IMPROVE- MENTS IN SHIPS' PROPELLERS AND APPARATUS IN CONNECTION THEREWITH
Year: 1881

page_text: LETTERS PATENT to Charles Denton Abel, of No. 28, Southampton Buildings,
Chancery Lane, in the County of Middlesex, for an Invention of "IMPROVE-
MENTS IN SHIPS' PROPELLERS AND APPARATUS IN CONNECTION THEREWITH."
A communication from abroad by Johann Anton Andrée, of Esens,
Ostfriesland, Germany.
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel at the
Office of the Commissioners of Patents on the 30th November 1881.
CHARLES DENTON ABEL, of No. 28, Southampton Buildings, Chancery Lane,
in the County of Middlesex. "IMPROVEMENTS IN SHIPS' PROPELLERS AND
APPARATUS IN CONNECTION THEREWITH." [A communication from abroad by
Johann Auton Andrée, of Esens, Ostfriesland, Germany.]
This Invention has reference to a construction of ships' propellers in which flat
blades or vanes are pivotted to a central boss in such a manner that on rotating
the propeller alternately in opposite directions the blades will be made by the
pressure of the water to assume alternately opposite angular positions so as to
propel the boat forward in whatever direction the propeller is rotated.
For this purpose the area of the blade on the forward side of the axis on which
it pivots is inade less than the area on the rear side, so that the blade will, by the
pressure of the water, always be made to assume an angular position (which is
limited by stops) suitable for propelling the vessel forward in whichever way it is
rotated. This construction of propeller is more particularly adapted for propelling
small boats by treadle action, for which purpose the apparatus may be arranged
in various ways. According to one arrangement the propeller is mounted on a
short shaft in front of the rudder in the usual manner, the shaft being provided
with a pulley round which passes an endless band leading up to the deck, and
round a guide pulley in a horizontal position. To the opposite parts of the endless
band are attached cords that are led either over guide pullies to treadles, or they
are provided with handles to be worked by the hand, so that on pulling at theso
cords alternately by the hands or by the action of the treadles the endless band
DR.71

page_text: is made to travel a certain distance alternately in contrary directions, and it thus
causes the propeller to perform a certain number of revolutions first in one
direction and then in the other. There may also be provided two other propellers
on shafts, one on each side of the above mentioned one, and driven therefrom by
means of pullies and endless cords, so that by rotating the middle propeller as
described the two side ones are simultaneously rotated in the same direction.
According to another arrangement the propeller is mounted on the end of a shaft
that passes down in an inclined position from the stern of the boat; the shaft is
mounted with its upper end in bearings on a frame that can swivel on a centre
fixed in the stern of the boat, and it has a pulley round which is led an endless
strap passing over guide pullies in a horizontal direction to a guide pulley in the
forward part of the boat, so that by imparting a to and fro motion to the endless
band by hand or trendle, as above described, the shaft and propeller will be rotated
alternately in contrary directions. The swivelling frame has a handle by which
it can be moved into varying angular positions, and thus the shaft and propeller
in assuming corresponding angular positions relative to the longitudinal axis of
the boat will effect the steering of the latter.
According to another modification one of the said propellers may be mounted
on each side of the boat at any convenient forward position, in brackets passing
down from a transverse bearer overhanging the sides of the boat, the motion being
imparted to the propellers as before by an endless band led over guide pullies
down to each propeller shaft, and receiving a to and fro motion either by hand or
by treadle,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Denton Abel in the Great Seal Patent Office on the
20th May 1882.
CHARLES DENTON ABEL, of No. 28, Southampton Buildings, Chancery Lane,
in the County of Middlesex. "IMPROVEMENTS IN SHIPS' PROPELLERS AND
APPARATUS IN CONNECTION THEREWITH." A communication from abroad by
Johann Anton Andréc, of Esens, Ostfriesland, Germany.
This Invention has reference to a construction of ships' propellers in which flat
blades or vanes are pivotted to a central boss in such a manner that on rotating
tho propeller alternately in opposite directions the blades will be made, by the
pressure of the water, to assume alternately opposite angular positions so as to
propel the boat forward in whatever direction the propeller is rotated.
For this purpose the area of the blade on the forward side of the axis, on which
it pivots, is made less than the area on the rear side, so that the blade will, by
the pressure of the water, always be made to assume an angular position (which is
limited by stops) suitable for propelling the vessel forward in whichever way it is
rotated.
Figs. 1 to 6 of the accompanying Drawings shew a propeller constructed
according to this Invention. Fig. 1 shews an elevation of the same in the position
when revolving to the right; Fig. 2 shews the corresponding plan; Fig. 3 shews
an elevation of the propeller when revolving to the left; Fig. 4 shows the corre-
sponding plan; Fig. 5 shews a side view of the propeller, partly in section; Fig. 5º
shews a section on line A, B, of one of the blades; Fig. 6 shews a plan with the
blades situated in the central position; Fig. 6 shews a section of a blade on
line C, D, and Fig. 6b shews a section on line E, F.
Although the propeller is in all cases shewn with four blades, yet it will be
readily understood that it may have a less or a greater number.
The blades a, which are by preference made somewhat tapering in thickness
towards the edges as shewn, are pivotted on pins c fixed to the boss b of the shaft d.
The blades are held in position by a washer i secured by a pin. In order to limit
the angular motion of the blades to an angle of 90°, the boss b has two pro-
jections or stops f so arranged that the blade in coming in contact therewith
in either extreme position forms an angle of 45° with the axis of the propeller
shaft.
The blades are so formed that the area thereof on the forward side of the axis
on which they pivot is considerably less than that on the rear side of the axis, so.
that in whatever direction the shaft d be made to turn, the blades will, by the
pressure of the water, always be brought into the proper angular position for
propelling the boat forward, the position assumed when the shaft revolves to the
right being that shewn at Figs. 1 and 2, while the position assumed when the shaft
revolves to the left is that shewn at Figs. 3 and 4.
When the propeller is stationary while the boat continues to move onward the
pressure of the water will cause the blades to assume the axial position shewn at
Figs. 5 and 6, and consequently offer the least possible obstruction to the motion,
which is of importance when the boat is required to be propelled by sails as well
as by the propeller. Various arrangements may be employed for imparting the
requisite reciprocating rotary motion to the propeller shaft; it is however preferred
to effect this by means of an endless band, receiving a to and fro motion by means
of two other cords or bands.
Figs. 7 to 9 shew one such arrangement; Fig. 7 shews an elevation, Fig. 8 an.

