An inertial firing module for rifled artillery fuze capable of preventing ballistic explosion

Abstract

The present invention discloses an inertial firing module for a rifled artillery fuze that can prevent ballistic explosion. The module comprises an end cap, an outer shell, an energy storage needle firing mechanism, a forward overload and unload identification mechanism for controlling the energy storage needle firing mechanism, a centrifugal safety mechanism for the forward overload and unload identification mechanism, and an anti-recovery mechanism for the centrifugal safety mechanism. The forward overload and unload identification mechanism primarily comprises a movable body and a movable body spring for identifying forward overload, and a sliding sleeve, a sliding sleeve spring, and a first ball for identifying unload. Several centrifugal pins disposed within blind holes surrounding the movable body use the frictional force generated by the centrifugal force acting on the inner wall of the outer shell to resist the abnormal forward thrust experienced by the movable body when the projectile's nutation angle returns to zero on the external trajectory. The movable body's center of mass is adjusted to the axis of the inertial firing module through radial drilling, so that its radial eccentricity relative to the projectile axis is close to zero. This prevents the movable body from accidentally releasing the energy storage needle firing mechanism on the external trajectory, thereby causing ballistic explosion.

Description

Technical Field

[0001] The invention belongs to fuze structure design, and in particular relates to an inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion. Background Art

[0002] The fuze is a crucial component of the projectile warhead and the entire ammunition. It is the final actuator for the weapon system to exert its terminal effect, and its effectiveness directly determines the success or failure of the weapon system in engaging the target. During the exterior ballistic phase, the internal components of the fuze of a rotating, uncontrolled projectile are subjected to the effects of the flight environment, including creep forces, oscillation forces, centrifugal inertia, and Gordian knot forces. These ballistic environmental forces can cause the fuze to misfire, prematurely explode, or prematurely explode. According to incomplete statistics, there have been over a hundred documented fuze premature explosion incidents since the founding of the People's Republic of China, involving dozens of models, forcing a large number of fuzes to be repaired, decommissioned, or scrapped. A significant proportion of these premature explosion incidents are caused by a failure to fully consider the ballistic environment during fuze design.

[0003] Currently, fuzes are commonly designed with a safety and arming mechanism. While this ensures fuze safety during handling and firing, significantly reducing the likelihood of chamber and premature detonation, premature detonation, or ballistic detonation, still occurs. When a ballistic detonation occurs, the fuze's safety and arming mechanism is already functioning and the safety arm is disarmed. Therefore, the primary cause of a ballistic detonation is the external ballistic environment to which the fuze is subjected. During projectile and fuze design, unclear understanding of the ballistic environment, inaccurate numerical calculations, and, in particular, insufficient knowledge of the projectile's external ballistic motion around the center, can result in inertial forces exceeding expectations on the fuze's internal components during external ballistic flight, potentially leading to unexpected fuze firing and a ballistic detonation.

[0004] From the law of the projectile's centripetal motion during its exterior ballistic flight obtained by solving the differential equations of the projectile's rigid body trajectory, and the calculation results of the mathematical model of the axial overload of the internal components of the exterior ballistic fuze mentioned in "Analysis of the Exterior Ballistic Mechanics of Rotating Projectile Fuze and Research on the Factors Affecting Ballistic Explosion" (Hui Jianhao. Analysis of the Exterior Ballistic Mechanics of Rotating Projectile Fuze and Research on the Factors Affecting Ballistic Explosion, Nanjing: Nanjing University of Science and Technology, 2024), it can be seen that during the exterior ballistic flight of the projectile, if the internal components of the fuze are eccentric, then when the nutation angle of the projectile instantaneously approaches zero, the axial overload of the internal components of the fuze will have an abnormal mutation. At this time, the axial overload of the internal components will have a large peak value. If this peak value is greater than expected (such as the resistance of the ballistic safety spring), it will cause the internal components of the fuze, such as the inertial components such as the active striker, to "rush forward" abnormally, thereby causing the fuze to fire unexpectedly, resulting in premature explosion, that is, ballistic explosion.

