阅读说明：本技术 线膛火炮榴弹弹底机械触发引信 (Mechanical trigger fuse at bottom of grenade of line chamber ) 是由 王雨时 黄井钵 于 2021-09-22 设计创作，主要内容包括：本发明公开了一种线膛火炮榴弹弹底机械触发引信,在引信体内包括自上而下同轴布置的传爆管壳、传爆药、加强帽、垫圈、球盖、隔离球、针刺雷管、开口环、球座、击针、弹道簧、击针套、自毁簧、惯性体和打击球,以及偏心布置的离心球。其中隔离球是隔爆件,与针刺雷管共同构成球转子。平时球转子被击针和开口环锁定在隔爆位置,实现冗余保险。击针和开口环分别依靠发射时的后坐和旋转环境解除对球转子的保险。球转子还实现20 m以远的延期解除保险距离。引信具有擦地炸、大着角发火和离心自毁功能,应用于35 mm口径高炮榴弹时,对2 mm厚铝合金靶板垂直命中时能可靠触发。符合GJB373B-2019《引信安全性设计准则》的相关要求。(The invention discloses a mechanical trigger detonator at the bottom of a line-chamber grenade, which comprises a booster shell, a booster, a reinforcing cap, a gasket, a ball cover, an isolating ball, a needle-prick detonator, a split ring, a ball seat, a firing pin, a trajectory spring, a firing sleeve, a self-destruction spring, an inertia body, a firing ball and an eccentric centrifugal ball which are coaxially arranged from top to bottom in a detonator body. The isolation ball is an explosion-proof part and forms a ball rotor together with the needle detonator. At ordinary times, the ball rotor is locked at the explosion-proof position by the firing pin and the split ring, and redundancy insurance is realized. The firing pin and the split ring release the safety of the ball rotor respectively by the recoil and the rotation environment during firing. The ball rotor also achieves a deferred arming distance of 20 m or less. The fuse has the functions of floor wiping, large-attack-angle firing and centrifugal self-destruction, and can be reliably triggered when being applied to 35 mm-caliber antiaircraft grenades and vertically hitting an aluminum alloy target plate with the thickness of 2 mm. Meets the relevant requirements of GJB373B-2019 'fuze safety design criteria'.)

1. The utility model provides a mechanical trigger fuze at bottom of line chamber gun grenade bullet which characterized in that: comprises a booster, a safety and safety relief mechanism, a ballistic spring (13), a firing mechanism and a striking ball (8) which are coaxially arranged from top to bottom in the inner cavity of a fuse body (9); the booster comprises a booster shell (1), a booster charge (2) and a reinforcing cap (3), wherein the booster charge (2) is arranged in the booster shell (1), the booster shell (1) is downward opened, and the opening end is sealed by the reinforcing cap (3); the safety and safety relief mechanism comprises an isolation ball (4), a ball seat (14), a split ring (15), a ball cover (16) and two acupuncture detonators (5), wherein the ball seat (14) and the ball cover (16) jointly form an accommodating and moving chamber of a ball rotor; the isolation ball (4) is a main explosion-proof part, the left side and the right side of the isolation ball are respectively provided with a first blind hole, the two first blind holes are coaxial, the axis of the isolation ball passes through the center of the sphere, each first blind hole is internally provided with a needle detonator (5), the isolation ball (4) is also provided with a second blind hole facing the center of the sphere, and the second blind hole is vertical to the first blind holes; the isolation ball (4) and the needle detonator (5) form a ball rotor, the split ring (15) is a centrifugal safety part of the ball rotor and is clamped outside a crescent groove at the lower end of the isolation ball (4) to realize centrifugal safety of the isolation ball (9); the detonator shell (1) and the ball cover (16) are connected with the inner cavity of the fuze body (9) through threads; the firing mechanism comprises a firing pin (6), a self-destruction spring (7), an inertial body (10), a firing pin sleeve (11) and a plurality of eccentric balls (12) which are coaxially arranged and used for realizing inertia triggering firing or centrifugal self-destruction firing, the inertial body (10) is riveted with the firing pin sleeve (11), a firing pin point of the firing pin (6) upwards extends out of the firing pin sleeve (11) and then is clamped in a second blind hole of the isolation ball (4) to realize recoil insurance for the isolation ball (4), the self-destruction spring (7) is arranged between the bottom surface of the firing pin (6) and the bottom surface of an inner cavity of the inertial body (10), a ballistic spring (13) is sleeved on the outer walls of the firing pin (6) and the firing pin sleeve (11), and two ends of the ballistic spring respectively abut against a ball seat (14) and the inertial body (10).

