Year: 1888

page_text: I, STEPHEN ALLEY, of Sentinel Works, Polmadie, in the County of Renfrew,
North Britain, Engineer, do hereby declare the nature of this Invention, to be as follows.
that is to say :-
My said Invention has for its object to construct in an improved manner screw
propellers and apparatus connected therewith suitable for sailing vessels fitted with
auxiliary steam power, and for yachts or other vessels intended to be sometimes
propelled with sails alone.
In carrying out my Invention I make a screw propeller with four or other convenient
number of blades which are arranged to fold (using this term to distinguish the blades
from feathering blades). The boss on the shaft has radial slots formed in it to receive
the roots of the blades, these roots being formed as joint eyes, and the blades being
jointed to the boss by means of pins passed through the parts of the boss at the sides
of the slots and through the joint eyes of the blades. On parts of the edges of the
roots or joint eyes of the boss, either worm wheel or spurwheel teeth are formed, and
on a small shaft passing through the main shaft made tubular for the purpose, there is
formed or fixed either a screw or worm or as many sets of rack teeth as there are
blades. The blades are folded or opened out by turning the small shaft if provided
with a screw or by moving it on end if made with rack teeth. When opened the
blades bear against stops or shoulders formed on the boss, such stops or shoulders
assisting the blades to sustain the propelling strain. In folding the blades turn on
their joints with the outer ends describing quadrants down to the axis of the shaft;
and in order to keep them steady when closed a strong pintle is fixed on the ship's
stern post in the line of the axis of the shaft and a ball or block of rubber is fixed on
the pintle for the ends of the blades to close on when folded down. When thus folded
the blades present practically no obstruction to the passage of the vessel through the
water under sail.
Dated this Twentieth day of February 1888.
EDMUND HUNT,
Per pro David Ferguson,
Applicant's Agent.

page_text: Improvements in or Connected with Screw Propellers.
I, STEPHEN ALLEY, of Sentinel Works, Polmadie, in the County of Renfrew, North
Britain, Engineer, 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, that is to say :-
My said Invention has for its object to construct in an improved manner screw
propellers and apparatus connected therewith suitable for sailing vessels fitted with
auxiliary steam power, and for yachts or other vessels intended to be sometimes
propelled by sails alone.
My Invention consists in making a screw propeller with four or other convenient
number of blades, which are arranged to fold (using this term to distinguish the blades
from feathering blades). The roots of the blades are made with eyes and are inserted
in slots formed in the boss of the shaft and jointed by pins passed through the slots
and eyes of the blades. The blades are folded by means of worm wheel or spurwheel
teeth formed on the roots of the blades and gearing with a screw or worm or rack
teeth formed on a small shaft passing through the main shaft, this small shaft being
either turned or moved on end to open or fold the blades.
And in order that my said Invention and the manner of performing the same may
be properly understood I hereunto append a sheet of explanatory drawings to be
hereinafter referred to and showing my improvements.
Figure, 1, on the accompanying sheet of drawings is a side elevation of my
improved screw propeller showing the blades in the open position. Figures, 2, and 3,
are end and side elevations respectively as with the blades in the folded position.
Figures, 4, and 5, are a sectional side elevation and a transverse section showing one
modification of parts for folding or opening the blades and figures, 6, and 7, are
sectional views of a second modification. In these drawings the same reference
numerals are used to mark the same or like parts wherever they are repeated.
In carrying out my Invention the boss, 7, on the shaft, 8, has radial slots or
recesses, 9, formed in it to receive the roots, 10, of the blades, 11, these roots, 10,
being formed with joint eyes, and the blades, 11, being jointed to the boss, 7, by means
of pins, 12, passed through the parts of the boss, 7, at the sides of the slots, 9, and
through the joint eyes in the roots,, 10, of the blades. In the modification shown in
figures, 4, and 5, worm wheel teeth, 13, are formed on parts of the edges of the
roots, 10, of the blades, 11, and these worm wheel teeth, 13, gear with a screw or
worm, 14, formed on a small shaft, 15, which passes through the main shaft, 8, made
tubular for the purpose. The blades, 11, are folded or opened out by turning the
small shaft, 15, by any suitable means.
In the modification shown in figures, 6, and 7, spurwheel teeth, 16, and rack
teeth, 17, for each of the blades, 11, are substituted for the wormwheel teeth, 13, and
worm, 14, hereinbefore described; and the blades, 11, are folded or opened out by
moving the small shaft, 15, on end. This movement is effected by forming a screw, 18,

page_text: on the inner end of the small shaft, 15, the screw, 18, working in an internally
screwed wormwheel, 19, which gears with a worm, 20, having the end of its spindle, 21,
squared to receive a handled box key for turning it by. When opened the shanks of
the blades, 11, bear against the boss, 7, at the forward ends of the slots or recesses, 9,
and are thus enabled to sustain the propelling strain. In folding, the blades, 11, turn
on their joints with their outer ends describing quadrants down to the axis of the
shaft, 8, and in order to keep them steady when closed a strong pintle, 23, is fixed on
the ship's stern post, 24, in the line of the axis of the shaft, 8, and a ring, 25, (or it
might be a ball or block of rubber) is fixed on the pintle, 23, for the ends of the
blades, 11, to close upon when folded down. When thus folded the blades, 11,
present practically no obstruction to the passage of the vessel through the water
under sail.
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The improved construction or arrangement of screw propeller and parts connected
therewith, the blades being jointed to the boss in a manner to fold towards the axis
and mechanism being provided for folding or unfolding the blades substantially as and
for the purposes hereinbefore described.
Dated this Nineteenth day of November 1888
EDMUND HUNT,
Applicant's Agent.