Abstract: A device including: a casing; an actuation mass rotatable between a first second positions relative to the casing; a first spring for biasing the actuation mass towards the second position; and a blocking mass rotatable between third fourth positions relative to the casing, a first portion of the blocking mass, while in the third position, is configured to engage with a second portion of the actuation mass to maintain the actuation mass in the first position and to prevent the actuation mass, against the biasing by the spring, from rotating to the second position; wherein upon an acceleration event having an acceleration and duration greater than a predetermined threshold, the blocking mass rotates to the fourth position to release engagement of the first portion of the blocking mass with the second portion of the actuation mass to allow the spring to move the actuation mass to the second position.

Abstract: Explosive cutter assemblies and methods include a liner having a single unitary body, and an explosive charge disposed within the liner. The explosive charge includes a continuous unitary body of explosive material having a first area disposed in association with an inner surface of the liner and a second area extending from the center of the assembly to the first area. A detonator can be used to ignite the second area of explosive material, causing propagation of a detonation to the first area, which in turn causes deformation of the liner and projection of the liner toward a target to form a cut. An adaptor sub having a detonator within can be inserted into the cutter assembly to secure the assembly together, position the detonator in association with the explosive material, and engage a conduit usable to raise and lower the cutter assembly and transmit a detonation signal.

Abstract: A bypass switch for high voltage direct current (HVDC) transmission is provided. The bypass switch includes a housing, a fixed contactor disposed in the housing and electrically connected to a first portion of a HVDC transmission circuit, a movable contactor movably disposed in the housing at a position spaced apart from the fixed contactor and electrically connected to a second portion of the HVDC transmission circuit, an insulation member coupled to a side of the movable contactor, an explosive actuator disposed at one side of the insulation member and exploded according to an electrical signal, and a piston mechanism which is moved by the force of gas generated due to the explosion of the explosive actuator, applies force to move the insulation member, and allows the fixed contactor and movable contactor to be electrically connected to each other.

Abstract: Method and device for mixing and initiating a pyrotechnic charge, comprising at least one coherent porous fuel structure (16) and at least one oxidizer (8). According to the invention, the coherent porous fuel structure (16) and the oxidizer (8) are placed apart in a mixing device (1, 20) to prevent unintentional ignition, and in which the oxidizer (8), in response to the action of a force upon the mixing device (1, 20), for example upon firing of an artillery shell, is transported into the coherent porous fuel structure (16), after which the obtained pyrotechnic charge is initiated after a set time delay.

Abstract: A method of igniting one of a pyrotechnic material and primer during or after an all fire setback acceleration. The method including: positioning a mass element along an inclined surface; biasing the mass element in a direction into the inclined surface such that the mass element traverses the inclined surface upon the all fire setback acceleration against the biasing; drawing the mass element toward one of a pyrotechnic material and primer with the biasing after the mass element traverses the inclined surface. The method can further include delaying the drawing until the mass element experiences a set forward acceleration. The delaying can include drawing the mass element into a delay well after the mass element traverses the inclined surface and drawing the mass element across a delay wedge when the mass element experiences the set forward acceleration.

Abstract: A hand grenade fuze has a firing cap, a delay charge, which can be fired by the firing cap, in a delay charge holder, a detonator, which can be fired by the delay charge, in a detonator holder, and a booster charge, which can be fired by the detonator, for firing a hand grenade explosive charge.

Abstract: A SAFE and ARM mechanism is includes an elongated casing having a first end and a second end. A high-G force firing pin is arranged relatively near to the first end and a low-G force firing pin is arranged relatively near to the second end. A detonator is arranged between the high-G force firing pin and the first end. When a G-force within a first range of magnitudes is applied to the casing along its longitudinal axis, the low-G force firing pin is displaced to strike a portion of the high-G force firing pin, and if a G-force within a second range of magnitudes is applied to the casing along its longitudinal axis, the high-G force firing pin is displaced to strike the detonator. The device may become ARMED in response to a centrifugal force generated by spinning the casing on its longitudinal axis.

