EP4341636A1

EP4341636A1 - Projectile and fuse with brake

Info

Publication number: EP4341636A1
Application number: EP22805071.2A
Authority: EP
Inventors: Thomas Pettersson; Björn Johansson
Original assignee: BAE Systems Bofors AB
Current assignee: BAE Systems Bofors AB
Priority date: 2021-05-19
Filing date: 2022-05-04
Publication date: 2024-03-27
Also published as: SE2100080A1; WO2022245265A1; US20240200917A1

Abstract

The invention concerns a projectile (1) outfitted with a target finder (5), intended to be fired from a launching device, comprising one or several brake flaps (3, 3´) where the brake flaps (3, 3´), after their being extended, cause the projectile (1) to be arranged in a controlled oscillating movement. The invention also concerns a fuse.

Description

PROJECTILE AND FUSE WITH BRAKE

TECHNICAL FIELD

[0001 ] The present invention concerns a projectile outfitted with a brake, where the projectile aims to be fired from a launching device. The projectile includes one or several extendable brake panels which affect the properties of the projectile in the trajectory of the projectile. Additionally, the invention is comprised of a fuse intended for a projectile, whereby said fuse includes one or several brake panels which are arranged so as to affect the projectile upon their being extended.

BACKGROUND OF THE INVENTION, PROBLEM AREA AND STATE OF THE ART

[0002] Barrel-launched projectiles, e.g. Artillery projectiles, are fired against target objects. The projectiles are intended to act against a target object and can, for example, steer towards the target object, with for example final phase control, or act against the target object by bursting at an appropriate time, or in other ways causing effect against the target object, for example by splinters acting on the target object. Final phase control, i.e. the control at the end of the projectile's trajectory near the target, can e.g. take the form of the projectile being outfitted with a target finder that scans the target area for target objects and steers the projectile towards an identified target object, and can thus act by means of striking the target object or by means of splintering effect by bursting in the vicinity of the target object. Alternatively, the projectile can act by means of forward-directed splintering when the target detector has detected a target object and initiates effect against the target object, for example by bursting at the right time and thus causing splintering effect against the target object, for example by forward-directed splintering effect. [0003] Patent document US 5,155,294 shows a warhead outfitted with wings so as to influence the fall movement of the submunition towards the ground. The patent document does not show a projectile or a fuse outfitted with brake flaps.

[0004] Additional problems which the present invention seeks to solve will become apparent in connection with the following detailed description of the various embodiments.

PURPOSE AND FEATURES OF THE INVENTION

[0005] By extending brake flaps during a projectile's movement towards a target object or target area, a movement oscillating on the projectile can be achieved. The oscillation can e.g. be in the order of 10 - 20 degrees. The oscillation means that a conical area can be scanned with a sensor affixed to the projectile.

[0006] The invention consists of a projectile outfitted with a target finder, intended to be fired from a launching device, comprising one or several brake flaps where the brake flaps, after their being extended, cause the projectile to be arranged in a controlled oscillating movement.

[0007] According to further aspects of the projectile according to the invention, the following applies: the projectile is outfitted with an effect part where the choice of effect can take place with respect to; i.) directional explosive effect in the forward direction of the projectile, or ii.) shattering effect in the radial direction of the projectile that the brake flaps are affixed to the projectile, in the longitudinal direction of the projectile, in a range between a factor of 0.1 of the projectile caliber to a factor 2 of the projectile caliber, from the tip of the projectile. that the radial extent of the brake flaps relative to the surface of the projectile, in the extended position, is in the range between a factor of 0.1 of the projectile caliber to a factor of 1 of the projectile caliber. that the width of the brake flaps, the extent of the brake flap around the projectile in the outer radius of the projectile, in the extended position, is in an interval between 0.1 of the circumference of the projectile to a factor of 0.5 of the circumference of the projectile. that the adjustment of the brake flaps can be varied between a fully extended position and a fully retracted position.

[0008] That the brake flaps are arranged with an angle a of between -45 degrees and 45 degrees.

[0009] In addition, the invention consists of a fuse, to be affixed to a projectile, and intended to be fired from a launching device, where the fuse is outfitted with a target finder and comprises one or several brake panels, characterized in that the brake panels, after being extended, cause the projectile, where the fuse is mounted on a projectile, to end up in a controlled oscillating movement.

[0010] According to further aspects of the fuse according to the invention, the following applies: that the brake panels are affixed to the fuse, in the longitudinal direction of the fuse, in a range between a factor of 0.1 of the projectile caliber to a factor 2 of the projectile caliber, from the tip of the fuse. that the radial extent of the brake panels relative to the surface of the fuse, in the extended position, is in the range between a factor of 0.1 of the projectile caliber to a factor of 1 of the projectile caliber. that the width of the brake panels, the extent of the brake panel around the fuse in the outer radius of the fuse, in the extended position, is in an interval between 0.1 of the circumference of the fuse to a factor of 0.5 of the circumference of the fuse. that the adjustment of the brake panels can be varied between a fully extended position and a fully retracted position.

