Patent Description:
A <NUM> grenade is a type of military weapon that can kill people or destroy light armor and camps by being fired using a grenade launcher. Further, the <NUM> grenade was developed in the United States during the Vietnam War, and has been widely used in many countries in recognition of the great effectiveness thereof after being used in wars.

However, when fuse operation conditions are not met, a certain percentage of grenades remains undetonated. Undetonated grenades are disadvantageous not only because the effectiveness thereof in battled is reduced, but also because they are potentially harmful to fellow soldiers, civilians, and even the operator. Accordingly, appropriate handling of the undetonated grenades is significantly important.

That is, a grenade using a mechanical mechanism, in which a normally fired grenade senses a condition such as an impact and then detonates, has been widely used.

However, a detonation method of a mechanical fuse of the related art is not only structurally complicated, but also has a problem of low operational reliability, which results in a lot of undetonated grenades. Therefore, recently, efforts have been continuously made to solve the problem of the undetonated grenades by developing a fuse using an electronic self-destruction method using a reserve battery which is activated by striking the same.

Particularly, when a grenade falls on grass or in the mud and the impact applied thereto is weak, the same may not detonate. Further, generally, a safety device is required to be provided therein in order to prevent detonation thereof within a distance within which safety is required after the grenade is fired in order to protect a person using a grenade launcher and allies thereof. Accordingly, in consideration of two aspects, namely a function as a safety device and a function of self-destruction with reliable operation of the fuse, it is required to secure the safety and to smoothly implement the functions of detonation and self-destruction of the grenade.

<CIT> forms a relevant prior art disclosure.

Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide an electronic self-destructing fuse structure capable of preventing detonation of a fired grenade before the grenade moves a safe distance away and of allowing detonation thereof under predetermined conditions, thereby increasing the reliability of the grenade and preventing the occurrence of undetonated grenades.

In accordance with the present invention, the above and other objects can be accomplished by the provision of an electronic self-destructing fuse structure including a lower plate structure including a first guide hole vertically penetrating therethrough and a first pin inserted into the first guide hole to vertically move, a substrate module disposed at a lower side of the lower plate structure, the substrate module including a first through-hole positioned corresponding to a position of the first pin, the first through-hole having a reserve battery mounted therein to be activated when struck by the first pin, a second through-hole including a first conductive wire formed thereacross and configured to detect a short circuit, a third through-hole including a second conductive wire formed thereacross and configured to detect a short circuit, and an electric detonator mounted at a lower side thereof, the electric detonator outputting, toward a lower side, an electrical detonation signal in response to the short circuit of the second conductive wire and detonating according to the electrical detonation signal, and a first safety structure disposed at a lower side of the substrate module, the first safety structure including a centrifugal force weight configured to be moved outwards from a center by centrifugal force and to short-circuit the first conductive wire, an impact weight configured to ascend and descend by inertia and to short-circuit the second conductive wire, and a first detonator hole formed to allow the electric detonator to be close to a spit-back.

Here, the lower plate structure may further include a second guide hole vertically penetrating therethrough, and a second pin inserted into the second guide hole to vertically move, the substrate module may further include a fourth through-hole configured to pass the second pin therethrough, and the first safety structure may further include a fixing member configured to temporarily fix the centrifugal force weight between the first safety structure and the substrate module and to be released by pressure from the second pin.

Further, the electronic self-destructing fuse structure may further include a second safety structure disposed at a lower side of the first safety structure, the second safety structure including a second detonator hole formed to transmit an explosive force of the electric detonator to the spit-back disposed at a lower side thereof, and an opening and closing unit configured to close the second detonator hole in an initial stage and to open the second detonator hole by centrifugal force.

In addition, the opening and closing unit may include a semi-circular rotor installed in a stacked form between the second detonator hole and the electric detonator and configured to control opening and closing of the second detonator hole, which is a passage through which a detonation pressure caused by detonation of the electric detonator is transmitted to the spit-back, which is booster powder, the rotor including a penetrating portion configured to open the second detonator hole when the rotor rotates by centrifugal force around a rotation shaft formed at an eccentric position away from the center of the grenade on the side of the second detonator hole, the first safety structure may further include a support protrusion configured to protrude toward a lower side of the centrifugal force weight and a fifth through-hole configured to allow the support protrusion to move downwards in a state of penetrating the first safety structure, and the support protrusion fixes the rotor to prevent a movement thereof and is moved in an outward direction by centrifugal force to cause rotation of the rotor.

