Initiator and gas generator

Abstract

An initiator includes a casing, a reactant disposed in the casing, and electrodes arranged to contact the reactant. The reactant contains an electrically conductive substance in a manner such that once a voltage is applied to the electrodes, an electric current flows through the electrically conductive substance, thereby initiating a reaction of the reactant. The initiator is easily manufactured with low manufacturing cost.

What is claimed is:  
     
         1 . An initiator, comprising: 
 a casing,    a reactant disposed in the casing and containing an electrically conductive substance, and    electrodes situated inside the casing to contact the reactant such that when a voltage is applied to the electrodes, an electric current flows through the electrically conductive substances, thereby initiating a reaction of the reactant.    
     
     
         2 . An initiator according to  claim 1 , wherein said electrically conductive substance includes at least ones of metal particles and metal oxide particles.  
     
     
         3 . An initiator according to  claim 1 , wherein said reactant contains metal oxide particles having oxidization activity and metal particles having electrical conductivity.  
     
     
         4 . An initiator according to  claim 1 , wherein said electrodes are pin members having front-end portions extending into the reactant.  
     
     
         5 . An initiator according to  claim 1 , further comprising a metal member electrically connected to one of the electrodes and contacting the reactant.  
     
     
         6 . An initiator according to  claim 5 , further comprising an oxidized film covering the metal member.  
     
     
         7 . An initiator according to  claim 5 , wherein said metal member has a porous surface to improve reaction response.  
     
     
         8 . An initiator according to  claim 5 , further comprising a pre-assembled block formed of the reactant connected to the other of the electrodes.  
     
     
         9 . An initiator according to  claim 8 , wherein said pre-assembled block further includes a surrounding material covering the reactant, said metal member contacting the surrounding material.  
     
     
         10 . A gas generator comprising the initiator according to  claim 1 , and a gas generating agent to be ignited by the initiator for generating a gas.