[0005] Current measures to prevent ballistic explosions involving inertia-firing fuzes primarily rely on increasing the resistance of the ballistic safety spring to counteract the inertial force of the abnormal "forward surge" along the trajectory. There are two main types of resistance elements: one uses elastic components such as springs and spring leaves to provide resistance. These are recoverable elastic fuses and can be tested nondestructively, but the spring resistance depends on the spring's structural parameters and is difficult to increase due to limited available space. The other uses rigid components such as lugs and shear pins to provide resistance. These are "rigid fuses" that collapse in a one-time manner, but the resistance is highly dispersed and difficult to test nondestructively. The document "Centrifugal Ballistic Safety Technology of Fuze Inertial Firing Mechanism" (Li Zuohua, Zhang Dayong. "Journal of Detection and Control", Issue 2, 2021, pp. 10-14) discloses a centrifugal ballistic safety technology solution for the inertial firing mechanism derived from the fuze centrifugal ball self-destruction technology. It uses the support reaction force generated by the "self-destruction ramp" structure to limit the axial relative displacement between the inertial part and the shell to obtain the fuze ballistic safety capability, but this requires changing the structure of the entire inertial firing module and multiple parts therein. The entire fuze inertial firing module needs to be redesigned and developed.

[0006] The inertia firing module of the US military's M739A1 fuze, which has been the subject of numerous ballistic explosions both domestically and internationally, operates as follows: During normal operation and in service, the four small steel balls in the inertia firing mechanism are locked in the firing pin's groove via the firing pin seat. The small steel balls are blocked by the slide and cannot move. The two large steel balls are trapped between the semicircular groove of the movable body and the cylindrical surface of the firing pin seat, preventing them from moving. Two centrifugal springs, each with its own external centrifugal spring, are symmetrically mounted in the inclined groove of the movable body, with their heads partially locked in the firing pin seat, preventing the movable body from moving. During firing, the centrifugal springs, the preload of the centrifugal springs, the recoil, and the friction generated by the centrifugal force prevent the centrifugal springs from flying apart, ensuring the correct structural position of the movable body within the chamber. During external ballistics, the recoil of the centrifugal springs has dissipated, and the centrifugal force causes the two centrifugal springs to fly apart. Simultaneously, the locking plate, driven by its centrifugal torque, rotates to block the centrifugal springs, preventing them from returning to their original position. At this point, the centrifugal safety of the movable body is released. However, at this point, the movable body remains in the safe position due to the pre-stressed movable body spring, and is axially limited by the end cap, ensuring exterior ballistic safety. Initially, as the projectile penetrates the target, the movable body thrusts forward, compressing the movable body spring and releasing the large steel ball. Centrifugal force throws the large steel ball loose, releasing the slide. However, the slide remains in position during penetration, subject to significant forward force, locking the two small steel balls that control the firing pin. As the projectile continues to penetrate the target, nearing its end and the forward force on the slide is less than the resistance of the slide spring (projectile deceleration drops to approximately 300g), the slide moves backward under the resistance of the slide spring, releasing the small steel ball and, in turn, the firing pin. The firing pin spring then pushes the firing pin to pierce the needle detonator (along the fuze axis, not shown) located below it within the horizontal rotor. The detonator ignites, subsequently detonating the guide tube and booster tube, completing the fuze's predetermined self-adjusting, delayed inertia firing function.

[0007] The inertial firing mechanism of the M739A1 fuze utilizes an elastic safety element, a spring, which provides limited spring resistance and its ability to withstand abnormal axial overloads on the spring. Due to the limited internal space of the fuze, increasing the spring resistance would inevitably require changing the spring's structural parameters, occupying even more space, making it difficult to improve the standard product. Existing efforts and attempts to increase the spring resistance within the available space have reduced the probability of ballistic detonation but cannot completely eliminate it. Therefore, effective structural measures are needed to address this issue. Summary of the Invention

[0008] The purpose of the present invention is to provide an inertial ignition module for rifled artillery fuzes that can prevent ballistic explosions, thereby preventing ballistic explosion accidents caused by abnormal "forward" overload when the nutation angle of the projectile approaches zero instantaneously on the external trajectory.

