation and at the same time susceptible of connection by their valve operating
mechanism so that they may at the option of the engineer have the same velocity
073

page_text: automatically maintained, or may be run in different directions simultaneously and
with different velocities automatically at relative rates to each other, determined by
the adjustment of the valve operating mechanism in the control of the engineer.
This Invention is applicable with especial advantages to vessels of war, securing
for them a celerity in moving and turning hitherto unequaled with the same weight
of apparatus and expenditure of power.
I will now proceed to particularly describe the mode of making and using this
Invention, referring in so doing to the Drawings annexed.
Figure one, shows a plan.
Figure two, a side elevation.
Figure three, a cross section on the line X X in Figures 1, and 2.
Figures four, five and six, show modifications thereof, and Figure seven, eight,
nine and ten modifications of the details of the motors or engines and propellers.
Figure eleven indicates a direct rotary, engine applied thereto.
Figures twelve, thirteen, fourteen, fifteen, sixteen, seventeen and eighteen,
illustrate the connecting valve operating mechanism of the motors or engines.
The same letters of reference apply to the same parts in the several Figures.
Figures nineteen and twenty show respectively inside elevation and in horizontal
section the propeller; and surrounding portion of the hull drawn on an enlarged
scale, the plane of the section in Figure twenty being indicated by the dotted line
marked Y Y in Figure nineteen, A, represents the hull of the vessel, A1, the bow
thereof, A 2, denotes the midship, section of the vessel, A 3, indicates recesses or
cavities formed in the hull A, forward of midship section, the form of which
cavity is in curved lines or surfaces permitting an easy flow of water into said
cavities from the forward underneath portion and sides of such cavities, and the
easy turning of such current, and a downward and outward discharge thereof, in a
direction parallel or downwardly and outwardly divergent therefrom.
'B, represents the propellers of the kind known as screw propellers, the axes of
which are obliquely directed downwardly and outwardly towards the stern, a
space B1 is provided between the forward portion of the cavities A 3 and the
propellers B, into which spaces water can readily pass to the propellers in the
direction indicated by the arrows in the Drawing; the propellers have their blades
inclined in such direction, that during the forward propulsion of the vessel, the
blades which are outward are descending, whilst those which are inward or
toward the center line of the vessel are rising, the form of the cavity aft of each
.propeller is such as to freely discharge the water from the propeller without abrupt
change in its direction, so that it reacts upon the water in which the vessel is
floating, obliquely downward and outward toward the after part of the vessel thus
measureably relieving the pressure of water upon the sides and bottom of the
boat, and forcibly by the backward reaction projecting the boat forward through
.the water.
The hub B2 of the propeller B should be made in the form of a prolate spheroid
having the arms or blades B 3 attached thereto or made in one piece therewith and
strongly filletted at their point of juncture with the hub, the boss or tube B 4,
through which the propeller shaft projects from the hull of the vessell should be
made conical, and at the line of juncture with the hull should be filletted as shown
in the Drawing in Figure two, so as to avoid any sharp angles which might
produce eddies or breaks in the current passing in the cavity A3 to the propeller.
The shaft C of the propeller, extends into the hull of the vessel and is provided
therein with a thrust bearing and preferably forms a component part of the engine
.shaft.
The engine as shown in Figure seven has a crank formed in the shaft and direct
acting cylinder piston and-connecting rod applied. thereto.
As shown in Figure eight two cylinders are employed with cranks placed
diametrically opposite so as to form the usual type of direct acting compound
marine engine. .
•

