IMPROVEMENTS IN APPARATUS FOR DISENGAGING BOATS WHEN LOWERED FROM SHIPS' DAVITS, OR WHEN HOISTED 'OUT BY DERRICK OR STEAM CRANE
Year: 1882

page_text: LETTERS PATENT to The Honourable Francis George Crofton, Commander in
Her Majesty's Royal Navy Harbour Master of Kingstown in the County of
Dublin, Ireland for an invention of "IMPROVEMENTS IN APPARATUS FOR
DISENGAGING BOATS WHEN LOWERED FROM SHIPS' DAVITS, OR WHEN HOISTED
'OUT BY DERRICK OR STEAM CRANE."
"
PROVISIONAL SPECIFICATION left by the said Francis George Crofton at
the Office of the Commissioners of Patents on the 13th April 1882.
The Honourable FRANCIS GEORGE CROFTON, Commander in Her Majesty's
Royal Navy, Harbour Master of Kingstown, in the County of Dublin, Ireland,
"IMPROVEMENTS IN APPARATUS FOR DISENGAGING BOATS WHEN LOWERED FROM
SHIPS' DAVITS, OR WHEN HOISTED OUT BY DERRICK OR STEAM CRANE."
My Invention has reference to improvements in apparatus for disengaging boats
when being lowered over ships' sides in a simple and efficient manner, and is
designed to simplify such operations in the first instance when boats are lowered
by the ordinary davit arrangements as at present used, and in the second instance
when boats are hoisted out by the derrick or crane gear.
In carrying out the first part of my Invention I attach to the strops of the
lowering tackles eyes which enter suitable apertures formed in the thwarts and are
there hold by the short arm of a lever pivoted to the under surface of the thwarts.
The long arms of these levers stretch towards the side of the boat, and to their
free ends are attached pieces of wire rope whose free ends are carried up through
the thwarts and aft where they are secured to a slip. When these pieces of wire
are pulled taut the long arms of the levers are raised and the short arms caused to
enter the above described eyes and hold them fast, the weight of the boat being
now on these short arms. When in lowering the boat it is desired to disengage
her these pieces of wire are let go, the levers are released, their short arms
disengaging the block eyes and thereby setting the boat free of the tackles.
In hoisting out boats according to the second modification of my luvention

page_text: namely by derrick or crane gear I propose to fit or hook on the span to the boat in
the ordinary way, and in the centre of the span I arrange a ring to which is spliced
a short wire rope pennant thick at one end and tapering towards the other. This
pennant is passed over the hook of the lowering chain and carried down through
a hole in the centre thwart and over a suitably arranged pulley or roller fixed in
the bottom of the boat and the free end then belayed to a cleat attached to
the seat.
When it is desired to disengage the boat by this arrangement it is only necessary
to free the end of the wire rope from the cleat when the rope unwinds off the roller
or pulley and the boat is immediately free.
]