[0009] The technical solution for realizing the present invention is: an inertial ignition module for a rifled artillery fuze capable of preventing ballistic explosion, comprising a housing, an end cover, a support, an energy storage needle piercing ignition mechanism, a forward overload and unloading identification mechanism for controlling the energy storage needle piercing ignition mechanism, a centrifugal safety mechanism for the forward overload and unloading identification mechanism, and an anti-recovery mechanism for the centrifugal safety mechanism. The support is in the shape of a rotating body and is axially arranged inside the shell. The energy storage needle puncture ignition mechanism is arranged in the axial through hole of the support. The forward overload and unloading identification mechanism for controlling the energy storage needle puncture ignition mechanism is arranged in the annular space formed by the outer side of the support and the inner side of the shell. The energy storage needle puncture ignition mechanism is controlled by the paired radial through holes in the middle of the support and the second balls therein. The centrifugal safety mechanism of the forward overload and unloading identification mechanism and the anti-recovery mechanism of the centrifugal safety mechanism are both arranged below the shell and blocked by the end cover. The forward overload and unloading identification mechanism for controlling the energy storage needle puncture ignition mechanism includes a shell, an end cover, a support, a baffle, a sleeve, a sleeve spring, a second ball, a first ball, a movable body, a movable body spring and a centrifugal pin, wherein the sleeve , sliding spring, second ball, first ball are mainly used to identify the unloading environment and control the energy storage needle puncture firing mechanism; the shell, movable body, movable body spring and centrifugal pin are mainly used to identify forward overload, and the centrifugal pin is arranged in several radial blind holes symmetrically distributed along the radial direction of the movable body. The centrifugal pin is subjected to the centrifugal force generated by the rotation of the projectile so that its outer end is close to the inner wall of the shell. When the projectile is in the process of outer ballistic flight and the abnormal axial overload caused by the instantaneous nutation angle approaching zero causes the movable body to move unexpectedly axially, the friction force generated by the centrifugal force of the centrifugal pin on the inner wall of the shell and the resistance of the movable body spring jointly resist the inertia force generated by the abnormal axial overload, thereby preventing the movable body from accidentally releasing the first ball and then releasing the energy storage needle puncture firing mechanism to cause a ballistic explosion. The centrifugal force of the centrifugal pins generates friction to counteract the inertial force generated by abnormal axial overload, exhibiting ballistic adaptive characteristics. That is, when the projectile velocity is high, the rotational speed is also high, resulting in a large abnormal axial overload and the resulting inertial force, but the friction generated by the centrifugal pins is also large. Conversely, when the projectile velocity is low, the rotational speed is also low, resulting in a small abnormal axial overload and the resulting inertial force, and the friction generated by the centrifugal pins is also small. Therefore, this structure and principle for preventing ballistic explosions has a minimal impact on the triggering sensitivity of the fuze. The centrifugal pins are symmetrically distributed along the axis of the movable body, without changing the radial eccentricity of the movable body. There are eight centrifugal pins. Two radial blind holes are symmetrically bored along the circumferential surface of the upper side of the movable body. By adjusting the diameter, depth, and position of the two blind holes, the radial eccentricity of the movable body can be brought close to zero, thereby significantly reducing the "forward surge" overload peak caused by the projectile's nutation angle approaching zero during its outer ballistic flight.

[0010] Compared with the prior art, the present invention has the following significant advantages:

[0011] (1) Based on the existing mature technology, the external ballistic environment to which the fuze is subjected is fully considered. Only the internal inertial components of the fuze are changed on the basis of the existing mature inertial ignition module. By utilizing the centrifugal inertial force it is subjected to, the ability to resist abnormal "forward" overload is greatly improved without affecting the original function. There is no need to redesign the inertial ignition module.

[0012] (2) The centrifugal force of the centrifugal pin is used to generate friction to resist the influence of abnormal axial overload, which has ballistic adaptive characteristics. That is, when the projectile speed is high, the rotation speed is also high, the abnormal axial overload is large, but the friction generated by the centrifugal pin is also large. When the projectile speed is low, the rotation speed is also low, the abnormal axial overload is small, and the friction generated by the centrifugal force of the centrifugal pin is also small. Therefore, the structure and principle of preventing ballistic explosion have little effect on the triggering sensitivity of the fuze.

[0013] (3) The overall structure of the fuze is user-friendly, highly feasible, simple in structure, short in improvement cycle and low in cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a cross-sectional view along section AA of an inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion according to the present invention.

