Pyrotechnic actuator equipped with a charge comprising an oxidant and a reducing agent which are separate

Abstract

The technical field of the invention is that of pyrotechnic actuators having the essential function either of inflating a structure or of displacing a component by way of a ram. The subject of the invention relates more specifically to a gas-generating actuator ( 1, 100 ) comprising an ignition system ( 3, 103 ) and an energetic charge. The main characteristic of the actuator ( 1, 100 ) is that the charge is made up of a reducing material ( 4, 104 ) and of an oxidizing fluid ( 2, 102 ) which are separate.

1 . Gas-generating actuator comprising an ignition system and an energetic charge, characterized in that the said charge is made up of a reducing material and of an oxidizing fluid which are separate.  
   
   
       2 . Actuator according to  claim 1 , characterized in that the reducing material is chosen from polymethyl methacrylate, cariflex, artificial and natural resins, metals and waxes.  
   
   
       3 . Actuator according to  claim 1 , characterized in that the oxidizing fluid is liquid.  
   
   
       4 . Actuator according to  claim 3 , characterized in that the oxidizing fluid is chosen from oxygen peroxide and hydroxylamine nitrate.  
   
   
       5 . Actuator according to  claim 1 , characterized in that the oxidizing fluid is gaseous.  
   
   
       6 . Actuator according to  claim 5 , characterized in that the oxidizing fluid is a gaseous mixture consisting mainly of oxygen.  
   
   
       7 . Actuator according to  claim 1 , characterized in that the reducing material consists of a solid cylindrical block through which at least one duct passes longitudinally.  
   
   
       7 . Actuator according to  claim 7 , characterized in that the block has, passing longitudinally through it, a central duct exhibiting at least three mutually parallel longitudinal grooves uniformly distributed around the said duct.  
   
   
       8 . Actuator according to  claim 7 , characterized in that the block has, passing longitudinally through it, seven mutually parallel ducts of which one is in a central position and the other six are uniformly distributed around the said central duct and are equidistant therefrom.  
   
   
       9 . Actuator according to  claim 5 , characterized in that the flowrate of oxidant is controlled by a pyrotechnic valve and a regulating valve which are situated between the reserve of oxidant and the reducing material.  
   
   
       10 . Actuator according to  claim 1 , characterized in that the ignition system comprises at least one pyrotechnic initiator and a pyrotechnic booster charge, the said system being positioned in such a way that the gases emitted by the said booster charge heat the surface of the reducing material.  
   
   
       11 . Actuator according to  claim 11 , characterized in that the oxidant is brought into contact with the reducing material after the surface of the said material has been heated, so as to bring about a pyrolysis reaction, and the gases thus emitted are conveyed out of the said actuator by means of an outlet pipe.  
   
   
       12 . Actuator according to  claim 12 , characterized in that the gases produced by the pyrolysis reaction between the reducing material and the oxidant are cooled by means of a parallel circuit comprising a cooling liquid.  
   
   
       13 . Actuator according to  claim 13 , characterized in that the circuit comprises, in succession, an expansion chamber comprising the gas outlet pipe, a reserve of cooling liquid and a connecting pipe connecting the said reserve and the said outlet pipe, the said connecting pipe being fitted with a pyrotechnic valve.  
   
   
       14 . Actuator according to  claim 14 , characterized in that the expansion chamber, which has a moving wall in contact with the cooling liquid, is capable of expanding under the effect of the gases produced by the pyrolysis, thereby exerting pressure on the cooling liquid.  
   
   
       15 . Actuator according to  claim 5 , characterized in that the flowrate of oxidant is controlled by a funnelled nozzle situated between the reserve of oxidant and the reducing material.  
   
   
       16 . Actuator according to  claim 16 , characterized in that the gases emitted by the pyrolysis reaction between the oxidant ( 102 ) and the reducing material are routed towards a buffer volume opening onto a ram equipped with a piston.