Improvements in Ships' Davits.
Year: 1893

page_text: Date of Application, 28th Apr., 1893
Complete Specification Left, 28th Feb., 1894-Accepted, 28th Apr., 1894
PROVISIONAL SPECIFICATION.
Improvements in Ships' Davits.
I, RICHARD ROPER, of Palace Chambers, 9 Bridge Street, Westminster, in
the County of Middlesex, Marine Contractor and Engineer, do hereby declare the
nature of this invention to be as follows:-
This invention relates to Improvements in Ships' Davits.
A davit constructed according to this invention consists essentially of a suitable
bent bar pivoted to the side of the vessel so that it may be rocked from its
approximately vertical position to overhang the side of the vessel.
According to one method of carrying this invention into effect I pivot such
a bar at its lower end to the deck of the vessel close up against the side of the
deck house or other erection so that it shall occupy as little as possible of the
deck space.
At a point lying at or near the centre of the bar I form an
elongated cavity or slot to receive a nut. Within this nut lies a horizontal
screw spindle provided with suitable means of rotation so that it may be operated
to cause the said nut to travel in a horizontal direction. This movement will
of course be communicated to the bar constituting the davit which will move
upon its pivot so that its free end may be moved outwards to suspend the boat
over the water or inwards to bring the boat upon the deck as may be required. .
It will be understood that the screw spindles actuating each davit of a pair
are geared together so that both ends of the boat may be moved together.
According to a modified arrangement of this invention I pivot the lower end
of the davits to the rail of the vessel, or to the skid or other support, and curve
them inwards so as to suspend the boat within the line of the rail. Instead of
housing the nut upon the screw spindle within a cavity in the davit itself I
pivot to it one end of a link the other end of which is pivoted to the upper
part of the davit. It will be seen that the movement of the nut is communi-
cated to the davit through the agency of the said link. In this arrangement
the screw spindle may run along the side of or immediately below the skid or
other erection extending to the rail of the vessel and having a clear gangway
underneath.
According to a third modification I extend the davit beyond the point at
which it is pivoted and increase its width so as to form a sector or quadrant
upon the edge of which I form a number of teeth which gear with toothed
pinions or with a rotating worm or other suitable devices for moving the davit
upon its pivot.
Dated the 26th day of Anril 1803
CASTLE SMITH,
Invention" Office, 54, Fleet Street, London, E.C.,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Ships' Davits.
I, RICHARD ROPER, of Palace Chambers, 9 Bridge Street, Westminster, in
the County of Middlesex, Marine Contractor and 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:-
This invention relates to Improvements in Ships' Davits.