[0011] That the brake panels are arranged with an angle a of between 0.1 degrees and 10 degrees.

THE ADVANTAGES AND EFFECTS OF THE INVENTION

[0012] The invention demonstrates a simple method for causing an oscillation on a projectile by means of brake flaps, which result in a conical area being possible to scan with a target finder arranged in the projectile. When a target is observed by the target seeker in the scanned target area, the projectile can act against the target. The target seeker scans the target area for target objects and can act against the target object with forward-directed explosive effect, e.g. with beam-forming or splinter-forming RSV (Directed Explosive Effect)

LIST OF FIGURES

[0013] The invention will be described below by reference to the figures that are included there:

Fig. 1 shows a projectile outfitted with a fuse including extended brake flaps according to one embodiment of the invention.

Fig. 2 shows a fuse with brake flaps in extended position according to an embodiment of the invention.

Fig. 3 shows a fuse in an alternative view according to an embodiment of the invention.

Fig. 4 shows a projectile outfitted with an effect part with directed explosive effect according to one embodiment of the invention.

Fig. 5 shows a projectile in the trajectory on its way towards a target object when the brake flap is extended from the projectile according to an embodiment of the invention. DETAILED DESCRIPTION OF EMBODIMENT

[0014] Fig. 1 shows a projectile 1 , intended for launching in a launching device such as a cannon, with fuse 2, where the fuse can be mounted as a separate unit on the projectile or designed as part of the projectile 1 . The projectile 1 is affected in the shown embodiment of brake flaps 3, 3^' which are extended from the projectile 1 . The brake flaps 3, 3^' can also be called panel, panel, fin, brake, wing, spoiler or canard. When the brake flaps 3, 3^' are retracted, the projectile 1 is rotationally symmetrical about a center line C shown in the figure, where the center line is arranged in the longitudinal direction of the projectile. When the brake flaps 3, 3^' are extended, the projectile 1 is no longer rotationally symmetrical about shown center line C. The brake flaps 3, 3^' can be designed in the form of a rectangular panel with thickness, the panel extending in the same direction as the projectile’s longitudinal direction, of between 1 mm - 4 mm and a width, the width of the panel regarding a direction perpendicular to the thickness, of between 2 mm - 15 mm or of a factor between 0.1 - 0.5 of the projectile's circumference, where the circumference refers to the projectile's circumference at the projectile caliber, i.e. where the diameter of the projectile is at its largest. The brake flaps 3, 3^' can be extended radially from the source of the body of the projectile by between 1 mm - 15 mm or of a factor between 0,1 - 1 of the caliber of the projectile. The placement of the brake flags in a longitudinal direction is, counting from the tip of the projectile, 20 mm - 150 mm, or of a factor between 0.1 - 2 of the caliber of the projectile. The positioning in the longitudinal direction of the projectile is done in relation to the center of gravity of the projectile in order to cause a moment on the projectile when the brake flaps 3, 3^' are extended. The positioning can also be between a factor of -2.5 - 2.5 times the caliber of the project relative to the projectile's center of gravity. Preferably, two brake flaps 3, 3^' are arranged on the projectile. [0015] Fig. 2 shows fuses 2 with brake flaps 3, 3^' extended. The activation and extending of the brake flaps 3, 3^' can take place by mechanical, electromechanical, chemical or pyrotechnic device. The fuse 2 is arranged with a thread 4 to be affixed to a grenade body to for a projectile 1 (not shown in figure 2). The fuse is outfitted with a target finder 5 which can e.g. Be an optical target finder.

[0016] Fig. 3 shows fuse 2 from the side in an alternative embodiment with inclined brake panels 3, 3^' where only one fin is visible in the projection shown. The brake panels are inclined relative to a line E-E perpendicular to the center line D-D of the fuse /projectile. The line E-E is perpendicular to the center line D-D which passes through the center of the circularly symmetrical fuse. The brake panels 3, 3^' are inclined at an angle a relative to the line E-E. The angle is preferably in the range of 0.1 degrees to 5 degrees. The activation and extension of the inclined fins 3, 3^' can take place by mechanical, electromechanical, chemical or pyrotechnic device. The fuse 2 is outfitted with a thread 4 to be affixed to a grenade body of a projectile 1 , not shown in figure. The fuse is outfitted with a target finder 5 which can be, for example, an optical target finder. The spark plug is arranged with a chamfer 7 which is used to mount the spark plug to the projectile.

