IMPROVE- MENTS IN PROPELLERS POR SHIPS OR OTHER NAVIGABLE VESSELS
Year: 1870

page_text: LETTERS PATENT to William Tyrer, of Brook Lawn, Birkdale, South-
port, in the County of Lancaster, for the Invention of "IMPROVE-
MENTS IN PROPELLERS POR SHIPS OR OTHER NAVIGABLE VESSELS.”
Sealed the 19th August 1870, and dated the 4th March 1870.
PROVISIONAL SPECIFICATION left by the said William Tyrer at the
Office of the Commissioners of Patents, with his Petition, on the
4th March 1870.
I, WILLIAM TYRER, of Brook Lawn, Birkdale, Southport, in the
5 County of Lancaster, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN PROPELLERS FOR SHIPS OR OTHER NAVIGABLE VESSELS," to
be as follows :-
-
The object of my Invention of improvements in propellers for ships or
other navigable vessels is to construct propellers so as to give a great
O amount of speed and power together with great facility for manoeuvring
or steering the vessels to which they are applied; also the use of this
propeller dispenses with the necessity for great draught of water aft as is

page_text: usual in screw ships; also great facilities for adjustment and repair, inas-
much as the blades can be altered and set to any required pitch, or can
be repaired, if necessary, without having occasion to go into a graving
dock, or having to beach.
Propellers constructed according to this Invention consist of two
bosses or centres from which spring any suitable number of radial arms
or blades. These radial arms or blades are set on their respective bosses
with a pitch, the one boss or centre having its arms or blades set to a
right-handed pitch, and the other boss or centre having its arms or
blades set to a left-handed pitch. These centres or bosses are keyed or
otherwise attached on to shafts in this wise:-A horizontal shaft running
from the engines or "propelling power to the after end of the ship, just
above or clear of the water line, carries one boss or centre, say with its
radial arms or blades right-handed. This shaft is hollow or bored so as
to admit of a second shaft passing through its centre. To the end of
this second shaft is keyed or otherwise attached a second boss or centre
having its radial arms or blades with a left-handed pitch, These shafts
are caused (when the vessel is going ahead or astern) to revolve in
opposite directions, the same action taking place with their respective
propellers. In case it is required to turn the vessel the shafts with their
respective propellers are caused to revolve in the same direction, thereby
causing the vessel's stern to come round to port or starboard in the
respective way in which the shafts revolve. These propellers may be
placed within an aperture formed in the stern of the vessel, or they may
project outside of the after end of the vessel altogether and be covered
over by a propeller box or other suitable provision. The shafts carrying
the propellers being above the level of the water line it will be obvious
that the propellers are easy of access for adjustment or repair. The
propellers revolve having only the arms on the lower or under side of
the centre submerged; that is, on the upper side of the centre the arms
or blades are clear of the water, and on the under side of the centre
the arms or blades are submerged. From the large size of the propeller
it is apparent that it will not be necessary for the engines to travel as
fast as is the case in ordinary screw vessels to enable these propellers
to give a good result in speed. In lieu of the hollow horizontal shaft
these propellers may be fitted as follows:-The first, or say right handed,
propeller is keyed on to an ordinary horizontal solid shaft. The second,
or left handed propeller, is keyed or fixed on to a short shaft, which works
between a small horizontal beam or other suitable provision and the

page_text: stern post of the vessel. The bosses or centres of the propellers are
fitted with vertical pinions or toothed wheels, the forward propeller
having the pinion or toothed wheel at the after side of its boss, and the
after propeller having the pinion or toothed wheel on the forward side
of its boss. These pinions or toothed wheels gear into a horizontal
toothed wheel fixed above them, and working between the before.
mentioned horizontal beam and the deck of the vessel. When the first
or forward propeller revolves it will cause, by means of its pinion, this
horizontal toothed wheel to revolve also, and it in its turn gearing into
the pinion or toothed wheel on the after propeller will cause it to revolve
only in a contrary direction to the forward propeller. These propellers
are, as in the first case, on the same centre, and their bosses or centre.
clear of the water line of the vessel allowing only their under arms or
blades to be submerged. The propellers may be actuated or worked
entirely by means of the horizontal geared wheel before mentioned ; but
in neither of these latter cases are the advantages gained as perfect as when
using the hollow shaft, as it is obvious that the propellers when driven by
this means (the horizontal toothed wheel) cannot be made to beneficially
effect the steering or manoeuvring of the ship, but it still retains the
other advantages-power, speed, accessability for repair and adjustment.
In some cases, where deemed expedient, I fit a fixed ring round
each boss or centre having an excentric slot or groove in which
the radial arms or blades of the propellers work, thereby causing the
blades or arms to feather on edge upon leaving the water and resume
their pitch upon entering, thus obviating the loss of power entailed by
the blades tending to throw up the water as they emerge and lessening
the strain thrown upon the blades of the propellers. These propellers
are especially adapted for vessels having light draught and built for the
navigation of shallow waters, also are especially adapted for use in canals
as they give less "wash" than propellers of the ordinary description.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Tyrer in the Great Seal Patent Office on
the 3rd September 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
5 TYRER, of Brook Lawn, Birkdale, Southport, in the County of Lancaster,
send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of March, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Tyrer, Her special licence that I,
the said William Tyrer, my executors, administrators, and assigns, or
such others as I, the said William Tyrer, 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 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 PROPELLERS FOR SHIPS
OR OTHER NAVIGABLE VESSELS," upon the condition (amongst others) that
I, the said William Tyrer, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and scals,
should particularly describe and ascertain the nature of the said Inven-
tion, 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 Tyrer, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement :-
The object of my Invention of improvements in propellers for ships
or other navigable vessels is to construct propellers so as to give a great
amount of speed and power together with great facility for manoeuvring
or steering the vessels to which they are applied; also the use of this
propeller dispenses with. the necessity for great draught of water aft, as
is usual in screw ships; also great facility for adjustment and repair,
inasmuch as the blades can be altered and set to any required pitch,
or can be repaired, if necessary, without having occasion to go into a
graving dock, or having to beach.
Propellers constructed according to this Invention consist of two
bosses or centres from which spring any suitable number of radial arms
or blades. These radial arms or blades are set on their respective
bosses with a pitch, the one boss or centre having its arms or blades set
to a right-handed pitch, and the other boss or centre having its arms or
blades set to a left-handed pitch. These centres or bosses are keyed

