Reciprocating Propellers for Floating Vessels.
Year: 1893

page_text: Date of Application, 11th Feb., 1893-Accepted, 18th Mar., 1893
COMPLETE SPECIFICATION.
Reciprocating Propellers for Floating Vessels.
I, CHARLES FREDERICK OSBORNE, of 103 Loop Street, Cape Town, Civil
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:―
My invention relates to the construction and means of operating reciprocating
propellers for floating vessels, as I shall describe referring to the accompanying
drawings, which shew two modes in which a propeller according to my invention
may be worked.
Fig. 1 is a side view partly in section, Fig. 2 is a sectional plan, and Fig. 3 is
an end view of the stern part of the vessel, the propeller of which is worked
directly from two engine cylinders.
Figs. 4, 5 and 6 are similar views, partly in section, of the arrangement of
propeller worked from a single crank.
Referring first to Figs. 1, 2 and 3, two engines A A', which may work together
as a compound engine, by means of slotted crossheads or otherwise work cranks at
right angles to each other on a countershaft B, carrying eccentrics connected to
the slide valves of the two engines, which thus have the strokes of their pistons
timed as if the whole of their power was applied to work a main shaft having
cranks at right angles.
The piston rods C C of the two engines are continued down through stuffing
boxes D D into a space provided in the dead wood, the one rod C being rigidly
connected to an arm E projecting forward and the other rod C¹ being connected
through a jointed link to an arm E' projecting backward from a boss F, from
which two blades G project laterally one on each side of the deadwood. These
blades being moved up and down, with varying inclinations, make such displacement
of the water in which they move that the reaction operates in propelling the
vessel.
The boss F and its arms E E' as well as the rods C C¹ are preferably enclosed
within a casing, the boss F working freely in slots cut in the side plates of the
casing.
As shewn in Figs. 4, 5 and 6 the propeller blades G project on each side from a
boss F which is rigidly attached to a connecting rod H.
This connecting rod is linked to a crank K on a shaft L which is worked by a
pair of engines, arranged as shewn or otherwise.
The crank K, connecting rod H and boss F are all enclosed in a casing, through
stuffing boxes D D' in the sides of which the shaft L passes. The boss F may
work in straight guide slots in the side plates of the casing, or it may be, as
shewn, linked to a radius R and pass freely through the side slots without being
guided by them.
The radius may extend aft, as indicated at R', the enclosed space in the dead
wood being suitably shaped, to admit of its movement.
The propeller blades G, being in this case rigidly attached to the connecting
rod H, are variously inclined as they ascend and descend in conformity with the
varying inclinations of the connecting rod as its head travels along the circular
path of the crank. The displacement of the water by the blades so moving is
such that the reaction operates to propel the vessel.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that I make no
general claim to a propeller consisting of a blade caused to reciprocate by

page_text: connecting its ends to cranks at right angles to each other on a shaft parallel to
the line of propulsion, but I declare that what I claim is :-
1. A propeller for a floating vessel consisting of a pair of blades projecting on
each side of the dead wood from a boss which, by its connection to a pair of arms
and rods reciprocating as from cranks at right angles to one another, receives up
and down motion and also, during its strokes, such variations of inclination that
the blades having the same motion and varying inclination are reacted on by the
water which they displace and operate to propel, substantially as herein described.
2. A propeller for a floating vessel consisting of a pair of blades projecting on
each side of the deadwood from a boss which, by its rigid attachment to a
connecting rod linked to a crauk, receives up and down motion and also, during
its strokes, such variations of inclination that the blades having the same motion
and varying inclination are reacted on by the water which they displace and
operate to propel, substantially as described.
Dated this 11th day of February 1893.
ABEL & IMKAY,
Agents for the Applicant.