Fluid flow fuse

A water flow fuse for automatically shutting off an excessive rate of flow of water in a system, comprising:

• a valve body having a water inlet passage and a water outlet passage in fluid communication with a valve seat opening;
• a first pressure-measuring passageway formed in the valve body and connected between the water inlet passage and a first pressure-sensing chamber;
• a restrictor removably held in the first pressure-measuring passageway;
• a valve member connected to a diaphragm and moveable through a guide element between a normally open position and a closed position against the valve seat opening;
• the diaphragm sealingly connected between the valve body and the valve member, downstream of the valve seat, above the guide element so as to form a second annular pressure-sensing area subject to downstream pressure in the water outlet passage and a separate upper are forming the first pressure-sensing chamber;
• a second, separate pressure-measuring passageway formed in the body and connected between the fluid outlet passage and the second annular pressure-sensing area, between the guide element and the diaphragm;
• at least one spring cooperating with the valve member, and the valve member and the at least one spring being sized and dimensioned so that when the flow of water through the body reaches a predetermined amount, a pressure differential will be created to slowly and smoothly move the diaphragm and the valve member through a number of flow controlling positions to a closed position against the valve seat without causing water hammer;
• and
• the valve member including a closed top portion and a bottom portion, with the closed top portion formed at a first of two ends;
• and the bottom portion being specifically shaped and formed at a second of two ends, and cooperating with the guide element to form a restricted passageway between the water inlet passage and the second annular pressure-sensing area;
• and the valve member loosely cooperating with the valve seat in the closed position so as to allow some leakage of water thereby, to enable the valve member to automatically reset itself to the normally open position when pressure applied thereto has been relieved.

A water flow fuse for automatically shutting off an excessive rate of flow of water in a system, comprising:

• a valve body having a water inlet passage and a water outlet passage in fluid communication with a valve seat opening;
• a first pressure-measuring passageway formed in the valve body and connected between the water inlet passage and a first pressure-sensing chamber;
• a dripper removably and sealingly held in the first pressure-measuring passageway to control flow of fluid therethrough;
• a combination poppet and sleeve valve member connected to a diaphragm moveble between a normally open position and a closed position against the valve seat opening;
• the combination poppet and sleeve valve member including a cylindrical, hollow element having two ends with a closed top protion formed at a first of the two ends, and a plurality of openings formed at a second of the two ends;
• the diaphragm sealingly connected between the valve body and the top closed portion of the combination poppet and sleeve valve member, downstream of the valve seat, above a guide element, so that a lower area of
• the diaphragm forms an annular fluid chamber downstream of the valve seat opening that is subject to varying pressures adjacent the water outlet passage, and a separate upper area of the diaphragm forms a portion of the first pressure-sensing chamber;
• a second pressure-measuring passageway formed in the body and connected between the fluid outlet passage and the annular fluid chamber between the guide element and the diaphragm;
• at least one spring cooperating with the combination poppet and sleeve valve member;
• and the combination poppet and sleeve valve member and the at least one spring being sized and dimensioned so that when a predetermined pressure differential is sensed, the combination poppet and sleeve valve member is moved from a full open position toward a closed position;
• and whereby, in the full open position, the plurality of openings formed at the second of the two ends communicates between a volume of water within said cylindrical, hollow element and an annular volume of water within the fluid chamber;
• and when in a partially closed position, the plurality of openings formed at the second of the two ends communicate upstream water pressure with downstream water pressure, while the slots are blocked by an enlarged head on the guide element, thereby slowing travel of the combination poppet and sleeve valve member toward the valve seat;
• and the combination poppet and sleeve valve member is finally moved to the fully closed position against the valve seat, without causing water hammer;
• after the slots are blocked;
• and
• the combination poppet and sleeve valve member loosely cooperating with said valve seat in said fully closed position so as to allow some leakage of water by the combination poppet and sleeve member, to enable the combination poppet and sleeve valve member to automatically reset itself to the normally open position when pressure applied thereto has been relieved.