Compact inertial igniters for munitions and the like with high-g shock protection

Abstract

An inertial igniter including: a base; a first movable member, movable relative to the base in a first direction, the first movable member having a blocking portion; a second movable member movable relative to the base in a second direction, the second movable member having an engaging portion and an activation portion; and an intermediary member having a first portion engaged with the engaging portion and a second portion engaged with the blocking portion. Wherein upon the base experiencing an acceleration profile greater than a predetermined acceleration profile, the blocking portion disengages with the second portion allowing the intermediary member to move such that the first portion disengages with the engaging portion allowing the activation portion to move from an inactivated position to an activated position.

What is claimed is: 
     
         1 . An inertial igniter comprising:
 a base;   a first movable member, movable relative to the base in a first direction, the first movable member having a blocking portion;   a second movable member movable relative to the base in a second direction, the second movable member having an engaging portion and an activation portion; and   an intermediary member having a first portion engaged with the engaging portion and a second portion engaged with the blocking portion;   wherein upon the base experiencing an acceleration profile greater than a predetermined acceleration profile, the blocking portion disengages with the second portion allowing the intermediary member to move such that the first portion disengages with the engaging portion allowing the activation portion to move from an inactivated position to an activated position.   
     
     
         2 . The inertial igniter of  claim 1 , wherein the second direction is one of offset from the first direction or parallel with the first direction. 
     
     
         3 . The inertial igniter of  claim 1 , wherein the first direction and the second direction are in rotation, wherein the rotation of the first direction is opposite to a rotation of the second direction. 
     
     
         4 . The inertial igniter of  claim 1 , further comprising a first basing material for biasing the first movable member towards a position engaging the blocking portion with the second portion. 
     
     
         5 . The inertial igniter of  claim 4 , wherein the first basing material is a compression spring. 
     
     
         6 . The inertial igniter of  claim 4 , wherein the first movable member further comprises a stop for limiting a movement of the first movable member relative to the base in a biasing direction of the first biasing material. 
     
     
         7 . The inertial igniter of  claim 1 , further comprising a second biasing material for biasing the second movable member towards the activated position. 
     
     
         8 . The inertial igniter of  claim 7 , wherein the second basing material is one of a compression spring or torsion spring. 
     
     
         9 . The inertial igniter of  claim 1 , further comprising a third basing material for biasing the intermediary member towards a position disengaging the first portion from the engaging portion. 
     
     
         10 . The inertial igniter of  claim 9 , wherein the third basing material is a compression spring. 
     
     
         11 . The inertial igniter of  claim 1 , wherein the first movable member is configured to move in the first direction linearly relative to the base. 
     
     
         12 . The inertial igniter of  claim 11 , wherein the second movable member is configured to move in the second direction linearly relative to the base. 
     
     
         13 . The inertial igniter of  claim 12 , wherein the intermediary member is configured to rotate relative to the base about a pivot positioned between the first portion and the second portion. 
     
     
         14 . The inertial igniter of  claim 1 , wherein the first movable member is configured to move in the first direction in rotation relative to the base. 
     
     
         15 . The inertial igniter of  claim 14 , wherein the second movable member is configured to move in the second direction in rotation relative to the base. 
     
     
         16 . The inertial igniter of  claim 15 , wherein the intermediary member is configured to move in rotation relative to the base. 
     
     
         17 . The inertial igniter of  claim 1 , wherein the first direction is one of parallel to a direction of acceleration of the base or parallel to a direction opposite to the acceleration of the base. 
     
     
         18 . The inertial igniter of  claim 1 , wherein at least a portion of the movement of the blocking portion in the first direction is one parallel to a direction of acceleration of the base or parallel to a direction opposite to the acceleration of the base. 
     
     
         19 . The inertial igniter of  claim 1 , further comprising an activation prevention mechanism movable between an activation allowing position which does not interfere with the blocking portion of the first movable member from disengaging with the second portion of the intermediary member and an activation preventing position preventing the blocking portion of the first movable member from disengaging with the second portion of the intermediary member when a magnitude of the acceleration profile is greater than a magnitude of the predetermined acceleration profile. 
     
     
         20 . The inertial igniter of  claim 19 , wherein the activation prevention mechanism comprises a blocking member movable into a path of movement of the first movable member upon the magnitude of the acceleration profile is greater than the magnitude of the predetermined acceleration profile. 
     
     
         21 . The inertial igniter of  claim 20 , wherein the blocking member moves between the activation allowing position and the activation preventing position in one of translation or rotation. 
     
     
         22 . The inertial igniter of  claim 20 , wherein the movable member is configured to be biased in the activation allowing position returning the movable member to the activation allowing position after moving to the activation preventing position. 
     
     
         23 . The inertial igniter of  claim 20 , wherein the movable member is configured to be prevented from returning to the activation allowing position after moving to the activation preventing position. 
     
     
         24 . The inertial igniter of  claim 1 , further comprising a removable safety pin blocking one of the intermediary member or the first member from moving. 
     
     
         25 . The inertial igniter of  claim 1 , wherein the first member, second member and intermediary member are each independently rotatable on a common shaft. 
     
     
         26 . The inertial igniter of  claim 1 , wherein the activation portion comprises a tip and the inertial igniter further comprises a percussion primer, where the tip is configured to activate the percussion primer when the tip moves to the activated position. 
     
     
         27 . The inertial igniter of  claim 1 , wherein the activation portion comprises a tip and the inertial igniter further comprises a circuit, where the tip is configured to one of open or close the circuit when the tip moves to the activated position.