Improvements in Ships' Davits.
Year: 1898

page_text: Date of Application, 24th get,, 1898
Complete Specification Left. 24th Aug., 1899-Accepted. 7th Oct., 1899
Date of Application, 24th Qet,, 1898
Complete Specification Left. 24th Aug., 1899-Accepted, 7th Oct., 1899
ommunicated from abroad by Captain WILLIAM HENRY ROTHWELL, of The
British Indian Steam Navigation Company Limited, whose London registered
address is No. 9, Throgmorton Avenue, E.C., at present on the high seas.]
"
[Communicated from abroad by Captain WILLIAM HENRY ROTHWELL, of The
British Indian Steam Navigation Company Limited, whose London registered
address is No. 9, Throgmorton Avenue, E.C., at present on the high seas.
s.]
· Improvements in Ships' Davits.
I, HENRY HARINGTON LEIGH, Assoc.M.Inst.C.E., Fel.Ch.Inst.P.A., F.I.Inst.,
practising as Phillips and Leigh, of No. 22, Southampton Buildings, Chancery
Lane, in the Administrative County of London, Engineer and Patent Agent, do
hereby declare the nature of this invention to be as follows:
This invention relates to improvements in ships' davits.
The object of these improvements is to swing boats hanging by their tackles to
the davits and in their securing position inboard to a position outboard and
clear ready for lowering into the water with the minimum expenditure of time
and labour.
The davit is of the ordinary pattern and material, but fitted as follows, viz. :-
On it, in the required position is a shoulder all round except where a slotted key-
way is made. Fitted immediately under this shoulder is a movable roller bracket
band also with a key-way slotted in the inside of the band. The band itself is
fitted so as to move freely round the davit, or rather, fitted so that the davit will
turn freely within the band when the key is out of place, and the key-ways.
Key-way and key will be fitted so that the key being in place the bracket band
will be a fixture to the davit, moving together. If necessary another shoulder
(reverse) may be fitted on to the davit immediately underneath the bracket band
to support the said band.
Should the lower socket be required to be fitted with the gear as well as the
upper, the davit will be fitted with shoulders, bracket band, etc., similar to the
upper one, with the slight alterations which may be necessary due to the different
position.
The standard may be of the ordinary pattern in which case the top of it will be
fitted with the turning-gear only, the bottom socket fitting the davit neatly,
but allowing it to turn freely, or the standard may consist of a top and bottom
socket, the latter to be of sufficient depth to allow the davit to rise the required
height and yet leave sufficient socket to hold the davit securely. The two said
sockets will be connected to and supported by an inside and out-
side upright piece, the inside piece being supported by a bracket
piece reaching from near the top to the bottom, the whole connected to
and resting on a bed piece. On the top socket is a semi-circular inclined way,
grooved or otherwise shaped in a suitable manner to allow the roller to run on it
freely without slipping off and also to take the strain and friction properly. The
highest part of the inclined way will be inside, and the lowest outside, immediately
opposite or otherwise as required. The remaining portion of the circle will be
level or otherwise as may be determined upon or required; there will also be stops
fitted to prevent the davit from turning too far inwards or outwards.