[0015] Figure 2 This is a bottom view of an inertial firing module for a rifled artillery fuze capable of preventing ballistic explosion according to the present invention.

[0016] Figure 3 This is a partial cross-sectional view along the BB section of an inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion according to the present invention.

[0017] Figure 4 This is a partial cross-sectional view of the centrifugal sub-component of the inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion according to the present invention in the released state.

[0018] Figure 5 This is a partial cross-sectional view of the inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion according to the present invention, taken along the CC section.

[0019] Figure 6 It is a partial cross-sectional view along the DD section of an inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion according to the present invention.

[0020] Figure 7 This is an axonometric view of the living body in the inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion as described in the present invention.

[0021] Figure 8 This is a front view of a living body in an inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion as described in the present invention.

[0022] Figure 9 The present invention provides a right side view of a movable body in an inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion.

[0023] Figure 10 This is a partial cross-sectional view of the movable body along the EE section in the inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion as described in the present invention.

[0024] Figure 11 This is an axonometric view of a locking piece in an inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion as described in the present invention.

[0025] Figure 12 The following is the variation law of the rotational angular velocity of a 155mm caliber artillery grenade obtained by simulation under the conditions of initial velocity 930m / s and firing angle 51°.

[0026] Figure 13 The axial overload variation law obtained by simulation of a 155mm caliber artillery grenade under the conditions of launching with an initial velocity of 930m / s and a firing angle of 51° without adjusting the eccentricity of the movable body mass.

[0027] Figure 14 The axial overload variation law of a 155mm caliber artillery grenade is obtained by simulation after adjusting the mass eccentricity of the active body under the conditions of launching at an initial velocity of 930m / s and a firing angle of 51°.

[0028] In the figure, 1 is the outer shell, 2 is the end cover, 3 is the support, 4 is the energy storage needle pricking firing mechanism, 41 is the firing pin, 42 is the firing pin spring, 5 is the forward overload and unloading identification mechanism for controlling the energy storage needle pricking firing mechanism, 51 is the baffle, 52 is the sliding sleeve, 53 is the sliding sleeve spring, 54 is the second ball, 55 is the first ball, 56 is the movable body, 57 is the movable body spring, 58 is the centrifugal pin, 6 is the centrifugal safety mechanism of the forward overload and unloading identification mechanism, 61 is the centrifugal, 62 is the centrifugal spring, 63 is the spring plug, 7 is the anti-recovery mechanism of the centrifugal safety mechanism, 71 is the locking plate, and 72 is the locking plate shaft. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the embodiment of the present invention, all directional indications (such as up, down, left, right, front, back, etc.) are only used to explain the specific posture (such as the attached Figure 1The relative positional relationship and movement of the components under the display (as shown) are shown. If the specific posture changes, the directional indication will also change accordingly. In addition, the descriptions of "first" and "second" in the present invention are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly specifying the number of the indicated technical features.

[0031] The following will further introduce the specific implementation methods, technical difficulties and inventive points of the present invention in combination with this design example.

