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Патент USA US3052908

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Sept. 11, 1962
6 Sheets-Sheet 1
,Filed April 22, 1959
Sept. 11, 1962
Filed April 22, 1959
6 Sheets-Sheet 2
Sept. 11, 1962
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Filed April 22, 1959
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Filed April 22, 1959
6 Sheets—Sheet 6
ilnlted States Patent
Patented Sept. 11, 1962
Marin-Marie Dnrand-Couppel de Saint Front, dit:
Marin-Marie, 33 Rue Boileau, l’aris, France
Filed Apr. 22, 1959, Ser. No. 808,190
Claims priority, application France Apr. 24, 1958
4 Claims. (Cl. 9-41)
‘her-tired wheels, at the base of said structure to permit
‘movement thereof transverse to said boat, and a launching
ramp on the ship extending athwartships and including
an inboard upper ramp portion sloping downward in an
outboard direction and an outboard ramp portion drop
ping sheer over the side of the ship, releasable means
being provided for normally retaining said carrier struc
ture with a boat thereon on shipboard with said fender
This invention relates to a boat launching apparatus
means resting on said inboard portion of the ramp, and
cable means for easing said structure and boat bodily
whereby lifeboats, quarter-boats and other small craft of
conventional construction may be quickly and safely
of said retaining means, with said fender means riding
lowered from shipboard and launched even from the
down the side of the ship.
down the ramp and over the side of the boat on release
higher side of a heavily listing ship.
The ramp is preferably provided in the form of a
In merchant and passenger steamers and other types of 15 ‘pair of U-sh-aped frames or girders or channels spaced
vessels, davits are generally used for launching life
fore-aft of the ship and each adapted to receive one pair
boats in case of emergency. In what is probably the most
of said fenders therein.
e?icient conventional boat-launching system currently in
The fenders mentioned above are preferably in the
use, the ‘boat is suspended from davits provided at the
form of wheels having resilient n'ms or solid or in?ated
ends of a carrier mounted through rollers on a ramp
tires. It will be understood however that other shock
sloping outboard, so that when the carrier is allowed to
absorbing means, not necessarily rotatable, might in some
move under its own weight along the ramp the boat will
cases be used as fenders instead of wheels.
describe an are adapted to bring it to a position clear
The carrier structure may comprise a pair of end
of the gunwale of the ship, whence it can then be lowered
frames each supported on a pair of wheels and longi
by easing the suspending cable as by releasing a brake
tudinal girders interconnecting the end frames at a
while further downward movement of the carrier is ar
relative spacing to accommodate the boat between them,
rested by striking an abutment surface at the base of
and the boat suspending means on each frame being so
the ramp. The truck can then be hoisted back to its
positioned with respect to the points at which the wheels
position on the ramp by a winch. Both operations can be
are journalled, that with said wheels riding the generally
performed without exertion of substantial muscular effort 30 vertical surface of the ship’s side the gun-Wale of the
by a single crew-hand and in fact a single operator can
boat will be held clear of said surface and spaced there
actually manage the launching of two boats almost simul
from by a prescribed amount.
‘The boat suspending means may comprise a pair of
V-shaped stirrup members ?rmly engaging the sides of
However, even with the highly elaborate lifeboat oper
ating systems just described, it has been observed in recent 35 the boat at each end and adapted to rest upon pivots
disasters involving modern vessels equipped with these
projecting from the end frames and releasably latched
systems that the lifeboats positioned on the higher side
on said pivots by suitable latching means operable from
of the heavily listing ship‘ could not be safely lowered
within the boat to release the boat from the carrier struc
all the way down and cast a?oat. In view of the list the
ture. The arrangement is such that the boat is able
boats on that side were not able to clear the projections 0n 40 to swing freely about said pivots. The carrier structure
the steel hull and/ or promenade deck and either foun
is suspended through cables operated by means of a
‘ered or were badly damaged. Thus only about half the
ship’s complement of lifeboats, i.e. that on the lower
In a modi?ed embodiment of the suspending means
or listing side, were available for performing their life
each end frame of the carrier structure is provided with a
saving function.
