Abstract: A first end of a conductive spring is embedded in a wall of a large chamber of a piston housing. The spring is held in tension by a second end of the spring being pinned against a bead contact by a trigger pin. The diameter of the piston and a tensile breaking strength of the trigger pin are selected so that the trigger pin is breakable and the tension in the spring is releasable upon the presence of a predetermined pressure difference between a pressure on the contact side of the piston and a pressure on the pinning side of the piston. Release of tension in the spring closes an electrical circuit.

Abstract: A downhole perforating gun switch is located in the sub housing and has first, second and intermediate contacts, with the intermediate contact located between the first and second contacts. In an initial position, the intermediate and second contacts are in contact with each other, while the intermediate and first contacts are out of contact with each other. A thermoplastic plug is positioned between the intermediate and second contacts. A conductive sleeve or enclosure provides the electrical contact between the intermediate and second contacts. When the switch is subjected to detonation effects from the perforating gun, the second contact, the plug, and the intermediate contact are moved toward the first contact, wherein the first and intermediate contacts contact each other and the intermediate and second contacts are out of contact with each other.

Abstract: Methods and apparatus for sensing acceleration according to various aspects of the present invention comprises a non-rigid membrane and a switching latch electrically coupled to the membrane. The membrane is responsive to acceleration forces and is configured to produce a signal as a result of deflections in the membrane caused by acceleration. The signal is transmitted to the switching latch causing a change in state of the switching latch. This change in state allows a second signal to be sent to an activating device such as a squib.

Abstract: An apparatus for the cutting of an electrical conductor has an electrical conductor arranged in a housing, a pyrotechnic drive and a cutting device. After the triggering of the drive, the cutting device enters into engagement with the conductor to cut it.

Abstract: A gas pressure switch is provided for an ignition and safety system for ammunition. The switch includes a housing; a piston actuator within the housing, the piston actuator being displaceable from an idle position to a contacting position by propellant gases of the ammunition during use; at least two contact pins that are attached immovably to the housing; a contacting device operatively associated with the piston actuator and located on a first side of the piston actuator, the first side being opposite a second side on which the propellant gases act during use, the contacting device connecting electrically to the contact pins when the piston actuator is in the contacting position; and a locking pin which holds the piston actuator in the idle position until a predetermined gas pressure is reached and which shears off when the predetermined gas pressure is reached, so that the piston actuator can be displaced into the contacting position.

Abstract: An arming system for a missile which prevents destruction of the missile side of a specified area. The missile may be launched from a submarine, and follow a water-air-trajectory, and includes a variable-range timer acting in conjunction with an impact detection system. The timer drives arming switches to the armed condition after a predetermined time, and then opens the switches after a second predetermined time, which establishes a maximum range for detonation of the missile warhead.

Abstract: A circuit-breaking apparatus is formed of an insulating housing, first and second electrodes located at both ends of the insulating housing, a detonator located in the first electrode, a lead connected to the detonator for supplying an electric current to the detonator when the detonator is actuated, and a conductor disposed in the insulating housing. The conductor includes a fixed portion electrically connected to the first electrode, a circuit-breaking rod having narrow portions at both ends, and a barrel connected to the second electrode and having a cavity. The circuit-breaking rod is coupled to the fixed portion and the barrel through the narrow portions. The barrel has a locking section for locking in the cavity the circuit-breaking rod that has been shifted toward the second electrode due to cutoff of the narrow portions caused by the explosion of the detonator.

Abstract: In well perforating operations, it is necessary to detonate shaped charges suspended in the well. To avoid dangerous detonation at the surface, a pressure responsive mechanism is set to respond to a pressure indicative of operation at a selected depth. This pressure setting arms the detonator in cooperation with an electrical arming mechanism operative in response to a selected current flow at a required voltage for a selected interval.

Abstract: An inertia element within a projectile is displaced to a retracted position y acceleration of the projectile during launch to unblock displacement of a slider to an armed position in response to subsequent pressurization of a projectile flight motor. Safe separation timers are thereby enabled in response to proper launch to delay pressurization of the flight motor and powering of an explosive firing circuit through switches actuated by said displacement of the slider from a safe position to the armed position. The slider is held in its safe position by an electrically grounded shear wire that is ruptured in response to slider displacement thereby removing a power disabling shunt connection to the firing circuit.

