ES2952704T3 - Projectile - Google Patents

Abstract

A support unit (12) for a projectile (2) of a guided ammunition, two parts of the projectile (8a, b) being joined with the help of the support unit (12) and which are displaceable and rotatable relative to each other, contains a Bearing bearing (18) with a first and second ring (20a, b) and rolling elements (22), the first ring (20a) being fixed to a first mounting section (28a) of the first projectile part (8a) in the axial direction of a longitudinal axis (4) and the second ring (20b) in a second mounting section (28b) of the second projectile part (8b) is displaceably mounted in the axial direction, and a spring element ( 46), which in a tube position (R) deflects the second ring (20b) in the axial direction with respect to the second projectile part (8b) and the projectile (2) after being fired, is transferred from the barrel position (R) to flight position (F). A projectile (2) contains the first (8a) and second projectile parts (8b) and the storage unit (12). (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

Projectile

The invention relates to a steerable ammunition projectile.

A projectile of a driving ammunition known in practice contains two parts of the projectile, that is, the effective projectile casing and a rear stabilizer rotatably housed about the central longitudinal axis of the projectile and thus decoupled in rolling.

The slewing bearing is carried out by a bearing unit containing roller bearings.

Due to the self-weight of the roller bearings and the high acceleration (when launching the projectile from a tube), brinelling occurs on the rolling surfaces of the bearing. These reduce rolling behavior and cause undesirable effects. It is necessary to avoid this.

From JP 2010-78221 A it is known to provide a missile with a steering wing that sufficiently supports the acceleration force during firing and improves controllability in the direction of propulsion.

From document WO 02/06761 A1, a fin-stabilized missile is known, with a bearing between the fuselage part and the rear part, the bearing being constructed with special load-bearing contact surfaces, which limit the loads during anchoring and firing. and during the flight of the missile through the air.

It is the task of the invention to propose improvements in such a bearing unit, or in such a projectile.

The object of the invention is solved by a projectile according to claim

1. Preferred or advantageous embodiments of the invention, as well as other categories of the invention, result from the additional claims, from the following description, as well as from the accompanying figures.

The bearing unit is such a unit for a projectile of a driving ammunition. In this case, the following projectile is started: along a longitudinal axis (central longitudinal axis), the projectile contains a first projectile part and a second projectile part. The projectile may also contain other projectile parts. The first part of the projectile is, for example, an effective projectile body/shell. The second part of the projectile is, for example, a rotating body that can rotate in front of the projectile body, for example a structure or a rear or front stabilizer, in particular with stabilizing elements, such as canards. Alternatively, also the first part of the projectile may be the stabilizer and the second part of the projectile may be the projectile casing, etc.

Both parts of the projectile are joined (to or on their respective mounting section, see below) with the help of the bearing unit as follows: With the help of the bearing unit, i.e. the mounting, both parts of the projectile are displaceable in the axial direction (in this case, "directions" always refer to the longitudinal axis) between a tubular position and a flight position. In the tubular position, both parts of the projectile rest in the axial direction and in the flight position they are spaced apart. Therefore, the projectile parts can be separated, in particular they can also move relative to each other. Thanks to the assembly, both parts of the projectile are also rotatable around the longitudinal axis in the flight position with the help of the bearing unit. Therefore, the tubular position forms a first final state in which the projectile is grouped and the projectile parts abut each other. In the flight position, the parts of the projectile are separated from each other, therefore they have a distance, or play, so that they are rotatable with respect to each other.

The bearing unit contains a roller bearing - in particular an axially guided one - with a first and a second ring and rolling bodies, possibly with a cage for the rolling bodies, etc. "Axially guided" means that its first and second rings (inner ring and outer ring or vice versa) are not displaceable relative to each other in the axial direction. Therefore, the bearing can accept axial forces in both directions. Therefore, a displacement between the rings is not possible in the axial direction, for example such a bearing is constructed as one or more grooved ball bearings or as two shoulder ball bearings in an O- or X-shaped arrangement, or contains these. . The "ring" then degenerates, if necessary, into two or more individual rings.

The bearing unit contains a first section for mounting the first part of the projectile and a second section for mounting the second part of the projectile. In this case, the mounting sections are the necessary parts of the projectile that serve for assembly, or the accommodation of the remaining elements of the bearing unit (roller bearing, spring element, see below), causing these parts remaining, among others, the true assembly.