2. The bobbin mechanical trigger fuze of a line-bore grenade according to claim 1, wherein: the ball seat (14) is provided with a plurality of through holes along the axial direction, is a peephole for observing whether the split ring is neglected and whether the position of the isolation ball (4) is correct in the assembling process, is also an internal pressure release channel of a high-temperature and high-pressure gas product formed by accidental ignition and explosion of the detonator in an explosion-proof state, and is beneficial to improving the explosion-proof safety of the detonator.

3. The bobbin mechanical trigger fuze of a line-bore grenade according to claim 1, wherein: the inner cavity of the fuse body (9) is in a stepped hole shape, the outer part is large, the inner part is small, the step at the innermost end is matched with the inertia body (10) and used for thickening the tool withdrawal groove part of the fuse body (9) so as to improve the strength of the fuse body during launching, target collision and target penetration.

4. The bobbin mechanical trigger fuze of a line-bore grenade according to claim 1, wherein: the striking ball (8) is arranged between the bottom of the fuse body (9) and the inertia body (10), the axial movement of the original striking block sliding mode is replaced by the rolling of the striking ball (8), the friction force is small, the problem that the guide block is short and easy to lock does not exist, the energy loss of inertia forward impact of the inertia forward impact is greatly reduced when the inertia triggering mechanism of the fuse is used for triggering, and the inertia triggering sensitivity of the fuse is improved.

5. The bobbin mechanical trigger fuze of a line-bore grenade according to claim 4, wherein: the striking ball (8) is a standard high-precision tungsten alloy ball to improve the inertia forward-stroke quality and improve the inertia triggering sensitivity of the fuse.

6. The bobbin mechanical trigger fuze of a line-bore grenade according to claim 4, wherein: the hitting ball (8) is a high-density ceramic ball used as a bearing rolling body so as to further reduce the friction force of rolling and sliding, thereby improving the inertia triggering sensitivity of the fuze.

Technical Field

The invention belongs to the technology of mechanical trigger fuses of rotary shells, and particularly relates to a mechanical trigger fuse at the bottom of a grenade of a line chamber.

Background

Small caliber artillery shells are ammunition with a caliber of 20 mm to 40 mm, which are fired by artillery and perform the purposes of killing, blasting, burning or other tactics, and are widely used in land, sea, air and military and other combat troops due to their high maneuverability and high firing speed.

The multi-match warhead mechanical trigger fuse of the small-caliber grenade. Compared with a bullet mechanical trigger fuse, the small-caliber artillery grenade is matched with the bullet bottom mechanical trigger fuse, so that the requirements of explosion suppression, redundancy safety, rain prevention, blunting sensitivity, trigger delay, floor wiping and large-attack-angle ignition on the fuse are favorably met. The multifunctional grenade for the 35 mm antiaircraft gun in switzerland is provided with a mechanical trigger fuse at the bottom of the grenade, but the details of the structure are not detailed. AOP-8 NATO FUZE CHARACTERISTICS DATA discloses a mechanical trigger FUZE with a bullet bottom of type DM821 in Germany for MK35 type 35 mm caliber antiaircraft cannon DM31 type grenades. The fuse adopts a ball rotor explosion-proof mechanism, a soft belt delay relief mechanism and a centrifugal plate self-destruction mechanism. The whole fuze has about 37 constituent units without considering the traction tube attached to the bottom, and the structure is complex, so the cost is difficult to control, and the reliability is difficult to ensure.

