Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B14/00—Projectiles or missiles characterised by arrangements for guiding or sealing them inside barrels, or for lubricating or cleaning barrels
  • F42B14/06—Sub-calibre projectiles having sabots; Sabots therefor
  • F42B14/061—Sabots for long rod fin stabilised kinetic energy projectiles, i.e. multisegment sabots attached midway on the projectile
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B14/00—Projectiles or missiles characterised by arrangements for guiding or sealing them inside barrels, or for lubricating or cleaning barrels
  • F42B14/02—Driving bands; Rotating bands

Definitions

• the present invention relates to ammunition for small, medium and large caliber weapons, and more particularly to an improved launcher with improved sealing, for ammunition of the type comprising an undersized bullet and a launcher, in particular for hunting or training weapons.
• the launch techniques frequently used today use a launcher generally consisting of two or more elements surrounding the sub-projectile.
• the elements of the launcher assembled together in contiguous planes by a locking system, can be made of metal alloys or plastic.
• the aerodynamic forces exerted on the projectile at the exit of the weapon cause the separation of the elements of the launcher which, after separation, each follow their own trajectory and fall at varying distances from the weapon.
• patent FR-A-2,555,728 describes ammunition for hunting weapons comprising an under-calibrated projectile stabilized by empennage, comprising a tapered bullet of dense alloy associated with a launcher made of plastic.
• patents FR-A-2,599,828 and FR-A-2,606,500 describe hunting bullets of the type comprising a sub-projectile and a launcher made of several detachable elements, the characteristics of which are improved.
• patent FR-A-2,599,828 describes a bullet with great stability on trajectory, and therefore providing good shooting precision, but destabilizing beyond a certain distance.
• Patent FR-A-2,606,500 relates to ammunition providing a high initial speed and limiting the violence of the recoil shock, constituted by an undersized bullet and a launcher of the caliber of the weapon, comprising an open external annular chamber, separated from the propellant charge by a partition liable to rupture under the pressure of the gases generated by the combustion of the charge.
• One of the difficulties faced by this technique of the sub-calibrated bullet associated with a launcher is that of sealing, and more particularly sealing against propellant gases when the charge is ignited. Although these difficulties are encountered very particularly in the case of launchers in two or more elements, the problem of sealing also arises in the case of monoblock launchers.
• it is essential that the presence of the launcher does not interfere with the cartridge-filling operations during which the sub-projectile and the launcher are placed in a cartridge comprising a primed cartridge case and a charge of propellant powder.
• the present invention specifically relates to a launcher with improved sealing for ammunition of the type comprising a launcher associated with a sub-projectile on which it can adapt, comprising one or more elements and at least one peripheral seal.
• a subject of the invention is also a launcher for ammunition of the type comprising a launcher associated with a sub-projectile on which it can be adapted, providing both an improved seal against combustion gases and a reduction of the recoil shock of the weapon.
• the invention also relates to a complete bullet consisting of an under-calibrated projectile associated with a launcher, and comprising an optimized seal.
• the launcher according to the present invention is distinguished in that it comprises at least one seal continuously encircling the external face and the internal face of each element, each seal preferably consisting of a single piece.
• each element of the launcher is crossed by one or more perforations ensuring the joining of the joint, and the launcher of the invention preferably comprises at least two separable elements.
• the joint covers at least in part not only the external face, but also the internal face and the edge of the junction plane of each launcher element, and it has a thickness such that it exceeds beyond the surface. external, of the internal surface, and of the junction plane, from a distance between 0 and 1 mm, and preferably between 0.1 and 0.5 mm in the case of hunting ammunition.
• the seal can be formed on each element of the launcher by molding in a flexible material chosen from natural or artificial rubbers, and for example in vulcanizable rubber or in thermoplastic elastomer, preferably having excellent adhesion to the material constituting the launcher, and containing, where appropriate, usual fillers intended to improve the mechanical properties thereof, for example an anti-ultraviolet agent improving resistance to aging or a lubricating agent intended to facilitate sliding against the wall of the barrel of the weapon.
• the hardness of the rubber used is chosen according to the conditions of use, and it is generally between 20 and 120 (Shore hardness), and preferably between 50 and 90.
• each element is crossed by one or more perforations allowing the material to pass during the molding of the seal.
