WO1996037752A1

WO1996037752A1 - Method for clearing mines and associated demining system device

Info

Publication number: WO1996037752A1
Application number: PCT/SE1996/000655
Authority: WO
Inventors: Magnus ÖSTHOLM
Original assignee: Tonstad Maskinfabrikk A/S; Swedish Demining Ab; Bofors Ab
Priority date: 1995-05-22
Filing date: 1996-05-21
Publication date: 1996-11-28
Also published as: SE9501899L; SE505190C2

Abstract

The present invention relates to a method for clearing unburied land mines (18) on level ground. The invention is based on the principle that rapidly rotating impact organs (11) shall demolish the mines (18) so quickly that they preferably never have time to detonate. Moreover, the same impact organs (11) shall impel all mine residue thus formed, both explosive and non-explosive, into a collection organ (14) designed for this purpose. The invention also incorporates an associated demining system.

Description

METHOD FOR CLEARING MINES AND ASSOCIATED DEMINING SYSTEM DEVICE

The present invention relates to a method for clearing unburied land mines on flat ground and to an associated demining system of large capacity designed to eliminate surface mines from a mainly flat surface such as surfaced roads and airfield runways.

Nowadays it is technically possible to disperse large quantities of mines from the air over predetermined areas such as sections of road or airfield runways. Although such mines are completely visible to the naked eye provided that they are not concealed by existing vegetation, but even if they lie completely unobstructed on a permanent surface, it is often difficult to detect them from a vehicle in motion and even more difficult from an aircraft that is landing or taking off. It is thus very feasible that mines dispersed from the air completely block a vital road section or an airfield runway during the time that it takes to remove the mines. If this occurs during a specially critical phase of an armed conflict such time may be extremely costly, i.e. it is essential for the faction affected by the mines to take the shortest possible time to remove all such mines from the road or runway affected. There is thus a need for vehicle-mounted mine-clearing devices that can accomplish such a task.

The mine-clearing systems at present available for such a task all work, as far as we have been able to ascertain, on the principle that they hopefully have time to destruct the mine before it has time to detonate and that the pieces of mine resulting and possible non-destructed or non-detonated mines will be thrown to the sides away from the road or runway. The disadvantage of such systems is thus that they do not completely eliminate the mine problem but partially transfer the problem laterally to the area of ground immediately adjacent to the object cleared.

The purpose of the present invention it to offer a complete demining system for flat ground that does not only demolish all mines present on the ground surface but also collects all explosive and non-explosive residue thus formed. The demining system in accordance with this invention and the method employed thus does not transfer part of the problem to the adjacent ground surface but is fully effective over the entire width of the object to be cleared.

In addition to the basic principles indicated above the present invention incorporates an improvement to the impact organs utilised to demolish and remove from the surface to be cleared both mines and pieces of mines from those destructed in such a way as to impart a precise removal direction away from the cleared surface so that such mines and pieces of mines directly or indirectly enter a collection device connected to, or mounted on, the carrier vehicle.

In a specially presented design of the device in accordance with this invention the impact organs are attached to a preferably horizontally mounted rotating shaft in such a manner that when the shaft rotates the impact organs follow concentric circular paths relatively closely adjacent to each other that touch or almost touch the surface of the ground. Correctly designed the impact organs impart a predetermined crescent shaped trajectory to mines, pieces of mines, and other solid material present on the ground surface away from their original position. The invention thus incorporates a collection device designed to at least partially surround the path of the impact organs and which has entry openings designed for the collection function, i.e. such openings shall be designed for the trajectories imparted to the demining residue by the impact organs. It could thus be advantageous to give the collection device a double-shell form surrounding the circular path of the impact organs. The part of the double-shell located closest to the impact organs is made shorter along the edge of the demining device against which the impact organs throw the mines and pieces of mines. In most cases this ought to be at the front in the direction of drive of the carrier vehicle as in most cases it should be more appropriate to enable the impact organs to rotate forwards in the direction of drive of the carrier vehicle. However, the opposite ought to be possible as well.

The invention is defined in the subsequent patent claims, and it is described in further detail in the appended figure showing a side projection of a demining device designed in accordance with this invention but where the actual demining device is partially sectioned to reveal its internal design.

The device shown in the figure comprises a carrier vehicle in the form of a main battle tank chassis 1 on which a fragment-protected operator's cabin 2 is indicated. There is a main beam 3 located transversally across the top of the carrier vehicle 1. This main beam 3 houses the motor that drives the impact organs of the actual demining device. Two beams 4 and 5 extend forwards from the crossbeam 3 of which the figure shows only beam 5. The actual demining device 6 is mounted at the forward ends of the beams 4 and 5. The angle of beams 4 and 5 relative to the ground surface is determined by hydraulic cylinders 7 and 8 located between beams 4 and 5 and the carrier vehicle 1. The figure shows only hydraulic cylinder 8. Reference 9 denotes a traverse steering unit designed to assimilate the lateral forces acting on the demining device 6. Reference 10 denotes a transmission housing enclosing parts of the main power transmission system between the demining device 6, the impact hammers 11, and the motor house in the main beam 3.