Disclosure of Invention

The invention aims to provide a fuse triggered by a chamber grenade bottom mechanism, which improves the reliability of the fuse and can greatly reduce the cost.

The technical solution for realizing the purpose of the invention is as follows: a mechanical trigger detonator at the bottom of a grenade of a line-chamber artillery comprises a booster shell, booster powder, a reinforcing cap, an isolating ball, a needle-prick detonator, a firing pin, a self-destruction spring, a striking ball, a detonator body, an inertia body, a striking needle sleeve, a centrifugal ball, a trajectory spring, a ball seat, a split ring, a ball cover and a gasket which are coaxially arranged. Wherein two identical needle-punched detonators are loaded with an isolation ball to form a ball rotor. The isolation ball is used as an explosion-proof part to enable the detonator to be in an explosion-proof state at ordinary times, and the ball rotor achieves a delayed safety release function after the fuse safety mechanism releases the safety, so that the acupuncture detonator is aligned to the detonating tube only when the fuse flies out of a muzzle safety distance, and the ordinary and launching safety is ensured. The isolation ball, the two needle-punched detonators, the ball seat, the split ring and the ball cover form a safety and safety relief mechanism. Wherein the booster shell, the booster charge, the reinforcing cap and the gasket form the booster. The firing pin, the self-destruction spring, the inertia body, the firing pin sleeve and the centrifugal ball form a firing mechanism, the firing mechanism is coaxially arranged at the rear end of the safety and safety relief mechanism, and one safety for the ball rotor, namely the recoil safety, is realized. The centrifugal safety mechanism (piece) is a split ring and is clamped outside the crescent groove at the lower end of the isolation ball, so that another safety for the ball rotor is realized.

Compared with the prior art, the invention has the remarkable advantages that: (1) the soft belt with poor production manufacturability is cancelled, the related design requirements of the fuze safety design criterion are comprehensively met by fewer parts under the condition of smaller space constraint, and the fuze safety design criterion specifically comprises explosion-proof safety, redundant insurance, delayed release insurance and the like, and the fuze safety protection device is simple in structure, high in reliability and low in cost.

(2) A plurality of axial through holes are uniformly distributed on the ball seat on the circumference deviating from the central axis, so that the effect of observing whether the split ring is neglected to be installed during fuse assembly can be achieved, and the effects of releasing the pressure of the fuse inner cavity and improving the explosion-proof safety can be achieved.

(3) A hitting ball part is added in the conical socket of the inertial body at the bottom of the fuze body, so that the fuze triggering sensitivity is greatly improved.

Drawings

Fig. 1 is a schematic structural diagram of a mechanical trigger fuse at the bottom of a line-chamber grenade shell of the invention.

In the figure: the explosive shell comprises an explosive shell 1, an explosive 2, a reinforcing cap 3, an isolation ball 4, a needle-prick detonator 5, a firing pin 6, a self-destruction spring 7, a striking ball 8, a fuse body 9, an inertia body 10, a firing pin sleeve 11, a centrifugal ball 12, a ballistic spring 13, a ball seat 14, a split ring 15, a ball cover 16 and a gasket 17 which are coaxially arranged. Two identical needle detonators 5 are filled with an isolation ball to form a ball rotor, the isolation ball is used as an explosion-proof piece to enable the detonators to be in an explosion-proof state at ordinary times, the ball rotor achieves a delay safety-removing function after fuse safety mechanisms are removed, and the needle detonators 5 are aligned to a booster tube only when the fuses are out of the safe distance of a muzzle, so that the safety at ordinary times and the launching safety are guaranteed. The booster comprises a booster shell 1, a booster charge 2, a reinforcing cap 3 and a gasket 17. The ignition mechanism comprises a firing pin 6, a self-destruction spring 7, an inertial body 10, a firing pin sleeve 11 and a centrifugal ball 12, and is coaxially arranged at the rear end of the explosion-proof mechanism, so that one safety of the ball rotor, namely a recoil safety, is realized. The centrifugal safety machine component is an open ring and is clamped outside a crescent groove at the lower end of the isolation ball, so that another safety to the ball rotor is realized.