Further, the rotor may include a gear formed along an outer peripheral surface with respect to the rotation shaft. A weight unit may be formed between the gear and the rotation shaft. The electronic self-destructing fuse structure may further include a conversion gear unit, disposed above the rotor and configured to rotate while being engaged with the gear of the rotor, the conversion gear unit reducing a rotation speed of the rotor, and a speed reduction unit configured to contact the conversion gear unit to reduce a rotation speed of the conversion gear unit.

In addition, the electronic self-destructing fuse structure may further include a cap-shaped upper plate structure configured to cover the lower plate structure from above and to be coupled thereto, the upper plate structure including a first accommodation groove and a second accommodation groove configured to accommodate upper ends of the first pin and the second pin, respectively.

Further, the substrate module may include a second conductive wire provided to extend along an outer rim thereof, and may be configured to have the same effect as a short circuit of the second conductive wire when the substrate module is damaged.

Further, the first conductive wire and the second conductive wire may have high conductivity, but may be thin conductive wires, the first conductive wire and the second conductive wire being formed by wire bonding or wedge bonding.

In addition, the first pin and the second pin may be placed on respective tang springs and mounted thereon.

In addition, the reserve battery may include an electrode formed on an upper portion thereof and configured to protrude from side to side, the electrode having a bottom surface that is electrically connected to the substrate module.

Further, the centrifugal force weight may include a fixing member configured to prevent movement of the centrifugal force weight in a fixed position, a short-circuit protrusion configured to cut the first conductive wire, a fixing protrusion configured to interrupt the impact weight, and a support protrusion configured to interrupt rotation of a rotor.

As is apparent from the above description, an electronic self-destructing fuse structure of the present invention is capable of significantly reducing the rate of occurrence of undetonated grenades through a self-destruction function, thereby greatly reducing damage to allies and particularly to civilians.

Further, according to the present invention, after the grenade is fired, a safety device thereof is released by setback and centrifugal force, and the grenade operates in consideration of a speed change thereof after the safety device is released while ensuring the safety of a soldier operating a grenade launcher and fellow soldiers. Accordingly, the grenade may reliably detonate even upon a small impact in environments such as snow or mud, and may self-destruct through operation of an electronic circuit mounted on a substrate in the event of occurrence of an undetonated grenade, thereby securing the safety and increasing the efficiency of the grenade.

Hereinafter, a self-destructing fuse structure according to the present invention will be described in detail with reference to the accompanying drawings.

<FIG> is an exploded perspective view showing a disassembled state of the self-destructing fuse structure according to the present invention, <FIG> is a perspective view showing the state in which a second pin strikes a connection portion between a fixing member and a centrifugal force weight, <FIG> are top plan views showing the state in which the centrifugal force weight separated from the fixing member through the operation shown in <FIG> is pushed outwards by the rotational force of the grenade to release interruption of an impact weight, and <FIG> are cross-sectional views showing the state in which the centrifugal force weight separated from the fixing member through the operation shown in <FIG> is pushed outwards by the rotational force of the grenade to release the interruption of the impact weight. Further, <FIG> is a view showing the operational state in which the centrifugal force weight pushed outwards in the operation shown in <FIG> short-circuits a first conductive wire, a protrusion that interrupts the impact weight releases the interruption of the impact weight, and, as a result, the released impact weight short-circuits a second conductive wire due to a speed change resulting from a grenade collision, <FIG> showing the state in which the first conductive wire is not short-circuited, <FIG> showing the state in which the centrifugal weight pushed outwards according to the operation shown in <FIG> short-circuits the first conductive wire, and <FIG> showing the state in which the released impact weight short-circuits the second conductive wire by the speed change due to the grenade collision. In addition, <FIG> is a top plan view showing an operational state of an opening and closing unit in which a protrusion formed under one of the two centrifugal force weights separated from the fixing member in the operation shown in <FIG> interrupts the rotation of a lower rotor and is pushed outwards by the rotational force of the grenade to release the interruption of the rotor, whereby, the self-destructing fuse structure according to the present invention becomes capable of rotation.

