Improvements in and relating to Electrically Controlled Submarine Mines.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Electrically Controlled Submarine
Mines.
I, PETER CHRISTIAN FRIEDRICH HOFFMANN, of 7, Wilhelmsplatz, Kiel, in the
Kingdom of Prussia and Empire of Germany, Merchant, do hereby declare the
nature of this invention to be as follows:-
This improved electric submarine-mine installation for blocking harbours and
other water courses, consists of an out-look-hut with its electric switching apparatus,
a dynamo electric machine not specially shown, a submarine casing containing
an electro motor for each mine, as an armature, one or several mines and a con-
ducting cable with branch-conductors connecting each of the submarine electro-
motors as well as each mine, in case the latter are worked electrically.
Euch of the submarine electromotors is located in a water tight compartment
of the casing and has its shaft extending into a second compartment which latter
contains a windlass for the cable of the mine. Upon the motor shaft, in the
interior of the watertight compartment a ratchet wheel is mounted and in the
interior of the second compartment a pinion is arranged, with which the toothed
wheel of the windlass gears. The ratchet wheel works in co-operation with an
electromagnetic pawl. In order to prevent the second compartiment from being
clogged with sand, a pipe is arranged above the opening for the cable; this pipe
lies above the sand level.
By the action of the submarine electromotor the depth of the immersion of the
mine can be regulated from the out-look hut, by causing the motor shaft to rotate
in one or the other direction or to stop. Thus, by rotating the motor, the mine
can be drawn down, subsequently the electric action can be stopped and the mine,
through the medium of the pawl and ratchet wheel device, be retained in its
position, owing to the fact that the pawl falls onto the ratchet wheel, as soon as
the current is interrupted.
On the other hand the mine is caused to ascend, as soon as the motor is turned
in the other direction, thus causing the windlass to rotate in the other direction,
whereby the cable is unwound from the windlass, in which operation the mine
pulls the cable upwards.
As soon as the current is supplied the pawl is caused to recede from the ratchet
wheel by means of the electro-magnet and remains separated from the said wheel,
as long as the current passes.
The mine itself may be constructed in the form of a mechanical or electrical
mine of any kind.

page_text: Improvements in and relating to Electrically Controlled Submarine
Mines.
I, PETER CHRISTIAN FRIEDRICH HOFFMANN, of 7, Wilhelmsplatz, Kiel, in the
Kingdom of Prussia and Empire of Germany, Merchant, 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 present invention relates to improvements in electrically controlled sub-
marine-mines and it consists in certain novel features of construction and com-
binations of parts as will be hereinafter fully described and pointed out in the
claims.
In order that my invention may be more fully understood I will now proceed
to describe the same with reference to the accompanying drawing in which:
Figure 1 is a diagrammatic view of the whole installation;
Figure 2 is longitudinal vertical section of the submarine electromotor and its
casing, drawn to a somewhat larger scale;
Figure 3 is a cross-section on the line I-III (Figure 2).
The improved electric submarine-mine installation for blocking harbours and
other water courses, consists of an out-look-hut A with the electric switching
apparatus of a dynamo electric machine (the latter being not specially shown),
a submarine casing B containing an electromotor for the mine C, and forming
at the same time the anchor of the latter, and conducting cables D leading to the
submarine electromotor or electromotors. In case the mine or mines are exploded
electrically separate conductor cables are provided which lead to the fuse of the
mine.
Each of the submarine electromotors a (Figure 2) is located in a suitable water
tight compartment of the casing B and has its shaft al extending into a second
compartment which latter contains a windlass c for the anchor-cable d of the
mine C. Upon the motor shaft a', within the interior of the watertight compart-
ment b a ratchet wheel is mounted and in the interior of the second compart-
ment ba pinion e is arranged, with which the toothed wheel c' of the windlass
gears. The ratchet wheel works in co-operation with an electromagnetic pawl f¹
(Figure 3). In order to prevent the second compartment from being clogged with
Band, a pipe his attached to the opening for the anchor cable d; the upper mouth
of this pipe lies above the sand level.
By the action of, the submarine electromotor the position or depth of the
immersion of the mine may be regulated from the out-look-hut, by causing tho
motor shaft a¹ to rotate in one or the other direction or to stop. Thus, by rotating a
the motor, the mine may be drawn down, subsequently the electric action may be
stopped and the mine, through the medium of the pawl and ratchet wheel device'f f',
be retained in its desired position, owing to the fact that the pawl f' falls onto
the ratchet wheel f, as soon as the current is interrupted.
On the other hand the mine is caused to ascend, as soon as the motor is turned 4
in the other direction, thus causing the windlass to rotate in the other direction,
whereby the anchor-cable d is unwound from the windlass c, in which operation
the mine has to pull upwards or to lift only the anchor cable and the conductor
connection D', if any, but not to actuate the windlass itself.
As soon as current is supplied the pawl f is caused to recede from or disengage 4
the ratchet wheelf by means of a suitable electromagnet g and remains separated
from the said wheel f, as long as current is supplied.

page_text: The mine itself may be constructed in the form of a mechanical or electrical
mine of any kind and form.
As many changes might be made in the construction and relative arrangement
of the different parts without involving a departure from the gist of my invention,
I would have it understood, that I do not limit myself to the exact construction
shown and described but consider myself at liberty to make such changes and
alterations as fall within the scope of my invention.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:-
1. In an electrically controlled submarino mine the combination of a suitable
mine with anchor cable, an anchor-cable-windlass supported by a suitable anchor
(casing, framing, plate or the like), au electromotor contained in a separate water-
tight compartment of the said anchor and adapted to rotate the windlass in both
directions for winding up and unwinding the anchor cable and a suitable electric
circuit for the electromotor, substantially as and for the purpose set forth.
2. In an electrically controlled submarine mine the combination of a mine
with anchor cable, an anchor-cable-windlass supported by a suitable anchor and
prevented from being clogged with sand by a suitable protecting-casing having
an upwardly extending pipe for the anchor cable, an electromotor contained in
a separate watertight compartment of the said anchor and adapted to rotate the
windlass in both directions for winding up and unwinding the anchor cable and
a suitable electric circuit for the electromotor, substantially as and for the purposes
set forth.
3. In an electrically controlled submarine mine the combination of a mine with
anchor calile, an anchor-cable-windlass supported by a suitable anchor and pre-
vented by suitable means from being clogged with sand, an electro-motor arranged
in a separate watertight compartment of the said anchor, a suitable gearing or
pinion device between the electromotor and the windlass, and an electric circuit
for the electromotor, substantially as and for the purpose specified.
4. The improved electrically controlled submarine mine constructed, arranged
and operating substantially as hereinbefore described with reference to and shown
in the drawing.
Dated this 2nd day of September 1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.