Detailed Description

The present invention is described in further detail below with reference to the attached drawing figures.

Referring to fig. 1, the mechanical trigger fuse at the bottom of a grenade of a line-chamber artillery sequentially comprises a detonating tube, a safety and safety relief mechanism, a gasket 17, a ballistic spring 13, an ignition mechanism and a striking ball 8 which are coaxially arranged in an inner cavity of a fuse body 9 from top to bottom.

The booster comprises a booster shell 1 with a downward opening, a booster charge 2 pressed in the booster shell 1, a reinforcing cap 3 for sealing the booster shell 1 and the booster charge 2, and a gasket 17 for adjusting the vacancy depth of the reinforcing cap 3 relative to the booster shell 1. The booster is black-14 booster. The upper end surface of the booster is the upper end surface of the booster shell 1 and is basically flush with the annular surface of the upper end surface of the fuse body 9. As the output end of the fuse, the main charge of the projectile and the powder surface adjusting paper pad in the projectile are arranged above the booster tube. The booster is connected with the inner cavity of the fuse body 9 by the external thread of the outer wall of the booster shell 1.

The firing mechanism belongs to a needle-prick firing mechanism and comprises a firing pin 6, a self-destruction spring 7, an inertial body 10, a firing pin sleeve 11 and 6 centrifugal balls 12, and the firing mechanism is coaxially arranged at the bottom of an inner cavity hole of a fuse body 9 and is positioned below a safety and safety relief mechanism. With 6 centrifugal balls 12 off-axis. The primary explosive element that is matched to the firing mechanism is a needle detonator 5 in the isolation ball 4. The ignition mechanism can realize the functions of inertia triggering ignition and centrifugal self-destruction ignition. The inertia body 10 is riveted with the firing pin sleeve 11 together and contains the firing pin 6, the self-destruction spring 7 and the 6 centrifugal balls 12 to form an ignition module component, so that assembly and quality monitoring are facilitated, the firing pin tip of the firing pin 6 extends upwards from the firing pin sleeve 11 and then is clamped in a second blind hole of the isolation ball 4, and the recoil safety of the isolation ball 4 is realized at the same time, the self-destruction spring 7 is arranged between the bottom surface of the firing pin 6 and the bottom surface of the inner cavity of the inertia body 10, the ballistic spring 13 is sleeved on the outer walls of the firing pin 6 and the firing pin sleeve 11, and two ends of the ballistic spring respectively support the ball seat 14 and the inertia body 10. The outer diameter of the inertial body 10 is matched with the bore diameter of the inner cavity of the fuze body 9.

