Compensators for the Shrouds of Steamship Funnels.
Year: 1894

page_text: Date of Application, 9th Apr., 1894
Complete Specification Left, 29th Sept., 1894-Accepted, 10th Nov., 1894
PROVISIONAL SPECIFICATION.
Compensators for the Shrouds of Steamship Funnels.
We, JOHN LIST of 3 St: John's Park Blackheath in the County of Kent
Engineer, and ROBERT ANDREW MUNN of 11 Prince's Terrace Dowanhill
Glasgow in the County of Lanark, Engineer, do hereby declare the nature of this
invention to be as follows:-
:-
The object of this invention is to overcome the difficulty which has up to now
been experienced in keeping constantly in tension the shrouds of funnels on board
ship, from the fact that the height from the deck of the band on the funnel to
which the shrouds are attached varies with the temperature of the funnel due to
the condition of the fires. With the high funnels now generally in use, and more
particularly where the boilers are worked under forced draft, this variation of the
height due to the expansion and contraction of the metal of the funnel is
considerable and requires constant attention to be given to the adjusting screws or
lashings of the shrouds, while, if slackness in these be permitted when the vessel
is rolling considerable risk may be run from the funnel waying and breaking its
connections.
This invention consists in substituting for the usual tightening screw or lashing
a compensator arranged as follows-To the lower end of the shroud is attached
a single grooved sheave or pulley carrying below it an attachment for a flexible
wire rope. To the deck is attached another pulley carrying above it a smaller
guiding sheave, which has above it an attachment for the lower end of a spiral
steel spring which is used in tension. A flexible wire rope is attached below the
pulley on the shroud and is passed between the guiding sheave and the lower pulley
attached to the deck, then round this pulley and up over the pulley carried by the
shroud, the end being then made fast to the upper end of the spiral spring.
The lengths of the shroud and the compensator are so adjusted that the
initial tension on the spring when the funnel is cold is sufficient to prevent swaying
should the ship be lying at anchor with fires drawn and exposed to a swell which
causes rolling. The spring is so proportioned that the maximum expansion. of
the funnel due to forcing the fires does not put an undue load or extension
upon it.
Dated this Fifth day of April 1894.
JOHN LIST.
ROBERT A. MUNN.
COMPLETE SPECIFICATION.
Compensators for the Shrouds of Steamship Funnels.
We, JOHN LIST, of 3 St. John's Park, Blackheath, in the County of Kent,
Engineer, and ROBERT ANDREW MUNN, of 11 Princes Terrace, Dowanhill,
Glasgow, in the County of Lanark, 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:
The object of this invention is to overcome the difficulty heretofore,experienced
of keeping constantly in tension the shrouds of steamship funnels, and which
arises from the fact that the height from the deck of the band on the funnel to
which the shrouds are attached varies with the temperature of the funnel due to

