The present invention relates to a safety and arming unit for initiation of underwater charges, comprising: a housing; a detonator; an interrupter slidable within the housing from a first position in which a firing chain from the detonator to a charge is interrupted, to a second position, in which the firing chain is complete; a first member configured to cooperate with the housing and the interrupter to form a first interlock, wherein, upon the first member being in a first position, said interlock locks said interrupter in said first position, and upon the first member being in a second position, said interrupter is free to slide relative to said first member; a second member configured to cooperate with the housing and the interrupter to form a second interlock, mechanically independent of said first interlock, wherein, upon the second member being in a first position, the interlock locks said interrupter in said first position, and upon the second member being in a second position, said interrupter is free to slide relative to said second member; and a plurality of electrical switches arranged in series, switchable from a first configuration in which the detonator is electrically isolated from a remote initiation firing system, to a second configuration in which the detonator is in electrical communication with a remote initiation firing system; wherein, upon the first member being in the second position, and the second member being in the second position, the interrupter is slidable from the first position to the second position upon being subjected to an external water pressure of at least a predefined threshold value. Upon the interrupter being in the second position, the interrupter acts on the plurality of electrical switches to switch said plurality of switches to said second configuration.

A fuze for a projectile intended to be fired by a cannon by ignition of a propellant charge using an electric igniter. This fuze is allowed to pass from a safety position to an armed position following the fire by releasing at least two different safeties. This fuze includes a capacitor which is intended to be connected to the electric igniter and which charges during the ignition of the propellant charge, and also a computer which detects the charge of the capacitor in order to allow the arming of the fuze when this charge is greater than or equal to a reference value, the charge of the capacitor constituting a first fire safety.

The invention relates to a method of delaying a mechanism in a firearm and a delay unit for a projectile comprising i) a first and a second pressure chamber (3a, 3b) arranged to receive combustion gases in a firearm via at least one inlet (1a, 1b) arranged to each of said first and second pressure chambers (3a, 3b) following firing of a projectile ii) at least one outlet for transferring the combustion gases (4a, 4b), arranged to each of said first and second pressure chambers (3a, 3b), to a piston chamber in which a displaceable piston (6) is arranged dividing the piston chamber into a compartment (5b) having a volume V.sub.1 upstream the piston (6) and a compartment (5a) having a volume V.sub.2 downstream the piston (6), wherein said at least one outlet (4a, 4b) from the first and second pressure chambers (3a, 3b) are arranged to transfer said combustion gases to said compartments (5a, b) of said piston chamber to provide an overall pressure difference between compartments (5a) and (5b) pressing the piston (6) at an initial idle position downstream whereby the volume V.sub.2 of compartment (5a) is reduced and whereby the piston (6) being pressed downstream towards an end position actuates a function at a predetermined point in time following firing of a firearm.

The present invention relates to a safety and arming unit for initiation of underwater charges, comprising: a housing; a detonator; an interrupter slidable within the housing from a first position in which a firing chain from the detonator to a charge is interrupted, to a second position, in which the firing chain is complete; a first member configured to cooperate with the housing and the interrupter to form a first interlock, wherein, upon the first member being in a first position, said interlock locks said interrupter in said first position, and upon the first member being in a second position, said interrupter is free to slide relative to said first member; a second member configured to cooperate with the housing and the interrupter to form a second interlock, mechanically independent of said first interlock, wherein, upon the second member being in a first position, the interlock locks said interrupter in said first position, and upon the second member being in a second position, said interrupter is free to slide relative to said second member; and a plurality of electrical switches arranged in series, switchable from a first configuration in which the detonator is electrically isolated from a remote initiation firing system, to a second configuration in which the detonator is in electrical communication with a remote initiation firing system; wherein, upon the first member being in the second position, and the second member being in the second position, the interrupter is slidable from the first position to the second position upon being subjected to an external water pressure of at least a predefined threshold value. Upon the interrupter being in the second position, the interrupter acts on the plurality of electrical switches to switch said plurality of switches to said second configuration.

