GB2198821A - Gun systems - Google Patents

Abstract

A gun system comprises a gun carried in a carriage, a supporting structure for the carriage having a construction which upon recoil of the gun permits the carriage to move with a controlled curved motion having a vertically upward component relative to the supporting structure. In one embodiment, the gun 1 is mounted in a cradle 3 and has its elevation varied by means of arms 11 the length of which is adjusted by means of a gearbox 17. In order to assist stabilisation of the system upon recoil of the gun, trunnions 5 at the rear of the cradle 3 are allowed to run up a track 7 (for low angles of elevation of the gun, eg below 30 DEG ). Return of the cradle 3 and gun 1 to the firing position may be assisted by return springs or recuperators (not shown). <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 Lll8- (hereinafter referred to as the Wight 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 behind 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 helicpter.

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 comprises a gun carried in a carriage supported on a supporting structure, the support of the carriage on the supporting structure having a construction which upon recoil of the gun permits the carriage and gun to move with a controlled curved motion having a vertically upward component relative to the supporting structure.

The upward motion and acceleration provided by the said construction improves the stability of the system compared with known gun systems by producing a vertical force which counteracts the destabilising weight of the gun. This improved stability allows the gun to be made from components which are lighter in weight compared with those used in known systems since stability is not so dependent on weight of the components as in such known systems. For example, the gun may be balanced by a trail leg arrangement comprising at least a portion made of a lightweight composite material.

The said support may include conventional elevating arms which may be extensible in length and settable at the required length, the arms being connected to the carriage and to the supporting structure by bearings allowing the arms to rotate thus allowing the angle of elevation of the gun to be changed and set as desired.

In a first example of the present invention the said construction may include further elevating arms connected between the supporting structure and the carriage, preferably near its rear end (relative to the muzzle end of the gun), which are rotatable allowing the carriage and gun to rotate upward upon recoil.

In a second example of the present invention the said construction may include trunnions on the carriage, preferably near its rear end, located in complementary rising tracks provided in the supporting structure.

In the said first example the system may include means for locking the further elevating arms and in the said second example the system may include means for locking the trunnions in the tracks, so that when the angle of the gun elevation is greater than a pre-determined minimum, e.g.

300 relative to the ground (assuming the ground to be horizontal) the carriage may be elevated and set in height relative to the supporting structure.

At such elevation angles stability is not such a significant problem. Raising and setting the height of the carriage in this way (which is the subject of a copending application of even date by the present applicants) allows sufficient clearance from the ground to be provided to permit recoil and access by operating crew especially when the gun and carriage are mounted at a low height relative to the ground for low angles of gun elevation.

Following firing of the gun, the carriage may be returned to the position for firing by the action of gravity although this maybe assisted by springs or recuperators attached between the supporting structure and the carriage or the said construction, e.g. the further elevating arms in'the said first example.

The supporting structure may comprise a base, which may be rotatable, and a trail arrangement, e.g. trail legs, to balance the gun about the base. In the said second example the supporting structure may also include a saddle in which the trunnion tracks are provided. The elevating arms may also be attached to such a saddle.

As mentioned above, the gun in the system according to the present invention may be mounted at a low height relative to the ground especially at low angles of gun elevation. This improves stability of the gun by reducing the destabilising moment which reaches a maximum upon firing of the gun; this moment, which tends to tip the gun forward, is proportional to the height of the gun above the ground.

Where the trail arrangement includes legs comprising at least 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, polyamide 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 legs may be straight or curved in overall shape.

The recoil forces produced upon firing the gun may be damped by a known buffer connected between the carriage and gun and the gun may be reset by a known recuperator. The gun system may include known balancing gear and known traversing gear.

The gun system according to the present invention may be a lightweight towable howitzer of large bore, e.g.

155mm. Towing may be possible by wheels stowable during operational use of the system. The system may also be provided with attachments for air lifting, e.g. by helicopter, which is possible from the low weight obtained by the novel construction.

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 a novel gun system.

Figure 2 is a side elevation of an alternative novel gun system.

In Figure 1 a gun 1 is carried in a cradle 3 which is mounted at its rear end by trunnions 5 (one shown in Figure 1) located in a track 7 provided in a saddle 9. The saddle 9 is supported by a support pillar 4 and a base 6. Trail legs 9 attached to the pillar 4 project behind the saddle 9 to balance the gun 1 and the cradle 3 about the base 6.

Elevating arms 11 (one shown in Figure 1) are attached to the saddle 9 by a bearing 13 and to the cradle 3 by a bearing 15 on a front upper bracket on the cradle 3. The arms 11 allow the angle of elevation of the cradle 3 and gun 1 to be varied and set as required. The arms 11 have a variable length and are extended together by a gear box 17. The positions of the arms 11, the cradle 3 and the gun 1 at a high angle of elevation are shown in Figure 1 by broken lines indicated by the symbol E.

The gear box 17 also controls the height of the rear end of the cradle 3 and the trunnions 5 and consequently the rear end of the gun 1. The rear end of the cradle 3 is jacked up by the gearbox 17 (by a mechanism which is hidden in Figure 1) but the vertical distance travelled by the rear end is only a small fraction, e.g. typically a few per cent, of the vertical distance travelled by the front of the cradle 3. The position of the trunnions 5 when the gun 1 is at the position indicated by the symbol E is the position T indicated by a broken line in Figure 1.

