Improvements in Cartridges to be Fired by Electricity.
Year: 1899

page_text: Date of Application, 31st May, 1899
Complete Specification Left, 28th Feb., 1900-Accepted, 26th May, 1900
PROVISIONAL SPECIFICATION.
Improvements in Cartridges to be Fired by Electricity.
We, WILLIAM FRIESE-GREENE, of 39, King's Road, Chelsea, in the County of
London, Photographer, and PERCY EDWIN KNELL, of 8, Pope's Road, Brixton,
in the same County, Engineer, do hereby declare the nature of this invention
to be as follows:-
Our invention has reference to cartridges to be fired by electricity and either
for large or small guns, or for blasting or other purposes where great and sudden
power is required.
A characteristic feature of the invention is that no explosive in the ordinary
sense of the term is employed.
According to our invention we employ as the charge some material which
resists the passage of electricity and owing to such resistance becomes vaporized
either instantaneously or more or less quickly as may be required according to
the object to be obtained, say on the one hand for a gun cartridge or on the
other hand for a blasting cartridge. As materials suitable for the purpose we
may mention magnesium, lead, and lead alloys and they may be employed in
the form of twisted wire, shavings or otherwise. The said material constitutes
part of the electric circuit. The case or part of the case of the cartridge is
formed of insulating material and the two poles of the battery are connected
respectively with the two ends of the charge so that when the circuit is completed
the current passes through the charge and vaporizes it.
In applying the invention to a gun cartridge for example the case would pre-
ferably be made entirely of insulating material and the bullet be connected to
the front end of the case while the rear of the case could be fitted with a metal
plate; the charge would form an electric connection between the bullet and the
said plate and these would in turn be connected respectively with the two poles
of the battery.
In some cases we may enclose compressed air or gas within the cartridge in
addition to the charge above described in order to increase the force developed.
Dated this 31st day of May 1899.
Improvements in Cartridges to be Fired by Electricity.
We, WILLIAM FRIESE-GREENE, of 39, King's Road, Chelsea, in the County of
5 London, Photographer, and PERCY EDWIN KNELL, of 8, Pope's Road, Brixton,
Price Sd} 1

page_text: in the same County, 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:-
Our invention has reference to cartridges to be fired by electricity and either
for large or small guns, or for blasting or other purposes where great and sudden
power is required.
A characteristic feature of the invention is that no explosive in the ordinary
sense of the term is employed.
According to our invention we employ as the charge some conducting material
which resists the passage of electricity and owing to such resistance becomes
vaporised either instantaneously or more or less quickly as may be required
according to the object to be attained, say on the one hand for a gun cartridge
or on the other hand for a blasting cartridge. As material suitable for the
purpose we may mention magnesium, lead, tin and lead or tin alloys, and they
may be employed in the form of twisted wire, shavings or otherwise. The said
material at the time of firing constitutes part of the electric circuit. The case
or part of the case of the cartridge is formed of insulating material and the two
poles of the battery are connected respectively with the two ends of the charge
so that when the circuit is completed the current passes through the charge and
vaporizes it.
In applying the invention to a gun cartridge for example the case would pre-
ferably be made entirely of insulating material and the bullet be connected to
the front end of the case while the rear of the case could be fitted with a metal
plate the charge would form an electric connection between the bullet and the
said plate and these would in turn be connected respectively with the two poles
of the battery.
In some cases we may enclose compressed air or gas within the cartridge in
addition to the charge above described in order to increase the force developed.
In the accompanying drawings,―
Figure 1 is a longitudinal central section of a blasting cartridge constructed
according to our invention.
Figure 2 is a cross section on the line A-1 of Figure 1.
In these figures,-1 is the case of the cartridge; it is made of insulating
material such as vulcanized fibre. 2 is the charge consisting of a number (seven
are shown) of twisted strips or wines of magnesium or other suitable material
arranged longitudinally in the cartridge and insulated from one another by
partitions 3 of insulating material. These partitions are most conveniently made
by forming the cartridge case of a solid block of insulating material and mould-
ing or boring therein holes 4 into each of which a length of magnesium wire is
inserted leaving space for air in connection with each of said lengths. Each
length of magnesium wire is electrically connected at its rear or inner end to a
screw-threaded stud which extends through the base 2 of the cartridge to
the rear of the latter where it is connected electrically to one end of an insulated
conducting wire 6. A small plate 7 into which each stud 5 is screwed is inserted
in the inner end of each hole 4 and serves to hold the said stud in position. All
the insulated wires 6 are connected at their other ends at a common junction 8
to a common terminal 9. The outer ends of the magnesium wires 2 are elec-
trically connected to a common metal plate or disc 10 which serves to close
in the outer ends of the holes 4 in the cartridge case. A wire 11 electrically
connected at one end to the plate 10 is led through the insulating material of the
cartridge case to the rear end of the latter where the said wire terminates in a
terminal 12.
To explode the cartridge the two poles of an electric battery are connected
respectively through the terminals 9 and 12 with the two ends of the charge so
that when the circuit is completed by means of a firing key the current passes
through the charge and vaporizes it.

