WO2022177490A1

WO2022177490A1 - Warhead arranged with parachute, method for regulating the attachment of a warhead to a parachute and a projectile

Info

Publication number: WO2022177490A1
Application number: PCT/SE2022/050140
Authority: WO
Inventors: Thomas Pettersson; Lars-Åke CARLQVIST
Original assignee: Bae Systems Bofors Ab
Priority date: 2021-02-19
Filing date: 2022-02-09
Publication date: 2022-08-25

Abstract

The invention relates to a method for regulating the attachment of a parachute to a warhead where the parachute is attached to the warhead by at least one attachment point arranged on a first rotatable circular disc so that the attachment point is moved when the first rotatable circular disc is rotated. and thus affects the position and/or direction of the warhead relative to the parachute. The invention further relates to a warhead, as well as to a projectile provided with the warhead.

Description

WARHEAD ARRANGED WITH PARACHUTE, METHOD FOR REGULATING THE ATTACHMENT OF A WARHEAD TO A PARACHUTE AND A PROJECTILE

TECHNICAL FIELD [0001] The present invention relates to a warhead provided with a parachute, as well as to a method for regulating the attachment of a parachute to a warhead. As well as a projectile provided with a warhead.

BACKGROUND OF THE INVENTION, PROBLEM AREA AND KNOWN TECHNOLOGY

[0002] Warheads, such as submunitions, which are folded or otherwise separated from a carrier, may be provided with a parachute for purposes of reducing the rate of descent of the warhead. In one example, the warhead is arranged in a carrier grenade which is fired from a launching device, such as an artillery piece, and at a certain time or position in the path of the carrier grenade, the warhead is released from the carrier grenade and descends towards the ground. When the warhead descends towards the ground, and the target objects which are arranged on the ground, the warhead may be provided with sensors which scan the ground. The scanning area of the sensors can be controlled by influencing the position of the warhead.

[0003] Patent document US 4,050,381 describes a warhead provided in a parachute for purposes of being able to act on ground targets. By arranging the attachment to the parachute so that it makes use of different length cords which attach to the parachute, the warhead can be made to angle towards the vertical axis in a specified position in order to make it possible for a given area to be scanned. When a target object is detected, the warhead can, through a directed explosive action, act on the target. The patent document does not show that the angle of the warhead relative to the vertical axis can change during the descent of the warhead towards the ground. [0004] A solution to the problem above and additional problems along with solutions are described below.

THE INVENTION AND ITS PURPOSE

[0005] One purpose of the present invention is to solve the problems identified above.

[0006] An additional purpose of the present invention is to provide a method for regulating the attachment of a parachute to a warhead where the parachute is attached to the warhead by at least one attachment point arranged on a first rotatable circular disc so that the attachment point is moved when the first rotatable circular disc is rotated and thus affects the position and/or direction of the warhead relative to the parachute.

[0007] According to additional aspects of a method for regulating the attachment of a parachute to a warhead, the following applies; the first rotatable circular disc is arranged on a second rotatable circular disc the rotation of the first rotatable circular disc and the rotation of the second rotatable circular disc make the warhead capable of moving relative to the parachute, which allows a ground surface to be scanned by a homing device provided within the warhead.

[0008] The invention further relates to a warhead provided with a parachute where the parachute is attached by means of at least one cord in at least one attachment point on the warhead and where the attachment point is arranged on a first rotatable circular disc, with said rotatable circular disc being arranged on the upper side of the warhead. [0009] According to additional aspects for a warhead provided with a parachute applies, the following applies; the first rotatable circular disc is arranged inside a second rotatable circular disc. the diameter of the first rotatable circular disc lies within the range of 40%- 60% of the diameter of the warhead. the diameter of the first rotatable circular disc lies within the range of 80%- 100% of the diameter of the warhead. the warhead is provided with a homing device.

[0010] The invention is further compromised of a projectile, said projectile being provided with a warhead, where said warhead is arranged to be separated from the projectile along the trajectory of the projectile.

LIST OF FIGURES

[0011] The invention will be described below by reference to the figures that are included there:

[0012] Fig. 1 shows a projectile with a warhead and a parachute viewed from the side according to one embodiment of the invention.

[0013] Fig. 2 shows a warhead viewed from the side according to one embodiment of the invention.

[0014] Fig. 3a shows a warhead viewed from above in a first position according to one embodiment of the invention. [0015] Fig. 3b shows a warhead viewed from above in a second position according to one embodiment of the invention.

[0016] Fig. 3c shows a warhead viewed from above in a third position according to one embodiment of the invention.

[0017] Fig. 4a shows a warhead in a parachute in a first position viewed from the side according to one embodiment of the invention.