The first ring is fixed in the axial direction on the first mounting section. The second ring is movably mounted in the axial direction on the second mounting section. In this case, "fixed" means a stationary arrangement with respect to the axial direction. "Displaceably mounted" means mobility in the axial direction. A movement in the circumferential direction may be possible for both rings, but in particular a stationary arrangement is also provided in this case. A rotation between the projectile parts, or the mounting sections, is then only possible by means of roller bearings. The rings are always fixed in the radial direction.

The bearing unit contains a spring element which, in the tubular position, prestresses the second ring in the axial direction in a launching direction against the second part of the projectile with a prestressing force. Furthermore, the spring element is configured to move from the tubular position to the flight position, that is, to separate both parts of the projectile in the axial direction. This is considered only in the case where such movement is possible, for example upon release of a retaining element (see below) or after the launch of the projectile, if external forces allow it (e.g. sufficiently decreasing acceleration after launch). .

The invention is based on the following knowledge, observations, or considerations, and also presents the following embodiments. In this case, the embodiments are also called "the invention" in part in a simplified manner. In this regard, the embodiments may also contain parts or combinations of the above-mentioned embodiments or correspond to them and/or if necessary also include embodiments not mentioned so far.

After passage through the tube and, therefore, after the launch discharge, free rotation must be possible between both parts of the projectile, in particular the rear stabilizer, around the longitudinal axis of the projectile. Therefore, as roller bearings, bearings are chosen that guarantee friction-free and constant rotation around the axis of rotation (longitudinal axis) during the flight phase. When selecting the respective bearings, it must be ensured that they withstand the acceleration forces during launch and do not deteriorate, since, otherwise, unlimited function is not guaranteed. Very high friction moments would have the consequence that the turning movements of the rear stabilizer would be coupled again to the front area of the projectile. In this case, the friction moments that occur cannot be considered constant parameters, which would greatly complicate and negatively influence canard control in particular.

To avoid deterioration of the bearings through high launch loads, the acting forces must be dissipated through the rear structure (e.g. the second part of the projectile) into the projectile (e.g. the first part of the projectile). , so that the bearings are loaded only by their own weight. This is achieved through the tubular position and the support of both parts of the projectile against each other. Therefore, after leaving the tube a bearing groove must be released by a displacement of the rear structure (separation of the projectile parts for the flight position). This is achieved by the spring element. The bearings are loaded both radially and axially.

In addition, the long storage time of the ammunition (several years) and the associated long downtime of the installed bearing, which may thus contain, for example, maintenance-free lubrication, must be considered to meet these requirements.

The bearing unit is housed in particular inside the shell of the projectile and is therefore protected against deformation (e.g. crushing during launch). The assembly consists in particular of two tensioned spindle bearings in an O-shaped arrangement, in particular angular contact ball bearings with ceramic balls and a pressure angle of 25°. This arrangement generates slight prestressing and high rigidity of the bearing unit. The prestressing of the bearings (inner rings, mounted in a part of the projectile, for example in a spiral stabilizer) adopts in particular a sliding seat together with an adjusting nut. In the outer rings, the bearings are fixed to another part of the projectile (for example the projectile body support for the spiral stabilizer) in particular with the help of an external adjusting nut. In particular, this external adjusting nut simultaneously adopts the guide of the spring element, especially of disc springs.

Due to the tensioning of the bearings, high axial static forces act on the front bearing (seen in the direction of flight) during launch, since both inner rings, balls and cages, as well as the sliding seat and the adjusting nut must withstand acceleration.

A force of, for example, 7439.9 N is generated by the acceleration and the masses of the components. The problem is that the bearing can withstand a maximum Hertz compression of 4200 Mpa and with it a maximum force of 4500 N.

Since the bearing would deteriorate and brinelling would occur due to the force, according to the invention, the load is reduced by the construction. For this purpose, the spring element, in particular disc springs, is provided, which provides a force of 3065 N in the prestressed state against the launching load.

By means of this measure, the load on the bearing can be limited, for example tolerably to 7439.9 - 3065 = 4374.9 N. To generate the necessary spring travel (axial movement from the tubular position to the flight), for example 2 mm, to release the assembly, in particular several, for example five disc springs are stacked in a column of disc springs. However, since each individual disc spring generates a force of 1177.2 N due to its own weight and high acceleration, a support element is provided. This component ("support / support element") is incorporated into the disc spring column. In this way, the force required to avoid overloading the bearing can be maintained.