[0032] Combine Figures 1 to 11 The inertial ignition module of a rifled artillery fuze capable of preventing ballistic explosion described in the present invention includes a shell 1, an end cover 2, a support 3, an energy storage needle piercing ignition mechanism 4, a forward overload and unloading identification mechanism 5 for controlling the energy storage needle piercing ignition mechanism, a centrifugal safety mechanism 6 of the forward overload and unloading identification mechanism, and an anti-recovery mechanism 7 of the centrifugal safety mechanism. The support 3 is in the shape of a rotating body and is axially arranged inside the shell 1. The energy storage needle puncture ignition mechanism 4 is arranged in the axial through hole of the support 3. The forward overload and unloading identification mechanism 5 for controlling the energy storage needle puncture ignition mechanism is arranged in the annular space formed by the outer side of the support 3 and the inner side of the shell 1. The energy storage needle puncture ignition mechanism 4 is controlled by the paired radial through holes in the middle of the support 3 and the second ball 54 therein. The centrifugal safety mechanism 6 of the forward overload and unloading identification mechanism and the anti-recovery mechanism 7 of the centrifugal safety mechanism are both arranged below the shell 1 and blocked by the end cover 2. The forward overload and unloading identification mechanism 5 for controlling the energy storage needle puncture ignition mechanism includes the shell 1, the end cover 2, the support 3, the baffle 51, the sleeve 52, the sleeve spring 53, the second ball 54, the first ball 55, the movable body 56, the movable body spring 57 and the centrifugal pin 58, wherein the sleeve 52, the sleeve spring 5 3. The second ball 54 and the first ball 55 are mainly used to identify the unloading environment and control the energy storage needle piercing firing mechanism 4; while the shell 2, the movable body 56, the movable body spring 57 and the centrifugal pin 58 are mainly used to identify the forward overload. The centrifugal pin 58 is arranged in several radial blind holes symmetrically distributed along the radial direction of the movable body 56. The centrifugal pin 58 is subjected to the centrifugal force generated by the rotation of the projectile so that its outer end is close to the inner wall of the shell 1. When the projectile is flying in the outer ballistic process and the abnormal "forward" overload caused by the nutation angle instantaneously approaching zero causes the movable body 56 to move unexpectedly in the axial direction, the friction force generated by the centrifugal pin 58 and the inner wall of the shell 1 and the resistance of the movable body spring 57 jointly resist the forward inertia force generated by the abnormal "forward" overload, preventing the movable body 56 from moving forward and accidentally releasing the first ball 55 and then releasing the energy storage needle piercing firing mechanism 4 to cause the fuse to accidentally ignite on the outer ballistics, triggering a ballistic explosion.

[0033] Furthermore, the centrifugal force of the centrifugal pin 58 is used to generate friction to resist the inertial force generated by the abnormal axial overload, which has a ballistic adaptive characteristic, that is, when the projectile speed is high, the rotation speed is also high, the abnormal axial overload and the inertial force generated by it are large, but the friction force generated by the centrifugal force of the centrifugal pin 58 is also large; and when the projectile speed is low, the rotation speed is also low, the abnormal axial overload and the inertial force generated by it are small, and the friction force generated by the centrifugal force of the centrifugal pin 58 is also small. Therefore, the structure and principle of preventing ballistic explosion have little effect on the trigger sensitivity of the fuze.

[0034] Furthermore, the centrifugal pins 58 are symmetrically distributed along the axis of the movable body 56 , without changing the radial eccentricity of the movable body 56 .

[0035] Furthermore, the number of the centrifugal pins 58 is 8.

[0036] Furthermore, two radial blind holes are dug symmetrically along the circumferential plane on the upper side of the movable body 56. The radial eccentricity of the movable body 56 can be made close to zero by adjusting the diameter, depth and position of the two blind holes respectively, thereby basically eliminating the forward overload peak caused by the nutation angle instantaneously approaching zero during the projectile's outer ballistic flight.

[0037] Furthermore, the energy storage needle piercing ignition mechanism 4 includes a support 3, a firing pin 41 and a firing pin spring 42. When the firing pin 41 is released, the firing pin 41 is resisted by the firing pin spring 42 and overcomes the remaining forward overload to move downward, piercing the needle detonator (not in this module, not shown in the figure) arranged below the firing pin 41, so that the fuze completes the predetermined unloading ignition effect.

[0038] Furthermore, the centrifugal safety mechanism 6 of the forward overload and unload identification mechanism includes a centrifugal wheel 61, a centrifugal wheel spring 62, a spring plug 63, and a movable body 56. The centrifugal safety mechanism 6 of the forward overload and unload identification mechanism comprises two sets, radially symmetrically arranged along the housing 1, serving as the centrifugal safety mechanism for controlling the forward overload and unload identification mechanism 5 of the stored-energy needle ignition mechanism.

[0039] Furthermore, the centrifugal safety mechanism 6 of the forward overload and unloading identification mechanism each corresponds to its own anti-recovery mechanism. The anti-recovery mechanism 7 of the centrifugal safety mechanism includes a locking plate shaft 71 and a locking plate 71. It is the anti-recovery mechanism of the centrifugal safety mechanism 6 of the forward overload and unloading identification mechanism, and relies on the centrifugal torque generated by the rotating environment to work. When the centrifugal wheel 61 releases the safety of the living body 56, it is locked in the released safety position. Even if the projectile speed decays at the end of the outer trajectory or is subjected to abnormal forward overload during flight, the centrifugal wheel 61 will not be restored to the safety position for the living body 56.

