Self-cleaning low emission bleeder valve type liquid level gauge

A bleeder valve having an automatic orifice cleanout element, the bleeder valve being adapted to be mounted in a wall of a pressurized gas tank for bleeding pressurized gas therefrom, the valve comprising:

• a valve body that is sealably mounted in a wall opening in the wall of the tank, the valve body having a valve opening therein that provides fluid communication between an inner end of the valve body, which is in fluid communication with the interior of the tank, and an outer end, which is in fluid communication with the exterior of the tank, the valve opening including an enlarged internally threaded exterior portion and a reduced diameter interior portion, the reduced diameter interior portion of the opening comprising a flow restriction orifice that limits pressurized gas flow through the valve opening in the valve body from the interior to the exterior of the tank;
• and
• a valve member that fits in the valve opening in the valve body, the valve member including a threaded shank that threads into the enlarged portion of the valve opening, the valve member further including a narrow shaft extending in an axial direction from an inner end of the threaded shank, the shaft fitting into the flow restriction orifice as the valve member is threaded into the valve body, the shaft being shaped so that threading of the valve member into the valve body causes the shaft to remove or dislodge foreign material accumulated in the interior of the flow restriction orifice, leaving the flow restriction orifice clear of foreign matter, the shaft being formed so as to partially limit flow of pressurized gas between the shaft and an inner wall of the flow restriction orifice so that assembly of the bleeder valve with the shaft disposed in the flow restriction orifice causes the shaft to restrict gas release through the flow restriction orifice, the shaft having an axially extending external recess therein through which gas can flow when the shaft is in the orifice, the shaft being formed in the shape of a drill bit with the recess comprising an external groove and with the external groove having a sharpened edge for removing foreign material from the orifice, the shaft thus automatically cleaning out the orifice each time the valve member is threaded into the opening, and providing an increased restriction of the orifice with the valve member threaded in the opening.