davit, the boat is suspended from both davits of the
The situation just described is common to all types of
carrier, and the carrier with the boat thereon is suspended
conventional boat-launching systems using davits and,
through cables that are selectively operable to lower the
although attempts have been made to overcome this
truck with the boat bodily or to lower the boat alone
difficulty by the use of in?atable rafts or boats of vari
in which case the truck is only allowed to move down a
limited amount to a point at which its davits project
ous types as rescue craft, in my opinion they do not bring
outboard to clear completely the side of the ship.
any satisfactory solution to the problem consisting of
lowering safely and quickly boatloads of passengers while
The above and further features of the invention and
avoiding their climbing down the side of the hull or
the advantages thereof will appear as the description
jumping into the water.
proceeds with reference to the accompanying drawings,
which are exemplary rather than restrictive:
It is therefore an object of this invention to improve
the rescue equipment on board ships while retaining the
‘FIGURE 1 is an elevational side View of a ship’s boat
standard construction of lifeboats substantially unaltered,
and for this purpose to provide a new and improved
secured on a carrier structure according to the invention;
FIGURE 2 is a corresponding view in plan;
boat launching system usable with generally standard 60 FIGURE 3 is an end view corresponding to FIGURE 2;
‘FIGURE 4 is a detail view showing the means for
structure of both the carrier ship and the carried boat,
latching an end frame on its launching ramp or U-shaped
whereby to enable the boats with their lead of human
lives to be safely lowered and cast a?oat under all emer
gency conditions including a condition in which the side
ends of a boat therebetween, fender means, such as rub
listing of the ship towards the launching side;
FIGURE 5 is a detail view showing the boat in stowed
and latched condition;
of the ship on which the boat is positioned is tilted steeply
upwards due to a heavy list of the ship towards the other
FIGURE 6 is a detail exploded View of the means for
latching the boat on its carrier structure;
In one important aspect of the invention, there is
FIGURE 7 is a general showing of apparatus accord
provided ‘apparatus for launching a boat from shipboard,
ing to the invention in various stages of a boat launching
which comprises in combination a boat carrier structure
process in the absence of list;
including releasable means for swingingly supporting the 70 FIGURE 8 shows the launching process in case of a
is being launched;
FIGURE 10 is similar to FIGURE 7 but relatesv to a
modi?ed form of the invention;
in the channels of the U-shaped girders, so that due to
the slope of the girders the carrier structure and boat
are urged by gravity down the girders in the outboard
direction. As shown in FIGURES 4, 5 and 7, the car
rier-and-boat assembly is normally retained in the nor
mal or stowed position described by cables 18 having one
FIGURE 9 is similar to FIGURES 7 and 8 but shows
the ship listing away from the side from which the boat
FIGURE 11 is a detail view showing the means for
end attached fast to ‘a carrier end frame at a single point
19 or at more than one point if desired by a suitable
spider or the like, and the cable being wound about the
vFIGURES l2 and 13 illustrate the last mentioned
modi?cation during a boat launching process under the 10 sheave of an electrically operated winch 20 (see FIGURE
7) a brake 21 being provided for controlling the rate at
same conditions, as those'in FIGURES 8 and 9 respec
which the structure is lowered. Safety latch means are
tively; and
provided separately for the carrier and the boat. Suitable
FIGURE 14 is a detail perspective view of the means
suspending the boat from the carrier in the modi?cation
of FIGURE 10;
for latching the boat to the carrier in the last mentioned
latching means for latching the carrier is shown at 22, 23
15 and 24 in FIGURE 4, and suitable means for ‘latching the
Referring ?rst to the embodiment illustrated in FIG
URES l to 9, apparatus according to the invention com
prises a boat carrying structure 1 which, in the normal
condition is positioned on and latched to :a stationary
boat are shown at 25 in FIGURE 5.