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Francis George Crofton in the Great Seal Patent Office on the
13th October 1882.
The Honorable FRANCIS GEORGE CROFTON, Commander in Her Majesty's
Royal Navy, Harbor Master of Kingstown, in the County of Dublin, Ireland,
IMPROVEMENTS IN APPARATUS FOR DISENGAGING BOATS WHEN LOWERED FROM
SHIPS' DAVITS, OR WHEN HOISTED OUT BY DERRICK OR STEAM CRANE"
My Invention has reference to improvements in apparatus for disengaging bonts
in a simple and efficient manner when being lowered over ships' sides; and is
designed to simplify such operations in the first instance when boats are lowored.
by the ordinary davit arrangement as at present used, and in the second place when
boats are hoisted out by derrick or crane gear.
In carrying out the first part of my Invention I attach to the strops of the
lower blocks of the lowering tackles eyes which enter suitable apertures formed in
the thwarts, and aro there held by the short arm of a lever pivotted to an iron
stanchion bolted to the keel and coming up under the thwarts. The long arms of
these levers stretch towards the side of the boat, and to their free ends are attached
pieces of wire rope which are carried up through the thwarts and aft where they.
are secured to a slip. When these pieces of wire are pulled taut the long arms of
the levers are in a horizontal position, and the short arins enter the eyes of the
lowering blocks above described and hold them fast, the weight of the boat being
now on these short arms.
When in lowering the boat it is desired to disengage her these pieces of wire
are freed from the slip and let go, the long arms of the levers are released, their
short arms disengaging the block eyes and thereby setting the boat free of the
tackles.
1
In hoisting out boats according to the second modification of my Invention,
namely, by derrick or crane gear, I propose to fit or hook on the span to the boat
in the ordinary way, and in the centre of the span I arrange a ring to which is
spliced a short wire rope pennant-thick at one end and tapering towards the other.
This pennant is passed over the hook of the lowering chain and carried down
through a hole in the centre thwart and over a suitably arranged pulley or roller
fixed in the bottom of the boat, and the free end then belayed to a cleat or slip
attached to the seat or thwart.
When it is desired to disengage the boat by this arrangement it is only necessary
to free the end of the wire rope from the cleat or slip when the rope unwinds off the
roller or pulley and the boat is immediately free.
In order that my said Invention may be more readily understood, I will describe
the accompanying drawings.
Fig. 1 is an elevation of a boat with the near side removed for the purpose of
showing the application of my invention.
Fig. 2 is a plan view.
Fig. 3 is part of a transverse section.
Figs. 4 and 5 are detail views, and
Fig. 6 is an elevation of a boat with near side removed illustrating a modification
of my Invention.
Similar letters indicate corresponding parts in all the views. A is the block of
the lowering tackle, in the strop of which an eye B is provided which enters an
aperture in the thwart, and is engaged by the lever c as shown in fig. 3. This lever
is pivotted on the iron stanchion d by means of the pipe e. thus constituting the
lever one of the first order,

page_text: The wire rope is attached to the free ends of these levers at f. and the ends of
these pieces of rope are carried aft and secured to the slip g. as shown in fig. 1. It
will be obvious that while these pieces of wire rope are pulled taut and the levers
maintained in a horizontal position the forked end of the levers will engage the
eyes of the lowering block, and immediately the wire rope is let go at the slip g.
the levers will assume the position indicated by the dotted lines (fig 3), thereby
disengaging the lowering block and setting the boat free. The wire ropes may thus
bo let go by one hand-by the officer or man in charge of the boat.
This arrangement may be worked automatically by shifting the pin or pivot of
the lever frome to e¹ when it becomes a lever of the second order, and directly the
boat becomes water-born the weight is taken off the forked ends of the levers and
their long ends fall setting the boat free. The levers being connected by a small
line the foremost one cannot fall before the after-they both work together.
In the modification of my Invention h. represents the ring to which is spliced the
short wire rope pennant which passes over the hook of the lowering chain and is
carried down through a hole in the centre thwart and over the pulley / fixed in
the bottoin of the boat. The free end is then belayed to the cleat or slip-l-attached-
to the seat.
Having thus described the nature of my said Invention and the manner of
applying the same in practice, I would have it understood that what I consider
new and useful, and therefore claim as the Invention to be secured to me by the
herein before in part recited Letters Patent is,
First. The use and application of the arrangement herein described for the
purpose of lowering ships boats, substantially in the manner specified and illustrated-
in reference to figs. 1 to 5. inclusive of accompanying drawings.
Second. The use and application of a wire rope pennant in connection-with-the-
lowering of ships' boats by ordinary crane gear in the manner substantially as
herein described and set forth in reference to fig. 6. of accompanying drawings.
In Witness whereof, I, the said Francis George Crofton, have hereunto set
my hand and Seal this Eleventh day of October, in the year of Our Lord,
One thousand eight hundred and eighty-two.
TRANCIS CEORGE CROFTON (r.<\