As shown in <FIG>, the self-destructing fuse structure according to the present invention is largely formed of an upper plate structure <NUM>, a lower plate structure <NUM>, a substrate module <NUM>, a first safety structure <NUM>, and a second safety structure <NUM>.

The upper plate structure <NUM> is a configuration of an upper portion of the lower plate structure <NUM>, that is, of a warhead side, and includes a first accommodation groove <NUM> and a second accommodation groove <NUM> disposed at a location away from the first accommodation groove <NUM>.

The first accommodation groove <NUM> and the second accommodation groove <NUM> include a first pin 11a and a second pin 12a accommodated therein to be described later, and serve to guide vertical movement of the first pin 11a and the second pin 12a. Here, in order to perform a stable coupling operation, two of each of the first pin 11a and the second pin 12a may be provided, that is, they may be provided in pairs. Accordingly, each of the first accommodation groove <NUM> and the second accommodation groove <NUM> may be provided in a pair formed symmetrically with respect to a central portion.

The lower plate structure <NUM> is configured to be coupled to a lower side of the upper plate structure <NUM>, and a plurality of first coupling protrusions <NUM> are formed on a lower surface of the upper plate structure <NUM> along a circumferential direction thereof. Accordingly, the lower plate structure <NUM> includes a first coupling groove <NUM> coupled to the first coupling protrusion <NUM> along the circumferential direction on an upper surface thereof to perform stable coupling therebetween at an accurate position.

The lower plate structure <NUM> includes a first guide hole <NUM> and a second guide hole <NUM> formed to correspond to respective positions of the first accommodation groove <NUM> and the second accommodation groove <NUM> in the upper plate structure <NUM> to which the lower plate structure <NUM> is coupled upwards, and, as such, the first pin 11a and the second pin 12a pass through the first guide hole <NUM> and the second guide hole <NUM>, respectively, thereby achieving a structure movable upwards and downwards.

In this case, the first pin 11a is set to be placed over an upper end of the first guide hole <NUM>, and the second pin 12a is set to be placed over an upper end of the second guide hole <NUM>, respectively. A first tang spring 11b, which is an inertia spring, is provided in the middle of the first guide hole <NUM>, and the first pin 11a is placed on the first tang spring 11b. In the same manner, a second tang spring 12b, which is an inertia spring, is provided in the middle of the second guide hole <NUM>, and the second pin 12a is placed on the second tang spring 12b. In this manner described above, initial setting is performed.

The first tang spring 11b and the second tang spring 12b are configured to prevent any movement of the first pin 11a and the second pin 12a, respectively, along the first guide hole <NUM> and the second guide hole <NUM> due to a weak impact or an external force, and to have a function of allowing the first pin 11a and the second pin 12a to move downwards along the first guide hole <NUM> and the second guide hole <NUM>, respectively, when a grenade is fired and force exceeding an amount specified by setback is applied thereto.

The substrate module <NUM> is a circuit board, which is represented as a PCB, coupled to a lower side of the lower plate structure <NUM>. In order to perform stable coupling therebetween at an accurate position, the lower plate structure <NUM> includes a plurality of second coupling protrusions <NUM> formed on a lower side surface thereof along the circumferential direction thereof, and the substrate module <NUM> includes a plurality of second coupling grooves 20a formed in an upper surface thereof and coupled to the plurality of second coupling protrusions <NUM>.

The substrate module <NUM> is formed of a first through-hole <NUM> corresponding to a position of the first pin 11a, the first through-hole <NUM> being provided to install a reserve battery <NUM> therein, a second through-hole <NUM> having a first conductive wire 23a formed thereacross, a third through-hole <NUM> including a second conductive wire 24a formed thereacross, and a fourth through-hole <NUM> having a size through which an end portion of the second pin 12a passes corresponding to a position of the second pin 12a.

The reserve battery <NUM> is a battery for power supply. In detail, the reserve battery <NUM> is normally in an inactive state in which power is not supplied thereto, and is activated upon application of an impact thereto from the upper first pin 11a, thereby supplying power thereto.

Here, the reserve battery <NUM> is not positioned on the upper side of the substrate module <NUM> but is positioned in the first through-holes <NUM>, whereby a sufficient stroke space between the reserve battery <NUM> and the first pin 11a may be secured, and the first pin 11a may accelerate while passing through the secured space, thereby more strongly striking the reserve battery <NUM>.

