AU2020222084A1

AU2020222084A1 - Ammunition conveyor and turret comprising such a conveyor

Info

Publication number: AU2020222084A1
Application number: AU2020222084A
Authority: AU
Inventors: Yves Martinez
Original assignee: Nexter Systems SA
Current assignee: Nexter Systems SA
Priority date: 2019-02-14
Filing date: 2020-02-12
Publication date: 2021-09-02
Also published as: WO2020165792A1; EP3924682A1; PL3924682T3; KR20210134903A; FR3092907B1; EP3924682B1; FR3092907A1; IL285469A

Abstract

The invention relates to an ammunition conveyor (104) incorporating a wedging device (1) and to a turret comprising such a conveyor with a cradle (2) intended to contain an ammunition (200), immobilising it with wedges (3) distributed around it. The wedges (3) can slide radially between a position engaged in the cradle (2) and a position disengaged from the cradle (2) against the action of a resilient means (4) bringing the wedges (3) into the engaged position. Each wedge (3) can be locked in the engaged position by the action of at least one cam (8) rigidly attached to the conveyor (104) and having an inclined surface (6) cooperating with at least one inclined plane (5) borne by the wedge (3). The inclined surfaces (6) and planes (5) are disposed such that a translation of the cam (8) controlled by an actuator (10) causes a radial translation of the wedge (3). Each wedge (3) is thus squeezed between the cam (8) and the ammunition (200) and ensures the immobilisation of the ammunition (200) with respect to the cradle (2).

Description

AMMUNITION CONVEYOR AND TURRET COMPRISING SUCH A CONVEYOR

The technical field of the invention is that of ammunition

conveyors incorporating an ammunition wedging device.

Autoloading systems for large-calibre weapons generally

have at least one ammunition magazine that is used to feed a

weapon. The transfer of each piece of ammunition between the

magazine and the weapon is done by means of a motorized

conveyor.

Such a device is described in patent DE3328208 where a

military vehicle turret has two revolving cylinder magazines.

Each magazine has a tubular conveyor that collects a piece

of ammunition from a cell in the magazine and aligns it with

the weapon's bore to chamber the piece of ammunition.

During the transfer of the piece of ammunition, it is

placed in a cradle on the conveyor, which holds it

approximately in place. This is not satisfactory as the piece

of ammunition may move due to jolts caused by the transport or

the dynamic movements of the transferring means.

The piece of ammunition then is likely to be misplaced in

the cradle, fall out, be damaged, or be incorrectly arranged

at the weapon, which can lead to jamming and safety problems.

Patent FR2572172 discloses a container for transporting a

piece of ammunition from a manufacturing unit to a storage

reserve and from this storage reserve to the breech of a

weapon. The container comprises a rigid casing carrying radial

wedges angularly distributed around the longitudinal axis of

the casing. When the container and its casing are positioned

in a weapon, a rammer moves the entire container and casing

and stops halt bars of the container, which bars remain

stationary relative to the container, causing the ammunition

wedges to be released. Once the piece of ammunition is loaded,

the container is ejected from the weapon.

Such a container is not suitable for permanent installation in a weapon to form a conveyor that can be associated with, for example, the turret described in patent DE3328208. Ammunition cannot be introduced into an empty container from the front of the container when the bars are engaged as the wedges would then impede the entry of the piece of ammunition. The release of the wedges would require providing, in the vicinity of a loading cylinder, an alternative means for removing the bars, which would impair the compactness of the conveyor. Furthermore, the bars cannot be moved independently of the container's movement. The invention proposes to implement an ammunition conveyor that solves the problems encountered in the prior art. Thus the conveyor according to the invention can be associated with a turret comprising rotatable magazines and ensures a wedging of the transported piece of ammunition while allowing a displacement of the piece of ammunition in both directions with respect to the conveyor. The invention thus relates to an ammunition conveyor comprising a cradle intended to contain a piece of ammunition, the conveyor being characterized in that it comprises wedges evenly distributed angularly around a longitudinal axis of the cradle, said wedges being able to slide radially, through openings, between a position engaged in the cradle and a position disengaged from the cradle by introduction of a piece of ammunition which pushes on the wedges and against the action of at least one elastic means bringing the wedges back into the engaged position, each wedge being lockable in the engaged position by the action of at least one cam secured to the conveyor and having an inclined surface cooperating with at least one inclined plane carried by the wedge, the inclined surfaces and inclined planes being arranged so that an axial translation of the cam, controlled by an actuator, causes a radial translation of the wedge, each wedge then being wedged between the cam and the piece of ammunition and ensuring the immobilization of the piece of ammunition relative to the cradle. According to a characteristic of the invention, the cradle can translate longitudinally relative to the conveyor, the translation of the cradle allowing the wedges to be moved away from their cams which are secured to the conveyor, which unlocks the wedges and allows the piece of ammunition to slide on the cradle. According to another characteristic, the cradle may comprise two groups of wedges, a first group being formed of substantially parallelepipedal wedges comprising a flat face which is applied to the external cylindrical surface of the piece of ammunition and which will ensure radial immobilization of the piece of ammunition, and a second group of wedges which each comprise a tooth profile intended to cooperate with a groove in the piece of ammunition to ensure axial immobilization of the latter. Advantageously, the parallelepipedal wedges of the first group of wedges may each have two inclined planes, each inclined plane being arranged at one longitudinal end of the wedge. The invention also relates to a turret for military vehicle, comprising at least one ammunition magazine comprising a plurality of parallel cells and an ammunition conveyor according to the preceding characteristics, the turret being characterized in that the conveyor is mounted so as to be pivotable around an axis and can be placed in a first position coaxial with a cell of the magazine in order to collect a piece of ammunition therefrom and a second position coaxial with a tube of a weapon of the turret in order to allow loading.