page_text: A davit constructed according to this invention. consists essentially of a suitable
bent bar pivoted to the side of the vessel so that it may be rocked from its
approximately vertical position to overhang the side of the vessel.
•
According to one method of carrying this invention into effect.1 pivot such
a bar at its lower end to the deck of the vessel close up against the side of the
deck-house or other erection, so that it shall occupy as little as possible of the
deck space.
At a point lying at or near the centre of the bar I form an
elongated cavity or slot to receive à nut. Within this nut lies a horizontal
screw spindle provided with suitable means of rotation so that it may be operated
to cause the said nut to travel in à horizontal direction. This movement will
of course be communicated to the bar constituting the davit which will move
upon its pivot so that its free end may be moved outwards to suspend the boat
over the water or inwards to bring the boat upon the deck as may be required.
It will be understood that the screw spindles actuating each davit of a pair
are geared together so that both ends of the boat may be moved together.
According to a modified arrangement of this invention I pivot the lower end
of the davits to the rail of the vessel or to the skid or other support, and curve
Instead of
them inwards so as to suspend the boat within the line of the rail.
housing the nut upon the screw spindle within a cavity in the davit itself, I pivot
to it one end of a link, the other end of which is pivoted to the upper part of
the davit. It will be seen that the movement of the nut is communicated to the
davit through the agency of the said link. In this arrangement the screw
spindle may run along the side of or immediately below the skid or other
erection extending to the rail of the vessel, and having a clear gangway
underneath.
"
According to a third modification, I extend the davit beyond the point at which
it is pivoted and increase its width so as to form a sector or quadrant upon the
edge of which I form a number of teeth which, gear, with, toothed pinions or
with a rotating worin or other suitable, devices for moving the davit upon its
pivot:
And in order that my invention may be more fully understood and carried
into practice I will now proceed to describe the same with reference to the
accompanying drawings, of which
.' 11
Fig. is a side elevation, and Fig. 2 a transverse section of a part of a ship
'provided with davits constructed and operated according to my invention;
Figs. 3, 4, 5, 6; 7; and 8 enlarged,details;
Fig. 9 transverse section of part of ship with a modified davit applied, and
Figs. 10 and 11 an elevation and, transverse section of a part of a ship illustrating
further modified davits.
1.
As shown in Figs. 1 to 8 the davits a, which are preferably hollow, and of square
section, are pivoted at their lower, ends to.the,deck of the vessel so, that, their lower
portion projects through the flying deck, normally rests against the side of the
deck-house or otherwise situated and shaped as to occupy as little deck space as
possible. At a point near the centre of these bars or davits a an enlarged cavity or
slot is formed in which slides a nut c. This nut has passing through it a screw-
threaded spindle a mounted to revolve in suitable bearings e attached to any
suitable part of the vessel so that by revolving said spindle in one direction the nut
and consequently the davit a will be caused to travel in one direction so that
upper end carrying the boat extend beyond the side of the vessel, whilst when
revolved in the opposite direction the davits will be again moved into their original
position.
its
.
The movements of each pair of the two spindles d and davits a I effect simul-
taneously, by gearing the ends thereof by bevel gearing e or the like to a shaft f
mounted in suitable bearing secured to the vessel at any suitable point and one end
of which gearing through bevel gears g to the lower end of a vertical shaft mounted
in bearings in a case or the like and geared at its upper end by bevel gears k to a
spindle mounted in bearings in the case and provided with handle m by means

page_text: l
of which it may be turned to cause the davits to be moved in the desired direction..
Said spindle may have mounted on it a ratchet wheel with which gears a pawl
pivoted to the case k whereby the movement of said spindle and consequently that
of the davits may be governed. The ropes and chains by which the boat is
suspended from the davits pass down the interior of said davits over suitable guide-
pulleys n and from thence are carried through suitable openings in the sides of said
davits round other guide pulleys to the drums of a suitable winch or windlass o
mounted on the ships flying deck or other suitable part.
It will thus be seen that not only can the davits be brought to extend over the
side of the vessel simultaneously but both ends of the boat may be lowered into the
water at the same time.
In the modified arrangement shown in Fig. 9 the davits are pivoted at their
lower ends to the rail, skid or other support of the vessel whilst the nuts on the
operating spindle d instead of being housed in slots in the davits are connected
thereto by a hinged connecting link p. In this arrangement the screw spindle d
may run along the side of or immediately below a skid or other erection extending to
the rail of the vessel, so leaving a clear gangway underneath.
In the further modification shown in Figs. 10 and 11, the davits extend beyond
the point at which they are pivoted and have formed or secured on their lower ends
a curved rack or sector q which gear directly by gear wheels on to the shaft f
operated as above described.
The upper ends of the davits may be turned inwards when desired as shown in
Figs. 10 and 11 so as to suspend the boat within line of the rail.
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) Davits hinged or pivoted at or near their lower end and operated directly or
indirectly by a screw-threaded. spindle acting through a nut capable of being
revolved simultaneously with a second similar spindle, substantially as and for the
purpose hereinbefore described and illustrated in the accompanying drawings.
(2) Davits hinged or pivoted at any suitable point and provided with a toothed
sector at or near their lower end gearing with suitable operating mechanism,
substantially as described and illustrated in the accompanying drawings.
(3) In connection with davits as above claimed, apparatus whereby both ends.
of a boat may be lowered or raised substantially as described and illustrated in the
accompanying drawings.
(4) Davits as above claimed having their upper ends turned inwards towards one
another, substantially as and for the purpose hereinbefore described and illustrated.
in the accompanying drawings.
(5) Davits constructed and operated substantially as described and illustrated in
the accompanying drawings.
LOJZ.
CASTLE SMITH,
"Invention " Office, 54, Fleet Street, London, E.C.,
Agent for the Applicant.