<FIG> is a cross-sectional view showing the state in which the first pin 11a strikes the reserve battery <NUM>.

The reserve battery <NUM> is a battery configured to be activated by an external strike applied thereto to generate electricity, and a bottom surface of an electrode protruding from side to side formed on an upper portion of the reserve battery <NUM> is electrically connected to the substrate module <NUM>. Further, since the reserve battery <NUM> may be applied to various products as well as that of Patent Document <CIT> held by the present applicant, a detailed description of the reserve battery <NUM> will be omitted to prevent the gist of the present invention from being obscured.

As described above, since the first pin 11a and the second pin 12a are each symmetrically formed in pairs, the first through-hole <NUM>, the second through-hole <NUM>, the third through-hole <NUM>, and the fourth through-hole <NUM> provided in the substrate module <NUM> are also each symmetrically formed in pairs.

An electric detonator <NUM> is installed at a lower side of the substrate module <NUM> to generate a detonation caused by an electrical signal received through a short circuit of the second conductive wire 24a.

The first safety structure <NUM> is configured to be installed at the lower side of the substrate module <NUM>. In the same manner, in order to perform stable coupling therebetween at an accurate position, the second coupling protrusion <NUM> protruding downwards from the lower plate structure <NUM> is supported by the second coupling groove 20a formed in the substrate module <NUM>, and protrudes further downwards from the second coupling groove 20a to be accommodated in and coupled into a third coupling groove 30a in the first safety structure <NUM>.

The first safety structure <NUM> includes a centrifugal force weight <NUM> disposed therein corresponding to the position of the second through-hole <NUM>, and an impact weight <NUM> disposed therein corresponding to the position of the third through-hole <NUM>. In addition, the first safety structure <NUM> has a first detonator hole <NUM> formed in the center thereof so that the electric detonator <NUM> penetrates the same and approaches a spit-back <NUM> provided at a lower side of the first safety structure <NUM>.

In order to dispose the centrifugal force weight <NUM> and the impact weight <NUM> therein, the first safety structure <NUM> has a centrifugal force weight accommodation groove <NUM> and an impact weight accommodation groove <NUM> for the accommodation of the centrifugal force weight <NUM> and the impact weight <NUM>. The centrifugal force weight accommodation groove <NUM> has a size to allow the centrifugal force weight <NUM> to be moved in a predetermined range by the centrifugal force from the center to the outside.

In addition, the first safety structure <NUM> further includes a reserve battery accommodation groove <NUM> in which a lower portion of the reserve battery <NUM> mounted in the first through-hole <NUM> formed in the circuit board <NUM> is accommodated.

A fixing member 31a, which is configured to temporarily fix the centrifugal force weight <NUM> in an initial stage to prevent movement thereof, is installed outside the centrifugal force weight <NUM>. Further, a V-shaped groove is formed at a connection portion between the centrifugal force weight <NUM> and the fixing member 31a so that the connection portion therebetween may be relatively easily broken, and the fixing member 31a and the centrifugal force weight <NUM> may be separated from each other by the impact applied thereto by the second pin 12a moving through the fourth through-hole <NUM>.

In addition, the centrifugal force weight <NUM> includes a fixing protrusion 31b to fix the impact weight <NUM> installed adjacent thereto at an initial position so that the same does not protrude upwards, and a short-circuit protrusion 31c formed at an upper portion thereof, the short-circuit protrusion 31c passing through the second through-hole <NUM> and protruding from the same to cut the first conductive wire 23a.

In this case, in order to perform a stable operation, two of each of the reserve battery <NUM>, the centrifugal force weight <NUM>, the impact weight <NUM>, the second through-hole <NUM>, and the third through-hole <NUM> are provided, that is, they are provided in pairs, and each pair thereof is formed to be symmetrical with respect to a central portion thereof. Further, a protrusion 31d formed at a lower end of one of the two centrifugal force weights <NUM>, the one centrifugal force weight <NUM> being installed so that a spring <NUM> is compressed by the centrifugal force, interrupts rotation of a rotor <NUM> of the second safety structure <NUM>, and releases the interruption of the rotor <NUM> mounted on the second safety structure <NUM> when pushed toward the circumference by rotation of the grenade. Further, when the rotor <NUM> moves and then the rotation of the grenade stops, the protrusion 31d also serves to prevent the rotor <NUM> from returning back to an initial position thereof due to a restoring force of the compressed spring <NUM>.

