Improvements to sub-combat units

Abstract: The invention relates to a sub-combat unit which is arranged to be separated from a flying body, for example a carrier shell or the like, for example over a target area, the sub-combat unit including a warhead, a target detector and two diametrically disposed carrier surfaces (1, 2) which, via carrier arms (7, 8) are pivotally disposed each on its own shaft (4, 5) located in a plane which is normal to the line of symmetry of the warhead from a collapsed position in which the carrier arms and carrier surfaces connect to the circumferential surface of the sub-combat unit, and to a position opened at 90° at which both of the carrier surfaces form a retarding area for the fall velocity of the sub-combat unit and impart to the sub-combat unit a rotation for scanning the target area in a helical pattern during the fall of the sub-combat unit towards the target area. The sub-combat unit includes a wing flip-out mechanism with damping devices (9, 10) of rubber disposed on each carrier surface (1, 2), in connection with the casing of the sub-combat unit, the damping devices being compressed by the carrier arms (7, 8) during the flip-out movement, and return stops (11, 12) against which the carrier arms are operative to spring back.

Description: TECHNICAL FIELD The present invention relates to a sub-combat unit which is arranged to be separated from a flying body, for example a carrier shell or the like, over a target area, the sub-combat unit including a warhead, a target detector and two diametrically disposed carrier surfaces which, via carrier arms, are pivotally disposed each on its own shaft located in a plane which is normal to the line of symmetry of the warhead from a collapsed position in which the carrier surfaces connect to the circumferential surface of the sub-combat unit and to a position opened at 90° at which both of the carrier surfaces form a retarding area for retarding the velocity of the sub-combat unit and imparting to the sub-combat unit a rotation for scanning the target area in a helical pattern during the fall of the sub-combat unit towards the target area. The unit further includes damping devices and return stops disposed adjacent to each carrier surface in connection with the casing of the sub-combat unit. The damping devices are compressed by the carrier arms on flip-out of the carrier surfaces and the return stops create a stop against which the carrier arms are operative to spring back. A sub-combat unit of this kind has been previously described in EP-A-0 424 337 on which disclosure the preamble of independent claim is based. BACKGROUND ART Both of the carrier surfaces are relatively thin and may, for example, be of titanium. This material is elastically bendable so that the carrier surfaces, in their inwardly collapsed state, follow the circumferential surface of the sub-combat unit, but in their opened-out or flip-out position are bent out to a position at which they assume a certain shape. In their closed position, the carrier surfaces are locked to the circumferential surface of the sub-combat unit in a suitable manner. For example, the thin carrier surface profile may engage in a groove or slot in the circumferential surface. The carrier surfaces are twisted from their inwardly closed position with the aid of their inherent energy, the rotational and aerodynamic forces, through 90° to their flipped-out position. EP-A-0 424 337 proposes that a damping device be introduced such that the carrier surfaces are stopped gently in the flipped-out position, and any possible pendulum motion is prevented. OBJECTS OF THE INVENTION One object of the present invention is to realize a wing flip-out mechanism which permits a high flip-out speed of the carrier surfaces and gentle braking to a final, flipped-out position. Furthermore, the mechanism must be of simple and compact construction and it may not take up any appreciable space. SOLUTION According to the present invention, the end of the carrier arms which is journalled on the flip-out shafts includes an abutment surface which, in the collapsed position, abuts against the damping device and, in the flip-out position, against the return stop. The cooperation between a respective abutment surface and a return stop during the influence of a damping device will provide a gentle braking and restricted return movement to a final, well-defined flip-out position of the carrier surfaces. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS The present invention will now be described in greater detail hereinbelow, with particular reference to the accompanying Drawings which show one example of how the wing flip-out mechanism may be designed. In the accompanying Drawings: Fig. 1 shows the sub-combat unit with the carrier surfaces in the closed position; Fig. 2 shows the carrier surfaces in their flip-out position. DESCRIPTION OF ONE EMBODIMENT The sub-combat unit is arranged to be separated from a vehicle or carrier shell. The carrier shell may, for example, be of 15.5 cm calibre and be discharged from a field artillery gun in a conventional manner in a ballistic trajectory towards a target area. In order to impart to the sub-combat unit a controlled scanning movement of the target area, i.e. a controlled rotation and fall velocity, two diametric carrier surfaces 1 and 2 are pivotally disposed from an inwardly closed position in which the carrier surfaces connect to the casing surface 3 of the sub-combat unit, and to a flipped-out position in which the two carrier surfaces form a retarding area. Both of the carrier surfaces 1, 2 are pivotally disposed on flip-out shafts 4, 5 which are at right angles to the line of symmetry of the warhead. The warhead 6 may be of per se known type and will not, therefore, be described in greater detail here. The sub-combat unit according to the present invention includes a special wing flip-out mechanism which consists of the two carrier arms 7, 8, damping devices, 9, lo and return stops 11, 12. Since the wings flip out at high speed and rotation, the wings (the carrier surfaces) will move at a high flip-out speed. In order that the wings are not snapped, a gentle braking to final position must take place. This is achieved as follows. The one, narrower end 13 of the carrier arms is fixedly connected to each respective carrier surface 1, 2, while its other end 14 is pivotally journalled on each respective flip-out shaft 4, 5. The other end carries a substantially circular end surface 15 and abuts against both the damping device and the return stop even in its inwardly closed position. In the inwardly closed position, both damping devices and carrier arms connect to the casing surface of the sub-combat unit. When the carrier arm is twisted out from its inwardly closed position, the damping device (which may consist of a rubber bushing) is compressed by the abutment surface of the carrier arm. The return stop is designed as a leaf spring whose free end 16 resiliently abuts against the end surface 15 of the carrier arm and slides along this during the pivoting movement. When the carrier surfaces have reached their maximum flip-out and the damping devices have been fully compressed, the energy stored in the damping devices will strive to return the carrier surfaces. Consequently, the end surface of the carrier arm is provided with a recess 17 with a substantially radial surface 18 against which the free end 16 of the leaf spring will come into abutment so that a well-defined final flip-out position will be assumed by the carrier surfaces. The rubber damper has been selected such that, in the compressed state, it possesses sufficient latent energy to be able to return the carrier arm to the return stop. The present invention should not be considered as restricted to that described above and shown on the drawings, many modifications being conceivable without departing from the spirit and scope of the appended claims.

