EXPLOSIVELY DRIVEN FRAGMENT LAUNCHER AND A METHOD FOR EXPLOSIVELY LAUNCHING A FRAGMENT AT A TARGET

Abstract

Disclosed techniques relate to fragment launching. In an example, a fragment launcher has a casing, a launch aperture and a detonation position. An inner profile of the casing tapers from the main body towards the fragment launch aperture and from the main body to the detonation position. A fragment is held within the launch aperture such that when in use an explosive charge can be initiated to launch the fragment from the launcher. The launcher is particularly suited to uses where there is a requirement to launch a fragment in a consistent and repeatable manner.

Claims

1. An explosively driven fragment launcher comprising a casing having a main body for housing an explosive charge, the casing further comprising a first end provided with a launching aperture configured to hold a fragment and a second end provided with a detonation position configured to receive a detonation means for detonating the explosive charge, wherein an inner profile of the casing tapers from the main body towards the launching aperture and from the main body towards the detonation position, such that in use an explosive pressure is directed towards a fragment to be launched.

2. The explosively driven fragment launcher of claim 1, wherein the first end comprises a cap removably attached to the main body,

3. The explosively driven fragment launcher of claim 1, wherein the second end comprises a cap removably attached to the main body.

4. The explosively driven fragment launcher of claim 2, wherein the cap is removably attached to the main body by threaded means.

5. The explosively driven fragment launcher of claim 1, further comprising a spacer with a first and second end, configured to reduce an internal volume of the main body, wherein there is a channel between the first and second end of said spacer.

6. The explosively driven fragment launcher of claim 5, wherein either or both the first and second end of the spacer is or are shaped substantially to match an internal tapering of the main body.

7. The explosively driven fragment launcher of claim 6, wherein the spacer comprises a plastic material.

8. The explosively driven fragment launcher of claim 6, wherein the internal tapering of the main body casing towards the detonation position is between 10 and 70 degrees to a central longitudinal axis of the casing.

9. The explosively driven fragment launcher of claim 8, wherein an internal tapering of the main body casing towards the launching aperture is between 10 and 70 degrees to the central longitudinal axis of the casing.

10. The explosively driven fragment launcher of claim 1, wherein an angle of the internal tapering of the main body casing towards the launching aperture is complementary to that of the internal tapering of the main body casing towards the detonator position.

11. The explosively driven fragment launcher of claim 8, wherein an angle of the internal tapering is 30 degrees to the central longitudinal axis of the casing.

12. The explosively driven fragment launcher of claim 6, wherein an outer casing is cylindrical, the internal tapering of the main body towards the launching aperture and from the main body towards the detonation position is conical.

13. The explosively driven fragment launcher claim 1, comprising an explosive charge within the main body of the casing.

14. An armour test apparatus comprising the fragment launcher of claim 1.

15. A method of explosively launching a fragment at a target comprising the steps of: a. providing an explosively driven fragment launcher according to claim 1; b. providing an explosive charge within the main body of the casing; c. positioning the explosively driven fragment launcher a predetermined distance from the target with the launching aperture aimed at said target; d. inserting a fragment of predetermined size into the launching aperture; e. inserting a detonation means into the detonation position; and f. initiating the detonation means such that an explosive pressure wave is initiated, such that the fragment is explosively launched at the target.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG. 1 illustrates a cross-sectional view of an embodiment of the explosively driven fragment launcher;

[0031] FIG. 2a illustrates cross-sectional view of an alternative embodiment of the explosively driven fragment launcher; and

[0032] FIG. 2b illustrates an exploded view of the embodiment of FIG. 2a.

DETAILED DESCRIPTION

[0033] FIG. 1 shows a cross-sectional view of one embodiment of the explosively driven fragment launcher 100, through the longitudinal axis 120, that which passes symmetrically through the centre of the launcher. The launcher having a cylindrical main body casing 101 machined from mild steel such that three sides of the internal volume are formed. At the first end 102 there is a removably attached cap 103. This cap 103 is machined from the same mild steel as the main body casing 101 and attached using a threaded means (not shown) such that the main body casing 101 and cap 103 have complimentary threads. Furthermore the cap 103 has been machined with an internal conical tapering 104 towards the launch aperture 105 at an angle of 30 degrees to the longitudinal 120. The launch aperture 105, recessed into the end cap 103, is machined to be complimentary to the shape of the fragment (not shown), such that the fragment remains in position through friction fit. The second end 106 shows the internal conical tapering 107 towards the detonation position 108 at an angle of 30 degrees to the longitudinal axis. The detonation position receives the detonation means (not shown). Within the main body casing 101 the explosive charge 109 is shown conformal to the internal tapering 107 of the second end 106. In use the detonation means (not shown) detonates or initiates the explosive charge 109 which in turn generates an explosive shockwave or gases which propagate towards the launch aperture 105 at the first end 102. The internal tapering 104 towards the launch aperture 105 focus the explosive energy onto the fragment (not shown) held in the launch aperture 105, the gases or explosive shockwave then launch the fragment at a target (not shown).

[0034] FIG. 2a shows a cross-sectional view of a second embodiment of the explosively driven fragment launcher 200, through the longitudinal axis, that which passes symmetrically through the centre of the launcher. The launcher having a cylindrical main body casing 201 machined from mild steel such that three sides of the internal volume are formed. At the first end 202 there is a removably attached cap 203. This cap 203 is machined from the same mild steel as the main body casing 201 and attached using a threaded means (not shown) such that the main body casing 201 and cap 203 have complimentary threads. Furthermore the cap 203 has been machined with an internal conical tapering 204 towards the launch aperture 205 at an angle of 30 degrees to the longitudinal axis 220. The launch aperture 205, recessed into the end cap 203, is machined to be complimentary to the shape of the fragment (not shown), such that the fragment remains in position through friction fit. The main body casing second end 206 shows the internal conical tapering 207 towards the detonation position 208 at an angle of 30 degrees to the longitudinal axis 220. The detonation position 208 receives the detonation means (not shown). Within the main body casing 201 the spacer 209 is illustrated with a first end 210 with conical tapering at 30 degrees to the longitudinal axis, such as to complement the shape of the spacer second end 211. The figure further shows the spacer second end 211 conformal to the main body casing 201 internal conical tapering 207. The spacer has a channel 212 which runs from the detonation position 208 through to the explosive charge 213. The explosive charge 213 is shown conformal to the internal volume of the main body casing 201 and the spacer first end 210. In use the detonation means (not shown) detonates or initiates the explosive charge 213 which in turn generates an explosive shockwave or gases which propagate towards the launch aperture 205 at the first end 202. The internal conical tapering 204 towards the launch aperture 205 focus the explosive energy onto the fragment (not shown) held in the launch aperture 205, the gases or explosive shockwave then launch the fragment at a target (not shown).

[0035] FIG. 2b shows an exploded view of the fragment launcher 200, with cylindrical main body casing 201 made of mild steel, a first end 202 with removably attached cap 203, also made of mild steel with launch aperture 205, shaped to receive the fragment 214. The fragment 214 has been machined such that in use a cuboid fragment is launched. The figure further illustrates the spacer 209 made of plastic with conical tapering and the explosive charge 213, shaped to complement the shape of the spacer 209.