Improvements in Submarine Cable Laying Appliances.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in Submarine Cable Laying Appliances.
I, CHARLES SCOTT SNELL of Culver Park, Saltash, in the County of Cornwall,
Engineer do hereby declare the nature of this invention to be as follows:-..
This invention consists in the arrangement of a special intermediate accumulator,
between the main stock of cable carried by the vessel and the sea, through which
the cable passes on its way overboard, and which is capable of receiving or giving out
a certain amount of cable when the speed of delivery overboard does not exactly taliy
with the amount being drawn from the main supply. In conjunction with this
accumulator I prefer to use a special combination of a power operated stern capstan
or drum, to throw the cable overboard for laying with slack at high speed. I may use
also with this combination, a power rotated main drum, or a fixed drum with rotating
arm and pulley which guides the cable around and leads it off the fixed drum.
Of course the ordinary method of cable coiling in tanks may be used in cases where
the special methods may not be desired.
For controlling I prefer to drive the stern drum to the speed required and thereby
pull upon the stock of cable in the accumulator and beyond that upon the store in the
main stock.
The movements, which are set up in the accumulator when differences occur between
the speed of cable delivery, overboard and the rate of paying out from the tank, I may
utilize to control or assist in controlling the accelerating or retarding influence of the
power operating the main drum, when this is operated by power.
This accumulator consists of two drums, in shape as used for capstans or, warping ends
on winches, which are arranged with their axes coincident and separated by a few feet.
Each is loose on its axle, and the cable is wound upon one drum and passed over
an intermediate pulley between the two drums, and thence wound over the second
drum in the reverse direction.
The intermediate pulley is in a plane tangential to the circumference of the drums
and is itself carried by an arm which is fixed to an axle running through the hollow
centre of one of the drum axles. Through this it passes and is provided beyond with
toothed gearing or other connecting mechanism, with "power
"which holds it up to
its position against the stress due to a certain strain on the cable.
If an extra stress is put on, the pulley will be carried round and at each revolution
will take one turn respectively off the adjacent drums. If the stress falls below a
certain point the arm will be rotated by the power applied to it, in the opposite way,
thus putting extra turns upon the drum.
This rotation of the arm can, by suitable gear, be so connected with the link motion'
reversing gear or similar mechanism that the control of the main driving engine can
be effected thereby, thus causing the main drum to set itself to a speed equal to the
demand made upon it by the stern drum.
In regard to this accumulator it is possible to dispense with one drum, but the
movement is not so satisfactory; it is possible to make up a battery of several sets to
hold a large amount of cable, or each drum may be of great length, the end movement
of the cable being facilitated by endless bands upon the periphery, travelling longi-
tudinally as regards the drum axles. These drums if of very large size may have power
applied to rotate them or to assist thereat.

page_text: By this equipment, cable may be paid out at a rate in excess of the vessel's' highest
speed.
Cable can conveniently be wound in from drums on other ships or from depôts
ashore, or for picking up purposes. The "power" applied to the axle of the arm
carrying the intermediate pulley may be derived from a weight or motor or hydraulic
or steam jigger.
The power applied to the stern or main drum may conveniently be either hydraulic,
steam, oil or electric, corresponding appliances being of course used in controlling the
movements as above described.
It is advisable to let the rim of the stern drum have facility for overrunning the
body of the wheel, or an equivalent differential arrangement; and under some
circumstances a ratchet arrangement may be used for preventing its recoiling.
Dated this 13th day of July 1896
proveme
in submarine Cable Laying Appliances.
I, CHARLES SCOTT SNELL of Culver Park, Saltash, in the County of Cornwall,
Engineer, do hereby declare the nature of this invention and in what manner tho
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention consists in the arrangement of a special intermediate accumulator,
between the main stock of cable carried by the vessel and the sea, through which the
cable passes on its way overboard, and which is capable of receiving or giving out a
certain amount of cable when the speed of delivery overboard does not exactly tally
with the amount being drawn from the main supply. In conjunction with this
accumulator I prefer to use a special combination of a power operated stern capstan
or drum, to throw the cable overboard for laying with slack at high speed. I may
use also with this combination a power rotated main drum, or a fixed drum with a
rotating arm and pulley which guides the cable around and leads it off the fixed drum.
Of course the ordinary method of cable coiling in tanks may be used in cases where
the special methods may not be desired.
For controlling, I prefer to drive the stern drum to the speed required and thereby
pull upon the stock of cable in the accumulator and beyond that upon the store in the
main stock.
The movements which are set up in the accumulator, when differences occur between
the speed of cable delivery overboard and the rate of paying out from the tank, I may
utilize to control, or assist in controlling, the accelerating or retarding.influence of
the power operating the main drum, when this is, operated by "power."
This accumulator (see Fig. 1) consists of two drums, in shape as used for capstans
or warping ends on winches, which are arranged with their axes coincident and
separated by a few feet. Each is loose on its axle and the cable is wound upon one
drum, that marked A, and passed over an intermediate pully, B, between the two
drums, and thence wound over the second drum, C, in the reverse direction.
This may be followed by reference also to Fig. 2, similar letters throughout the
drawings referring to similar parts.
The cable, marked D, in this case comes up from the tank or drum below, and is
wound on the drum A, thence around B, and around drum C, emerging at E, where
it is led away.
The intermediate pulley is in a plane tangential to the circumference of the drums,