page_text: underside plan, and Fig. 9 an upper side plan of a boat with the propeller applied
thereto. The boat A is provided with three of the before described propellers
B, C, D, mounted on separate shafts. The middle one C is fixed on the shaft d'
running in bearings m, m', and having a gut pulley n over which passes the
endless gut o which is led up over guide pullies r, r, and round the horizontal
pulley p mounted on a standard q. To the gut o are attached cords 8, 8', the other
ends of which are connected to levers t, t¹, having trendles u, u', that are actuated
by the feet of the operator so as to impart a reciprocating notion to the levers and
consequently a to and fro motion to the endless gut. By this means the propeller C
will be rotated a certain number of times first in one direction and then in the
contrary direction. The propellers B and D are driven from the shaft of C and in
the same direction there with by means of endless guts ³ passing over pullies w on
shaft d' and over pullies x, x, on the shafts of B and D which are carried in forked
brackets, as shewn at Fig. 8.
The rudder is worked in the usual manner by tiller ropes by hand as shewn.
Fig. 10 shews a similar arrangement to that above described with a single
propeller E, whose shaft Z is mounted in bearings y, y', and carries a gut pulley Z¹
driven by the endless gut a² passing round the pulley e³ and led over guide
pullies c³. The cords d, d³, by which the to and fro motion is imparted
to the gut a are in this case provided with loops c³ so as to be worked by the
hands.
Figs. 11 and 11ª shew an arrangement by which the propeller can be applied to
any existing boat without alteration, and wherein the propeller is at the same
time made to serve as rudder. Tho propeller G is fixed on the shaft g³ which is
mounted in bearings in a bracket H in such manner as to pass downwards in an
inclined position into the water, the propeller being consequently also inclined.
The bracket His pivotted at h³, and can be moved upon such pivot by means of
the lever having its fulcrum at whereby the shaft g can be moved so as to
assume a more or less angular position in a horizontal direction relative to the
longitudinal axis of the boat and thus cause the propeller to act as steering
apparatus. The shaft g is driven by the endless gut m³ passing round the pulley n³
on the shaft and led over guide pullies of to the pulley 2 carried by the cross
beam 9. The requisite to and fro motion is, as before, imparted to the gut by
means of the cords 7, 73.
Figs. 12 and 13 also show an arrangement that can be applied to any existing
boat. In this case two propellers I, K, are mounted in brackets hanging down on
ench side of the boat from a crossbeam L. Each propeller shaft has a gut pulley
y3, y, over which passes the endless gut 8 that is led round guide pullies t, t³,
and u to the pulley on the cross beam w³, motion is imparted as before by
means of the cords 22. To increase the hold of the gut upon the pullies y it may
be coiled several times round them as indicated.
Although the improved propeller is shewn as applied only to smaller boats, for
which it is more particularly intended, it will be evident that it can also be
employed with advantage for larger vessels, the arrangements of the driving gear
being suitably modified for this purpose.
Having thus described 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 claim,
First. The improved construction of propellers herein described with reference to
Figs. 1 to 6b of the Drawings, having blades a pivotted on pins c so as to be
capable of turning to an angle of about 45° on each side of the axis of the propeller
shaft, their movement being limited by stops, and their arrangement being such
that whether rotated in the one direction or the other, the pressure of the water
will always cause them to assume a position for propelling the vessel in one and
the same direction.
Second. Constructing the propeller blades a so that the area thereof on one side
of the axial line of their pivot is considerably greater than that on the other side

page_text: whereby they are caused automatically to assume the correct position for propelling
in one and the same direction when alternately rotated in contrary directions,
substantially as herein described.
Third. The combined arrangement of three propellers B, C, D, herein described
with reference to Figs. 7 to 9 of the Drawings, the propeller C being driven by an
endless gut o, cords 8, 8', and treadle levers t, t, while the propellers B, D, are
driven by endless guts from the shaft of propeller C.
Fourth. The arrangement of propeller described, with reference to Fig. 10, driven
by the endless gut a² receiving a to and fro motion by means of the cords ², d³.
Fifth. The arrangement herein described, with reference to Figs. 11 and 11ª, in
which the propeller G is mounted on an inclined shaft g² carried by a swivelling
bracket H so as to assume angular positions relatively to the longitudinal axis of
the boat, whereby the propeller is made to act as steering apparatus.
Sixth. The arrangement herein described, with reference to Figs. 12 and 13 of
the Drawings, wherein two propellers are mounted in pendent brackets one on each
side of the boat and are driven by one and the same endless gut 8º passing over
pullies y³, t, t, u³, and v².
In witness whereof, I, the said Charles Denton Abel, have hereunto set
my hand and seal, this Twentieth day of May, in the year of our Lord One
thousand eight hundred and eighty two.