GB2198823A

GB2198823A - Gun systems

Info

Publication number: GB2198823A
Application number: GB08627898A
Authority: GB
Inventors: Anthony Charles Buxton
Original assignee: Royal Ordnance PLC
Current assignee: BAE Systems Global Combat Systems Munitions Ltd
Priority date: 1985-11-21
Filing date: 1986-11-21
Publication date: 1988-06-22
Anticipated expiration: 2006-11-21
Also published as: SE8703581D0; NO864614L; AU6571286A; GB8627898D0; IT8748322A0; BE105T1; DE3644910A1; NL8615012A; FR2620211B1; IT1218160B; GB2198823B; SE8703581L; FR2620211A1

Abstract

A gun system in particular a towable howitzer has a cradle assembly 3 carring a gun 1, a base structure 13, and trail legs 11 having a forward portion connected to the base structure 13, a rear portion adjacent the ground and a raised intermediate portion to which the cradle assembly 3 is pivotally mounted at 7. The gun cradle 3 is elevated by means of elevating arms 41 which are locked against the trail legs 11 (in position 41a) when the system is in a transportation configuration. In this configuration support rails 5 are raised to position 5a and the gun 1 is retracted to position 1a along the rails 5. Alternatively (Fig.4, not shown), the gun 1 may be rotated about trunnions 7, (11) to such a position. The raised intermediate portion of the trail legs 11 relative to the height of the centre of gravity of the cradle (gun maintains stability of the system under recoil. <IMAGE>

Description

GUN SYSTEMS The present invention relates to gun systems especially towable howitzer systems.

The artillery gun system known as the British Light Gun L118 (hereinafter referred to as the "Light Gun") is a widely known artillery gun system manufactured and sold by the present applicant company. The structure of this system comprises a gun carried in a cradle on a carriage support comprising a saddle mounted on a short pintle, the gun being balanced about the pintle by a trail arrangement comprising tubular legs projecting to the ground behing the gun. The pintle is fixed on a platform to which the trail legs are also attached, the platform being supported on axles carrying wheels which allow the system to be towed when necessary.

The Light Gun has a very convenient lightweight construction which allows the system to be towed by a land vehicle or transported by helicopter.

However, it is desirable for use in certain applications to provide a novel gun system construction which offers further savings in weight, relative to the size of gun, compared with known systems constructions such as that of the Light Gun.

According to the present invention a gun system including a gun, a cradle upon which the gun is mounted, a base structure and a trail having a forward portion -connected to the base structure, a rear portion adjacent the ground and a raised intermediate portion to which the cradle is pivotally mounted.

Preferably the cradle is attached directly to the trail which may comprise trail legs. The method of attachment may be by trunnion pins about which the gun and carriage can be elevated.

The raised intermediate portion of the trail legs may be curved in a bow shape so as to project towards the ground behind the base structure, the trail legs being such as to reach the height above the ground sufficient to enable the trail legs to flex during firing of the gun and thereby absorb a significant porportion of the recoil energy.

The forward end of the trail legs may be attached directly to the base structure preferably by means of a coupling allowing relative pivoting motion between the trail legs and the base structure. The coupling may compose a ball and socket joint.

As in conventional gun systems the rear end of the gun is carried in a carriage, e.g. a cradle, and may be elevated by extensible elevating arms connected to the carriage.

In the gun system according to the present invention no saddle (as used in conventional systems such as the Light Gun) is necessary to support the elevating mass comprising the gun, any carriage in which the gun is carried at its rear end, and any other components connected to the gun and the carriage. This beneficially allows a reduction in weight to be obtained, relative to the size of the gun, as compared with known systems. Furthermore, the system according to the present invention may be constructed so that the elevating mass has a low centre of gravity when the gun is in the firing position. This enhances stability, especially upon recoil caused by firing of the gun, and consequently permits the system to be constructed using lightweight components.

The relative movement between the trail and the base structure allows the gun to be traversed without moving or rotating the support structure. Generally field guns which are described as examples of this invention only have a limited traversing movement.

The rear portion of the trail legs distant from the base structure may be attached to 5 spades anchored to the ground. Preferably means are provided for permitting horizontal movement of the rear portion of the trail without moving the spades, to enable traverse of the gun. In one arrangement the rear portion of the trail legs are slidably attached to the spade. It is possible for the rear portion of the trailing arms to have a common spade and a common means for permitting horizontal movement of the rear portion of the trail relative to the spade.

