IMPROVE- MENTS IN THE CONSTRUCTION OF SCREW PROPELLERS
Year: 1854

page_text: · LETTERS PATENT to William Wain, of Brunswick Street, Stamford Street,
in the Borough of Southwark, Engineer, for the Invention of "IMPROVE-
MENTS IN THE CONSTRUCTION OF SCREW PROPELLERS."
Sealed the 9th February 1855, and dated the 16th October 1854.
PROVISIONAL SPECIFICATION left by the said William Wain at
the Office of the Commissioners of Patents, with his Petition, on the
16th October 1854.
I, WILLIAM WAIN, of Brunswick Street, Stamford Street, in the Borough
of Southwark, Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE CONSTRUCTION OF SCREW PROPELLERS" to be as
follows:-
The object of this Invention is to produce a simple and efficient screw
propeller, the blades of which shall be capable of adjustment to any required
angle to suit the run of the vessel to which the propeller is applied. The boss
of the propeller I cast in one piece, with an opening through it to receive the
stems of the propeller blades. These stems are severally set in conical bushes,
which bear against a shoulder on their respective stems, and being bolted to
the boss, hold them securely therein, while at the same time they afford a ready
means of tightening up the blades in their sockets when they have worked
loose by wear. The stems at their inner ends lock into each other, and they

page_text: are provided each with a ring of bevil teeth, into which a pinion takes for
turning the blades and setting them at any required angle. A square socket
is made in this pinion, which is contained in the propeller boss, and into the
socket takes the square end of a shaft, that passes through a hollow shaft
which is secured to the driving shaft of the engine. In the propeller boss a
square socket is formed, to receive the squared end of this hollow shaft. This
mode of connecting the propeller with its shaft is for the, purpose of facili-
tating their disconnection, when such is required. The inner end of the pinion
shaft is feathered to receive a worm wheel, which works into and is driven
by a worm carried by a spindle, which has its bearings in a flange of the
hollow shaft.
By means of a key this worm is rotated, and thus (through the worm wheel
and its shaft) an axial motion is imparted to the pinion in gear with the rings
of teeth on the stems of the propeller blades, and at the same time the blades
are caused to turn in their sockets, and assume any required angle with respect
to the driving shaft. To disengage the propeller, the hollow shaft is drawn
inwards until it is clear of the boss of the propeller, and to shorten this
movement as much as may be, I find it desirable to give the inner shaft an
independent sliding motion. For this purpose I form upon it a circular rack,
into which gears a pinion carried by the hollow shaft. By turning this pinion
the shaft may be slidden forward or backward, as required. An index pointer
is mounted on this shaft to show the angle at which the blades are standing.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Wain in the Great Seal Patent Office on the
16th April 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
WAIN, of Brunswick Street, Stamford Street, in the Borough of Southwark,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixteenth day of October, in the year of our Lord One
thousand eight hundred and fifty-four, in the eighteenth year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said William
Wain, Her special license that I, the said William Wain, my executors,
administrators, and assigns, or such others as I, the said William Wain, my
executors, administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term therein

page_text: expressed, should and lawfully might make, use, exercise, and vend, within
the United Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF SCREW
PROPELLERS," upon the condition (amongst others) that I, the said William
Wain, by an instrument in writing under my hand and seal. should. par-
ticularly describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Wain, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawing hereunto annexed, and to the
letters and figures marked thereon (that is to say) :-
:-
This Invention relates to a novel construction of screw propeller, the blades
of which may be adjusted from the interior of the vessel to which the pro-
peller is applied. In the accompanying Drawing, Fig. 1 represents in sectional
elevation a screw propeller constructed according to my Invention, and attached
to the propeller shaft; Fig. 2 is a similar section, drawn on an enlarged scale;
and Fig. 3 is an elevation of the inner end of the propeller shaft and the
apparatus connected therewith, for giving an axial motion to the blades of
the propeller. a, a, is the boss of the propeller, cast in one piece, with an
opening through it, to receive the stems 6 of a pair of propeller blades c,
which are capable of being set to any required angle to suit the run of the
vessel. The gearing for effecting this adjustment is contained within the
'boss a, and is therefore not liable to injury or disarrangement. These stems
are set in conical bushes d, made in two halves, and bolted to the boss a, and,
by the inner edge of the bushes bearing against-a shoulder on their respective
'stems, they will hold the blades securely in their place, while at the same time
they afford a ready means of tightening up the stems in their sockets when
they have worked loose by wear.
The stems at their inner ends (see the enlarged view, Fig. 2,) lock into each
other when, as shewn in the Drawing, but one pair of blades is employed,
and by this means the strain or leverage upon one blade is counteracted by
the resistance offered by the other, so that the tendency of the blades to work
loose in their sockets is greatly diminished. I do not, however, confine myself
to the use of two blades, as any required number may be employed, the boss
being cast with a number of radial sockets corresponding to the number of
stems it is intended to receive. The stem of each blade is- provided with.a