page_text: or otherwise attached on to shafts in this wise:-A horizontal shaft
running from the engines or propelling power to the after end of the
ship, just above or clear of the water line, carries one boss or centre,
say with its radial arms or blades right handed. This shaft is hollow or
bored so as to admit of a second shaft passing through its centre. To
the end of this second shaft is keyed or otherwise attached a second
boss or centre having its radial arms or blades with a left-handed pitch.
These shafts are caused when the vessel is going ahead or astern to
revolve in opposite directions, the same action taking place with their
respective propellers. In case it is required to turn the vessel tho
shafts with their respective propellers are caused to revolve in the same
direction, thereby causing the vessel's stern to come round to port or
starboard in the respective way in which the shafts revolve, or a similar
effect may be obtained by merely stopping one propeller, although not
so efficiently. These propellers may be placed within an aperture
formed in the stern of the vessel, or they may project outside of the
after end of the vessel altogether and be covered over by a propeller
box or other suitable provision. The shafts carrying the propellers
being above the level of the water line it will be obvious that the
propellers are easy of access for adjustment or repair. The propellers
revolve having only the arms on the lower or under side of the centre
submerged; that is, on the upper side of the centre the arms or blades
are clear of the water, and on the under side of the centre the arms or
blades are submerged. From the large size of the propeller it is
apparent that it will not be necessary for the engines to travel as fast
as is the case in ordinary screw vessels to enable these propellers to
give a good result in speed. In lieu of the hollow horizontal shaft
these propellers may be fitted as follows:-The first, or say right-handed,
propeller is keyed on to an ordinary horizontal solid shaft. The second,
or left-handed propeller, is keyed or fixed on to a short shaft, which
works between a small horizontal beam or other suitable provision and
the stern post of the vessel. The bosses or centres of the propellers are
fitted with vertical pinions or toothed wheels, the forward propeller
having the pinion or toothed wheel at the after side of its boss, and the
after propeller having the pinion or toothed wheel on the forward side
of its boss. These pinions or toothed wheels gear into a horizontal
toothed wheel fixed above them, and working between the before-
mentioned horizontal beam and the deck of the vessel. When the first
or forward propeller revolves it will cause, by means of its pinion, this

page_text: horizontal toothed wheel to revolve also, and it in its turn gearing into
the pinion or toothed wheel on the after propeller will cause it to
revolve, only in a contrary direction to the forward propeller. These
propellers are, as in the first case, on the same centre, and their bosses
or centre clear of the water line of the vessel allowing only their under 5
arms or blades to be submerged. The propellers may be actuated or
worked entirely by means of the horizontal geared wheel beforo
mentioned; but in neither of these latter cases are the advantages
gained as perfect as when using the hollow shaft, as it is obvious that
the propellers when driven by this means (the horizontal toothed wheel) 1
cannot be made to beneficially effect the stcering or manoeuvring of
the ship, but it still retains the other advantages-power, speed, access-
ability for repair and adjustment. The propellers may be worked
and actuated by means of a vertical shaft extending through tho
aperture in the stern and carrying a horizontal toothed wheel, the tecth of 1
which gear into horizontal teeth projecting from wheels keyed or
attached on the aft side of the boss of the forward propeller and on the
forward side of the boss of the after propeller. The teeth of these
wheels are so arranged as to gear simultaneously into the teeth of the
horizontal wheel when in one position for going ahead, but are so 2
arranged that if the horizontal wheel is lowered it will throw one
vertical wheel out of gear, and if raised it will throw the other vertical
wheel out of gear, so being enabled to drive one or the other propeller
separately, and being thus advantageous for steering purposes.
In some cases, where deemed expedient, I fit a fixed ring round each 2
boss or centre having an excentric slot or groove in which the radial
arms or blades of the propellers work, thereby causing the blades or
arms to feather on edge upon leaving the water and resume their pitch
upon entering, thus obviating the loss of power entailed by the blades
tending to throw up the water as they emerge and lessening the strain 3
thrown upon the blades of the propeller. These propellers are especially
adapted for vessels having light draught and built for the navigation of
shallow waters, also are especially adapted for use in canals as they give
less "wash" than propellers of the ordinary description.
The before going being the nature and object of my Invention, I will g
now proceed to describe more in detail the manner in which the same is
to be or may be performed or carried into practical effect, and in order
that the same may be more clearly and readily understood I have here-