page_text: As shown in Figure nine two cylinders are applied having pistons and connecting
rods engaging upon cranks placed at right angles with each other thus forming a
readily reversible engine.
Figure ten shows three cranks formed in the shaft at angles of 120 degrees to
each other to which are applied connecting rods, cylinders and pistons, making
readily reversible compound engines.
4
The shaft of each propeller may be advantageously made angularly adjustible in
the sleeve through which it passes from the interior of the vessel to the water, by
having a second sleeve containing the stuffing box fitted with either a ball and
socket fluid tight joint or an elastic or flexible joint in which case the bed plate
and shaft bearing of the engines are susceptible of adjustment vertically and
horizontally about a fulcrum located at or near the point of passage of the shaft
and stuffing box through the hull of the vessel.
By this arrangement the direction of the angle of action and reaction can be
varied, adjusted, and controlled to meet the varying requirements of propulsion and
buoyancy.
i
The engine E shown in Figure eleven is a direct acting rotary machine consisting
of two engines having revolving pistons E1 and E2 both upon the same shaft
which pistons are of unequal displacement and the supply of steam is admitted to
the engine piston of the smallest displacement at first and afterwards discharged
from the cylinder containging the smallest piston displacement into the cylinder of
greater piston displacement, and from thence exhausted to the condenser, thus
forming a direct acting rotary compound engine.
Each separate propeller B has its own separate shaft and driving engine, distinct
and separate as far as shaft connection is concerned.
D, represents a valve operating mechanism by which the several engines are
connected.
This valve operating mechanism embraces a link motion on each engine
consisting of the usual elements of eccentric rods and shifting links connected
therewith as shown in Figures twelve and thirteen, or instead thereof an adjustible
and reversible eccentric as shown in Figures fourteen and fifteen, the several valve
motions are connected by a series of links and levers operated by, a single rock
shaft D1 and lever D 2 controlled by the engineer, so that when placed in central
position the several reversing and cut-off mechanisms shall all receive steam to an
equal extent and distribute the steam equally to the several engines.
I
When the lever is placed to one side or the other of central position, the
adjustment of the shifting links is changed so that more steam is furnished to one
engine than the other, and the engine so supplied with steam is accelerated in
velocity whilst the other engine with a diminished supply of steam is retarded.
The connection of the links or equivalent reversing and cut-off gear on each
engine is made so that it can be reversed in connection with the rock-shaft D 1,
and lever D 2, controlled by the engineer, and the same manipulations are then
practicable for operating the vessel by each, either or both of its engines in reverse
direction.
The link F connecting the shifting link of each engine in this arrangement is
not fastened permanently to the double arm or lever F 1 on the rock-shaft D 1, but
to a block F 2, which slides in a slot extending to both arms of the lever F 1, and
by moving the block to either arm, the engine link so connected is reversed in
action by the motion of the lever D 2 from the action that would occur when the
block F 2 is engaged in the other arm of the lever F 1.
The propellers as shown in Figures 1, 2 and 3 are located symetrically with their
containing cavities, in Figure 4 they are placed symetrically but at both ends of
the vessel, shown in this Figure is what is known as a double ended vessel having
two bows, and is adapted to sail in either direction, such construction being
especially adapted to monitors and other armor clad vessels.
In the form shown in Figure 5 the cavities A 3 are not placed symetrically nor
are the propellers located symetrically upon the vessel, but on the contrary one is

page_text: placed somewhat aft of the other, so as to afford better arrangement for spaces
inside of the vessel to contain the machinery.
In the form shown in Figure, 6 the propellers and their containing cavities are
arranged upon a vessel having double hulls, so that the vessel may be rotated in
the water or propelled in either direction of the line of their keels..
The oblique downward thrust produced by the propellers produces a lifting
effect which facilitates the motion of the vessel, and by reason of the propellers
being located near to the engines or motors a more prompt action in changing the
course of the vessel is effected:
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is :-
First. The combination of a vessel having concavities forward of the mid-ship
section and below the water line with two or more screw propellers having an
oblique downward and outward thrust located wholly or partially in such
concavities and rotated separately and independently by motors having a driving
shaft in common with each propeller, substantially as and for the purpose set
forth;
Second. The combination of a vessel having concavities in the hull forward of
the mid-ship section and below the water line, adapted to receive and guide the
currents of water to and from screw propellers located wholly or partially therein,
the screw propellers having a downward and outward direction of thrust toward the
stern of the vessel and susceptible of independent rotation, substantially as and
for the purpose set forth.
Third. The combination of independent engines susceptible of varying and
adjustible regulation of speed and direction of motion relatively to each other
with propellers located in cavities of a vessel forward of the mid-ship section, and
having downward and outward rearward thrust, as and for the purpose set forth.
Fourth.. The combination in a vessel adapted to sail in either direction of it's
length of keel of two or more sets of screw propellers having their axes inclined
outwardly and downwardly toward the mid-ship section of the vessel, located
wholly or partially in concavities substantially as and for the purpose set forth.
Fifth. In a vessel having two or more hulls combined in parallel position the
combination of a series of two or more independent engines with screw propellers
having their axes inclined outwardly and downwardly toward the mid-ship
portion, such propellers located in or partially within cavities formed in said hulls,
aft of the bows and forward of the mid-ship section.
Sixth. In a vessel propelled by power internally applied, the combination of
screw propellers located forward of the mid-ship section with projections in the
form of zones, or segments of prolate spheroids surrounded by receding curved
'surfaces, substantially as shown and described.