Improvements in Propellers for Boats and the like.
Year: 1898

page_text: Improvements in Propellers for Boats and the like.
I, THOMAS BRIDGES HEATHORN, of 10, Wilton Place, Knightsbridge, in the
County of Middlesex, Gentleman, do hereby declare the nature of this invention
to be as follows:-
This invention relates to the construction of propellers of that class in which
the vessel is propelled and steered, or its motion retarded and reversed by the
action of a single vibrating stern paddle or rudder to which is imparted a compound
motion comprising a primary oscillation about the axis of the rudder post, due
to the motor effort, and a secondary oscillation about an independent axis, due
to the turning or tilting of the rudder blade, caused by the resistance of the water
or other medium when so oscillated about the rudder post axis; and has for its
principal object to ensure the return of the propeller blade to its normal position
after being displaced by the aforesaid secondary oscillation.
In one arrangement of propeller constructed according to this invention and
suitable for the propulsion of a boat, the rudder as a whole is connected to a vertical
rudder post or shaft working in suitable bearings secured to the stern of the
boat, and on the said shaft is mounted the requisite cranks or levers for connecting
it to the actuating mechanism. From the lower end of this shaft projects another
shaft inclined to and preferably integral with it, and on this projecting shaft is
suitably mounted near its longitudinal lower edge the rudder propeller blade proper
so as to be capable of oscillating to a limited extent about its axis. It will thus
be seen that as the main or rudder shaft is oscillated, the rudder propeller blade
as a whole is oscillated with it, while, at the same time, it is caused, by the
resistance of the water, to also oscillate about its longitudinal pivotal or secondary
axis.
In order to limit the angle of oscillation of the rudder propeller blade, and that
it may be automatically returned to its normal and central or vertical position
after an oscillation, the rudder post is provided with a crank in which is secured
a pin working in a block free to slide in a guide strap forming the central part
of a rod capable of sliding in guide bushes screwed or otherwise adjustably
secured in the walls of a cavity in the end of the rudder blade adjacent to the
said crank, one of the walls being preferably detachably secured to the blade, and
the axis of the said slide rod being arranged perpendicular to the plane of the
propeller blade. On the said slide rod, and between the sides of the guide strap
and the guide bushes, are helical springs under compression and which, when the
propeller blade is displaced from its normal position or plane of rest, immediately
return it to its central position on the removal of the displacing force.
In a modified arrangement of propeller constructed according to this invention
the pivotal or secondary shaft of the propeller blade is secured to or integral with
it and works in suitable bearings connected to the main or rudder shaft and has
formed on it screw threads or helices of coarse pitch, and engaging in this thread
is a nut having guide notches sliding on fixed feathers or guide ribs parallel to

page_text: The axis of the said shaft and secured to an outer fixed casing so that as the shaft
rotates the nut is caused to slide axially on it and vice versa. On both sides of
the before mentioned nut are helical springs surrounding the propeller blade
pivotal shaft and which tend to force the nut, and with it the shaft and propeller
b'ade, into its central or normal position, when displaced; and in order that the
springs may always force the nut into a determinate central position they may
be provided with end disc plates arranged to abut against stops so placed as to
leave a space between the said discs equal to the width of the nut.
When propelling the boat ahead the propeller blade trails astern, but in order
to reverse the forward motion and propel the boat astern it is only necessary to
reverse the position of the blade so as to point ahead.
Dated this 28th day of January 1898.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.
openers for Boats and the like.
I, THOMAS BRIDGES HEATHORN, of 10, Wilton Place, Knightsbridge, in the
County of Middlesex, Gentleman, do hereby declare the nature of this invention
and in what manner the same is to be performed to be particularly described and
a:certained in and by the following statement:—
This invention relates to the construction of propellers of that class in which
the vessel is propelled and steered, or its motion retarded and reversed by the
action of a single vibrating stern paddle or rudder to which is imparted a compound
motion comprising a primary oscillation about the axis of the rudder post, due
to the motor effort, and a secondary oscillation about an independent axis, due
to the turning or tilting of the rudder blade, caused by the resistance of the water
or other medium when so oscillated about the rudder post axis; and has for its
principal object to ensure the return of the propeller blade to its normal position
after being displaced by the aforesaid secondary oscillation.
In the accompanying drawings:
Fig. 1 is a sectional elevation of the stern of a boat fitted with a propeller
constructed according to this invention, Fig. 2 is an end elevation of propeller,
Fig. 3 is a plan through line A-B of Fig. 2, Fig. 3 is a similar view to Fig. 3
howing a buffer cylinder attached to give a cushioning effect at the end of the
troke Fig. 4 is a cross section of spring buffer box of propeller, Fig. 4* is a detail
view, and Fig. 5 is a plan of driving mechanism. Fig. 6 is a sectional elevation
of a modified arrangement of propeller and Fig. 7 is a cross section through C-D
of Fig. 6.
Figs. 8, 9 and 10 are end elevation, side elevation and plan of a part of a
further modified form of propeller.
Referring to Figs. 1 to 5 of the drawings inclusive, the rudder as a whole is
connected to a vertical screw-threaded rudder post or shaft a passing through a
screw-threaded sleeve terminating upwardly in a journal working in a split cross-
head through whose ends pass two screw threaded spindles d having mounted on
them pinions e gearing with a worm f on a spindle g rotated by the hand wheel h
through pinions il. It will be seen that by rotating the screws & the crosshead c
is raised or lowered and the shaft a rotated thus causing the rudder to take up any
desired mean position and thereby steer the boat. The sleeve b is free to slide
axially in a bearing sleeve m free to rotate in a bearing n but is prevented from

