Improved Method for Testing the Electrical Firing Gear of Ordnance.
Year: 1891

page_text: Date of Application, 20th Jan., 1891
Complete Specification Left, 19th Oct., 1891-Accepted, 21st Nov., 1891
PROVISIONAL SPECIFICATION.
Improved Method for Testing the Electrical Firing Gear of
Ordnance.
We, ANDREW NOBLE, Companion of the Bath, late Captain of the Royal
Artillery, and EDWARD WILLIAM LLOYD, late Commander in H.M. Navy, both
of Elswick Works, Newcastle-on-Tyne, Engineers, do hereby declare the nature
of this invention to be as follows:-
This invention is to afford a means of automatically informing the gunner when
his gun is ready for firing.
It provides that as soon as the gun is ready for firing, a continuous sound is
made, so that the gunner can hear when all is ready, either by day or night,
without taking his eye from the sighting position. With quick-firing guns, where
it is possible to fire 10, or 15 shots per minute, the delay thus saved becomes
of considerable importance.
Another advantage to be obtained by our system is that the officer in charge
can hear when any gun is loaded and ready for firing, and therefore dangerous to
approach within the limits of range of recoil. The same information is also
conveyed to the gun's crews.
"
We are aware that what are called "detectors
are in use, but these generally
depend for their action on some special electrical connection being made; and,
moreover, they invariably influence a needle or shutter, a system which is open to
the objection that the gunner has to take his eye off his sights before he can see
the indicator, and, moveover, it would be useless in the dark.
Again, previous systems of using "detectors" are open to the objection that
either they are not automatic or that the current passes continuously through
them, and therefore tends to weaken the firing battery; whereas our system is
absolutely automatic, and the current passes only intermittently, and consequently
without injury to the battery.
"
The importance of the "detector system must be beyond dispute if the
following circumstances and properties are taken into consideration :-
It affords a means by which the gunner is informed for certain as to the
effectiveness of his firing gear and primer; so, by its use, warning would always be
given of a miss-fire, and an opportunity of delivering fire (which might decide the
issue of an action) would be guaranteed. It also gives a very ready means of, at
any time before or during practice, testing the efficiency of the electric battery,
the circuit and the primers, which are the only delicate portions of a gun's
installation.
Our invention consists of an automatic electric alarm, the electric current
through which forms a shunt of very high resistance, off the direct firing circuit,
so as to bridge over the firing key. As soon as the tube or primer is inserted in
the gun, and all other contacts made, except that by the firing key, a sound will be
produced, which will be at least loud enough for the firing gunner to hear. This
sound continues until either the gun is fired or some break, other than the firing
key is made.
We usually cause this sound to be produced by an arrangement like a vibrating
electric bell, except that the magnets are wound with a wire of very high
resistance, or that a very high resistance, in conjunction with low resistance
magnets, is placed in the circuit, and that a dome gong may be conveniently
replaced by a steel wire gong. In order to avoid any risk of danger of premature
firing, which might be caused by the saturation with water or some such conductor,
of the electric magnets or other short circuiting of the high resistance, we arrange

page_text: <<
these latter so that, should they be "short circuited," they will also be put to
earth," and thus render it impossible for the battery to fire the gun. We do this
by making metallic connection between the covering or frame-work of the electro
magnets and the gun, so that if the coils of wire are in electric connection with
each other they must also be in connection with the gun, and thus the battery will 5
be short circuited.
To prevent injury to the battery, and as a duplicate safeguard, we sometimes
introduce a cut out either in the shape of a fusible bridge or of an electro magnet.
Dated this 19th day of January 1891.
A. NOBLE.
EDWARD W. LLOYD.
COMPLETE SPECIFICATION.
Improved Method for Testing the Electrical Firing Gear of
Ordnance.
We, ANDREW NOBLE, Companion of the Bath, late Captain of the Royal
Artillery, and EDWARD WILLIAM LLOYD, late Commander in H.M. Navy, both
of Elswick Works, Newcastle-on-Tyne, Engineers, 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 provides a means of automatically informing the gunner when his
gun is ready for firing.
It provides that as soon as the gun is ready for firing, a continuous sound is
made, so that the gunner can hear when all is ready, either by day or night,
without taking his eye from the sighting position. With quick firing guns, where
it is possible to fire 10 or 15 shots per minute, the delay thus saved becomes of
considerable importance.
Another advantage to be obtained by our system is that the officer in charge can
hear when any gun is loaded and ready for firing, and therefore dangerous to
approach within the limits of range of recoil. The same information is also
conveyed to the gun's crews.
In carrying out our invention we apply, in connection with the firing circuit, an
electric sounder so arranged that the electric current through its coils forms a
shunt of very high resistance, off the direct firing circuit, and bridges over the
firing key.
Figure 1 is a diagram showing the ordinary arrangement of the firing circuit.
a is the firing battery connected at one terminal to earth or to the mass of metal of
which the gun is composed and at the other terminal connected with one of the
contact parts of the firing key or pistol at b. cc are sliding contacts which are
brought together in the act of closing the breech of the gun ready for firing; one
of these contacts is electrically connected with the second contact part of the firing
key or pistol and the other is connected through the insulated needle in the breech
block with the primer d of the cartridge which is in place in the gun ready for
firing. Through the primer there is electrical connection with the metal of which
the gun is composed so that when the gun is loaded, the breech is securely locked
and the firing key or pistol contacts brought together, the circuit of the firing
battery is complete. Figure 2 shows how according to this invention, a sounder e¹
is supplied on the firing circuit.
As soon as the tube or primer is inserted in the gun, and all other contacts made,
except that by the firing key, a sound at least loud enough for the firing gunner
to hear is produced by the passage of a current in the firing circuit which current
is sufficient to actuate the sounder but not sufficient to affect the electric primer.
The sound continues until either the gun is fired or some break, other than the
firing key, is made.
We usually cause the sound to be produced by an arrangement such as is shown