[0040] Furthermore, the designs of the energy storage needle pricking ignition mechanism 4, the unloading identification part in the forward overload and unloading identification mechanism 5 that controls the energy storage needle pricking ignition mechanism, the centrifugal safety mechanism 6 of the forward overload and unloading identification mechanism, and the anti-recovery mechanism 7 of the centrifugal safety mechanism are all mature technologies. Without affecting the original functions, only the internal structure of the living body 56 is changed, a centrifugal pin 58 is added, and the center of mass of the living body 56 is designed to be on its axis by removing the entity through digging a hole, which greatly improves the ability of the fuze inertial ignition module to resist abnormal "forward" overload, and can fundamentally prevent the occurrence of ballistic explosions.

[0041] The difficulty of the present invention lies in accurately identifying the external ballistic environment to which the fuze is subjected, and only improving the internal inertial parts of the fuze inertial ignition module. The friction force generated by the centrifugal inertial force exerted on the centrifugal pin 58 in the external ballistics on the inner wall of the shell is used to offset the inertial force caused by the abnormal "forward surge" overload exerted on the movable body 56 when the nutation angle instantaneously approaches zero, thereby achieving the purpose of limiting the abnormal "forward surge" of the movable body 56. By adjusting the radial eccentricity of the center of mass of the movable body 56 to zero, the abnormal "forward surge" overload value is greatly reduced, the ballistic insurance capability is improved, and the ballistic explosion of the fuze is prevented.

[0042] Combine Figures 1 to 6 The basic principle of the inertial firing module of a rifled artillery fuze capable of preventing ballistic explosion is as follows:

[0043] Normally, the centrifugal pin 58 is arranged in 8 radial blind holes evenly distributed along the circumference of the movable body 56, controlling the forward overload and unloading identification mechanism 5 of the energy storage needle puncture ignition mechanism to be in a safe state, the position of the energy storage needle puncture ignition mechanism 4 is restricted, and the fuze inertia ignition module is in a safe state.

[0044] During firing, the movable body 56 is subjected to recoil and is close to the end cover 2, ensuring that the second ball 54 and the first ball 55 are in place, controlling the forward overload and unloading identification mechanism 5 of the stored energy needle piercing firing mechanism to be in a safe state, and the position of the stored energy needle piercing firing mechanism 4 is restricted. At this time, the fuze is in a safe state.

[0045] During the exterior ballistic flight, the centrifugal pin 58 is thrown out by the centrifugal force, and the top is close to the inner wall of the shell 1. The total friction force generated by the top of the centrifugal pin 58 and the inner wall of the shell 1 is:

[0046]

[0047] Where, F f is the total friction force between the eight centrifugal pins 58 and the inner wall of the housing 1, μ is the friction coefficient between the centrifugal pins 58 and the inner wall of the housing 1, ρ is the material density of the centrifugal pins 58, d is the diameter of the centrifugal pins 58, h is the height of the centrifugal pins 58, is the angular velocity of the projectile, and D is the inner diameter of the shell 1.

[0048] Take a 155mm caliber artillery grenade equipped with an M739A1 fuze as an example. The centrifugal pin 58 is made of tungsten alloy with a density of 17g / cm 3 , diameter d is 4mm, height h is 5mm; the shell 1 material is steel, inner diameter D is 24.74mm; the static friction coefficient between the two is estimated to be 0.3. According to the "Mechanical Environment of Medium and Large Caliber Rotating Projectile Fuze Based on Rigid Body Ballistics Simulation" (Peng Qimeng, Wang Yushi, Xiang Fan, et al. "Journal of Detection and Control", Issue 4, 2023, pp. 37-44), the six-degree-of-freedom rigid body ballistic model of the projectile was established. The law of the projectile rotation angle change obtained by simulation under the conditions of initial velocity 930m / s and firing angle 51° is as follows: Figure 12 The projectile speeds at the initial stage, apex, and landing point of the exterior trajectory were selected to calculate the friction generated by the centrifugal pin 58 and the forward overload it can withstand. The results are as follows:

[0049] In the initial stage of the external trajectory, the projectile's rotational angular velocity is about 1880 rad / s. At this time, the friction force F generated by the top of the eight centrifugal pins 58 and the inner wall of the shell 1 f The friction force F is 112.24 N. f It can offset the forward overload of about 418g acting on the living body 56 with a mass of 26.83g.

