PROJECTILE AND FUSE WITH FIN

Abstract

A projectile is outfitted with a target finder and is intended to be fired from a launching device and includes one or several fins where the fins, upon being extended, cause the projectile to be urged into a controlled oscillating movement. A fuse is also provided.

Claims

1. Projectile arranged with target finder, intended to be fired from launching device, comprising one or more extensible fins, wherein the fins, upon extension, cause the projectile to be put into a controlled oscillating movement by varying the design of the fins and/or how far the fins extend or at what frequency or interval the fins extend and/or at what speed and/or acceleration the fins extend.

2. Projectile according to claim 1, wherein the projectile is arranged with one fin.

3. Projectile according to claim 2, wherein fins are arranged on the projectile, in the longitudinal direction of the projectile, in the range between a factor of 0.1 of the projectile caliber to a factor 2 of the caliber of the projectile, from the tip of the projectile.

4. Projectile according to claim 1, wherein the radial extent of the fins relative to the surface of the projectile, in the extended position, is in the range between a factor of 0.1 of the caliber of the projectile and a factor 1 of the caliber of the projectile.

5. Projectile according to claim 1, wherein the width of the fins, the extent of the fin around the projectile in the outer radius of the projectile, in the extended position, is in the range between a factor of 0.1 of the circumference of the projectile and a factor of 0.5 of the circumference of the projectile.

6. Projectile according to claim 1, wherein fins are variably adjustable between fully extended position and fully retracted position.

7. Projectile according to claim 1, wherein the projectile is outfitted with two fins.

8. Projectile according to claim 1, wherein fins are provided with an angle ? of between 0.1 degrees and 5 degrees.

9. Fuse intended to be affixed to a projectile intended to be fired from launching device, where the fuse is outfitted with a target finder and encompasses one or several extensible fins, wherein the fins, upon extension, cause the projectile, whereby the fuse is affixed to a projectile, to be put into a controlled oscillating movement by varying the design of the fins and/or how far the fins extend or at what frequency or interval the fins extend and/or at what speed and/or acceleration the fins extend.

10. Fuse according to claim 9, wherein the fuse is arranged with a fin.

11. Fuse according to claim 9, wherein fins are arranged on the fuse, in the longitudinal direction of the fuse, in the range between a factor of 0, 1 of the caliber of the projectile and a factor of 2 of the caliber of the projectile, from the tip of the fuse.

12. Fuse according to claim 9, wherein the radial extent of the fins relative to the surface of the fuse, in the extended position, is in a range between a factor of 0.1 of the caliber of the projectile to a factor 1 of the caliber of the projectile.

13. Fuse according to claim 9, wherein the width of the fins, the extent of the fins around the fuse in the outer radius of the fuse, in the extended position, is in the range between a factor of 0.1 of the circumference of the fuse to a factor of 0.5 of the circumference of the fuse at the position on the fuse where the fins are situated.

14. Fuse according to claim 9, wherein fins are variable adjustable between a fully extended position and a fully retracted position.

15. Fuse according to claim 9, wherein the fuse is provided with two fins.

16. Fuse according to claim 9, wherein the fins are provided with an angle ? of between 0.1 degrees and 5 degrees.

Description

BACKGROUND AND SUMMARY

[0024] The invention will be described below by reference to the figures that are included there:

[0025] FIG. 1 shows a projectile outfitted with a fuse including an extended fin according to one embodiment of the invention.

[0026] FIG. 2 shows a fuse with a fin in extended position according to one embodiment of the invention.

[0027] FIG. 3 shows an fuse with a fin in extended position according to an alternate embodiment of the invention.

[0028] FIG. 4 shows a projectile in the trajectory on its way to a target object when the fins are extended from the projectile according to an embodiment of the invention.

DETAILED DESCRIPTION

[0029] FIG. 1 shows a projectile 1 intended to be launched from a launching device such as a cannon with a fuse 2, where the fuse can be mounted as a separate unit on the projectile or designed as part of projectile 1. In the shown embodiment, projectile 1 is affected by fins 3, which are extended from projectile 1. Fin 3 can also be called panel, brake panel, brake, wing, spoiler or canard. When fin 3 is retracted, projectile 1 is rotationally symmetrical around a center line C shown in the figure, where the center line is provided in the longitudinal direction of the projectile. When fin 3 is extended, projectile 1 is no longer rotationally symmetrical about shown center line C. Fin 3 may be designed in the form of a cylinder with a diameter of 1 mm-10 mm. Fin 3 can also be designed in the form of a rectangular panel with a thickness, the width of the panel being in the same direction as in the longitudinal direction of the projectile, of between 1 mm-4 mm and a width, the width of the panel being in a direction perpendicular to the thickness, of between 2 mm-15 mm or on a factor between 0.1-0.5 of the projectile's circumference where the circumference refers to the circumference of the projectile at the caliber of the projectile, i.e. where the projectile has the highest diameter. Fin 3 can be deposited radially from the surface of the projectile body between 1 mm-15 mm or on a factor between 0.1-1 of the projectile caliber. The longitudinal position of the fin is 20 mm-150 mm or on a factor between 0.1-2 of the caliber of the projectile, measured from the tip on the projectile. The position in the longitudinal direction of the projectile is in relation to the center of gravity of the projectile, in order to cause a momentum force on the projectile when fin 3 is extended. The position can also be between a factor of ?2.5-2.5 times the projectile caliber relative to the center of gravity of the projectile. In the event that more than one fin 3 is desired, an odd number of fins 3 are preferably provided distributed around the projectile body. Preferably, there is a single fin 3 affixed to the projectile.