page_text: The semi-circular inclined way on each davit will be on the side nearest each
other, and both davits will be fitted in a similar manner one to the other.
The inclination of the inclined way will be as much as may be required for
efficiency. The lower socket may be fitted in a similar manner to the upper if
required. The lower socket may also be fitted to act as an oil buffer as well, or
any other contrivance may be used to stop the davit from sinking and turning too
rapidly should the vessel be rolling heavily, or for other reasons it be found
necessary to employ such means. No standard may be used, but the top and
bottom (upper and lower) sockets may be secured and supported by other suitable
means, for example the upper socket may be secured to and supported by the
ship's side rail or the boat's skids, and the lower socket secured to the ship's
covering board or side.
The roller bracket band is made to fit round the davit closely yet so as to allow
the band to move freely round the davit. On the said band is a lug or bracket,
in which the roller will be pinned, the pin of the roller to pass through the outside
portion of the said lug or bracket, then through the roller-hub through the
inner portion of the bracket and into the band; the whole being made and fitted
so as to give the greatest freedom to the roller and the greatest strength generally.
The shoulder on the davit, the bracket hand bracket and roller will be in such posi-
tions that by turning the davit inboard, the roller will take on to and move up the
inclined way carrying the davit with it until when the davit is in its proper
position inboard the roller will be on its highest position; they will also be fitted
so that when the davit is turned outboard and in position to lower away the boat,
the heel of the davit will be resting on the bed piece or socket bottom and the
roller free and slightly above the way in such a manner that the jarring of
lowering the boat will not hurt or put any strain on either the roller bracket,
band, or inclined way, the socket below the way taking the whole of the strain
and jarring.
The roller has its outer rim shaped to fit the inclined way. The whole is
fitted so that when the davit is at its highest position it will be sufficient inboard
to allow the boat to be placed on to its chocks and when at its lowest position and
resting on the bed piece or lower socket bottom it will be sufficiently outboard or
in a position to allow the boat to be lowered freely into the water.
The davit is fitted in the ordinary manner with guys and spans, the latter
being fitted on the top of the davit head in a suitable manner to permit the
davit to turn freely under them without interfering with their action. The guy
is preferably a pendant and whip.
The operation of the invention is as follows:-
Assuming it is required to turn the davits inboard with the boat hanging by its
tackles to them: Take out or unship the key which keys the roller bracket band
to the davit and the davit will be free of the automatic gear and will act in the
ordinary manner simply turning on its heel.
After securing the boat inboard it is required to prepare the davits for turning
outboard automatically: Turn the davit outboard, place or ship the key which
secures the roller bracket band to the davit and then by turning the davit inboard
again, the roller will run up the inclined way until it reaches the highest position,
hook on the tackle to the boat and haul taut the guys and the davits will be ready
for action when required.
To turn the davits outboard with the boat hanging by its tackles to them and
supposing it is requisite that the forward end of the boat should go out first; then,
by letting go and overhauling the forward guy by taking a pull on the after guy
to assist, the roller will at once come on to the inclined way, and the weight of
the boat and davit sinking will carry the roller down the inclined way and so
turn boat and davit outboard when the forward davit has turned slightly
outside the fore and aft line (or line of the ship) let go and overhaul the after
guy and each will assist the other turning outboard; when in the required position
haul taut the guys and the boat is ready for lowering.

page_text: .
Should a vessel in which this gear is fitted be rolling heavily or have a heavy
list towards the side, the boat has to be swung outboard, on the oil in the lower
socket, or other contrivance will prevent the davit from sinking and turning too
rapidly and so avoid heavy jarring and damage.
Deted the 21th dov of October 1808
Improvements in Ships' Davits.
I, HENRY HARINGTON LEIGH, Assoc. M. Inst.C.E., Fel.Ch.Inst.P.A., F.I.Inst.,
practising as Phillips and Leigh, of No. 22, Southampton Buildings, Chancery
Lane, in the Administrative County of London, Engineer and Patent Agent, 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.
The object of these improvements is to swing boats, hanging by their tackles
to the davits and in their securing position inboard, to a position outboard and
clear ready for lowering into the water, with the minimumi expenditure of time
and labour.
I will now proceed to describe my invention in detail reference being had to
the accompanying drawings, in which:-
Figure 1 is a side elevation of one of the davits supported in a standard and
fitted with my improved turning gear.
Figure 2 is a plan of the supporting bracket, an inclined way or track thereon.
Figure 3 is a central vertical section through Figure 1.
Figure 4 is a plan of the fixed collar or shoulder b.
Figures 5 and 6 are the plan and front elevation respectively of the loose collar
or band carrying the roller.
Figure 7 shows in side elevation a davit erected in position as on a ship, the
adjacent parts of the ship being also shown and the davit being of the prolonged
type which reaches a lower deck and dispenses with a bracket for supporting the
two sockets.
Similar reference-letters indicate the same parts throughout.
The davit a is of the ordinary pattern and material but fitted with a turning
gear as follows, viz.:-On it, in the required position is fixed a shoulder b all
round except at where a slotted key-way c is made. Fitted immediately under
this shoulder is a movable collar or roller bracket band d also provided with a
key-way slotted in the inside of the band. The band itself is fitted so as to
move freely round the davit, or rather, fitted so that the davit will turn freely
within the band when the key el is out of place, and the key-ways, and key will
be fitted so that the key being in place the bracket band will be a fixture to
the davit, moving together. If necessary another shoulder (reverse) may be
fitted on to the davit immediately underneath the bracket band d to support the
said band.
Should the lower socket e¹ in the standard f be required to be fitted with the
turning gear as well as the upper one e, the davit will be fitted with a shoulder
or shoulders, bracket band, etc., similar to the upper one, with the slight alterations
which may be necessary due to the different position.
The standard may be of the ordinary pattern, and fitted with the turning-gear
at the top only; the bottom socket e fitting the davit neatly, but allowing it to
turn freely, or the standard may consist of a top and bottom socket, the latter