The trunnions 5 are preferably locked in position in the track 7 when the desired angle of elevation of the gun 1 is obtained. The track 7 may comprise a series of 'half caps' or dished recesses (not shown in Figure 1) to facilitate locking of the trunnions 5 in a stable position in the track 7.

Each of the elevating arms 11 may comprise a known construction comprising a screw-threaded rod inside an internally screw-threaded sheath (not shown in Figure 1), extension of the arm 11 being achieved by rotation of the rod relative to the sheath.

The saddle 9 shown in Figure 1 may be rotatable in the horizontal plane, i.e. around the pillar 4, to allow the azimuth angle of the gun 1 to be varied.

As in conventional gun systems the trail legs 10 may be anchored in the ground by spades 14 and the base 6 may also be provided with similar anchoring means (not shown) for added stability.

As described in a copending application of even date, the trail legs 10 may be made of one of the lightweight composite materials described above, e.g. a carbon/glass fibre reinforced epoxy resin, although the portion beneath the saddle 9, indicated by reference numeral 21 is preferably made of metal, e.g. stainless steel or a titanium alloy. The trail legs may have a hollow structure which may be approximately box shaped in cross-section.

The gun system may have known components (not shown) such as equilibrating gear for balancing the system when the angle of elevation of the gun (1) is increases, wheels hinged into a stowable position, a muzzle brake for reducing recoil forces and a buffer/recuperator system between the gun (1) and the cradle (3) which damps recoil forces and resets the gun (1) into the firing position after recoil.

In order to assist stabilisation of the system upon recoil the trunnions (5) may be allowed to run up the track (7) for low angles of elevation of the gun (1), e.g. below 300 relative to the base (6). This vertical motion produces a stabilising moment which is increased upon recoil of the gun (1). Return of the cradle (3) and gun (1) to the firing position is achieved by the action of gravity but may be assisted by return springs or recuperators (not shown).

In Figure 2 a gun 44 carried in a cradle 43 is elevated by a pair of elevating arms 45 (one only shown in Figure 2) and a pair of elevating arms 47 (one only shown in Figure 2). The arms 45, 47 are attached by bearings 49, 51 respectively to the cradle 43 and by bearings 53, 55 respectively to a rotatable platform 57 on a base 59.

Trail legs 61 (one only shown in Figure 2) balance the gun 41 about the base 59. The legs 61 have spades 63 to anchor them to the ground. The base 59 may also be anchored in the ground.

The arms 45 attached to the cradle 43 near its rear end are fixed in length whilst the arms 47 attached to the cradle 43 near its front end are variable in length (in the same manner as the arms 11 shown in Figure 1) by a gearbox 65. The bearings 49, 51 allow the arms 45 to rotate relative to the platform 57 and the bearings 53, 55 allow the arms 47 to rotate relative to the platform 57.

The angle of elevation of the gun 41 and the cradle 43 is thus varied by varying the length of the arms 47 and, as this angle is varied, rotation of the arms 45 causes the rear end of the cradle 43 and of the gun 41 to rotate upward giving the desired clearance from the ground G.

This position is indicated by the broken lines labelled E in Figure 2. The arms 45 may be locked to hold the cradle 43 and gun 41 in this position by a known locking mechanism (not shown in Figure 2).

The trail legs 61 may be made of a lightweight composite material, e.g. a mixed glass/carbon fibre reinforced epoxy resin formed in a hollow, e.g.

approximately box-shaped structure (in cross-section).

At low angles of elevation of the gun 41, e.g. below 300 relative to the ground G, the gun 41 and cradle 43 may be allowed to rotate upward upon recoil, thus assisting stabilisation of these components. Control springs or recuperators (not shown) may be connected between the arms 45, 47 and the platform 57 to return the gun 41 and the cradle 43 to their original elevation angle.

The system shown in Figure 2 may have other known components, not shown in Figure 2, similar to those which the system shown in Figure 1 may include.

Claims (8)

Claims:

1. A gun system comprising a gun carried in a carriage supported on a supporting structure, the support of the carriage on the supporting structure having a construction which upon recoil of the gun permits the carriage and gun to move with a controlled curved motion having a vertically upward component relative to the supporting structure.

2. A gun system as claimed in claim 1 and wherein the gun is balanced by a trail leg arrangement comprising at least a portion made of a lightweight composite material.

3. A gun system as claimed in claim 1 and wherein the said support includes elevating arms which are extensible in length and settable at the required length, the arms being connected to the carriage and to the supporting structure by bearings allowing the arms to rotate and allowing the angle of elevation of the gun to be changed and set as desired.

4. A gun system as claimed in claim 3 and wherein the said construction includes further elevating arms connected between the supporting structure and the carriage, near its rear end relative to the muzzle end of the gun, which further arms are rotatable allowing the carriage and gun to rotate upward upon recoil.

5. A gun system as claimed in claim 4 in which the further elevating arms are fixed in length.

6. A gun system as claimed in claim 3 having means for returning the gun and carriage to the position for firing, which means include a spring connected between the carriage and supporting structure.

7. A gun system as claimed in claim 1 and wherein the said construction includes trunnions on the carriage, near its rear end, located in complementary rising tracks provided in the supporting structure.

8. A gun system as claimed in claim 1 and which is substantially as hereinbefore described with reference to the accompanying drawings.