page_text: ring of bevil teeth e, into which a pinion f takes, for turning the blades and
setting them at any required angle. This pinion f bas its bearing in the
propeller boss a, a suitably shaped recess being formed for its reception; and it
is provided with a square socket, into which takes the squared end of a shaft g,
that passes out through the stern of the vessel, to which the propeller is fitted,
and is employed for adjusting the blades to the required angle. The rear or
inner end of the shaft g bears against an elastic cushion of india-rubber, and
by that means it is pressed forward into the socket of the pinion f, and at the
same time causes that pinion to work in close contact with the bevil teeth e.
The propeller boss is provided with journals a*, a*, which are carried by
suitable bearings as usual. The propeller receives its motion from a hollow
shaft h, through which the shaft 9 passes, and in which that shaft has its
bearings. In the propeller boss a square socket is formed, to receive the
squared end of the shaft h, which projects out at the stern of the vessel.
The other or inner end of the shaft h is connected in any convenient manner
to the driving shaft * of the engine. This mode of connecting the propeller
with its driving and adjusting shafts will greatly facilitate their disconnection,
when such is required.
The inner end of the adjusting shaft g is feathered to receive a worm
wheel i, which fits into a recess formed for it in the end of the shaft h.
Gearing into the worm wheel i is a worm k, carried by a spindle j, which has
its bearings in the flange of the hollow shaft 7, as shewn best in the end view,
Fig. 3. By means of a key or winch handle k*, applied to either end of the
spindle j, rotary motion is given to the worm, which, taking into the worm
wheel, will turn the shaft g, and thus impart an axial motion to the pinion f;
but as this pinion is in gear with the rings of teeth e, e, on the stems of the
propeller blades, these blades will at the same time be caused to turn in their
sockets, and assume any required angle with respect to the driving shaft. In
order to unship the propeller, the shafts 9 and h are drawn back into the
vessel until they are clear of the boss of the propeller; the propeller may
be then unshipped in the usual manner. As in some cases it may be found
desirable to shorten this sliding movement of the shafts as much as possible,
I propose to give the adjusting shaft g an independent sliding motion. This
may be effected by providing in the abutting end of the driving shaft h* a
recess, to receive the end of the shaft g, and forming upon the shaft ý a
circular rack, into which gears a pinion carried by the hollow shaft. When,
therefore, this pinion is turned, the shaft g may be slidden backward, until its
outer end is drawn within the hollow shaft h. The two shafts may then be
drawn back together free of the propeller boss.

page_text: For the purpose of ascertaining the angle at which the blades are standing at
any given time, it may be found convenient to employ an index apparatus,
which shall receive its motion from the spindle j, and thereby determine the
amount of axial motion that has been imparted to the adjusting shaft.
Having now set forth the nature of my Invention of "Improvements in the
Construction of Screw Propellers," and explained the manner of carrying the
same into effect, I wish it to be understood that under the above in part recited
Letters Patent I claim,―
First, forming in one piece the boss of screw propellers, the blades of which
are adjusted by mechanism contained in the boss.
Secondly, the means berein described for securing the propeller blades in
their sockets, and of diminishing the tendency of the blades to work loose
therein.
And, thirdly, I claim the means herein described for setting the propeller
blades at any required angle.
In witness whereof, I, the said William Wain, have hereunto set my
hand and seal, the Twenty-seventh day of March, in the year of our
Lord One thousand eight hundred and fifty-five.
Witness,
N. E. TUXEN,
Captain, Danish Royal Navy,
Copenhagen.
W. WAIN. (L.B.)