Abstract: An ammunition firing device incorporating a firing pin intended to impact a pyrotechnic composition to activate its ignition, wherein said firing pin incorporates a rod that slides when said ammunition is fired through the effect of the firing acceleration from a starting position to a deployed position, able to be locked in said deployed position, said rod being integral with a percussion tip occupying a fixed position in contact with said pyrotechnic composition, said rod being located fully inside said tip in said starting position and protruding from said tip in its deployed position, said device further incorporating a hammer to strike said rod during the impact of said ammunition on a target to cause the ignition of said composition.

Abstract: The present invention provides a self destruction impact fuse for fail-proof detonating a projectile, preferably a low velocity projectile. The present invention further provides a projectile that can be detonated reliably even at low velocity.

Abstract: An inertial igniter including: a housing; a striker mass movable relative to the housing; a biasing element for biasing the striker mass towards a percussion primer; one or more movable members each having one or more stops, the one or more stops having a first position for preventing a portion of the striker mass from striking the percussion primer and a second position allowing the portion of the striker mass to strike the percussion primer; wherein the movable members move the one or more stops to the second position when subjected to a predetermined acceleration profile.

Abstract: Some embodiments of the invention provide a dart that contains an HE payload, two time-delay fuses, one providing a relatively longer delay and the other providing a relatively shorter delay and two triggering mechanisms for triggering the fuses. The first triggering mechanism, which triggers on contact with a mine lid, triggers the relatively shorter time-delay fuse. The second mechanism, which triggers on overburdening exposure to water, sand, or soil, triggers the relatively longer time-delay fuse.

Abstract: A vehicle may include a vehicle body maneuverable onto a near collision course with a target and a plurality of inflatable ballutes which, when inflated, extend generally radially from the vehicle body. A controller may cause the ballutes to be inflated prior to an anticipated time of collision with the target. A plurality of explosive charges may be attached to at least some of the ballutes. A detonation controller may be coupled to the controller and to the plurality of explosive charges.

Abstract: A highly reliable fuse for explosives and armaments is achieved by employing a micro mechanical device that operates to disrupt a relatively low impedance bypass circuit coupled in parallel with a relatively high impedance trigger mechanism. The removal of the electrical bypassing is performed as a result of the movement of the micro mechanical device to enable detonation under prescribed conditions. The electrical bypassing is removed by having at least one low impedance electrical bridge that is part of the bypass circuit break when the micro mechanical device is subjected to prescribed trigger activation forces, which are typically large forces, such as are generated during launch or impact. The micro mechanical device may be a micro-electrical mechanical system (MEMS) device and the bridge is at least one spring that is part of the MEMS device and also part of the bypass circuit.

Abstract: The present invention provides a self destruction impact fuse for fail-proof detonating a projectile, preferably a low velocity projectile. The present invention further provides a projectile that can be detonated reliably even at low velocity.

Abstract: A penetration-capable projectile has a casing and a fuze with a fuze housing lower part. An interface area between the casing of the projectile and the fuze housing lower part is formed with a shape and/or strength modification which prevents the fuze housing lower part from being pushed into the casing on impact with a target that is to be penetrated.

Abstract: An impact fuse includes a body containing a piezoelectric generator positioned on a bracket integral with the body. The piezoelectric generator serving as an anvil. The fuse includes a piston intended to mechanically contact the generator upon impact. The piston receives the impact forces transmitted by a cap. The fuse being characterized in that the piston is slidably fitted within the body and in that it includes plastically deformable means that are interposed between the cap and the body. The means are deformed by cap movement upon impact with a target via piston movement. The plastically deformable means is configured to be deformed in a manner that causes the piston to more gradually exert force on the piezoelectric generator.

Abstract: A pyrotechnic initiation delay device intended in particular to cooperate with a device for firing a pyrotechnic charge of the fuze type, particularly for a hand grenade, having a delay composition located inside a delay column, the latter having a lower end and an upper end, a percussion primer being able to cooperate with the upper part of the delay column, and a striker piston held firmly under the lower end of the delay column and able to move axially in the direction of the element to be struck under the action of an explosive charge cooperating with the lower end of the delay column. The delay column communicates with the explosive charge through a cavity containing plugging means allowing or preventing movement of the striker piston under the effect of the explosive charge.

