Improvements in Propelling Apparatus for Ships or Vessels.
Year: 1894

page_text: Date of Application, 3rd Oct., 1894
Complete Specification Left, 3rd Aug., 1895-Accepted, 28th Sept., 1895.
PROVISIONAL SPECIFICATION;
Improvements in Propelling Apparatus for Ships or Vessels.
I THOMAS ARMSTRONG of No. 30 Lime Street in the City of London, Gentleman,
do hereby declare the nature of this invention to be as follows:-
This invention relates to a propeller blade..
The object of my invention is to produce a rotary propeller formed of one, two
or more blades of novel design, and possessing greater power than propellers in
ordinary use.
Each blade is exactly or approximately formed by a union or combination of
2 segments.or sections of a tube or pipe which may be of such proportions or
diameter as may be suitable for producing a propeller that may be adapted to the
size or class of vessel requiring propulsion. One segment or section of tube
represents the forward or leading half or part of my blade and the other segment
or section the following or after portion of the blade. Propellers may be made,
cast or forged in one piece or in sections. The several blades may also be
detachable or shifting and fastened to any boss shaft or other appliance by any
suitable or workable means and in grooves or otherwise. The blades may be
attached in any position, angle, inclination or degree as may be deemed expedient
or advantageous. My propeller is capable of moving ships or vessels abead, astern
or otherwise.
In further description the forward or leading portion of the blade is exactly
or approximately the section of a cylinder or tube which may be tapering or
otherwise.
The after or following part of the blade is reversely curved and exactly or
approximately the same in form as the forward portion of the blade.
Dated this 3rd October 1801
I, THOMAS ARMSTRONG, of 30 Lime Street, in the City of London, Gentleman;
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:-
This invention relates to propelling,apparatus for ships or vessels and has for its
object an improved rotary propeller furnished with one two or more blades of
novel design and possessing greater power than propeller blades constructed as
heretofore.
According to my invention each blade is formed by the union or combination of
two segments or sections of a hollow cylinder,, or of two curved segments or sections
which approximate to those of a cylinder. The two parts of the blade are curved
in reverse directions and may be united directly or by an intermediate piece which
may be straight or curved. The curved segments or sections may be of the same
or of different areas. They are proportioned and their peripheries are shaped to
suit the vessel to which tho propeller is to be applied.

page_text: Keterring to the accompanying drawing
Figure 1 is a rear elevation of a propeller blade constructed according to my
invention.
Figures 2, 3, 4, 5, 6 and 7 are sections of the blade taken on the lines, 2, 2; 3, 3;
4,4; 5, 5; 6, 6; and 7, 7 respectively.
Figure 8 is a side elevation of another propeller blade constructed according to
my invention.
"
Figures 9, 10, 11, 12 and 13 are sections of the blade taken on the lines 9, 9 ;
10, 10; 11, 11; 12, 12 and 13, 13 of Figure 8..
A is the propeller blade, B is the hub.
The blade A in Figure 1 is made up of two reversely curved sections or segments
of a hollow cylinder united along the line 6, 6. The character of the blade is clearly
indicated by the several sections Figures 2 to 7.
The blade shown in. Figure 8 consists of reversely curved sections or segments
of a cylinder, (one on the left of the dotted line marked a, and the other on the
right of the dotted line marked y) united by a triangular shaped piece of blade
enclosed between the dotted lines, y which piece may be straight or curved in
transverse section. The shape and relative size of the central uniting piece
may be varied. The shape of this blade is clearly indicated by the sections
Figures 9 to 13.
In my improved blade one segment or section of cylinder represents the forward
or leading half or part of the blade and the other section the following or after
part of the blade.
The propeller may be made by casting or forging the same in one piece or in
two or more sections. The several blades may be detachable from the hub or
boss, and may be rigidly fixed thereto or adjustable thereon by any suitable means
in grooves or otherwise.
The blades may be attached in any position and at
any angle inclination or degree as may be deemed expedient or advantageous
and they may be of any or varying thickness and strengthened at the point of
attachment as desired.
My improved propeller is capable of efficiently moving ships or vessels ahead
and astern or otherwise.
In a modification of my invention instead of making the blade from sections
or segments of a cylinder, I make it from sections or segments of a tapering tube
or hollow.cone.
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 -
1. A propeller blade formed by uniting a segment of a hollow cylinder or of
a tapering tube or cone or of a surface approximating to the cylindrical, with
a like segment but having a curvature in the reverse direction, substantially as
described.
2. A propeller blade formed of two segments of a hollow cylinder or of an
approximate cylinder or of a taper tube or conc united by a centre piece which may
be straight or curved, the said segments being curved in reverse, directions, and
having the same or different areas, substantially as described.
T 1805.
1 Dated this 2nd day of July
VUTO
THOMAS ARMSTRONG.
Haseltine, Lake & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.