Improved Self-Propelled Gun System

The present invention relates to a self-propelled gun system.

In particular it relates to a self-propelled gun system with integral recoil mitigation system.

When artillery systems fire, the gun generates very large recoil forces which must be managed and dissipated. Failing to dissipate the forces leads to the system moving in uncontrolled ways, making them hard to manage and/or dangerous. When firing at low angles the recoil loads may generate an overturning moment which may cause the weapon to jump or even overturn during the shot. Lightweight systems tend to be fixed to the ground e.g. via braked wheels/tracks or spades.

In such systems the recoil forces are managed by recoil systems and the forces can be reduced by increasing the length of the recoil stroke and/or increasing the recoiling mass as, via conservation of momentum, this reduces the recoil velocity and hence energy. However, these features all add weight, making it very hard to create a stable light weight system.

Conventionally, self-propelled gun systems (i.e. those which have a powertrain, but which are lighter than heavy weaponry such as tanks) have wheels, drive and braking systems needed for transit in addition to support systems which deal with the very large impulse directional loads experienced during operation of the gun. This adds to extra weight and complexity, making it harder to achieve a desired weight limit.

Hence a self-propelled gun system which is relatively lightweight and yet stable when absorbing recoil forces is highly desirable.

According to the present disclosure there is provided an apparatus and system as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

Accordingly there may be provided a self-propelled gun system () comprising a chassis () extending along an x-axis, a first end () of the chassis () and a second end () of the chassis () spaced apart from one another along the x-axis. The chassis () may extend along a y-axis, a first side () of the chassis () and a second side () of the chassis () spaced apart from one another along the y-axis. The x-axis is at right angles to the y-axis.

The self-propelled gun system () may further comprise a gun barrel () having a gun barrel axis (), the gun barrel () being mounted to the chassis () by a pivot mount (), the gun barrel () being pivotable relative to the x-axis about a pivot axis () aligned and/or parallel with the y-axis.

The self-propelled gun system () may further comprise a chassis () suspension system () comprising a first wheel arm () extending away from the chassis () to a first wheel (), the first wheel () being rotatably mounted on the first wheel arm (), the first wheel () configured for engagement with, and travelling along, a support surface () to support the chassis (), when in transit, a distance (Dz) apart from the support surface () in a z-axis, the z-axis being perpendicular to the x-axis and y-axis.

The self-propelled gun system () may further comprise a recoil mitigation system () comprising a recoil support leg () which extends away from the chassis () to a foot end (), the foot end () operable to engage with the support surface () during firing of a projectile () from the gun barrel (). The foot end () of the recoil support leg () may be operable to be spaced apart from the support surface () when the gun system () is in transit.

The recoil support leg () may be configured to react against recoil force (Fr) in the z-axis from the firing of a projectile () from the gun barrel ().

The recoil mitigation system () may further comprise a wheel brake control device () configured for applying a braking force to the chassis first wheel () after the firing of a projectile () from the gun barrel () and after the rotatable first wheel () has started rotating along the support surface () in response to the firing of a projectile () from the gun barrel ().

The gun barrel () may be constrained to pivot about the pivot axis () in a plane of movement extending through the x-axis and z-axis. The gun barrel () may be constrained to pivot about the pivot axis () between −5 degrees to the x-axis and +75 degrees to the x-axis.

The gun barrel () may be rotatable about the z-axis, limited to be rotatable no more than +/−5 degrees relative to a direction parallel to the x-axis around the z-axis.

The recoil support leg () may be pivotable and/or extendable between: a first configuration in which the foot end () of the recoil support leg () is spaced apart from the support surface () when the gun system () is in transit; and a second configuration in which the foot end () is engaged with the support surface () during firing of a projectile () from the gun barrel ().

The foot end () of the recoil support leg () may comprise a sledge () configured to frictionally engage with the support surface () to inhibit movement of the chassis () in the x-axis by a recoil force (Fr) from the firing of a projectile () from the gun barrel ().

The foot end () of the recoil support leg () may be defined by a wheel () rotatably mounted to recoil support leg ().

