WO1996037753A1

WO1996037753A1 - Demining system

Info

Publication number: WO1996037753A1
Application number: PCT/SE1996/000656
Authority: WO
Inventors: Kjell Jann Haughom
Original assignee: Tonstad Maskinfabrikk A/S; Swedish De Mining Ab; Bofors Ab
Priority date: 1995-05-22
Filing date: 1996-05-21
Publication date: 1996-11-28
Also published as: SE9501898L; SE505197C2; WO1996037753A9

Abstract

The present invention relates to a demining system comprising a carrier vehicle (1) and a demining device (4) that operates in the ground in front of the vehicle and which device, driven by a motor mounted on the vehicle, rotates around a shaft (23) extending transversely and mainly horizontally to the vehicle. The purpose of the demining system in accordance with this invention is to clear large open areas of ground, including undulating terrain, from both buried and unburied mines. To achieve the necessary inclination of, and sufficient power to, the demining device it is powered by a motor mounted in the main beam across the vehicle which main beam connects the two longitudinal beams. The complete framework can then be laterally inclined and tilted relative to the vehicle (1) via a ball coupling (5) mounted close to the centre of gravity of the vehicle, while the lateral forces acting on the demining device are assimilated by a separate traverse steering unit (18-20) mounted between the demining device and the vehicle.

Description

DEMINING SYSTEM

The present invention relates to a complete demining system designed primarily for clearing mines in open land including undulating land to liberate the land from both buried and unburied mines of both the anti-personnel type as well as large area defence and anti-tank mines.

The requirement for the demining system in accordance with the present invention to clear both buried and unburied mines means that it must be able to penetrate ground layers down to the greatest depth at which it can be expected to find active mines, while the requirement to be able to demine undulating terrain means that the device that actually performs the demining operation must be able to be inclined in relation to the carrier vehicle. Moreover, the device must be driven by a powerful force through the ground layers since it not only needs to cope with mines but also with vegetation in the form of roots, bushes, small trees and small stones that may be present. The complete demining system must thus be extremely ruggedly constructed and have an extremely large engine at its disposal.

As the mines that may be found may also be, and in all probability are, of varying size the demining system cannot be dimensioned for the largest mine that could possibly be found but rather for those mines that can be expected to be most common. The demining device must therefore be so designed that in the event of damage occurring from an extremely powerful mine detonation the device is easy to repair. We believe that the demining system in accordance with this invention meets all these requirements.

The demining system in accordance with this invention thus comprises a carrier vehicle with a motor-driven demining device rotating around a mainly horizontal axle mounted in front that operates in the ground ahead of the vehicle. As the complete system shall be used in dangerous mined terrain it is an advantage if the vehicle is robust and fragment resistant. An appropriate alternative would be a chassis from an old main battle tank or armoured combat vehicle. With regard to the actual demining device there is a most excellent basic principle for such a device described in Norwegian patent application 940783. This device is constructed as a disc cultivator comprising a number of cultivator discs mounted parallel to each other on one and the same cylindrical shaft, the outer periphery of each disc being fitted with teeth. The advantage of this device is that the discs when rotated mechanically by a great force have an exceptionally good capability to penetrate ground layers down to a sufficient depth for the purpose intended while crushing and demolishing the mines that are in its path. The intention is thus that the mines in the first instance shall be demolished without detonating, but should they happen to detonate the disc cultivator device is so open that the main part of the explosive force is directed outwards away from the cultivator discs of the device. Should damage be inflicted on the device such damage will be limited and easily repairable since the cultivator discs are constructed in the form of easily separable sectors.