‘launching ramp (see FIGURE 7) comprising a pair of
supports 2 spaced fore-aft and positioned generally on a
levers 22a, 24a, 25a.
should be readily and quickly releasable by hand, as with
In FIG. 7, it will be particularly noted that point 19 is
located between pivot 9 and inboard roller 8b. The im
portance of this becomes apparent in position II where it
level with the upper deck of the ship, each support hav
ing a channel or U-shaped girder 3, 3a secured thereon,
at a slope of about 30% to the horizontal plane, and slop
ing downwardly in an outboard direction.
can be seen that the Weight of the boat concentrated at
pivot 9 tends to pivot carrier 1 counter-clockwise around
point 19 which is e?ectively a pivot. This urges each
wheel 8a against wall B to minimize bumping and so
A boat launching operation will now be described with
The boat carrier structure 1 comprises a pair of verti
cal end frames 6 and 6a interconnected by spaced longi
tudinal girders 5. Instead of a complete ‘four-sided frame
with two side members such as 5, the carrier may if de
sired include only a single centrally disposed longitudinal
The detailed con
struction of these latching devices need not be described
since various appropriate types are known, but they
30 reference to FIGURE 7 wherein it can be seen that rollers
Ba and 8b de?ne with the associated pivot 9 an angle B
which totals with angle A, between the ramp and the hori
zontal deck, an angle of less than 90'’. This produces a
member such as 5 with the two end frames 6, 6a con
nected across its opposite ends so as to provide a dou
‘ble-T structure.
Each end frame 6, may desirably comprise, as shown
greater stability by locating the pivots 9 inboard of the
especially in FIGURE 3, two projecting legs 7a, 7b and
a head 70, with the legs 7a, 719 having wheels 8a, 8b
outboard rollers 8a.
The latches 22 to 25 are ?rstreleased. The carrier
1 is now retained only by the cables 18 fast at 19 to the
'journalled on them so that both pairs of wheels provide
'a rectangular support for the boat carrier. The wheels
end frames and reaved about guide pulleys 26. The
crewman then releases the brake gradually to ease the
and are ?tted with yielding tires, which may be solid 40 structure at a controlled rate, ‘with the wheels supporting '
the end frames travelling down the girders 3, 3a. As
rubber or in?atable. If desired, each leg 7a, 7b may
will be clear from FIGURE 7 the downward sloping upper
carry a pair of twin wheels rather than a single one. De
sections of each girder are followed by an arcuate section
sirably low-pressure, large-section in?atable tires are used.
merging into a vertical lower end section, and in order to
The upwardly projecting head 70 of each end frame
carries a strong pivot or spindle 9 projecting from its 45 enable the end frames of the carrier 1 readily to clear this
arcuate section as well as other projections on the side of
end. The pivots relating to both end frames of each
‘the ships the end frames are formed, as shown, with a
truck serve to support the stem and stern of a boat be
tween them, by way of inverted V-shaped stirrups 10, .. corresponding arcuate concavity 6a between the two
wheel-supporting legs 7a and 7b. On reaching the end
the construction of which is well apparent from the ex
ploded view of FIGURE 6. Each stirrup has a pair of 50 of the ramp tracks 3, 3a, the end frames and the entire
carrier 1 are bodily rotated to the positions shown in chain
sweptback arms adapted ?rmly to engage the sides of
lines at ‘11 in FIGURE 7, while the boat continues to re
the stern and stem of the boat, respectively preferably
tain its- horizontal condition due to the relative pivoting
by way of suitable reinforcing means. If desired the arms
of the stirrups about the pivots or spindles 9. The car
of each stirrup may engage the sides of a launching cradle
such as 11 in FIGURE 3. The top of each stirrup 10 55 rier 1 is at this time taking support against the vertical
side B of the ship’s hull by way of its wheels.
at the junction of its ‘branches is adapted to seat upon
On the boat’s having been lowered down to a point
the related pivot 9, so asto accommodate swinging of
the boat with rolling of the ship while affording a ?rm
level with the deck P at which the passengers are to be
taken aboard, the brakes are reapplied so that the boat
support for it.
is held at this position. At this point it will be observed
_- Releasable latching means 12 (see FIGURE 6) are
as shown are directed to ride transversely of the boat
provided ‘for preventing separation between the stirrups
and their pivots or spindles 9 as under strong jolts. The
latching means as shown comprise a rod 13 slidable
through a boss 14 in the stem or stem of the boat and
projecting from the boat into engagement with the cor
responding pivot or spindle 9, and a suitable linkage
that the carrier is ?rmly supported against the side B of
the ship by way of its four wheels, so that the boat is
held at a small but de?nite spacing .clear of the ship
averting damage to the boat.