[0050] Near the vertex of the outer trajectory, the projectile's rotational angular velocity is about 1700 rad / s. At this time, the friction force F generated by the top of the eight centrifugal pins 58 and the inner wall of the shell 1 is f The friction force F is 91.77 N. f It can offset the forward overload of about 342g acting on the living body 56 with a mass of 26.83g.

[0051] Near the point of impact of the outer trajectory, the projectile's rotational angular velocity is about 1500 rad / s. At this time, the friction force F generated by the top of the eight centrifugal pins 58 and the inner wall of the shell 1 is f The friction force F is 50.86 N. f It can offset the forward overload of about 284g acting on the living body 56 with a mass of 26.83g.

[0052] When the projectile hits the target, the forward thrust generated by the forward inertial overload of the living body 56 is much greater than the friction force F f , the fuze can normally realize the unloading ignition function.

[0053] Combine Figures 7 to 10 The present invention is a rifled artillery fuze inertial firing module principle that can prevent ballistic explosion. The radial eccentricity of the movable body is adjusted as follows:

[0054] For example, a 155mm caliber artillery grenade, equipped with an M739A1 fuze, has an original design mass m of 26.83g, a radial eccentricity r of 0.95mm, a diameter D′ of 24.74mm, and is made of steel with a density ρ′ of 7.85g / cm 3 .

[0055] In order to make the radial eccentricity of the original design of the movable body return to zero, the radial direction of the movable body is opened as follows Figure 8 and Figure 10 Assume that the depth of these two radial blind holes is h', the diameter is d', and the circumferential angle θ between them is 90°. Static equilibrium along the direction of the axis of the section through the center of mass EE, that is, the center of mass of the live impact body returns to zero along the radial direction, must satisfy the following formula:

[0056]

[0057] Wherein: m and r are the original design mass of the movable body 56 and its own radial eccentricity respectively.

[0058] If the depth h′ of the radial blind hole is 3 mm, then the diameter d′ needs to be 6.7 mm, so that the radial eccentricity of the center of mass of the living body 56 can be zero. The two radial blind holes are symmetrically distributed on both sides of the symmetry plane of the living body 56, so that the center of mass position of the living body 56 will not change in the axial direction and perpendicular to the symmetry plane of the living body 56.

[0059] According to the simulation program and simulation parameters of the axial overload mathematical model of the internal components of ballistic fuzes in China and abroad in "Analysis of the Exterior Ballistic Mechanics of Rotating Projectile Fuze and Research on the Influencing Factors of Ballistic Explosion" (Hui Jianhao. Analysis of the Exterior Ballistic Mechanics of Rotating Projectile Fuze and Research on the Influencing Factors of Ballistic Explosion, Nanjing: Nanjing University of Science and Technology, 2024), taking a 155mm caliber artillery grenade equipped with an M739A1 fuze as an example, under the launch conditions of an initial velocity of 930m / s and a firing angle of 51°, the initial nutation angle is taken as 0.03°, and then according to "Measurement of the Center of Mass Position of Complex Shaped Components Based on Three-Dimensional Modeling" (Journal of Ordnance Equipment Engineering, Issue 4, 2016, pp. 66-68), the radial eccentricity of the center of mass of the living body 56 is taken as approximately 0.95mm. Assuming that the radial distance between the center of mass of the living body 56 and the axis of the projectile takes the maximum value, that is, the deviation direction between the center of mass of the living body 56 and the axis of the projectile generated by the assembly is consistent with the eccentricity direction of the living body 56 itself, and the maximum radial eccentricity generated by the assembly is 0.15mm, then before the mass eccentricity of the living body 56 is adjusted, the radial distance between the center of mass of the living body 56 and the axis of the projectile is 1.1mm. At this time, the abnormal axial overload peak value obtained by simulation is about 208g. Figure 13 As shown; after adjusting the mass eccentricity of the living body 56, the radial distance between the center of mass of the living body 56 and the projectile axis is calculated by the Monte Carlo method according to the plane vector dimension chain, and the maximum value is about 0.4mm. At this time, the abnormal peak value of the axial overload obtained by simulation is about 76g, as shown Figure 14 shown.