The gun system according to the present invention may incorporate means for locating or stowing the gun and cradle in a rearward position between the trail legs, which may include support rails located between the trail legs by which the gun and cradle can-be retracted. The cradle may be mounted on the rails near its rear end (relative to the muzzle end of the gun) by trunnions on the rails and may be mounted near its front end on the rails by further mounting pins similar to the trunnions.

The trunnions may also be located in location caps provided in plates attached to the trail legs to bring the gun into a position for use.

The cradle may be elevated about the trunnions in this position thus varying the angle of elevation of the gun.

A conventional buffer and recuperator may be connected between the gun and the cradle respectively to damp the recoil forces produced upon firing and to relocate the gun in the firing position after recoil respectively.

The cradle may be elevated by extensible elevating arms which are pivotally attached to the trail legs or to the base structure and are pivotally attahced to the cradle. The arms may be stowable in a position adjacent to the trails and may be lockable in that position. Preferably the arms may be locked in that position by a quick release mechanism to allow the arms to be swung into position to connect with the cradle when the gun is in a position ready to be elevated.

The support rails may run parallel to the axis of symmetry of the trail arrangement. The support rails may be provided adjacent to but outside the trail legs relative to the axis of symmetry of the trail arrangement. Preferably the support rails may be lowered when the gun is in its firing position to facilitate access of operating crew to the breech end of the gun.

Preferably, the system is towable behind a land vehicle by wheels which are preferably adjacent to the base structure, e.g. behind the base structure (relative to muzzle end of the gun in the firing position). The wheels may be hinged into a stowed position when the gun is in use. The attachment to the towing vehicle is preferably at the spade end of the trail legs. The system may also include attachments permitting air lifting, e.g. by helicopter.

Preferably, the base structure comprises a base which may be anchored in the ground and a platform or plate rotatable about the axis of the base by a coupling between the two. The trail legs may be attached to the platform or plate.

As an example of the use of lightweight components the trail legs and/or the support rails may be made of, or at least incorporate portions comprising high strength lightweight materials, e.g. lightweight composite material.

The portions and attachments of the trail legs supporting the gun, are however preferably made of metal. For example, where the trunnions supporting the gun and its cradle are located in plates fixed to the trail legs when the gun is in its firing position the plate and the portions of the legs to which they are attached are preferably made of high strength metal, e.g. steel or titanium alloy.

Where the trail legs comprise a portion made of a composite material this portion of the legs may be formed of any known high strength composite material. For example it may comprise any known reinforcing fibres e.g. selected from one or more of carbon, glass, aramid, metal or polyolefin fibres set in a polymeric matrix material which may be a curable, e.g. thermosetting, plastics material or thermoplastic material as is well known to those skilled in the composites art. The reinforcing fibres may be woven or unwoven and their direction may be selected to give directional strength matched to the loads to be applied.

Fibre reinforced plastics layers may be formed into a known laminate structure together with other layers, e.g.

other fibre reinforced plastics with different reinforcing fibres or with fibres orientated differently, non-reinforced plastics or metal layers e.g. of aluminium or titanium.

The trail legs, if comprising a portion formed from any of the above composite materials, are preferably tubular of approximately square, rectangular, circular or any other convenient cross-section. The area enclosed by the tubular shape in cross-section may taper along the length of the leg.

The support rails, if made of a composite material, may comprise one of the materials described above, although if the rails are tubular, the cross-sectional area may be less that that of the trail legs.

The gun system according to the present invention may comprise a lightweight air towable, e.g. helicopter towable, large calibre, e.g. 105mm or 155mm, field howitzer.

An alternative means for locating or stowing the gun and cradle in a rearward position between the trail legs are adapted to permit rotation of the gun about an axis perpendicular to the axis of the gun whereby the gun may be rotated to a position between the trail legs.

Rotation of the gun allows the gun to be stowed between the trail legs and transported by a land or air vehicle in that position.

The system may for example include wheels which may be retracted into a position above the ground when the gun is in use. The wheels may for example be mounted on extensible, e.g. telescopic, arms connected to the rear of the base structure.

