Year: 1886

page_text: Date of Application, 22nd Feb., 1886.
Complete Left, 20th Dec., 1886.
Complete Accepted, 28th Jan., 1887.
I WILLIAM LOE BOVYER, of No. 510 Sacramento Street, in the City and County of
San Francisco, State of California, one of the United States of America, Carpenter
and Builder, do hereby declare the nature of this invention to be as follows:-
My Invention relates to improvements in propellers for ships and vessels and the
improvements contained in and forming the subject matter of the invention consist in
producing and constructing a propelling device with a single continuous blade or
acting surface in the form of a helix after the manner and upon the principle of
construction as herein set forth, and also in constructing a blade or acting surface
with two faces, of which one sets parallel with the actuating shaft and the other.
extends outwards radially from the forward or leading edge of the first mentioned one
and forms an angle with it as described and pointed out herein.
My improved propeller is produced by fixing a plate of metal in the form of a
continuous helix around a shaft by means of spokes or radial arms in such manner
that the inner edge of the helical blade stands at every point equidistant from the
shaft. The blade is of uniformn width and in length is made sufficient to produce
about one complete revolution about the shaft. Its face also sets at the same angle at
any point of cross section.
To the inner edge of this helical blade standing away from the shaft I fix a plate or
strip of metal of suitable width in such manner that it shall extend rearward and
make an angle with the principal plate or blade and shall stand also substantially
parallel with the line of the shaft. This plate as thus applied is employed for the
twofold purpose of giving strength and stiffness to the helical blade and of acting to
produce effective hold of the blade upon the water and prevent dispersion thereof from
the face of the blade; in the one case it enables a light blade to be employed with
safety, and in the other, it increases the working power of the propelling surface.
The helical blade is also made in some cases from a plate having a curved or concave
shape in cross section, for the same purpose, namely to prevent dispersion of the water

page_text: and bring the force to act more nearly in a fore and aft line. In a flat blade such
effect will result also from setting the face of the blade at an angle with the line of
the shaft and with the outer edge of the blade inclined to the rear. In this particular
form of the helical blade the projecting flange or surface on the inner edge constitutes
an important feature in securing efficient action of the propeller, and in the practical
application and use of my invention it is considered advisable to give this projecting
inner blade or face along the edge of the helical blade, a width of face about equal to
the distance from inner to outer edge of the radial blade projected on the axis of the
helix. Such surface will therefore be reduced in width in proportion as the helical
blade is brought to the perpendicular, in which last named position given to the blade
the projecting strip on the inner edge may be a rod or bar or simple angle plate
secured along the edge.

page_text: COMPLETE SPECIFICATION,
Improvements in Propellers for Ships and Vessels.
I WILLIAM LOE BOVYER of No. 510 Sacramento Street in the City and County of
San Francisco State of California one of the United States of America Carpenter
and Builder do hereby declare the nature of this invention and in what manner the
saine is to be performed, to be particularly described and ascertained in and by the
following statement :-
My invention relates to improvements in propellers for ships and vessels, and the
improvements contained in and forming the subject matter of the invention consist in
producing and constructing a propelling device with a single continuous blade or
acting surface in the form of a helix after the manner and upon the principle of con-
struction as herein set forth; and also in constructing a blade or acting surface with
two faces, of which one sets parallel with the actuating shaft and the other extends
outward radially from the forward or leading edge of the first mentioned one, and
forms an angle with it as described and pointed out herein.
My improved propeller is produced by fixing a plate of metal in the form of a
continuous helix around a shaft by means of spokes or radial arms in such manner
that the inner edge of the helical blade stands at every point equidistant from the
shaft. The blade is of uniform width, and in length is made sufficient to produce
about one complete revolution about the shaft. Its face also sets at the same angle at
any point of cross section.
To the inner edge of this helical blade standing away from the shaft I fix a plate or
strip of metal of suitable width in such manner that it shall extend rearwards and
make an angle with the principal plate or blade and shall stand also substantially
parallel with the line of the shaft. This plate as thus applied is employed for the
twofold purpose of giving strength and stiffness to the helical blade and of acting to
produce effective hold of the blade upon the water and prevent dispersion thereof
from the face of the blade; in the one case it enables a light blade to bo employed
with safety, and in the other, it increases the working power of the propelling
surface.
The helical blade is also made in some cases from a plate having a curved or
concave shape in cross section for the same purpose, namely, to prevent dispersion of
the water and bring the force to act more nearly in a fore and aft line.
In a flat blade such effect will result also from setting the face of the blade at an
angle with the line of the shaft and with the outer edge of the blade inclined to the
rear.
In this particular form of the helical blade the projecting flange or surface on
the inner edge constitutes an important feature in securing efficient action of the
propeller, and in the practical application and use of my invention it is considered
advisable to give this projecting inner blade or face along the edge of the helical
blade a width of face about equal to the distance from inner to outer edge of the
radial blade projected on the axis of the helix. Such surface will therefore be reduced
in width in proportion as the helical blade is brought to the perpendicular; in which
last named position given to the blade, the projecting strip on the inner edge may be
a rod or bar or simple angle-plate secured along the edge.

page_text: In the accompanying drawings :-
Figures 1 and 2 are perspective views of a propeller constructed according to my
invention with the face of its blade inclined to the rear and the inner edge thereof
turned backwards to stand substantially parallel with the shaft.
Figure 3 is a side elevation of the same.
Figures 4 and 5 are cross sections through two different forms of blades, one with
a flat face and the other concave.
Figure 6 represents a propeller having the face of the blade set perpendicular to the
shaft.
A. is the shaft; B. the helical blade and CC the radial supporting-arms.
B is the flange or projecting surface along the inner edge of the blade.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is
1. A propeller for vessels consisting of a spiral blade fixed around a shaft, as A, by
supports that leave the center open and having the inner edge next the shaft turned
backwards to stand at an angle with the acting surface of the blade substantially as
herein described.
2. In a propeller for vessels, a blade having its acting face formed of two surfaces
standing at a right angle or less than a right angle to each other and having one
surface substantially parallel with the line of the propeller shaft and the other surface
extending outwards perpendicular to or at an angle with such parallel surface
substantially as herein described.
3. A propeller for vessels having a spiral blade, as B, with a projecting flange or
surface as B on the inner edge and fixed to the propeller shaft by arms, as C, the
principal face of the blade being inclined to the axis and the face B* standing
substantially parallel with it.
For the Annlicant