Integrated safe and arm apparatus

Abstract

An integrated Safe-Arm Device is an electrically activated, dual environm sensing mechanism which aligns a ball valve from a vented safe mode to a connected gas mode by sensing minimum sustained missile launch acceleration and minimum missile arming altitude prior to removing and setting various locks on the piston valve arming mechanism. The safing features have no stored energy and require the energy extracted from the environments to operate.

What is claimed is: 
     
       1. An integrated safe and arm device (ISAD) for a missile which comprises: a housing for hermetically sealing said ISAD there within and for providing a controlled atmosphere therefor;   exoatmospheric pressure sensor means operatively disposed in said housing for monitoring the reentry of said missile for sustained exoatmospheric flight;   propulsion sensor means operatively connected to said exatmospheric means for monitoring the performance of said missile during the powered flight portion of said missile's trajectory;   generator means for generating gas;   pneumatic control valve means operatively disposed external to said housing for directing gas from said generator means to a safety valve vent when said control valve means is in a safe position and to a turbo alternator port when said valve means is in an armed position;   motor and gear blocks assembly means operatively coupled to said propulsion sensor means and said exoatmospheric means for providing the mechanical force needed to lock and unlock said pressure and propulsion sensor means, and to arm and safe said valve means; and   environmentally powered safety lock means for preventing motion of said propulsion sensor means, and said exoatmospheric means during ground transportation and storage.   
     
     
       2. An ISAD as recited in claim 1 wherein said exoatmospheric pressure sensor means includes: an atmospheric reference drive piston assembly operatively supported in said housing;   a solenoid biased port seal pneumatically connected to said reference drive piston assembly;   a vacuum reference drive piston assembly operatively supported in said housing;   a manual spring biased reset vent is operatively disposed in said housing for venting said vacuum drive piston assembly;   an atmospheric drive arm is operatively connected to said atmospheric drive piston;   a vacuum drive arm operatively connects to said vacuum drive piston, said atmospheric drive piston assembly and said vacuum drive piston assemblies are connected to each other by said atmospheric drive arm and said vacuum drive arm respectively;   a timer assembly is operatively positioned on said atmospheric drive arm;   a biased timer release lever pivotally contacts said timer assembly;   an exoatmospheric drive arm shaft is fixedly connected to said atmospheric drive arm;   a pair of exoatmospheric safe and arm output cams are operatively supported on said drive arm shaft;   a biased velocity discriminator member is operatively supported on said drive arm shaft;   a control valve shaft unlock pin operatively engages the first cam of said pair of safe and arm output cams;   a biased drive arm safety lock rotatably contacts one end of said vacuum drive arm;   a transportation lock member rotatably interfaces with said atmospheric drive arm;   an atmospheric reference spring operatively provides a bias for said atmospheric drive arm;   a commit lock member rotatably interfaces with said atmospheric drive arm;   a main valve gear is rotatably mounted on said control valve shaft unlock pin; and   a plurality of electrical monitor switches operatively mounted on said exoatmospheric pressure sensor means and said propulsion sensor means, said control valve means and said motor and gear block assembly means indicate the positional status of said valve means, said exoatmospheric sensor means, and said propulsion sensor means.   
     
     
       3. An ISAD as recited in claim 2 wherein said propulsion sensor means includes: a plurality of parallel spaced rails;   a g-weight which operatively slides on said rails and responds to a boost acceleration of 4 g or greater;   a plurality of bias springs operatively attached to said g-weight, said bias springs being locked in an extended position when said g-weight has received a 4 g or greater impulse for 10 continuous seconds;   drive spring assembly means operatively coupled to said g-weight for storing energy from the translation of said g-weight from an initial position to its full stroke position;   escapement means operatively coupled to said drive spring assembly means for controlling the safety locking of said valve means;   a first spring biased transportation lock rotatably disposed on said g-weight;   a first transportation lock gear for connecting said first transportation lock to said motor and gear block assembly means;   removable second commit lock means for preventing said g-weight from returning to an original position if missile acceleration is sustained for 10 seconds;   a rack fixedly attached to said g-weight; and   a biased pinion operatively disposed on said rack rotates in response to said g-weight movement and is coupled to said drive spring assembly means.   
     
     
       4. An ISAD as recited in claim 3 wherein said drive spring assembly means includes: a spring biased commit lever contacting said second commit lock on one end;   a drive spring commit lever cam slidably coupled to said spring biased commit lever on its other ends;   a drive spring coupled to the pinion shaft of said biased pinion;   a timer output cam coupled to said drive spring;   a biased velocity discriminator lever rotably interfacing with said timer output cam;   a biased time start lever is operatively in alignment with said g-weight and activated thereby upon complete stroke of said g-weight;   60second timer means coupled to said time start lever, for releasing and regulating the energy stored in said drive spring; and   a propulsion safe and arm device output cam operatively connects said timer output cam to said escapement means.   
     
     
       5. An ISAD as recited in claim 4 wherein said pneumatic control valve means includes: a three way, two position internal pressure sealed valve.   
     
     
       6. An ISAD as recited in claim 5 wherein said motor and gear block assembly means includes: a D.C. torque motor;   an output pinion gear coupled to said torque motor;   a clutch assembly operatively connected to said output pinion gear;   a differential mechanically coupled to said clutch assembly, said differential including a differential free wheeling output gear;   a transportation brake lever supported by said housing rotatably in alignment with said differential free wheeling output gear;   a differential carrier shaft coupled to said differential;   a valve gear train mechanically coupled to said differential carrier shaft;   a valve brake lever rotatably in alignment with said differential; and   a missing link lever mechanically permits said valve gear train to engage and rotate said ball valve from a safe mode to an armed mode.   
     
     
       7. An ISAD as recited in claim 6 wherein said generator means includes; a gas generator output member having a port pneumatically connected to said ball valve means; and   a gas generator interference pin biasedly held in contact with the second cam of said pair of safe and arm output cams.