Apparatus for Propelling and Steering Boats and other Navigable Vessels.
Year: 1889

page_text: Date of Application, 23rd Dec., 1889
Complete Specification Left, 6th Sept., 1890-Accepted. 25th Oct.. 1890
PROVISIONAL SPECIFICATION.
Apparatus for Propelling and Steering Boats and other Navigable
Vessels.
I, HENRY BARCROFT, of The Glen, Newry, in the County of Armagh, Director of
the Dundalk and Newry Steam Packet Company, do hereby declare the nature of this
invention to be as follows:-
My invention relates to apparatus for propelling and steering boats &c. described in
the Provisional Specification to my application for Letters Patent dated 17th August
1889 No. 13019, such apparatus consisting mainly of two independent sets of pro-
peller blades mounted on main and tubular shafts carried in fixed bearings above the
water line, such sets of propeller blades being made to revolve in contrary directions
and provided with means whereby the angular position of the blades of each set
relatively to the shafts could be varied so that by varying such angle to the same
extent in both sets, the motion of the vessel could be increased, decreased or reversed,
while by adjusting the one set to a different angle from the other set, the boat would
be steered to the one or the other side according to the manner in which the angular
positions of the two sets of blades were varied.
According to one part of my present invention I arrange the main and tubular
shafts carrying the two sets of blades and the driving gear actuating the same in such
manner that the shafts with two sets of propeller blades can be made to assume
varying angular positions relatively to the longitudinal axis of the vessel, so that the
vessel will be steered to port or to starboard according to the angular position which
the shafts and propellers are made to assume, on account of the angular thrust
exercised by the propeller shafts.
For this purpose I mount the shafts with their overbanging sets of propeller blades
upon a bed plate or frame arranged to swivel or turn horizontally on a pivot or other-
wise upon the deck or other support above the water line in a similar manner to the
bed plate of a steam crane, and T either also mount the motor engine, whether this be
a steam engine with its boiler or dynamo motor or troadles to be worked by feet, upon
the said bed plate so as to turn with the shaft, or the motor engine or treadles may be
situated at some other part of the vessel and the motion be transmitted from it
through articulated or flexible shafting or through pullies and bands.
The turning of the bed plate for bringing the propeller shaft into the required
position can be effected in various ways, such as by hand by means of a tiller and
catch for holding it in position, or by a rack and pinion or worm wheel worked either
by hand or by steam steering gear of known construction.
According to another improvement, instead of providing two sets of revolving
radial propeller blades as described in the previous application, each forming as it
were, a propeller wheel, I provide only two single propeller blades or sculls cach
having an arm that is either hinge jointed at its upper end to a vertical slide carried
by a fixed support or framing or itself works in a slide trunnioned to the framing,
while at an intermediate point of its length each arm is formed with a circular loop or
ye, the one fitting on an eccentric or crank pin on the main propeller shaft and the
ther on an eccentric on the tubular shaft, which is made to revolve in the contrary
lirection, as described in my said previous Specification.
Thus, by the rotation of the main and tubular shafts their eccentrics, when passing
hrough the lower half of their revolution, will cause the propeller blades to be
mmersed in the water and will at the same time move them forward in opposite
ransverse directions so as to propel the vessel, while when passing through the upper
alf of their revolution the eccentrics will raise the two blades out of the water and
ill at the same time move them back again in the transverse direction. The arms of
D

page_text: the blades may be made adjustable in length and angle as described in the said
Specification No. 13019 of 1889 so as to suit the varying load line of the vessel, or
speed required, and they may also be made removeable so as to allow of their
being replaced by blades of greater or less area. This arrangement of recipro-
cating propeller blades may be applied either to the above described arrangement
of angularly adjustable propeller shaft, or to the arrangement with fixed propeller
shaft.
The above described blades paddles or sculls may either be arranged to act with
variable angular positions for both propelling at variable speeds, and for steering or
with variable positions for only propelling at variable speeds, the steering being
effected by means of a rudder, or again, they may work with a fixed angular position,
the variation of speed being effected by varying the speed and direction of rotation of
the propeller shaft in the ordinary way.