The safety and safety relief mechanism is positioned below the booster, and comprises an isolation ball 4 (which is a main explosion-proof part), two acupuncture detonators 5, a ball seat 14, a split ring 15 and a ball cover 16, wherein the two acupuncture detonators 5 are filled with the isolation ball 4 to form a ball rotor. The ball seat 14 and the ball cover 16 are pressed together to form a chamber for receiving and moving the ball rotor, and also form a safety and arming mechanism module component for facilitating assembly and assembly quality monitoring. The isolation ball 4 is a round ball with an incomplete outline, and a second blind hole and a crescent groove are arranged at the lower end of the isolation ball around the axis of the fuse. The split ring 15 is an elliptical ring with an opening at one end, is a centrifugal safety mechanism, and is clamped into a crescent notch groove at the lower end of the isolation ball 4 to realize centrifugal safety of the ball rotor. The firing pin 6 of the ignition mechanism is usually inserted into the second blind hole at the lower end of the isolation ball 4, so that the backseat safety of the ball rotor is realized, and the centrifugal safety of the split ring 15 of the isolation ball 4 and the backseat safety of the firing pin 6 form the redundant safety of the fuze. Usually, the separation ball 4 is locked by the split ring 15 and the firing pin 6 in an explosion-proof state, namely, the axis of the detonator 5 on the separation ball 4 is deflected by 90 degrees with the axis of the booster tube and the axis of the firing pin 6. The outer circle of the spherical cover 16 is provided with an external thread which is the same as that of the booster shell 1 and is connected with the internal thread of the detonator body 9, so that the requirement on the explosion-proof state and the connection strength of the detonator structure when a projectile penetrates a target is met. The lower end face of the ball seat 14 abuts against the ring platform of the fuse inner cavity to realize axial positioning. The ball seat 14 is uniformly provided with a plurality of through holes along the axial direction on the circumference deviated from the center, is a peephole used for observing whether the split ring 15 is neglected and whether the position of the isolation ball 4 is correct in the assembling process, is also an internal pressure release channel of a high-temperature and high-pressure gas product formed by accidental ignition and explosion of the detonator 5 in an explosion-proof state, and downwardly introduces the high-temperature and high-pressure gas product into a chamber of an ignition mechanism, thereby being beneficial to improving the explosion-proof safety of the detonator. The interference fit between the ball seat 14 and the ball cover 16 enables the isolation ball 4 to be assembled into an explosion-proof state through the central holes of the ball seat 14 and the ball cover 16 after being assembled, and then the next assembly is carried out, so that the fuse is ensured to be assembled into a safe state, namely a non-safety state.

And a ballistic spring 13 is arranged between the safety and safety release mechanism and the firing mechanism and is used for preventing the firing mechanism on the outer ballistic from moving forwards under the action of crawling force, so that the ballistic spring can strike the needle to fire the needle detonator 5 in the safety and safety release mechanism to cause ballistic explosion.

The center of the bottom surface of the inner cavity of the fuse body 9 is provided with a blind hole, the center of the bottom surface of the inertial body 10 is arched upwards to form a conical socket, a hitting ball 8 is arranged between the blind hole of the fuse body 9 and the conical socket of the inertial body 10, the axial movement of the original hitting block in a sliding mode is replaced by the rolling of the hitting ball 8, the friction force is small, the problem that the guiding is short and the locking is easy to happen does not exist, the energy loss of the inertial forward stroke of the inertial triggering mechanism is greatly reduced when the inertial triggering mechanism of the fuse is used for triggering, and the inertial triggering sensitivity of the fuse is improved. The density and the mass of the impact ball 8 are increased by about 1 time by changing a stainless steel ball into a high-precision tungsten alloy ball (the diameter error is within the range of +/-0.01 mm), so that the inertia forward impact energy is improved, and the inertia triggering sensitivity of the fuse is improved. The impact ball 8 is selected to be used as a bearing rolling body with high density (the density is 5.8 g/cm)³Above) the ceramic ball, the friction force of rolling and sliding can be reduced, thereby improving the inertia trigger sensitivity of the fuze.

The inner cavity of the fuse body 9 is in a stepped hole shape, the outer part is large, the inner part is small, the step at the innermost end is matched with the inertia body 10 and used for thickening the tool withdrawal groove part of the fuse body 9, and therefore the strength of the fuse body in launching, target collision and target penetration is improved.

In the service processing stage, the credible impact and vibration, including falling and transportation vibration and the like, specified by GJB573B fuze and fuze part environment and performance test method do not cause the fuze to change the factory state. The fuze is structurally strong enough to withstand the drop impact of an indirect collision without jeopardizing reliability and safety. The direct collision caused by the naked falling of the height of 1.5 m does not reduce the safety of the fuse, and can still ensure the use safety including the launching safety. The self-destruction spring 7 under the firing pin 6 in the detonator ignition mechanism is also a safety spring of the recoil safety mechanism. Even if the most unfavorable 1.5 m high fuse bottom falls down, the self-destruction spring 7 can ensure that the front end of the firing pin 6 is always inserted into the blind hole of the isolation ball 4, and the isolation ball is in an explosion-proof state. The split ring 15 is always in the safety position, and the isolation ball 4 can still be clamped and cannot rotate even if the split ring is accidentally dropped and rolled without being opened, so that the split ring is in an explosion-proof state. At this time, even if the pricked detonator 5 (any one or two of the pricked detonators) in the fuze is accidentally ignited and exploded, the safety and safety release mechanism (explosion-proof mechanism) can ensure that the fuze cannot generate dangerous fragments outwards, and the booster tube cannot be detonated, namely, the fuze cannot be accidentally ignited, and the safety in a service processing stage, a loading stage, an in-bore movement stage and a muzzle safety distance can be ensured.

