Improvements in the Construction of Submarine Grapnels.
Year: 1889

page_text: Date of Application, 28th Nov., 1889
Complete Specification Left, 14th Jan., 1890-Accepted, 15th Mar., 1890
PROVISIONAL SPECIFICATION.
- Improvements in the Construction of Submarine Grapnels.
I HENRY BENEST of the Telegraph Works, Silvertown in the County of Essex,
Telegraph Engineer, do hereby declare the nature of this invention to be as
follows:-
The object of this invention is to provide a grapnel which will not merely hook a
submerged cable, but will grip or hold the same fast when hooked.
The advantages of such a grapnel are manifest, inasmuch as there will be no
slipping of the cable on the flukes, and if a loose end is caught, it cannot escape
from the grapnel.
The invention admits of modification, but the essential feature is the conversion
of the flukes into automatically acting gripping jaws. The stem or shank of the
grapnel is fitted with a boss which forms a guide for leading the hooked cable into
the position to be gripped. Below this boss the shank is fitted with a thick plate
carrying forked extensions standing out radially for the reception each of a fluke
which is pivotted thereto. These flukes may be described as bell crank levers, the
short arms of which are intended to receive the pressure of the cable as it is caught,
and thus cause the flukes which are in action to rise from their open position an
close upon the cable, and grip it against the boss of the grapnel.
By this arrangement it will be understood that the act of hauling in the grapnel
will have a tendency to increase the grip of the grapnel upon the cable which it
has caught.
As a modification of the invention, I may use pairs of gripping surfaces, pivotting
a pawl-shaped jaw to the forked plate in front of each gripping fluke, and con-
necting the two together by spur gearing; thus, when a cable is caught and the
grapnel is being bauled in, there will be a simultaneous approach of the two gripping
surfaces to each other, and a quick grip (with no tendency of the cable to slip) will
be ensured.
D
11
201
1
1000
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Construction of Submarine Grapnels.
I HENRY BENEST of the Telegraph Works, Silvertown in the County of Essex,
Telegraph 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:-
The object of this invention is to provide a grapnel which will not merely hook a
submerged cable, but will grip or hold the same fast when hooked.
The advantages of such a grapnel are manifest, inasmuch as there will be no
slipping of the cable on the flukes, and if a loose end is caught, it cannot escape
from the grapnel.
The invention admits of modification in its application, but the essential feature
of the invention is the conversion of the flukes into automatically-acting gripping
jaws.
In the accompanying drawings, I have shown my improved grapnel in two
forms, the grip being obtained in the one between moving and fixed jaws, and in
the other by pairs of moving jaws.
Fig. 1 shews in side elevation a grapnel of the simpler form. Fig. 2 is a plan

page_text: view of the same as seen from above. Fig. 3 is a plan view as seen from below,
and Fig. 4 is a portion of the grapnel shewing one of the flukes in the gripping
position.
This
A is the stem or shank of the grapnel, which carries at its lower end a boss B
conveniently made of cast steel, and secured to the stem A by a lock nut.
boss is ribbed, as at b, to form inclined shoulders, which constitute the fixed
gripping jaws of the grapnel. Below these ribs, the boss extends laterally, forming
five forks, which serve as supporting arms for the pivotted flukes C. These
flukes, which are pointed at their outer ends and form the pivotted gripping jaws,
take somewhat the shape of a hell-crank lever, that is to say, their rear ends extend
inwards beyond the centre of motion of the fluke, and when depressed, cause the
upper part of the fluke to advance towards the fixed gripping surfaces to which
they are respectively opposed.
с
The upper surface c of the tail end of the fluke is intended to receive the cable
which is underrun by say two of the flukes C.
As the cable caught by the grapnel, while being drawn over the sea bottom,
slides over the flukes, it will be caused to press upon the surface c of the tail
end of the fluke, and by so pressing, to tip the fluke into the position of Fig. 4,
by which means the cable will be automatically gripped between the fluke C and
the boss B of the grapnel.
On the hauling in of the grapnel, the bite on the cable will be not only maintained,
but increased, and thus the tendency of the cable to slip, even though a loose end
only is caught, will be removed.
In some cases, however, where, for example, the hauling in is, from circumstances
beyond the seaman's control, irregularly continued, the grapnel, by dropping, may
lose hold of the partially raised cable, which, on getting above the level of the fluke
pivots, will have no tendency to remain within the grasp of the grapnel.
It is to avoid this that the modification which I will now describe is devised.
Fig. 5 shews in side elevation, partly in section, my improved automatic grapnel
fitted with a locking device, and Fig. 6 is a plan view of the same.
In this arrangement, instead of using the fixed gripping surfaces b forming part
of the boss B (Fig. 1), I provide a second movable jaw D, which, like the fluke C,
is pivotted within the supporting arms extending horizontally from the boss B.
The jaws D are severally connected with their respective flukes C by interlocking
teeth, which ensure the simultaneous approach of the jaws C and D, to grip the
cable when the pressure of the booked cable comes upon the surface c of the tail of
the flukes.
Each jaw D is slotted longitudinally to receive a locking pawl d and a tumbler d'
situate below the pawl, and designed to move it into its locking position and retain
it therein. These pieces d d are pivotally connected to the jaw D, and the
end of the pawl, when in its locking position, enters a nick in the gripping face of
the fluke C.
The tumbler is so formed that, when not in action, its lower end will project
somewhat from the gripping face of the jaw D, as shewn on the left hand side of
Fig. 5.
This is for the purpose of enabling the cable, as it slides in between the gripping
surfaces, to tip the tumbler D¹, and thereby bring into position the locking pawl d,
as shown at the right hand side of Fig. 5.
In order that the cable, whilst being hooked, may not be caught and lodge upon
the top of the jaw piece D, the cast boss is formed with a web which projects so
as to cover said jaw piece.
It will now be understood that the cable caught by the grapnel, and brought
within the grip of the jaws C, D, will be effectually prevented from escaping there-
from until released by hand after the recovered cable is suitably secured.
. It will be obvious that the number of flukes may vary, but in all cases it is
desirable that there should be an uneven number of flukes, to ensure the bringing
of two to operate simultaneously upon a cable lying across the path of the grapnel.

page_text: Having now particularly described and ascertained the nature of my
invention and in what manner the same is to be performed, I declare that what I
claim is :-
-―
1st. The arrangements of automatically acting grapnels above described with
reference to the accompanying drawings.
2nd. The conversion of the flukes of the grapnel into automatically acting gripping
jaws, as above set forth.
Dated this 13th day of Jenner 1800.
NEWTON & SON,
Agents for the Applicant.