The self-propelled gun system () may further comprise a wheel brake control device () configured for applying a braking force to the recoil support leg rotatable wheel () after the firing of a projectile () from the gun barrel () and after the rotatable first wheel () has started rotating along the support surface () in response to the firing of a projectile () from the gun barrel ().

The wheel brake control device () of the first wheel arm rotatable wheel () and/or recoil support leg () rotatable wheel () may be a regenerative braking device (), magnetic impedance braking device and/or friction braking device.

The regenerative braking device () may be operably linked with a rechargeable electric storage device () and the chassis first wheel () and/or the rotatable wheel () of the recoil support leg () for generating an electrical current by decelerating the chassis first wheel () and/or recoil support leg rotatable wheel () and thereby dissipating the recoil of the gun barrel ().

The self-propelled gun system () may further comprise a processor () in communication with the regenerative braking device () and the rechargeable electric storage device () such that in response to a first movement of the chassis () along the support surface (), the processor () causes the regenerative device () to decelerate the chassis first wheel () and/or recoil support leg () rotatable wheel ().

The chassis first wheel arm () may extend away from the chassis () to the first wheel () at an angle to the x-axis, y-axis and/or z-axis. A resilient suspension unit () may extend between the chassis () and the chassis first wheel arm ().

The gun barrel () may have a front end () and a muzzle () provided towards the front end (). The gun barrel () may have a rear end () and a breech assembly () provided at the rear end ().

The gun barrel () may be coupled to a recoil mechanism () comprising a recuperator () for mitigating a recoil force (Fr) along the gun barrel axis () from the firing of a projectile () from the gun barrel ().

The chassis suspension system () may further comprise a first leg strut (), the first leg strut () pivotably attached to the chassis () at a coupling end (), and extending to a foot () configured for engagement with the support surface () to support the chassis () apart from the support surface ().

The unladen mass of the self-propelled gun system may be no greater than 10 tonnes or no greater than 5 tonnes.

Hence there is provided a self-propelled gun system with a recoil mitigation system configured to react against recoil force in a vertical (z-axis) direction and horizontal (x-axis) direction which is stable and lightweight compared to examples of the related art.

The present disclosure relates to a self-propelled gun systemhaving a recoil mitigation system. This is shown diagrammatically.

The self-propelled gun systemmay comprise a powertrainsuch as an internal combustion engine, electric motor or hybrid motor, wherein the drive may be transferred by an appropriate means (for example, drive shafts) to wheels,. Other apparatus on the systemmay be electrically powered. The wheels,are coupled to and driveable by the powertrainto propel the gun system.

The unladen mass of the self-propelled gun systemmay be no greater than 10 tonnes. The unladen mass of the self-propelled gun systemmay be no greater than 5 tonnes. Hence there is provided a self-propelled gun systemwhich is considerably lighter than a tank, and hence easier to transport and requiring less raw materials to construct.

As illustrated in the figures, the self-propelled gun systemcomprises a chassisextending along an x-axis. A first endof the chassisand a second endof the chassisare spaced apart from one another along the length of the chassisalong the x-axis. The chassisextends along a y-axis along the width of the chassis. A first sideof the chassisand a second sideof the chassisare spaced apart from one another across the width of the chassisalong the y-axis. The x-axis is at right angles to the y-axis.

As shown in, the gun barrelhas a barrel axis, the barrelbeing mounted to the chassisby a pivot mount. The barrelis pivotable relative to the x-axis about a pivot axisaligned and/or parallel with the y-axis.

The barrelmay have a front end, with a muzzleprovided towards the front end. The barrelhas a rear end, with a breech assemblyprovided at the rear end.

As shown in, the gun barrelmay be coupled to a recoil mechanismcomprising a recuperatorfor mitigating a recoil force Fr along the barrel axisfrom the firing of a projectilefrom the gun barrel.

As shown in the end views of, the self-propelled gun systemfurther includes a chassis suspension systemcomprising a first wheel armextending away from the chassisto a first wheel. The chassis first wheel armmay extend away from the chassistowards a support surface(e.g. the ground) at an angle to the x-axis, y-axis and/or z-axis. The first wheelis rotatably mounted on the first wheel arm.