When the boat has received its full complement of pas
sengers in the usual manner the brakes are again released
such as a lever 15 is'provided for shifting the latch rod
and the entire assembly including the carrier structure
13 between its projected and retracted positions. Longi
tudinal shifting motions of the boat are prevented by the
and boatload of people resumes its downward progress,
with the resilient tires of the carrier wheels engaging the
provision of a ?ange 17 on each pivot or spindle 9 co
operating with a transverse slot 16 formed across the
side of the ‘hull and preventing and/ or damping any
dangerous swinging of the boat and impacts of it against
the side of the ship. As the boat is brought down to the
top of the stinup.
The boat carrier 1 with the boat C supported thereon
surface of the sea M (as at positon III, FIGURE 7) the
isjrsupported upon the U-shaped girders 3, 3a of the
carrier truck continues to sink beneath the buoyant boat.
ramp, with the wheels of the end frames freely received 75 Thus the boat is released of its own accord from its sus
pension on its longitudinal cradle where this is provided,
end frames 2 of the boat carrier structure are in effect
formed as davits. As will appear from FIGURES 10
or directly from the pivots 9 of the carrier end frames.
It will be understood that the latch 13 was released at an
and 11, the upstanding leg of each end frame instead of
being ?tted with an inwardly projecting pivot or spindle
for swingingly supporting, through a stirrup as above
appropriate time e.g. during the lowering process by the
boat’s skipper. The boat is then headed away from the
sinking vessel in the usual way.
In the above description it was assumed that the side
of the carrier ship was substantially vertical during the
boat launching operations, and I shall now consider in
greater detail how these operations are affected by a heavy 10
list of the ship to one or the other side.
illustrates the case where the ship is listing towards the
side from which the boat is being lowered. The condi
tions are then broadly similar to what occurs with con
ventional boat launching equipment using davits. While
the descent of the boat is unimpeded by the ship’s hull,
the danger in these circumstances is that with heavy roll
ing of the ship, a high wind, and/ or uncontrolled move
ment of the passengers in the rescue boat, the latter was
heretofore liable to strike the ship with damaging force.
This hazard is greatly alleviated with the apparatus of
the invention owing to the shock-absorbing action of the
preferably rubber-tired wheels 8a, 8b of the carrier end
frames which effectively take up such impacts against the
ship’s hull and serve as fenders. Further, rocking of
the boat carrier structure may be minimized by the pro
vision of one or more chains such as 27 (FIG. 7) having
ends attached to one leg of an end frame and to a sup
porting cable so as to limit the amplitude of such swing
ing. Alternatively a similar effect is obtained with the
use, as previously mentioned, of spider means for attach
ing the cable ends to the end frames at one or more spaced
points; or both the limiting chain and the spaced-point
spider attachment may be used simultaneously.
FIGURE 9 illustrates the condition where the ship is
listing away from the boat being launched. As already
described, the adjacent stem or stern end of the boat, is
formed as a short davit jib 31 with an attached suspend
ing pulley.
The thus modi?ed apparatus may be operated in either
of two principal ways. If the ship is not listing away from
the launching side, the carrier structure 1 may ?rst be
eased from the normal position I (FIGURE 10) to the
position II wherein the end frames are substantially over—
lying the arcuate portions of the guide girders. Means
15 are provided for automatically retaining the structure at
that level from a retainer cable 33 having one end fas—
tened to a small truck 34 or trolley 34 riding along the
under surfaces of the girders, which trolley is adapted to
come up against a stop at the position 3411, whereupon
the boat suspended from its cable 32 as in conventional
davits, will then continue to move down to its a?oat posi
tion III.
Or alternatively, the carrier structure ‘and boat may be
bodily lowered as in the ?rst described embodiment of
the system. This latter procedure is illustrated in FIG
URES 12 and 13 which respectively depict the instances
where the ship is listing away from and towards the
launching side.
As already mentioned, in the embodiment now being
described the carrier frame is normally freely suspended
at the end of its retainer cable 33 in the position 35 (FIG
URE 10). In lowering the carrier to its intermediate
position II, the downward movement of the carrier is ar
rested by abutment against the stop 34a. This abut
noted this condition was heretofore regarded as especially
ment may be disabled (or shifted) by means of a releas
able hook 36 and the cables of the carrier structure and
boat are so combined that they will allow the boat to
formidable in conventional rescue operations to such an
extent that frequently none of the lifeboats on the listing
side could be used, sometimes with serious consequences.
be lowered alone when the trolley 34 abuts against the
stop 34a, or will allow both the boat and its carrier struc
ture to proceed downwardly together as explained above.
