Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
  • F42C1/00—Impact fuzes, i.e. fuzes actuated only by ammunition impact
  • F42C1/02—Impact fuzes, i.e. fuzes actuated only by ammunition impact with firing-pin structurally combined with fuze
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
  • F42C15/00—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
  • F42C15/005—Combination-type safety mechanisms, i.e. two or more safeties are moved in a predetermined sequence to each other
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
  • F42C15/00—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
  • F42C15/18—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges wherein a carrier for an element of the pyrotechnic or explosive train is moved
  • F42C15/188—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges wherein a carrier for an element of the pyrotechnic or explosive train is moved using a rotatable carrier
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
  • F42C15/00—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
  • F42C15/20—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges wherein a securing-pin or latch is removed to arm the fuze, e.g. removed from the firing-pin
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
  • F42C15/00—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
  • F42C15/24—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges wherein the safety or arming action is effected by inertia means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
  • F42C15/00—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
  • F42C15/28—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges operated by flow of fluent material, e.g. shot, fluids
  • F42C15/295—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges operated by flow of fluent material, e.g. shot, fluids operated by a turbine or a propeller; Mounting means therefor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
  • F42C9/00—Time fuzes; Combined time and percussion or pressure-actuated fuzes; Fuzes for timed self-destruction of ammunition
  • F42C9/02—Time fuzes; Combined time and percussion or pressure-actuated fuzes; Fuzes for timed self-destruction of ammunition the timing being caused by mechanical means

