An Improvement in Boat-lowering Tackle.
Year: 1889

page_text: Date of Application, 29th Nov., 1889
Complete Specification Left, 29th Sept., 1890-Accepted, 1st Nov., 1890
PROVISIONAL SPECIFICATION.
An Improvement in Boat-lowering Tackle.
I, EDWARD JACOB HILL, of 11 Victoria Street, in the City of Westminster, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to an improvement in boat lowering tackle; and has for its
object to provide a tackle whereby the boat may be lowered with greater rapidity and
certainty so as to reach the water either on an even keel or with the stern slightly
lower than the bow.
Heretofore, in all boat raising and lowering tackles, it has been usual to both
raise and lower the boat by the same pair of tackles, and, in order that the boat
may be raised with the necessary ease, multiple purchase tackles are used by means
of which a gain in power is obtained at the expense of speed and conditionally on
the handling (i.e. hauling in) long lengths of rope such comparative slowness of
motion and length of running ropes being incidental to the lowering, as well as to
the hoisting, of the boat.
The object of my invention is to overcome these disadvantages in lowering, and I
accomplish this result by combining with each of the ordinary multiple purchase
tackles a supplementary simple block and fall, the use of the former being restricted
to the raising of the boat and of the latter to the lowering of the boat, and I further
combine with the said supplementary falls an improved contrivance whereby the
necessary simultaneity of descent of the two ends of the boat is ensured and
accidents, such as now happen when the two tackles are controlled by different men
and paid out at different rates of speed, are avoided.
In carrying out my invention, I provide in or near the upper or standing block
of each of the ordinary tackles an additional sheave over which and over suitable
guide sheaves on the davits the supplementary falls are led, said falls being attached
at their inboard ends to, and winding on, a barrel common to both. This barrel is
provided with flanges forming grooves in which the respective falls are wound, the
width of the grooves being only equal to the diameter of the rope so that each fall
must necessarily coil upon itself, the diameter of the barrel thus virtually decreasing
as the falls are unwound. The said barrel has a third groove in which is wound a
third rope (which I will distinguish as the handing rope) attached to the barrel and
winding on a part of the barrel which is by preference of larger diameter than the
other two parts, this rope winding on in the inverse direction to the other two so
that as the the latter wind off the former winds on and conversely.
If the boat is to be lowered on an even keel, the falls would be wound equally
on the barrel but if the boat is to be started to lower on an even keel and yet the
stern end reach the water before the bow end, the stern fall would be coiled upon
its part of the barrel one or several turns more than the other fall.
When it is required to lower the boat, the outboard ends of these falls are
respectively made fast to the eyes or rings which are commonly attached per-
manently to the lower or running blocks of the ordinary tackles and which for the
purposes of my invention are made detachable therefrom and with this object are
preferably provided each with two eyes or loops one for the attachment of the
corresponding supplementary fall and the other for connection to the running block.
The supplementary falls having been attached and the ordinary tackle detached, the
lowering is performed by means of the former under the control of the handing rope
which winds on the barrel as the falls unwind therefrom the gradually increasing
power of control due to the oppositely varying virtual diameters of the barrel enabling