[0017] Fig. 4 shows projectile 1 arranged with an effect part outfitted with an effect part for directed explosive effect 6, RSV. RSV is available in two common forms, RSV III - beamforming, and RSV IV - projectile forming. Radiation forming RSV usually uses a cone-shaped metal insert, often copper or aluminum, as well as an explosive charge arranged for the cone. When the explosive detonates, the metal cone is reshaped and pushed away. A subset of the metal forms a narrow beam at a very high speed, can be in the order of 8 km/s to 10 km/s, which acts with great force against the target, e.g. by penetrating an armor plate. The remaining part of the metal forms a subsequent projectile (also called "slug") which moves much slower, about 500 m/s. Effect parts with beam-forming RSV charges can penetrate armor with a thickness in the order of 5-7 times the diameter of the effect part/charge itself. A projectile-forming RSV uses a metal insert that is bowl-shaped or has a much flatter cone than a beam-forming RSV. During detonation, the entire metal insert forms a continuous projectile that moves at a speed of approximately 1 .5 km/s - 2 km/s. The projectile's ability to penetrate armor is significantly worse than that of a beam -forming RSV, but it retains the impact force over much longer distances, often up to hundreds of meters. The effect of the projectile on a projectile-forming RSV after penetration of the armor or protective cover is also significantly better relative to the effect of the projectile forming subsequent projectile ("slug") of a beam-forming RSV.

[0018] Fig. 5 shows a firing course 10 for an embodiment of the invention. The projectile 1 travels in a projectile trajectory on its way to a target object 16 in the target area 18. Once the brake panel is extended from the projectile, the projectile begins to oscillate. When projectile 1 oscillates, a target area 18 can be scanned with a target finder affixed to the projectile. When the projectile oscillates, the scanned target area 18 will be mainly circular and the target finder will be able to search the entire target area 18. When a target object 16 has been detected by the target seeker, the projectile can act against the target object 16 by means of an explosive charge in the projectile exploding and bursting with splinters or a beam acting against the target object, or in other ways, acting against the target object. When a target object has been detected by the target seeker, the effect preferably takes place with a forward-directed effect with a directed explosive effect, RSV. In the event that no target is identified, the action part can act radially from the projectile, for example by splitting action.

[0019] The oscillating movement can be adapted based on the target finder and/or target object and/or projectile design by varying the design of the brake panel and/or how far the brake panel extends or at what frequency or interval the brake panel extends and/or at what speed and/or acceleration the brake panel extends. By varying the brake panel extension, the size and appearance of the target area can be changed. For instance, if the target finder identifies an object, the target area can be delimited so as to encompass only the surroundings of the identified object.

[0020] The brake panels 3, 3^' extend from the spark plug 2 or from the projectile 1 in the trajectory of projectile 1 , so as to influence the projectile's attitude or angle relative to the projectile's trajectory. Examples of control of the brake panel 3, 3^' can be based on the target of projectile 1 and/or on the position of projectile 1. The target of projectile 1 can be programmed or otherwise stored in projectile 1 before launch, but can also be communicated, by means of communication equipment such as a radio transmitter, to projectile 1 in the projectile's path between the launch device and the target. The position of projectile 1 is determined on the basis of a navigation/control system mounted in the projectile, which receives the current position from satellite navigation and/or inertial navigation or another navigation system. The control system can continuously evaluate the current position relative to the target position and the calculated speed, so as to control and/or optimize the projectile's trajectory.

[0021] The target of projectile 1 can also be determined with a target finder 5 included in the projectile 1 , which identifies a target and possibly steers projectile 1 towards that target. Control of projectile 1 can e.g. be performed by means of the braking ability, which entails longitudinal steering, and also includes lateral steering by means of actuators intended for this purpose. The target of projectile 1 can also be combated by the projectile in the projectile's trajectory, e.g. B means of forward-acting splinters and/or a beam.

[0022] At a suitable position, as determined by the control system, a lock, which retains the brake panels in the extended position, is initiated, thus causing the brake panels 3, 3^' to be released. The brake panels 3, 3^' are extended by the rotational force of the projectile and/or preferably by a spring mounted in the extension mechanism or a different elastically deformed and prestressed actuating device or by means of an actuator such as an electric motor.

[0023] Once the brake panels 3, 3^' are extended, projectile 1 commences an oscillating movement, based on the extension, design, size, location and oscillation movement of the brake panels 3, 3^'. Extension of the brake panels will also affect the rotation of the projectile in cases where the projectile is rotating.