• the seal disposed on the rear part of the launcher element preferably comprises an annular seal closing the space between the launcher and the internal wall of the sleeve, delimiting an external annular chamber in the immediate vicinity of the load.
• this cover deforms, causing the chamber containing the charge to communicate with the external annular chamber, and allowing thus the relaxation of the gases. This results in a reduction in the recoil shock felt by the user of the weapon, as well as an optimization of the speed of combustion of the powder.
• the launcher When the launcher has a single seal, it is preferably placed on the front part of each element. In fact, the tests carried out with the ammunition in accordance with the invention have shown that this arrangement facilitates the cartoning operations.
• front part within the meaning of the invention means the area formed approximately by half of the launcher located towards the front of the projectile.
• the seal according to the present invention is preferably placed in this front part, and more preferably at a distance from the front edge of the launcher representing less than 30% of the length of the launcher.
• the part of the launcher located in front of the joint can be independent of the other part.
• it then consists of two cylindrical elements arranged longitudinally on the same axis and separated by the seal attached to the edge of one of the two elements.
• the seal is arranged at the front end of the launcher, of which it envelops the front face, the latter preferably comprising transverse notches facilitating the attachment of the seal to the launcher and the 'assembly of the elements when the launcher is in two or more elements.
• the launcher with improved sealing in accordance with the present invention can be made of metal or of a metal alloy, for example of aluminum alloy, or alternatively of plastic material produced by molding or by injection, for example of polyamide.
• the invention also relates to a method for manufacturing a launcher with improved sealing for ammunition of the type comprising a launcher associated with a sub-projectile, comprising one or more elements each comprising an integrated flexible seal.
• thermoplastic elastomer or vulcanizable rubber is carried out directly on each element of the launcher, on a part of the wall of the launcher crossed by perforations.
• the device according to the present invention is applicable in all ammunition, of small, medium or large caliber, of the type comprising an under-calibrated projectile, for example a sub-calibrated bullet, and a launcher made up of one or more separable elements, in the field of hunting, sport or training weapons, and preferably in that of hunting weapons.
• This device is inserted in an assembly constituted by a cartridge, which consists of: a primed socket; a charge of propellant powder; a complete bullet comprising a launcher according to the invention, of the caliber of the weapon, and a sub-calibrated bullet.
• the present invention provides the advantage of reducing the standard deviation of pressure and speed. , and therefore to decrease the dispersion of the shot. In addition, there is no disturbance in the trajectory of the sub-projectile.
• Figure 1 a half-section view of a complete bullet, comprising an undersized bullet and a launcher with improved sealing according to the invention.
• Figure 2 a half-section view showing a second embodiment of the launcher according to the invention, comprising a seal in the rear part.
• Figure 3 a half-section view showing another embodiment of the launcher according to the invention, comprising a seal in the front part.
• Figure 4 a half-section view showing another embodiment of the launcher according to the invention, comprising two seals.
• Figure 5a a front view of a variant of the launcher of the invention comprising a seal in the front part, corresponding to the embodiment of Figure 5b.
• Figure 5b a partial sectional view along AA of the launcher of Figure 5a.
• Figure 1 shows, in half-view, a cartridge comprising a launcher element (1) of substantially semi-cylindrical shape, a cartridge case (2), a primer (3) and a propellant charge (4).
• the shape of the internal wall of the launcher (1) is intended to adapt in known manner to the body of the sub-calibrated bullet (5) of the arrow-bullet type.
• the internal face of the launcher has teeth (6) cooperating with grooves (7) formed on the body of the ball (5).
• the launcher has on its external face annular grooves of substantially semi-circular section (8 and 9) forming decompression grooves, and limiting the friction surface in the barrel of the weapon.
• the front part (10) of the launcher has a conical internal surface (11) of diameter widening from the rear towards the front, in order to facilitate the separation of the launcher element under the effect of the aerodynamic forces s' exerting at the exit of the barrel of the weapon.
• the rear part (12) has an annular skirt (13) and a groove (14), at the level of the connection with the body of the launcher element.
• the skirt (13) is crossed by two series of perforations (15) arranged in a transverse plane, each series can include, for example, 3 or 4 perforations in the wall of the launcher.
• the annular skirt (13) is truncated at its two ends so that its section is not entirely semi-circular but covers an arc of approximately 170 °; thus the two launcher elements (1) put in place are not joined by the edges of their respective annular skirts (13) but a space is provided between them, in which the seal takes place as indicated below.