The means adapted to permit rotation may be attached to the trail legs. Such means may comprise trunnions and elevating arms attached directly or indirectly to the trail legs. Such attachment of the elevating arms is preferably above the attachment of the trunnions when the system is in use. The gun may be carried in a known carriage, e.g.

cradle, which may include the trunnions and which may be elevated by the elevating arms. The gun is thus rotatable about the trunnions.

The trunnions may be attached to the trail legs by plates, fixed to the trail legs, in which location caps for the trunnions are provided.

The elevating arms in this example of the invention may be extensible by a mechanism comprising a cylinder incorporating a piston which may be pushed outward from inside the cylinder. The pistons may be pushed hydropneumatically by pressure from a pump which may be a hand or machine operated pump. This typically operates at a peak pressure of 104 psi (6.9 x 107 Nm 2) providing delivery to the cylinders at a typical rate of 120in3 per minute (1.97 x 106mm3 per minute) and for example is capable of rotating in less than 2 minutes a typical 0 elevating mass from a position at an elevation angle of 5 (relative to the forward horizontal axis) to an elevation angle of 1750 (i.e. 50 above the rearward horizontal axis).

The cylinders of the elevating arms may be attached to the respective trail legs by bearings permitting rotation of the cylinders about the bearings in a plane parallel to the plane of symmetry between the trail legs. The pistons of the elevating arms may be attached to the cradle, on opposite outside faces thereof, by bearings permitting rotation of the pistons.

Preferably, the system comprises wheels, mounted on extensible arms attached to the base structure, which are stowable during field use of the system, i.e. when the gun is in position for firings, but which wheels may be lowered by extending the arms to enable the system to be transported with the gun positioned between the trail legs.

Preferably, where the trunnions are located in support plates attached to the trail legs, the support plates and optionally the adjacent portions of the trail legs, are made of a high strength metal, e.g. stainless steel or titanium alloy.

Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a side elevation of one example of a novel gun system.

Figure 2 is a plan view of the gun system shown in Figure 1.

Figure 3 is an end elevation (as seen from the front end) of the gun system shown in Figure 1.

Figure 4 is a side elevation of another example of a gun system.

Figure 5 is an end elevation (viewed from the front end) of the gun system shown in Figure 1.

Figure 6 is a plan view of the gun system shown in Figure 4.

As shown in the drawings 1-3 a gun 1 is carried in a cradle 3 which may be supported on support rails 5 (when in a position indicated by broken lines denoted by reference numeral 50) by trunnions 7 at the rear end of the cradle 3 and by pins 9 nearer the front end of the cradle 3.

Trail legs 11 project upward from a base structure 13, the legs 11 curving above the rails 5 and then toward the ground behind the rear ends of the rails 5. The legs 11 are pivotally attached at that end to a common spade 15 which may be anchored in the ground.

The base structure 13 comprises a base 17 having tangs 23 which may be inserted in the ground, a platform 19 above the base 17 coupled to the base 17 by a ball and socket coupling 21 allowing the platform 19 to be rotated relative to the base 17. The legs 11 are fixed to the platform 19.

The rails 5 may be raised and lowered by a pair of support arms 27. The support arms 25 are pivotally attached to a base member 29 and the support arms 27 are pivotally attached to a base member 31. The arms 25, 27 run along slots 33, 35 respectively privided in the rails 5 and may be locked in the slots 33, 35 in the fully raised position of the rails 5 (the support arms being shown in this position by broken lines indicated by reference numerals, 25a and 32a respectively in drawings 1 - 3).

There are essentially two configurations of use of the system as shown in the drawings, the transportation configuration and the field use (i.e. gun use) configuration.

In the transportation configuration the elevating mass comprising the cradle 3 and the gun 1 is in the retracted position indicated by the broken lines denoted by reference symbols 3a and la at the rear end of the rails 5.

The rails 5 are fully elevated. Wheels 37 are attached by arms 39 to a post 41 fixed to the platform 19. The wheels 37 are lowered to the ground to lift the base structure 13 and an attachment (not shown) to the spade 15 is hooked onto the land towing vehicle (not shown) thus lifting the rear end of the system ready for towing. The system also may be air lifted in this configuration.

