Closure for a pyrotechnic unit

Abstract

A closure for a pyrotechnic unit ensures that upon the build-up of pressure of a pyrotechnic charge ( 24 ) no pieces which fly off occur. That is achieved in that the cover ( 4 ) has a desired-rupture location ( 32 ) in the form of a circular ring, except for a portion ( 14 ), wherein the residual cover ( 36 ) which tears open is non-detachably connected to the cover ( 4 ).

1 . A closure for a pyrotechnic unit in which a case ( 22 ) is closed with a cover ( 4 ) with a collar ( 6 ), wherein after firing of a pyrotechnic charge ( 24 ) in the case ( 22 ) the internal pressure causes opening at the cover part, characterised in that 
 the cover ( 4 ) has a desired-rupture location ( 32 ) in the form of a circular ring, except for a portion ( 14 ),    wherein the residual cover ( 36 ) which tears open is non-detachably connected to the cover ( 4 ).    
     
     
         2 . A closure according to  claim 1  characterised in that the desired-rupture location ( 32 ) is near the collar ( 6 ).  
     
     
         3 . A closure according to  claim 1  characterised in that the portion ( 14 ) is 5-60°.  
     
     
         4 . A closure according to  claim 1  characterised in that the cover ( 4 ) is glued to the case ( 22 ) in the region of its collar ( 6 ).  
     
     
         5 . A closure according to  claim 4  characterised in that the collar ( 6 ) bears externally against the case ( 22 ).  
     
     
         6 . A closure according to  claim 1  characterised in that the cover ( 4 ) comprises aluminium and has a stamping ( 12 ) at its inside ( 10 ).  
     
     
         7 . A closure according to  claim 6  characterised in that the cover ( 4 ) is of a thickness of from 0.6 to 1.8 millimeter and the residual thickness ( 26 ) in the region of the stamping is from 0.1 to 0.3 millimeter.