Definitions

• the present invention relates to a self-percussive mechanical fuze for a non-rotating ammunition, said fuze comprising a fuze body extending along a central axis between a distal end provided with a cap and a proximal end provided with a connection for assembling said fuze to one ammunition, said fuze comprising a firing pin disposed in said central axis, a primer provided in a primer holder arranged to be rotatable around an axis of rotation parallel and off-center relative to said central axis between at least one storage position in which said primer is off-center relative to said striker and a cocked position in which said primer is aligned with said striker and the pyrotechnic chain of the ammunition, and a mechanism provided with at least two safety devices coupled to said carrier primer to maintain said rocket in a secure state until the appearance of at least two physical phenomena independent of each other related to the firing of said ammunition.
• Mechanical ammunition fuzes are mechanisms whose main function is to ensure the safe maintenance of ammunition in its various life phases (storage, handling, transport, maneuvers in the area of operations, loading of the ammunition and firing), then to ensure the functioning of these ammunition as soon as the required conditions are met, and this by means of purely mechanical safety devices. More specifically, when firing the ammunition, the safety of the ammunition must be guaranteed from the moment it is loaded into a weapon to be fired and up to a distance called “safety distance”, beyond which fired ammunition can no longer have a harmful effect on personnel having used it. The fuse must also authorize the operation of the ammunition (passage from the secure state to the armed state) from a distance called “certain arming distance”. However, the weapons are designed to fire at different loads, making it possible to achieve more or less distant objectives. These charges are characterized among other things by a more or less rapid linear speed of the ammunition.
• Publication WO 03/095933 Al describes another rocket solution equipped with a wind turbine also used to unlock a safety. At the start of the shot, the wind turbine unscrews, goes up, and releases the primer holder which can turn and align the striker on the primer. As in the previous example, this solution does not include any adaptive function.
• US publication 1,916,244 A describes a similar device.
• the present invention aims to overcome these drawbacks by proposing a fuze provided with an exclusively mechanical, reliable and efficient solution for maintaining safety for a non-rotating ammunition, which exploits the relative displacement of the air with respect to the ammunition during its flight as second physical phenomenon independent of the first physical phenomenon linked to the linear acceleration at the start of the shot, this solution being applicable whatever the type of rocket, and having an adaptive function guaranteeing a certain arming distance and a constant safety distance regardless of the load at which the ammunition is fired.
• the invention relates to a rocket of the kind indicated in the preamble, characterized in that it comprises a wind turbine arranged to be driven in rotation by the relative displacement of the air with respect to the ammunition during its flight. and generating the rotational torque necessary for the operation of said mechanism which regulates the time required for the fuze to pass from the safe state to an armed state, thus guaranteeing an expected standoff distance regardless of the load with which the ammunition is fired.
• the invention is advantageous in that it proposes the use of the relative displacement of air by a wind turbine to achieve the second storage security within the meaning of the Stanag 4187 standard for a weapon which does not generate centrifugal effect.
• said wind turbine is provided with a drive shaft, coinciding with the central axis of said rocket body and integral with said striker.
• Said turbine advantageously comprises blades which extend radially from a central zone), and the fairing of said rocket comprises at least one axial air intake orifice in line with said central zone and several discharge orifices of radial air at the exit of said blades to cause the rotation of said wind turbine in a direction of rotation.
• said fuze comprises a locking system arranged to, in the locked position, prevent rotation of the wind turbine and keep the fuze in a secure state before firing the ammunition, and in the unlocked position, allow the rotation of the wind turbine after firing the ammunition.
• said locking system comprises an inertial sleeve associated with a return member, said inertial sleeve being slidably mounted in the central axis of said rocket body, to be movable between said locked position in which said inertial sleeve is secured by said return member in the high position and blocks said wind turbine in rotation, and said unlocked position in which said inertial sleeve moves into the low position under the effect of the linear acceleration at the start of the blow, constrains said return member and releases the rotation of said wind turbine.
• Said locking system may further comprise at least one axial indexing finger provided on one of the parts of said wind turbine or of said inertial sleeve and an axial orifice provided on the other of the parts of said inertial sleeve or of said wind turbine, said axial indexing finger being housed in said axial orifice when said inertial sleeve is in the high position in said locked position to block said wind turbine in rotation.
