An Improved Derrick, chiefly for Use on Ships' Decks.
Year: 1896

page_text: Date of Application, 28th Jan., 1896
Complete Specification Left, 28th Nov., 1806-Accepted, 2nd Jan., 1897
An Improved Derrick, chiefly for Use on Ships' Decks.
I. THOMAS GREY BARRON, of Elwick Road, West Hartlepool, in the County
of Durham, Superintending Engineer, do hereby declare the nature of this inven-
tion to be as follows:-
This invention relates to the derricks of the kind in use on ships' decks but is
applicable to derricks generally the jibs of which are required to swing round to
the right or left, carrying the load with them.
As at present constructed the jib of a derrick on which the loal is hoisted is
pulled round by manual labour, as for instance when the load lifted out of a ship's
hold through the hatchway is drawn round to the ship's side, the jib of the derrick
being slung by one span or guy rope only from the ship's mast and therefore
without tendency to sideward movement in either direction inasmuch as that there
can be no change of elevation of the jib itself for gravity to act on.
The object of my invention is to provide means to impart a sideward tendency
to the jib of the derrick by the aid of gravity this sideward tendency being applied
and controlled at will by the means hereinafter described.
Although the improvements which constitute my invention are equally applicable
to derricks generally in which the jib is required to swing to the side of the place
from which the load is lifted, I will describe my invention as applied to a derrick
in use on a ship's deck.
The derrick is attached in the usual way to the lower part of the mast by a
gooseneck or pivot placed a few feet above the deck. The outer or free end of the
derrick is supported by two spans or guy ropes attached to it one of which is
secured to an eye bolt or other equivalent arrangement on the mast side at about
the same height as the jih end or is taken over a pulley on the mast side down to
some other point of connection at a lower level.
A second span or guy rope is also attached to the same part of the outer or free
end of the jib and is carried over a pulley on the opposite side of the mast down
to a lever which is pivotally attached to the mast near the ship's deck or to a block
and tackle or winch or other suitable appliance by which the span or guy rope can
be taken in or given out at will over the pulley above.
The two spans or guy ropes attached to the same point on the derrick and
extending across to two points at opposite sides of the mast present the appearance
of two sides of a triangle which take the place of the one span or guy rope hitherto
in use.
And it will be found in practice that with one span or guy rope secured to a fixed
point and the other arranged to be let out or taken in at will the jib of the derrick
can be made to remain stationary in one particular position selected as its hoisting
position by adjusting the spans or guy ropes to suit this position with a tendency to
swing to the side of the span or guy rope of constant length by the action of
gravity as the other span or guy rope is let out and the elevation of the jih
lowered. The jib can be brought back again to the hoisting position by taking in
the adjustable span to its original length and raising the elevation of the jib as
much as it was lowered before.

page_text: By alternating the arrangement the swing of the jib will of course be to the other
side, and there would be no difficulty in practice in connecting each span or guy
rope to a lever or other equivalent arrangement, so that either span could be used
as the span of constant length, and the other of variable length as circumstances
required.
Dated thie 27th don of Januar 1806
I, THOMAS GREY BARRON, of Elwick Road, West Hartlepool, in the County
of Durham, Superintending Engineer, do hereby declare 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 :-
This invention relates to the derricks of the kind in use on ships' decks, but is
applicable to derricks generally the jibs of which are required to swing round to
the right or left carrying the load with them.
As ordinarily constructed the jib of a derrick on which the load is hoisted is
pulled round by manual labour, as for instance when the load lifted out of a ships'
hold through the batchway is drawn round to the ships' side, the jib of the derrick
being slung by one span or guy rope only from the ships' mast and therefore
without tendency to sideward movement in either direction, inasmuch as, that
there can be no change of elevation of the jib itself for gravity to act on.
The object of my invention is to enable loaded derricks to be swung with the
minimum of labour and in the shortest desirable time by providing means to impart
a sideward tendency or movement to the jib of the derrick by the aid of gravity,
this sideward tendency being applied and controlled at will by the means
hereinafter described.
Following my researches since filing my Provisional Specification I have found
that means have been discovered for imparting a sideward tendency of this kind
to the jib of the derrick and my invention will therefore be found to consist in the
special construction or combination of parts employed for effecting this purpose
and by means of which the derrick is more easily manipulated and adapted to the
particular work in hand at the moment.
Although the improvements which constitute my invention are equally applicable
to derricks generally in which the jib is required to swing to the side of the place
from which the load is lifted, I will describe my invention as applied to a derrick
in use on a ship's deck.
And in order that my invention may be clearly understood and readily carried
into effect, I will now proceed to describe the same with reference to the accom-
panying drawings, in which
Fig. 1 illustrates in elevation a derrick adapted for loading and discharging
cargo on board ship and constructed in accordance with my invention. Fig. 2 is a
plan of same
Figs. 3 and 4 are enlarged detail views in elevation and plan respectively of
Figs. 1 and 2, shewing the span connected to a bell crank lever.
Fig. 5 is a similar view to Fig. 3 representing the span connected to a small
hand winch.