Abstract: A safety device for use in low-speed aerodynamic bodies. The pressure conditions at the outer contour of the flying equipment are used for obtaining an arming criterion of a fuse. A slide is movable from a safe to an armed position. In the safe position, slide pickup ports are within the internal contour of the body. In the armed position, the slide pickup ports are exposed to the air stream outside the external contour of the body for creating a pressure difference for arming the fuse.

Abstract: A safe and arm device having a bellows motor-driven rotor bearing a detonr. When the device is in the SAFE condition the detonator is shrouded by an airpot piston extending from one end of a spring secured within the airpot cylinder in the housing. The airpot piston compresses the spring in response to weapon acceleration until the piston fully resides in the airpot cylinder in the device housing. The rotor is thus free to be rotated overriding a detent maintaining the SAFE condition by the action of the bellows motor which is electrically activated. The rotor turns until it reaches the "ARMED" position where the detonator therein is positioned directly in line with weapon's warhead explosive trigger charge in the housing. The rotor is rotationally secured relative to the housing in the "ARMED" position by the action of another detent.

Abstract: A body member has an opening formed therein. A receiving contact is located in the opening of the body member and has an electrical lead connected thereto which extends out of the body member. The receiving contact has a cavity with an opening at one end which faces the plunger end of the body member. An interior contact is located in the cavity of the receiving contact and is electrically insulated therefrom. An electrical lead is connected to the interior contact and extends out of the body member. A moveable plunger including a plunger contact is located in the opening of the plunger end of the body member. The plunger contact has an opening which releasably supports a shuttle contact at a position spaced away from the interior contact. In this position an electrical connection is provided between the receiving contact lead and the plunger contact by way of the receiving contact and the shuttle contact.

Abstract: An arming device for a missile having a rotating tail fin assembly is disclosed. The device includes a distance counter comprising a given length of coiled tape contained within a rotatable drum, the length of the tape being determined by the distance required to be covered by the missile before arming the warhead. The tape is wound onto a shaft driven by the tail fin assembly from the drum which is initially locked to the missile body, and when the tape has been completely wound onto the shaft, the drum is released and is free to rotate through a half-turn to initiate arming of the warhead.

Abstract: A safe and arm device including a sensor-controlled switch arrangement in an electrical series-circuit, which is arranged ahead of a secondary-explosive detonator, especially for a submunition-projectile. The safe and arm device possesses a first switch which is actuatable at the presence of a surrounding air onflow against the submunition carrier in dependence upon a submunition ejecting command; and wherein a second switch is actuatable by the first switch when the submunition-projectile has released itself from its carrier and has implemented a transition into a gliding flight phase searching for a target.

Abstract: The present invention relates to arming methods and devices for firing a submarine weapon.A device according to the present invention comprises a piston connected by a strip to a bistable arming organ. The piston shifts inside a cylindrical body between a first and second chamber. The first chamber accommodates sea water through orifices. The second chamber accommodates sea water through a valve and a cavity which is filled with sodium chloride. The piston is hollow and contains a semi-permeable fitting which is in contact with sea water that is contained inside the first chamber through a bore and ducts, and with the salt saturated solution contained inside the second chamber through channels.

Abstract: An ignition system for projectiles, such as shells, bombs, or rockets is disclosed. The system has a pressure chamber defined by a double-diaphragm switch and a cap of a deformable material. The diaphragm of the double-diaphragm switch, which defines one wall of the pressure chamber, contains one or several perforations, the number and diameter of which depend on the spacing of the diaphragms, the areas thereof and the size of the pressure chamber. The double-diaphragm switch is connected to an electric ignition unit. An electrical circuit is closed only if a projectile housing a percussion fuse and the ignition system impacts on the ground or target after its flight. Any unintended ignition during firing or due to brief impact stress cannot occur.

