Improvements in or relating to Stern Tubes.
Year: 1899

page_text: Date of Application, 10th Mar.,
1899
Complete Specification Left, 30th Nov., 1899-Accepted, 27th Jan., 1900
Improvements in or relating to Stern Tubes.
We, ALEXANDER ELLIOTT, Engineer, and ELLIOTT AND GARROOD LIMITED,
Engineers, of Ingate Iron Works, Beccles, in the County of Suffolk, do hereby
declare the nature of this invention to be as follows:-
This invention relates to stern tubes and although it may be applied to various
kinds of vessels it is especially suitable for fishing smacks where economy of
space is of the greatest importance, and we will describe it as so applied. It is
found in practice that the outer portion of the tail shaft just forward of the
propeller boss wears rapidly or is eaten away by the action of sea water and that
it is of importance to be able to renew the bearing and protect the shaft; for
this purpose we adopt at the outer end of the stern tube the following construction.
The outer end of the stern tube proper terminates at any convenient point and
upon this end of the stern tube we secure a removable portion or section which
may be conveniently fastened on to the stern tube by splitting a portion of it
and clamping it by means of lugs and bolts-other means however of securing
the removable section may be employed.
Upon the outer end of the tail shaft is secured a sleeve or tube which takes the
wear and is so arranged that if desired it can be drawn on to the shaft by the boss
of the propeller which is forced on by the nut at the end of the shaft; this is a
particularly convenient way of protecting the shaft and renewing the wearing
parts thereof. The removable section of the stern tube may be entirely or partly
lined with white metal or other suitable bearing metal, the upper portion being
preferably left empty to receive lubricant which can be applied by a suitable
opening or may be filled in before the section is placed in position-or other
means may be employed for the lubrication.
To facilitate the insertion and removal of the tail shaft into the stern tube which
is a difficult operation where the space in the engine room is very confined we
adopt the following construction. The inner end of the stern tube is closed by a
cap which is preferably placed obliquely so that when it is removed it leaves a
large opening to the tube; this cap or cover may also form a portion of the
stuffing box.
For a convenient distance the upper portion of the stern tube is enlarged
obliquely so that the cover being removed and the shaft drawn inwards as far as
it can go in a straight line it can then be raised to a sufficient extent to clear any
obstruction such as parts of the engine or the like which without this accommo-
dation in the tube would prevent the shaft from being withdrawn. The precise
shape, position and proportions of the accommodation thus provided in the stern
tube may be varied according to circumstances and the arrangement or disposition
of the cover would be varied accordingly. For example, the inner end of the
tube might retain its circular form but be conical or trumpet-mouthed so as to

page_text: accomplish the same object although usually it would be convenient to tilt the
shaft vertically it will be appreciated that this may be done horizontally or other-
wise if preferred.
The inner end of the tube may be arranged as a bearing for the shaft if desired.
BOULT & WADE,
Agents for the Applicants.
Improvements in or relating to Stern Túbes.
We, ALEXANDER ELLIOTT, Engineer, and ELLIOTT AND GARROOD LIMITED,
Engineers, of Ingate Iron Works, Beccles, in the County of Suffolk, 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 relates to stern tubes and although it may be applied to various
kinds of vessels it is especially suitable for fishing smacks where economy of
space is of the greatest importance, and we will describe it as so applied. It is
found in practice that the outer portion of the tail shaft just forward of the
propeller boss wears rapidly or is eaten away by the action of sea water and that
it is of importance to be able to renew the bearing and protect the shaft; for
this purpose we adopt at the outer end of the stern tube the following construction.
The outer end of the stern tube proper terminates at any convenient point and
upon this end of the stern tube we secure a removable portion or section which
may be conveniently fastened on to the stern tube by splitting a portion of it
and clamping it by means of lugs and bolts-other means however of securing
the removable section may be employed.
Upon the outer end of the tail-shaft is secured a sleeve or tube which takes
the wear and is so arranged that if desired it can be driven home on to the shaft
by the boss of the propeller which is forced on by the nut at the end of the shaft;
this is a particularly convenient way of protecting the shaft and renewing the
wearing parts thereof. The removable section of the stern tube may be entirely
or partly lined with white metal or other suitable bearing metal, the upper
portion being preferably left empty to receive lubricant which can be applied
by a suitable opening or may be filled in before the section is placed in position―
or other means may be employed for the lubrication.
To facilitate the insertion and removal of the tail-shaft into the stern tube
which is a difficult operation where the space in the engine room is very confined
we adopt the following construction. The inner end of the stern tube is closed
by a cap which is preferably placed obliquely so that when it is removed it
leaves a large opening in the tube; this cap or cover may also form a portion of
the stuffing box.
For a convenient distance the upper portion of the stern tube is enlarged
obliquely so that the cover being removed and the shaft drawn inwards as far as
it can go in a straight line it can then be raised to a sufficient extent to clear
any obstruction such as parts of the engine or the like which without this
accommodation in the tube would prevent the shaft from being withdrawn. The
precise shape, position and proportions of the accommodation thus provided in the
stern tube may be varied according to circumstances and the arrangement or
disposition of the cover would be varied accordingly. For example, the inner
end of the tube might retain its circular form but be conical or trumpet-mouthed
so as to accomplish the same object although usually it would be convenient

