AN IMPROVED INSTANTANEOUS BOAT DISENGAGING APPARATUS
Year: 1882

page_text: LETTERS PATENT to Charles Mace and John Brewster both of Sunderland
in the County of Durham, Engineers for an Invention of AN IMPROVED
INSTANTANEOUS BOAT DISENGAGING APPARATUS
PROVISIONAL SPECIFICATION left by the said Charles. Mace and John
Brewster at the Office of the Commissioners of Patents on the 1st September
1882.
CHARLES MACE and JOHN BREWSTER both of Sunderland in the County
of Durham, Engineers
'AN IMPROVED INSTANTANEOUS BOAT DISENGAGING
APPARATUS"
«
The object of our invention is to afford increased facilities in disengaging
ship's boats from the tackle hooks by which they are suspended from the "davits
ensuring unfailing and instantaneous action at both ends by gear which is strong
and simple requiring no skilled hand to release the boat at any time.
We fit each end of the boat with a strong box shaped frame attached by a double
eye or socket to a "stanchion" (which is secured to the keel) and bolted to the
underside of the "thwart" or seat. In the upper part of this box frame is formed
a cross recessed opening with a double eye at one end, fitted with a strong crossbar,
suitably shaped to receive the tackle hook, the other end of the box frame
being fitted with a sliding block or carriage (which we prefer) fitted with rollers to
prevent friction. The inner end of this carriage is fitted with a roller which
travels over and holds down the end of the crossbar when the boat is hanging in
the tackle hooks but when operated by the hand gear it slides back and releases
the crossbar which flies up, on its hinged end in the double eye, and the boat is
free of the hook, the action being instantaneous at both ends at the same moment.
The operating gear consists of levers taking hold of double eyes on outer end of
each sliding block and having their fulcrumos carried in brackets on underside of
box frames. These levers are connected to a rod which runs from end to end in
bottom of boat, in such a way that on the rod being moved in either direction both
the sliding blocks are either drawn out of or forced into the box frame (running
upon their rollers) at one moment, the boat being released from the tackle hooks
by one movement and the crossbar held down ready to attach to the tackle hooks by
the other movement. This connecting bar or rod is operated at any convenient
position in the boat by a hand lever working in a bracket fixed to the keel, the
short arm of the lever forming a sector working into a rack on the top of bar or
connected to the bar by bridle links or other suitable appliance.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Mace and John Brewster in the Great Seal Patent Office
on the 1st March 1883.
CHARLES MACE and JOHN BREWSTER both of Sunderland in the County of
Durham Engineers AN IMPROVED INSTANTANEOUS BOAT DISENGAGING APPARATUS
"
The object of our invention is to afford increased facilities in disengaging ships
boats from the tackle hooks by which they are suspended from the "davits
ensuring unfailing and instantaneous action at both ends by gear which is strong
and simple requiring no skilled hand to release the boat at any time
We fit each end of the boat with a strong box shaped frame attached by a double
eye or socket to a "stanchion" (which is secured to the keel) and bolted to the
underside of the "thwart" or seat. In the upper part of this box frame is formed
a cross recessed opening with a double eye at one end, fitted with a strong crossbar
suitably shaped to receive the tackle hook, the other end of the box frame being
fitted with a sliding block or carriage (which we prefer) fitted with rollers to
prevent friction. The inner end of this carriage is fitted with a roller which
travels over and holds down the end of the cross bar when the boat is hanging in
the tackle hooks but when operated by the hand gear it slides back and releases
the crossbar which flies up, on its hinged end in the double eye, and the boat
is free of the hook, the action being instantaneous at both ends at the same
moment. The operating gear consists of levers taking hold of double eyes on
outer end of each sliding block and having their fulcrums carried in brackets
on underside of box frames. These levers are connected to a rod which runs from
end to end in bottom of boat, in such a way that on the rod being moved in either
direction both the sliding blocks are either drawn out of or forced into the box
frame (running upon their rollers) at one moment, the boat being released from the
tackle hooks by one movement and the crossbar held down ready to attach to the
tackle hooks by the other movement. This connecting bar or rod is operated at
any convenient position in the boat by a hand lever working in a bracket fixed to
the keel, the short arm of the lever forming a sector working into a rack on the top
of bar or connected to the bar by bridle links or other suitable appliance
The accompanying drawings illustrate the manner in which our invention may
be carried into practical use though we do not confine ourselves to the details of
operating mechanism. The same letters refer to corresponding parts on all the
Figures
Figure 1 shews a boat hanging from the "davits" by the tackle hooks A. A'. are
box shaped frames at fore and aft ends of the boat bolted to underside of
"thwarts" or seats B. B¹. and attached by stanchions C. C. to the keel piece;
D. D are crossbars hinged on pins E E' and curved upward so as to take the
tackle hooks F F¹ The free ends of the hinged crossbars D D¹ are held down in
position by rollers G G₁ carried in the ends of sliding carriages H H' which work
upon friction rollers J J' in the box shaped frames A A¹ being moved to and fro by
levers K K having their fulcrums in brackets cast upon or attached to the
frames A A' The lower ends of these levers are attached by rods L L' running
along the keel of the boat to a hand lever M (having its fulcrum in a bracket N
bolted to keel) to which they are connected so that a movement of the lever will
operate the rods L L' in opposite directions and through the levers K K', will draw

page_text: back the sliding carriages H H₁ so as to release the free ends of the hinged cross-
bars D D the weight of the boat and its crew causing them to fly up and slip the
tackle hooks F Ft
Figure 2 shews the hand lever M moved (in the direction of the arrow on
Figure 1) the sliding carriages H H¹ being drawn back and with them the'
roller G G¹ the hinged crossbars D D₁ being shewn open and the boat free to fall
into the water
Figure 3 shews a plan of the boat with the gear and the recesses O O' in the
thwarts (provided for the ready attachment of the tackle hooks) by means of
which recesses nothing is left projecting above the thwarts when the boat is dis-
engaged. When the boat is required to be again attached to the tackle hooks the
hinged crossbars are closed down and a reverse movement of the hand lever
forces forward the sliding carriages the end rollers of which pass over and hold
down the free ends of crossbars to which the tackle hooks being attached as in
Figure 1 the boat is ready for being lifted up to the "davits." The hand lever M
may be made to lie down in bottom of boat by having a joint in it so as to hinge
back. The levers K K' may be operated by a toothed sector and a rack but we
prefer the mode described as simplifying the action.
Having now fully described and illustrated our invention we claim as the novel
feature secured to us by Letters Patent
The application of sliding carriages operated by gearing from within the boat,
to set free hinged cross bars and instantaneously disengage the boat from the tackle
hooks substantially as shewn and described
In witness whereof I the said John Brewster on behalf of myself and the
said Charles Mace have hereunto set my hand and seal this twenty eighth
day of February in the year of our Lord one thousand eight hundred and
eighty three
Witness:
T. J. DANSON F. Inst. P. Agents
Consulting Engineer & Patent Agent
Newcastle on Tyne
JOHN BREWSTER (L.S.)