Improvements in Propellers for Ships and Boats.
Year: 1896

page_text: Date of Application, 20th Mar., 1896
Complete Specification Left, 16th Dec., 1896-Accepted, 23rd Jan., 1897
Improvements in Propellers for Ships and Boats.
I, JAMES PARIS, of 24 South Albion Street, in the County of Glasgow, North
Britain, Engineer, do hereby declare the nature of this invention to be as follows,
that is to say:-
My said invention has for its object to obtain an improved action and increased
efficiency with a certain kind of submerged propeller, combined with other practical
advantages.
In carrying out my invention I apply two of my improved propellers, one on
each side of the stern or other part of a ship or boat. Each propeller consists of
two blades fixed on a shaft in a diametrical position, and it works in a casing of a
segmental cylindrical form if the blades are rectangular, but which can be shaped
to suit other forms of blade. The shaft may be horizontal, vertical, or inclined,
and driven by a steam engine or other motor; or in the case of a boat it may be
driven by manually actuated gearing. The casing can be turned upon the shaft,
and its position determines the direction in which the propelling action takes effect.
In the position of the casing for going ahead, the blades moving sternwards in the
bottom of their course, about a quarter of the circumferential part of the casing is
open to the water, the open part extending from the lowest point to about the
level of the shaft on the after side. In passing through the open part each blade
in succession acts backwards on the water, and in addition to the direct propelling
action thereby effected carries water into and round the interior of the casing and
expels it forcibly in a rearward direction as it again approaches the open part of
the casing.
Means are provided for shifting round the casing so as to propel astern or ahead,
with or without altering the direction of rotation of the shaft; and the casing
may be set so as to propel from its under or upper side as desired, if the shaft is
horizontal. With a vertical shaft the casing will always be set to propel from its
outer side. The propellers on the two sides of a ship may have their casings
placed differently so as to steer or turn the ship, either in conjunction with the
rudder or in its absence.
Dated this Nineteenth day of March 1896.
EDMUND HUNT,
Applicant's Agent.
COMPLETE SPECIFICATION.
Improvements in Propellers for Ships and Boats.
I, JAMES PARIS, of 24 South Albion Street, in the County of Glasgow, North
Britain, Engineer, 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, that is to say :-
My said invention has for its object to obtain an improved action and increased

page_text: efficiency with a certain kind of submerged propeller, combined with other practical
advantages.
In carrying out my invention I apply on each side or other part of a ship or
boat a propeller consisting of two blades fixed diametrically on a shaft, and working
in a casing made with a segmental circumferential opening and turnable about
the propeller shaft which is driven manually or by a motor.
And in order that my said invention and the manner of performing the same
may be properly understood I hereunto append a sheet of explanatory drawings
to be hereinafter referred to, and showing some modifications of my improved
propeller.
Figures, 1, and 2, of the drawings are vertical sections, as at right angles to each
other, of one modification of my improved propeller. Figures, 3, and 4, are similar
views of a second modification, and Figures, 5, and 6, are similar views of a third
modification of my improved propeller. In these drawings the same reference
letters are used to mark the same or like parts wherever they are repeated.
In carrying out my invention I apply two of my improved propellers, one on
each side of the stern or other part of a ship or boat. Each propeller consists (as
shown in Figures, 1, and 2) of two blades, A, fixed on a shaft, B, in a diametrical
position, and it works in a casing, C, which is of a segmental cylindrical form
when the blades are rectangular. The shaft, B, is horizontal but it might be
vertical or inclined; and it is driven by a steam engine or other motor; or in the
case of a boat it may be driven by manually actuated gearing. The shaft, B, is
carried by an external bearing, D, and by an internal bearing or bearings (not
shown) and the shaft passes through a stuffing box, E, fixed internally to the skin
of the ship or boat. The casing, C, is fitted to the shaft, B, with gland bearings, G,
so that it can be turned upon the shaft, and its position determines the direction in
which the propelling action takes effect. In the position of the casing, C, for
going ahead, the blades, A, moving sternwards in the bottom of their course (that
is in the direction of the arrow, H) about a quarter, J, of the circumferential part
of the casing is open to the water, the open part extending from the lowest point, K,
to a point, F, at or about the level of the shaft on the after side.
In passing
through the open part J, each blade, A, in succession acts on the water, and in
addition to the direct propelling action thereby effected, carries water into and
round the interior of the casing, C, and expels it forcibly in a rearward direction
as it again approaches the open part of the casing. Lateral openings, Q, are
provided in the casing, C, to facilitate the entrance of the water to the interior of
the casing.
On the shaft, B, there is a sleeve, L, which is fixed to the casing, C, and this
sleeve has applied to it, within the ship any convenient mechanism for shifting
round the casing suitably for propelling astern or ahead, with or without altering
the direction of rotation of the shaft. The dotted lines, R, indicate the position of
the open part, J, of the casing, C, for propelling astern. In some cases, the
casing may be arranged for propelling in one direction from one side and in the
opposite direction from the other side without reversing the shaft.
When the shaft, B, is vertical and the propeller at the side of the vessel the
casing, C, will be set to propel from its outer side. The propellers on the two
sides of a ship may have their casings placed differently so as to steer or turn the
ship, either with or without the rudder.
In the modification shown in Figures, 3, and 4, the propeller as shown in
Figures, 1, and 2, is as it were divided, the blades, A, of one part being placed at
right angles to those of the other part. The casing, C, in this case may be divided
by a vertical partition, indicated by dotted lines, M, which passes between each
pair of blades. The open part, J, of the casing, C, is about a third of the perimeter
of the casing.
In the modification shown in Figures, 5, and 6, the propeller is made with two
blades, A, fixed in a diametrical position on the shaft, A, by arms, N, connected

page_text: by annular strengthening disks, P. The propeller blades, A, are shown rounded
at their outer ends and the casing, C, is made to suit them.
Any variation in detail shown in any figure may be applied in modifications.
otherwise constructed as shown in other figures.
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:-
A submerged propeller consisting of a pair of diametrically placed blades fixed
to a rotating shaft, or two or more pairs of such diametrically placed blades fixed
to longitudinally different parts of the shaft, combined with a casing having a
segmental opening and movable to alter the direction of propulsion, the parts.
being arranged and operating substantially as herein before described.
Dated this Fifteenth day of December 1896.
EDMUND HUNT,
Applicant's Agent..