When the projectile is shot in the chamber, the strength of the bottom of the fuse body 9 is enough, and the fuse body is not damaged or deformed.

At the early stage of the movement of the projectile in the bore, under the action of recoil force, the striker 6 compresses the self-destruction spring 7 to move downwards, the striker 6 does not limit the movement of the isolation ball 4, namely the ball rotor any more, and the recoil insurance of the ball rotor is relieved. And the lower end surface of the split ring 15 is pressed against the upper end surface of the ball seat 14 by the recoil force. At this time, the rotating speed of the shot is low, and the semi-ring centrifugal torque of the split ring is not enough to overcome the friction torque generated by the recoil of the end surface, so that the split ring 5 cannot be opened.

When the projectile moves in the bore to approach the muzzle, the recoil is gradually reduced, and the rotating speed of the projectile is gradually increased. After a certain critical point, the centrifugal ball 12 is thrown out from the radial transverse hole of the striker 6 under the action of centrifugal force and clamped on the inclined surface (circular truncated cone profile surface, i.e. self-destruction inclined surface) of the opening of the striker sleeve 11 and the cylindrical surface of the inner hole of the inertial body 10. The supporting reaction of the inclined surface of the opening of the striker sleeve 11 to the centrifugal ball 12 acts on the wall of the radial transverse hole on the striker 6, and then the gradually weakened recoil can be compensated to resist the resistance of the self-destruction spring 7. In the process, the striker pin 6 is always in the state of being disengaged from the isolation ball 4, i.e. the isolation ball 4 is completely released. After another critical point in the same period, the split ring 15 overcomes the recoil friction torque and the bending resistance torque of the prefabricated weak part thereof under the action of the semi-ring centrifugal torque thereof, and is opened to be thrown into the ring groove reserved in the inner cavity of the ball cover 16 outwards, so that another safety (centrifugal safety) of the ball rotor is relieved.

Whether the split ring 15 is thrown in the bore or outside the bore to release the safety of the ball rotor, because the friction torque generated by the recoil overload in the bore is larger, the ball rotor can start to rotate only when the recoil overload is obviously reduced at the end of the expiration date when the projectile flies out of the muzzle, and the centrifugal torque of the ball rotor is larger than the friction torque, and the projectile can rotate to the alignment position (20 m for 35 mm caliber grenades) beyond the safety distance of the projectile flying out of the muzzle, namely, the acupuncture detonator 5 at one end of the isolation ball 4 is opposite to the firing pin 6, the acupuncture detonator 5 at the other end is opposite to the booster tube, the axis of the acupuncture detonator 5 is coincident or nearly coincident with the axis of the projectile, and the detonator is in the arming state after the safety is released.

The effective period after the projectile flies out can be affected by crawling overload. Creeping overload may cause the firing module to creep forward causing the firing pin 6 to pierce the detonator 5 in the already aligned spacer ball 4 causing ballistic blow. Although the rotating speed of the projectile is very high, the centrifugal force and the friction force of the ignition module are generally very large, the friction force is far greater than the crawling force, but the centrifugal radius causing the centrifugal force is a random quantity and is inevitably close to 0 or just 0; in addition, the nutation force direction is opposite to the crawling force direction, and can counteract the crawling force to some extent so as to help avoid the ballistic blast, but the nutation force is a periodic force and is also 0 at a certain periodic point, so that the ballistic spring 13 is necessary for preventing the ballistic blast, and the resistance is selected according to the limit crawling overload consideration.