In a particular embodiment, the magazine may include an extraction means for pushing a piece of ammunition out of the cell and into the cradle when the latter is coaxial with the cell of the magazine at which the extraction means is placed. Advantageously, the magazine may be in the form of a cylinder. In a particular embodiment, the turret may comprise two cylinders arranged symmetrically on either side of a vertical plane passing through the axis of the weapon. Advantageously, the extraction means may comprise a pusher chain. According to a particular embodiment, the conveyor of the turret may comprise a pusher allowing, in its second position, the piece of ammunition placed in the cradle to be positioned in the tube of the weapon, the pusher causing the translation of the cradle along the conveyor until it is positioned in the vicinity of the tube of the weapon, as well as the unlocking of the wedges. The invention will be better understood upon reading the following description, which is made with regard to the attached drawings, in which:

[Fig. 1] shows a top view of a turret according to the invention, equipped with a conveyor according to the invention.

[Fig. 2] shows a cross-sectional view of a wedging device of the conveyor according to the invention, the cross-section being along the transverse plane whose trace BB is indicated in Fig. 3.

[Fig. 3] shows a cross-sectional view of a wedging device of the conveyor according to the invention, with the wedges in the engaged position, the cross-section being along the intersecting planes whose trace AA is indicated in Fig. 2.

[Fig. 4] shows the same cross-sectional view as Fig. 3, with the wedges in a partially disengaged position.

According to Figure 1, a turret 100, fitted to an armoured vehicle not shown, comprises a large-calibre weapon 101 as well as two rotatable magazines 102a and 102b of the cylinder type, each comprising cells intended to contain ammunition (ammunition not visible). The cylinders 102a and 102b are arranged symmetrically on either side of a vertical plane passing through the axis of the weapon 101 and are arranged such that each cylinder 102a and 102b can pivot each of its cells to an angular position, known as the loading position, in which the longitudinal axis of the cell 01 or 02 converges towards a pivot point 103 of an ammunition conveyor 104. Around this vertical pivot axis 103, the conveyor 104 can therefore be alternately aligned with a cell of a first cylinder 102a which is in a loading position and then with the tube of the weapon 101 (for a given aiming elevation) and then with a cell of the second cylinder 102b which is also at a loading position. Each cylinder 102a and 102b comprises an ammunition extraction means 105 which comprises a pusher chain 105. The function of the pusher chain 105 is to push on a front part of a piece of ammunition (e.g. a warhead of a piece of ammunition 200 shown in dotted line in Figure 1) located in a cell 102c in loading position so as to place the piece of ammunition 200 in the conveyor 104 when the latter is aligned with respect to the cell (the different positions of alignment of the conveyor with respect to the cells are shown in dotted lines). Once this has been done, the pusher chain 105 returns to an initial position where it is outside the now empty cell 102c, allowing the cylinder 102a or 102b to be rotated if necessary, so as to present at the loading position another cell 102c containing another piece of ammunition.

Such an extraction means 105 which pushes the piece of

ammunition allows for a quick and safe extraction as the piece

of ammunition is pushed in a direction where it is robust, as

opposed to the tensile stresses on the base of the piece of

ammunition which would risk damaging the ammunition's

combustible case, which is designed to resist compression above

all.

Of course, the push should preferably be made around the

warhead of the projectile by a suitably shaped finger. For a

sub-calibre kinetic-energy projectile, the push will be made

around the front part of the sabot.

As can be seen in Figures 2, 3 and 4, the conveyor 104

comprises a wedging device 1 for a piece of ammunition 200,

which is intended to secure the transport of a piece of

ammunition 200 located in the conveyor 104, during the vehicle

mobility and fire phases or during the phases of weapon feeding

from one of the cylinders.