The present invention, however, relates in the first instance to the mounting of the device and to the interconnected parts that together enable the actual demining device to be inclined to a sufficient degree to enable it to function in undulating terrain. The shaft of the demining device is mounted at each end in a beam extending in the longitudinal axis of the vehicle and these two beams have a common pivoting point of ball coupling type in the vicinity of the centre of gravity of the complete demining system, and the angle of these beams relative to the vehicle and thereby also relative to the ground surface is determined by hydraulic cylinders located between the beams and the vehicle, each hydraulic cylinder being between the common pivoting point and the device. This arrangement enables the shaft of the device to be inclined relative to the vehicle while simultaneously the working depth of the demining device in the ground is determined by the setting of each of the beams. To assimilate the lateral forces acting on the shaft of the device in its longitudinal axis there is a traverse steering unit that enables the beams to be raised and lowered and the shaft to be inclined but which prevents lateral motion. This traverse steering unit comprises a cross-beam that interconnects the mounting points of the shaft of the device, and a guide-way located laterally on this cross- beam in which guide-way a pivotable pivot block is engaged. The pivot block is so designed that it allows the necessary inclining of the cross-beam and thereby also of the shaft of the demining device.

The position for the common pivoting point of both beams should naturally lie along the longitudinal symmetry axis of the carrier vehicle. In accordance with a more developed form of mounting of the demining device in accordance with this invention both beams are located along the longitudinal sides of the carrier vehicle and the beams are interconnected by a pivotable main beam extending across the vehicle and mounted on the common pivoting point of the two longitudinal beams. The main beam also houses the drive motor for the demining device and one of the longitudinal beams may be utilised to encapsulate the transmission that is necessary between this drive motor and the actual demining device.

The invention is defined in the subsequent patent claims, and it is described in further detail below with reference to the appended figures.

Figure 1 shows an oblique projection of the complete demining system.

Figure 2 shows a side section of the same system.

Figure 3 shows a more detailed section of the beam arrangement incorporated with the drive for the device indicated together with the traverse steering unit whose task is to assimilate the lateral load forces on the demining device.

Figure 4 shows a section through the actual demining device and its mounting points.

The same parts are identified by the same numbers on the various drawings even though they are of somewhat varying design or are drawn to different scales.

The vehicle shown in the various figures is a main battle tank chassis 1 supplemented with a fragment-protected operator's cabin 2. When the demining system is utilised in the field it will be primarily remotely controlled. A main beam 3 is located across the vehicle 1. The ventilation apertures shown in Figure 1 indicate that the main beam 3 houses the motor that drives the actual demining device 4. This is only indicated in Figure 1. The main beam is mounted on an extremely robust ball coupling 5 that enables both tilting in the longitudinal axis of the vehicle as well as inclination in the lateral axis of the vehicle 1. Two beams 6 and 7 extend from the main beam 3 along the longitudinal axis of the vehicle and the front end of these beams support the device carrier 8 and the actual demining device 4. The setting of the beams 6 and 7 relative to the vehicle 1 and thereby also relative to the ground surface is determined by two adjacent demining device mounts located between the beams and the hydraulic cylinders 9 and 10 located on the vehicle. The hydraulic cylinders 9 and 10 can be set individually which means that the complete rigid system comprising the main beam 3, beams 6 and 7, the demining device carrier 8, and the demining device 4 can be inclined relative to the vehicle for deployment on inclined ground surfaces such as slopes and the sides of ditches. In the same way the cutting depth of the demining device 4 into the ground can be regulated.

As shown primarily in Figure 3, but also in Figure 4, the drive motor located in main beam 3 for driving the demining device is connected to a belt drive 11 located mainly in beam 7 and comprising the drive pulley 12 and the transfer pulley 13. At transfer pulley 13 a second belt drive 14 is engaged to enable the couplings 15 and 16 (see also Figure 4) that connect the beams with the demining device carrier 8 to be employed.

Figure 3 also shows the traverse steering unit whose task is to assimilate the lateral forces acting in a longitudinal direction on the demining device 4. The traverse steering unit is comprised of two traverse steering plates 18 and 19 connected to the cross-beam 17 incorporated in the demining device carrier 8. Only traverse steering plate 19 is visible in Figure 3 together with the pivotable pivot block 20 attached to the vehicle and engaged between the two traverse steering plates 18 and 19.

The actual demining device carrier 8 incorporates as previously stated a cross¬ beam 17 that interconnects both bearings 21 and 22 for the actual demining device consisting of roller 23 equipped with a large number of fixed circular cultivator discs 24 that are each comprised of easily replaceable segments. The outer periphery of each cultivator disc is fitted with a number of teeth 25 of the type shown in Figure 2. The actual demining device can rotate in the direction of drive of the vehicle 1 and can also counter-rotate. The teeth 25 are thus always angled so that it is their points that impact first with the ground. The task of the teeth 25 is to mill to destruction everything that comes in their path — primarily mines.

