Electrical Discharge Immobilization Weapon Projectile Having Multiple Deployed Contacts

Abstract

A unitary projectile for an immobilization weapon and tethered by two electrical wires, has a plurality of electrical contacts including several contacts dispersed in a spaced pattern around the projectile after target impact. The pattern of several contacts substantially increases the probability that if the projectile hits the target, an immobilization circuit through the target will be completed. The deployment of the contacts occurs as a result of the sudden deceleration of the projectile when it impacts the target. This simplifies the deployment as well as the projectile configuration and likely reduces the risk of misactivation or an ill-timed activation of the second contacts. In a preferred version of the disclosed embodiments, there are preferably four contacts dispersed in a symmetrical arrangement around the projectile. The immobilization voltage in preferably applied to one pair of opposed contacts and then to the other in an oscillating fashion in order to increase the likelihood of disabling effect.

I claim: 
     
         1 . A dual wire-tethered unitary projectile for use in an electrical discharge immobilization weapon wherein the projectile is fired using a propulsive force toward a remote target for imparting an electrical current through the target after impact; the projectile comprising:
 a dual wire-tethered projectile body;   a plurality of contact arms rotatably secured to the projectile body and having a first stable position during projectile flight toward the target and a second stable position after impact of the projectile with the target;   said first stable position being aerodynamic to promote an accurate trajectory of said body;   said second stable position forming a pattern of spaced contact arm locations for increasing the probability of electrical contact with said target;   wherein transition from said first stable position to said second stable position is implemented by a plunger in said projectile body and which translates in response to projectile impact with a target.   
     
     
         2 . The projectile recited in  claim 1  further comprising a retainer for maintaining said contact arms in said first stable position during said projectile flight and wherein said contact arms are configured for movement from said first stable position to said second stable position by said projectile body upon its impact with a target causing movement of said plunger and release of said retainer. 
     
     
         3 . The projectile recited in  claim 1  wherein each of said contact arms terminates in a barb for promoting adherence of each contact arm to the target in said second stable position. 
     
     
         4 . The projectile recited in  claim 1  wherein said projectile body comprises a plurality of elongated grooves for receiving said contact arms in their first stable position. 
     
     
         5 . The projectile recited in  claim 1  wherein said projectile body comprises a contact barb affixed to said plunger and extending toward the target. 
     
     
         6 . The projectile recited in  claim 1  said body having an outer profile defined by the dimensions of said body and wherein when said contact arms are in said first stable position, no portion of said arms lies outside said body profile. 
     
     
         7 . The projectile recited in  claim 1  further comprising an electronic circuit contained within said body and being connected to each of said contact arms for activating selected ones of said contact arms to provide an effective immobilization current through said target. 
     
     
         8 . The projectile recited in  claim 7  wherein said electronic circuit also comprises at least one switch for selecting at least one contact arm to transmit said immobilization current through said target. 
     
     
         9 . The projectile recited in  claim 1  wherein said plurality of contact arms comprises at least two such contact arms. 
     
     
         10 . The projectile recited in  claim 1  wherein said projectile is contained in a cartridge prior to firing and wherein said propulsive force is generated by an air bag initiator within said cartridge. 
     
     
         11 . A dual wire-tethered unitary projectile for use in an electrical discharge immobilization weapon wherein the projectile is fired using a propulsive force toward a remote target for imparting an electrical current through the target after impact; the projectile comprising:
 a dual wire-tethered projectile body;   at least two symmetrically spaced contact members secured to the projectile body and having a first stable position during projectile flight toward the target and a second stable position after impact of the projectile with the target;   said first stable position being aerodynamic to promote an accurate trajectory of said body;   said second stable position forming a pattern of spaced contact member locations for increasing the probability of electrical contact with said target;   wherein transition from said first stable position to said second stable position is implemented by a plunger contained within said projectile body and which translates in response to projectile impact with a target.   
     
     
         12 . The projectile recited in  claim 11  wherein said projectile body comprises a central attachment member affixed to the body and extending toward the target for translating said plunger upon impact. 
     
     
         13 . The projectile recited in  claim 11  further comprising a retainer for maintaining said contact arms in said first stable position during said projectile flight and wherein said contact members are configured for movement from said first stable position to said second stable position by a sudden deceleration of said projectile body upon its impact with a target causing movement of said plunger and release of said retainer. 
     
     
         14 . The projectile recited in  claim 11  wherein each of said contact members terminates in a barb for promoting adherence of each contact member to the target in said second stable position. 
     
     
         15 . The projectile recited in  claim 11  further comprising an electronic circuit contained within said body and being connected to each of said contact members for activating selected ones of said contact members to provide an effective immobilization current through said target 
     
     
         16 . The projectile recited in  claim 15  wherein said electronic circuit also comprises at least one switch for selecting at least one contact member to transmit said immobilization current through said target. 
     
     
         17 . The projectile recited in  claim 11  wherein said projectile is contained in a cartridge prior to firing and wherein said propulsive force is generated by a sudden increase in pressure within said cartridge caused by an air bag initiator. 
     
     
         18 . A wire-tethered projectile for use in an electrical discharge weapon for disabling a remote target upon propulsion of the projectile toward the target by generation of a sudden increase in pressure within a cartridge initially containing said projectile, said projectile-containing cartridge comprising an air bag initiator for causing said sudden increase in pressure in response to application of an electrical current. 
     
     
         19 . The projectile recited in  claim 18  wherein a plurality of contact arms are configured to be deployed upon contact of said projectile with said remote target. 
     
     
         20 . The projectile recited in  claim 19  wherein said projectile comprises a plunger which translates upon said projectile impact with said target for causing said deployment of said contact arms. 
     
     
         21 . The wire-tethered projectile recited in  claim 18  wherein said projectile is one of a pair of projectiles each positioned in a respective dart holder within said cartridge.