• Said locking system may also comprise at least one radial guide finger provided on one of the parts of said rocket body or of said inertial sleeve, and an axial groove provided on the other of the parts of said inertial sleeve or of said rocket, said radial guide finger being housed in said axial groove when said inertial sleeve is in the high position in said locked position to block rotation of said inertial sleeve.
• Said locking system may finally comprise a blocking element arranged to hold said inertial sleeve in the low position in said unlocked position.
• Said blocking element may comprise at least one ball in a lateral housing provided in one of the parts of said inertial sleeve or of said rocket body, and a lateral opening provided in the other of the parts of said rocket body or of said sleeve inertial, said ball being arranged to move between said lateral housing and said lateral opening when they face each other.
• said rocket comprises at least one inertial lock arranged to link said primer carrier to said rocket body and maintain said primer carrier in the storage position, said inertial lock forming part of the other of said devices security which has the advantage of reacting to the linear acceleration at the start of the shot.
• Said fuze advantageously comprises at least one locking member arranged to link said primer carrier to said fuze body and hold said primer carrier in the storage position, said locking member forming part of one of said safety devices which has the advantage of reacting to the linear velocity of the ammunition during its flight.
• Said locking member may comprise a ball in said primer holder, trapped in a hemispherical imprint of said rocket body.
• said rocket comprises a rotor superimposed on said primer carrier, and the drive shaft of said wind turbine comprises a motor pinion arranged to mesh with a receiving pinion of said rotor and to drive it in rotation around said axis of rotation.
• said rotor comprises a hemispherical recess arranged to be positioned facing the ball in said primer holder and allow it to rise to release said primer holder.
• Said primer carrier and said rotor are advantageously coupled together by a coupling device over a determined angular sector, during which rotation of said rotor causes rotation of said primer carrier passing from said storage position to said armed position.
• Said coupling device comprises a coupling finger provided on one of the parts of said primer holder or of said rotor, and a circular oblong slot on the other of the parts of said rotor or of said primer holder.
• Said rotor is further provided to mesh with a chronometric gear train arranged to regulate the movement of said rotor.
• said rocket comprises a flange, integral with the drive shaft of said wind turbine, arranged to break under the effect of an impact transmitted by said fairing and allow said striker to descend and strike said primer and initiate the pyrotechnic chain, leading to the destruction of the ammunition.
• FIG. 1 is a plan view of a rocket according to the invention
• Figure 2 is an axial sectional view of the rocket of Figure 1
• Figure 3 is a perspective view of the mechanism contained in the rocket of Figure 2
• Figure 4 is an enlarged sectional view of the part top of the rocket of figure 2, showing the wind turbine in the locked high position
• figure 5 is a view similar to figure 4, showing the wind turbine in the unlocked low position
• figure 6 is a view in section and in perspective of part of the mechanism contained in the rocket of figure 2, showing the rotor driven by the wind turbine, while the primer holder is in the storage position
• figure 7 is a view similar to Figure 6, showing the rotor driven pa r the wind turbine, in an intermediate position
• Figure 8 is a view similar to Figure 6, showing the rotor driven by the wind turbine, moving the primer holder in the cocked position
• Figure 9 is a view section of the fuze
• FIG. 13 is a view similar to FIG. 12, showing the rotor driven by the wind turbine, in an intermediate position in accordance with FIG.
• Figure 14 is a view similar to Figure 12, showing the rotor driven by the wind turbine, moving the primer holder into the cocked position in accordance with Figure 8.
• the invention is particularly concerned with non-rotating ammunition, which is ammunition of elongated shape along a central axis, moving without turning on them- same and are stabilized by empennage.
• ammunition is used, which applies to any type of ammunition, projectiles, rockets, and the like.
• the ammunition (not shown) is not described as such because it does not form part of the invention. It mainly contains explosive charges.
• the invention is more particularly concerned with the fuze which is assembled at the head of the ammunition.
• the rocket contains in known manner a mechanical striker and a percussion primer containing a pyrotechnic component such as a detonator. It allows during the impact of the ammunition on a target, to initiate a pyrotechnic chain which will activate the explosive charges and cause the destruction of the ammunition.
• the self-percussive mechanical fuze 1 for a non-rotating ammunition comprises a substantially frustoconical fuze body 2, extending along a central axis A.
• the fuze body 2 consists of a base 3 provided with a connection 4 to be assembled with the ammunition and with a central housing 5 through to receive the upper part of the ammunition and put the explosive charges in communication with the percussion primer.
• the rocket body 2 further comprises a cap holder 6 surmounted by a cap 7 capable of deforming in the event of impact.
• the cap 7 is linked to the cap holder 6 by radial pins 8 through slots 9 provided in the cap 7, or by any other equivalent assembly means.
