IMPROVEMENTS IN AGRADARNE BAD PROPELLING SHIPS AND OTHER VESSELS
Year: 1862

page_text: LETTERS PATENT to William Carwood, of Stepney, in the County of
Middlesex, Engineer, William Boaz, of Bromley, in the same County,
Engineer, and Charles Colwell, of Belvedere Place, Southwark, in the
County of Surrey, Gentleman, for the Invention of "IMPROVEMENTS IN
AGRADARNE BAD PROPELLING SHIPS AND OTHER VESSELS"
PROVISIONAL SPECIFICATION left by the said William Carwood, William
Boaz, and Charles Colwell at the Office of the Commissioners of Patents
with their Petition on the 22nd August 1862.
I, WILLIAM CARWOOD, of Stepney, in the County of Middlesex, Engineer,
WILLIAM BOAZ, of Bromley, in the same County, Engineer, and CHARLES
COLWELL, of Belvedere Place, Southwark, in the County of Surrey, Gentleman,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
APPARATUS FOR PROPELLING SHIPS AND OTHER VESSELS," to be as follows:-
We construct propelling apparatus in such manner that we produce centri-
petal action, by which the water is, so to speak, gathered towards the vessel
and then expelled in a direction in a line with or parallel to the propeller
shaft. We set on a shaft or axis blades or vanes, shaped like sections of a
sphere or other rounded figure, and presenting their concavities in the oppo-
site direction to that in which the vessel is to be propelled; they are so set
that if the full figure, spherical or otherwise, of which they are sections, were
completed, and if they were sufficiently near to each other on the shaft, those

page_text: spheres or full figures would intersect; their rounded edges form sections of
screws of enlarging pitch. They thus exert a confluent action on the water,
producing centripetal force, which gathers the water towards the axis and
expels it as described, contrary to what has hitherto been done by screw pro-
pellers which have exerted a centrifugal action. The blades or vanes are most
frequently on a boss, but loose thereon, being maintained in proper working
position by pins, stops, or abutments, against which they are kept by the
pressure of the water. The boss is not a fixture on the shaft, but is held
thereon preferably by a clutch. The vanes may be brought fore and aft of
the shaft, or placed at the desired angle in respect thereof, and the boss may
be reversed on the shaft, so that the position of the vanes or blades, and hence
the direction of motion of the vessel may be reversed. The propeller may be
feathered and the vessel may be steered by these arrangements. When
employed in propelling, the blades frequently lie transversely to and obliquely
on the shaft,
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Carwood, William Boaz, and Charles Colwell in
the Great Seal Patent Office on the 21st February 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
CARWOOD, of Stepney, in the County of Middlesex, Engineer, WILLIAM BOAZ,
of Bromley, in the same County, Engineer, and CHARLES COLWELL, formerly of
Belvedere Place, Southwark, in the County of Surrey, and now of South
Town, in the County of Suffolk, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-second day of August, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did for Herself, Her heirs and successors, give and grant unto us,
the said William Carwood, William Boaz, and Charles Colwell, Her special
licence that we, the said William Carwood, William Boaz, and Charles
Colwell, our executors, administrators, and assigns, or such others as we,
the said William Carwood, William Boaz, and Charles Colwell, our exe-
cutors, 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 APPARATUS FOR PRO-

page_text: PELLING SHIPS AND OTHER VESSELS," upon the condition (amongst others) that
we, the said William Carwood, William Boaz, and Charles Colwell, our execu-
tors or administrators, by an instrument in writing under our or their hands
aud seals, or under the hand and seal of one of us or them, should particularly
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 we, the said William Carwood, William Boaz, and
Charles Colwell, do hereby declare the nature of the said Invention, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement thereof, reference being had to
the accompanying Drawings, and' to the letters and figures marked thereon,
that is to say:-
We construct propelling apparatus in such manner that we produce centri-
petal action, by which the water is, so to speak, gathered inward and then
expelled in the direction of or in a line with or parallel to the propeller shaft ;
for this purpose we set on a propeller shaft blades or vanes shaped like sections
or portions of a hollow sphere, and presenting their concavities in the opposite
direction to that in which the vessel is to be propelled; they are so set that
if the full spberical figure, of which they are sections, were completed, those
spheres or full figures would intersect, their outermost edges are of increasing
pitch. They thus exert a confluent action on the water and produce centri-
petal force, which gathers the water towards the axis, the water being expelled
as described, contrary to what has hitherto been done by screw propellers
which have exerted a centrifugal action. The blades or vanes may be adjustable
on a boss, so as to be set at the desired angle in respect of the shaft, and so that
they, and hence the vessel's direction, may be reversed; in this case the boss is
not a fixture on the shaft, but is loose thereon, being connected with it by a
clutch. The blades most frequently lie transversely to and obliquely on the
shaft.
We proceed, with reference to the accompanying Drawings, particularly to
describe what we believe the best means of carrying our Invention into
effect.
Figures 1 to 10, inclusively, relate to a propeller with reversible blades;
Figure 1 is an elevation, Figure 2 longitudinal section, Figure 3 outer face
view, Figure 4 side view, & Figure 5 top view of the propeller; Figures
6, 7, 8, and 9 are elevations of the clutches; and Figure 10 of the blade
gearing.