page_text: Figure 3 is a longitudinal central section of a gun cartridge in position in a
gun, only so much of the latter being shown as is necessary to show the applica-
tion of our invention.
Figure 4 is a cross section on the line C-D of Figure 3.
In the gun cartridge shown in these figures, the construction of the case and
the arrangement of the charge are substantially the same as in the cartridge
shown in the preceding figures, but the plate 10 of the said previous figures is
replaced by an equivalent part 10 which constitutes the base of a projectile 13.
14 represents the breech end of the gun. 15 represents the breech block or an
equivalent part. In this case the studs 5 are not connected to wires such as 6,
but end in contact heads 16. 17 is a plate or disc adapted to slide freely in the
breech end of the gun. It carries a number of insulated studs 18 which are
formed with contact heads 19 projecting from the outer or front face of the
plate 17 and each adapted to make electrical contact with one of the studs 5 in
the base of the cartridge. Each stud 18 is electrically connected at its rear end
to an insulated conducting wire 20 which is led through a perforation 21 in the
breech block 15. The breech block is screw threaded and engages with screw
threads 22 formed in the breech of the gun, so that when the breech block is
screwed home, an effective electrical contact will be made between the contacts 16
and 19.
The wires 20 are connected at a common point 23 to a commion wire 24 form-
ing part of the circuit of an electric battery 25. The circuit is completed from
the contacts 16 through the magnesium wires 2, the base 10 of the projectile 13
and the projectile itself, through the metal of the breech end 14 whence the
current is conveyed by means of a wire 26 back to the battery 25. 27 represents
an electric firing key. To prevent the cartridge moving forwards in such a
manner as to break the contact between the parts 16 and 19, the base of the
cartridge is made with a flange 28 which engages with a shoulder 29 in the
breech of the gun.
When a more or less gradual, in contradistinction to a sudden, vaporization
is desired the wires or lengths 2 in the same cartridge may be made of different
resistances to the passage of a current of electricity and this can conveniently
be effected by making the said wires or lengths of different thicknesses.
Figure 5 is a central longitudinal section, and Figure 6 is a cross section on
the line E F of Figure 5, of a modified form of cartridge for blasting purposes.
In this form a circular base 30 of insulating material carries a number (six are
shown) of rod-shaped conductors 31 of good conducting non-vaporizable metal
such as brass spaced equally apart in a circle around the centre of the base. One
half (three) of these rods 31 are connected by means of wires 32 at a common
point to one terminal 33, and the other half of the rods are similarly connected
by wires 34 to an opposite terminal 35. The rods are preferably connected
alternately according to their poles, so that any two adjacent rods are of opposite
poles, as is clearly shown in Figure 6.
The charge is composed of volatilizable metal strip or wire 36 coiled in an
open coil around the circular skeleton support constituted by the rods 31 as
shown; or it may be composed of a number of thin discs of volatilizable metal
threaded on the rods 31 at suitable distances apart.
37 is an
The conductors 31 which, if desired, may be made in any convenient form
other than rod-shaped as shown, act as supports for the charge, but their chief
purpose is to convey the firing current to all parts of the charge 36 at one and
the same instant so that the whole of the charge is exploded at once.
outer case of insulating material; it may form part of, or be a separate piece
attached to the base 30. 38 is a thick disc of insulating material for closing
the end of the cartridge case. 39 is a disc of insulating material through which
the terminals 33 and 35 pass out to the exterior of the cartridge; it has for
object to prevent short-circuiting of the rods 31 when making contact for firing.
Figure 7 is a central longitudinal section illustrating a gun cartridge of the