It is under these circumstances, then, that the present in
vention is of especial value. All four supporting Wheels
The downward rate of motion would of course be con
of the carrier structure are able to ride continuously down
the side of the slanting hull B, as clearly seen from FIG
URE 9, while constantly holding the boat C at a de?nite
distance from the hull clear from any projections thereon
such as side-lights, open gates and the like, owing to the
high rigidity of the carrier frames relatively to the wheel
axles and to the moderate pressure of the wheel rims
against the hull, which is only a fraction of the pressure
that would be sustained against a horizontal runway.
While the apparatus of the invention thus makes it
possible to eliminate completely the serious di?iculties
encountered with conventional launching equipment, this
trolled by conventional braking means.
FIGURE 14 illustrates one construction of the means
for suspending each end of the boat from the related davit
arm 31 of the adjacent carrier end frame. As shown the
suspension means comprise a pair of arcuate arms 37
having a similar function to the stirrup 1!} previously
described and interconnected by a crosspin 38 on which
a grooved block 39 is positioned between the arms 37,
the block cooperating with a T-shaped hoist hook 40
pivoted at 41 on the davit pulley-block 42. A latch 43
cooperates with the T-hook 40 to block it Within the
grooved block 39, the latch being operable by Way of
a pullrod 44 from within the boat to release the boat
result is achieved at the cost of only a very small increase 55 from the suspension means as she is nearing the surface
(if any) in the weight of suspended structure. While
the suspended weight is obviously somewhat greater than
that of the lifeboat alone, this is partly offset by the fact
of the sea.
It will be understood that the boat launching system of
my invention is applicable to all manner of rescue boats,
that the over-all weight of the deck superstructure is sub
stantially lessened due to the absence of conventional 60 lifeboats, quarter boats and other small craft, including
non-rigid in?atable boats and rafts, in which case each
davits with their heavy jibs. Further, due to the reduc
structure may carry a plurality, say ten, de?ated
tion in impacts sustained by the boat during launching as
boats on a common cradle.
described above, the lifeboat itself may in some cases
It will also be appreciated that the launching apparatus
be made more lightweight than it was heretofore found
65 of the invention is equally operable to hoist on shipboard
Another important consideration is that it is frequently
found very expedient in the case of a heavily listing ship
a boat riding alongside the ship.
For this purpose the
boat may be steered so as to overlie a cradle lowered
to cast off as much Weight as possible from its upper
from the apparatus of the invention or to a position in
decks, so that the casting off of the end frames of the
boat structure 1 together with the lifeboats as described
which the stirrups 10 ‘can be engaged with the pivots 9
above is highly desirable.
ceeding that of the cradle.
In the embodiment of the invention so far described
or 37, provided the boat to rescue is not of a length ex
The carrier structure 1 in either form of embodiment
the boat launching apparatus may be regarded as lack
described may be conveniently unloaded without external
ing davits in the conventional sense of this term. In the
assistance together with its boat upon a wharf and there
modi?ed embodiment shown in FIGURES 10 to 14, the 75 used for conveying the boat from one point to another as
between different wharfs or to storage, and can be shipped
aboard again with great ease and expeditiousness.
