IMPROVEMENTS IN APPARATUS FOR ENGAGING, RAISING, RETAINING, LOWERING, AND DISENGAGING SHIPS' BOATS
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by William Barr and Robert Barr
at the Office of the Commissioners of Patents, with their Petition,
on the 18th June 1874.
We, WILLIAM BARR, Master Mariner, and ROBERT BARR, Engineer,
both of Glasgow, in the County of Lanark, North Britain, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN APPARATUS
FOR ENGAGING, RAISING, RETAINING, LOWERING, AND DISENGAGING SHIPS' BOATS,"
to be as follows, that is to say :-
This Invention has for its object the constructing and combining of
parts connected with ships' boats in an improved manner with a view
to such boats being more readily, safely, and efficaciously available than
heretofore on an emergency.
In carrying out the Invention the davits are fixed on a horizontal
shaft mounted in bearings fixed on the rail, bulwarks, or deck of the
ship. A worm toothed sector is fixed on a convenient part of the davit
shaft, and has in gear with it a worm on a shaft having a hand wheel
fast on it. The davits which are by preference curved have sheaves or
pullies at their extremities and also at other parts, and the ropes of

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chains by which the boat is suspended are passed over these sheaves or
pulleys, and have their inner ends made fast to rings or hooks fixed to
the rail, bulwarks, or deck at points which are at a certain distance
outwards from the position of the davit shaft. As the davits are turned
outwards by means of the worm shaft the ropes or chains pay out from
their ends in consequence of the distance between the fixed rings and
the first sheaves or pulleys being shortened by the turning over of the
davits, and the boat is lowered to a corresponding extent beyond the
movement directly due to the davits. Each rope or chain is connected
to the boat by what may be termed a blunt hook jointed to its bottom
end, this blunt hook being a metal tongue with a bevilled shoulder or
projection on one side near its point, and it cannot accidentally catch
on objects like a common hook. This blunt hook is thrust down into a
socket, and its lateral projection turns aside and gets under a blunt
holding latch pressed by a spring and centred, so that any strain on the
blunt hook causes it to be more firmly gripped. The holding latch is
made with a tongue by which it can be turned aside for releasing the
blunt hook when required; and in order to obtain the simultaneous
release of both ropes a rod or shaft is fitted longitudinally in the boat
and has wipers fixed on it in positions to act on the two holding latches,
whilst at any other part of it that is convenient a handle is fixed on it
to turn it by.
By another modification the blunt hooks are made with projections
on both sides, and are held by cup-like picces on the ends of the longi-
tudinal rod or shaft. The cups turn on fixed studs in which sockets arc
formed to receive the blunt hooks, and after the blunt hooks are entered
into the sockets through enlarged openings in the cups these cups are
turned round so as to cover and hold the lateral projections of the blunt
hooks.
For retaining the boat after it is raised levers are jointed to the davits,
and their outer ends are shaped to engage with the boat's keel, whilst
their inner ends are connected to fixed points in such a way that they
release the boat when the davits are turned outwards.