Safety Valve for a Compressed Gas Container

Abstract

A safety valve for a compressed gas container having an overflow duct ( 2 ) connected to the compressed gas container and having an outlet duct ( 3 ) and having a thermal triggering unit which comprises a closure body ( 15; 20 ) that is displaceable out of a standby position in which it holds the overflow duct tightly sealed with respect to the outlet duct in cooperation with a sealing element ( 9 ), into a release position in which the overflow duct ( 2 ) is connected to the outlet duct and also comprises a burst body ( 8 ) which is arranged between an abutment and a closure body ( 15; 20 ) to hold the latter in the standby position, such that the thermal triggering unit comprises a spring element ( 10; 11; 21 ) which exerts a spring force directed in the direction of the abutment on the burst body ( 8 ), characterized in that the closure body ( 15; 20 ) is an element having an essentially wedge-shaped cross section and having rotational symmetry about a central axis, said element engaging in the inside diameter of the O ring and pressing it at least radially against a wall of the overflow duct ( 2 ) with its sealing surface ( 28 ) which is designed in a wedge shape, being broader at its wider diameter than the inside diameter of the O ring as the sealing element ( 9 ).

1 . A safety valve for a compressed gas container having an overflow duct connected to the compressed gas container and an outlet duct and having a thermal triggering unit, which comprises a closure body that is displaceable out of a standby position in which it holds the overflow duct tightly sealed with respect to the outlet duct in cooperation with a sealing element, into a release position in which the overflow duct is connected to the outlet duct and also comprises a burst body, which is arranged between an abutment and a closure body to hold the latter in the standby position, such that the thermal triggering unit comprises a spring element which exerts a spring force directed in the direction of the abutment on the burst body, wherein the closure body is an element having an essentially wedge-shaped cross section and having rotational symmetry about a central axis, said element engaging in the inside diameter of the O ring and pressing it at least radially against a wall of the overflow duct with its sealing surface which is designed in a wedge shape, being broader at its wider diameter than the inside diameter of the O ring as the sealing element. 
   
   
       2 . The safety valve according to  claim 1  wherein the sealing surface has a concave curvature. 
   
   
       3 . The safety valve according to  claim 2  wherein the curvature of the sealing surface having a concave curvature corresponds in its curvature to the curvature of a sealing surface of the O ring in at least one section. 
   
   
       4 . The safety valve according to  claim 1  wherein a first shoulder is provided in the overflow duct, a first plate spring resting on said shoulder, the O ring resting on said first plate spring and supported thereon and on the wall of the overflow duct in a sealing manner, such that the closure body is in contact with the O ring on the side opposite the first plate spring and a second plate spring is arranged on the side of the closure body opposite the O ring, resting on a second shoulder formed in the overflow duct and the burst element being supported on the side thereof opposite the closure body. 
   
   
       5 . The safety valve according to  claim 1  wherein the spring element is arranged on the side of the burst body opposite the abutment. 
   
   
       6 . The safety valve according to  claim 1  wherein the spring element is a plate spring placed on a shoulder in the overflow duct. 
   
   
       7 . The safety valve according to  claim 1  wherein the burst body is a fluid-filled glass ampoule clamped axially between the closure body and the abutment.