Steam Ship Propeller.
Year: 1892

page_text: Date of Application, 26th Feb., 1892
Complete Specification Left; 17th May, 1892-Accepted, 11th June, 1892
i
PROVISIONAL SPECIFICATION.
Steam Ship Propeller.
WILLIAM CAMPBELL No. 2 Battery Terrace, Oban in the County of Argyle
Scotland of no occupation do hereby declare the nature of this invention to be as
follows: --
A propeller consisting of an ordinary boss with two or more blades, springing
perpendicularly from it, and revolving in the same plane. The blades are perfectly
straight, having no twist, and their planes are each at an angle of from 45° to 50°
to the axes of the boss. The edges of the blades thus cut the water at a corre-
sponding angle the angle to be determined according as a rough or smooth pitch
is desired.
The length and breadth of the blades to be in accordance with the size and
horse power of the steamer.
Dand 41 f Waha 1905
WILLIAM CAMPBELL.
COMPLETE SPECIFICATION.
Steam Ship Propeller.
I, WILLIAM CAMPBELL, 2, Battery Terrace, Oban, in the County of Argyle,
Scotland, of no occupation, 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 :-
The nature of my invention is a propeller for steam ships and other navigable
vessels, consisting of an ordinary boss with two or more blades springing from it
perpendicularly, and revolving each in the same planes.
The blades are perfectly straight having no twist (or screw), and their planes are
cach at an angle of from 45° to 50° and upwards-(the angle to be determined
according as a rough or smooth pitch is desired)-to the axis of the boss. The
edges of the blades thus cut the water at a corresponding angle.
The length and breadth of the blades shall be in accordance with the size and
horse power of the steamer or vessel.
A fine edge to the blades is to be obtained by rounding off the thickness from
the non-thrusting surface, thus leaving the thrusting surface perfectly flat.
In order that the foregoing statements as to the nature and construction of this
invention may be clearly understood, I hereunto append a sheet of explanatory
drawings by which a three-bladed and a two-bladed propeller are delineated by way
of example.
Fig. I is a front elevation with three blades B, B, B at an angle of 54° to the
axis of the boss A.
Fig. 2 is a plan showing the blade C D at an angle of 50° to the axis of the
boss, and also showing the slightly rounded non-thrusting, and the flat thrusting
surface of the blade.
Fig. 3 is a side elevation of a two-bladed propeller with the blades at an angle
of 54° to the axis of the boss.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the saine is to be performed, I declare that what I
claim is:
1. A propeller for steam ships and other navigable vessels, consisting of two or

page_text: more straight blades having no twist (or screw) on an ordinary boss as hereinbefore
described.
2. A steam ship propeller having straight blades without twist (or screw), and
each blade having its thrusting surface perfectly flat as hereinbefore described and
illustrated in the accompanying drawings.
Dated thin 14th din of Ma 1900
WILLIAM CAMPBELL.