Abstract: A fuse-less shell (10) with a so-called pyrotechnic impact fuse achieves bore safety and safety in front of the bore by providing a spring-supported ball (43) arranged in a central bore (72) within a valve body (65). The valve body (65) separates an explosive charge (60) at the shell side from an impact-sensitive firing charge (28). The firing charge (28) is disposed within a shell cap (24) and surrounds a projection (30), which acts as an anvil, of the valve body (65).

Abstract: A pyrotechnic initiation delay device intended in particular to cooperate with a device for firing a pyrotechnic charge of the fuze type, particularly for a hand grenade, having a delay composition located inside a delay column, the latter having a lower end and an upper end, a percussion primer being able to cooperate with the upper part of the delay column, and a striker piston held firmly under the lower end of the delay column and able to move axially in the direction of the element to be struck under the action of an explosive charge cooperating with the lower end of the delay column. The delay column communicates with the explosive charge through a cavity containing plugging means allowing or preventing movement of the striker piston under the effect of the explosive charge.

Abstract: In a fuse-less shell (10) with a so-called pyrotechnic impact fuse bore safety and safety in front of the bore are achieved by a spring-supported ball (43) in a central bore (72) in a valve body (65). The valve body (65) separates an explosive charge (60) at the shell side from an impact-sensitive firing charge (28). The firing charge (28) is disposed within a shell cap (24) and surrounds a projection (30), which acts as an anvil, of the valve body (65).

Abstract: A firing pin assembly for mechanically igniting a warhead detonator of a projectile by being accelerated in a forward direction by inertia upon impact, includes a firing pin having a rearward firing pin part and a frontal firing pin part arranged in series with the rearward firing pin part as viewed in the forward direction. The assembly further has a firing pin spring urging the firing pin in a direction opposite to the forward direction, and a mechanical device positioned between the rearward firing pin part and the frontal firing pin part. The mechanical device includes a transmission arrangement for transmitting a forward motion of the rearward firing pin part to the frontal firing pin part with a stepped up transmission ratio whereby a forward motion of the rearward firing pin part through a first distance results in a forward motion of the frontal firing pin part, against the force of the firing pin spring, through a second distance which is greater than the first distance.

Abstract: A projectile includes a pyrotechnical detonation chain arranged to be ignited in response to a launching of the projectile. The chain includes two successive spaced-apart portions that are spaced apart to prevent ignition from being transferred therebetween. One of the portions is movable into contact with the other. A holder imposes a yieldable retaining force (e.g., friction, or shear pin) against the movable portion. That force can be overcome by momentum of the movable portion when the projectile strikes a target, whereupon the movable portion moves into contact with, and ignites, the other portion.

Abstract: A discriminating deceleration sensing electrical switch assembly is enclosed within a munitions projectile for providing an electrical circuit path between a pair of electrical contacts upon deceleration of the projectile being greater than a selected deceleration threshold value. The discriminating deceleration electrical switch assembly includes a switch support having a bore hole for holding a spherical mass or ball. A tactile dome switch or snap switch is juxtaposed between an electrical contact assembly, including a pair of electrically conductive surface regions, and the spherical mass. The components are arranged along the munitions firing axis such that, upon sufficient deceleration along the firing axis, a force acting on the spherical mass will cause the dome switch to deform and contact the conductive surface regions to provide switch closure.

Abstract: This invention relates to a gas generator for a seat belt retracting power generating device to supply power to an emergency retracting device of a seat belt retractor, and aims to reliably ignite an ignition agent and a driving agent by concentrating flames into a small-diameter passage when a primer is ignited, quickly supplying heat to a gas generating agent chamber, and preventing the ignition agent and driving agent within the gas generating agent chamber from being damped.

Abstract: Accommodated within a trigger casing are a firing pin arranged movably toward a detonator, an inertia body formed of a permanent magnet and defining along a central axis thereof a through-hole through which the pin extends freely, and a cylindrical permanent magnet having an inner diameter greater than an outer diameter of the body. A ring-shaped non-magnetic weight is also accommodated within the casing in such a way that the weight is arranged on a side opposite to the detonator with the body located between them. When a deceleration or acceleration of at least a predetermined value occurs, the body and the weight together move toward the detonator against magnetic repulsion between the magnet and the body. The inertia body then moves toward the detonator through an opening of a cylindrical permanent magnet under magnetic attraction between the magnet and the body, thereby causing the firing pin to move toward the detonator.

