Safety and arming mechanism

Claim 2

In a fuze for an explosive projectile having a base section, a body section, and a nose section, a safety and arming mechanism including a firing train having a booster charge and acceleration-sensitive means for initiating fuze arming when the projectile to which the fuze is affixed is fired from a gun, the improvement comprising: an impact assembly located in the nose portion of the fuze, said impact assembly comprising a cartridge containing a dust under pressure, means for releasing said dust from said cartridge after the projectile to which the fuze is affixed is airborne, the action of the dust passing over the projectile serving to deposit an electrostatic charge upon the projectile.

Claim 3

The invention in accordance with claim 1 wherein said dust releasing means comprises a puncture pin disposed along the axis of the fuze and pointed forwardly, a spring concentric with said puncture pin normally urging the cartridge forwardly and away from said puncture pin, and a plurality of hollow pins disposed radially in the periphery of the nose section of the fuze, the said puncture pin adapted to rupture the cartridge when the cartridge moves rearwardly under the force of setback to compress the spring and engage the puncture pin, the said spring serving to separate the cartridge from the puncture pin when the force of setback abates, the rupture in the cartridge caused by penetration of the cartridge pin and the apertures in the hollow pins providing the escape path from the fuze for the charging dust.

Claim 4

The invention in accordance with claim 2 and means adapted to prevent the cartridge from engaging the puncture pin to release the charging dust from the cartridge, the result being that the fuze will not be charged electrostatically and will not function on proximity approach to the target, permitting the fuze to function on impact with the target.

Claim 5

The invention in accordance with claim 3 wherein the means adapted to prevent proximity function comprises a windshield attachable to and removable from the fuze, the said windshield when attached to the fuze adapted to prevent the hollow pins from moving outwardly when so urged by the cartridge on setback of the projectile, the said hollow pins, when so restrained, acting to prevent the engagement of the cartridge with the puncture pin, the electrostatic charging dust being thus prevented from escaping from the cartridge and from the fuze.

Claim 6

An electrostatic dust dispensing means for a proximity fuze comprising a cartridge, a sleeve and a cap forming a housing for said cartridge, a charging dust under pressure in said cartridge, a plurality of hollow pins extending radially from said sleeve, a puncture pin rigidly attached to the lower end of said sleeve with the point thereof disposed forwardly, and a helical spring contained within said sleeve and adapted to maintain the separation of the said cartridge and the said puncture pin, the said cartridge being adapted to move rearwardly relative to the said sleeve when the said means is subjected to the force of setback, the setback driving the cartridge rearwardly against the force of the helical spring to cause a penetration of the cartridge by the puncture pin, the hollow pins at the same time being driven outwardly by the cartridge as the cartridge moves rearwardly, the puncture of the cartridge permitting the charging dust to escape from the cartridge, and through the hollow pins.

Claim 7

An electrostatic dust dispensing means for a proximity fuze comprising a cartridge, a sleeve and a cap forming a housing for said cartridge, a charging dust under pressure in said cartridge, a plurality of hollow pins extending radially from said sleeve, a puncture pin rigidly attached to the lower end of said sleeve with the point thereof disposed forwardly, and a helical spring contained within said sleeve and adapted to maintain the separation of the said cartridge and the said puncture pin, the said cartridge being adapted to move rearwardly relative to the said sleeve when the said means is subjected to the force of setback, the setback driving the cartridge rearwardly against the force of the helical spring to cause a penetration of the cartridge by the puncture pin, the hollow pins at the same time being driven outwardly by the cartridge as the cartridge moves rearwardly, the puncture of the cartridge permitting the charging dust to escape from the cartridge, and through the hollow pins.

Claim 8

The invention in accordance with claim 5 and a windshield disposed around said sleeve, the said windshield being attachable to and removable from the fuze and when so attached adapted to prevent the hollow pins from moving outwardly when so urged by the cartridge acting against the said pins under the force of setback, the said hollow pins, when so restrained, preventing the engagement of the caRtridge with the puncture pin in order to prevent the electrostatic charging dust from escaping from the cartridge.

Claim 9

A firing train comprising a firing train block; a pair of spring loaded rotors oppositely disposed within a cavity formed in said block, each rotor having an explosive element positioned therein; means releasably engaging the first rotor and the first rotor releasably engaging the second rotor when the fuze is in the unarmed condition; an intermediate charge and an electric detonator housed in said block and in communication with one another, the intermediate charge being in alignment with the explosive element of the first rotor when the first rotor is in the armed position and out of alignment with said explosive element when the said first rotor is in the unarmed position, the electric detonator being in alignment with the explosive element of the second rotor when the said second rotor is in the armed position and out of alignment with the said explosive element when the said second rotor is in the unarmed position; a booster charge aligned with the explosive element of said second rotor when the said rotor is in the armed position and out of alignment with the said explosive element when the said rotor is in the unarmed position; means adapted to release the first rotor and the second rotor sequentially to bring the explosive elements into line with the intermediate charge, the electric detonator, and the booster charge; and means adapted to initiate the explosive element of the first rotor to detonate the booster charge through the explosive element of the second rotor, the electric detonator, and the intermediate charge.

