US 6,745,697 B2 · Cartridge

Abstract

A cartridge with a propellant case (4) that contains a propellant charge (3) and an electrothermal ignition device, wherein several ignition channels (9) are provided in the charge (3), and extend axial-symmetrical in the direction of longitudinal axis (8) of cartridge (1), with each channel comprising a propellant tube (10) and an electrically conducting layer (11). To achieve a uniform and symmetrical ignition of the cartridge (1) in the chamber of the respective weapon, electric arcs (21) that form during the ignition operation in the ignition channels (9), are decoupled in that the electrically conducting layer (11) is composed of successively connected rhombi or other shapes (circles, ovals, etc.) that electrically function as decoupling resistances. When current flows through such a structure, the current bridges (20) arranged in the current-flow direction between the individual rhombi (15) etc. initially break apart explosively. Electric arcs (21) then are formed at these locations and are decoupled by the decoupling resistances (15). Continued current flow causes more and more of the decoupling elements (15) to erode, so that the electric arcs (21) become longer and longer.

Drawings

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Drawings

Claims10

Dependent claims

A cartridge comprising:

a combustible case containing a charge and an electrothermal ignition device including
a plurality of ignition channels provided in the charge, and extending axial symmetrical in the direction of a longitudinal axis of the cartridge, and with
each ignition channel comprising at least a first propellant tube that is provided on at least one of an inner and an outer surface with an electrically conducting layer that extends in the direction of the longitudinal axis of cartridge, and that is connected at its opposite ends to a respective electrode for connecting each of the electrically conducting layers across a power supply;
and wherein each
electrically conducting layer has a structure that forms at least one series connection of a plurality of electrical decoupling resistances interconnected by high resistance bridging elements, and each of the decoupling resistances has a geometrical shape and makes a point contact, as a bridging element, with adjacent resistances in a respective series connection, whereby following the activation of a power-supply system connected across the electrodes, current flowing through the structure causes several electric arcs to form between adjacent decoupling resistances as a result of local overheating in the bridging elements.

2 more elements

Dependencies are inferred from the claim text.

Description1,916 words

Summary851 words

#This application claims the priority of German Patent Application No. DE 101 40 599.5 filed Aug. 18, 2001, which is incorporated herein by reference.

#The invention relates to a cartridge with a combustible cartridge case containing a propellant charge and an electrothermal ignition device or igniter.

#In order to ignite the propellant powder of known cartridges with an electrothermal ignition device, an extremely high current is allowed to flow through a wire conductor in the bottom region of the respective cartridge, which is high enough to cause an explosive vaporization, of the wire thus generating an energy-rich electric arc. The electric arc then ignites the respective propellant powder.

Brief description of the drawings7 figures

#FIG. 1 is a longitudinal section through an exemplary embodiment of a schematically represented cartridge according to the invention, which has six ignition channels that are connected to a power-supply system.

#FIG. 2 is an enlarged cross section through the cartridge shown in FIG. 1, along the line II—II therein.

#FIGS. 3-5 are schematic representations of an electrically conducting structure, arranged horizontally in the plane and consisting of three rows of rhombus-shaped regions, such as can be arranged in the ignition channel of the cartridge according to the invention. The structure is shown prior to the ignition operation in FIG. 3 and at two different points in time after the start of the ignition operation in FIGS. 4 and 5.

Detailed description846 words

#Reference 1 in FIG. 1 refers to a large-caliber cartridge (e.g. to be fired from a tank weapon), which is connected to a power-supply system 2 for the ignition. The respective weapon in which the cartridge 1 is located is not shown for reasons of clarity.

#The cartridge 1 comprises a case 4, consisting of a combustable material, that is filled with a propellant charge 3, as well as a case bottom 5 of metal that closes off the propellant case 4 on the bottom side.

#A high-voltage electrode 6 is arranged in the center of case bottom 5, with the electrode 6 being insulated relative to the case bottom 5 and being connected to a metal disk 7 that functions as a current distributor and is disposed in the casing 4.

Facts

Application

10/222,871Filed 19 Aug 2002

Priority

DE 101 40 59918 Aug 2001

Published

US 2003/0033953 A120 Feb 2003

Granted

8 Jun 2004

Term ended

19 Aug 2022

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification5 codes

F42B 5/181
Caseless ammunition; Cartridges having combustible cases: consisting of a combustible casing wall and a metal base; Connectors therefor
F42B 5/08
Cartridges, i.e. cases with charge and missile: modified for electric ignition
F42C 19/12
Primers ; Detonators: electric
F42B
Explosive charges

Cartridge

Life of this patent

Cartridge

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims10

Description1,916 words

Drawings

Classification5 codes

Life of this patent

Description1,916 words