Abstract: A trigger device is provided with a firing pin made of a non-magnetic material and arranged movably toward a detonator, an inertia body formed of a permanent magnet and arranged movably toward the detonator, and a cylindrical permanent magnet having an inner diameter greater than an outer diameter of the inertia body. The firing pin extends freely through the inertia body. When an acceleration acting on the inertia body exceeds repulsion between the inertia body and the cylindrical permanent magnet, the inertia body is caused to move toward the detonator through a cavity of the cylindrical permanent magnet so that the firing pin strikes and fires the detonator. An attracting disk made of a magnetic material is arranged in close contact with a detonator-side magnetic pole surface of the cylindrical permanent magnet so that attraction for the inertia body is increased.

Abstract: A starting device (21, 121, 41) for actuating a gas generator (8) by striking a detonator (10) in response to an acceleration of a predetermined level or more. The starting device includes a firing pin (22), an inertial mass (23), an annular permanent magnet (24) and an erroneous-actuation preventing mechanism (9, 109, 42). The firing pin (22) is capable of igniting the detonator (10) by moving toward and colliding against the detonator (10). The inertial mass (23) is made of a cylindrical permanent magnet for supplying kinetic energy to the firing pin (22). The annular permanent magnet (24) has an inside diameter larger than an outside diameter of the inertial mass (23). The erroneous-actuation preventing mechanism (9,109, 42) prevents the erroneous actuation of the starting device (21, 121, 41). The erroneous-actuation preventing mechanism (9,109, 42) includes a restricting member for selectively setting the inertial mass (23) in a nonmovable state and in a movable state.

Abstract: Propellant formulations are provided which include non-toxic burn rate modifiers. In order to produce a usable propellant formulation, it is necessary to control the burn rate of the propellant. Failure to adequately control the propellant burn rate often results in unacceptable performance of the propellant. For example, during the operation of a rocket motor, or similar device which contains a propellant, the propellant may produce operating pressures which are too high or too low for the intended purpose of the device.It has often been the practice to add lead to rocket motor propellants in order to modify the burn rate and to maintain the burn rate within acceptable parameters. Lead, however, is known to be toxic and a pollutant. Accordingly, it is desirable to replace the lead in the formulation. It has been found herein that bismuth trioxide is capable of modifying the burn rate of propellants without resorting to lead as a burn rate additive.

Abstract: A method and an arrangement to determine the lowest speed at which an activating pin activates a detonator, this being achieved by a hydraulic medium, the viscous property of which is used to control the transfer of energy from the activating pin to the detonator.

Abstract: A warhead which may be integrated, for example, in a bazooka, is capable of shooting through a wall protecting an enemy. For that purpose, a tandem charge includes a hollow charge which produces in the wall a firing passage for a follow-up charge. The follow-up charge is in the form of a fragmentation projectile which produces fragments behind the wall.

Abstract: A powered canopy breaker attached to an ejection seat, that fractures a canopy when the seat is ejected. The breaker has a piston that is operatively connected to an explosive cartridge. When the seat is ejected, the piston engages the canopy, pushing the piston a predetermined distance until the cartridge is detonated. The detonated cartridge thrusts the piston back, fracturing the canopy.

Abstract: The invention relates to an impact fuse (2) having fore-bore safety for a projectile (1), comprising a percussion needle (3) stationary on the fuse and an impact body (4) containing a percussion cap (5) and supported slidingly in the direction of flight, as well as a race for a blocking ball (23) between the impact body and the inner wall of the projectile casing. Which, upon premature impact on an obstacle, is jammed in its race (22) between a shoulder (18, 19, 20) on the inner wall of the casing and a ramp (17) of a groove (14, 15, 16) on the impact body (4), thereby preventing detonation. In order to allow for adjustment of predefined distances for the fore-bore safety, the invention proposes giving the race (22) for the blocking ball (23) a stepped design so that the blocking ball (23) can be jammed at several places within the fuse (2) between shoulders (18, 19, 20) and ramps (17) of different grooves (14, 15, 16).

