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Publication numberUS667435 A
Publication typeGrant
Publication dateFeb 5, 1901
Filing dateDec 30, 1899
Priority dateDec 30, 1899
Publication numberUS 667435 A, US 667435A, US-A-667435, US667435 A, US667435A
InventorsWilliam Friese-Greene, Percy Edwin Knell
Original AssigneeWilliam Friese-Greene, Percy Edwin Knell
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Cartridge fired by electricity.
US 667435 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Patented Feb. 5, I90l. W. FRIESE-GREENE & P. E. KNELL.


Wnesses v I iizveyz/fizy m 2/1, Jo Mu/ UNITED STATES PATENT OFFICE.




SPECIFICATION formingpart of Letters Patent No. 667,435, dated February 5, 1901. Application filed December 30, 1899. Serial Ila 7 12,160 (No model.)

To aZZ whom it may concern:

Be it known that we, WILLIAM FRIESE- GREENE, of 39 Kings road, Chelsea, London, and PERCY EDWIN KNELL, of 8 Popes road, Brixton, London, England, have invented certain new and useful Improvements in Cartridges to be Fired by Electricity, of which the following is a specification.

This 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 this invention we employ as the. charge some metal which upon the passage of electricity through an electric circuit of which it forms part becomes vaporized 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 guncartridge or, on the other hand, for a blastingcartridge. As materials suitable for the purpose we may mention magnesium, lead, and lead ortin alloys, and they may be employed in the form of twisted wire, shavings, orotherwise. The said material at the time of firing constitutes part of the electric circuit.

In some cases we may inclose 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 longitudinalcentral section of a blasting-cartridge constructed according to our invention. Fig. 2 is a cross-section on the 'lineA B of Fig. 1. Fig. 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 application of our invention. Fig. 4 is a cross-section on the line C D of Fig. 3.

Referring to Figs. 1 and 2, 1 is the case of the cartridge. It is made of insulating ma terial, such as vulcanized fiber. 2 is the charge, consisting of a number (seven are shown) of twisted strips or wires 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 cartridgecase of a solid block of insulating material and molding or boring therein holes 4, into each of which a length of magnesium wire is inserted, leaving space for connection with each of said lengths. Zach length of magnesium wire is electricalIy connected at its rear or inner end to a screw-threaded stud 5, 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 atacommon junction 8 to a common terminal 9. The outer ends of the magnesium wires 2 are electrically connected to a common metal plate or disk 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. Toexplode the cartridge, the two poles of an electric battery are connected, respectively through the terminals 9 12, with the two ends of the charge, so that when the circuit is completed the current passes through the charge and vaporizes it.

In the gun-cartridge shown in Figs. 3 and 4 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 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 diskadapted to slide freely in the breech end of the gun. It carries a number of insulated studs'lS, 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 througha perforation 21 in the breech-block 15. The breechblock 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 elfective electrical contact will be made between the contacts 16 and 19. The wires 20 are connected at acorn mon point 23 to a common wire 24, forming part of the circuit of an electric battery 25. The circuit is completed from the contacts 16 through the megnesium 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 firingkey. To prevent the cartridge moving forward 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 ofthe gun.

When-a more or less gradual (in coutradistinction 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 efiected by making these of difierent thicknesses.

What we claim, and Letters Patent, is

1. In a'cartridge to be fired by electricity a charge consisting solely of a metal which is Vaporizable more or less quickly by the passage therethrough of a current of electricity whereby explosive energy is generated, substantially as set forth.

2. In a cartridge to be fired by electricity desire to secure by the combination of a case of insulating material, a length of metal within said case, said metal being vaporizable more or less quickly by the passage of electricity therethrough, andmeans at separate parts of said case for making electric contact with said vaporizable metal at the respective ends thereof whereby on the passage of a current of electricity through said metal explosive energy is generated, substantially as set forth.

3. In a cartridge to be fired by electricity, the combination of a case of insulating material, lengths of metal 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 set forth.

4. In a cartridge to be fired by electricity the combination of a case of insulating ma terial, lengths of metal vaporiz'able more or less quickly by the passage of a current of electricity therethrough, said lengths oiier-'

Referenced by
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US2553477 *Feb 6, 1948May 15, 1951Charles SchermulyDischarger for rockets, flares, and the like
US3492688 *Jun 16, 1966Feb 3, 1970Physics Int CoApparatus for tenderizing food
US4275858 *Sep 25, 1978Jun 30, 1981The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern IrelandPanel breaking systems
US4907487 *Nov 12, 1986Mar 13, 1990Gt-DevicesApparatus for and method of accelerating a projectile through a capillary passage and projectile therefor
US4957035 *Apr 12, 1989Sep 18, 1990Rheinmetall GmbhElectrothermal acceleration device
US5033355 *Jan 27, 1986Jul 23, 1991Gt-DeviceMethod of and apparatus for deriving a high pressure, high temperature plasma jet with a dielectric capillary
US5042359 *Apr 12, 1989Aug 27, 1991Rheinmetall GmbhProjectile accelerating device
US5094141 *Aug 22, 1991Mar 10, 1992Diehl Gmbh & Co.Arrangement for accelerating a projectile through a plasma
US5115743 *Jun 12, 1990May 26, 1992Tzn Forschungs- Und Entwicklungszentrum Unterluss GmbhPropellant casing assembly for an electrothermic projectile firing device
US5331879 *Oct 1, 1992Jul 26, 1994Tzn Forschungs-Und Entwicklungszentrum Unterluss GmbhElectrothermal firing device and cartouche for use in such devices
US5924278 *Apr 3, 1997Jul 20, 1999The Board Of Trustees Of The University Of IllinoisPulsed plasma thruster having an electrically insulating nozzle and utilizing propellant bars
US5988070 *Sep 29, 1998Nov 23, 1999Rheinmetall W & M GmbhPlasma injection device for an electrothermal gun
US6142056 *Apr 8, 1998Nov 7, 2000U.T. Battelle, LlcVariable thrust cartridge
US6295804Oct 21, 1998Oct 2, 2001The Board Of Trustees Of The University Of IllinoisPulsed thruster system
US8746120Oct 19, 2012Jun 10, 2014The United States Of America As Represented By The Secretary Of The NavyBoosted electromagnetic device and method to accelerate solid metal slugs to high speeds
US8810121Oct 19, 2012Aug 19, 2014United States Of America As Represented By The Secretary Of The NavyMethod and device to produce hot, dense, long-lived plasmas
US9534858 *Oct 15, 2012Jan 3, 2017The Commonwealth Of AustraliaCartridge and system for generating a projectile with a selectable launch velocity
US9534863 *Oct 29, 2012Jan 3, 2017The United States Of America, As Represented By The Secretary Of The NavyElectromagnetic device and method to accelerate solid metal slugs to high speeds
US9618306 *Oct 8, 2015Apr 11, 2017Safariland, LlcMunition with unexploded ordnance limiting
US20090188626 *Oct 23, 2008Jul 30, 2009Xinpei LuPlasma jet device
US20150159981 *Oct 15, 2012Jun 11, 2015The Commonwealth Of AustraliaCartridge and System for Generating a Projectile with a Selectable Launch Velocity
US20160102954 *Oct 8, 2015Apr 14, 2016Safariland, LlcMunition with Unexploded Ordnance Limiting
Cooperative ClassificationF42B5/10