Improvements in or relating to Ships' Davits.
Year: 1893

page_text: Date of Application, fat Nov., 1893 .
Complete Specification Left. 1st Aug. 1894-Accepted, 1st Feb., 1895
PROVISIONAL SPECIFICATION.
Improvements in or relating to Ships' Davits.
I, CUTHBERT Gardner, of Roseberry House, Redcar, in the County of York,
Retired Innkeeper, do hereby declare the nature of this invention to be as
follows:-
My invention relates to ships' davits for lowering and lifting ships' boats at sea.
The object of my invention is to construct ships' davits so that when the boat is
loaded and the davits are released they run out by the action of gravity far enough
to suspend the boat over the open water to be lowered down at will by the
occupants of the boat with or without the assistance of those on deck, the lowering
tackle operating in such a manner that both ends of the boat reach the water at the
same time and the boat never loses its level position.
By using davits constructed according to my invention I dispense with the usual
space taken up by ships boats on deck, and with chocks so that the boat hangs
clear of the deck, or I occupy the usual space on deck by a second boat to be slung
from and raised or lowered by the same davits.
In carrying my invention into effect I erect columns fixed to the deck of the
ship of any height or distance apart, to suit the dimensions of the ships' boat.
Girders of H section are so fixed on the top of these columos that their grooves
are available for use as tracks along which the davits travel in and out in the
manner required. I construct these moveable davits in the form of triangular
frames with the inclined or hypotenuse side extending to a suitable height above
and beyond the frames to overhang the boat's centre, these davits are connected
together so as to form one structure with a platform between them the structure so
formed being suitably mounted on rollers to run in the grooves of the H girders,
which are inclined towards the ships side so that the davits and boat with its crew
run out when free by the action of gravity suitable provision being made to arrest
the outward movement at the proper moment.
The upper end of each davit is made open to house a pulley which is fixed to and
rotates with a spindle extending from the one davit to the other davit corresponding
to which another spindle extends between the davits at a lower position to which
rollers are fixed corresponding in position with the pulleys above so that a rope is
wound round each roller and carried over the corresponding pulley above to its
connection with a ring fixed in the boat by which arrangement both ends of the
boat are lowered or raised equally and simultaneously. The descent of the boat is
controlled by a baud brake fixed at some intermediate position on the roller spindle
to which is connected a rope which is carried over a roller on the spindle above to
be grasped and operated by a man in the boat. The same brake can likewise be
controlled from the travelling davits or ships deck. This lower spindle is furnished
at each end with.a handle or crank to be used in raising a boat from the sea to the
ship or if required to lower the boat into the sea. Provision is made for pulling
the davits back to the inward position, consisting of any suitable mechanical
arrangement for the purpose such as pullies and tackle or the like which can be
readily operated on deck and the boat is lashed to the davits in the ordinary way
for safety and security in all weathers. In order to prevent the davits running
back on a sudden lurch of the ship in a rough sea each davit is furnished towards the

page_text: back part with a paul which engages in a rack on the girders or such equivalent:
arrangement as will be effective to prevent damage being done.
Dated this 31st day of October 1893.
G. J. CLARKSON,
Chartered Patent Agent, Stockton-on-Tees,
Agent for the Applicant.
1, CUTHBERT GARDNER, of Roseberry House, Redcar, in the County of York,
Retired Innkeeper, 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 :-
My invention relates to ships' davits for lowering and lifting ships' boats at sea.
The object of my invention is to construct ships: davits so that when the boat is
required to be used the davits themselves can be made to travel by suitably geared
mechanism whether aided or not by the action of gravity near enough to the ships'
side to suspend the boat over the open water to be lowered down at will either by
the occupants of the boat or by persons on the ships' deck, the lowering gear
operating in such a manner that both ends of the bont reach the water at the same
time, the boat never losing the level position.
In order to clearly describe how my invention is carried into effect, I will now
refer to the accompanying drawings in which the same is illustrated complete in all
its parts with a boat slung therefrom.
Figure 1 is an end elevation of the apparatus bringing into view in two positions
one davit with its gear and boat slung therefrom, namely with the boat housed and
secured as when not in use as shown in full lines, and with the davit run out and
the boat lowered as shown in dotted lines, the boats beams or structural parts
which occupy the same fixed positions in either case being shown in full lines.
Figure 2 is a part sectional elevation giving an end or edgewise view of one
davit with suitable gearing mechanism attached thereto and is taken on line x x of
Figure 1, more especially to show the provision for mounting the davits on rollers
to run along the fixed beams in the manner required for the purposes of my
invention.
Figure 3 is a side elevation of the apparatus as a whole with a boat slung
therefrom in the hoisted or same position as shown endwise in Figure 1.
In carrying my invention into effect I erect or utilize columns or stanchions a,
fixed to the deck of the ship of any heiglit or distance apart to suit the dimensions
or requirements of the ships' boat. Girders or boat beams 6 of H or channel
section or of the usual top and bottom flange arrangement with intermediate web
construction are so secured to the top of the fixed columns or stanchions a that
they are available for use as tracks along which the davits travel in and out in the
manner required. What may be taken as a convenient form of girder is illustrated
more especially, in Figures 1 and 2. In this construction the top and bottom
booms of channel iron are secured together by the webs or bracket plates
which are cut short and so leave an open space between the booms through
which the shaft of the friction or coil roller Cextends into the lower limbs d d
of each davit which lower limbs are set apart to enable them to move along
the sides of the girder without undue sideward movenient and to come Bush
with the bracket or web plates 6 edgewise, by which the travel of the davits
in either direction is brought to a standstill at the proper time. These limbs d d
are mounted by suitable bearings on the upper and under rollers, cl, c³, c, c,
which are suitably provided to take up all Lilting, rocking or frictional strains