What I'claim is:
1. Apparatus for launching a boat having a stem and a
stern from a ship including an upper deck and an outer
from and merging smoothly with the same, said inboard
section sloping downwardly at a determinable angle with
respect to the horizontal and outboard towards said out
board section .thereby. enablingsaid boat carrying struc
ture to move from said inboard section to the outboard
section under the in?uenceof gravity, said outboard sec:
section having‘ an outboard end connected with the outer
vertical wall of the ship, said girders supporting said boat
the. upper deck of the ship, and a boat carrying structure
carrying structure inboard of the ship and forming a roll
operatively associated therewith, each ramp comprising
a U-shaped girder, said girder including a rectilinearly 10 ing path directed outboard of the ship to the outer wall
thereof, said boat carrying structure comprising a frame
sloping inboard section and a curved outboard section de
including spaced end portions and a connecting member
pending downwardly therefrom and merging smoothly
vertical wall, comprising a pair of stationary laterally
spaced launching ramps adapted for being positioned on
with the same, said inboard section sloping downwardly
at a determinable angle with respect to the horizontal and
outboard towards said outboard section thereby enabling
rigidly connecting said end portions, a pair of opposed
pivots ?xed to said frame, coupling members ?xed out
board at the stem and stern of the boat and swingably
supported by said pivots, means on the boat operatively
associated with the pivots for locking and releasing the
same and enabling detachment of each coupling mem
gravity, said outboard'section having an outboard end
ber and the respective pivot, the end portions of said
connected with the outer vertical wall of the ship, said
girders supporting said boat carrying structure inboard 20 frame each including inboard and outboard supporting
legs associated with'one of said girders, resilient rolling
of the ship and forming a rolling path directed outboard
members coupled to said legs, one of said rolling mem
of the ship to the outer wall thereof, said boat carrying
bers being coupled to each of said supporting legs re
structure comprising a frame including‘spaced end por
spectively, said rolling members being constrained to ro
tions, and a connecting member rigidly connecting each
of said end portions, a pair of opposed pivots ?xed to said 25 tate within said U-shaped girders and being adapted to
roll directly on the outer wall of the ship, cables cou
frame, collars on said pivots, inverted V-shaped coupling
pled to said end portions between said pivots and the in
members ?xed outboard at the stem and stern ends of the
1board rollers, and means coupled to said cables for low.
boat and swingably supported by said pivots, said V
ering said boat carrying structure with the boat to the
shaped members’ being provided with slots to accom
modate said collars, means on the boat operatively as 30 water level, said pivots and rollers de?ning an angle, hav
ing the outboard rollers at the vertex thereof, which.
sociated with the pivots for releasing the same and en
latter angle with said determinable angle totals less than
abling detachment of each coupling member and the
ninety ‘degrees.
respective pivot, said means including a bolt slidable With
3. Apparatus as claimed in claim 2 wherein said r0ll~
in each of said inverted V-shaped members to lock the
pivots therein, each end portion of said frame including 35 ing members are in?atable tires.
4. Apparatus as claimed in claim ‘3 comprising lock~
inboard and outboard supporting legs associated with one
ing means for locking the vboat carrying structure in a
of said girders, resilient rolling members coupled to said
position of rest on said ramps.
legs, one of said rolling members being coupled to each
said boat carrying structure to move from said inboard
section to the outboard section under the in?uence of
of said supporting legs respectively, said rolling members
being constrained to rotate Within said U-shaped girders 40
References Cited in the ?le of this patent
and being adapted to roll directly on the outer wall of the
ship, cables coupled to said end portions between said
Smith _______________ __ Feb. 23, 1864
pivots and the inboard rollers, and means coupled to said
I 1,116,761
Thompson ___________ __ Nov. 10, 1914
cables for lowering said boat carrying structure with the
Groleau ____; ________ __ Aug. 20, 1918
boat to the water level, said pivots and rollers de?ning an 45 1,276,055
Elsen _______________ __ May 31, 1921
angle having the outboard rollers at the vertex thereof,
Ellison ______________ __ Nov. 27, 1923
which latter angle with said determinable angle totals
Vreugdenhil ___________ __ Ian. 4, 1927
less than ninety degrees.
2. Apparatus for launching a boat having a stem and
Lofstrand _____________ __ Oct. 7, 1930
Hunt _______________ __ Nov. ‘8, .1932
outer vertical wall, said apparatus comprising a pair of
Vreugdenhil __________ __ Mar. 13, 1951
Fawkes ______________ __ Sept. 27, 1955
Stearn _______________ __ Jam 2, 1959
Great Britain ________ ._._ May 12, 1930
Denmark ____-_ _______ __ Aug. 5, 1946
a stern from a. ship including an upward deck and an 50
stationary laterally spaced launching ramps adapted for
being positioned on the upper deck of the ship, and a
boat carrying structure operatively associated therewith;
each ram comprising a U-shaped girder, said‘ girder in 55
cluding a rectilinearly sloping inboard section and a
curved outboard section depending downwardly there
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