Abstract: A thermostatic safety valve includes a cage (1) inserted in an engine cooling circuit and defining an upstream chamber (16) having a flow opening (5) and a downstream chamber (17) having a flow opening (6) with communication between the chambers being controlled by a moving valve member (15, 26) cooperating with a fixed seat (23) and carried by a thermostatic capsule (9) which is subjected to the opposing actions of a thermally expandable material (14) that it contains acting on a thrust element (8) and spring (18). The valve member comprises two elements, a central element (15) integral with the capsule (9) and urged by a spring (18) towards the seat (23), and a peripheral seal (26) having a deformable lip seal (29) engageable with the valve seat in the closed position of the valve and disengageable from the valve seat for movement into the downstream chamber by the force of the spring in the event of leaking of the thermally expendable material from the capsule and/or breaking of the thrust element.

Abstract: A thermostatic safety valve includes a cage (1) inserted in an engine cooling circuit and defining an upstream chamber (16) having a flow opening (5) and a downstream chamber (17) having a flow opening (6) with communication between the chambers being controlled by a compound moving valve member (15, 21) cooperating with a fixed seat (23) and carried by a thermostatic capsule (9) which is subjected to the opposing actions of a thermally expandable material (14) that it contains and springs (18, 22). The valve member comprises two elements, firstly a peripheral element (21) situated in the upstream chamber (16) and urged by a first spring (22) against the seat (23), and secondly a central element (15) integral with the capsule (9) and pressing against the downstream face of the peripheral valve element (21) by the action of the capsule and thermally expandable material (14) and moving away therefrom under the force of a second spring (18).