page_text: of the davits upon the boat. beams, and so to keep the davits in their proper
or erect position relatively to the fixed frames or boat beams b. These moveable
davits are constructed in any suitable form such as the triangular converging
of the two upper members d' d terminating in the overhanging boom or jib d
These
extending above and beyond the frames to overhang the boats' centre.
davits are connected together as one structure with a platform or the like
between them, so that the structure so formed runs in and out along the girders >>
on, or by means of the rollers c², c³, c, and the boat beams bare set to a suitable
incline in the direction of the ships' side if it should be desirable to impart a.
tendency to the davits to run out when free by the action of gravity. But in
order to effectually control the in and out movement of the davits, I provide a
driving shaft e with chain wheel and pinion secured thereto; the said pinion
being geared at will or permanently geared to the spur wheel fs on the friction
or coil wheel shaft e, so that the chain-wheel can be used at any time to
operate the friction or coil wheel c in either direction and so bring about the
requisite movement of the davits for which purpose a rope is secured at both
ends as shown and coiled round the friction or coil wheel c with the requisite..
grip to prevent skidding.
:
The davits being run out to the position shown in dotted lines in Figure 1
the lowering gear is now brought into operation and consists of the usual pulley.
blocks and steel fall arrangement slung from the end of the jib ', but in order
to secure a simultaneous movement of the boat at both ends, by which the boat
retains at all times a level position, I provide between the davits a drum
shaft on which are mounted and secured thereto and preferably as near as
possible to the davits themselves the drums g from each of which the lowering
rope g is paid out. As these drums must share the movement of the same
shaft it is obvious that a proper adjustment and tension of the ropes g is all
that is required to ensure a uniform movement of the boat at both ends, and
that in fact no other movement is possible apart from accidents. The movement
of the drums g in paying out the lowering ropes g' is regulated by the occupants
of the boat by means of check ropes g* connected to the free end of the brake
straps h, which can be thus applied from the boat. But in addition to this
provision for regulating the descent of the boat into the water, I provide on
the drum shaft g the spur wheel into which I gear the pinion f' and so
control the drums g from the ships' deck, or if the pinion 71 is preferably
permanently geared to the spur wheel f of the friction or coil wheel shaft the
drum spur wheel f³ can be readily provided with its own controlling shaft,
pinion and hand or chain wheel. Where steam power is available the rope 91
can be led through leading blocks to say, the winch or capstan and the raising
or lowering of the boat be operated by steam.
The housing chocks j if required at all are slung from the davits frames by
means of a series of blocks hinged together in endwise contact so that they
are capable of exerting a thrust on the chocks j in the outward direction until
the said chocks fall over the boat beams down to the position shown in dotted
lines in Figure 1, from which they are again drawn up to the position shown
in full lines in Figure 1 on the return of the davits to the inward or housed
position.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
olaim is :-
Firstly. In ships davits the combination with fixed girders mounted on columns
or stanchions of moveable davits having carrier wheels and gearing mechanism for
operating them, the said davits being connected together as one structure and
furnished with raising and lowering gear, substantially as and for the purposes as
bereinbefore described with reference to the accompanying drawings.
Secondly. In ships' davits the combination with moveable davits connected

page_text: together as one structure and mounted upon girders and columns, of drums secured
to one drum shaft, the said drums being preferably set as near to each davit as
possible for paying out the lowering tackle to each end of the boat simultaneously,
substantially as hereinbefore described with reference to the accompanying
drawings.
Thirdly. In ships' davits the combination with moveable davits connected
together as one structure and mounted upon girders and columns, of drums secured
to one drum shaft and controlled by brakes for regulating the descent of the
boat into the water from the boat itself, with or without a controlling shaft geared
into the drum shaft and operated from the ship's deck, substantially as hereinbefore
described with reference to the accompanying drawings.
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.