Improvements in Steering Torpedo Boats and other like Vessels by Means of their Screw Propellers, applicable to Aerial Navigation.
Year: 1891

page_text: Date of Application, 6th Oct., 1891
Complete Specification Left, 27th June, 1892-Accepted, 6th Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in Steering Torpedo Boats and other like Vessels
by Means of their Screw Propellers, applicable to Aerial
Navigation.
We LOUIS ADRIEN BOISSET and LOUIS OCTAVE MERCIER both of 45 Rue
St. Sebastien Paris in the Republic of France Engineers do hereby declare the
nature of this invention to be as follows:-
:-
This invention relating to improvements in or connected with propellers for
torpedo boats and small vessels such as are employed in .naval warfare is also
applicable to apparatus employed for the purposes of aerial navigation and enables
the course to be changed instantaneously without prejudice either to the stability
or steadiness or to the maintenance of the horizontal position of the vessel.
In carrying out this invention as applied to the propeller of a torpedo boat for
example two helices or screws are employed with blades inversely arranged and
rotating in opposite directions in parallel planes on the same axis being arranged
one behind the other in a suitable frame in the stern at the rear of which the rudder
is arranged in the usual manner. The propeller shaft is supported in front of the
screws in a bearing capable of sliding horizontally on a circular guide the bearing
being provided with a plate of corresponding curvature arranged to make a water-
tight joint with the guide and enabling the shaft to be moved within an angle of say
about 90 degrees without uncovering the opening.
One of the propellers is fixed on a hollow shaft and the other propeller is fixed
on a shaft passed through this hollow shaft. The shafts are supported in suitable
bearings at their forward ends and motion in opposite directions is imparted to them
by means of bevel wheels and a vertical shaft receiving rotary motion by means of
a crank and connecting rod or other suitable mechanism. The forward bearings
of the propeller shafts are supported on a plate or frame capable of rotary motion
on a vertical axis coinciding with the axis of the aforesaid vertical driving shaft so
as to enable the propeller shafts to be swivelled in a horizontal plane and placed at
any required angle to the axis of the vessel by means of a toothed wheel gearing
with a toothed quadrant or circular rack attached to the plate or frame carrying
the shafts. This movement may be combined with that of the rudder and placed
under the control of the steersman. By these means a powerful propelling action
is obtained and the vessel is enabled to be manœuvred or the course changed with
great promptitude and without loss either of stability or speed.
Dated this 6th day of October 1891.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Steering Torpedo Boats and other like Vessels
by Means of their Screw Propellers, applicable to Aerial
Navigation.
We LOUIS ADRIEN BOISSET and LOUIS OCTAVE MERCIER both of 45 Rue
St. Sebastien Paris in the Republic of France Engineers 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 :-
This invention relating to improvements in or connected with propellers for
torpedo boats and small vessels such as are employed in naval warfare is also

page_text: applicable to apparatus employed for the purposes of aërial navigation and enables
the course to be changed instantaneously without prejudice either to the stability
or steadiness or to the maintenance of the horizontal position of the vessel.
Attempts have heretofore been made to combine the propeller with the rudder
with the object of performing rapid evolutions without interfering with the stability
of the vessel. In swinging round or altering the course, with one screw the vessels
are compelled to slacken speed and describe a long curve if the stability is to be
preserved and in going astern the rudder is almost powerless. Twin screws
turning in opposite directions placed on each side of the vessel have also failed to
give satisfactory results.
The failures to attain efficient results in this direction have led us to the conclusion
that it is necessary to combine the means for steering and for propelling in one
apparatus and this is the object of our present invention. The screws according
to our invention move at the stern of the vessel about an axis movable in a plane
parallel with the keel. The two short shafts which carry the said screws revolve
about the axis of a bevel wheel which drives them and their bearings are
carried by a horizontal plate working on a centre and actuated by the steering
engine or apparatus.
The shafts provided with the thrust bearings are passed through a horizontal
slot in the stern of the vessel provided with strong curved guides in which the
thrust bearing slides.
The movable screws thus arranged may receive rotary motion from any suitable
part of the vessel and may be placed in any oblique or inclined direction required
for propelling and turning the ship. By the use of our invention we obtain with
certainty a considerable propulsive power with the aid of two screws combined in
such a manner that the screws rotate in opposite directions on the same axis with
equal advantages as regards the propulsion thus enabling the stability of the vessel
to be ensured during its progress and evolutions the latter being capable of
being performed without any necessity for stopping or slackening speed. All
the power of the screws is utilized with advantage as they take the water in
different directions and deliver it in one projection astern and in the axis of the
screws.
The shafts and screws are movable, independently of one another, and can be
placed whilst the vessel is advancing or performing evolutions, in oblique directions
to port or starboard for the purpose of steering the vessel.
The steering being performed by the screws they replace with advantage the
rudder which can be dispensed with.
The apparatus is designed in accordance with the laws of naval construction and
is of a practical nature and easy and certain in its action.
And in order that our said invention may be fully understood we shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 of the accompanying drawings illustrates in longitudinal section the
stern of a vessel provided with movable steering and propelling screws according
to our invention and
Figure 2 is a corresponding plan.
Figures 3 and 4 illustrate, in longitudinal sections, modifications of the arrange-
ments for working the movable screws.
In carrying out our invention we employ two screwe A and B situated in the
same axial line but keyed upon different shafts A' and B' working one within the
other. The screw nearest the stern post is left handed and the other screw is
right handed relatively to the forward motion.
The screw A, is fixed on a hollow shaft A' (Figure 1) arranged in the lower part
of the vessel and supported by a slide C, and a bearing D, and the screw B, is
fixed upon a shaft B', passed through the hollow shaft A' and supported at its
extremity by a bearing D'. Both shafts are arranged in the frame of the stern