Abstract: A delayed action switch embodied in a tubular casing adapted to be incorporated in a missile or a guided projectile. For example, the Redeye missile is activated by a soldier who keeps it against his shoulder. As he pulls the trigger, the missile takes off toward a specific target such as a tank, truck or the like, a distance of a few seconds away from the soldier. Should the missile drop near the soldier and explode, the soldier would be killed; but with the delay switch of this invention incorporated in the missile, it would be deactivated before it hits the ground. Consequently, the missile would be a "dud", a non functional device. In general, the switch of our invention includes, in succession within a tubular casing, a priming charge which is ignited when the missile is first propelled into the atmosphere, and which fires an ignition charge which in turn ignites a delay charge.

Abstract: A safe-arm device for use in a fuel-air explosive munition carried by an craft. The device has a housing having an environmental seal which is separated from the housing upon munition release to form a seal opening, a pressure probe for obtaining static and dynamic air pressure and extending through the seal opening when deployed, a piston and rod which is driven upon sensing of a sufficient differential air pressure between the static and dynamic air pressure probe, a safety lock which locks a pyrotechnic rotor and which disengages upon full extension of the piston rod, and an arming spring which is compressed by extension of the piston rod and which drives the pyrotechnic rotor for rotation against a mechanical escapement device thus providing for a timed rotation. The pyrotechnic rotor has two explosive wheels, each having switched detonators and upon receipt of electronic signals two explosive trains with a controlled time delay therebetween are initiated.

Abstract: An extremely fast operating, explosive operated, switch wherein a torus supports and insulates the facing ends of flat wires of the open circuit to be closed. An explosive input is applied to a conducting piston swage member which normally is insulated from the flat wires by the torus. This moves the swage portion of the member into the torus which forces it off of the ends of the wire. The swage portion then closes the circuit by jamming the frustro-conical swage surface thereof into both flat wires.

Abstract: An improved switch actuator, for safe and arm applications requiring utmost ependability in order to preclude a premature or false arming sequence, utilizes a plurality of simultaneous input signals from independently coded pneumatic, optical and electrical sources to drive a rotary switch. A rotary fluidic valving plate is used to decode non-uniform input optical signals into a uniform cyclical output pressure signal which is used to drive a fail-safe, reversible pneumatic gerotor type motor. A geneva mechanism is used to mechanically couple the prime mover to an output gear to activate a switch. Alternatively, an electrical switch may be incorporated within the housing of the actuator.

Abstract: A differential drag apparatus is disclosed for detecting air pressure forces on a drag-sensing body. The body is movable in response to a predetermined magnitude of air pressure force. A pressure regulator responds to the movement of the body by releasing uniform pressure to an activation system. The activation system in turn releases a trigger provided the air pressure force acting against the drag-sensing body remains above the predetermined magnitude for a predetermined length of time. The trigger upon release may perform any number of activates such as opening or closing an electrical circuit, initiating a mechanical response, i.e. releasing a parachute, or detonating a small munition charge. The detonation of a charge, for example, may in turn ignite a rocket motor, release an explosive, or any other of related activities. The apparatus is insensitive to short duration forces above or below the predetermined magnitude, and radiation as results from proximate nuclear blast.

Abstract: A signaling device to be launched underwater having a fuze body and a protile containing pyrotechnic compositions. The pyrotechnic compositions are ignited by an electrical squib which is detonated by voltage from a sea water battery which is sealed from sea water until a valve opens to permit entry of water into the fuze. An open circuit is provided between the battery and leads of the squib and, in addition, the squib leads are shorted. The opening of a valve to permit entry of sea water into the fuze causes the short to be removed and closes the circuit between the battery and the squib.

Abstract: A switch actuator, for safe and arm applications requiring utmost dependaity in order to preclude a premature or false arming sequence, utilizes a plurality of simultaneous input signals from independently coded pneumatic optical and electrical sources to drive a rotary switch. A rotary fluidic valving plate is used to decode non-uniform input optical signals into a uniform cyclical output pressure signal which is used to drive a fail-safe, reversible pneumatic piston type motor. A geneva mechanism is used to mechanically couple the prime mover to an output gear.