In order to change to the field use configuration, the wheels 37 are raised and the base 17 is lowered. The spade 15 is rotated until the axis of the system is pointing in the required direction. The spade 15 i-s then anchored into the ground. The elevating mass comprising the cradle 3 and the gun 1 is then moved forward along the rails 5.

During this motion, which may be assisted by a winch mechanism (not shown) the cradle 3 and gun 1 are supported on the rails 5 by the trunnions 7 and pins 9. When the gun 1 reaches its forward or battery position the trunnions 7 are fixed in location caps 8 in plates 10 attached to the trail legs 11. Elevating arms 41 which are locked agains the trail legs 11 in the transportation configuration (indicated by reference numeral 41a in that configuration) are released from catches 43 and are pivoted forward about bearings 45 on an axle 46 (Figure 3) until they connect with location bearings 47 providing pivotal attachment of the arms 41 to the cradle 3. The elevating arms 41 may then act in the same way as conventional arms to raise the front end of the cradle 3 to change the angle of elevation of the gun 1.Essentially, the length of the arms 41 is extended to increase the elevation angle of the gun 1. When the gun 1 is in the firing position the support rails 5 may be lowered to allow operating crew access to the rear end of the gun, to permit loading of the breech (not shown) at that end.

Upon firing of the gun 1 the recoil forces producted are dam,ped by a known buffer 49 (Figure 3) connected between the gun 1 and the cradle 3. The construction of the trail legs 11 relative to the height of the centre of gravity of the elvating mass comprising the cradle 3 and the gun 1 maintains stability of the system under recoil. The gun 1 is restored to its firing position after recoil by a known recuperator 5 (Figure 3).

The composite portions of the trail legs 11 may be formed as hollow tubular sections for example by wrapping glass and carbon-fibre impregnated epoxy pre-preg layers around a mandrel whose cross-sectional shape is the same as the desired sections, the composite being formed by curving the epoxy resin by moderate heating as is well known to those versed in the composites art.

In the second embodiment of the invention illustrated in drawings 4 - 6, a gun 1 carried in a cradle 3 is supported by support attachments to trail legs 5 which are made from a lightweight composite material. The support attachments comprise extensible elevating arms 9 pivotally attached by bearings 8 to the trail legs 5 and by bearings 10 to the cradle 3 and also trunnions 11 located in locating caps 12 in metal plates 13 fixed to the legs 5.

The trail legs 5 are bow shaped and project upward from a base structure 15 which comprises a platform 17 rotatable on a base 19 by a ball joint coupling 21. The trail legs 5 are fixed to the platform 17. The rear ends of the trail legs 5 are attached to a common spade 23 anchored in the ground. The trail legs 5 reach a height above the ground which is greater than that of the centre of gravity of the elevating mass comprising the cradle 3, the gun 1, a known buffer 25 and recuperator 7 attached between them and the elevating arms 9.

The gun system shown in the drawings 4 - 6 essentially has two use configurations, transportation and field use.

In the field use configuration, the system is as shown in the drawings 4 - 6 with the base structure 15 and spade 23 anchored in the ground. Tangs 24 on the base 19 permit anchoring of the base structure 15.

The spade 23 has been rotated, prior to anchoring, about the base structure 15 so as to point the gun 1 in the required direction. The arms 9, which are hydopneumatically extended, are set at a length selected to give the necessary angle of elevation of the gun 1.

Upon firing of the gun 1 the recoil forces produced are damped by the buffer 25 and are absorbed by the cradle 3 and the trail legs 5. The centre of gravity of the elevating mass comprising the gun 1, the cradle 3, the buffer 25, the recuperator 27 and the elevating arms 9 is below the height reached by the trail legs 5 and this maintains stability of the system upon recoil as described above.

In order to change to the transportation configuration the elevating arms 9 are extended the the gun 1 then rotated until the gun 1 points vertically upward after which the length of the arms 9 is gradually reduced, rotation of the gun 1 continuing until the gun 1 and cradle 3 reach the position between the trail legs 5 as indicated by the broken lines denoted by the reference numerals la and 3a in Figure 4. The gun 1 is then secured to the spade 23 by a quick release clamp 33. A hook (not shown) on the spade 23 is then hitched to a towing vehicle (not shown) thus lifting the system at the rear end (the end at which the spade 23 is fitted). Wheels 35 are attached by telescopically extending cantilever arms 37 to a post 39 provided on the platform 17, the wheels 35 being maintained in a stowed position in the field use configuration, are lowered for the transportation configuration by extending the arms 37. This is the position indicated by the broken line denoted by reference numeral 35a in Figure 4. Lowering the wheels 35 raises the base structure 15 off the ground and allows the system to be towed on the wheels 35.