[0030] FIG. 2 shows fuse 2 with fin 3 extended. Activation and extension of fin 3 can take place by mechanical, electromechanical, chemical or pyrotechnic device. Fuse 2 is provided with a thread 4 to be attached to a grenade body of a projectile 1. The fuse is outfitted with a target finder 5 which can e.g. be an optical target finder.

[0031] FIG. 3 shows fuse 2 with an inclined fin 3 extended. The fin is inclined relative to a line E-E perpendicular to the center line D-D of the fuse/projectile. Line E-E is perpendicular to the center line D-D which passes through the center of the circularly symmetrical fuse. Fin 3 is inclined at an angle ? 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 inclined fin 3 may take place by means of a mechanical, electromechanical, chemical or pyrotechnic device. In the event that more than one fin 3 is used, when the fins 3 are inclined, both an odd number of fins 3 and an even number of fins 3 distributed around the projectile body can be used. Fuse 2 is provided with a thread 4 to be attached to a grenade body of a projectile 1. The fuse is outfitted with a target finder 5 which can e.g. be an optical target finder.

[0032] FIG. 4 shows the firing course 10 for an embodiment of the invention. Projectile 1 travels in projectile trajectory 11 on its way to a target object 16. Position 12 shows projectile 1 on its way to the target object 16 in the target area 18 before a fin has been extended from projectile 1. Once the fin is extended from the projectile, an oscillation of the projectile begins, which is shown in position 14. When projectile 1 oscillates, a target area 18 can be scanned with a target finder arranged in the projectile. When the projectile oscillates in the trajectory at the same time as the projectile rotates, 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 finder, the projectile can be steered towards the target object 16 or the projectile can burst, or in other ways, act against the target object, e.g. by means of forward-acting splinters. The oscillating movement can be adapted based on the target finder and/or the target object and/or the design of the projectile by varying the design of the fin and/or how far the fin extends or at what frequency or interval the fin extends and/or at what speed and/or acceleration the fin extends. By varying the extension of the fin, the size and appearance of the target area can be changed, e.g. if the target finder identifies an object, the target area can be delimited to the surroundings of the identified object.

[0033] Fin 3, 3 is extended from the fuse 2 or from projectile 1 in the trajectory of projectile 1 to affect the trajectory of the projectile. Fin 3, 3 can e.g. be based on the target of and/or the position of projectile 1. The target of projectile 1 can be programmed or otherwise stored in projectile 1 prior to launch, but can also be communicated to projectile 1 during the projectile's trajectory between the launch device and the target by means of communication equipment such as a radio transmitter. The position of projectile 1 is determined on the basis of a navigation system/control system mounted in the projectile that receives the current position from satellite navigation and/or inertial navigation or other navigation system. The control system can continuously evaluate the current position relative to the target position and the calculated speed to control and/or optimize the projectile's trajectory.

[0034] The target of projectile 1 can also be determined by means of a target finder 5 included in projectile 1, which identifies a target and possibly steers projectile 1 towards that target. Control of projectile 1 can e.g. take place by means of the braking ability, which entails longitudinal steering, and also include lateral steering with intended controls. The target of projectile 1 can also be combated by the projectile in the projectile's trajectory, e.g. by means of forward-acting splinters.

[0035] At a suitable position determined from the control system, a lock is initiated which keeps the fin in the retracted position, which releases fin 3, 3 or fins 3, 3. Fin 3, 3 or fins 3, 3 are extended by means of the rotational force of the projectile and/or by means of a spring mounted in the extension mechanism or another elastically deformed and prestressed actuating device or by means of an actuator such as an electric motor.

[0036] Upon extension of fin 3, 3 or fins 3, 3, projectile 1 will commence a predetermined oscillating movement, based on the extension, design, size, and location of fin 3, 3. Extension of the fin will also affect the rotation of the projectile in the event that the projectile is rotationally stabilized and thus rotating.

[0037] The projectile 1 is designed with an odd number of fins 3, 3, e.g. one, three, five or seven fins 3, 3 or with an even number of fins 3, 3 for example two, four, six or eight fins 3, 3. The fin or fins 3, 3 extend radially from the projectile. The extension mechanism in one embodiment can only extend the fin or fins 3, 3. Other mechanisms, not shown in the figure, can extend the fin completely or partially and retract the fin completely or partially.

[0038] An alternative embodiment, not shown in the figure, of the extension mechanism means that both the extension and retraction of fins 3, 3 can be regulated on the basis of both speed and level or length. Extension and retraction are performed by means of a control system mounted in the projectile for the creation of variable oscillation effect on the projectile 1 by the fins 3, 3 being extended completely, partially or alternately in and out of the projectile 1. By controlling the extension mechanism, the oscillation effect can be adjusted variably to variably control the oscillation of the projectile 1.

[0039] The invention is not limited to embodiments specifically shown, but can be varied in different ways within the framework of the claims.

[0040] For instance, it is clear that the number, size, material and shape of the elements and details outfitted with a fin are to be adapted according to the type(s) of projectile(s) and weapon systems and/or other construction-related properties, which are applicable to each individual case.

[0041] It is clear that the projectile embodiments described above with a fin may include several different dimensions and projectile types depending on the area of use and barrel width. However, the above refers to at least the most common types of grenades today of between about 20 mm-203 mm.