In the above described arrangement, instead of driving the one propeller blade
by a tubular shaft on the main propeller shaft, the one blade may be driven by
the main shaft and the outer propeller be situated in line with the main shaft and
receiving rotation in a contrary direction therefrom by suitable gearing.
In this case both propeller blades can be driven by cranks from their respective
shafts instead of by eccentrics.
There may be provided more than one pair of propeller blades as above described,
and the blades may be arranged to feather during their motion.
Dated this 23rd day of December 1889.
ABEL & IMKAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Apparatus for Propelling and Steering Boats and other Navigable
Vessels.
I, HENRY BARCROFT, of The Glen, Newry, in the County of Armagh, Director of
the Dundalk and Newry Steam Packet Company, do hereby declare the nature of
this invention and in what manner the samo is to be performed to be particularly
described and ascertained in and by the following statement :-
My invention relates to apparatus for propelling and steering boats &c. described in
the Specification to my Letters Patent dated 17th August 1889 No. 13019 such
apparatus consisting mainly of two independent sets of propeller blades mounted on
main and tubular shafts carried in fixed bearings above the water line, such sets of
propeller blades being made to revolve in contrary directions and provided with means
whereby the angular position of the blades of each set relatively to the shafts could
bo varied so that by varying such angle to the same extent in both sets, the motion of
the vessel could be increased, decreased or reversed, while by adjusting the one set to
a different angle from the other set, the boat would be steered to the one or the other
side according to the manner in which the angular positions of the two sets of blades
were varied.
According to one part of my present invention I arrange the main and tubular
shafts carrying the two sets of blades and the driving gear actuating the same in such
manner that the shafts with two sets of propeller blades can be made to assumo
varying angular positions relatively to the longitudinal axis of the vessel, so that the
vessel will be steered to port or to starboard according to the angular position which
the shafts and propellers are made to assume, on account of the angular thrust
exercised by the propeller shafts.
For this purpose I mount the shafts with their overhanging sets of propellor blades
upon a bed plate or frame arranged to swivel or turn horizontally on a pivot or
otherwise upon the deck or other support above the water line in a similar manner to
the bed plate of a steam crane, and I either also mount the motor engine, whether
this be a steam engine with its boiler or dynamo motor or treadles to be worked by
feet, upon the said bed plate so as to turn with the shaft, or the motor engine or

page_text: treadles may be situated at some other part of the vessel and the motion be transmitted
from it through articulated or flexible shafting or through pullies and bands.
The turning of the bed plate for bringing the propeller shaft into the required
position can be effected in various ways, such as by hand by means of a tiller and
catch for holding it in position, or by a rack and pinion or worm wheel worked either
by hand or by steam steering gear of known construction.
According to another improvement, instead of providing two sets of revolving
radial propeller blades as described in the previous application, each forming as it
were, a propeller wheel, I provide only two single propeller blades or sculls each
having an arm that is either hinge jointed at its upper end to a vertical slide carried
by a fixed support or framing or itself works in a slide trunnioned to the framing,
while at an intermediate point of its length each arm is formed with a circular loop
or eye, the one fitting on an eccentric or crank pin on the main propeller shaft
and the other on an eccentric on the tubular shaft, which is made to revolve in
the contrary direction, as described in my said previous Specification.
Thus, by the rotation of the main and tubular shafts their eccentrics, when passing
through the lower half of their revolution, will cause the propeller blades to bo
immersed in the water and will at the same time move them forward in opposite
transverse directions so as to propel the vessel, while when passing through the upper
half of their revolution the eccentrics will raise the two blades out of the water and
will at the same time move them back again in the transverse direction. The arms of
the blades may be made adjustable in length and angle as described in the said
Specification No. 13019 of 1889 so as to suit the varying load line of the vessel, or
speed required, and they may also be made removeable so as to allow of their being
replaced by blades of greater or less area. This arrangement of reciprocating
propeller blades may be applied either to the above described arrangement of
angularly adjustable propeller shaft, or to the arrangement with fixed propeller
shaft.