The composite portions of the trail legs 5 may be formed as hollow tubular sections for example by wrapping glass and carbon-fibre impregnated expoxy pre-preg layers around a mandrel whose cross-sectional and overall shape is the same as the desired sections, the composite being formed by curing the epoxy resin by moderate heating as is well known to those versed in the composites art.

Claims

1. A gun system including a gun, a cradle upon which the gun is mounted, a base structure and a trX having a forward portion connected to the base structure, a rear portion adjacent the ground and a raised intermediate portion to which the cradle is pivotally mounted.

2. A gun system as claimed in claim 1 in which the cradle is directly mounted on the trail by means of a trunnion pin.

3. A gun system as claimed in claim 1 wherein the trail comprises trail legs having raised intermediate portions curved in a bow shape so as to project towards the ground behind the base structure, the trail legs being such as to reach a height above the ground which is sufficient to enable the trail legs to flex during firing of the gun and thereby absorb a significant proportion of the recoil force.

4. A gun system as claimed in claim 3 in which the trail legs are made of, or at least incorporate portions comprising high strength lightweight composite material.

5. A gun system as claimed in claim 1 wherein the forward portion of the trail is attached directly to the base structure by a coupling allowing relative pivotal movement between the trail and the base structure.

6. A gun system as claimed in claim 5 wherein the coupling comprises a ball and socket joint.

7. A gun system as claimed in claim 5 having a spade attached to the rear portion of the trail for fixed engagement in the ground, and means for permitting movement of the rear portion of the trail relative to the spade, in a substantially horizontal plane for traversing the gun.

8. A gun system as claimed in claim 7 in which the rear portion of the trail is slidably attached to the spade such as to allow movement of the rear portion of the trail relative to the spade in a substantially horizontal plane.

9. A gun system as claimed in claim 1 in which the trail comprises trail legs and means for locating the gun and cradle in a rearward position between the trail legs when not required for firing.

10. A gun system as claimed in claim 9 wherein the said means include support rails located between the trail legs by which the gun and cradle can be retracted.

11. A gun system according to claim 10 in which the cradle is mounted on support rails near its rear end in relation to the muzzle end of the gun by trunnions on the rails and mounted near the front end on the support rail by mounting pins.

12. A gun system as claimed in claim 11 wherein the trunnions are also located in location caps provided in plates attached to the trail legs to bring the gun into a position for use.

13. A gun system as claimed in claim 10 wherein the cradle is elevated by extensible elevating arms which are pivotally attached at one end to the trail legs or to the support structure, and are pivotally attached at the other end to the cradle.

14. A gun system as claimed in claim 13 wherein the elevating arms are stowable in a position adjacent to the trail legs, which trails are lockable in the position by a quick release mechanism to allow the elevating arms to be swung into position to connect with the cradle when the gun is in a position ready to be elevated.

15. A gun system as claimed in claim 10 wherein the support rails may be lowered when the gun is in the firing position to facilitate access of operating crew to the breach end of the gun.

16. A gun system as claimed in claim 9 wherein said means are adapted to permit rotation of the gun about an axis perpendicular to the axis of the gun whereby the gun may be rotated to a position between the trail legs.

17. A gun system as claimed in claim 16 wherein the means adapted to permit rotation are attached to the trail legs.

18. A gun system as claimed in claim 17 wherein the means adapted to permit rotation comprises trunnions and elevating arms attached directly or indirectly to the trail legs, the attachment of the elevating arms being above the attachment of the trunnions when the system is in use.

19. A gun system as claimed in claim 18 wherein the trunnions are attached to the trail legs by plates fixed to the trail legs, in which plates location caps for the trunnions are provided.

20. A gun system as claimed in claim 1 and which includes wheels to transport the system which may be retracted into a position above the ground when the gun is in use.

21. A gun system substantially as hereinbefore described with reference to the accompanying drawings number I to 3.

22. A gun system substantially as hereinbefore described with reference to the accompanying drawings number 4~ to 6 6