Through the slot produced by the axial movement between tubular and flight position, for example of approximately 0.28 mm, one of the projectile parts (for example the rear structure with the fins) can rotate freely around the other part of the projectile (for example the shell of the projectile), which guarantees, for example, the function of the rear stabilizer decoupled in rolling. The slot is held open in particular by the remaining force of the spring element (for example disc springs, for example with about 300 N) in the flight position.

Therefore, according to the invention, a firm mounting on acceleration occurs. It results in a bearing unit for a driving ammunition that does not receive any damage, even under high accelerations of a barreled weapon.

A force is provided by the spring element (especially disc springs) that acts against the force produced during the release. This reduces deterioration of the bearing unit due to the high axial static load at launch. According to the invention, only a few components are necessary, which enables a compact form of construction.

By supporting the second ring according to the invention - via an additional support ring ("support element") - the construction can be structured from a few simple components as well as a pair of standardized parts.

In a preferred embodiment, the spring element is a spring pack consisting of individual springs stacked in the axial direction. The individual springs are special disc springs. In this way a suitable spring element can be realized particularly conveniently.

According to the invention, the spring package contains a first and a second package part in the axial direction. The first part of the package faces the second ring, the second part of the package faces the second mounting section. Both parts of the package are decoupled in the tubular position via a support element. For this purpose, the support element rests against the throwing direction on a stop on either the second mounting section and thus absorbs the force of the first part of the package or the second ring. Consequently, the second part of the package is decoupled with respect to its own mass, or acceleration, with respect to the support of the second ring. However, the parts of the package are coupled in the flight position. This is achieved by the support element being lifted (by means of the spring force / spring travel of the second part of the package) from the stop in the direction of flight and being movable in the axial direction. In this way, a large spring travel can be achieved to take the projectile from the tubular position to the flight position.

In a preferred embodiment, on the first mounting section the first ring is fixed in the axial direction and in the circumferential direction, and on the second mounting section the second ring is mounted displaceably in the axial direction and fixed in the circumferential direction. This corresponds to the fixing of rings in the circumferential direction mentioned above, whereby the rotation between the parts of the projectile is achieved only by the roller bearing, or the rolling bodies, which leads to a particularly defined rotation.

In a preferred embodiment, the bearing unit is formed to support the projectile therein after reaching the flight position. An additional component, for example for locking the projectile in the flight position, is therefore avoided. Therefore, the bearing unit has multiple functionality.

In a preferred variant of this embodiment, the bearing unit is formed for retaining the projectile in the flight position by the spring element pre-tensioning the second ring in the axial direction in the direction of launching the projectile against the second part of the projectile in the flight position with a holding force. The holding force is especially smaller than the prestressing force. In this way, by means of a corresponding spring element (sufficiently strong, sufficient spring travel, ...) a particularly simple retention in the flight position can be achieved.

In a preferred embodiment, the bearing unit contains a sliding element. Thus, the second ring is displaceably mounted on the second mounting section in the axial direction with the second ring being fixed to the sliding element in the axial direction and the sliding element being displaceably mounted on the second mounting section in the axial direction. . Accordingly, in particular, several partial bearings (see below) can be grouped together to form the roller bearing and their second rings can be fixed together on the sliding element so that these can be moved together relative to the second mounting section.

In a preferred embodiment, the roller bearing contains at least two partial bearings. In this case, each sub-bearing is again a roller bearing and contains a first and a second ring and rolling bodies, possibly a cage for the rolling bodies, etc. For example, in this way, the bearings mentioned above can be combined in an O-shaped or X-shaped arrangement to give a common roller bearing. In this way a particularly convenient mounting on the projectile can be realized.

In a preferred variant of this embodiment, two of the partial bearings are shoulder ball bearings in an O-shaped arrangement. This leads to a particularly suitable mounting for a projectile.

In a preferred variant of this embodiment, the first rings of the partial bearings are fixed together on the first mounting section. Alternatively or additionally - in combination with the aforementioned sliding element - the second rings of the partial bearing are fixed together on the sliding element in the axial direction. This leads to a particularly simple fixing possibility of the rings on both mounting sections.

However, it is not strictly necessary that the bearing be made up of two partial bearings. Bearings are also available in two fixed in one housing. On the other hand, other types of bearings, such as moment-of-force bearings or grooved ball bearings, are also conceivable for construction. Therefore, the above-described arrangement of two shoulder ball bearings or angular contact ball bearings in an O-shaped arrangement represents one of several possible arrangements.

The object of the invention is also solved by a projectile according to claim 11, with the first and the second part of the projectile and the bearing unit according to the invention. The projectile and at least some of its embodiments, as well as the respective advantages, have already been explained analogously in relation to the bearing unit according to the invention.