page_text: the condition of the boiler fires. With the high funnels now generally in use,
and more particularly where the boilers are worked under forced draught, this
variation of the height, due to the expansion and contraction of the metal funnel,
is considerable, and requires constant attention to be given to the adjusting screws
or lashings of the shrouds, while if slackness in these be permitted when the vessel
is rolling, considerable risk may be run from the funnel swaying and breaking its
connections.
This invention consists in substituting for the usual tightening screw or lashing
an automatically acting compensator constructed and arranged as we will now
proceed to explain by aid of the accompanying drawings, wherein,
Fig. 1 and 2 are elevations at right angles to each other showing one arrange-
ment of compensator according to this invention.
This arrangement, which is adapted to be connected to the lower end of the
shroud 1, comprises a grooved sheave or pulley 2 carrying below it a pin 3 for the
attachment of one end of a flexible wire rope 4. The sheave 2 is mounted in a
block or frame consisting of two side plates 2" connected together by three pins of
which the middle one 5 serves as the axle of the pulley and the upper and
lower ones, 3 and 3, as the means of attachment to the shroud 1 and wire rope 4
respectively. 6 is a base plate adapted to be secured by bolts or otherwise to
the deck of a ship, and to which is jointed a pulley block or frame 6* carrying a
sheave 7 and above this a smaller guide sheave 8, the upper end of the block or
frame being formed as an eye 9 for attachment to the lower end of a coiled
spring 10 which is used in tension. The flexible wire rope 4 is attached at one
end to the pin 3 below the pulley 2, is then passed between the guiding sheave 8
and the lower sheave 7, then round this latter sheave and up over the sheave 2,
and its other end is finally made fast to the upper end of the spiral spring as
shewn.
The lengths of the combined shroud and compensator are so adjusted that the
initial tension on the compensator spring 10, when the funnel, with which the shroud
and compensator are used, is cold, will be sufficient to prevent swaying, should the
ship be lying at anchor with fires down and exposed to a swell which causes
rolling. The said spring is so proportioned that the maximum expansion of
the funnel, due to forcing the fires, will not put an undue load or extension
upon it.
By the use of sheaves as described a certain amount of friction is obtained which
retards sudden stretching of the spring and thus acts to prevent swaying of the
funnel, whilst allowing the compensator to increase in length under the steady
strain due to the expansion of the funnel.
As will be obvious compensators comprising a spring, flexible wire or connection,
and sheaves acting in the manner described, can be combined and arranged in
various ways.
Figs. 3 to 7 inclusive are diagrammatic views illustrating several modified
arrangements of compensators according to this invention.
Fig. 3 shews an arrangement which is similar to that shown in Figs. 1 and 2,
but turned upside down, so that the block or frame 6 carrying the sheaves 7 & 8
is attached to the lower end of the shroud 1, and the frame 2 carrying the
sheave 2 and pin 3 is jointed to the base piece 6 secured to the ship's deck.
Fig. 4 shows an arrangement in which the sheaves 2, 7 & 8 are arranged
similarly to those shewn in Fig. 3, but the wire rope 4 is led around them as
shown so that both its ends are attached to the respective ends of the spring 10.
Fig. 5 shows au arrangement somewhat similar to that shown in Figs. 1 & 2
but in which the guide sheave 8 is dispensed with and the lower end of the
spring 10 is attached to a fixed pin 6° carried by an upward extension of the
base piece 6.
•
Fig. 6 shows an arrangement in which the wire rope 4 is simply passed over and
under the sheaves 2 and 7, attached respectively to the shroud 1 and deck
piece 6, and its ends are directly connected to the two ends of the spring 10.

page_text: Fig. 7 shows an arrangement somewhat similar to that shown in Fig. 6 but in
which the upper sheave 2 of the latter arrangement is replaced by a tee-shaped
piece 2 to which one end of the wire rope 4 and one end of the spring 10 is attached
as shown.
Fig. 8 shows an arrangement similar to the last but reversed in position the
sheave being attached to the shroud, and the one end of the rope and the one end
of the spring being attached to the base piece 6.
To increase the friction of compensators such as described the sheaves in the
arrangements shown in Figs. 1 to 6 inclusive may be each replaced by two or
more sheaves, or by a sheave having two or more rope grooves, and the rope
be passed several times around the sheaves in a manner that will be readily
understood, guide pulleys being provided when necessary to guide the rope clear
of the spring 10.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is :-
1. A compensator for a shroud of a steamship funnel comprising a spring, a
rope connected thereto, and one or more sheaves or pulleys around which the said
rope is passed, the said compensator being adapted to be connected to a shroud,
and to the deck of a ship, and the arrangement being such as to retard, when in
use, sudden stretching of the spring and consequent swaying of the funnel, whilst
providing for an increase in the length of the shroud under a steady strain due to
the expansion of the funnel, substantially as described.
2. Compensators for the shrouds of steam-ship funnels, constructed arranged
and operating substantially as hereinbefore described and shown in the drawings
annexed.
nexed
Dated this 28th day of September 1894.
For the Applicants,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent. ·