IMPROVEMENTS IN DETACHING APPARATUS FOR BOATS AND VESSELS
Year: 1885

page_text: I, JOHN DONALDSON, of Church Wharf, Chiswick, in the County of Middlesex
(a member of the firm of John I. Thornycroft and C) Steam Yacht and Launch
Builder do hereby declare the nature of said invention for "IMPROVEMENTS IN
DETACHING APPARATUS FOR BOATS AND VESSELS "to be as follows:-
My invention has for object to provide detaching apparatus of simple form
the use of which will enable boats or vessels of considerable weight such as torpedo
boats to be carried by and launched with safety from lowering tackle without
liability of one end of the boat or vessel, that may happen to be water-borne
becoming detached whilst the other end is not water-borne but is still suspended to
and held by the tackle. My apparatus is so arranged as hereinafter described that
when both ends of the boat or vessel are water-borne the lowering tackle will
become automatically detached from it.
To this end according to my invention the boat or vessel is suspended to links
attached to the lowering tackle by means of devices I will call bolts, each of which
in one arrangement is a curved bar forming one arm of a lever of the first order;
these levers are pivotted to frames or standards fixed in the boat or vessel to be
carried. Each bolt is or may be notched or recessed at its under surface and is so
shaped and arranged as to be capable of entering slots holes or openings formed in
the frame or standard to which it is pivotted and of moving out of the same, when
turned upon its fulcrum. Each lever is provided with a counterweight, or the
equivalent thereof, such as a spring, tending automatically to withdraw the bolt
from the slots or openings in its frame or standard.
The boat or vessel is suspended to links each of which engages with one of the
bolts above mentioned. The two levers with their bolts are connected in such a way
as to ensure their moving together, so as to prevent one of the bolts becoming
disengaged from the link that carries it unless the other bolt be at the same time
disengaged from its link.
A convenient arrangement of my apparatus as above set forth is as follows:--
Two levers with book-like arms are arranged one near each end of the boat and
are connected by one or more rods or rigid connections or by two or more flexible
connections such as chains. One end of each connection is secured to the notched
hook-like arm of one lever, whilst the other end of such connection is attached to
a reverse arm of the other lever in such manner that the notched hook-like arm of

page_text: one lever cannot leave a link with which it is engaged so as to detach its end of
the boat from the lowering tackle unless the other hook-like arm becomes in like
manner disengaged.
When the boat is water-borne at both ends the notched hook-like arms of both
levers are by simultaneous movement of the levers upon their fulcra consequent
upon the action of counterweights or other equivalent apparatus caused to become
automatically detached from the lowering tackle.
In lieu of rigid or flexible connections a fluid connection may be employed.
According to a modification the levers are arranged parallel with each other and
are rigidly connected by a rod or bar that acts by torsion to prevent one lever
moving without the other. A counterweight or counterweights or other equivalent
apparatus is or are employed as before to automatically detach the levers from the
lowering tackle.
Or the bolts instead of being in the form of pivotted hook-like arms may be
recessed bars able to slide within slots or holes in the frames or standards and
provided with springs or the equivalent thereof such as levers and counterweights
or levers and springs tending automatically to withdraw the bars from the
suspending links.

page_text: Improvements in Detaching Apparatus for Boats and Vessels.
I, JOHN DONALDSON, of Church Wharf, Chiswick, in the County of Middlesex
(a member of the firm of John I. Thornycroft & Co) Steam Yacht and Launch
Builder, do hereby declare the nature of my said 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 has for object to provide detaching apparatus of simple form, the
use of which will enable boats or vessels of considerable weight, such as torpedo
boats, to be carried by and launched with safety from lowering tackle without
liability of one end of the boat or vessel that may happen to be water-borne
becoming detached whilst the other end is not water-borne but is still suspended to
and held by the tackle.
My apparatus is so constructed with connected curved bolts and frames, standards
or brackets arranged as hereinafter described, that when both ends of the boat or
vessel are water-borne the lowering tackle will become automatically detached
from it.
Referring to the annexed sheet of illustrative drawings, Fig. 1 shows in side
elevation apparatus according to my invention, comprising two curved bolts, each
of which is a curved bar 1 forming part of one arm of a lever of the first order:
these levers are pivotted at 2 to frames or standards (or brackets may be used) 3
fixed in or on the boat or vessel to be carried as illustrated in Figure 7. Each bolt
is notched or recessed at its under surface 4 and is so shaped and arranged as to be
capable of entering slots, holes or openings formed in the frame or standard 3 to
which it is pivotted, and of moving out of the same when turned upon its fulcrum.
Either or each lever is provided with a counter-weight 5 or the equivalent thereof,
such as a spring tending automatically to withdraw the bolt from the slots or
openings in its frame or standard. The boat or vessel is suspended to links each
of which engages with one of the bolts 1. The two levers with their bolts are
connected in such a way as to ensure their moving together, so as to prevent one
of the bolts becoming disengaged from the link that carries it unless the other bolt
be at the same time disengaged from its link. In the arrangement under notice,
this connection is in the form of a rod 10 that connects the lower arms of the two
levers. The construction of the bolts 1 will be better understood by referring to
Figs. 2, 3 and 4 which represent to an enlarged scale the construction of the bolt
provided with a lug adapted to a modification hereinafter described. With the
exception of the lug, this bolt is of the same form as those employed in the arrange-
ment illustrated in Figure 1. The upper surface of the bolt is an arc of a circle
whose centre 6 is eccentric to the axis 7 of the pin 8 upon which the lever arm is
mounted and can turn.
The upper side of the slot or hole in the bifurcated frame or standard 3 is an arc
of a circle also struck from the centre 6. The lever fits loosely upon the pin 8 in
such a manner that when the bolts 1 are suspended to links 9 and the weight of
the boat or vessel is thrown upon the bolts, the upper surface of each bolt will take
a bearing against the corresponding surface of the standard or frame which will