In Figure 4 the twenty cultivator discs are drawn while the teeth are only indicated to avoid the drawing from becoming unclear. On the other hand, Figure 4 shows a detailed illustration of the transfer between the two belt drives 11 and 14.

It should also be pointed out that Figure 2 shows the actual demining device in the mode utilised for deployment in the ground at maximum depth and rotating counter to the direction of drive of the carrier vehicle 1. The demining device 4 can also rotate in the opposite direction, i.e. in the direction of drive of the vehicle, in which case the direction of the teeth 25 shall be reversed.

Figure 4 also shows a hydraulic reduction gear 26 incorporated into the roller 23 to reduce the revolutions of the drive motor to the desired rate of revolutions for the demining device 4.

Claims

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

1. The demining system comprising a carrier vehicle ( 1 ) with at the front in the main direction of drive of said vehicle (1) a mainly horizontal shaft (23) rotated by means of a motor mounted on the vehicle (1) which motor drives the demining device (4) that operates in the ground in front of the said vehicle (1) wherein the ends of the shaft (23) of the demining device (4) are mounted in bearings (21, 22) on two beams (6, 7) extending forwards in the main direction of drive of the vehicle (1) from a mounting point close to the centre of gravity of the complete system, the angle of each such beam (6, 7) relative to the vehicle being determined by hydraulic cylinders (9, 10) mounted between the beams (6, 7) and the vehicle (1), the bearings of the shaft (23) of the demining device (4) being interconnected by a cross-beam (17) parallel to the shaft (23) and which cross-beam (17) is connected to the front of the vehicle (1) by a traverse steering unit (18-20) enabling upwards and downwards motion but blocking lateral motion and whose task is to assimilate the lateral forces acting in a longitudinal direction on the shaft (23) and to transfer such forces to the vehicle (1).

2. The demining system as claimed in Claim 1 wherein the two beams (6, 7) extending in the main direction of drive of the vehicle are connected to the approximate centre of gravity of the complete system by a ball coupling (5) via a main beam (3) extending across the vehicle and in which main beam (3) the drive motor for the demining device (4) is housed and from which main beam (3) the beams (6, 7) extend along the sides of the vehicle (1) approximately parallel to such sides.

3. The demining system as claimed in Claims 1 or 2 wherein at least one of the beams (6, 7) is utilised to house the transmission (1 1, 14) between the motor mounted in the main beam (3) and the demining device (4).

4. The demining device as claimed in Claim 1, 2 or 3 whereas the actual demining device (4) with the bearings (21, 22) in which the shaft (23) is mounted are connected to the beams by couplings (15, 16) to facilitate road transportation with the vehicle (1) and repair of the demining device (4) and by which the transmission (11, 14) between the motor and the demining device (4) is separable vertically by means of such couplings (15, 16).

5. The demining system as claimed in Claims 1-4 wherein the actual demining device (4) is comprised of a roller rotating around the stated shaft (23) and which roller has a large number of teeth (25) operating in the ground in front of the vehicle (1).

6. The demining system as claimed in Claim 5 wherein the roller (23) incorporates a large number of concentric ring-shaped cultivator discs (24) mounted parallel to each other and around whose periphery there are mounted a large number of individually replaceable teeth (25).

7. The demining system as claimed in Claim 6 wherein the stated ring- shaped discs (24) are comprised of individually replaceable sectors.

8. The demining system as claimed in either of Claims 5-7 wherein a hydraulic gear (26) engaged between the demining device/roller (4) and the drive motor to reduce the rate of revolutions of the motor to the desired rate of rotation for the demining device (4) is incorporated in the roller/shaft (23).

9. The demining system as claimed in Claim 8 wherein the roller/shaft (23) is designed to be fillable with water to a greater or lesser extent as required for cooling of the reduction gear (26) and/or to enable balancing of the demining device (4).