To that end, according to Figure 3, the device 1 of the

conveyor 104 comprises a cradle 2 having a tubular or partially

tubular shape. The cradle 2 is able to slide longitudinally

relative to the conveyor 104 in order to compensate for the

distance D visible in Figure 1 when loading the piece of

ammunition into the weapon. The cradle 2 is thus configured as

a carriage that can move relative to the conveyor 104 on guide

bushes.

According to Figure 2, the device 1 comprises wedges 3

evenly distributed angularly around the longitudinal axis X of

the cradle 2 and passing through radial openings 11 of the

cradle 2.

The wedges 3a, 3b are radially slidable between a position

engaged in the cradle 2 and a position disengaged from the

cradle 2 against the action of at least one elastic means 4

bringing the wedges back to the engaged position.

Advantageously, the device comprises two groups of wedges 3a, 3b. A first group of wedges 3a is formed of substantially parallelepipedal wedges having a flat face intended to be applied to the external cylindrical surface of the piece of ammunition. These first wedges 3a are arranged so as to extend along generatrices of the body of the piece of ammunition 200 and are intended, when locked in the engaged position, to wedge the piece of ammunition 200 radially, ideally aligning the axis of the piece of ammunition with the longitudinal axis X of the cradle as in Figure 2. The skilled person may choose to position axially the contact zones Z between the piece of ammunition and the wedges 3a, depending on the local mass of the different parts of the piece of ammunition. A second group of wedges 3b is located towards the rear AR of the cradle 2. Each of these second wedges 3b comprises a tooth profile 12 which is intended to cooperate with a groove 201 of the piece of ammunition 200 to ensure axial immobilization of the latter. In this way, when the wedges 3b of this second group are locked in the engaged position, the piece of ammunition 200 is axially wedged. Each wedge 3 is returned by default to the engaged position by the elastic means 4 such as leaf springs. Here, there is one spring leaf 4 per wedge 3, one end of which is inserted into the wedge in question. As can be seen in Figures 3 and 4, each spring leaf 4 thus allows a wedge 3a or 3b to be translated radially inwards the cradle 2, and through the corresponding openings 11. Thus, as can be seen in Figure 4, when a piece of ammunition 200 is introduced into the cradle 2 (in the direction of the axial arrow shown), the wedges 3 are pushed into a disengaged position (spread outwards from the cradle 2) by the passage of the piece of ammunition 200 which slides inside the cradle 2.

To facilitate the spreading of the wedges 3 by the piece of

ammunition, end chamfers 13 are provided on the wedges' ends

that are directed towards the front AV of the conveyor.

Once the piece of ammunition has been placed in the cradle

2 as shown in Figure 3, the wedges 3a and 3b, pushed by their

leaf springs 4, take up their engaged position. Each wedge 3a,

3b is then locked in this engaged position by the action of a

cam 8 secured to the conveyor.

To that end, each wedge 3 has at its base at least one

inclined plane 5 that is inclined relative to the direction of

translation of the wedge 3. This inclined plane 5 is intended

to cooperate in a form-fit with an inclined surface 6 carried

by one end of a cam 8.

The inclined planes and surfaces are arranged in such a

way that an axial translation of the cam 8, parallel to the

longitudinal axis X of the cradle 2 and towards the inclined

plane 5 of the corresponding wedge 8, has the effect of causing

a radial translation of the wedge 3 towards its engaged

position, thus ensuring a locking of the wedges 3a and 3b in

this engaged position.

The wedges 3 and the cams 8 thus radially and axially block

the piece of ammunition 200.

Advantageously, the parallelepipedal wedges 3 of the first

group 3a of wedges will each comprise two inclined planes 5,

each inclined plane being arranged at one of the longitudinal

ends of the wedge 3. Such an arrangement makes it possible to

avoid rotation of the wedge 3 and therefore ensures radial

translation of the wedges 3 with their flat faces remaining

parallel to the longitudinal axis X of the cradle and therefore

to the axis of the piece of ammunition.

The simultaneous translation of all the cams 8 is ensured

by rods 9 connecting the cams 8 to an actuator 10 capable of pushing or pulling the rods 9, such as an electric jack 10.

The cams 8 and actuator 10 are secured to the conveyor 104.

The rods 9 are translated so that the inclined surfaces 6

of the cams 8 push on the inclined planes 5 of the wedges 3

until these surfaces slide and cause the wedges 3 to translate

radially towards the interior of the cradle 2, thereby pressing

on portions Z of the external surface of the piece of

ammunition 200 to wedge it. The wedges 3 are thus wedged

between the piece of ammunition 200 and the cams 8.