• the seal (16) envelops the entire annular skirt (13) and the groove (14), and the natural or artificial rubber which constitutes it fills the perforations (15) passing through the wall. It projects slightly beyond the external surface of the launcher (1), above the groove (14) to seal, on the one hand with the wall of the socket, preventing any infiltration of the gases generated by the combustion propellant charge (4), on the other hand with the inner wall of the tube, after firing.
• the seal (16) also protrudes slightly beyond the junction plane of the launcher elements, so that the two launcher elements once assembled, are joined by their respective seals (16) which are strongly compressed l one against the other.
• the protrusion beyond the external surface and beyond the junction plane is of the order of 0.3 to 0.5 mm in the case of hunting ammunition.
• FIG 2 is a variant of the launcher of Figure 1 where the seal (17) is formed in an annular groove (18) whose bottom is pierced by openings (19) passing through the entire wall of the element (1) of the launcher. As shown in Figure 2, the seal (17) completely envelopes the launcher element (1) and has an edge (17a) projecting in the junction plane of the two launcher elements.
• each launcher element (1) has a seal (20) placed in a groove (21) provided in the front part of the launcher. This groove is pierced by a series of perforations (22) passing through the wall of the launcher, ensuring the formation of the seal also on the internal wall of the launcher.
• the seal (21) has a slightly flattened shape ensuring good sealing contact with the wall of the sleeve and the internal wall of the tube, in the launching phase.
• the variant of improved waterproof launcher shown in Figure 4 comprises two seals, one (16) identical to that of Figure 1, arranged on the rear part of the element (1) of the launcher, the another (20) formed by overmolding in the annular groove (21) located in the front part of the launcher.
• the bottom of this groove (21) has a series of perforations (22) passing through the thickness of the wall, and facilitating the overmolding of the thermoplastic elastomer or of the vulcanizable rubber which fills any the annular groove (21) over its entire length, penetrates into the perforations (22) and envelops the launcher in the plane of this groove.
• a seal (23) can be provided on the seal (16).
• This cover is preferably formed by molding the seal in thermoplastic elastomer or vulcanizable rubber and is an integral part thereof. Its height is such that the peripheral edge of the cover (23) is in contact with the internal wall of the sleeve (2) when the bullet is placed in the cartridge.
• this seal (23) defines with the seal (16) and the wall of the sleeve an external annular chamber which is in the immediate vicinity of the propellant charge.
• the cover (23) deforms, thereby causing the chamber containing the charge to communicate with the external annular chamber, and thus allowing the gas relaxation. This ensures a reduction in the recoil shock felt by the user of the weapon.
• the variant embodiment shown in Figures 5a and 5b comprises the same launcher element (1) as in the previous Figures, but the seal (24) is fixed to the front end of the launcher (1), on its front part which it envelops by partially covering it.
• the front part of the element (1) comprises an annular rib (25) crossed by several perforations, as well as three notches (26, 27, 28) transverse, intended to strengthen the attachment of the seal. (24) in natural or artificial rubber on the element (1) of the launcher.
• the seal (24) completely covers the three notches but leaves the enlarged front face of the rib (25) visible.
• a notch (26) is provided in the central part of the front part of the element (1) and the other two notches (27, 28) are provided at each of the two ends.
• the seal (24) completely fills the volume of the notches (26, 27, 28) and protrudes slightly beyond the outer and inner surfaces of the element (1) and in the plane of junction of two elements (1) to ensure a good seal at the same time in the cartridge case, and in the barrel after firing.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Toys (AREA)
• Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)
• Manipulator (AREA)
• Portable Nailing Machines And Staplers (AREA)
• Gasket Seals (AREA)
• Emergency Lowering Means (AREA)
• Fishing Rods (AREA)
• Pens And Brushes (AREA)
• Electron Sources, Ion Sources (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9512143

Family Applications (1)

Country Status (9)

Family Cites Families (8)

• 1997
  • 1997-10-13 FR FR9712754A patent/FR2769700B1/fr not_active Expired - Lifetime
• 1998
  • 1998-10-06 WO PCT/FR1998/002127 patent/WO1999019685A1/fr active IP Right Grant
  • 1998-10-06 CA CA002305549A patent/CA2305549C/fr not_active Expired - Fee Related
  • 1998-10-06 PT PT98947606T patent/PT1023573E/pt unknown
  • 1998-10-06 ES ES98947606T patent/ES2169927T3/es not_active Expired - Lifetime
  • 1998-10-06 DE DE69803401T patent/DE69803401T2/de not_active Expired - Lifetime
  • 1998-10-06 EP EP98947606A patent/EP1023573B1/de not_active Expired - Lifetime
  • 1998-10-06 AU AU94461/98A patent/AU9446198A/en not_active Abandoned
  • 1998-10-06 AT AT98947606T patent/ATE211539T1/de active

Non-Patent Citations (1)

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