page_text: A is the propeller shaft worked and supported in the ordinary manner;
B is a hollow boss on the shaft A; this boss is not a fixture to the shaft, but
is connected with it, as herein-after described, and it terminates at the inner
end in a conical flange b; C, C, are the propeller blades. Each blade is a
section of a sphere, that is, a portion of the surface of a hollow sphere. We
mostly prefer that each blade shall be a twelfth part of such sphere; a small
portion c¹ of each blade is straightened and set parallel with the shaft, and at
these parts c' the blades are connected with the boss; d, d, are toothed bevilled
wheels, cast on the parts c', c¹; these wheels are within the boss into which
they pass through holes in its sides. The axes d' of the wheels d are fixed to
and project from the boss B, and on them are screwed nuts or screw caps ƒ to
keep the blades on the boss. The blades are set on the boss, as before
described, their convex surfaces being towards the ship or vessel, and their
concave surfaces towards the opposite direction to that in which the ship or
vessel is to be propelled. G is a coupling or boss keyed fast on the shaft A;
the inner face of this coupling is within the boss (in which is an opening to
receive it); this inner face has in it four slots g, and to it is bolted a toothed
bevilled wheel H by bolts h passing through the slots g, g. The wheel H is
in gear with the wheels d, d. The wheels d, d, and H are equal, and have
strong coarse teeth. The pitch of the blades is varied by slacking the bolts
and turning one of the blades to the required pitch or angle, the other blade
being in gear with it will assume the same pitch or angle, and the blades will
be held thereat by bolting up the wheel H in the slots. I is a coupling or
boss fast on the shaft A, and having a clutch (Figure 6) formed on its face
consisting of two stops or projections i, j; these stops or projections are solid
concentric arcs opposite each other, and struck from radii of different length.
The longer arc i is close to the edge of the boss I, and the shorter arc j close
to the hole of the boss through which the shaft A passes. The arc i is at its
outer edge one quarter of the circumference of the boss I, and the arc j is at
its inner edge one quarter of the circumference of the shaft A. Corresponding
arc-shaped stops or projections k, l, Figure 7, are formed on the inside face b³
of the boss B, the arc k corresponding to the arc i, and the arc 1 to the arc j.
When the boss B and shaft A are working together the stop i abuts against the
stop k, and the stop j against the stop l; m, Figure 8, is a clutch sliding on
feathers p upon the coupling I; the clutch is worked by a forked lever P, and
is in gear with a corresponding clutch 2, Figure 9, formed on the face of the
flange b. The chief object of the clutches m, n, is to prevent back lash, and
to assist in keeping the blades at their pitch. O is a tube or cylindrical shield
bolted to and projecting from the vessel around the clutch m. Q is a friction

page_text: band or break loose on the boss B, and connected to the clutch m by arms s,
so that it may be worked by the lever P. The friction band is guided by its
trunnions q working in guide ways r in the tube O. When the break Q is
free on the boss B, and when the clutch i, j, is in gear with the clutch k, l,
and the clutch m with the clutch n, the boss B and blades C, C, will revolve
with the shaft A; but when the shaft is to be reversed, the lever P is worked
to bring the break Q taut against the flange b, the same action of the lever P
throws the clutch m out of gear with the clutch n; the shaft is then reversed,
and will turn free of the boss B for a half turn, the stops i, j, slipping free of
the stops k, l, while the wheel I will turn the wheels d, d, half round, and so
reverse the blades or cause them to present their concavities in an opposite
direction to that in which they were presented before; at the end of the half
turn of the shaft A the stops i, j, k, l, will come together, and at the same
time the attendant will work the lever P, so as to loose the break Q from the
flange b, and throw the clutch m into gear with the clutch n, so 'that the boss B
and blades C will turn with the shaft.
Although we have described the use of a loose boss combined with blades
shaped like sections of a sphere, we wish it to be understood that the employ-
ment of a boss loose on a shaft for the purpose of allowing the reversing of
propeller blades may be applied for that purpose to propellers other than those
in which the blades or vanes are shaped like sections or portions of a sphere.
Figures 11, 12, and 13, refer to a modification of the propeller in which the
blades C³, C, are not reversible, but are a fixture on a boss B¹ fixed on the
propeller shaft A'. The blades, though differing in outline from those in
Figure 1, are on the same principle, each blade being a section or portion of a
sphere. Figure 11 is a side view, Figure 12 face view, and Figure 13 edge
view.
,, is a flange or lip on the outermost edge of the convex side of the
blade; its object is to lessen the tendency to centrifugal action, and so assist
the motion astern when the shaft is reversed.
The arrangement and combination of parts described in reference to
Figures 1 to 10, inclusively, by means whereof blades may be reversed, is
applicable also to the reversing of propeller blades other than those shaped like
portions of a sphere.
Having now described the nature of our said Invention, and in what manner
the same may be performed, we wish it to be understood that in respect of our
blade, shaped like a portion or section of a sphere, we do not restrict ourselves
to any particular outline or form of edge of such blade, as the same may be
varied without departing from the principle of constructing the blade as a

page_text: portion or section of a hollow sphere. Also we do not restrict ourselves to any
particular portion, dimension, or proportion of sphere, nor to any precise pitch
or angle of the blades with respect to the shaft; and we declare that what
we claim as of our said Invention is,―
First, constructing a propeller blade or vane of the form of a section or
portion of a hollow sphere.
Second, the employment on a propeller shaft of a boss loose thereon for the
purpose of allowing propeller blades to be reversed.
Third, the general arrangement and combination of parts herein-before
described, by means whereof propeller blades may be reversed.
In witness whereof, we, the said William Carwood, William Boaz, and
Charles Colwell, have, hereunto set our hands and seals, this Twentieth
day of February, in the year of our Lord One thousand eight hundred
and sixty-three.
Witness,
M. HENRY, Patent Agent,
84, Fleet Street,
London.
W. CARWOOD. (L.S.)
W. BOAZ.
(L.S.)
C. COLWELL.
(L.S.)