[0060] Depend on Figure 13 and Figure 14 It can be seen that after adjusting the mass eccentricity of the movable body 56, the abnormal axial overload peak value is reduced by 63.5% compared to before the adjustment. Furthermore, by adding the centrifugal pin 58, the maximum forward overload value that can be resisted is 418g, which is far greater than the abnormal axial overload peak value of 76g in the simulation results. Therefore, the method of the present invention is considered feasible.

[0061] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A rifled artillery fuze inertial firing module capable of preventing ballistic explosion, comprising a housing (1), an end cover (2), a support (3), an energy storage needle piercing firing mechanism (4), a forward overload and unloading identification mechanism (5) for controlling the energy storage needle piercing firing mechanism, a centrifugal safety mechanism (6) for the forward overload and unloading identification mechanism, and an anti-recovery mechanism (7) for the centrifugal safety mechanism, characterized in that: The support (3) is in the shape of a rotating body and is axially arranged in the shell (1). The energy storage needle puncture ignition mechanism (4) is arranged in the axial through hole of the support (3). The forward overload and unloading identification mechanism (5) for controlling the energy storage needle puncture ignition mechanism is arranged in the annular space formed by the outer side of the support (3) and the inner side of the shell (1). The energy storage needle puncture ignition mechanism (4) is controlled by the paired radial through holes in the middle of the support (3) and the second ball (54) therein. The centrifugal safety mechanism (6) and the anti-recovery mechanism (7) of the centrifugal safety mechanism are both arranged below the housing (1) and blocked by the end cover (2). The forward overload and unloading identification mechanism (5) for controlling the energy storage needle puncture firing mechanism comprises a housing (1), an end cover (2), a support (3), a baffle (51), a sliding sleeve (52), a sliding sleeve spring (53), a second ball (54), a first ball (55), a movable body (56), a movable body spring (57) and a centrifugal pin ( 58), wherein the sliding sleeve (52), the sliding sleeve spring (53), the second ball (54), and the first ball (55) are mainly used to identify the unloading environment and control the energy storage needle puncture firing mechanism (4); the shell (1), the movable body (56), the movable body spring (57) and the centrifugal pin (58) are mainly used to identify the forward overload, and the centrifugal pin (58) is set in several radial blind holes symmetrically distributed along the radial direction of the movable body (56). The centrifugal pin (58) is subjected to the centrifugal force generated by the rotation of the projectile to The outer end is in close contact with the inner wall of the shell (1). When the abnormal axial overload caused by the nutation angle instantaneously approaching zero during the external ballistic flight of the projectile causes the movable body (56) to move unexpectedly in the axial direction, the friction force generated by the centrifugal pin (58) and the inner wall of the shell (1) and the resistance of the movable body spring (57) jointly resist the inertial force generated by the abnormal axial overload, preventing the movable body (56) from moving forward and accidentally releasing the first ball (55) and then releasing the stored energy needle firing mechanism (4) to trigger a ballistic explosion.

2. The inertial firing module for rifled artillery fuze capable of preventing ballistic explosion according to claim 1, characterized in that: The centrifugal pins (58) are symmetrically distributed along the axis of the movable body (56) without changing the radial eccentricity of the movable body (56).

3. The inertial firing module for rifled artillery fuze capable of preventing ballistic explosion according to claim 2, characterized in that: The number of the centrifugal pins (58) is 8.

4. The inertial firing module for rifled artillery fuze capable of preventing ballistic explosion according to claim 3, characterized in that: Two radial blind holes are dug symmetrically along the circumferential surface on the upper side of the movable body (56), and the radial eccentricity of the movable body (56) can be made close to zero by adjusting the diameter, depth and position of the two blind holes respectively, thereby greatly reducing the forward overload peak value generated by the nutation angle instantaneously approaching zero during the external ballistic flight of the projectile.

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