page_text: the tendency to an acceleration of speed of descent of the boat to be easily checked
as it nears the water.
Dated this 29th day of November 1889
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.
COMPLETE SPECIFICATION.
An Improvement in Boat-lowering Tackle.
I, EDWARD JACOB HILL of 11, Victoria Street, in the City of Westminster, Civil
Engineer, 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 :-
My invention has for its object to provide a boat-lowering tackle whereby
the boat may be lowered with greater rapidity and certainty so as to reach the water
either on an even keel or with the stern slightly lower than the bow, as may be
preferred.
Heretofore, it has been usual to employ the same pair of tackles both for raising
and for lowering the boat, the said tackles affording what is termed a multiple
purchase whereby a gain in power is obtained at the expense of speed and conditionally
on the handling (that is, hauling in or paying out) of long lengths of rope. The
consequent slowness of motion of the boat and the great length of the running ropes
which are incidental to the use of the same tackles, both for hoisting and for
lowering the boat, constitute a disadvantage in the latter operation which it is the
object of my invention to avoid.
1 accomplish this result by combining with each of the ordinary multiple purchase
tackles a supplementary simple block and fall, the use of the former being restricted
to the hoisting, and of the latter to the lowering of the boat, and I further combine
with the said supplementary falls an improved contrivance whereby the necessary
simultaneity of descent of the two ends of the boat is ensured and accidents resulting
from the two tackles being separately controlled and paid out at different times or
speeds are avoided.
Reference is to be had to the accompanying drawings, forming part of this Speci-
fication, wherein
Figure 1 is an elevational view from inboard of one of the davits shewing the end
of the boat suspended therefrom and the controlling gear for the lowering gear of
both davits.
Figure 2 is an end view of the same.
Figure 3 shews a three-sheave standing block which may be used for the purpose
of my invention.
"
The same letters of reference indicate like parts in all the figures.
In carrying out my invention, I provide in or near the upper or standing"
block A of each of the ordinary multiple purchase tackles B an additional sheave a.
This additional sheave may either be mounted as a separate block or may be one of
the sheaves of an ordinary block, such as that shewn in Figure 3, in addition to
those required for the ordinary multiple purchase tackle. Over this additional
sheave, and over suitable guide sheaves c on the davit C, the supplementary fall D
is led, each of said supplementary falls D D1 being attached at the inboard end to,
and being wound on a barrel E common to both. This barrel E is provided with
flanges forming grooves e e¹ in which the respective falls D D¹ are wound, the width
of the grooves being only equal to the diameter of the rope so that each must
necessarily coil upon itself, the diameter of the barrel thus virtually decreasing as
the falls are unwound. The said barrel has a third groove f in which is wound a
third rope F (which I will distinguish as the handing rope) the part of the barrel

page_text: on which this rope winds and to which it is attached being, by preference, of larger
diameter than the other two parts, this rope F winding on in the inverse
direction to the other two D D₁ so that as the latter wind off the former winds on
and conversely.
If the boat is to be lowered on an even keel, the falls D D' would be wound
equally on the barrel but if it is desired that the stern end of the boat shall reach
the water before the bow end, notwithstanding that the boat before being lowered
is on an even keel, the stern fall D would be coiled upon its part of the barrel one
or several turns more than the other fall D³.
When it is required to lower the boat the outboard ends d of these falls are
respectively made fast to the eyes or rings 9 which are commonly attached per-
manently to the lower or running blocks G of the ordinary multiple purchase tackles.
For the purposes of my invention, these eyes g are connected to the blocks G by
shackles so as to be detachable therefrom and they are preferably provided with two
eyes or loops, the one h for the attachment of the corresponding supplementary
fall D and the other i for connection to the running block G. The supplementary
falls D D having been attached to the eyes h and the ordinary tackles B detached
from the eyes i, the lowering is performed by means of the falls D D' under the
control of the barrel E and the handing rope F which winds on the barrel as the
falls D D unwind therefrom, the varying virtual diameters of the barrel affording a
gradually-increasing power of control which enables the tendency to an acceleration
of speed of descent of the boat to be easily checked, as it nears the water.
The running of the handing rope F would of course be checked by coiling it about
bitts or by any form of friction device commonly used for the purpose.
Instead of the handing rope F, a friction brake might be applied directly to the
drum E.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is;
1. The employment, in combination with boat davits and in addition to the ordinary
multiple purchase tackles, of simple falls passing over supplementary sheaves and
coiled on and controlled by the same drum, substantially as and for the purpose
specified.
2. In the herein described boat lowering gear, the combination, with the
supplementary falls, of a grooved drum on which the falls and the handing rope are
constrained to coil on themselves so as to vary the effective diameter of the drum
and so increase the power of control, as specified.
LXICO ΕΠΙΚ
1
U
of September 1000
2006
FALCO HILLS UNLY U
E. J. HILL.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.