Disposable, miniature internal optical ignition source for ammunition application

Patent metadata

Field	Value
Publication number	US-9618307-B1
Application number	US-201615007575-A
Country	US
Kind code	B1
Filing date	Jan 27, 2016
Priority date	Mar 28, 2013
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

An ammunition cartridge for a gun is optically initiated by a mechanism wholly within the cartridge case itself. The case has as optical primer initiation means producing light fluence to ignite a primer, which ignited primer may in turn ignite into a flashtube, and which ignited flashtube may in turn ignite a bed of propellant in said cartridge. The optical primer initiation means may be an LED, a laser diode, a VCSEL, or some other light emitting device in general. The cartridge optically initiated primer package is so sized and made electrically and mechanically seamlessly physically compatible with current ammunition cartridges such that these new cartridges are completely interchangeable. If the cartridge primer initiation means is of a percussion type, the cartridge is adapted to include an in-line piezoelectric crystal so that electrical power will be generated when the cartridge assembly is struck by a firing pin during percussion type operations; the power is then used to initiate the light emitting device.

First claim

We claim:

1. A primer assembly for an optically initiated ammunition cartridge comprising: a primer; and an optical primer initiator configured for producing light fluence to ignite said primer and wherein the optical primer initiator further comprises a laser diode mounted on an integrated circuit such that the output of the laser diode is perpendicular to a mounting surface of the integrated circuit, the laser diode is manufactured such that a light fluence outputs from a front surface of the laser diode and a top surface and a bottom surface comprise conductive connections of the laser diode and wherein the optical primer initiator further comprises a first flexible contact arm and a second flexible contact arm for supporting the laser diode on the integrated circuit and providing electrical connections to the integrated circuit.

2. The primer assembly of claim 1 wherein each of the first flexible contact arm and the second flexible contact arm comprises a conductive tab with a laser contact area and a circuit contact area and wherein the laser contact area and circuit contact area are perpendicular to each other.

3. The primer assembly of claim 2 wherein the conductive tab is a copper material.

4. The primer assembly of claim 2 wherein the flexible contact arm further comprises a flexible support supporting the conductive tab.

5. The primer assembly of claim 4 , wherein the flexible support is a polyimide material.

6. The primer assembly of claim 4 wherein the flexible contact arm further comprises thermally plated conductive holes through the flexible support at the laser contact area.

7. An optically initiated ammunition cartridge for a gun, comprising: a brass cartridge case comprising a projectile element, a bed of propellant, a flashtube embedded in said bed of propellant, and a primer assembly to initiate said propellant, said primer assembly comprising a primer, a primer button and a brass cup, and having an optical primer initiation means producing light fluence to ignite said primer, which ignited primer in turn ignites into said flashtube, and which ignited flashtube in turn ignites said bed of propellant and wherein the optical primer initiator further comprises a laser diode mounted on an integrated circuit such that the output of the laser diode is perpendicular to a mounting surface of the integrated circuit.

Assignees

• Us Army

Inventors

• Redington Stephen
• Macrae Christopher
• Burke Gregory
• Hirlinger John

Classifications

• F42C19/0823 Primary

  Primers or igniters for the initiation or the propellant charge in a cartridged ammunition (primers for caseless ammunition F42C19/085) · CPC title

• F42B5/08 Primary

  modified for electric ignition · CPC title

• F42B5/28

  of metal {, i.e. the cartridge-case tube is of metal} · CPC title

• B23K1/0016

  Soldering of electronic components · CPC title

• F42C19/0807

  characterised by the particular configuration of the transmission channels from the priming energy source to the charge to be ignited, e.g. multiple channels, nozzles, diaphragms or filters · CPC title