Sealing band for projectile, sub-caliber projectile and ammunition equipped with such a band
View Patent ↗Sealing band for a projectile, the band being characterized in that it comprises a front sub-band containing at least two sectors, the sub-band having at least a conical profile in a tight fit with the matching profile of a groove of the projectile, the cone tip being placed towards a rear section of the projectile, with the sub-band attached to the projectile by a cylindrical skirt.
1. A sealing band for a projectile, the band comprising:
a front sub-band comprising at least two axially longitudinal sections, the sub-band having at least one conical section, which in an axial cross-section includes a wedge-shaped profile, for tightly fitting with an adjacent bottom surface of an annular groove of such a projectile, said groove having a matching complementary wedge-shaped profile, and
a cylindrical skirt removably attached to and fully covering the circumferential exterior surface of the sub-band,
wherein the sub-band is not rotatable with respect to such projectile around a longitudinal axis of such projectile.
2. A sealing band according to claim 1 , wherein the skirt has on its internal surface means for fastening to the sub-band.
3. Sealing band according to claim 2 , characterised in that the skirt has an internal circular collar for the sub-band.
4. A sealing band according to claim 1 , further comprising a layer of sealing material at the rear of the sub-band relative to a front end of such projectile.
5. A sealing band according to claim 1 , wherein the skirt has a diameter, and a length between 50% and 80% of its diameter.
6. A sealing band according to claim 1 , wherein each sub-band section comprises at least one indentation for connecting to a corresponding indentation of a neighbouring section for forming a sealing deflecting plate for propellant gases, such that at least part of each indentation passes through a single line parallel to a central axis of the sealing band.
7. A sealing band according to claim 6 , further comprising a flexible sealing material between said sub-band sections and at a rear section of the sub-band.
8. The sealing band according to claim 6 , wherein the sub-band sections are arc-shaped and the deflecting plate is circular.
9. A sealing band according to claim 1 , wherein a rear section of the skirt of the band has a diameter greater than a calibre of a barrel for firing such projectile.
10. A sealing band according to claim 1 , wherein a front section has a diameter smaller than a calibre of a barrel for firing such projectile.
11. A projectile comprising a sub-calibre core held by a full-calibre sabot comprising at least two segments, said projectile having a band according to claim 10 wherein the sabot further comprises a pusher plate located axially forward of a transversal plane passing through the center of gravity of the projectile, the pusher plate comprising at least one circumferential groove for receiving the sub-band.
12. A projectile according to claim 11 , characterised in that each segment from the sabot has a rear calibre guiding support.
13. A projectile according to claim 11 , characterised in that each segment of the sabot has a reinforcing rib extending longitudinally to the back of the pusher plate.
14. A projectile according to claim 13 , characterised in that the rib is in contact with the skirt of the band.
15. A projectile according to claim 14 , characterised in that the skirt of the band is provided with longitudinal internal grooves in which the ribs are fitted in.
16. Ammunition comprising a casing enclosing a propellant charge and a projectile according to claim 10 , wherein the cylindrical skirt is attached to a fastening ring fixed at the casing.
17. Ammunition according to claim 16 , characterised in that part of the propellant charge is placed in the skirt of the band.
18. The sealing band according to claim 1 , wherein the at least two sections of the sub-band are arc-shaped.