page_text: in Figure 3. It is like a vibrating electric bell, except that the magnets are
wound with a wire of very high resistance, or that a very high resistance, in
conjunction with low resistance magnets is placed in the circuit. The resistance
should be at the least 200 ohms and may be as much more as is consistent with the
efficient working of the sounder employed.
In order to avoid any risk of danger of premature firing, which might be caused
by the saturation with water or some such conductor, of the electric magnets or
other short circuiting of the high resistance, we arrange these latter so that, should.
they be short circuited," the current may not pass through the primer, thus
rendering it impossible for the battery to fire the gun. We do this by making
metallic connection between the covering or framework of the electro magnets and
the gun, so that if the coils of wire are in electric connection with each other and
with the covering or casing they must also be in connection with the gun. Both
poles of the battery will then be directly connected with the gun and thus the
battery will be short circuited.
Figure 4 is a diagram illustrating the arrangement; the resistance coils forming
part of or connected with the sounder are contained in a metallic envelope f which
must be equally exposed to water or moisture as the coils forming the shunt circuit.
The envelope is electrically connected with the gun or earth.
To prevent injury to the battery, and as a duplicate safeguard, we sometimes
introduce into the shunt a cut-out either in the shape of a fusible bridge or of an
electro magnet. These appliances if used should be highly sensitive so that in the
case of a powerful current commencing to flow in the shunt they may operate
with certainty to open the shunt circuit before the primer of the cartridge is
affected.
We are aware that what are called "detectors" are in use, but these generally
depend for their action on some special electrical connection being made; and,
moreover, they invariably influence a needle or shutter, a system which is open to
the objection that the gunner has to take his eye off his sights before he can see
the indicator, and, moreover it would be useless in the dark.
"
Again, previous systems of using "detectors are open to the objection that
either they are not automatic or that the current passes continuously through
them, and therefore tends to weaken the firing battery; whereas our system is
absolutely automatic, and the current passes only intermittently, and consequently
without injury to the battery.
The importance of the "detector" system must be beyond dispute if the following
circumstances and properties are taken into consideration.
It affords a means by which the gunner is informed for certain as to the
effectiveness of his firing gear aud primer; so, by its use, warning would always
be given of a missfire, and an opportunity of delivering fire (which might decide
the issue of an action) would be guaranteed. It also gives a very ready means of,
at any time before or during practice, testing the efficiency of the electric battery,
the circuit and the primers, which are the only delicate portions of a gun's
installation.
The arrangement presents the following advantages:-
(a). The information is conveyed to the gunner by sound, so that it is unnecessary
for him to take his eye off his sights and therefore is equally available in light or
darkness.
(b). A ready and simple automatic means is provided of informing the officers
in charge of the gun, the gun's crew or any bystanders, that the gun being ready
for firing is dangerous to approach within limits of recoil or range.
(c). A detector is provided which, owing to the intermittent current which passes
through it, does not lessen the efficiency of the firing battery.
(d). The high resistance shunt circuit cannot be reduced to a low resistance by
becoming saturated with a liquid or by other accidental short circuiting, without
the apparatus being rendered safe as far as firing the gun is concerned.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In the electrical firing gear of ordnance, the combination with the firing
circuit of a high resistance shunt over the firing key or pistol, such shunt including
a vibrating bell or sounder substantially as described.
2. In combination with the subject matter of the preceding claim, the safety
appliances substantially as described.
Dated this 9th day of October 1891
A. NOBLE.
EDWARD W. LLOYD.