The second safety structure <NUM> is coupled to a lower side of the first safety structure <NUM>, a plurality of third coupling protrusions 30b are formed on a lower side surface of the first safety structure <NUM> along a circumference thereof, and a plurality of fourth coupling grooves 40a coupled thereto are formed in an upper side of the second safety structure <NUM>, thereby providing a structure for stable coupling at an accurate position.

The spit-back <NUM> is positioned at a lower side of the second safety structure <NUM>, and a second detonator hole <NUM> is formed in the second safety structure <NUM> so that the electric detonator <NUM> in the spit-back <NUM> is easily ignited. Particularly, as a safety device, an opening and closing unit <NUM> is provided to close the second detonator hole <NUM> in an initial stage and to open the second detonator hole <NUM> for detonation when detonation conditions are satisfied. In addition, the plurality of fourth coupling protrusions <NUM> are formed on the lower side surface of the second safety structure <NUM> along the circumference thereof so as to rotate together with the rotation of the grenade, and the fifth coupling groove <NUM> coupled thereto allows the second safety structure <NUM> to be coupled to the base plate <NUM> of the fuse unit of the grenade.

A spit-back accommodation groove <NUM> is formed in the base plate <NUM> positioned at the lower side of the second safety structure <NUM>, the spit-back <NUM> is positioned in the spit-back accommodation groove <NUM>, and the second detonator hole <NUM> is formed in the lower side of the second safety structure <NUM> so that the electric detonator <NUM> is close to the spit-back <NUM> to be reliably ignited. Particularly, as a safety device, the opening and closing unit <NUM> is provided to close the second detonator hole <NUM> in the initial stage and to open the second detonator hole <NUM> for detonation when the detonation conditions are satisfied.

The opening and closing unit <NUM> is configured to be opened by centrifugal force in consideration of the firing characteristics of the grenade. To this end, the rotor <NUM>, having an area larger than that of the second detonator hole <NUM>, is installed with respect to a rotation shaft 42a eccentric to a side surface of the second detonator hole <NUM> disposed in the center.

Here, a penetrating portion 43a capable of opening the second detonator hole <NUM> during the rotation of the rotor <NUM> is formed in the rotor <NUM>, which is rotatable laterally around the rotation shaft 42a. That is, the rotor <NUM> blocks a space between the second detonator hole <NUM> and the electric detonator <NUM> in an initial stage, and rotates by eccentric centrifugal force around the rotation shaft 42a during the rotation of the grenade so that the penetrating portion 43a is aligned with a position of the second detonator hole <NUM>. Accordingly, the spit-back <NUM> is positionally aligned with the electric detonator <NUM> and mechanically armed so that the flame can be transmitted.

For this operation, the rotor <NUM> is formed so that an opening-and-closing side portion thereof having a large area with respect to the rotation shaft 42a covers the second detonator hole <NUM>. Further, an outer peripheral surface of the opening-and-closing side portion of the rotor <NUM> has a circular arc formed therearound with respect to the first rotation shaft 42a, and the outer peripheral surface having the circular arc forms a gear 43b to be engaged with a first gear unit 45a to be described later. In addition, a relatively heavy weight unit 43c is formed on a rotation side portion opposite the penetrating portion 43a with respect to the rotational shaft 42a, thereby facilitating rotation of the rotor <NUM> by the centrifugal force.

The rotor <NUM> is a safety device configured to prevent the grenade from detonating within distance within which safety is required in an initial stage of grenade firing. Accordingly, the rotor <NUM> is initially fixed to block initial movement thereof, and is mechanically armed after the grenade moves a safe distance away.

To this end, one of the centrifugal force weights <NUM> of the first safety structure <NUM> is used, and the selected centrifugal force weight <NUM> includes a support protrusion 31d, the support protrusion 31d being formed at a lower side of the selected centrifugal force weight <NUM> and protruding downwards to a lower side of the first safety structure <NUM> to contact the rotor <NUM> and prevent rotation thereof. Correspondingly, a fifth through-hole <NUM> is formed in the first safety structure <NUM> so that the support protrusion 31d can move downwards in a state of penetrating the same.