page_text: consequently take the weight of the boat instead of its being thrown upon the
pins 8. The eccentric arrangement of the bolt in relation to the axis of the pin
upon which it is mounted has for object to cause the bolt (when relieved of the
weight of the boat or vessel, the link 9 being then lowered out of the recess 4 in
the under part of the bolt) to automatically leave the curved surface of the bifur-
cated standard or frame, thus facilitating outward movement of the bolt 1 to such
an extent as to clear the link 9 and allow it to be raised. However, it is to be
remarked that in some cases it may be found advantageous to mount the bolt
concentrically. In some cases instead of mounting the lever loosely upon the pin,
it may be fixed thereto, the ends of the pin then working freely in holes or bearings
in the standard or frame.
This applies not only to the arrangement already described but to other arrange.
ments to be hereinafter described, in some of which the levers are mounted upon
a shaft.
Figure 5 represents a modified arrangement of apparatus according to my inven-
tion. In this case two levers with hook-like arms, constituting bolts 1, are arranged
one near each end of the boat, and are connected by a rod 10 one end of which is
secured to the hook-like arm of the one lever by a pin 11 passing through an eye in
the rod and through the hole of the lug 12 of the lever (see Fig. 2) whilst the other
end of the connecting rod 10 is attached to the reverse arm 13 of the other lever in
such a manner that the hook-like arm of one lever cannot remove the link with
which it is engaged so as to detach its end of the bolt from the lowering tackle
unless the other hook-like arm becomes in like manner disengaged.
When the boat is water-borne at both ends, the notched hook-like arms of both
levers are by simultaneous movement of the levers upon their fulcra consequent
upon the action of the spring 14 (or of a counter weight or weights in lieu of the
spring) caused to become automatically detached from the lowering tackle.
Figures 6 and 7 illustrate a modification in which the connecting rod 10 is
divided and connected at the centre by a lever 20 having its fulcrum at. 21 and
provided with a counterweight 5. Each portion of the divided rod 10 is connected
by a pin 11 to the lug 12 of one of the hook-like arms formed with the curved
.bolt 1.
Figure 7 illustrates in outline, a torpedo boat with this arrangement of my
apparatus applied thereto.
Figure 8 shows a modification in which the levers are connected by two flexible
connections 10 and 15.
:
One end of each connection is secured to the hook-like arm of one lever, whilst
the other end of the same connection is attached to a reverse arm 13 of the other
lever this arrangement will be readily understood by reference to the drawing
without further explanation. Figure 9 illustrates the application of a fluid con-
nection in lieu of rigid or flexible connections. In this case, the hook-like arnis
formed with curved bolts 1, 1, are provided with counterbalance weights 5 as before,
or springs may be substituted. The lower arms 13 of the levers enter slots or
recesses in rams 16, the respective ends of which work in small hydraulic
cylinders 17, connected by a hydraulic main 18. The counterbalance weights 5,
or equivalent means employed for automatically withdrawing the curved bolts
must be sufficiently powerful to overcome resistance of the movement of the rams 16
in the hydraulic main 18, which, as will be evident, will have the effect of causing
synchronous action of the two bolts and of preventing the movement of the one
bolt without corresponding movement of the other.
Figures 10 and 11 show a modification in which the hook-like arms with curved
bolts 1 are arranged parallel with each other and are rigidly connected by a rod
or bar 10 attached by torsion to prevent one hook-like arm moving without the
other.
10
It is to be understood that standards or frames such as described. with reference
to previous arrangements, though not shown in Figure 10 are. to be used in connec-
tion with the parts therein illustrated. A counter-weight 5 is employed as before

page_text: to automatically move the curved bolts of the lever arms clear of the lowering
tackle. As will be evident in view of a counter weight (or counter weights)
equivalent means such as a spring or springs, may be employed.
Figures 12 and 13 illustrate an arrangement similar to that shown in Figures 10
and 11, but in which a spiral spring 14 is employed in lieu of a counter weight to
automatically move the bolts clear of the lowering tackle. This spring is fastened
at one end to the connecting shaft 10, and at the other end to the deck or other
fixed part of the vessel. The arrangement may be such that partial rotation of the
shaft to move the curved bolts shall result from the tendency of the spring to
unwind or the reverse. As will be evident, however, other arrangements of springs
may be employed, such for example as a tension spring connected to a lever arm
fixed to the shaft 10 as represented in Figures 10 and 11.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I hereby declare that
no general claim is made to the use of detaching apparatus so arranged that when
both ends of a boat or vessel are water-borne, the lowering tackle will become
automatically detached, but that should one end of such boat or vessel become
waterborne whilst the other end remains suspended to and held by the tackle, the
other end will not be released, nor do I claim, broadly, the use of connected hooks
able to turn on pins or pivots and to engage with lowering tackle, but what I do
claim is:
Detaching apparatus for boats and vessels constructed with connected curved
bolts movable about centres and so arranged in relation to correspondingly formed
surfaces in suitable frames, standards or brackets that the weight is taken by the
curved surfaces of the bolts bearing against the corresponding surfaces of the said
frames, standards or brackets, and not by the pins or pivots on which the bolts
turn, as hereinabove described with reference to and illustrated in the drawings
annexed.