• the rocket 1 comprises a mechanism 10 with several security levels to maintain the ammunition in a secure state until the appearance of at least two independent physical phenomena linked to the firing of the ammunition.
• the mechanism 10 is shown in Figure 3 and comprises from top to bottom: - a wind turbine 11 provided with a drive shaft 12 coincident with the central axis A of the rocket,
• an inertial lock 18 arranged on an axis C parallel to the axis of rotation B and housed in a lateral notch 19 of the rotor 15 and of the primer holder 17.
• the upper part of the mechanism 10 is mounted in the cover holder 6.
• the cover holder 6 comprises a central bore 20 whose axis coincides with the central axis A of the rocket, arranged to guide in rotation and in axial translation the drive shaft 12 of the wind turbine 11. It also comprises an annular housing 21 under the wind turbine 11 to receive the inertial sleeve 13.
• the lower part of the mechanism 10 is mounted in a safety holder 22, itself -even mounted in the base 3 of the rocket.
• the blades 23 have a curved shape to generate rotation of the turbine in the direction of arrow R ( Figure 3).
• the central zone 24 has a substantially conical shape provided with a vertex centered on the central axis A and oriented in the direction of the end of the cap 7, forming the distal end 25 of the spindle 1.
• the cap 7 comprises a axial air intake orifice 26 in line with the central zone 24 of the turbine 11 and several radial air discharge orifices 27 at the outlet of the blades 23.
• the drive shaft 12 of the turbine 11 comprises a toothed pinion, called motor pinion 28, arranged to mesh with a receiving pinion 29 integral with the rotor 15 of the primer holder 17.
• the fuze 1 comprises a locking system 30 arranged to, in the locked position, prevent the rotation of the turbine 11 when the fuze 1 is in the storage position before firing the ammunition, and in the unlocked position, allow the rotation of the turbine 11 after firing the ammunition.
• This locking system 30 comprises the inertial sleeve 13, which is mounted to slide axially in the annular housing 21 provided in the cap holder 6 to be movable between the locked position and the unlocked position.
• the locking system 30 further comprises at least one axial indexing finger 32 provided on the body of the turbine 11 and projecting at the inside at least one axial hole 33 provided in the inertial sleeve 13 to prevent the wind turbine 11 from rotating in this locked position.
• the locking system 30 further comprises a locking element 36 arranged to lock the inertial sleeve 13 in the low position when it is in the unlocked position.
• This blocking element 36 comprises a ball 37 provided in a lateral housing 38 of the sleeve and a lateral opening 39 provided in the cap holder 6.
• the inertial sleeve 13 When the inertial sleeve 13 retracts, it causes the ball 37 with it, and when the ball 37 arrives in front of the lateral housing 38, it lodges there and prevents the sleeve to go up.
• any other technical solution fulfilling the same blocking function in the locked position may be suitable.
• the wind turbine 11 thus released is maintained in its initial high position by a collar 40 projecting radially from its drive shaft 12 which rests on the cap holder 6, also maintaining the striker 14 in the high position.
• the primer holder 17 has a safety function and makes it possible to maintain a primer 17' off-center or misaligned with respect to the pyrotechnic chain and to the striker 14.
• the axis of the pyrotechnic chain coincides with the central axis A.
• primer 17 is associated with safety devices provided in the mechanism 10 to maintain the ammunition in a secure state during the storage, transport, handling and loading phases of the ammunition in a weapon until the start of the shot and even after the shot has fired from a predetermined safe distance. This position of primer holder 17 is called a storage position.
• the safety devices provided in the mechanism 10 allow the primer holder 17 to move to align the primer 17' with the striker 14 and the pyrotechnic chain. This position of the primer holder is called an armed position.
• the primer holder 17 is held in the storage position by two independent safety elements: the inertial lock 18 of axis C on the one hand, and a locking member 41 on the other hand.
• the principle of an inertial lock 18 is commonly used in the field of ammunition.
• the inertial lock 18 comprises an inner mass 50, secured in the high position by an inner spring 51, a ball 52 housed radially between the inertial lock 18 and the inner mass 50, and a external spring 54 to secure the inertial lock 18 in the high position corresponding to the storage position.
• the internal mass 50 descends and compresses the internal spring 51.
• the ball 52 disappears in a peripheral clearance 53 of the internal mass 50 and releases the inertial lock 18.
• the inertial lock 18 descends , compresses the outer spring 54 and unlocks the primer holder 17.
• the inner mass 50 rises and locks the inertial lock 18 in the low position via the ball 52 which is housed radially between the inertial lock 18 and a radial clearance 55 provided in the safety carrier 22. Any other technically equivalent inertial means may be suitable.
• the locking member 41 is arranged to link the primer holder 17 to the safety holder 22, itself linked to the rocket body 2. It comprises a ball 42 provided in a Axial through housing 43 provided in the primer holder 17 and trapped in a hemispherical recess 44 provided in the security holder 22. Any other technically equivalent locking means may be suitable.
• the wind turbine 11 is released and the inertial lock 18 releases the primer carrier 17 and simultaneously the rotor 15.