In a preferred embodiment, the first part of the projectile is a projectile body, especially a projectile casing, and the second part of the projectile is a rotating body, especially a front/rear structure, a front/rear stabilizer , especially with canards, especially a spiral stabilizer.

In another preferred embodiment, the first and second parts of the projectile are formed in the adjacent area as a pair of conical shapes that fit at least partially in a positive connection in the tubular position. By means of the taper a particularly convenient projectile can be created.

In a preferred variant of this embodiment, the first projectile part has a cone shape that tapers against the direction of launch and the first projectile part rests on the second projectile part both on the blunt front surface and also on the lateral surface. The cone is a right circular cone. Such a form can be realized in a particularly simple manner.

In a preferred embodiment, the first and second projectile parts are supported in the tubular position by a retaining member, the retaining member being configured to release upon launch and release the projectile parts for movement in the position. Of flight. In this way, the projectile is supported in the tubular position already before launch. The retaining element is, in particular, a retaining bolt with a controlled axial action starting point, which is removed by the exit of the projectile tube.

Other characteristics, effects and advantages of the invention result from the following description of a preferred embodiment of the invention, as well as from the accompanying figures. In this case they show, each in a schematic principle sketch:

Figure 1, a projectile with a bearing unit in a tubular position,

Figure 2, the bearing unit as detail II of Figure 1,

Figure 3, the projectile of Figures 1 and 2 in flight position.

Figures 1 to 3 show a steerable projectile 2, or a projectile of a steerable ammunition not further shown. In this case, Figure 2 shows detail II of Figure 1. Figures 1 and 2 show a tubular position, Figure 3 shows a flight position of the projectile 2. The projectile 2 has a longitudinal axis 4, or a central longitudinal axis and a launching direction 6. In the launching direction 6, in its use the projectile 2 is fired from a protection tube not shown.

The projectile 2 contains a first projectile part 8a in the form of a front projectile body, or a projectile casing, and a second projectile part 8b in the form of a rotating body, or rear stabilizer, in this case a spiral stabilizer. The rear stabilizer features 10 controllable fin-shaped wings, either canards, which are folded or in a state of rest in Figures 1 and 2; In Figure 3, these are deployed and used for the direction of projectile 2.

The projectile 2 contains a bearing unit 12. By means of this, both projectile parts 8a,b are joined, either fixed to each other, or supported in the following way: the projectile parts 8a,b are movable relative to each other in an axial direction along the longitudinal axis 4. In this way, they can be moved axially or separated from each other from a first final position, the tubular position R according to Figures 1 and 2, to a second final position. , the flight position F according to Figure 3 (arrow 14). In the flight position F according to Figure 3, these can also rotate relative to each other around the longitudinal axis 4 (arrow 16 around the longitudinal axis 4).

The bearing unit 12 contains a roller bearing 18 with a first ring 20a, in this case an outer ring, and a second ring 20b, in this case an inner ring. The rolling bodies 22 of the bearing unit are balls here, which are guided in a cage of the bearing unit 12, not shown. In the example, the roller bearing 18 (one, common) is made up of two partial bearings 24a,b, here two shoulder, angular contact or spindle ball bearings, which are tensioned in an O-shaped arrangement. Each of the partial bearings 24a,b respectively has a first ring 26a and a second ring 26b, as well as a part of the rolling bodies 22 and its own guide cage for these.

Also attached to the bearing unit 12 is a respective first mounting section 28a of the first projectile part 8a and a second mounting section 28b of the second projectile part 8b. The mounting sections 28a,b serve to fix or accommodate the other components of the bearing unit 12 - among others the roller bearing 18 - in the projectile parts 8a,b.

The first ring 20a is fixed on the first mounting section 28a in axial, radial and circumferential directions. For this purpose, both first rings 26a are tensioned in the axial direction via an external adjusting nut 30 against a stop shoulder 32 of the first projectile part 8a.

The second ring 20b is movably mounted in the axial direction and fixed in the radial direction on the second mounting section 28b. For this purpose, both second rings 26b are fixed to a movable element 34, which is itself movable in the axial direction with respect to the second mounting section 28b. The sliding element consists of a sliding seat 36 and an adjusting nut 38, the second rings 26b being tensioned in the axial direction on the sliding seat 36, or its stop shoulder 40, through the adjusting nut 38. adjusting nut 42, as well as a stop 44 in the form of a shoulder (see below), limit the displaceability of the sliding element 34 and with it of the ring 20b.