There are numerous impact hammers 11 mounted in two rows opposite each other on shaft 12, each row of impact hammers thus counter-balancing the other. The impact hammers 11 rotate around the path shown on the figure as the shaft 12 rotates. As shown on the figure the impact hammers 11 are fitted with obliquely chamfered hammer-heads 13 that are designed so that when they strike a solid object on the ground surface they impart motion in an oblique angle upwards away from the original position of the object and, if possible, simultaneously break the object into small pieces. As also shown on the figure the circular path of the impact hammers is surrounded by a double-shell construction that forms a collection chamber 14 for everything struck by the impact hammers 1 1. The collection chamber also has end enclosures that are not visible on the figure.

The basic concept for the device is thus that all solid objects of any size that are present on the ground surface within the operating width of the demining device 6 will be struck by the impact hammers 1 1 and impelled into the collection chamber 14 which consists of an outer metal plate 15 and an inner metal plate 16. The inner metal plate 16 covers a somewhat shorter sector of the path of the impact hammers 11 than the outer metal plate 15. It is the sector covered by outer metal plate 15 but not by inner metal plate 16 that receives all the material thrown up by the impact hammers 1 1 and which material then slides between the two metal plates 15 and 16 into the collection chamber 14. It should also be pointed out that the demining device 6 is fitted with a support wheel 17 that defines the height of the demining device 6 above the ground surface, and that reference 18 denotes a land mine. To facilitate emptying of the collection chamber 14 the base of said collection chamber can be fitted with an openable emptying hatch 19. It would be appropriate to enable the emptying hatch 19 to be remotely operated as it can be expected that there will be explosive matter and, in some cases, also highly toxic matter in collection chamber 14.

Claims

PATENT CLAIMS

We hereby claim and desire to secure by Letters Patent the following.

1 A method of eliminating unburied land mines (18) lying on primarily flat ground by means of a demining device (6) mounted on the front of a carrier vehicle (1) which demining device (6) incorporates a large number of rapidly rotating impact organs (11) operating immediately above the ground surface as the carrier vehicle (1) progresses and which impact organs (11) are designed to crush mines (18) in their path and to impel such mines (18) and the resultant pieces of mines from their original location in front of the carrier vehicle (1) wherein those parts of the impact organs (11) that pass immediately over the ground surface and are thus designed to strike the mines (18) are so designed and have been given a direction of rotation that the mines (18) and the resultant pieces of mines struck are all impelled towards and into a collection organ (14) mounted on the carrier vehicle (1).

2 A method in accordance with Claim 1 wherein the impact organs (11) are given a circular motion at a tangent to the ground surface while the mines (18) struck by the impact organs (11) and the resultant pieces of mines are imparted with a motion directed away from their original location in the path of the impact organs (11) into an at least partially enclosing collection organ (14).

3 A demining system designed in accordance with the method specified in Claim 1 or 2 to eliminate unburied land mines (18) lying on primarily flat ground such as surfaced roads and airfield runways by means of a demining device (6) mounted on the front of a carrier vehicle (1) which demining device (6) incorporates a large number of rapidly rotating impact organs (1 1) operating immediately above the ground surface as the carrier vehicle (1) progresses and which impact organs (1 1) are designed to crush mines (18) in their path and to impel such mines ( 18) and the resultant pieces of mines from their original location in front of the carrier vehicle ( 1 ) wherein those parts of the impact organs (1 1) that pass immediately over the ground surface and are thus designed to strike any mines (18) in their path are so designed and have been given a direction of rotation that the mines (18) and the resultant pieces of mines struck are impelled towards and into a collection organ (14) which is either incorporated in the demining device (6) or is mounted on the carrier vehicle (1).

4 A demining system in accordance with Claim 3 wherein the incorporated demining device (6) comprises a mainly horizontally mounted motor- driven rotating shaft (12) along which a number of impact organs (11) mounted such that as said shaft (12) rotates the free end of each impact organ (11) extends radially from said shaft (12) and follows a concentric circular path tangential to the ground surface while that part of the demining device (6) facing away from the ground surface is at least partially surrounded by a double shell (15, 16) the wall cavity of which forms the collection organ (14).

5 A demining system in accordance with Claim 4 wherein the impact organs (11) are so distributed along shaft (12) that every part of the surface over which the demining device (6) passes as the carrier vehicle (1) moves forwards shall be swept by an impact organ designed to impel mines (18) and pieces of mines present on the ground surface between the double walls (15, 16) of the collection organ.

6 A demining system in accordance with Claim 5 wherein each impact organ (11) at its free outer end has an obliquely chamfered hammer-head (13) the front edge of which in its own direction of rotation is designed to impel the mines (18) and pieces of mines into the opening between the double shell (15, 16).

7 A demining system in accordance with Claim 6 wherein the outer metal plate ( 15) of the collection organ (14) extends further down in front of the path of the impact organs (1 1) than the inner metal plate (16) to form an opening between the two plates (15, 16) leading into the collection organ (14). 8 A demining system in accordance with Claims 3-7 wherein the actual demining device (6) is fitted with one or more support wheels (17) to define the exact height of the demining device (6) above the ground.