[0024] An alternative embodiment, not shown in the figure, of the extension mechanism means that both the extension and retraction of the brake panels 3, 3^' can be regulated on the basis of both speed and level or length. Control of extension and retraction takes place by means of a control system mounted in the projectile for the generation of a variable oscillation effect on the projectile 1 by means of the brake panels 3, 3^' being extended, either completely, partially or alternately, in and out of the projectile 1. By controlling the extensions, the oscillation effect can be adjusted variably to variably control the oscillation of the projectile.

ALTERNATIVE DESIGN TYPES

[0025] The invention is not limited to the types of design specifically shown, but can be varied in different ways within the framework of the claims.

[0026] For instance, it is clear that the number, size, material and shape of the elements and details included in the brake panel-outfitted projectile, are adapted to the projectile type(s), weapons system(s) and/or other construction- related properties, which are applicable to each individual case.

[0027] It is clear that the the above-described projectile embodiments which include brake panels may include several different dimensions and projectile types depending on the area of use and the barrel width. The above, however, refers to at least the most common types of grenades today of between approximately 20 mm - 203 mm.

Claims

1 . A projectile (1 ) outfitted with a target finder (5), intended to be fired from a launching device, comprising one or several extendable brake panels (3), characterized in that the brake panels (3, 3^'), upon being extended, cause the projectile (1 ) to be arranged in a controlled oscillating movement by means of the brake panels (3, 3^') being completely, partially or alternately extended, in and out of the projectile (1 ).

2. The projectile (1 ) of claim 1 , characterized in that the projectile is outfitted with an effect part, where the choice of effect can concern; i.) directed explosive effect in the forward direction of the projectile, or ii.) splinter effect in the radial direction of the projectile.

3. The projectile (1 ) of the preceding claims, characterized in that the brake flaps (3, 3^') are affixed to the projectile (1), in the longitudinal direction of the projectile, in a range between a factor of 0.1 of the caliber of the projectile (1 ) to a factor 2 of the caliber of the projectile (1 ), from the tip of the projectile (1 ).

4. The projectile (1 ) of the preceding claims, characterized in that the radial extent of the brake panels (3, 3^') relative to the surface of the projectile (1 ), in the extended position, is in the range between a factor of 0.1 of the caliber of the projectile (1 ) to a factor of 1 of the caliber of the projectile (1 ).

5. The projectile (1 ) of the preceding claims, characterized in that the width of the brake panels (3, 3^'), the extent of the brake flap around the projectile (1) in the outer radius of the projectile, in the extended position, is in an interval between 0.1 of the circumference of the projectile (1 ) to a factor of 0.5 of the circumference of the projectile (1 ).

6. The projectile (1 ) of the preceding claims, characterized in that the the position of the brake panels (3, 3^') can be varied between a fully extended position and a fully retracted position.

7. The projectile (1 ) of the preceding claims, characterized in that the the (3, 3^') are arranged with an angle a of between -45 degrees and 45 degrees.

8. A fuse (2), to be affixed to a projectile (1 ), and intended to be fired from a launching device, where the fuse (2) is outfitted with a target finder (5) and comprises one or several brake panels (3, 3^'), characterized in that the brake panels (3, 3^'), after being extended, cause the projectile (1 ), where the fuse is mounted on a projectile (1 ), to end up in a controlled oscillating movement.

9. The fuse (2), to be affixed to a projectile (1 ) of claim 8, characterized in that the brake flaps (3, 3^') are affixed to the fuse (2), in the longitudinal direction of the fuse, in a range between a factor of 0.1 of the caliber of the projectile (1 ) to a factor 2 of the caliber of the projectile (1 ), from the tip of the fuse (2).

10. The fuse (2), to be affixed to a projectile (1) of any of claims 8-9, characterized in that the radial extent of the brake panels (3, 3^') relative to the surface of the fuse (2), in the extended position, is in the range between a factor of 0.1 of the caliber of the projectile (1 ) to a factor of 1 of the caliber of the projectile (1 ).

11. The fuse (2), to be affixed to a projectile (1) of any of claims 8-10, characterized in that the width of the brake panels (3, 3^'), the extent of the brake panel around the fuse (2) in the outer radius of the fuse (2), in the extended position, is in an interval between 0.1 of the circumference of the fuse (2) to a factor of 0.5 of the circumference of the fuse (2) at the position on the fuse where the brake panels (3, 3^') are arranged.

12. The fuse (2), to be affixed on a projectile (1) of any of claims 8-11, characterized in that the the position of the brake panels (3, 3^') can be varied between a fully extended position and a fully retracted position.

13. The fuse (2), to be affixed on a projectile (1) of any of claims 8-12, characterized in that the the (3, 3^') are arranged with an angle a of between 0.1 degrees and 10 degrees.