That is, the support protrusion 31d maintains a fixed state so that the rotor <NUM> does not move when the centrifugal force weight <NUM> is in an initial position, and the centrifugal force weight <NUM> moves outwards by centrifugal force to be separated from the rotor <NUM> and to permit rotation of the rotor <NUM>.

In this case, the rotor <NUM> includes a protrusion formed therein, the protrusion being in contact with the centrifugal force weight <NUM> at the initial position, and the spring <NUM> configured to push the centrifugal force weight <NUM> to the center may be formed on the outside of the centrifugal force weight <NUM>, which serves to support the rotor <NUM>.

Here, a speed adjustment unit <NUM> is installed on a side surface of the rotor <NUM> to prevent the rotor <NUM> from being quickly opened and closed and to prevent the grenade from being armed within a distance requiring safety, the speed adjustment unit <NUM> appropriately slowing down the rotation speed of the rotor <NUM>. The speed adjustment unit <NUM> preferably includes a speed reduction unit configured to contact a conversion gear unit <NUM> to reduce the rotation speed of the conversion gear unit <NUM>, the conversion gear unit <NUM> being disposed above the gear 43b of the rotor <NUM> and rotating while being engaged with the gear 43b of the rotor <NUM> to reduce the rotation speed of the rotor <NUM>, the rotor <NUM> including the gear 43b formed on the outer peripheral surface thereof with respect to a rotation shaft of the rotor <NUM> and the weight unit 43c being formed on the opposite side of the gear 43b.

According to the description of the embodiment of the present invention, the spit-back <NUM> is positioned in the spit-back accommodation groove <NUM> in the base plate <NUM> located below the second safety structure <NUM>, and the spit-back <NUM> is detonated by ignition of the upper electric detonator <NUM> when the second detonator hole <NUM> is open.

<FIG> is a view showing the state in which an opening and closing unit according to another embodiment of the present invention is combined with the base plate <NUM>. A modification of the structure described above is made as follows. The penetrating portion 43a, which may communicate with the second detonator hole <NUM> in a straight line when the rotor <NUM> is moved by centrifugal force, includes connection gunpowder <NUM> therein, the connecting gunpowder <NUM> being located between the electric detonator <NUM> and the spit-back <NUM>. After that, the connection gunpowder <NUM> is detonated in a state of overlapping the electric detonator <NUM>. Accordingly, a detonation pressure passes through the second detonator hole <NUM> and ignites the spit-back <NUM> installed below the second safety structure <NUM>.

Next, an operation procedure of the self-destructing fuse structure including the above-described components is described as follows.

First, when the grenade is fired, as shown in <FIG>, strong setback acting as firing propulsion of the grenade presses an action force of the first tang spring 11b, and the first pin 11a, supported by the first tang spring 11b is allowed to move. Next, the first pin 11a moves along the first guide hole <NUM> and strikes the reserve battery <NUM>, whereby the reserve battery <NUM> is activated to generate electricity to supply power to the substrate module <NUM>.

Further, as shown in <FIG> and <FIG>, in the same manner for the first pin 11a, when the grenade is fired, the setback is applied to the second tang spring 12b, and the second pin 12a, supported by the second tang spring 12b, is permitted to move. Next, the second pin 12a moves along the second guide hole <NUM>, moves through the fourth through-hole <NUM>, and strikes the centrifugal force weight <NUM> and the fixing member 31a, whereby the centrifugal force weight <NUM> is separated from the fixing member 31a and the same is allowed to move.

Next, as shown in <FIG>, the centrifugal force weight <NUM> overcomes the action force of an externally mounted spring due to centrifugal force and presses the spring to be pushed outwards along the centrifugal force weight accommodation groove <NUM>. Next, as the centrifugal force weight <NUM> moves outwards, the short-circuit protrusion 31c formed on the centrifugal force weight <NUM> short-circuits the first conductive wire 23a, thereby releasing a safety and preparing for detonation of the electric detonator <NUM>.

In addition, when the fixing protrusion 31b formed on the opposite side of the fixing member 31a of the centrifugal force weight <NUM> releases the interruption of the impact weight <NUM>, the impact weight <NUM> short-circuits the second conductive wire 24a to detonate the electric detonator <NUM> when an impact is applied to the grenade. In this case, the circuit is electronically controlled so that the grenade becomes armed after moving a safe distance away.

