Improvements in Grapnels for Raising Submarine Cables.
Year: 1888

page_text: Date of Application, 17th Aug., 1888
Complete Specification Left, 13th May, 1889-Accepted, 15th June,. 1889
PROVISIONAL SPECIFICATION.
Improvements in Grapnels for Raising Submarine Cables.
I, FRANCIS ROBEert Lucas, of Park Lodge, Hervez Road, Kidbrook, in the.
County of Kent, Engineer, do hereby declare the nature of this invention to be as
follows:-
Grapnels have been designed to cut the bight of the cable when raised and to hold
and bring to the surface one end only but such grapnels as constructed up to the
present time have not worked successfully.
According to my invention I so make the grapnel that the surfaces between which
the cable is held and the blades by which it is cut are forced together by the strain
upon the lifting rope so that the greater the strain the more surely is the cable held
and the more certainly is it cut.
The way I prefer to construct the grapnel is as follows :-
At the lower end of the shank are fixed two projecting prongs or hooks. Two arms
are hinged to the shank so that when turned outwards they are at right angles to the
hooks and as the grapnel is dragged along the bottom act like the stock of an anchor
and keep one or other hook on the ground so as to ensure its catching the cable.
These arms are so connected to the lifting rope that the strain upon it tends to fold
them down along the shank but the arms are kept extended by a bolt or fastening
which only gives way under a certain predetermined strain.
The ends of the arms
and also the lower end of the shank are fitted with sheaves.
A rope is led round these sheaves, and the ends are passed up through the shank
which is made hollow terminating at the top in an eye into which is shackled the
lifting rope.
When the bight of the cable is hooked by one of the prongs, and the grapnel is
being raised off the bottom, an increasing strain is brought on the rope above
mentioned, this in time becomes sufficient to break the bolt which keeps the arms
extended, the latter immediately fold downwards and firmly clamp the cable between
the sbank and their under surfaces. These surfaces are formed with corrugations
which correspond with corrugations on the shank and so increase the grip by bending.
the cable out of the straight line.
Knives or cutting devices are fitted to diagonally opposite corners of the lower end
of the shank one opposite to the bottom of each hook and corresponding knives are
fixed to the ends of the hinged arms, in such a manner that a further increase of
strain on the rope, as the lifting proceeds, forces one or other of the pairs of knives
together on to the cable cutting it through and dropping one end, the other end being
firmly held and brought to the surface.
Dated th: 171 1
A 1000
COMPLETE SPECIFICATION.
Improvements in Grapnels for Raising Submarine Cables.
I, FRANCIS ROBERT LUCAS, of Park Lodge, Hervez Road, Kidbrook, in the County
of Kent, 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 :-
Grapnels have been designed to cut the bight of the cable when raised and to hold
and bring to the surface one end only but such grapnels as constructed up to the
present time have not worked successfully.
According to my invention I so make the grapnel that the surfaces between which

page_text: the cable is held and the blades by which it is cut are forced together by the strain
upon the lifting rope so that the greater the strain the more surely is the cable held
and the more certainly is it cut.
The grapnel as I prefer to construct it is shown in side and end elevation at
Figures 1 and 2.
At the lower end of the shank a are fixed two projecting prongs or hooks bb. Two
arms c c are hinged to the shank so that when turned outwards they are at right
angles to the hooks and as the grapnel is dragged along the bottom act like the stock
of an anchor and keep one or other hook on the ground so as to ensure its catching
the cable. These arms are so connected to the lifting rope that the strain upon it.
tends to fold them down along the shank but the arms are kept extended by a
bolt or fastening d which only gives way under a certain predetermined strain. The
ends of the arms and also the lower end of the shank are fitted with sheaves e e
and respectively.
A rope g is led round these sheaves, and the ends are passed up through the shank
which is made hollow terminating at the top in an eye l'into which is shackled the
lifting rope.
When the bight of the cable is hooked by one of the prongs, and the grapnel is
being raised off the bottom, an increasing strain is brought on the rope above men-
tioned, this in time becomes sufficient to break the bolt d which keeps the arms c c
extended, the latter immediately fold downwards and firmly clamp the cable between
the shank and their under surfaces as shown in dotted lines. These surfaces are
formed with corrugations which correspond with corrugations on the shank and so
increase the grip by bending the cable out of the straight line.
Knives or cutting devices are fitted to diagonally opposite corners of the lower
end of the shank one opposite to the bottom of each hook and corresponding knives kk²
are fixed to the ends of the hinged arm, in such a manner that a further increase of
strain on the rope, as the lifting proceeds, forces one or other of the pairs of knives
together on to the cable cutting it through and dropping one end, the other end being
firmly held and brought to the surface.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. Grapnels in which the surfaces between which the cable is held and the blades
by which it is cut are forced together by the strain upon the lifting rope.
2. Holding the surfaces and blades out of action by a bolt or other part which gives
way under a predetermined strain.
3. Grapnels substantially as described and shown in the drawings.
CARPMAEL & Co.,
Agents for the Applicant.