Abstract: A crash sensor for automobiles of the type including a ball moving against viscous damping in a closed cylinder for releasing a firing pin for initiating a pyrotechnic sequence has an improved release mechanism. When the ball moves a predetermined distance from its normal or resting position during an automobile crash it initiates a cascade of releases of increasingly larger and more powerful snap disks. The firing pin is mounted on and driven by the largest snap disk.

Abstract: In an armor piercing explosive shell of the kind which comprises a hollow charge and an impact contact member placed in the nose cone of the shell to provide electrical contact for initiation of the hollow charge upon impact of the shell against the target, the nose cone of the shell is provided with a reinforced tip for mechanical penetration of the active armor and the impact contact member does not extend all the way to the tip but positioned behind an inner shoulder made in the wall of the nose cone to improve the penetrative performance of the shell against targets protected by active armor.

Abstract: A projectile for a darting gun, comprising a front head housing a front ignition plunger arranged for axial rearward movement when the tip of the projectile strikes a target, the ignition plunger communicating with a rearwardly extending striker means which in an uninfluenced position of the ignition plunger terminates at a first predetermined distance from an ignition time delay element, the ignition time element when triggered by the striker means being arranged to fire a detonator which in turn detonates a main charge arranged in a tubular body attached to the rear of the front head, a safeguarding means which can be influenced by an outer mechanical force, the safeguarding means in a first position holding the ignition time delay element at a second predetermined distance from the detonator, and in a second position allowing the ignition time delay element to travel the second predetermined distance so as to be brought in close enough communication with the detonator for the detonation thereof when said p

Abstract: A projectile and method of making it having a forward end portion which comprises a hollow, metallic nose portion (1) containing a charge (3) adapted to detonate by impact against a target without the use of a fuse. In order to achieve safeguard against initiation when the impact velocity is low the cavity in the nose portion, in a distance from the forwardmost part thereof, is covered by a liner (4) of a softer material than the metal of the nose portion. The liner may be of plastic material.

Abstract: A projectile 10 with a shaped charge warhead 27 and a nose mounted contact fuze 30. A precursor shaped charge 56 and liner 48 are mounted in the base 38 of fuze 30. When a target 64 is impacted by the projectile 10, a precursor shaped charge jet is produced by charge 56 and liner 48 which forms a passage 66 through fuze 30 substantially free of debris from the fuze 30 through which the warhead shaped charge jet 62 passes.

Abstract: An armor piercing explosive shell comprises a hollow charge and an impact contact member placed in the nose cone of the shell and arranged to provide electrical contact for initiation of the hollow charge upon impact of the shell against the target. To improve the penetrative performance of the shell against targets protected by active armor the nose cone of the shell is provided with a reinforced tip for mechanical penetration of the active armor and the impact contact member does not extend all the way to the tip of the shell so that upon impact of the shell against the active armor contact is obtained only after the reinforced tip has penetrated the active armor.

Abstract: An initiating device which employs discardable arming members is disclosed. The design qualifies as a low cost, responsive, impact initiating system for a practice projectile. The method is embodied in a sub-caliber flight projectile as part of a mortar training device.

Abstract: In a fuse for projectiles, a timing ring is mounted rotatably around the longitudinal axis of the fuse, whereby the ignition time or the ignition delay time may be set. To resist rotation of the set timing ring, the timing ring is secured by means of a friction system comprising a friction ring with a friction nut abutting against it. By screwing-down the friction nut, a frustoconical outer surface of the friction nut bears against a frustoconical inner surface of the friction ring to increase the resistance to rotation of the friction ring and thus the timing ring.

Abstract: An acceleration resistant pyrotechnic delay unit delays the ignition of a warhead subjected to high acceleration on launch and high deceleration on impact. The delay unit includes a delay cup housing a pyrotechnic train. The delay cup has a primer cavity a delay cavity and a detonator cavity. A frusto-conical passage extends between the primer cavity and the delay cavity, with the small diameter end opening into the delay cavity. Primer, delay and detonator components of the pyrotechnic train fill the respective cavities in the delay cup. The various components of the train are well supported on all surfaces to prevent fracture due to high acceleration and deceleration.

