Air-relief valves

An air-relief valve, comprising;

• a housing having a connection at its lower end for connecting same to a water pipeline, and a large orifice at its upper end for releasing or admitting air when filling or emptying the water line;
• a float within the housing adapted to rise and descent with an increase and decrease in the level of the water within the housing, said float having an axially extending bore;
• a first valve member having a head at its upper and disposed between the float and the large orifice, a depending stem disposed in said axial bore of the float, and a small orifice through said first valve member head to establish communication between the underside of said first valve member head and said large orifice of the housing;
• a second valve member movable by said float such that when the float rises it causes the second valve member to close the small orifice in the first valve member, the rising of the float also causing the first valve member to rise and to close said large orifice in the housing;
• and an abutment carried by said first valve member engageable by said float during the descent of the float to cause the float to apply its weight to the first valve member tending to move same away from the large orifice.