Claims: A sub-combat unit arranged to be separated from a flying body, for example a carrier shell or the like, over a target area, the unit including a warhead, a target detector and two diametrically disposed carrier surfaces (1, 2) which via carrier arms (7, 8) are pivotally disposed each on its own shaft (4, 5) located in a plane which is normal to the line of symmetry of the warhead from a collapsed position in which the carrier arms and carrier surfaces connect to the circumferential surface of the sub-combat unit, and to a position opened at 90° at which both of the carrier surfaces form a retarding area for the fall velocity of the sub-combat unit and impart to the sub-combat unit a rotation for scanning the target area in a helical pattern during the fall of the sub-combat unit towards the target area, the unit further including damping devices (9, 10) and return stops (11, 12) disposed adjacent to each carrier surface (1, 2) in connection with the casing of the sub-combat unit, the damping devices being compressed by the carrier arms (7, 8) on flip-out of the carrier surfaces, the return stops (11, 12) creating a stop against which the carrier arms are operative to spring back, characterized in that the end of the carrier arms which is journalled on the flip-out shafts (4, 5) includes an abutment surface which, in the collapsed position, abuts against the damping device (9, 10) and, in the flip-out position, against the return stop (11, 12). The sub-combat unit as claimed in claim 1, characterized in that the abutment surface consits of a recess (17) of the substantially circular end surface (15) of the carrier arm and in which the recess has a substantially radial surface (18) against which the return stop abuts when the carrier surfaces assume their flip-out position. The sub-combat unit as claimed in claim 2, characterized in that the return stop consits of leaf spring (11, 12) or the like whose one end is permanently secured in the casing of the sub-combat unit while its other, free end (16) resiliently abuts against the circular end surface of the carrier arm and, during flip-out of the carrier surfaces, follows the end surface and engages in said recess (17) and restricts the return movement of the carrier arm.

Inventors: AXINGER JAN, ENGMAN PETER, AXINGER, JAN, ENGMAN, PETER
Applicants: BOFORS AB
Application year: 1992
Main classification: F42B12
IPC codes: F42B10