[0018] Fig. 4b shows a warhead in a parachute in a second position viewed from the side according to one embodiment of the invention.

[0019] Fig. 5 shows a warhead in a parachute in the process of descending towards the ground viewed from the side according to one embodiment of the invention.

DETAILED DESCRIPTION OF EMBODIMENT

[0020] An ejection device, also termed a cannon, a howitzer or a piece, in the sense of an artillery piece, has the goal of making use a propellant for the purpose of firing, or ejecting, a projectile. Preferably, a propellant, such as gunpowder, is initiated in one part of the cannon, oftentimes a chamber specifically adapted to the purpose. Initiation takes place by way of igniting the fuze, for instance by means of an ignition cartridge or an igniter in an ammunitions device, which is initiated by means of striking. Other methods for igniting the propellant may include ignition of the propellant by means of laser energy or electric energy. The propellant burns at a high rate and results in large amounts of gas being produced, which creates a gas pressure in the chamber which propels the projectile out of the barrel of the firing ejection device. The propellant has been adapted in order to generate a constant pressure on the projectile during the entire barrel procedure, to the greatest extent possible, as the projectile movies in the barrel, which results in the projectile leaving the mouth of the barrel with high speed.

[0021 ] Projectiles, such as various types of grenades, generally include some form of warhead. The warhead preferably comprises some form of explosive substance. If the warhead is intended to act upon ground targets, new forms of directed explosive effect, also called RSV, should be used. The warhead is in an embodiment where it is provided with a parachute in order to affect the descent rate of the warhead, but the parachute may also be used in order to affect the attitude, direction or position in the trajectory towards the ground.

[0022] Projectiles intended for artillery use generally comprise a warhead, which may take the form of a grenade, or the warhead may be arranged that allows is to be separated from the projectile, in which case it is referred to as a carrier grenade. The projectile is furthermore provided with a fuze which is disposed on the grenade prior to the projectile being arranged, loaded, into the artillery cannon. The reasons that the fuze is not arranged along with the grenade prior to being employed. The fuze is generally arranged with threads and is screwed on to the grenade/body of the projectile. The fuze can also be programmed, such as by means of modifying the fuze mechanically, for instance by turning part of the fuze to a certain desired position. Alternatively, the fuze can be programmed electronically, such as by bringing it in contact with the fuze or by means of inductive/capacitive programming.

[0023] In cases where the projectile travels towards a target object, a warhead may be separated from the projectile for purposes of combating target objects on the ground, the projectile is a carrier grenade for a warhead intended to descend towards the ground along the trajectory of the projectile. Preferably this is done in order to combat various types of combat vehicles, but other target objects may also be combated. The warhead is preferably provided with a parachute which limits the rate of descent of the warhead. Furthermore, the warhead can be disposed so as to have either no rotation or reduced rotation once the warhead leaves the projectile, for example by the warhead being arranged in a canister which slows down the rotation after the canister has left the projectile. In most cases, the warhead will have a high rotation speed, as the projectile is rotation-stabilized, i.e. the projectile is made to rotate as it is fired by means of a groove in the barrel which causes the projectile to rotate. The projectile, along with the warhead, can also be fired from a smooth-bore barrel, in which cases the projectile will have no rotation. When the warhead is disposed in the parachute and descends towards the ground, a sensor, such as a homing device, can scan the ground surface for suitable target objects. The homing device is arranged on the warhead, and by changing the direction/position of the warhead relative to the parachute, the direction/position of the sensor/homing device, and thus the surface or area on the ground over which the sensor/homing device performs the scan, can be altered. When a target object has been identified by the sensor/homing device, the warhead can be prepared so that it can act on the target object. For example, the warhead can be directed towards the target object, by the directing/positioning of the warhead relative to the parachute, so that, at a certain height from the target object, the warhead can act on the target object, for example by initiating a directed explosive action and combating the target object with an RSV beam and/or projectile-forming RSV.

