Thermal safety valve for automatically shutting off pipes

A thermally triggered safety device to automatically shut off the fluid in pipelines, especially gas pipelines, in case of impermissible temperature rises, a casing (1) of which has an integrated seat (7) and a metal closing body (5), that is located in axial extension to said seat (7) and which has a sealing area (14) facing said seat (7), followed by a necking (15) on said closing body's side opposite to said seat, and a collar (17) that forms a control edge, by which said closing body (5) is kept in an open position under the force exercised in a closing direction by a closing spring (9), which spring is under tension and is sitting to a great extent inside a pocket hole (16), provided in said body by means of a tappet (20) whose one end rests on a fusible soft solder component (21), and the other end engages the closing body's (5) surface near the collar (17), CHARACTERIZED IN THAT inside said casing (1), three or more ribs (8) are arranged with their longitudinal axes parallel to said closing body's (5) direction of movement when closing so that each of said ribs (8) forms a slide-way for said closing body (5) moving from an open into a closed position, and there is cut into each of said ribs (8) a first groove (10) in which is placed a shaped part (11) that supports said closing spring (9), and at least said ribs (8) arranged approximately opposite to said tappet (20) have a second groove whose side facing said seat (7) forms a rest edge (18) on which said collar's (17) control edge may rest when said closing body (5) is in open position, whereas in case of melting away said fusible soft solder component (21), and the change of said tappet's (20) position as a consequence of said melting off, said control edge does no longer rest on said rest edge (18), and said closing body (5), driven by said closing spring (9) switches over into its closed position.