page_text: unto annexed a Sheet of Drawings illustrative thereof, and have
marked them with figures and letters of reference corresponding with
those in the following explanation. Like letters and figures are used to
denote similar parts.
Figure 1 is a portion of the after end of a vessel fitted with my pro-
pellers working on a hollow and solid shaft, and having their bosses
clear of the water line; Figure 2, an end view of same; Figure 3 is the
portion of the after end of a vessel fitted with my propeller, in this case
driven by gearing; Figure 4 illustrates a modification of gearing
suitable for driving my propeller so that both can be worked together
or separately; Figure 5 shows my propeller working with the blades
coming into a box or casing on the deck of the vessel; Figure 6, end
view of same; Figures 7, 8 and 9 show arrangements of propellers
adapted to different draughts.
A, after end of ship; B, boss of forward propeller; O, boss of after
propeller; D, radial arms or blades which are set on bosses B and C at
a pitch or angle to the shaft. The angle of forty-five degrees will I
consider be found most advantageous, but that can be altered or adjusted
if necessary, the blades D being set, say, on boss B to a right-handed
pitch or angle, and the blades D on the boss C to a left-handed pitch
or angle or vice versa; E, hollow shaft carrying boss B; F, solid shaft
carrying boss C; G, after bearing; H, space or aperture in the stern of
the vessel for propellers to work in; K, water line; L, strengthening or
stiffening rings connecting blades of propeller; M, box or casing
covering propeller; N (Figure 3), vertical geared wheel on forward
propeller; O vertical geared wheel on after propeller; P, horizontal
geared wheel working into wheels N and O; R, vertical shaft carrying
horizontal wheel P; S, supporting beam; T (Figure 3), shaft of forward
propeller; V, shaft of after propeller. The following is the action and
working of this propeller :-The propeller B revolves, say, to the right
hand and the propeller C revolves in an opposite direction, say to the
left hand, thus causing the vessel to go staight ahead. If one propeller
is stopped the vessel will turn to that hand to which the blades of the
propeller still working are set, and if both propellers revolve the same
way the vessel will turn round on her own centre. Propellers aro
driven by any suitable machinery connected to shafts E and F. In
the case of Figure 3 propellers can be driven either with an ordinary
propeller shaft T, driving propeller N, which is geared to propeller V

page_text: revolving in an opposite direction, or they can be driven by vertical
shaft R worked from the deck by steam, winch, or other driving means.
In the case of Figure 4; S, vertical shaft; T, horizontal toothed wheel; U,
vertical toothed wheel on boss of forward propeller; V, vertical toothed
wheel on boss of after propeller. It will be seen on reference when
the horizontal wheel T is in position it gears into the teeth of wheels
U and V. When it is raised it is out of gear with wheel V and in
gear with wheel U. Again when it is lowered it is out of gear with
wheel U, and in gear with wheel V, thus enabling propellers to be
worked together or separately.
Having now described and ascertained the nature and purposes of this
my Invention, together with the manner in which the same is to be
or may be carried out, I wish it to be understood that I do not limit
myself to the shape of the propellers as regards the blades or bosses,
nor do I limit myself to the exact position of the bosses with regard
to the water line, or to the pitch of the blades, or to the several pro-
portions or relative dimensions of the various parts of the construction,
as it will be readily seen that the same may be considerably varied
without departing from my Invention, but what I claim as new and
my Invention is, the adaptation of two propellers working one before 2
the other, their respective blades being of right and left handed pitch
and revolving in opposite directions, and having only half the number of
their blades immersed at one time, substantially in the manner and for
the purposes herein-before described and set forth.
In witness whereof, I, the said William Tyror, have hereunto set 2
my hand and seal, this First day of September, in the year of
our Lord One thousand eight hundred and seventy.
Witness,
FREDERICK F. CHEESBROUGH,
of 43, Castle Street,
Liverpool.
WILLIAM (L.S.) TYRER.