page_text: rotating therein by a feather n sliding in a corresponding groove in the said
bearing sleeve. The bearing sleeve m terminates upwardly in a crosshead o whose
ends are connected by rods p to the driving sway lever q itself connected by rods r
to sliding crossheads s connected to cranks t operated by any suitable motor. It
will thus be seen that while the driving mechanism causes the rudder to oscillate
through a constant angle at each revolution of the driving cranks it can also
be caused to take up any mean position thereby affecting the propulsion and steering
at the same time.
The lower edge of the rudder propeller blade proper vis mounted on a shaft w
so as to be capable of oscillating to a limited extent about its axis. It will thus
be seen that as the main or rudder shaft a is oscillated, the rudder propeller blade v
as a whole is oscillated with it, while, at the same time, it is caused, by the
resistance of the water, to also oscillate about its longitudinal pivotal or secondary
axis w.
In order to limit the angle of the secondary oscillation of the rudder propeller
blade, and that it may be automatically returned to its normal and central or
vertical position after an oscillation, the rudder shaft to is provided with a crank &
in which is secured a pin y working in a block z free to slide in a guide strap a a
forming the central part of a rod ab capable of sliding in guide bushes a c Ecrewed
into the ends of a spring box a d in the end of the rudder blade adjacent to the
said crank, the axis of the said slide rod being arranged perpendicular to the
plane of the propeller blade. On the said slide rod a band between the sides of the
guide strap aa and the guide bushes, are helical springs a e under compression
and which when the propeller blade is displaced from its normal position or plane
of rest, immediately return it to its central position on the removal of the dis-
placing force.
In the modified arrangement of propeller shown in Figs. 6 and 7 the pivotal
or secondary shaft wo of the propeller blade is secured to or integral with it and
works in suitable bearings in the casing af and has formed on it screw threads or
helices of coarse pitch, and engaging this thread is a nut a¹ having guide
notches sliding on fixed feathers or guide ribs a m parallel to the axis of the said
shaft and secured to the casing af so that as the shaft w rotates the nut is caused
to slide axially on it. On both sides of the beforementioned nut are helical
springs a e surrounding the pivotal shaft w and which, when the propeller blade v
is displaced from its vertical position by the resistance of the water during a
primary oscillation about the rudder post, tend to force the nut al into its central
position and thereby return the propeller blade v to its normally vertical position.
The casing af is connected by bevel pinions aga h to the reversing shaft a s
passing through the hollow main rudder shaft a.
The locking, steering, and reversing devices are similar to those described in
Specification of Patent No. 20177 of 1894.
In order to limit the angle of oscillation of the propeller blade about its pivotal
axis a crank an on spindle w works in a pocket a o in the casing, the angle being
limited by the impact of the crank against the sides of the said pocket.
In the arrangement shown in Figs. 8 to 10 instead of the propeller being reversed
as in Fig. 6 by bevel gear the end of spindle or shaft w terminates in a coarsely
pitched screw a pon which a nut a q is mounted and connected through cranks ar
to suitable gear above by means of which the crank may be actuated so as to force
the nut axially along the screw and thereby cause the shaft w to rotate through
the required angle.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
--
1. A propeller for boats comprising a rudder blade hinged on its lower edge
to an inclined shaft, a buffer box at right angles to the plane of the rudder blade,
a spindle sliding in the end caps of the said buffer box and being connected at its

page_text: centre to a crank on the aforesaid inclined shaft, and helical springs in the said
buffer box substantially as described for the purpose set forth.
2. The arrangement and construction of propeller rudder and rudder actuating
and controlling apparatus substantially as described with reference to Figs. 1 to 5
of the drawings.
3. The arrangement and construction of propeller rudder with screwed shaft and
nut and enclosed springs substantially as described with reference to Figs. 6 and 7
of the drawings.
4. The arrangement and construction of propeller rudder having a screwed
extension engaging with a nut connected with the controlling gear substantially as
described with reference to Figs. 8 to 10 of the drawings.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, Agents.