Improvements in or connected with Screw Propeller and other similar Shafts.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in or connected with Screw Propeller and other
similar Shafts.
We, CHARLES JOHN COPELAND and GEORGE HEPBURN, both of 11, Redcross
Street, Liverpool, in the County of Lancaster, Consulting Engineers, do hereby
declare the nature of this invention to be as follows:-
-
This invention has reference primarily to the tail shafts of screw propellers of
ships, and our invention will be described chiefly as applied to or in connection
with such shafts: the invention, however, also relates and is applicable to other
relative shafting including crank shafts-working under torsion, and subject
to similar or equivalent action and stresses. The object of the present invention
is, mainly, to provide or to make shafting which shall not be so liable to breakage
or to become dangerous for further use, after a certain length of use and wear;
or to develop flaws or cracks (which generally run in a direction transverse to
the action of the shaft): but which shall be able to be used as tail shafts of screw
propellers with their peculiar torsional stresses and vibrations, which they are
subjected to in their ordinary working, without any such liability of damage,
weakening, or becoming dangerous.
In a shaft of iron or steel-according to this invention, the grain or fibre of the
Fetal does not run transversely to the direction of the stress, that is the torsional
stress of the shaft, which is transversely to its axis, but substantially in the same
direction as the stress and it is made by first rolling or winding a bar or bars of
ron into a spiral coil with the convolutions of the spirals separated a certain
distance apart. Then this spiral bar or coil, when at a high temperature, is
placed in a mould, and the core within the coils, and the spaces between the con-
volution of it, are filled with molten steel or other metal poured into the mould;
with the result that a union or fusion between the molten steel and the solid hot
coil takes place, so that the two parts of which the article-namely the shaft-is
composed, becomes practically one solid piece of metal.
According to a modification, the coil of iron (or steel) while highly heated is
placed in a mould, and molten cast iron or other metal is run into it so as to fill
up the core within the coil and the spaces between the convolutions. In this
case, the cast metal will not make a union with or fuse onto the solid coil, and
will thus constitute a core having upon it spiral grooves, in which the spiral con-
volutions of the wrought coil will lie.
.

page_text: Improvements in or connected with Screw Propeller and other
similar Shafts.
We, CHARLES JOHN COPELAND and GEORGE HEPBURN, both of 11, Redcross
Street, Liverpool, in the County of Lancaster, Consulting Engineers, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly, described and ascertained in and by the following
statement:-
This invention has reference, primarily, to the tail shafts of screw propellers of
ships, and our invention will be described chiefly as applied to, or in connection
with such shafts: the invention, however, also relates, and is applicable, to other
rotative shafting including crank shafts-working under torsion, and subject
to similar or equivalent action and stresses. The object of the present invention
is, mainly, to provide or to make shafting which shall not be so liable to breakage,
or to become dangerous for further use, after a certain length of use and wear;
or to develop flaws or cracks (which generally run in a direction transversely to
the action of the shaft); but which shall be able to be used as tail shafts of screw
propellers, with their peculiar torsional stresses and vibrations which they are
subjected to in their ordinary working, without any such liability of damage,
weakening, or becoming dangerous.
In a shaft of iron or steel-according to this invention, the grain or fibre of the
metal does not run transversely to the direction of the stress, that is, the torsional
stress of the shaft, which is transversely to its axis, but substantially in the same
direction as the stress; and it is made by first rolling or winding a bar or bars of
iron into a spiral coil, with the convolutions of the spirals separated a certain
distance apart. Then this spiral bar or coil, when at a high temperature, is
placed in a mould, and the core within the coil, and the spaces between the con-
volutions of it, are filled with molten steel, or other metal, poured into the mould;
with the result that a union or fusion between the molten steel and the solid hot
coil takes place, so that the two parts of which the article-namely, the shaft is
composed, becomes practically one solid piece of metal.
According to a modification, the coil of iron (or steel) while highly heated is
placed in a mould, and molten cast iron or other metal is run into it, so as to fill
up the core within the coil and the spaces between the convolutions.
In this
casc, the cast metal will not make a union with, or fuse onto the solid coil, and
will thus constitute a core having upon it spiral grooves, in which the spiral con-
volutions of the wrought coil will lie.
In the drawings, illustrating this invention, Figure 1 shews a finished tail shaft,
of a ship's propeller shaft, according to the invention; and Figures 2 a
trate, in detail, the coil used in the manufacture of the shaft, and a longitudinal
section of completed shaft. Figure 4 shews a crank shaft according to this
invention.
The coiled bar constituting the primary element or portion of the shaft, is
designated a, and this is in the open spiral form as shewn in Figure 2. The
section of the bar from which this coil is made will be rectangular, so that in its
coiled state it will present a section larger on the inner than the outer face, as
shewn in Figure 3; the object being to get a keying effect or construction between
the shaft or coil and the core. The core of the shaft is designated b, and it is
produced, as above described, by running into the core of the coil, and the spaces
between the convolutions, molten steel, preferably; and in doing this, the spiral
coil is first heated to a high temperature, and then placed in a mould, and the

page_text: molten metal poured into the mould; the result being a union or fusion between
the molten steel and the coil, so that these two parts of which the article, viz., the
shaft is composed, become one.
In Figure 1, the dotted lines and dotted sectional parts a, represent the iron
coil; and the full lined section parts the core. e represents the journal liners on
the shaft, on which it revolves in its bearings.
In the crank shaft shewn in Figure 4, the parts marked o are of the construction
of shaft above described, and the webs or cheeks p, and the flanges q, are respec-
tively shrunk and forged upon these parts o.
As a modification, instead of the shaft consisting, when complete, of a combina-
tion of a coil, and cast steel, and forming practically one structure, the coil of
wrought iron or steel, while in a highly heated state within the mould, has run
or cast into it, cast iron. By this, the core and spaces between the convolutions of
the coil are fitted with this metal, but no fusion of the two takes place.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
1. The herein described improved propeller or like shaft, namely, a shaft com-
prised of a wrought iron or steel open coil, and a core within the centre of the coil
and between the convolutions thereof, of cast metal, and made by first coiling a
bar into an open coil, and then while at a high heat, and within a mould, running
in molten metal; substantially as set forth.
2. The shaft made up or comprised of the coil part a, and the core parts b, as
set forth with reference to and shewn in the drawings.
L
L
1900
CHEESBROUGH & ROYSTON,
Applicant's Patent Agents, 15, Water Street, Liverpool.