Electric initiator and initiator assembly using it

Abstract

The present invention provides an electric type initiator having a stable electric characteristic, and thereby provides an electric type initiator having better reliability and an initiator assembly using the same. The present invention provides an electric type initiator comprising two electroconductive bodies, an insulating body provided between top portions of the electroconductive bodies, and an electric resistance wire spanned between the top portions of the electroconductive bodies which are exposed from an upper end portion of the insulating body, wherein a distance (L) of the electric insulating body between the top portions of the two electroconductive bodies is set to be not less than 0.8 times a horizontal distance (1) of a portion which determines the resistance value of the electric resistance wire between the electroconductive bodies.

1 . An electric type initiator comprising two electroconductive bodies, an insulating body provided between top portions of the electroconductive bodies, and an electric resistance wire spanned between the top portions of the electroconductive bodies which are exposed from an upper end portion of the insulating body, and the top portions of the two electroconductive bodies arranged to be flush with an upper end surface of the electric insulating body, 
 wherein a distance (L) of the electric insulating body between the top portions of the two electroconductive bodies is set to be not less than 0.8 times a horizontal distance (1) of a portion which determines the resistance value of the electric resistance wire between the electroconductive bodies.    
     
     
         2 . An electric type initiator according to  claim 1 , wherein a distance (L) of the electric insulating body between the top portions of the two electroconductive bodies is set to be not less than 0.83 times the horizontal distance (1) of a portion which determines the resistance value of the electric resistance wire between the electroconductive bodies.  
     
     
         3 . An electric type initiator according to  claim 1 , wherein the distance (L) of the electric insulating body between the top portions of the two electroconductive bodies is set to be not less than 0.9 times the horizontal distance (1) of a portion which determines the resistance value of the electric resistance wire between the electroconductive bodies.  
     
     
         4 . An electric type initiator according to any one of  claims 1  to  3 , comprising a priming which is ignited and burnt by heat generation of the electric resistance wire, 
 wherein a current applied between the two electroconductive bodies, which is required for igniting the priming, is set to be not more than 1.75 A for application time of 2 milliseconds.  
 
     
     
         5 . An electric type initiator according to any one of  claims 1  to  3 , comprising the priming which is ignited and burnt by heat generation of the electric resistance wire, 
 wherein a current applied between the two electroconductive bodies, which is required for igniting the priming, is set to be not more than 1.2 A for application time of 2 milliseconds.  
 
     
     
         6 . An electric type initiator according to any one of  claims 1  to  5 , wherein the resistance value between the electroconductive bodies after a voltage of 25 kv is applied between two electroconductive pins more than five times in an electric circuit for conducting a test provided in MIL-STD-1512 METHOD 205 of MIL standard in which a charging capacity is 150 PF and a discharging resistance is 500 Ω is within 10% of the resistance value between the electroconductive bodies before application of the voltage.  
     
     
         7 . An electric type initiator according to any one of  claims 1  to  5 , wherein the resistance value between the electroconductive bodies after a voltage of 25 kv is applied between two electroconductive pins more than five times in an electric circuit for conducting a test provided in MIL-STD-1512 METHOD 205 of MIL standard in which a charging capacity is 150 PF and a discharging resistance is 500 Ω is within 8% of the resistance value between the electroconductive bodies before application of the voltage.  
     
     
         8 . An electric type initiator comprising two electroconductive bodies, an insulating body provided between top portions of the electroconductive bodies, and an electric resistance wire spanned between the top portions of the electroconductive bodies which are exposed from an upper end portion of the insulating body, and the top portions of the electroconductive bodies arranged to be flush with an upper end surface of the electric insulating body, 
 wherein the resistance value between the electroconductive bodies after a voltage of 25 kv is applied between two electroconductive pins more than five times in an electric circuit for conducting a test provided in MIL-STD-1512 METHOD 205 of MIL standard in which a charging capacity is 150 PF and a discharging resistance is 500 Ω is within 10% of the resistance value between the electroconductive bodies before application of the voltage.    
     
     
         9 . An electric type initiator according to  claim 8 , wherein the resistance value between the electroconductive bodies after a voltage of 25 kv is applied between two electroconductive pins more than five times in an electric circuit for conducting a test provided in MIL-STD-1512 METHOD 205 of MIL standard in which a charging capacity is 150 PF and a discharging resistance is 500 Ω is within 8% of the resistance value between the electroconductive bodies before application of the voltage.  
     
     
         10 . An electric type initiator according to any one of  claims 1  to  9 , wherein the electric type initiator comprises a first electroconductive pin, a metallic eyelet having a hole through which the electroconductive pin passes and electrically connected with a second electroconductive pin, and an insulating body filled in the hole to insulate the first electroconductive pin from the eyelet, 
 wherein the two electroconductive bodies are the first electroconductive pin and the metallic eyelet electrically connected to the second electroconductive pin.  
 
     
     
         11 . An electric type initiator according to any one of  claims 1  to  10 , wherein the electric type initiator comprises two electroconductive bodies comprising the first electroconductive pin and the second electroconductive pin, and an insulating body in which the electroconductive body passes through.  
     
     
         12 . An initiator assembly comprising the electric type initiator according to any one of  claims 1  to  11  and a metal collar member which partially surrounds an outer periphery of the insulating body of the electric type initiator.  
     
     
         13 . A gas generator for an air bag comprising, in a housing having a gas discharging port, an initiator assembly including an electric type initiator, a gas generating means activated upon an activation of the initiator assembly to generate an activating gas for inflating an air bag, wherein the initiator assembly is the initiator assembly according to  claim 12.