page_text: and is itself carried by an arm F, which is fixed to an axle G, running through the
hollow centre of one of the drum axles.
Through this it passes, and is provided beyond with toothed gearing or other
mechanism H, with power (see the engine below shown in Fig. 10), which holds it
up to its position against the stress due to certain strain upon the cable.
If an extra stress be put on, the pulley B will be carried around, and at each
revolution will take one turn respectively off the adjacent drums. If the stress falls
below a certain point the arm F will be rotated, by the power applied to it, in the
opposite way, thus putting extra turns upon the drums.
This rotation of the arm can, by suitable gear, be so connected with the link motion
reversing gear or similar mechanism, that the control of the main driving engine
can be effected thereby; thus causing the main drum to set itself to a speed equal to
the demand made upon it by the stern drum.
This may be conveniently effected as shown in Fig. 1. A fine thread upon the
vertical spindle I operates upon a nut J, which is connected by a link with a throttie
valve, in the steam pipe K which feeds the engine. If the cable he not carried on a
large power rotated drum, but on one or more small non-rotating drums, or in an
ordinary cable tank, the steam pipe K may be that leading to an engine arranged to
drive drum A, which, unless considerable power was given to the stern drum, it would
be advisable to equip with an engine to rotate it, or to assist thereat. This may be
seen from Fig. 3, where drum A is fast on a shaft which runs in bearings in the
framing, and is provided with a disc and crank pin L to which the engine is connected,
a brake drum M being also provided. A brake drum may also be affixed to the
other drum C, for convenience under certain contingencies.
In regard to the accumulator it is possible to dispense with one drum, as shown in
Fig. A, but the result is not so satisfactory; it is obviously possible to make up a
battery of several sets, so as to hold a large amount of cable, or each drum may be of
great length, the endway movements of the cable being facilitated by endless bands
upon the periphery, travelling longitudinally as regards the drum axles, see Figs. 5
and 6 which are sections showing bands N, running on pulleys O, mounted
upon lugs P. Engine power, as explained above, may be adapted to rotate, or assist
in rotating, drums.
By this equipment cable may be paid out at a rate greatly in excess of the
vessel's highest speed, and cable can be conveniently wound in from drums in other
ships, or from depôts ashore, or for picking up purposes; as the cable accumulator
forms a flexible link as it were, preventing more than a prearranged stress on the cable.
The "power" applied to the axle of the arm carrying the intermediate pulley may
be derived from a weight or motor or hydraulic or steam jigger. The choice would
be determined by the nature of the auxiliary machinery with which the vessel was
equipped, similarly the power applied to any other part of the mechanism may be
likewise varied, corresponding appliances of course being used in controlling the
movements as above described.
It is advisable to let the rim of the stern drum bave facility for overrunning the
body of the wheel, or an equivalent differential arrangement, and under some
circumstances, such as while the drum is being driven, a ratchet arrangement may
be used to prevent recoiling. Figs. 8 and 9 show a stern drum, which has a rim R,
running on rollers S, and ratchet teeth I, at the side, wherewith a pawl U engages,
this may be thrown out of gear if wished. Thus a sudden stress on the cable is
not affected by the inertia or momentum of a large mass of mechanism and an easy
oscillation of the rim is permitted, where the ship may be "laying to" in a
lively sea.
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:
1st. The construction or combination of parts forming the apparatus referred to
herein as a cable accumulator, substantially as described and illustrated.

page_text: 2nd. The combination of the above with a power rotated drum at the stern of the
vessel, substantially as described and illustrated.
3rd. The application, upon drums forming the accumulator, of longitudinally
travelling bands, substantially as described and illustrated.