page_text: Fig. 6 represents the span connected to a pair of blocks, all of which arrange-
ments are substantially the equivalents of one another; and Fig. 7 represents in
plan a modification of my invention.
Referring to Figs. 1 to 4 of the drawings, the derrick a is attachel in the
usual way to the lower part of the mast b by a goseneck or pivot c place a few
feet above the deck. The outer or free end of the derrick is supported by two
spans or guy ropes de attached to it, one d of which is secured to an eye bolt for
other equivalent arrangement on the mast side at about the usual height as the
jib end, or is taken over a pulley on the mast side down to some other point of
connection at a lower level. A second span or guy rope e is also attached to the
same part of the outer or free end of the jib and is carried over a pulley g on the
opposite side of the mast down to a lever & which is pivotally attached to the mast
near the ship's deck by which the span or guy rope e can be taken in or given out
at will over the pulley above. In order to effect this the bell crank lever h is
arranged so as not to afford effective leverage to the sustaining tensile strain of
the span e, that is to say that the arm is brought into line with the rope e as.
shown more particularly in Fig. 3. The hoisting chain or wire rope is led through
blocks ij to a winch k or the like in the usual manner. The two spans de or guy
ropes attached to the same point on the derrick and extending across to two
points/g at opposite sides of the mast present the appearance of two sides of a
triangle as will be seen in Fig. 2, which takes the place of the one span or guy
rope hitherto in use. And it will be found in practice that with one span or guy
rope secured to a fixed point and the other arranged to be let out or taken in at
will the jib of the derrick can be made to remain stationary in one particular
position selected as its hoisting position by adjusting the spans or guy ropes to
suit this position, with a tendency to swing to the side of the span or guy rope of
constant length by the action of gravity as the other span or guy rope is let out
and the jib lowered. The jib is brought back again to the hoisting pc-ition by
taking in the adjustable span to its original length and raising the jib as much as
it was lowered before. By alternating the arrangement the swing of the jib will
of course be to the other side, and there would be no difficulty in practice in.
connecting either span or guy rope to the lever & or other equivalent arrangement
so that either span could be used as the span of constant length and the other of
variable length as circumstances required. As for example, when the span e is
slacked out the jib swings into the position indicated by dotted lines at z in Fig. 2,
until the span d'is in tension; and when the span d is slacked out the jib swings in
the opposite direction until the span e is in tension as indicated at æ¹.
In Fig. 5 a small hand wineb ! is shown for taking in or paying out the span e
as an alternative to the bell crank lever arrangement hereinbefore described; or
a pair of blocks m may be employed for the same purpose as shown in Fig. 6.
Fig. 7 illustrates a modification of my invention in which a single span e' is
connected to a bridle or two short spaus e2 e by a ring or hoop n in substitution
for two long spans as bereinbefore described.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is :-
1. In providing means for imparting a sideward movement to the jib of a
derrick crane by the aid of gravity, the use in combination with a guy rope or
span of constant length of a second guy rope or span of variable length, the two
ropes or spans being connected to the mast or centre post and converging to their
connection with the jib itself, or with a single guy rope extending to the jib as
shown in Fig. 7, in the form of two sides of a triangle, the adjustable span being
controlled and operated by a bell crank lever, winch, block and tackle arrangement
or the equivalents of these, substantially as and for the purpose as hereinbefore
described by the aid of the accompanying drawings.

page_text: 2. The arranging and combining of parts for facilitating the working of
derrick cranes, substantially as described with reference to the accompanying
drawings.
Dated this 27th day of November 1896.
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.