• the primer carrier 17 remains fixed, in the storage position, until the rotor 15 driven by the turbine 11 travels a determined angular stroke, and a hemispherical recess 45 provided in the rotor 15 is positioned opposite the ball 42 housed in the holder - primer 17, to allow it to rise and release the primer holder 17.
• any other technically equivalent indexing means may be suitable.
• the primer holder 17 is then coupled to the rotor 15 by a coupling device 46 so that the rotation of the rotor 15 causes the rotation of the primer holder 17 which passes from the storage position (FIG. 6) to the cocked position (FIG. 8).
• the coupling device 46 comprises a coupling finger 47 provided on the primer holder 17 and a circular oblong slot 48 provided on the rotor 15.
• the reverse configuration could also be suitable, in which the finger of coupling is on the rotor and the circular oblong lumen is on the primer holder.
• the coupling finger 47 is arranged to circulate in the oblong circular slot 48 over the determined angular sector during which the rotation of the rotor 15 does not cause the rotation of the primer holder 17.
• the slot 48 comes into abutment against the finger coupling 47 then the primer carrier 17 is coupled to the rotor 15 and can be rotated.
• any other technically equivalent coupling means may be suitable.
• rocket 1 The operation of rocket 1 according to the invention is described below.
• the fuze 1 assembled with ammunition is in a secure state, since the primer 17 'integrated in the primer holder 17 is misaligned from the pyrotechnic chain and the striker 14.
• the primer holder 17 constitutes the switch of the pyrotechnic chain, and is itself held in the misaligned position by the two independent safety elements:
• the wind turbine 11 is itself kept fixed over two degrees of freedom: in axial translation, by the return member 31 of the locking system 30 which keeps it pressed upwards against the cap 11, via the inertial sleeve 13, and in rotation by the axial indexing pin 32 housed in the corresponding axial orifice 33 of the inertial sleeve 13, itself locked in rotation via the radial guide pin 34.
• the inertial lock 18 retracts and releases the primer holder 17 and the rotor 15. Simultaneously, the inertial sleeve 13 of the locking system 30 of the turbine moves downwards in the annular housing 21 of the cap holder 6.
• the ball 37 of the locking element 36 located in the lateral housing 38 of the inertial sleeve 13 descends at the same time , and, as soon as it encounters the side opening 39 provided in the headdress holder 6, lodges there.
• the ball 37 acts as a lock and blocks the rise of the inertial sleeve 13.
• the wind turbine 11 is released and driven in rotation by the air flow generated by the flight of the ammunition.
• the rotation of the wind turbine 11 creates the driving energy of the rotor 15 and transmits it to it via the drive shaft 12 of the turbine with which it meshes.
• the chronometric gear train 16 regulates the rotational movement of the rotor 15.
• the primer holder 17 is always held in the storage position by the action of the ball 42 of the locking member 41, positioned in the hemispherical recess 44 of the security holder 22 (FIGS. 6 and 12).
• the drive shaft 12 brings the primer holder 17 into the cocked position, the latter now being linked to the rotor 15 via the coupling pin 47 and the ball 42. Meanwhile, the rotor 15 is no longer connected to the timing gear train 16, and the alignment of the primer holder 16 is instantaneous (FIGS. 8 and 14). On impact with a target
• the drive shaft 12 of the turbine 11, which is coincident with the striker 14, is located opposite the primer 17 'which contains the detonator of the pyrotechnic chain.
• the collar 40 which holds the drive shaft 12 of the turbine and of the striker 14 at its initial height, is dimensioned in order to remain intact during the phases of storage, departure of the shot and flight of the ammunition, but not to resist an impact on a target. Under the effect of the impact transmitted by the cap 7, the collar 40 breaks and allows the firing pin 14 to descend to strike the primer 17' and initiate the pyrotechnic chain, resulting in the destruction of the ammunition by explosion.
• the relative displacement of the air during the flight of the ammunition generates the motor torque necessary for the alignment of the primer holder 17 with the striker 14 and the pyrotechnic chain.
• the rotational torque transmitted by the wind turbine 11 is directly related to the speed of movement of the ammunition.
• the drive shaft 12 of the wind turbine 11 fulfills a triple function: holding the mechanism 10 in the safety position, transmitting the torque to the primer holder 17 and percussion of the primer 17'.
• the present invention is of course not limited to the exemplary embodiments described but extends to any modification and variant obvious to a person skilled in the art while remaining within the limits of the appended claims.
• the invention extends to any other non-revolving ammunition or projectile, such as, for example, illuminating ammunition, etc.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Wind Motors (AREA)
• Earth Drilling (AREA)
• Fuses (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=79018450

Family Applications (1)

Country Status (4)

Families Citing this family (1)

Family Cites Families (13)

• 2021
  • 2021-09-27 FR FR2110056A patent/FR3127563B1/fr active Active
• 2022
  • 2022-07-07 US US18/683,160 patent/US12038262B1/en active Active
  • 2022-07-07 WO PCT/EP2022/068865 patent/WO2023046327A1/fr not_active Ceased
  • 2022-07-07 EP EP22741258.2A patent/EP4409223A1/de active Pending

Also Published As

Similar Documents

Legal Events