Abstract: A catalytic exhaust unit for an automobile vehicle intended for the chemical treatment of a gaseous mixture in contact with a catalytic material. The exhaust unit includes a body with an entry and an exit for the flow of a gaseous mixture. The interior of the body includes two successive compartments. A filtering material is arranged in the first compartment, and a treatment receptacle is arranged in the second compartment. A mass of catalytic material, permeable to the passage of the gaseous mixture is arranged in the receptacle. The catalytic material is in solid form and includes an active substance consisting of metals and obtained by partial sintering. The mass of the catalytic material is arranged in a succession of at least two catalyst beds in the direction of flow of the gaseous mixture. The first bed includes copper as an active substance, and each of the other beds includes, by way of an active substance, at least one metal chosen from among copper, iron, nickel, cobalt, cadmium, and chromium.

Abstract: A safety device for controlling circulation of a cooling fluid of an engine includes a valve seat, a poppet movable toward and away from the valve seat, and a temperature sensing device including a movable element for controlling the movement of the poppet toward and away from the valve seat. A eutectic solder element connects the poppet to the movable element and melts at a predetermined safety temperature. A first spring engages and urges the movable element and hence the poppet toward an engagement with the valve seat. A second spring engages and urges the poppet away from the valve seat opposite to the first spring. Thus, if the cooling fluid reaches the safety temperature and the solder element melts, the second spring moves the poppet away from the valve seat and allows the cooling fluid through the valve seat.