DESCRIPTION OF FUNCTIONS

[0024] Fig. 1 shows a projectile 100, provided with a warhead 1 and a parachute 10. The projectile 100 is disposed so as to release the warhead 1 with the parachute 10 at a certain time or position. For example, the projectile 100 can be programmed prior to launch in order to cause a separation of the warhead 1 at a certain time after launch or at a certain position in the trajectory. The projectile 100 may be provided with a device, such as a fuze 101 , that allows its position to be determined, such as a GPS receiver. Furthermore, the projectile 100 may be provided with fins or some other control device for purposes of moving the projectile 100 to a certain position. Furthermore, the projectile 100 may be provided with a homing device or some other device for purposes of recording information. At a certain position, the target seeker can identify target objects on the ground, such as combat vehicles, and, when the target objects have been identified, the warhead 1 can be separated from the projectile 100. In the shown embodiment, the projectile 100 is provided with a single warhead, but it may be provided with two or more warheads in other embodiments. Furthermore, the warhead and the parachute can be arranged in a container, such as a canister, which holds the warhead 1 and the parachute 10 together when they are separated from the projectile 100. When the canister with the warhead 1 and the parachute 10 is separated from the projectile, the warhead 1 and the parachute 10 can be separated from the canister, for example after the canister has potentially slowed down the rotation and potentially also the fall speed. When the active part has left the canister, the parachute is unfolded and the combat phase against ground targets can be initiated by means of a homing device in the warhead commencing its search for ground targets.

[0025] Fig. 2 shows a warhead, preferably with a substantially cylindrical shape, with an upper side 2 and a lower side 4. The lower side 4 may have a smooth design but may also be comprised of a RSV cone 6, which entails a concave design. The lower side 4 may also be comprised of a concave RSV cone 6 with a cover plate arranged in front of the RSV cone 6. Within the central unity 7 of the warhead, energetic material, such as an explosive, and homing devices/sensors, if any, may be provided, for instance in order to be unfolded radially from the central unity 7 of the warhead. Furthermore, any sensors can be arranged on the lower side 4 of the warhead, and sensors may also be arranged so that they are folded out from the warhead, by means of an approach not further described in this application. The upper side 2 of the warhead 1 is arranged with a first rotatable circular disc 3 and, in an alternative embodiment, the first rotatable circular disc 3 is arranged within an additional rotatable circular disc, a second rotatable circular disc 5. An attachment point 3 is disposed on the rotatable circular disc 9, on which the cords for a parachute, not shown in fig 2, are attached. The rotatable circular discs 3, 5, may for instance be attached to an actuator, such as an engine, which can rotate the discs 3, 5. The rotation of disc 3 or 5 affects the position of attachment point 9. Furthermore, the first rotatable circular disc 3 and the second rotatable circular disc 5 can be disposed on at least one actuator, such as a motor, which, by means of gears or other mechanical propulsion, affects the position of the first rotatable circular disc 3 and the second rotatable circular disc 5 simultaneously. In one embodiment, a first motor is disposed on the first rotatable circular disc 3 and a second motor is disposed on the second rotatable circular disc 5. The first rotatable circular disc 3 is preferably arranged on and/or within the second rotatable circular disc 5, which means that, when the second rotatable circular disc 5 is rotated, the first rotatable circular disc 3 is also moved. On the other hand, the first rotatable circular disc 3, in one embodiment, can be rotated without the second rotatable circular disc 5 being rotated or moved.

[0026] For instance, a loop can be provided in the attachment point, onto which a parachute May be attached. Furthermore, the attachment point may be provided with a bearing, such as a ball bearing, which means that the warhead is able to rotate relative to the parachute.

[0027] Fig. 3a shows the upper side of a warhead 1 where the first rotatable circular disc 3 and the second rotatable circular disc 5 are shown in a first position. In this first position, the attachment point 9 is disposed so that the attachment point is located at or near the center of the warhead 1 . In this first position, the warhead will be disposed inside, or near, a completely vertical position relative to the ground surface.

[0028] Fig. 3b shows the upper side of a warhead 1 where the first rotatable circular disc 3 and the second rotatable circular disc 5 are shown in a second position. In this second position, the attachment point 9 is disposed so that the attachment point is located within the center of the warhead and the outer radius of the warhead. In this second position, the warhead 1 will be disposed so that the warhead is angled somewhat relative to the ground surface, which causes the warhead to be skewed in a manner which allows for the homing device to scan an area which is not located right underneath the warhead.

[0029] Fig. 3c shows the upper side of a warhead 1 where the first rotatable circular disc 3 and the second rotatable circular disc 5 are shown in a third position. In this third position, the attachment point 9 is arranged so that the attachment point is located near the outer radius of the warhead 1 . In this third position, the warhead 1 will be disposed so that the warhead is yet more angled relative to the ground surface, which causes the warhead to be skewed in a manner which allows for the homing device to scan an even larger area relative to the second position.

[0030] In one application, the first rotatable circular disc 3 is rotated so that the attachment point 9 approaches the outer radius of the warhead 1. The warhead 1 will be skewed in this position, which means that the lower side 4 of the warhead will be inclined against the vertical axis. The warhead can then, by means of rotating the second circular disc 5, be rotated in a skewed position, which enables a surface on the ground to be scanned. By varying the first circular disc 3 and/or the second circular disc 5, a ground surface is able to be scanned by the homing device which is arranged in the warhead 1.

