IMPROVEMENTS IN APPARATUS FOR DISENGAGING BOATS FROM LOWERING TACKLE AND FOR DISENGAGING HOOKS TO BE USED FOR THIS AND OTHER PURPOSES
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by William Lowrie and John Anthony
Rowe at the Office of the Commissioners of Patents on the 8th December
1881.
WILLIAM LOWRIE of Newcastle upon Tyne and JOHN ANTHONY ROWE of
North Shields. "IMPROVEMENTS IN APPARATUS FOR DISENGAGING BOATS FROM
LOWERING TACKLE AND FOR DISENGAGING HOOKS TO BE USED FOR THIS AND
OTHER PURPOSES."
According to this Invention we construct a disengaging hook in the following
manner. To one end of a bar which is suspended or supported vertically we joint
a curved hook-the hook extends through an arc of about two thirds of a circle.
When the weight of a boat or other weight is being supported on or by the hook
the portion of the bent hook on which the weight rests is vertically in a line with
the bar or nearly so and the end of the hook extends somewhat beyond this point
so that as long as the weight is on the hook there is no tendency for the book to
get detached from the weight but on the contrary the weight tends to keep the
hook from shifting its position. The end of the bar is also formed with a curved
nose extending from it through an are of about one third of a circle in the opposite
direction to the stem of the book so that the end of the hook abuts against the
end of the nose and the book and nose together form an entire ring.
The bar to which the hook is jointed bas also jointed to it at a distance from
the point where the hook is jointed to it a link or lever arm which at its extremity
is by a connecting rod jointed to the hook at a point midway of its length.
Preferably the length of the lever arm and the distance between the axis of the
hook and the point at which the connecting rod is jointed to it is such that the
connecting rod is kept parallel or nearly so with the bar, the link and stem of the
hook being also parallel with one another like the links of a parallel ruler.
In boat disengaging mechanism two such disengaging hooks are used one forward
and the other aft of the boat. When the boat disengaging mechanism is to act
automatically the bar of cach disengaging hook is by a rod descending from it
attached hook uppermost to the keel of the boat; in this position the weight of the
hooks and the rods connected to them tends to turn the hooks into their open
position. The two disengaging hooks are so connected together that if one hook

page_text: opens the other must open also. Preferably we effect this in the following manner.
The link or lover arm of one hook we prolong beyond the joint where it is jointed
to the bar and we couplo it by a rod to an arm on one end of an axis which is
parallel with the keel of the boat and capable of turning in bearings carried by it.
The connecting rod of the other hook we by a rod descending from it connect to an
arm on the opposite end of the axis.
The action of the disengaging gear is as follows:-If a boat is hanging by the
fore and aft disengaging hooks to rings or hooks at the ends of the lowering
tackles the weight of the boat keeps the hooks in their closed position but when
the boat has been lowered and is water borne at both ends so that the hooks have
no weight hanging upon them the connecting rod of each disengaging book drops
by its own weight or by a weight attached to it and turning the hooks frees the
boat from the lowering blocks. If the bont is water borne at one end only the
hooks would not disengage as unless both hooks are free neither one or other can
turn.
When the disengaging gear is to be hand controlled instead of the disengaging
hooks being supported hook upwards by rods from the keel of the boat they are
suspended hook downwards from the lower blocks of the davits. In this position
the hooks normally remain closed and the boat is suspended to them by the
ordinary boat rings:
The after and forward hooks are in this case connected by a small steel wire or
strong rope which can be set up or slacked back as occasion may require. A
trigger line is attached to a lever arm on the link or lever of the aft disengaging
hook. When the boat is being lowered the coxswain takes this line in his hand
and on nearing the water puts a steady strain upon it. Whilst the weight of the
boat is on the hooks it will be impossible for the pull on the line to alter the
position of the hooks but as soon as the boot is water borne the tension on the
trigger line will cause both hooks to open together and release the bout.
Disengaging hooks constructed as above described may also be used for towing
and other purposes.