In addition, the operating principle of the opening and closing unit <NUM> provided in the second safety structure <NUM> is described as follows.

As shown in <FIG>, when the centrifugal force weight <NUM> moves by the centrifugal force generated during the propulsion of the grenade, the support protrusion 31d, formed below the centrifugal force weight <NUM> and configured to prevent rotation of the rotor <NUM>, moves along the fifth through-hole <NUM>. Next, when the support protrusion 31d is separated from the rotor <NUM>, the fixed state of the rotor <NUM> is released and the opening-and-closing side portion of the rotor <NUM>, having a large area, rotates outwards by receiving centrifugal force around the rotation shaft 42a.

In this case, the gear 43b formed on the outer circumferential surface of the opening-and-closing side portion of the rotor <NUM> is engaged with the conversion gear unit <NUM> including the first gear unit 45a and the second gear unit 45b formed therein to reduce the rotation speed of the rotor <NUM>, and the rotation speed of the rotor <NUM> is appropriately adjusted by the conversion gear unit <NUM> and the speed reduction unit, which is configured to reduce the rotation speed of the conversion gear unit <NUM> by contacting the same. In this state, the second detonator hole <NUM> is open so that the electric detonator <NUM> may detonate the spit-back <NUM> formed at the lower side of the second safety structure <NUM>.

In this manner, the speed adjustment unit reduces the speed at which the rotor <NUM> opens, thereby preventing the situation in which the second detonator hole <NUM> opens and the spit-back <NUM> is detonated while the grenade remains within a distance within which safety is required.

Further, when the grenade hits a target, the impact weight <NUM> passes through the third through-hole <NUM> due to inertia and protrudes upwards to cut and short-circuit the second conductive wire 24a, which is mounted in the third through-hole <NUM>.

Here, when the current generated by the short circuit of the second conductive wire 24a is applied to the electric detonator <NUM> and the same is detonated, the spit-back <NUM> is ignited. After that, a booster in a grenade body catches fire, main gunpowder detonates, and the grenade detonates.

In addition, in order to prepare for the situation in which the impact weight <NUM> fails to cut the second conductive wire 24a even when an impact is applied to the grenade, it is preferable for the substrate module <NUM> to include an additional electronic switch to cause the grenade to self-destruct after the lapse of a time set by a designer, thereby preventing subsequent death caused by the undetonated grenade.

As described above, basically, the electric detonator <NUM> may operate when the second conductive wire 24a is cut by the impact weight <NUM>. However, depending on the impact angle of the grenade, damage to the lower plate structure <NUM> and the substrate module <NUM> and shape deformation thereof may be caused by the upper plate structure <NUM>, and, as such, the impact weight <NUM> may not cut the second conductive wire 24a.

<FIG> is a perspective view showing the configuration of a substrate module according to another embodiment of the present invention, and also showing the configuration in which the second conductive wire 24a is installed so as to extend outside the third through-hole <NUM> so as to immediately detect the above-mentioned damage to the substrate module <NUM>.

Claim 1:
An electronic self-destructing fuse structure comprising:
a lower plate structure (<NUM>) comprising a first guide hole (<NUM>) vertically penetrating therethrough and a first pin (11a) inserted into the first guide hole to vertically move;
a substrate module (<NUM>) disposed at a lower side of the lower plate structure, the substrate module comprising a first through-hole (<NUM>) positioned corresponding to a position of the first pin, the first through-hole having a reserve battery (<NUM>) mounted therein to be activated when struck by the first pin, a second through-hole (<NUM>) comprising a first conductive wire (23a) formed thereacross and configured to detect a short circuit, a third through-hole (<NUM>) comprising a second conductive wire (24a) formed thereacross and configured to detect a short circuit, and an electric detonator (<NUM>) mounted at a lower side thereof, the electric detonator outputting, toward a lower side, an electrical detonation signal in response to the short circuit of the second conductive wire and detonating according to the electrical detonation signal; and
a first safety structure (<NUM>) disposed at a lower side of the substrate module, the first safety structure comprising a centrifugal force weight (<NUM>) configured to be moved outwards from a center by centrifugal force and to short-circuit the first conductive wire, an impact weight (<NUM>) configured to ascend and descend by inertia and to short-circuit the second conductive wire, and a first detonator hole (<NUM>) formed to allow the electric detonator to be close to a spit-back (<NUM>).