[0031] Fig. 4a shows a warhead 1 provided attached to a parachute 10 by at least one rope in a first position when the attachment point 9 disposed in, or near, the center of the warhead 1 . The warhead is located in such a position that the warhead is, or is close to being, circularly symmetric around an imaginary vertical line.

[0032] Fig. 4b shows a warhead 1 provided attached to a parachute 10 by at least one rope in a second position when the attachment point 9 disposed near the outer radius of the warhead 1. The warhead 1 is in the second position, angled from an imaginary vertical line. The angle of the warhead 1 relative to the imaginary vertical line may be varied by varying the first circular disc 3 and the second circular disc 5.

[0033] Fig. 5 shows the warhead 1 on its way to the ground when the warhead is inclined relative to the vertical line, i.e. the attachment point 9 is arranged adjacent the outer radius of the warhead 1. A sensor and/or homing device arranged in the warhead 1 is able to scan the ground area. In Fig. 5, the scan vector 22 of the sensor is visualized. The sensor and/or homing device may for instance be an imaging sensor, an electromagnetic sensor such as an optical sensor in the visible region or the IR region, or a different electromagnetic sensor or a different sensor. By varying, or rotating, the first circular disc 3 and the second circular disc 5, a ground surface can be scanned by the homing device/sensor, in figure 5 shown as target area 20. When a target object is identified by the sensor, for example by relying on the shape, signature, thermal signature or other parameter of the target object, the warhead is able to prepare the action against the target object. For example, the warhead may be arranged so that the lower side 4 of the warhead is aimed towards the target object. At a certain height or position, the warhead initiates an action against the target object. In a first embodiment, directed explosive action (RSV), preferably projectile-forming RSV, is used when acting on the target object.

EXAMPLES OF EMBODIMENTS

[0034] Examples of carrier grenades include projectiles of caliber 80-155 mm provided with fuzes that allow them to separate a warhead, such as a submunition, from the projectile at a given time or position. The length of the projectile, excluding the fuze, is preferably between 100-950 mm. The warhead is provided with a homing device, such as an imaging sensor, and a warhead device with RSV.

ALTERNATIVE DESIGN TYPES [0035] 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.

[0036] For instance, it is clear that the number, size, material and shape of the elements and details included in the warhead are to be adapted according to the projectile(s) and projectile compositions, along with other construction- related properties, which are applicable to each individual case.

[0037] For instance, the warhead can be arranged so that it is capable of exploding, emitting shrapnel, catching fire, exerting a thermobaric effect, fighting fires, and so that it can be used as a training projectile, in light kits, in smoke kits, in order to exert electromagnetic effect, for purposes of bringing about electromagnetic disturbances or for other loads and functions.

Claims

1. Method for regulating the attachment of a parachute to a warhead, characterized in that the parachute is attached to the warhead by at least one attachment point arranged on a first rotatable circular disc so that the attachment point is moved when the first rotatable circular disc is rotated and thus affects the position and/or direction of the warhead relative to the parachute.

2. Method for regulating the attachment of a parachute to a warhead according to claim 1 , characterized in that the first rotatable circular disc is arranged on a second rotatable circular disc.

3. Method for regulating the attachment of a parachute to a warhead according to claim 2, characterized in that the rotation of the second rotatable circular disc makes the warhead capable of moving relative to the parachute, which allows a ground surface to be scanned by a homing device provided within the warhead.

4. Warhead (1) arranged with a parachute (10), characterized in that the parachute (10) is attached by means of at least one cord (12) in at least one attachment point (9) on the warhead (1), and where the attachment point (9) is arranged on a first rotatable circular disc (3), with said rotatable circular disc (3) being arranged on the upper side of the warhead (1 ).

5. Warhead (1 ) provided with a parachute (10) according to claim 4, characterized in that the first rotatable circular disc (3) is provided in a second rotatable circular disc (5).

6. Warhead (1 ) provided with a parachute (10) according to either of claims 3 or 4, characterized in that the diameter of the first rotatable circular disc (3) lies within the range of 40%-60% of the diameter of the warhead.

7. Warhead (1 ) provided with a parachute (10) according to any of claims 4-6, characterized in that the diameter of the second rotatable circular disc (5) lies within the range of 80%-100% of the diameter of the warhead (1 ).

8. Warhead (1 ) provided with a parachute (10) according to any of claims 4-7, characterized in that the warhead (1 ) is provided with a homing device.

9. Projectile (100), characterized in that the projectile is provided with a warhead (1 ) according to any of claims 4-8, and by the warhead is arranged to be separated from the projectile along the trajectory of the projectile.