When the shot hits a target or lands (including the situations of large landing angle and small landing angle), the motion of the shot is blocked, the rotating speed begins to attenuate, the striker overcomes the axial component force of the restraint counter force generated by the centrifugal force of the centrifugal ball along the self-destruction inclined plane under the combined action of the front impulse force and the resistance of the self-destruction spring, moves forwards, and punctures the needle-punctured detonator 5. Meanwhile, under the action of forward impulse, the firing module and the striking ball overcome the centrifugal friction force between the inertial body 10 and the inner wall of the fuse body 9 and the resistance force of the ballistic spring 13, and move forward together with the striking pin 6 to pierce the needle-punched detonator 5. Upon firing of the needle detonator 5, which is within the spacer ball 4 but at the other end, is detonated, which in turn detonates the booster charge 2 and the subsequent main charge of the projectile. Because the mass of the ignition module and the striking ball 8 is far larger than that of the striking pin 6 and the centrifugal ball 8, and the axial resistance force generated by the centrifugal ball 8 along the self-destruction inclined plane is larger, the action of inertia triggering ignition is mainly the forward motion of the ignition module and the striking ball 8. The important function of the striking ball 8 is that the front impact force of the striking ball overcomes the static friction force between the outer cylindrical surface of the inertial body 10 and the inner cavity hole wall of the fuze body 9, so that the front impact motion of the striking ball is quickly started. When the device is applied to 35 mm-caliber antiaircraft grenades, the device can be reliably triggered when an aluminum alloy target plate with the thickness of 2 mm is vertically hit.

Under the conditions of large impact angle and small drop angle, theoretically speaking, if the action of the hitting ball 8 is neglected conservatively, the fuse can realize inertia triggering ignition as long as the residual angle or the drop angle of the impact angle of the projectile is larger than the static friction angle between the outer cylindrical surface of the inertial body 10 and the inner cavity hole wall of the fuse body 9. Assuming that the static friction coefficient between the outer cylindrical surface of the inertial body 10 and the inner cavity hole wall of the fuse body 9 is 0.2, the minimum ignition falling angle and the maximum ignition falling angle of the fuse are respectively 11.3 degrees and 78.7 degrees theoretically, and the requirement of most application occasions can be met.

Under the condition that the shot is shot to the air, if the shot cannot hit a target, in the descending arc section of the shot, along with the gradual attenuation of the rotating speed of the shot, the centrifugal force of the centrifugal ball 8 is gradually reduced until the supporting counter force generated by the shot along the self-destruction inclined plane at a certain critical point is not enough to support the resistance of the self-destruction spring 7, then the self-destruction spring 7 pushes the firing pin 6 to move forwards, the firing pin punctures the detonator 5, and the air centrifugal self-destruction is realized.

If the ball rotor fails to rotate for any reason (which is one of the trusted failure modes of the ball rotor mechanism), after the projectile hits the target or the air self-destruction threshold, the firing pin 6 will be reinserted into the blind hole of the spacer ball 4 under the influence of the front thrust of the firing module and the striking ball 8 or the front thrust of the firing pin and its centrifugal ball and/or the resistance of the self-destruction reed 7, and the fuze enters the state of recovering the recoil safety. The explosive treatment safety of the unexploded explosive can be fundamentally ensured.

If the ball rotor has already started the rotation process but has failed to rotate in place for any reason (this case is also one of the trusted failure modes of the ball rotor mechanism), then after the critical point of airborne self-destruction, especially after the projectile hits the target, the point of impact will be damaged to a different extent by hitting the surface of the spacer ball 4, and the fuze enters a self-failure state, which can ensure the explosive handling safety to a certain extent.

The fuse is mechanically triggered at the bottom of the grenade of the line-chamber artillery, meets the relevant requirements of GJB373B-2019 'fuse safety design criteria' standard, and specifically comprises explosion suppression, redundancy insurance, delayed release insurance, application of allowable explosive transfer agents, non-release insurance state guarantee, failure rate of a safety system, manual non-release insurance, self-destruction, self-failure and the like.