Improvements in Ships' Davits.
Year: 1893

page_text: Date of Application, 28th Apr., 1893
Complete Specification Left, 28th Feb., 1894-Accepted, 25th Apr., 1894
PROVISIONAL SPECIFICATION.
Improvements in Ships' Davits.
I, RICHARD ROPER, of Palace Chambers, 9 Bridge Street, Westminster, in
the County of Middlesex, Marine Contractor and Engineer, do hereby declare the
nature of this invention to be as follows:-
This invention relates to Improvements in Ships' Davits.
A davit constructed according to my invention consists of a vertical standard of
trough-like section in which is mounted free to rotate a vertical screw spindle
extending nearly the whole length of the standard. To the bottom of the standard
is pivoted an arm of about the same length as the standard and which when turned
on its pivot into a vertical position lies against the standard and partially within
the open side of the same so as to enclose the screw spindle and form a fourth
side to the standard so that it presents the appearance of being square in section.
A nut is fitted upon the screw spindle and pivoted to a link which is in turn
pivoted to the pivoted arm already described. It will be seen that a vertical
movement given to the nut by the rotation of the screw spindle will turn the
arm upon its pivot to or from the vertical standard. A suitable folding link is
provided to limit the outward movement of the pivoted arm. The free end of
this arm carries a pulley over which a rope is passed to suspend the boat. This
rope passes down the arm over suitable guiding pulleys and through the deck to a
winding drum placed beneath the same.
I connect each pair of davits by means of bevelled gearing so that their screw
spindles may be rotated simultaneously and in the same direction and both ends of
the boat lowered at the same rate. For the purpose of this connection a shaft or
spindle runs longitudinally beneath the deck from one davit to another. For the
same purpose I wind the rope from each davit upon the same drum.
It will be seen that by the outward movement of the pivoted arm the boat is
moved away from the sides of the vessel until it is in such a position that it may
be lowered into the water.
This form of davit is particularly useful where the boats are stowed upon the
rails of a ship.
CASTLE SMITH,
Invention" Office, 54, Fleet Street, London, E.C.,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Ships' Davits.
I, RICHARD ROPER, of Palace Chambers, 9 Bridge Street, Westminster, in the
County of Middlesex, Marine Contractor and 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 :-
This invention relates to Improvements in Ships' Davits.
A davit constructed according to my invention consists of a vertical standard of
trough-like section in which is mounted free to rotate a vertical screw spindle
extending nearly the whole length of the standard. To the bottom of the standard
is pivoted an arm of about the same length as the standard and which when
turned on its pivot into a vertical position lies against the standard and partially
within the open side of the same so as to enclose the screw spindle and form a
fourth side to the standard so that it presents the appearance of being square in
Го .
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page_text: section. A nut is fitted upon the screw spindle and pivoted to a link which is in
turn pivoted to the pivoted arm already described. It will be seen that a vertical
movement given to the nut by the rotation of the screw spindle will turn the arm
upon its pivot to or from the vertical standard. A suitable folding link is provided
to limit the outward movement of the pivoted arm. The free end of this arm
carries a pulley over which a rope is passed to suspend the boat. This rope passes
down the arm over suitable guiding pulleys and through the deck to a winding
drum placed beneath the same.
I connect each pair of davits by means of bevelled gearing so that their screw
spindles may be rotated simultaneously and in the same direction and both ends
of the boat lowered at the same rate. For the purpose of this connection a shaft
or spindle runs longitudinally beneath the deck from one davit to another. For
the same purpose I wind the rope from each davit upon the same drum.
It will be seen that by the outward movement of the pivoted arm the boat is
moved away from the sides of the vessel until it is in such a position that it may
he lowered into the water.
And in order that my invention may be more fully understood.and carried into
practice I will now proceed to describe the same with reference to the accompanying
drawings, of which Figs. 1 and 2 are a side and front elevation respectively of
a davit constructed and operated according to my invention, and Fig. 3 a side
elevation of a slightly modified form thereof.
A vertical standard a of trough-like section is secured to or near the rail or
other portion of the side of the vessel and has mounted in suitable bearings thereon
a vertical screw-threaded spindle b extending nearly from end to end of said
standard.
To the bottom of said standard a is pivoted an arm c of about the same length
as said standard and which when turned on its pivot into a vertical position lies
against the standard and partially within the open side thereof so enclosing the
spindle b and forming the fourth side of the standard. An internally threaded
nut & fits on to the spindle b and is connected by pivoted or hinged links e to
the arm c thus when the spindle is revolved the nut will be caused to travel
thereon and either raise or lower the arm c, the movement of which is limited
preferably by folding links f connecting said arm and the standard a together.
The free end of the arm c carries a pulley situated preferably to one side of the
axes of said arm and over this a rope from which the boat is suspended is passed.
This rope then passes down said arm over suitable guide pulleys through the deck
to the drum of a windlass secured in any suitable position and around which the end
of a similar rope extending from the other davit of the pair is also wound.
The vertical spindles of each pair of davits I gear together so that they may be
operated simultaneously by gearing them by gear wheels g to a common shaft h
mounted in suitable bearings preferably parallel to the ship's rail and operated
from handle through bevel gears and shaft m mounted in bearings in supports
or casing n or the like.
In the modified form of davit illustrated in Fig. 3 the pivoted arm c has its
upper end curved but in all other respects the construction and mode of operating
it is the same.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is : :-
Davits constructed and operated substantially as described and illustrated in the
accompanying drawings
lay of February 1894.
CASTLE SMITH,
Office of "Invention," 54, Fleet Street, London, E.C.,
Agent for the Applicant.