Abstract: A rotational projectile having a hollow, metallic nose portion (1) containing a charge adapted to detonate by impact against a target without the use of a fuse, whereby the nose portion, rearwardly of either a detonatable charge (2) or a component of such a charge, contains a second component (3) situated in an axially through-going and forwardly diverging channel (5) in a non-metallic insert (4) in the nose portion (1).

Abstract: Device and method for initiating an explosive charge, for example in an aircraft canopy jettisoning system. The initiator has an operating handle which is swung from a safe position to an armed position and then pushed to move a slide and actuate a firing mechanism. The device has a low profile and can be used in applications where space is limited.

Abstract: A fuze of the type used in a rifle grenade assembly with a striker, a rotor nd a rotor lock includes one or more improvements. One pertains to the striker to prevent it from reaching a detonator-striking forward position more than once. Once it advances to the forward position it is locked in it by a spring biased locking pin. Other improvements relate to the release of the rotor by the rotor lock. The rotor remains locked, i.e. in the disarmed state even after intentional launching. It is released to assume the armed state only when the launched assembly accelerates at a certain rate toward the target.

Abstract: A void-sensing fuze whose initiation is deferred until after impact forces have terminated. A safety device safeties the fuze until after the ordnance has fired. Thereafter, upon impact the fuze is committed to fire, but fires only after impact forces have terminated.

Abstract: A hollow pivot pin, with an exposed primer at its side, holds boron potassium nitrate pellets 78 for igniting a flare. A spring-loaded firing pin mechanism is attached radially to the pivot pin and is swung about it by a parachute lanyard. When the firing pin becomes aligned with the primer charge, the firing pin is released and fires the charge.

Abstract: On impact the primer (37) is struck by the point (33) and transmits the ignition to an explosive column (14) located in the hollow nose (4). The splinters from a metal closing piece (17) are then thrown violently into an empty duct (19) located along the center line of the high-explosive filling (23, 24) made of stabilized secondary explosive material. When the projectile has been fired it is driven in rotation in order to stabilize it and the bolt (27) subjected to centrifugal force frees the way along the duct (19). The splinters from piece (17) can therefore travel through the duct (19) and strike the ignition booster (22) which is also made of stabilized secondary explosive material. The hollow charge is formed by the conical piece (11).A highly effective projectile is produced having great operational safety.

Abstract: An improved construction for a percussion fuse. The fuse function has a firing pin rigidly mounted in an ignition head an adapted to coact with a percussion cap mounted in an impact member. This impact member is securedly maintained in a first position by means of at least one blocking sphere which is partially mounted in an annular groove of the impact member and partially mounted in a bore of the cylindrical forward portion of the percussion fuse body. A movable inertial sphere is disposed in a chamber between the impact member and the ignition head. In order to improve the fail-safety there is mounted in this chamber a housing between the impact member and ignition head which is coaxially movable with respect to the firing pin.

Abstract: The fuze comprises a fuze body having a readily crushable nose cone and a thermal initiator, a thermally ignitable flash detonator and a main charge of booster explosive disposed in sequence in the body. The thermal initiator includes a cup having a closed front end and an open rear end closed by a non-metallic, thermally destructive closure. A readily thermally ignitable, incendiary, exothermic chemical material is disposed in the cup, and the cup is fixed in the nose. Rearward of the cup a rotor ball is disposed in the fuze, which rotor ball contains the detonator. A C-spring connects the rotor ball to the fuze body and maintains the rotor ball in an orientation such that the detonator in the rotor ball is out of alignment with the initiator except when the fuze is spinning beyond the gun barrel as when it is connected to a fired projectile. The detonator includes a cup having a closed thermal barrier alignable with the rear end of the initiator cup, and a thermally destructive closure on the opposite end.

Abstract: There is disclosed an initiator assembly for a ballistic missile system to ffect fluid flow of a gas from a source thereof to user equipment disposed in a housing therefor including gas inlet and outlet conduits and comprised of a rotor member journalled for rotation in the housing and formed with a mass of an eccentric weight distribution with respect to the axis of rotation and wherein the rotor is provided with an explosive assembly ignited by a striker assembly activated by launch acceleration of the missile and wherein a drive piston of the explosive assembly fractures a closure element disposed in one of said gas conduits.