IMPROVEMENTS IN SCREW PROPELLERS
Year: 1860

page_text: LETTERS PATENT to James Brickhill, of Saint Leonard's Road, Bromley,
and James Noble, of York Street East, Stepney, both in the County of
Middlesex, Engineers, for the Invention of "IMPROVEMENTS IN SCREW
PROPELLERS."
PROVISIONAL SPECIFICATION left by the said James Brickhill and
James Noble, at the Office of the Commissioners of Patents, with their
Petition, on the 3rd May 1860.
We, JAMES BRICKHILL, of Saint Leonard's Road, Bromley, and JAMES NOBLE,
of York Street East, Stepney, both in the County of Middlesex, Engineers, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN SCREW
PROPELLERS," to be as follows:-
The object of this Invention is to set the blades of screw propellers to any
required pitch or angle, according to the power of the engine, or as may other-
wise be required, in a more simple and efficient manner than heretofore, and is
effected as follows:-I propose passing a vertical shaft from the deck down to
one end of the boss of the propeller; this shaft has a bevelled wheel affixed
thereto, working into another similar wheel secured to a horizontal screw,
which passes through the boss fore and aft; the ends of the blades revolvo in
the boss, and have affixed to them worm wheels, which exactly fit the thread
of the horizontal screw; thus it is evident that as motion is imparted to the
vertical shaft from the deck, the blades will be moved in opposite directions to

page_text: the pitch or angle required; when the shaft is not required to be used it can
be raised with its wheel out of gear by means of a screw collar on deck to any
required height.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Brickhill and James Noble in the Great Seal Patent
Office on the 3rd November 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
BRICKHILL, of Saint Leonard's Road, Bromley, and JAMES NOBLE, of York
Street East, Stepney, both in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of May, in the year of our Lord One
thousand eight hundred and sixty, in the twenty-third year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto us, the said
James Brickhill and James Noble, Her special licence that we, the said
James Brickhill and James Noble, our executors, administrators, and assigns,
or such others as we, the said James Brickhill and James Noble, our
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 SCREW PRO-
PELLERS," upon the condition (amongst others) that we, the said James
Brickhill and James Noble, our executors or administrators, by an instrument
in writing under our or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the samo 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 James Brickhill, do hereby declare
the nature of our said 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 :-
The object of this Invention is to set the blades of screw propellers to any
required pitch or angle, according to the power of the engine, or as may
otherwise be required, in a more simple and efficient manner than here-
toforc.

page_text: proceed to describe the best means we are acquainted with for carrying the
same into practical effect, reference being had to the illustrative Sheet of
Drawings hereto annexed, and to the numeral figures and letters of reference
marked thereon respectively, as follows:-
DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a side view of the Invention, shewn partly in section; Fig. 2, a.
top plan view; and Fig. 3, cross section of the boss of the propeller, takeri
through the line A, B, (Fig. 2.) Similar letters of reference denoto corre
sponding parts in so far as such parts appear or can be seen at each of such
said Figures respectively.
At Fig. I will be seen a vertical shaft a passed through the deck of the
vessel and down to the "aft" end of the boss 6 of the propeller; this shaft has
a horizontal bevelled wheel c attached thereto, working in a vertical bevelled
wheel d, secured to a horizontal screw e, passing longitudinally through the boss.
The ends of the blades revolve in the boss b, and have affixed to them worm
wheels ff, the thread of which exactly fits that on the horizontal screw e. Thus
it will appear evident that as motion is imparted from the deck to the vertical
shaft a the blades will be moved in opposite directions to the pitch or angle
required; when the shaft is not required to be used for the aforesaid purpose
it can be raised slightly by means of a screw collar g on the deck, for the
purpose of disengaging the wheels c and d, or throwing them out of gear.
The blades having been set to the required pitch are kept in position not
only by the pressure of the worm wheels on the horizontal screw, but in order
also to case the strain of the blades a quadrant h is attached to the base of
cach blade, and secured to the flat sides of the boss by a screw i, which is
loosened or tightened by a spanner or square-ended rod passing through a
guide tube in the deck to ensure its dropping on or into the screw i. By this
arrangement the whole screw, with boss, wheels and bushes, can be drawn or
slid up the framej on to the deck for repairs or otherwise.
Having now described the nature of our said Invention of "Improvements
in Screw Propellers," and the manner in which the same is to be performed,
we would remark, in conclusion, that we do not confine or restrict ourselves
to the precise details shewn in the annexed Drawing, and herein-before referred
to, as many slight modifications and variations may be made therein without
in any way departing from the principle of our Invention; but what we claim
as our Invention, intended to be secured to us by the herein in part recited
Letters Patent, is, the improved method of setting the blades of screw pro-

page_text: pellers to any required pitch, in the manner shewn in the accompanying Sheet
of illustrative Drawings, and herein fully described, for the purposes set
forth.
In witness whereof, I, the said James Brickhill, have hereunto set my
hand and seal, this Thirty-first day of October, in the year of our Lord
One thousand eight hundred and sixty.
JAMES BRICKHILL. (L.S.)
Witness.
L. J. WETHERELL,
Clerk to Messrs. Prince & Co., Patent Agents,
4, Trafalgar Square,
Charing Cross.