Improvements in Boat Lowering Tackle.
Year: 1891

page_text: Date of Application, 16th Oct., 1891
Complete Specification Left, 16th Aug., 1892-Accepted, 1st Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in Boat Lowering Tackle.
I EDWARD JACOB HILL of 11 Victoria Street in the City of Westminster
Engineer do hereby declare the nature of this invention to be as follows:-
My invention relates to improvements in the boat lowering gear forming the
subject of previous Letters Patent dated April 16 1891 No. 6579 whereby the
lowering of the boat is effected by means of special blocks and falls supplementary
to the ordinary multiple purchase tackles used for raising the boat.
My first improvement has for its object to enable the distance through which
the boat may be lowered to be increased without increasing the space required
inboard by the handing tackle which it is desirable should not exceed the distance
between the davits. This I effect by giving the supplementary falls a multiple
purchase for instance by attaching them to a fixed point and passing them round
sheaves which are moved by and may be mounted in the running block of the
handing tackle.
My second improvement is designed to prevent the fouling of the supplementary
falls with the boat raising tackle and this I effect by mounting the sheaves over
which the supplementary falls pass at the davit-heads in such a position that their
centres are out of line with the point of suspension from the davit head and with
the point of suspension from their blocks of the standing blocks of the boat raising
tackle, so that the latter will be swung to one side out of the way when the strain
comes on the supplementary falls.
My third improvement is designed to enable the rings by which the running
blocks of the boat raising tackle are connected to the hooks of the boat, to be dis-
connected from the said running blocks when the boat is to be lowered by the
supplementary fails, and it consists in connecting the said rings to the said running
blocks by open hooks instead of by closed eyes, as before.
Dated the 16th day of October 1891.
EDWARD JACOB HILL,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Boat Lowering Tackle.
I, EDWARD JACOB HILL of 11 Victoria Street, in the City of Westminster,
Engineer, do hereby declare the nature of this invention and in what mauner
the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
My invention relates to improvements in the boat-lowering gear forming the
subject of previous Letters Patent dated April 16th 1891 No. 6579 whereby the
lowering of the boat is effected by means of special blocks and falls, supplementary
to the ordinary multiple purchase tackles used for raising the boat.
My first improvement has for its object to enable the distance through which the
boat may be lowered to be increased without increasing the space required inboard
by the handing tackle which it is desirable should not exceed the distance (on
deck) between the davits. This I effect by giving the supplementary falls a
multiple purchase by attaching them to a fixed point and passing them round
sheaves which are moved by and may be mounted in the running block of the
handing tackle.

page_text: My second improvement is designed to prevent the fouling of the supplementary
falls with the boat raising tackle, and this I effect by mounting the sheaves over
which the supplementary falls pass at the davit-heads in such a position that their
centres are out of line with the point of suspension from the davit heads and with
the point of suspension of the standing blocks of the boat-raising tackle so that the
said standing blocks and consequently the tackles will be swung to one side out of
the way when the strain comes on the supplementary falls in lowering.
My third improvement is designed to enable the rings by which the running
blocks of the boat raising tackle are connected to the hooks of the boat, to be dis-
connected from the said running blocks when the boat is to be lowered by the
supplementary falls, and it consists in connecting the said rings to the said running
blocks by open hooks instead of by closed eyes as before.
Reference is to be had to the accompanying drawings, forming part of this Speci-
fication, wherein
Figure represents a boat suspended by the supplementary falls, ready to be
lowered thereby.
Figure 2 is a side view of one of the. davit heads, shewing more clearly the
position assumed by the standing block of the hoisting tackle when the strain comes
on the lowering tackle.
Figure 3 is a similar view shewing the relative position of the standing block of
the hoisting tackle and the block of the lowering tackle when hoisting.
Figures 4 and 5 shew two forms of hook for detachably connecting the hoisting
and lowering rings with the running blocks of the hoisting tackle.
The same letters of reference denote like parts in all the figures.
A A are the ordinary multiple purchase davit tackles to be used for hoisting
the boat, B¹ being the standing blocks and B' the running blocks thereof. CC'are
the supplementary "falls" passing over special sheaves e at the davit heads and
over guide sheaves hereafter referred to, through a sister block D, the two ends of
the falls C C being made fast to a fixed point e'. It will be observed that the
fall C passes over two guide sheaves c² before reaching the sister block D
whereas the fall C¹ passes over three guide sheaves c', c², and c³, before reaching
the same point.
Through the other sheaves of the sister block D passes a multiple purchase
tackle E which passes round a sheave or sheaves e attached to the one davit or to
a convenient point near the same on the bulwark or deck. This tackle may have
any proper amount of purchase, and in lowering the sister block D travels between
the position in which it is shewn and the fixed point et which is situated at or near
the other davit. The sheaves c at the davit heads are mounted in blocks F
suspended at from the davit heads and from whose lower ends the standing
blocks B' are suspended at f the centre of the sheave c being out of line with the
points of attachment so that when the strain is on the sheave c, as in Figures 1
and 2, the point" will be out of the vertical plane with point and the centre of
sheave c and consequently the block B' and the tackle A dependent therefrom will
be swung aside out of the way and will not be liable to foul the supplementary
falls in lowering. Similarly in hoisting, the supplementary falls are out of the
way of, and will not foul, the hoisting tackle, as shewn in Figure 3.
The rings G by which either the running blocks B2 or the supplementary
falls CC are attached to the hooks. H of the boat for the purpose of hoisting or
of lowering the boat as the case may be, are each permanently connected to its
supplementary fall by an eye g and detachably connected to the running block B*
of the hoisting tackle, by a hook g' which may be either outwardly or inwardly
curved, as shewn in Figures 4 and 5, so that in lowering the boat the hoisting
tackles A are not only swung automatically to one side by the action of the davit-
head blocks F as above described but whilst still using the same rings G both for
hoisting and lowering, the tackles A may be disconnected and brought inboard, as
shewn, so as to be quite clear of the men or crew being lowered in the boat.
The hooks H are preferably of the construction described in former Patents

page_text: Nos. 12968 of 1888 and 3313 of 1890, but may be of any other approved
construction.
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. In the herein described boat lowering tackle, the combination, with the
supplementary lowering falls, of the multiple purchase handing tackle arranged
and operating substantially as specified, the said falls being made fast to a fixed
point and reeved through sheaves carried by a running sister block or its equivalent,
moved by the handing tackle.
2. In the herein described boat lowering tackle, mounting the sheaves over
which the supplementary falls pass at the davit heads in such position in the blocks
from which the hoisting tackle blocks are suspended as to cause the latter to be
swung clear of the lowering falls when the strain comes on them as specified.
3. In the herein described boat-lowering tackle, the employment, in combination
with supplementary lowering falls passing over sheaves so mounted as to cause the
hoisting tackle to be swung clear, in the manner described, of rings connected to
said falls and adapted to be detachably connected to the running blocks of the
hoisting tackle, as and for the purpose specified.
Dated this 16th day of August 1892.
E. J. HILL,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.