The bearing unit 12 contains a spring element 46, here a spring package consisting of two parts of the package 48a,b, containing in total five individual springs 50, here disc springs. The first part of the package 48a contains one, the second part of the package 48b contains four individual springs 50. Both parts of the package 48a,b are uncoupled in the tubular position R via a support element 52. The support element 52 is here an annular disc, which is displaceable in the axial direction on the second mounting section 28b, but rests on the stop 44 against the launching direction 6 in position R, which ensures the decoupling mentioned above.

The outer adjustment nut 30 also serves to house or guide the spring element 46, including the support element 52.

In the tubular position R, the spring element 46 tensions the second ring 20b as well as the sliding element 34 in the launching direction 6 against the second projectile part 8b with a pretensioning force FV of 3065N.

The first and second parts of the projectile 8a,b are formed in the adjacent area (during the tubular position R) as a pair of conical shapes that at least partially fit positively in the tubular position R. The first part The projectile 8a has a cone shape that tapers against the launching direction 6 and rests on the second part of the projectile 8b both on the blunt front surface 54 and also on the side surface 56.

The first and second projectile parts 8a,b are supported in the tubular position R by a retaining element 58. The retaining element 58 is here a pin screwed into the first projectile part 8a in the first mounting section 28a, which rests on the second part of the projectile 8b, or mounting section 28b, through a protective cover 60. The protective cover 60 also serves to keep the wings 10 in a folded state when firing the projectile 2 even during the passage through the tube.

Therefore, in the tubular position R, a groove S1 occurs between sliding seat 36 and 2 mm adjusting nut 42, as well as a zero groove S2 between projectile parts 8a and 8b, in particular between front surface 54 and surface opposite on the projectile part 8b and a zero slot S3 between lateral surface 56 and opposite surface on the projectile part 8b.

During launch, projectile 2 is greatly accelerated. Due to the zero grooves S2,3, the projectile parts 8a,b fit positively and their inertial masses do not act on the bearing unit 12. However, due to inertia the force flow of the inertial force FT of 7439.9N to the components sliding seat 36, adjusting nut 38, inner rings in the form of the second rings 26b and rolling bodies 22 (including undrawn cages) plotted in Fig. 2. This inertial force inertia FT must be absorbed only by the rolling bodies 22 in the upper part of Fig 2, either its rolling area in the upper outer ring, or the first upper ring 26a, which is indicated by the oblique arrow shown in Figure 2.

Thanks to the prestressing force FV, which opposes the inertia force FT, the load of the "upper" rolling bodies 22 in the figures, or of the ring 26a, is thus reduced to FT - FV = 7439, 9N - 3065N = 4374.9N. The retaining element 58 is configured to release after a launch and release the projectile parts 8a,b for movement in the flight position F. Upon leaving the tube, the retaining element 58 is torn off for this purpose at a point of controlled start 62, and the protective cap 60 is removed from the projectile 2. Only a remainder of the retaining element 58 remains in the projectile part 8a. The wings 10 open in the deployed position shown in Fig. 3.

After launching, or when the retaining element 58 is torn off, the spring element 46 serves to move both parts of the projectile 8a,b away in the axial direction and thus move from the tubular position R (Figures 1, 2) to the flight position F (Figure 3).

The retaining element 46 expands in the axial direction. In this context, the support element 52 is lifted from the stop 44, which leads to only the partial packages 48a,b being coupled with respect to the total spring package, or to the spring element 46. The spring element 46 causes a holding force FH of approximately 300N on the second ring 20b after reaching the flight position F. Accordingly, the bearing unit 12 is configured to support the projectile 2 therein after reaching the flight position F.

The slot S1 is now widened to zero, the slot S2 to 2 mm and the slot S3 to 0.2783 mm, which results in a free rotation of the projectile parts 8a,b around the longitudinal axis 4, which is carried out only through the rolling of the rolling bodies 22 in the roller bearing 18.