page_text: post E, which may be formed in one with a casting F, forming the bed plate of
the mechanism for transmitting motion to the screws and for swivelling them.
A rudder G may be pivoted on the frame of the stern post in the usual manner
if desired.
The slide or plate C is carried by horizontal guides c³ ³ forming the arc of a
circle the centre of which coincides with the vertical axis of the pivot p of a
revolving plate P as hereinafter described; and is capable of moving in the said
guides within an angle of say about 90 degrees. A horizontal opening M is formed
in the stern post so as to admit of this horizontal displacement. A stuffing box or
packing e prevents any leakage between the slide and the guides which are firmly
fixed to the vessel at their port and starboard ends. A stuffing box or packing is
likewise provided at each extremity of the guides. A stuffing box f prevents
leakage past the shaft A'.
"
The pivot p is formed in one with the plate P and works in a footstep bearing 9.
The said plate P runs on rollers h and receives rotary motion from a bevel pinion i
gearing with a circular rack formed upon the said plate P and as the plate P
carries the bearings of the screw shafts as shewn the movement imparted to the
said plate P causes the screws to be swung to port or starboard and act as a rudder
or assist the action of the ordinary rudder without affecting the stability of the
vessel. By these means the great advantage is gained that evolutions can be
performed without slackening the speed of the propeller. The swinging movement
of the screws may take place conjointly with that of the rudder. It can be
produced by any suitable or known means and be controlled by the steersman.
Upon the rotary plate P is arranged a footstep bearing for a vertical cranked
shaft k supported at the other extremity by the frame / by which the bearings D and D'
for the shafts A' and B¹ of the screws A and B are connected to the plate P. The
vertical shaft k receives motion from the motor by means of a crank or in any
other suitable manner and transmits this motion through the bevel wheels ↑ 7ª µ³ to
the shafts A'B' which consequently rotate in opposite directions. The reverse
rotations of the screws A and B ensures equal powerful propelling force and perfect
stability in rapid evolutions.
"
The point of departure of the movement producing the inverse rotation of the
screws is situated upon the same piece (the revolving plate P) as that which is
employed for producing the swinging movement of the screws to turn or assist the
turning of the vessel.
The rotation or propelling and the direction or guiding are thus positively con-.
nected and moreover the arrangement of the screws rotating in opposite directions
enables the course to be changed at full speed without affecting the horizontal.
position of the ship or aërostat which carries the apparatus.
We of course do not limit ourselves to any particular sizes, shapes, dimensions,
proportions, or materials employed in the construction of the apparatus nor as to
its application to any particular class of vessel to be propelled and it will be evident
that the arrangement can be modified in various ways By way of example we
have illustrated two modifications in Figures 3 and 4 Figure 3 illustrates an
arrangement in which the axis of oscillation of the screws A. B is placed in the
stern post itself the movement being controlled, not by a plate, but simply by a
way N in the arc of a circle the tight joint C being carried back behind the axis
of oscillation. The shafts A¹ and B' in this figure receive motion from a dynamo H
acting directly upon a wheel r driving the wheels and and the swinging move-
ment is produced by the aid of a dynamo H¹ acting upon a pinion gearing with
a rack on the plate P¹ situated at the upper part of the vessel and carrying the
dynamo H. Both dynamos may be worked by one series of accumulators O.
21
Figure 4 illustrates another arrangement of the vertical axis. In this arrange-
ment this axis is worked by a plate P and a pinion receiving motion from a
steam engine Q. The axis is provided at its upper part with a wheel B
transmitting motion from a steam engine to the wheels & ³ driving the
shafts A¹ B³ driving the screws A B. In this arrangement the tight joints C¹ C³

page_text: We do not claim either the
nor do we borrow anything
England nor from the system
are arranged on each side of the vertical shaft P.
arrangement of the shafts A'B' or the wheels
from the Debay system which has been used in
employed in Whitehead torpedoes. We would observe also that we do not use the
Cardan steering screw.
•
"
8
The screws may be worked by any kind of motor engine or apparatus such for
instance as gas engines steam engines or dynamos and the vertical axis may be
arranged at any part of the propeller shaft in the interior of the ship.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In torpedo vessels, ships, aërostats and like vessels the combination of two
reversed screws and means for rotating them in opposite directions, a movable slide
working in horizontal circular guides a slot formed in the stern below the deck or
in the lower part of the vessel to admit of the horizontal movement of the screws
and a pivotted piece carrying the screw shafts the whole being arranged in such
a manner as to enable the screws to be moved in the required direction for the
purpose of causing them to participate in the movement of evolution or turning
the vessel and enable the said evolution to be performed without slackening speed
and without affecting the horizontal position or stability of the vessel substantially
as hereinbefore explained.
2. In torpedo vessels, ships, aërostats and like vessels the combination of two
reversed screws rotating in opposite directions and a guide or combination of
curved plates with packings in which works the thrust plate or block of the pro-
peller shafts in such a manner as to prevent leakage at this part substantially as
hereinbefore described.
3. In torpedo boats, ships, aërostats and like vessels the general combination and
arrangement of the apparatus comprising two reversed screws A and B attached
respectively to shafts A' B' rotating in opposite directions, a slide C on the pro-
peller shafts working in horizontal guides &c, a rotary plate P forming the centre
of the lateral movement of the screws and supporting the driving gear by which
the rotary motion is imparted to the screws in opposite directions and also their
lateral movement and enabling evolutions to be performed without slackening
speed substantially as hereinbefore described with reference to Figs. 1 and 2 of the
accompanying drawings.
4. The modifications of the general arrangement claimed and which are illus-
trated by Figures 3 and 4 of the accompanying drawings.
Dated this 27th day of June 1892.
J. H. JOHNSON & Co.,
Agents.