The above described blados, paddles or sculls may either be arranged to act with
variable angular positions for both propelling at variable speeds, and for steering or
with variable positions for only propelling at variable speeds, the steering being
effected by means of a rudder, or again, they may work with a fixed angular position,
the varation of speed being effected by varying the speed and direction of rotation of
the propeller shaft in the ordinary way.
In the above described arrangement, instead of driving the one propeller blade by
a tubular shaft on the main propeller shaft, the one blade may be driven by the main
shaft and the outer propeller be situated in line with the main shaft and receiving
rotation in a contrary direction therefrom by suitable gearing.
In this case both propeller blades can be driven by cranks from their respective
shafts instead of by eccentrics.
There may be provided more than one pair of propeller blades as above described,
and the blades may be arranged to feather during their motion.
DESCRIPTION OF THE DRAWINGS.
Figs. 1 and 2, of the accompanying drawings shew respectively a side elevation
partly in section, and a plan of the first hereinbefore described construction of
propelling and steering apparatus.
A and B are two sets of propeller blades mounted on two separate shafts A' and B₁
of which A' is made tubular for the passage through it of the shaft B', the two shafts
being rotated in contrary directions, and the blades of the propellers B being placed
at an opposite angle to those of A, so that the side thrust exercised by the one set will
be counteracted by that of the other set. So far the construction is similar to that
Figs. 1 and 2, of the accompanying drawings shew respectively a side elevation
partly in section, and a plan of the first hereinbefore described construction of
propelling and steering apparatus.
A and B are two sets of propeller blades mounted on two separate shafts A' and B'
of which A' is made tubular for the passage through it of the shaft B', the two shafts
being rotated in contrary directions, and the blades of the propellers B being placed
at an opposite angle to those of A, so that the side thrust exercised by the one set will
be counteracted by that of the other set. So far the construction is similar to that
described in the Specification to my aforesaid former Patent No. 1301989. Instead
however of carrying the shafts A¹ B' in fixed bearings upon the vessel, as described in
my said Specification, I mount them on a swivelling platform e, turning upon a pivot c¹
fixed on the deck of the vessel, so that for stoering, the two sets of propellers can be

page_text: brought into any desired angular position, as indicated by the dotted lines at Fig. 2 by
turning the platform on its pivot. This turning may be effected either simply by a
hand tiller & so that the apparatus is worked in the same way as an ordinary rudder,
or it may be effected by toothed gearing or tiller chains in any known inanner.
The driving machinery for the propeller shafts may either be mounted entirely upon
the platform, as indicated, the crank shaft o, which may be worked either by treadles
or by a small engine, being made to rotate a wheelf by a pinion g, and this motion
being imparted in reversed directions to the two shafts by the bevil gearing h. Or the
motor engine can be situated amidships and the wheel, be driven from it by shafting
and suitable gearing as indicated in dotted lines at Fig. 2. In this case the platform c
can of course be reduced in size.
The propeller shafts A' B' may either be made of sufficient strength to overhang
the stern of the boat without without requiring to be supported at the outer ond by a
framing or the swivelling platform may have projecting bearers, a sufficient distance
apart to allow tho propellers to rotate between thein, so as to offer a support to the
outer ends of the shafts. The propeller arms are by preference made telescopic as
described in my said prior Specification, so as to adjust their length to the draft of
water. The slowing, stopping, and reversing is effected by the engine or treadles in
the usual manner.
Figuros 3 to 6 shew a construction of the propelling apparatus according to the
second herein before described arrangement. Fig. 3 shows a side elevation Fig. 4 an
end elevation Fig. 5 a plan and Fig. 6 an enlarged detail.
In this arrangement there are only two propeller blades A and B, which, instead of
revolving on horizontal shafts receive a reciprocating motion by means of cranks ij,
so as to alternately move in the direction for propelling the boat while immersed in the
water, in a lowerod position, and then to move back again while in a raised position,
out of the water, the angular positions of the blades and their movements being in
contrary directions, as in the proceding case.
