Improvements in Propellers for Vessels.
Year: 1895

page_text: Date of Application (in United Kingdom), 4th Nov., 1895
Complete Specification Left, 4th Nov., 1895-Accepted, 9th May, 1896
Improvements in Propellers for Vessels.
I DANIEL SAMUEL DARK, of 150 E 38th Street in the City of New York,.
United States of America, Cutter 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 :-
My invention relates to paddle-wheels for ships, and has for its object to produce.
a highly efficient propelling agent for vessels.
Heretofore screw propellers and the ordinary side and stern paddle wheels have
been used almost exclusively for the propulsion of vessels. These modes of
propulsion were defective for a variety of reasons, and their various defects are
well-known and recognized. My invention seeks to obviate the defects of
existing propellers and consists in a submerged paddle-wheel of a construction
which will be hereinafter pointed out and claimed, and which is preferably located.
amidships.
In the drawing, forming part hereof, -
Figure 1 is a fragmentary midship section of a vessel provided with a paddle-
wheel constructed according to my invention;
Figure 2 is an enlarged detail view of one of the paddle-blades; and
Figures 3 and 4 are detail views of the two members or blades of one of the
buckets.
In the drawing, A is the hull of a vessel and B the paddle-box. C is the paddle
wheel shaft preferably located amidships and at such a distance below the water
line L. W. L. as to maintain the wheel D constantly submerged under normal
conditions. Secured to the shaft C by means of suitable connections (omitted for
the purpose of clearer illustration) are the annular members E of the paddle-wheel,.
which annular members are held rigidly together by means of transverse rails F..
Mounted upon the rails F are the buckets G consisting of curved blades H which
are brought together to a point at I and are braced in the rear by brackets J and
braces K. These blades it will be observed are of greater depth where they meet.
at the point I and may be variously secured to the paddle-wheel, as for instance by
means of the holes e in the flanges h thereof. The blades H are in the plane of
the axis of the wheel at their points of greatest divergence from their junction
point I, and thence gradually incline away from the said plane in the direction of
the said point I, so that each blade presents a progressively warped surface whose
inclination to the axis constantly varies, which has the effect of securing great
efficiency of action. It will be quite obvious that a rotation of the paddle wheel
will cause the vessel to be propelled, the direction of rotation being preferably in
the direction in which the points I are turned. It will likewise be found that my

page_text: paddle-wheel possesses numerous advantages, some of which I will proceed to
enumerate. The wheel being below the water line and within the hull, insures
greater safety for ships of war, in that there is little liability of their being carried
away by projectiles, waves, collisions or docking. Again, the wheel being always
in the water, the racing of engines is reduced to a minimum, and owing to the
construction of the blades, a reversal of the engines will be more promptly
responded to by the ship than heretofore. Again, the wheels being amidships, the
reversing of one wheel on one side will turn the ship in a narrower compass than
heretofore.
It will be quite obvious that the construction may be varied without departing
from the spirit of my invention, hence I would have it understood that I do not
mean to limit myself to the construction and arrangement shown.
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 :-
In a submerged paddle-wheel, the combination of annular members E and
buckets carried thereby, the said buckets consisting of the curved blades H
angularly disposed to one another and joined at the point I, the said blades being
disposed radially to the axis of the annule at their points of greatest divergence
from their junction point I, and thence gradually inclined away from the radial
line in the direction of the said point I, so that the blades present progressively
warped surfaces whose inclination to the axis of the annula continually departs
from the radial line of the annulæ, substantially as described.
Dated this 2nd day of November 1895.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.