| 主权项 |
1. A tool for use in connection with servicing gas valves wherein the gas valve includes an overpressure shut-off assembly that includes:
a body having an inlet for gas, an outlet for gas, and a passage interconnecting the inlet and outlet, the body including a first chamber having a passage to the gas inlet; a diaphragm positioned in the first chamber in a first or normal operating position or in a second or overpressure position, a holder attached to the diaphragm and having a cylindrical internal opening; the first chamber having a second chamber having internal threads, an axis substantially perpendicular to the diaphragm and having an external cap with a slot in threaded engagement with the internal threads of the second chamber so as to close the second chamber during the normal operating condition; a first spring located in the second chamber and biasing the diaphragm and holder to the first or normal operating position; a valve stem positioned within the first spring in the second chamber, the stem comprising an elongated cylindrical body including a first enlarged portion at the proximal end adjacent the second chamber cap and a second enlarged portion received and held in the holder internal opening when the diaphragm is in the first or normal operating position; a ring having external threads and diametrically opposed slots for receiving a tool, the ring axially positioned so as to maintain a bias on the first spring to maintain the diaphragm in the first or normal position; the distal end of the stem passing through an opening in the first chamber into the gas outlet and having a cylindrical member attached at the distal end including a stopper that is positioned adjacent the passage interconnecting the gas inlet and outlet to allow the flow of gas from the inlet to the outlet in normal operating condition; a second spring positioned within the gas outlet around the distal end of the stem adjacent the stopper and biasing the stem and stopper toward closing the interconnecting gas passage, the stem and stopper being prevented from movement until overpressure gas biases the diaphragm to an over-pressure condition that releases the second enlarged portion of the stem permitting the stem to move toward the outlet and thereby release the second spring to permit the stopper to close the outlet passage; the tool comprising: a cylindrical body having a transversely extending bar attached at a first end of the body, the first end of said body having a projection for mating with the slot in the cap, the second end of said body having an axial cylindrical opening defining an annular area and two opposed projections on the annular area for mating with the slots in the ring; and said bar having an arcuate projection on at least one end, said arcuate projection including a reduced diameter second arcuate projection for positioning over the first spring and stem after removal of the cap after the diaphragm is tripped by an over-pressure condition and capturing the first enlarged portion of the stem permitting the tool to forcibly move the stem back to the normal operating position thereby resetting the valve over-pressure shut-off assembly in preparation for further service. |