The propelling action of both blades might be made to take place at the same time,
but in order to equalize the work on the motor engine I prefer to arrange them to
work consecutively as shewn.
The propeller arms E F are for this purpose connected respectively to the cranks i j
of which is fixed on the shaft k while; is fixed on the shaft 1, which is driven in the
reverse direction to k by means of the bevil gear m situated between the two
propellers.
The upper ends of the arms E F slide through eyes no provided with trunnions that
can turn in bearings p q secured adjustably to uprights rs.
Thus it will be seen that by the rotation of the cranks the blades are made to move
in approximately oval paths, which paths are so adjusted relatively to the water line
that when performing the propelling motion, the blades are immersed in the water,
while when performing the return motion they are raised out of the water.
Figure 7 shews a diagram of the description of motion produced.
The shafts with the propellers as also the uprights rs are all carried by the swivelling
platform pivotted to the deck and carrying any suitable motor engine on the inner
end, which imparts motion to the shaft & by toothed gearing u. The platform is moved
by a tiller handle v as before for effecting the steering by imparting a more or less
angular position to the propellers.
The motor engine might also be arranged amidships and the shaft be driven by
gearing in a similar manner to that indicated at Fig. 2.
For connecting the crank pins to the propeller arms, the latter are constructed of
two separate tubular parts which are screwer or otherwise secured to a central piece w
having an eye through which the crank pin passes.
For the purpose of adjusting the stroke of the propellers, the arms E F, instead of
being arranged as above described may carry moveable sleeves w' shewn to an enlarged
scale at Fig. 6, which are fixed in any desired position on the arm by setting screws a
and which have loops y in which work the pins of the cranks ij.
The propeller armis may be made telescopic as in the first described construction an i

page_text: in order, when they are extended not to increase unduly the extent of their lateral
stroke, the bearings of the upper eyes n can be moved higher up on the uprights r
so as, by removing the trunnion point farther from the crank, to reduce the angle of
the stroke.
The above described arrangement of two opposite sculling blades may also be
employed with the crank shafts in fixed positions on the boat without the swivelling
platform, the steering being in that case effected by an ordinary rudder.
The above described arrangement of two separate propeller shafts in line with each
other for the two sets of propellers, driven in contrary directions by gearing between
the two sets might obviously also be applied to the arrangement of rotary propeller
blades previously described, when the platform is extended to the outer end of the
shafts instead of arranging the one shaft to pass through the other.
The two propeller blades might also be mounted on separate shafts arranged parallel
to each other upon the platform or deck and both driven in opposite directions by the
engine.
By this arrangement the advantage would be gained that the propellers would not
project so far beyond the stern of the boat as with the above described arrangement.
In both the above arrangements the propeller blades and gear may be enclosed above
water line by a suitable casing.
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. In apparatus for propelling boats consisting of two sets of propeller blades
mounted on independent shafts made to revolve in contrary directions, mounting the
propeller shafts upon a turntable or swivelling platform on the deck of the vessel either
with or without the motor engine, the said platform being moved by a tiller or other
steering gear for bringing the propeller shafts and blades into angular positions for
steering substantially as described with reference to Figures 1 and 2 of the drawings.
2. Apparatus for propelling boats consisting of two propeller blades receiving a
reciprocating motion by means of two crank shafts revolving in contrary directions,
the angular position of the one blade being the reverse of that of the other blade, and
the propelling strokes being made to take place in contrary directions when the blades
are submerged, while the return stroke takes place when the blades are raised out of
the water, substantially as described with reference to Figs. 3, 4, 5 and 6 of the
drawings.
3. In propelling apparatus such as is referred to in the preceding claim, mounting
the crank shafts and propeller blades on a turntable or swivelling platform on the deck
of the boat with or without the motor engine, the said platform being moved by means
of a tiller or other steering gear for bringing the propeller shafts and blades into
angular positions for steering, substantially as herein described with reference to
Figs. 3, 4 and 5 of the drawings.
Dated this 6th day of Sentember 1890.
ABEL & IMRAY,
Agents for the Applicant