Year: 1887

page_text: Date of Application, 20th Aug., 1887
Complete Left, 6th Apr., 1888
Complete Accepted, 11th May 1888
I, ISIDORE ESKELL CLIFFORD, of 8 Grosvenor Street, Grosvenor Square, in the
County of Middlesex, Surgeon-Dentist, do hereby declare the nature of said Invention,
to be as follows:-
:-
My Invention relates to an improved construction of shaft for screw propellers, and
other purposes, and it has for its object to construct the shaft in such a manner that
great strength is obtained for the same; the chance of fracture is avoided, and the
possibility of quickly repairing a shaft, whether employed for a screw propeller, or for
other purpose is provided for.
In the shafts now constructed for, say, screw propellers, it is impossible to ascertain
whether any flaw exists in the same, notwithstanding that the greatest care is taken
in their manufacture, and in case of fracture much time is lost in repairing the shaft,
or in substituting a new one; in some cases this is even impossible until the vessel
arrives in port.
I obviate all these inconveniences by means of my improved, but simple, construction
of shaft which is constructed of a suitable number of tubes or tubular pieces fitted
one within or over the other, but not welded together, as this would be liable to form
a solid mass or body which would defeat the purposes of my invention. The tubes
are, by preference, of the same thickness throughout and are retained in place by
being forced one into or over the other although, by preference, they do not terminate
in the same vertical line with one another. These tubes are secured for attachment to
the engine in any suitable manner.
A shaft so constructed will be found to possess greater strength than one made in a
solid piece, or in solid pieces.
Now, in case of injury from any cause arising to any one or more of these tubes,
the propeller will still be able to be worked with the remaining sound tubes, or it will
only be necessary to withdraw said injured tube, or tubes, and to substitute a sound
one, or sound ones, therefor, a spare number of which can always be carried on board
the vessel.
Although I have described my invention as applied to a screw propeller shaft, it may
be applied to the shafting of machinery generally.
D: L
CA 1007
ERNEST DE PASS, Fel. Inst. P.A.,
68, Fleet Street, London,
Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improved Construction of Shaft for Screw Propellers and other
Purposes.
I, ISIDORE ESKELL CLIFFORD, of 8 Grosvenor Street, Grosvenor Square, in the
County of Middlesex, Surgeon-Dentist, 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 (reference being had to the accom-
panying drawings and to the letters and figures marked thereon) that is to say:—
My Invention relates to an improved construction of shaft for screw-propellers and
other purposes, and it has for its object to construct the shaft in such a manner that
the chance of fracture is avoided and the possibility of quickly repairing a shaft whether
employed for a screw propeller, or for other purpose, is provided for.
In the shafts now constructed for, say, screw propellers it is impossible to ascertain
whether any flaw exists in the same notwithstanding that the greatest care is taken in
their manufacture, and in case of fracture inuch time is lost in repairing the shaft, or
in substituting a new one; in some cases this is even impossible until the vessel arrives
in port.
I obviate all these inconveniences by means of my improved, but simple, construction
of shaft, as about to be described with reference to the accompanying drawings in
which Fig. 1 is a longitudinal section and Fig. 2 a transverse section of a screw
propeller shaft constructed according to my invention.
In carrying out my Invention the shaft instead of being constructed as heretofore
in one solid piece or forging, or in more than one piece flanged and bolted together is
constructed of a suitable number of tubes or tubular pieces fitted one within or over
the other, but not welded together, as this would be liable to form a solid mass or
body which would defeat the purposes of my invention. In the figures shewn in the
drawings the shaft is constructed or built up of say three tubes a, b, c. All these tubes
are by preference of the same thickness throughout and are retained in place by being
forced one into or over the other although, by preference, they do not terminate in the
same vertical line with one another. At one end they are secured to a stepped plug
forming a plate & which is connected with the engine, and on the other end the screw
propeller is mounted in any suitable manner. The innermost tube a is first fitted on
and is then retained in place on the innermost step of the plate by screw bolts, then
the second tube b is fitted on and retained in like manner, and finally the third tube c.
Or these tubes may be secured for attachment to the engine in any other suitable
manner.
A shaft so constructed will be found to possess greater strength than one made in a
solid piece, or in solid pieces.
Now in case of injury from any cause arising to any one or more of these tubes the
propeller will still be able to be worked with the remaining sound tubes, or it will only
be necessary to withdraw said injured tube or tubes and to substitute a sound one or

page_text: sound ones therefor, a spare number of which can always be carried on board the
vessel.
Although I have described and shewn my invention as applied to a screw propeller
shaft it may be applied to the shafting of machinery generally.
Having now particularly described and ascertained the nature of my said
invention and the manner in which the same is to be performed I declare that what
I claim is :-
A shaft for screw propellers, and other machinery, consisting of a suitable number
of tubes fitted or built up one within or over the other substantially as herein described
and for the purposes set forth.