The self-propelled gun systemmay further comprise a second wheel armconfigured, mounted and operable as the first wheel arm. As with the first wheel arm, the second wheel armextends away from the chassis, towards the support surface(e.g. the ground) at an angle to the x-axis, y-axis and/or z-axis, to a second wheel. The second wheelis rotatably mounted on the second wheel arm.

The second wheel armis configured to operate in the same way as the first wheel arm. Hence features and operation of the first wheel armherein described are equally applicable to the second wheel arm, even where the second armis not specifically referenced.

Hence the platform/chassismay be (at least in part) supported on wheels,via a suspension system.

As shown in, the first wheelis configured for engagement with the support surface(e.g. the ground). Hence the first wheel armand first wheelare configured to support the chassis, when in transit, a distance Dz apart from the support surfacein the z-axis, the z-axis being perpendicular to the x-axis and y-axis. Likewise, the second wheelis configured for engagement with the support surface, the second wheel armand second wheelconfigured to support the chassis, when in transit, the distance Dz apart from the support surfacein the z-axis.

Hence the second wheel armand second wheelare configured to support the chassistogether with the first wheel armand first wheelthe distance (Dz) apart from the support surfacein a z-axis.

The first wheel armand second wheel armextend away from each other on opposite sides of the chassis. That is to say the first wheel armand second wheel armare opposite each other across the x-axis. Put another way, the first wheel armextends away from the chassisfrom the first sideof the chassisand the second wheel armextends away from the chassisfrom the second sideof the chassis.

Hence the wheel armand the second wheel armform a pair of wheel arms,to which are attached a pair of wheels,. As shown inthe gun systemmay comprise further pairs of wheel arms,and wheels,. Hence there may be provided two pairs of wheel arms,and wheels,. In other examples, not shown, there may be provided three, four or more pairs of wheel arms,and wheels,along the length of the chassis. Each pair of wheel arms,and wheels,may be spaced apart from the others along the length (i.e. x-axis) of the chassis.

Hence, in such examples, the or each pair of wheel arms,work together to support the chassisthe distance Dz apart from the support surfacein a z-axis.

In some examples, a single wheel armand wheelmay be provided in isolation (i.e. without a corresponding second wheel armand second wheel, for example where the self-propelled vehicle has only three wheels, two of which form a pair opposite one another across the x-axis, and the third being spaced apart from the others along the x-axis.

As shown in, the chassis suspension systemmay further comprise a first leg strut, the first leg strutpivotably attached to a side,of the chassisat a coupling end, and extending to a footconfigured for engagement with the support surfaceto support the chassisapart from the support surface. A second leg strutmay be provided which is attached to, and extends away from, the second sideof the chassis. Such pairs of leg struts may be provided along the length of the chassis. The leg strut(s) are configured to provide additional stability in addition to the wheel arms,and wheels,.

A resilient suspension unitis provided to bias the first wheel arm. Likewise, in examples in which the second wheel armis present, a resilient suspension unitmay be provided to bias the second wheel arm. The resilient suspension unitmay extend between the chassisand the chassis first wheel arm. The resilient suspension unitmay extend between the chassisand the chassis second wheel arm. The resilient suspension units,are provided to bias the first wheel armand second wheel armto move the chassisback to being spaced part from the support surfaceby preferred distance Dz for transit after displacement of the chassisaway from the preferred distance Dz. For example, the displacement may be in response to the chassis moving over rough ground, with the resilient suspension unit,acting to absorb shock/bounce loads as well as maintaining a desired ride height following a shock/bounce load.

That is to say, the chassis suspension systemis configured to position the chassisat a preferred height above the support substratefor transit, for example when the self-propelled vehicle is travelling from one location to another over land.

The resilient suspension units,may comprise at least one of air springs, switchable shock absorbers, hydropneumatic, hydrolastic, and hydragas suspensions. The resilient suspension units,may be configured to vary their spring stiffness. The resilient suspension units,may be configured to vary their damping stiffness.

The gun barrelmay be constrained to pivot about the pivot axisaligned and/or parallel with the y-axis in a plane of movement extending through the x-axis and z-axis. For example, the gun barrelmay be pivotably mounted using a trunnion mount, cylindrical bearing or bushing.