Claim 10

A firing train comprising a firing train block; a pair of spring loaded rotors oppositely disposed within a cavity formed in said block, each rotor having an explosive element positioned therein; means releasably engaging the first rotor and the first rotor releasably engaging the second rotor when the fuze is in the unarmed condition; an intermediate charge and an electric detonator housed in said block and in communication with one another, the intermediate charge being in alignment with the explosive element of the first rotor when the first rotor is in the armed position and out of alignment with said explosive element when the said first rotor is in the unarmed position, the electric detonator being in alignment with the explosive element of the second rotor when the said second rotor is in the armed position and out of alignment with the said explosive element when the said second rotor is in the unarmed position; a booster charge aligned with the explosive element of said second rotor when the said rotor is in the armed position and out of alignment with the said explosive element when the said rotor is in the unarmed position; means adapted to release the first rotor and the second rotor sequentially to bring the explosive elements into line with the intermediate charge, the electric detonator, and the booster charge; and means adapted to initiate the explosive element of the first rotor to detonate the booster charge through the explosive element of the second rotor, the electric detonator, and the intermediate charge.

Claim 11

In a safety and arming mechanism for a fuze having within a body member a percussion primer mounted in a rotor, a recess in the rotor, a firing pin with one end in the recess, a spring biasing the firing pin away from the recess, and means for aligning the percussion primer with the firing pin responsive to the removal of the firing pin from the recess, the improvement comprising: a release plate holding the firing pin in the recess; a release shaft mounted for rotation; means responsive to the angular position of the release shaft for removing the release plate whereby the firing pin is free to move away from the recess; a safety pin mounted for sliding movement through the body member and in line with the firing pin; means including the safety pin for locking the firing pin in said recess; the safety pin having an aperture mounted for alignment with the firing pin; means including the aperture for locking the safety pin in place responsive to a premature release of the firing pin by said release plate coupled with movement of said aperture of said safety pin in alignment with the firing pin; and further means including the release shaft for locking the safety pin in place responsive to the angular position of the release shaft.

Claim 12

In a safety and arming mechanism for a fuze having within a body member a percussion primer mounted in a rotor, a recess in the rotor, a firing pin with one end in the recess, a spring biasing the firing pin away from the recess, and means for aligning the percussion primer with the firing pin responsive to the removal of the firing pin from the recess, the improvement comprising: a release plate holding the firing pin in the recess; a release shaft mounted for rotation; means responsive to the angular position of the release shaft for removing the release plate whereby the firing pin is free to move away from the recess; a safety pin mounted for sliding movement through the body member and in line with the firing pin; means including the safety pin for locking the firing pin in said recess; the safety pin having an aperture mounted for alignment with the firing pin; means including the aperture for locking the safety pin in place responsive to a premature release of the firing pin by said release plate coupled with movement of said aperture of said safety pin in alignment with the firing pin; and further means including the release shaft for locking the safety pin in place responsive to the angular position of the release shaft.

Claim 13

In a safety and arming mechanism for a fuze having within a body member a booster charge; a lead charge mounted in a lead charge rotor adjacent the booster charge but out of line therewith; a percussion primer mounted in a percussion primer rotor adjacent the lead charge but out of line therewith; a recess in the percussion primer rotor; a firing pin with one end in the recess; a spring biasing the pin away from the recess; and means for aligning the percussion primer with the firing pin and lead charge and aligning the lead charge with the booster charge response to the removal of the firing pin from the recess; the improvement comprising: a release plate holding the firing pin in the recess; a safety pin extending through the body and in line with the firing pin; the safety pin having an aperture mounted for alignment with the firing pin so that should the release plate fail to hold the firing pin, the firing pin will enter the aperture so that the safety pin may not be removed; a release shaft mounted for rotation; setback leaf means responsive to acceleration for locking the release shaft Gainst rotation; means on the release shaft and safety pin responsive to the angular position of the release shaft for locking said safety pin in place; a safety interlock mounted for rotation; a pin extending radially from the firing pin and in line with the safety interlock; means on the release shaft responsive to the angular position of the release shaft for permitting the safety interlock to rotate out of alignment with the pin on the firing pin; time delay means for moving said release plate away from the firing pin; and means responsive to the angular position of the release shaft for locking the time delay means.

Claim 14

In a safety and arming mechanism for a fuze having within a body member a booster charge; a lead charge mounted in a lead charge rotor adjacent the booster charge but out of line therewith; a percussion primer mounted in a percussion primer rotor adjacent the lead charge but out of line therewith; a recess in the percussion primer rotor; a firing pin with one end in the recess; a spring biasing the pin away from the recess; and means for aligning the percussion primer with the firing pin and lead charge and aligning the lead charge with the booster charge response to the removal of the firing pin from the recess; the improvement comprising: a release plate holding the firing pin in the recess; a safety pin extending through the body and in line with the firing pin; the safety pin having an aperture mounted for alignment with the firing pin so that should the release plate fail to hold the firing pin, the firing pin will enter the aperture so that the safety pin may not be removed; a release shaft mounted for rotation; setback leaf means responsive to acceleration for locking the release shaft Gainst rotation; means on the release shaft and safety pin responsive to the angular position of the release shaft for locking said safety pin in place; a safety interlock mounted for rotation; a pin extending radially from the firing pin and in line with the safety interlock; means on the release shaft responsive to the angular position of the release shaft for permitting the safety interlock to rotate out of alignment with the pin on the firing pin; time delay means for moving said release plate away from the firing pin; and means responsive to the angular position of the release shaft for locking the time delay means.