EP0258531B1 - Projectile body provided with a rotating strap arranged on it - Google Patents

Description

The invention relates to a projectile body as defined in the preamble of the claim.

In the case of swirl-stabilized projectiles, the projectiles are provided with one or - for reasons of stress and deformation - also several guide bands arranged one behind the other to transmit the swirl. The diameter of the guide bands is such that they press into the trains as the bullet passes through the tube.

It is known per se to introduce circumferential grooves in the guide band which serve to receive the guide band material which shears off to the rear (cf., for example, US Pat. No. 3,910,194). The width of such grooves is usually not greater than 4 mm. The guide tapes can e.g. B. made of copper, soft iron or plastic.

In these known guide bands, the radial contact between the tube and the guide band takes place only via the annular webs between the grooves. This contact causes a radial pressure on the projectile casing 1 (guide band pressure).

Especially when using thin projectile casings, in which the ratio between the wall thickness of the projectile casing to the tube caliber is 0.05, the projectile is particularly sensitive to radial pressure, since large stresses on the material can occur at the points depending on the projectile geometry. This allows the shell to be are pressed inwards and the seal against the propellant gases usually guaranteed by the guide band is no longer guaranteed.

A solid core projectile is also known from DE-C 731 064, the relatively wide guide band of which has several sections for receiving the sheared material. The problem of the deflection of the casing due to the axial guide band pressure does not arise with this projectile.

The present invention is therefore based on the object of specifying a projectile body of the type mentioned in the introduction, in which, when using thin-walled casings, a better sealing against the gas pressure takes place.

This object is achieved by the features of the characterizing part of the patent claim.

The invention is therefore based on the idea of providing relief at the points in the region of the guide band where the bullet casing is subjected to high stress in the radial direction.

The axial extent of the relief grooves depends on the rigidity of the shell and should be> 4 mm for artillery shells with metal guide bands.

The invention is described in more detail below with the aid of an exemplary embodiment and with the aid of figures.

• Fig. 1 ein an sich bekanntes Geschoß mit erfindungsgemäßem Führungsband;
• Fig. 2 eine Detailansicht eines erfindungsgemäßen Führungsbandes, das auf der Geschoßhülle angeordnet ist; und
• Fig. 3 die Druckverteilung längs des Führungsbandes gemäß Fig. 2.

Show it:

• Figure 1 is a known projectile with a guide band according to the invention.
• Fig. 2 is a detailed view of a guide tape according to the invention, which is arranged on the projectile casing; and
• 3 shows the pressure distribution along the guide belt according to FIG. 2.

In Fig. 1, 1 denotes a projectile body, 2 the projectile casing and 3 the guide band. The guide band 3 is dimensioned so that it fully presses into the trains when the projectile passes through the tube. It transmits the swirl to the floor via the rail guide of the trains and at the same time seals against the powder gases. In the area of the guide band 3, the projectile 1 has a cavity 4 inside, in which, for. B. a brake parachute, not shown, can be accommodated.

In Fig. 2, 2 again designates the projectile shell on which the guide band 3 according to the invention is arranged. The grooves denoted by 31 to 34 serve in a known manner to accommodate the guide band material which also shears off at the rear when the projectile body passes through the tube.

The radial contact between the tube and the guide band 3 exists only at the guide band rings 36 to 41.

3 shows the example of a pressure distribution along the guide belt. The distance a in mm from the leading edge of the guide belt is plotted on the abscissa and the guide band pressure P in bar is plotted on the ordinate. The dashed curve 300 shows the guide band pressure distribution for a guide band without grooves according to the storey structure with cavity 4 shown in FIG. 1. It can clearly be seen that a maximum guide band pressure occurs approximately in the middle of the guide band.

Accordingly, a relief groove must be provided in this area. This groove was designated 35 in FIG. Their width B should be wider than 4 mm.

For artillery shells, the width B should be between 6 and 20 mm, depending on the type of the projectile. However, it should be taken into account that the total width of the guide band rings in such projectiles should be approximately 20 mm (typically, guide bands have a width of 38-40 mm).

The step curve 301 in FIG. 3 gives approximately the pressure distribution of the guide belt 3 according to FIG. Fig. 2 again. Due to the relief groove 35, the guide band pressure drops significantly in this area.

Of course, depending on the determined guide band pressure distribution, several relief grooves can also be provided.

Claims (3)

1. Projectile body (1) of which the projectile casing

(2) bears a guide band (3) which, in order to receive the guide band material displaced rearwardly when the projectile body (1) passes through the barrel, is provided with grooves (31, 32, 33, 34) characterised by the fact that in those zones of the guide band (3) in which maximum stress occurs in the radial direction there is at least one groove (35) which is wider than the remaining grooves (31, 32, 33, 34) provided for receiving the displaced material, the distance occupied by the relieving groove (35) depending on the rigidity of the projectile casing (2).

2. Projectile body (1) in accordance with Claim 1, characterised by the fact that the pressure relieving groove (35) has a width B of over 4 mm.

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