page_text: to be of sufficient depth to allow the davit to rise the required height and yet
leave sufficient socket to hold the davit securely. The two said sockets are
connected to and supported one above the other by the standard f, the whole
connected to and resting on a bed piece f¹. On the top socket e is a semi-
circular or spiral inclined way or track g, grooved or otherwise shaped in a
suitable manner to allow a roller h mounted on an axle in the collar d to run on
it freely without slipping off and also to take the strain and friction properly.
The highest part of the inclined way g will be inside, that is towards inboard,
and the lowest outside or outboard, immediately opposite or otherwise as required.
The remaining portion g¹ of the track will be level or otherwise as may be
determined upon or required. There will also be stops i, fitted to prevent the
davit from turning too far inwards or outwards.
The semi-circular inclined way on each davit will be on
other, and both davits will be fitted in a similar manner.
the side nearest each
The inclination of the inclined way will be as much as may be required for
efficiency. The lower socket may be fitted in a similar manner to the upper if
required. The lower socket may also be fitted to act as an oil buffer or step
bearing as well, or any other contrivance may be used to stop the davit from
sinking and turning too rapidly should the vessel be rolling heavily, or for other
reasons it be found necessary to employ such means.
The standard f may be
dispensed with and the top and bottom (upper and lower) sockets may be
secured and supported by other suitable means, for example the upper socket may
be secured to and supported by a bracket secured to the ship's side rail j or the
boat's skids, and the lower socket secured to the ship's covering board or side k;
or the said sockets may be secured direct to the decks as shown in Figure 7.
The roller bracket band d is made to fit round the davit closely yet so as to
.allow the band to move freely round the davit and the davit in the band. On the
said band is a lug or projection in which the roller is pinned, the pin of the
roller passing through the outside portion of the said lug or bracket as shown,
then through the roller hub through the inner portion of the bracket and into
the band or collar d; the whole being made and fitted so as to give the greatest
freedom to the roller and the greatest strength generally. The shoulder bon
the davit a, the bracket band d, lug and roller will be in such positions that
by turning the davit inboard, the roller will take on to and move up the inclined
way or track 9 carrying the davit a with it until when the davit is in its proper
position inboard the roller will then be on the highest part of the track; they
will also be fitted so that when the davit is turned outboard and in position to
lower away the boat, the heel of the davit will be resting on the bed piece or socket
bottom e¹, and the roller h free and slightly above the track in such a manner that
the jarring of lowering the boat will not hurt or put any strain on either the roller
bracket, band, or inclined way, the socket el below the way taking the whole of the
strain and jarring.
The
The roller has its outer rim or periphery shaped to fit the inclined way.
whole is fitted so that when the davit is at its highest position it will be sufficiently
inboard to allow the boat to be placed on to its chocks and when at its lowest
position and resting on the bed piece or lower socket bottom ell, it will be sufficiently
outboard or in a position to allow the boat to be lowered freely into the water.
The davit a is fitted in the ordinary manner with guys and spans, (not shown
in the drawings) the latter being fitted on the top of the davit head in a suitable
manner to permit the davit to turn freely under them without interfering with
their action. The guy is preferably a pendant and whip.
The operation of the invention is as follows:-
Assuming it is required to turn the davits inboard with the boat hanging by
its tackles to them: Take out or unship the key which keys the roller
bracket band d to the davit a, and the latter will then be free of the automatic
gear and will act in the ordinary manner simply turning on its heel.
After securing the boat inboard it is required to prepare the davits for turning

page_text: outboard automatically: Turn the davit outboard, place or ship the key c¹ which
secures the roller bracket band to the davit and then by turning the davit inboard
again, the roller will run up the inclined way until it reaches the highest
position; hook on the tackle to the boat and haul taut the guys, and the davits
will be ready for action when required.
To turn the davits outboard with the boat hanging by its tackles to them and
supposing it is requisite that the forward end of the boat should go out first;
then, by letting go and overhauling the forward guy and by taking a pull on the
after guy to assist, the roller will at once come on to the inclined way, and the
weight of the boat and davit sinking will carry the roller down the inclined way
and so turn boat and davit outboard when the forward davit has turned slightly
outside the fore and aft line (or line of the ship) let go and overhaul the after
guy and each will assist the other turning outboard; when in the required position
haul taut the guys and the boat is ready for lowering.
Should a vessel in which this gear is fitted be rolling heavily or have a heavy
list towards the side, and the boat has to be swung outboard, the lower socket e¹
is filled with oil on which the heel of the davit rests, or any other other contrivance
may be used which will prevent the davit from sinking and turning too rapidly,
and so avoid heavy jarring and damage.
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 claim is
In ships' davits, the combination with the davit rod of a collar mounted loose
on thereon and having a keyway, a collar mounted fast on the davit rod and
having a keyway coinciding with the keyway in the loose collar, a key fitting said
keyways, a roller mounted in said collar, and an inclined spiral way or track
supported beneath said roller, substantially as described.
the sten day of August love.
HENRY H. LEIGH, C.P.A.,
No. 22, Southampton Buildings, Chancery Lane, London, W.C.