List of reference symbols

2 Projectile

4 Longitudinal axis

6 Launch direction

8a,b Part of the projectile

10 Wing

12 Bearing unit

14 arrow

16 Arrow

18 Roller bearing

20a,b Ring

22 Rolling body

24a,b Partial bearing

26a,b Ring (partial bearing)

28a,b Assembly section

30 External adjustment nut

32 Stop shoulder

34 Sliding element

36 Sliding seat

38 Adjustment nut

40 Butt shoulder

42 Stop nut

44 Stop

46 Spring element

48a,b Part of the package

50 Single spring

52 Support element

54 Front surface

56 Side surface

58 Retaining element

60 Protection cap

62 Controlled breaking point

R Tubular position

F Flight position

FV Prestressing force

FH Holding force

FT Force of inertia

S1-3 Slot

Claims (12)

1. Projectile of an orientable ammunition with a bearing unit (12), the projectile (2) containing along a longitudinal axis (4) a first part of the projectile (8a) and a second part of the projectile (8b), being both parts of the projectile (8a,b) are joined with the help of the bearing unit (12) and these are movable relative to each other in an axial direction between a tubular position (R) and a flight position (F), supporting each other on the tubular position (R) both parts of the projectile (8a,b) in the axial direction and these being distanced from each other in the flight position (F), both parts of the projectile (8a,b) being able to rotate around the longitudinal axis (4) with respect to each other in the flight position (F) with the help of the bearing unit (12), - with a roller bearing (18) with a first and a second ring (20a,b) and rolling bodies (22), - with a first mounting section (28a) of the first part of the projectile (8a) and a second mounting section (28b) of the second part of the projectile (8b), - the first ring (20a) being fixed in the axial direction on the first mounting section (28a) and the second ring (20b) being mounted displaceably in the axial direction on the second mounting section (28b), - with an element spring (46), which pretensions in the tubular position (R) the second ring (20b) in the axial direction in a launching direction (6) of the projectile (2) in front of the second part of the projectile (8b) with a force prestressing (FV), - the spring element (46) being configured to move the projectile (2) after its launch from the tubular position (R) to the flight position (F), - the spring package containing in the axial direction a first (48a) and a second part of the package (48b), the first part of the package (48a) being oriented towards the second ring (20b) and the second part of the package (48b) being ) oriented towards the second mounting section (28b), and both parts of the package (48a,b) being uncoupled in the tubular position (R) by a support element (52) that rests on a stop (44) against the direction of launch (6) and the parts of the package (48a,b) being coupled in the flight position (F) by means of the support element (52) raised from the stop (44) and mobile in the axial direction. 2. Projectile (12) according to claim 1, characterized because the spring element (46) is a spring package stacked in the axial direction constituted by individual springs (50). 3. Projectile (12) according to one of the preceding claims, characterized because the first ring (20a) is fixed in the axial direction and the circumferential direction on the first mounting section (28a) and the second ring (20b) is movably mounted in the axial direction and fixed in the circumferential direction on the second section assembly (28b). 4. Projectile (12) according to one of the preceding claims, characterized because the bearing unit (12) is formed to support the projectile (2) therein after reaching the flight position (F). 5. Projectile (12) according to claim 4, characterized because the bearing unit (12) is formed to support the projectile (2) in the flight position (F) by prestressing the spring element (46) the second ring (20b) in the axial direction in the launching direction (6 ) of the projectile (2) against the second part of the projectile (8b) in the flight position (F) with a holding force (FH). 6. Projectile (12) according to one of the preceding claims, characterized because the bearing unit (12) contains a sliding element (34) and the second ring (20b) is mounted displaceably in an axial direction on the second mounting section (28b) with the second ring (20b) being fixed on the sliding element (34) in the axial direction and the sliding element (34) being mounted displaceably in the axial direction on the second mounting section (28b). 7. Projectile (12) according to one of the preceding claims, characterized because the roller bearing (18) contains at least two partial bearings (24a,b). 8. Projectile (12) according to claim 7, characterized because two of the partial bearings (24a,b) are in an O-shaped arrangement in the shoulder ball bearing. 9. Projectile (12) according to one of claims 7 to 8, characterized wherein the first rings (26a) of the partial bearings (24a,b) are fixed together on a first mounting section (28a) and/or - in combination with claim 6 - the second rings (26b) of the partial bearing (24a,b) are fixed together on the sliding element (34) in the axial direction. 10. Projectile (2) according to one of the previous claims, characterized because the first (8a) and the second part of the projectile (8b) in the adjacent area is formed as a pair of conical shapes that adapts at least partially in positive union in the tubular position (R). 11. Projectile (2) according to claim 10, characterized because the first part of the projectile (8a) has a cone shape that tapers against the direction of launch (6) and rests both on the blunt front surface (54) and also on the lateral surface (56) on the second part of the projectile (8b). 12. Projectile (2) according to one of claims 10 to 11, characterized because the first (8a) and the second part of the projectile (8b) are supported by a retaining element (58) in position (R), the retaining element (58) being configured to release after a launch and release the parts of the projectile (8a,b) for movement in the flight position (F).