When the conveyor 104 is aligned with the weapon and the

weapon is to be loaded, a pusher (pusher not shown) as

described in patent DE3328208 and which is preferably secured

to the conveyor 104, presses on the rear face of the piece of

ammunition 200, which has the effect of first advancing the

cradle 2 relative to the conveyor 104 visible in Figures 1 and

2.

In doing so, the cams 8 remain fixed relative to the

conveyor 104 while the wedges 3 move forward with the cradle.

The wedges 3 are then no longer wedged and the sole

pressure they exert on the piece of ammunition 200 is that

provided by the return springs 4. This force is however

sufficient to keep the piece of ammunition centred relative to

the cradle 2, which favours a correct introduction of the piece

of ammunition into the weapon. When the cradle 2 has run the

distance D shown in Figure 1, the piece of ammunition 200 is

pushed into the weapon by the pusher and moves the wedges 3

apart, which are no longer blocked by the cams 8.

It should be noted that the invention thus makes it

possible to radially and axially block a piece of ammunition

in its conveyor, which makes it possible to secure the

operations of loading and transporting a piece of ammunition

in a conveyor.

Claims

1- An ammunition conveyor comprising a cradle (2)

intended to contain a piece of ammunition (200), the conveyor

(104) being characterized in that it comprises wedges (3)

evenly distributed angularly around a longitudinal axis (X) of

the cradle (2), said wedges (3) being able to slide radially,

through openings, between a position engaged in the cradle (2)

and a position disengaged from the cradle (2) by the

introduction of a piece of ammunition which pushes the wedges

and against the action of at least one elastic means (4)

bringing the wedges (3) back into the engaged position, each

wedge (3) being lockable in the engaged position by the action

of at least one cam (8) secured to the conveyor (104) and

having an inclined surface (6) cooperating with at least one

inclined plane (5) carried by the wedge (8), the inclined

surfaces (6) and inclined planes (5) being arranged so that an

axial translation of the cam (8), controlled by an actuator

(10), causes a radial translation of the wedge (3), each wedge

(3) then being wedged between the cam (8) and the piece of

ammunition (200) and ensuring the immobilization of the piece

of ammunition (200) relative to the cradle (2).

2- The ammunition conveyor according to claim 1,

characterized in that the cradle (2) can translate

longitudinally relative to the conveyor (104), the translation

of the cradle (2) allowing the wedges (3) to be moved away

from their cams (8) which are secured to the conveyor (104),

which unlocks the wedges (3) and allows the piece of ammunition

(200) to slide on the cradle (104).

3- The ammunition conveyor according to one of claims

1 to 2, characterized in that the cradle (2) comprises two

groups of wedges (3), a first group (3a) being formed of

substantially parallelepipedal wedges (3) comprising a flat

face which is applied to the external cylindrical surface of the piece of ammunition (200) and which ensure radial immobilization of the piece of ammunition (200), and a second group of wedges (3b) which each comprise a tooth profile (12) intended to cooperate with a groove (201) in the piece of ammunition (200) in order to ensure axial immobilization of the latter.

4- The ammunition conveyor according to claim 3,

characterized in that the parallelepipedal wedges (3) of the

first group (3a) of wedges each have two inclined planes (5),

each inclined plane being arranged at one longitudinal end of

the wedge (3).

5- A turret for military vehicle, comprising at least

one ammunition (200) magazine (102a, 102b) comprising a

plurality of parallel cells and an ammunition (200) conveyor

(104) according to one of the preceding claims, the turret (1)

being characterized in that the conveyor (104) is mounted so

as to be pivotable around an axis (103) and can be placed in

a first position coaxial with a cell of the magazine (102a,

102b) in order to collect a piece of ammunition (200) therefrom

and a second position coaxial with a tube of a weapon (101) of

the turret (1) in order to allow loading.

6- The turret according to claim 5, characterized in

that the magazine (102a, 102b) comprises an extraction means

(105) for pushing a piece of ammunition out of the cell and

into the cradle (2) when the latter is coaxial with the cell

of the magazine (102a, 102b) at which the extraction means

(105) is placed.

7- The turret according to any one of claims 5 or 6,

characterized in that the magazine (102a, 102b) is in the form

of a cylinder.

8- The turret according to claim 7, characterized in

that it comprises two cylinders (102a, 102b) arranged

symmetrically on either side of a vertical plane passing

through the axis of the weapon (101).

9- The turret according to any one of claims 5 to 8, characterized in that the extraction means (105) comprises a pusher chain (105). 10- The turret according to any one of claims 5 to 9, characterized in that the conveyor (104) comprises a pusher allowing, in its second position, the piece of ammunition (200) placed in the cradle (2) to be positioned in the tube of weapon (101), the pusher causing the translation of the cradle (2) along the conveyor (104) until it is positioned in the vicinity of the tube of the weapon (101), as well as the unlocking of the wedges (3).