page_text: to tilt the shaft vertically it will be appreciated that this may be done horizontally
or otherwise if preferred.
The inner end of the tube may be arranged as a bearing for the shaft if desired.
In the accompanying drawings
Figure 1 is a longitudinal central section of one construction of stern tube
according to this invention.
Figure 2 is a side elevation of the inner end of the same.
Figure 3 is an end elevation looking in the direction of the arrow in Figure 2,
and
Figures 4 and 5 are transverse sections on the lines 4-4 and 5-5 respectively
of Figure 1.
Like letters indicate like parts throughout the drawings.
A is a tail-shaft, the outer end of which is provided with a renewable sleeve
or tube B placed upon the shaft from the propeller end. The sleeve B is furnished
with an internal flange B' abutting against a shoulder A¹ upon the shaft A, and
may be driven home upon the shaft by the boss C of the propeller which is forced
on in the usual way by means of a nut working upon a screw-thread on the end of
the shaft. A portion only of the propeller boss C is shown in Figure 1.
D) is a stern tube having a removable outer section E which is split for a
portion of its length as at El and is secured to the stern tube D by bolts which are
passed through holes E3 in lugs E. The removable section E is partially lined
with bearing metal as at F, this lining forming a bearing in which the sleeve B
on the shaft A revolves.
The inner end of the stern tube D is enlarged as at 11 to facilitate the removal
of the shaft and an oblique opening is made in the enlarged portion, the opening
being closed by a cap 13 secured by means of bolts and nuts D³. In the example
illustrated the cap 12 forms part of a stuffing-box through which the shaft A
passes, I being the gland of the stuffing-box operated in the usual way by
bolts D5.
It is to be understood that various alterations may be made in the construction
of the improved stern tubes without departing from the spirit of this invention.
For example, the removable section may be attached in any convenient way and
not necessarily by being split and fastened with bolts. Again the opening in
the tube to facilitate the insertion or removal of the shaft need not be always
oblique but may be of any form suitable for the purpose, the removable cap or
cover being, of course, shaped to suit the opening. In some cases it suffices to
make an oblique opening in the inner end of the stern tube without enlarging
that end in the manner described.
Having now particularly described and ascertained the nature of our said in-
vention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. A stern tube having a removable outer section.
2. The combination with a stern tube of a removable outer section split for a
portion of its length and secured upon the stern tube by lugs and bolts substan-
tially as described.
3. The combination with a propeller shaft of a renewable sleeve or tube such
as B forming a tail bearing and driven home on the shaft from the propeller end
substantially as described.
4. The combination with a propeller shaft having a renewable sleeve or tube
of a removable stern tube section.
5. A stern tube having a removable cap at its inner end for the purpose
described.
6. A. stern tube having an oblique opening at its inner end for the purpose
described.
7. A stern tube having an oblique opening at its inner end normally closed by

page_text: 8. A stern tube having its inner end enlarged to facilitate the removal of the
shaft substantially as described.
9. The complete stern tube substantially as described or illustrated in the
accompanying drawings.
Dated this 24th day of November 1800
ALEXANDER ELLIOTT
ELLIOTT & GARROOD LIMITED.
WM. ELLIOTT,
W. J. ELLIOTT.
}
Directors.
Boult, Wade & Kilburn,
Agents for the Applicants.