The invention relates to a method of delaying a mechanism in a firearm and a delay unit for a projectile comprising i) a first and a second pressure chamber (3a, 3b) arranged to receive combustion gases in a firearm via at least one inlet (1a, 1b) arranged to each of said first and second pressure chambers (3a, 3b) following firing of a projectile ii) at least one outlet for transferring the combustion gases (4a, 4b), arranged to each of said first and second pressure chambers (3a, 3b), to a piston chamber in which a displaceable piston (6) is arranged dividing the piston chamber into a compartment (5b) having a volume V.sub.1 upstream the piston (6) and a compartment (5a) having a volume V.sub.2 downstream the piston (6), wherein said at least one outlet (4a, 4b) from the first and second pressure chambers (3a, 3b) are arranged to transfer said combustion gases to said compartments (5a, b) of said piston chamber to provide an overall pressure difference between compartments (5a) and (5b) pressing the piston (6) at an initial idle position downstream whereby the volume V.sub.2 of compartment (5a) is reduced and whereby the piston (6) being pressed downstream towards an end position actuates a function at a predetermined point in time following firing of a firearm.

A fuze for a projectile intended to be fired by a cannon by ignition of a propellant charge using an electric igniter. This fuze is allowed to pase from a safety position to an armed position following the fire by releasing at least two different safeties. This fuze includes a capacitor which is intended to be connected to the electric igniter and which charges during the ignition of the propellant charge, and also a computer which detects the charge of the capacitor in order to allow the arming of the fuze when this charge is greater than or equal to a reference value, the charge of the capacitor constituting a first fire safety.

A safety and arming device for a munition is operable to arm and initiate a munition dependent on determining separation from a munition platform, determining detection of free fall of the device for a first time period following separation, initiating a roll manoeuvre of the munition and determining detection of the execution of the roll manoeuvre within a second time period, and generating a munition firing signal, dependent on detection of all of separation, free fall, and the roll manoeuvre.

A grenade firing mechanism (12) includes a body (24) containing a firing pin (20) and a tiring pin actuator mechanism (22). A safety system includes twist to arm collar (70) and a safety interlock (92). The collar is movable between an unarmed position and an armed position and tire safety interlock is movable between a collar locking position, a collar release position and a firing position. When the collar (70) is in the unarmed position and the safety interlock (92) is in the collar locking position, actuation of the firing pin (20) is inhibited and the safety interlock (92) inhibits movement of the collar to the armed position. When, the safety interlock (92) is in the collar release position, the collar (70) is able to be moved between said unarmed and armed positions and actuation of the firing pin is inhibited. When the collar (70) is in the armed position and the -safety interlock (92) is in the firing position, actuation of the firing pin is enabled.

A device for generating power in a gravity dropped munition. The device including: a drum; a cable wound around a drum; a generator for producing electrical energy; a spring configured to convert rotation of the drum to energy as the cable is unwound from the drum; and an intermediate member selectively engaging the drum to the generator; wherein the intermediate member is disengaged from the drum when the cable is being unwound from the drum and the intermediate member is engaged with the generator when the cable is released from the drum to produce power from the generator.

A system for quick arming of a detonation or excitation assembly, wherein the system comprises a first barrier means which, as long as it has not been removed, prevents full activation of an initiation chain of the assembly, and whose removal is dependent on receiving indication from at least one first sensor, and then its removal is reversible in a manner that it will return and once again prevent full activation of an initiation chain, and a second barrier means which also prevents full activation of the initiation chain as long as it has not been removed, and whose removal is dependent on receiving indication from at least one second sensor, and thisfollowing after receiving indication from the first sensor, and removal of the second sensor is irreversible in a manner that leaves the initiation chain executable, and wherein the first and second sensors are independent of one another, and as long as no indication has been received from the second sensor, the first barrier means is returnable to its place in a manner that will return and once again prevent full activation of the initiation chain, and an active protection system utilizing a plurality of those quick arming system for activation of the protection system's interceptors while implementing a method for quick and selective arming of the active protection system's detonation or excitation assemblies.