page_text: 40 is the
type just described in position in a gun arranged to fire the same.
cartridge case of insulating material carrying in its forward end the bullet 41.
30 is the base of insulating material in which the rod-like conductors 31 are
fixed. 36 is the charge of volatilizable metal coiled around the rods 31. The
rods 31 are connected electrically together in two groups in the manner shown
in Figure 5, to two common terminals 42 and 43 respectively. 39 is the insulat-
ing disc on the base of the cartridge as herein before described.
Figure 8 is a separate view of the front face of the breech lock 44 which is
pivoted at 45 to the underside of the gun. The breech block carries two contact
pieces 46 and 47 which are insulated from each other and from the breech block
and which are adapted to make electrical contact respectively with the ter-
minals 42 and 433 of the cartridge when the breech block 44 is closed as shown in
Figure 7. 48 is a projection formed on the cartridge and adapted to fit in a
notch provided in the edge of the gun breech; it has for object to ensure that the
cartridge shall be inserted in the gun with the terminals 42, 43 in the proper
corresponding positions to the contact pieces 46 and 47 in the breech block.
The contact pieces 46, 47 pass out to a firing key and battery (not shown) through
a plate 49 which is carried by the breech block 44 and which serves to take the
pressure of the breech screw 50. The breech screw is provided with operating
handles or levers 51 and works in a cross bar 52 which is pivoted in the ends of
two links 53, that are pivoted at their other ends on trunnions 54 on either side
of the breech of the gun.
To load the gun, the breech screw is unscrewed to a sufficient extent to enable
it with the cross bar 52 and links 53 to be turned up on top of the gun, and the
breech block 44 to be turned down to allow a cartridge to be inserted into the
gun. The breech block is then turned up again and the breech screw turned
down and screwed in against the plate 49 so as to press the contact pieces 46, 47
well into electrical contact with the ends of the rod terminals 42, 43 of the cart-
ridge. The gun is now loaded and ready for firing by operating the firing key.
Having now particularly described and ascertained the nature of our said
invention and in what maner the same is to be performed, we declare that what
we claim is:-
1. In a cartridge to be fired by electricity a charge comprising a metal which
is vaporisable more or less quickly by the passage therethrough of a current of
electricity whereby explosive energy is generated, substantially as hereinbefore
described.
2. In a cartridge to be fired by electricity the combination of a case of in-
sulating material, a length of conducting material within said case and vaporiz-
able more or less quickly by the passage of electricity therethrough space for
air within said case and means at separate parts of said case for making electric
contact with said conducting material at the respective ends thereof whereby on
the passage of a current of electricity through said conducting material explosive
energy is generated, substantially as herein before described.
3. In a cartridge to be fired by electricity, the combination of a case of insu-
lating material, lengths of conducting material which is vaporizable more or
less quickly by the passage of a current of electricity therethrough, said lengths
being insulated from one another and forming the charge in said case, a common
terminal, or contact piece connected to one end of all the said lengths and a
common terminal or contact piece connected at one common point to all the said
lengths, substantially as herein before described.
+. In a cartridge to be fired by electricity the combination of a case of insu-
lating material, lengths of conducting material which is vaporizable more or
less quickly by the passage of a current of electricity therethrough, said lengths
offering different resistance to said passage, being insulated from one another
and forming the charge in said case, a common terminal or contact piece con-
nected to one end of all of said lengths and a common terminal or contact piece

page_text: connected at one common point to all the said lengths, substantially as herein-
before described.
5. In a cartridge to be fired by electricity, conductors carried by the case, in
combination with a charge of conducting material which is vaporizable more or
less quickly by the passage of a current of electricity therethrough, one group
of conductors being connected with one terminal and the other group of con-
ductors being connected with the other terminal, substantially as and for the
purpose described with reference to Figures 5, 6 and 7 of the accompanying
drawings.
Dated this 27th dor of Fabr 1000
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.