Patent Publication Number: US-6907940-B1

Title: Fast response fluid flow control valve/nozzle

Description:
STATEMENT OF GOVERNMENT INTEREST 
   The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without payment of any royalties thereon or therefor. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to high-speed fire protection/suppression systems and, more particularly, to fast response fluid flow control nozzles incorporating a frangible element that is designed to be ruptured to release said material. 
   2. Description of the Background 
   The ongoing development of increasingly hazardous (i.e. energetic or explosive) materials requires concurrent improvements in the safety systems associated with their handling and storage. High-speed fire protection/suppression systems represent one of the most important safety systems associated with those evolving materials. High-speed fire protection/suppression systems take a number of forms. Common forms include (1) fixed pipe pilot-actuated spraying/sprinkler systems incorporating poppet valve-based nozzle assemblies and (2) pressurized containers of fire extinguishing/suppressing material (e.g. water) in combination with some means of fire detection. As one might expect, both forms possess certain pros and cons. 
   Pressurized containers have been historically used for the discharge of fire suppression agents in explosion suppression systems. Testing conducted by the Fire Research Laboratory at Tyndall Air Force Base has demonstrated that a pressurized container-based system, in this case a spherical container, can provide a significantly faster response time, in discharging a fire extinguishing/suppressing material to control various fire-related hazards, than a pilot-actuated spraying/sprinkler system. However, the limited, or finite, volume of fire extinguishing/suppressing material present in a pressurized container-based system, as opposed to the essentially unlimited supply available with a fixed pipe pilot-actuated spraying/sprinkler system, can be problematic. Additional deficiencies of pressurized container-based systems include (1) their typically bulky size/shape, (2) the significant cost and effort required to rearm/refill them, (3) their inability to be utilized/deployed in areas of limited size or accessibility, and (4) their initial purchase price. 
   The fast response time of a pressurized container-based system is generally provided by a fluid flow control valve incorporating a frangible element (e.g. a disc) and some means for rupturing that element upon the detection of a fire. The present invention is not the first to address the issue of fast response fluid flow control devices for fire protection/suppression systems. For example, U.S. Pat. No. 5,647,738 to Chatrathi et al., U.S. Pat. No. 5,458,202 to Fellows et al., U.S. Pat. No. 5,232,053 to Gillis et al., U.S. Pat. No. 5,031,701 to McLelland et al., U.S. Pat. No. 4,006,780 to Zehr, and U.S. Pat. No. 3,834,463 to Allard et al. disclose a variety of means for releasing the flow of a fire extinguishing/suppressing material via the rupturing of a frangible element. 
   U.S. Pat. No. 5,647,438 to Chatrathi et al. discloses an explosion suppressant dispersion nozzle for dispersing suppressant material from a pressurized suppressant storage vessel to a protected zone or room upon the rupturing of a frangible element by an actuator. 
   U.S. Pat. No. 5,458,202 to Fellows et al. discloses a pressurized extinguishant release device with a penetrator affixed to a rolling diaphragm. The penetrator is positioned above a frangible membrane that encloses a pressurized extinguishant. Heating of a liquid filled sensor tube to a certain temperature will cause vapor pressure to push against the diaphragm, causing a shear pin to fail, and propel the penetrator into the membrane and thus allow the extinguishant to flow. 
   U.S. Pat. No. 5,232,053 to Gillis et al. discloses an explosion protection system including a container with a discharge outlet adapted to contain an explosion suppressant under pressure, a frangible member covering the discharge outlet, an explosive charge disposed in the container adjacent to the frangible member and adapted to create explosive forces that rupture said member, and a somewhat compressible explosion suppressant retained under pressure. 
   U.S. Pat. No. 5,031,701 to McLelland et al. discloses a suppressant delivery and release nozzle structure for an explosion protection system. The nozzle is a reducing elbow, concentric or eccentric mounting a rupture disc at its small end. A selectively actuatable detonator housed in the nozzle adjacent the disc permits substantially instantaneous opening of the disc upon command for release and delivery of suppressant to a zone to be protected from an explosion hazard. 
   U.S. Pat. No. 4,006,780 to Zehr discloses a device for rupturing a pressurized cylinder containing a fire extinguishing product. When the temperature is high enough to melt a fusible link, a spring-loaded punch is forcibly propelled downwardly to rupture a frangible disc in the cylinder to allow the contents to be discharged. 
   U.S. Pat. No. 3,834,463 to Allard et al. discloses a sensitive sprinkler that includes a rupture disc valve positioned to block fluid flow through the flow path. An explosive squib is mounted in the fluid flow path upstream of the rupture disc so that when exploded an expansive gas directs a pressure through said fluid to rupture the disc. A fire detector assembly electrically activates the squib substantially immediately upon detection of a fire. 
   The ideal fire protection/suppression system would combine the fast response of a container-based system with the essentially unlimited extinguishing/suppressing material supply of a fixed pipe system. Unfortunately, due to the nature of fixed pipe fire protection/suppression systems, each of these prior art devices possesses certain limitations with respect to the specific needs addressed by the present invention. The Chatrathi et al., Gillis et al., McLelland et al., and Allard et al. patents incorporate the storage and use of an explosive device/detonator to rupture the frangible element. The use of any explosive device/detonator does provide the required activation speed of a system, however the type and size of the device being considered is essential as it may be exposed to highly energetic/explosive materials. Additionally, the Gillis et al. and Allard et al. patents operate in a manner that generates an omni-directional pressure wave that momentarily disrupts the outward flow of the fire suppressing material. With highly energetic/explosive materials, every fraction of a second counts and, therefore, any process that delays the outward flow of the fire suppressing material is one that must be eliminated. The Fellows et al. and Zehr patents disclose components used to rupture the frangible elements that are positioned within the flow pathway for the fire extinguishing/suppressing material. This configuration, in a best case scenario, results in a marginal occlusion of the orifice through which the fire extinguishing/suppressing material is meant to flow. In a worst case scenario, the orifice might become completely occluded. 
   Therefore, there remains a need for a fast response fluid flow control valve/nozzle incorporating a frangible element that is designed to be ruptured to release fire suppressant material from an essentially unlimited supply. While the use of an explosive or energetic actuator may be required to provide the required speed of activation of a system, significant consideration should be given to reducing the potential hazard. The fluid flow control valve/nozzle should also be scalable to provide for use in a variety of applications, fabricated of materials that provide the durability/longevity required by the nature of its use, capable of being retrofitted to existing fire protection/suppression systems, and economical to manufacture in order to provide for widespread use. 
   SUMMARY OF THE INVENTION 
   It is, therefore, the primary object of the present invention to provide a fast response fluid flow control valve/nozzle for use in high-speed fire protection/suppression systems of the type having an essentially unlimited supply of fire extinguishing/suppressing materials. 
   It is another object of the present invention to provide a fast response fluid flow control valve/nozzle with frangible element that cannot block, to any degree, the flow of the fire extinguishing/suppressing materials. 
   Yet another object of the present invention is to provide a fast response fluid flow control valve/nozzle with a frangible element for use in high-speed fire protection/suppression systems that controls and significantly reduces the hazard introduced by the actuator into the protected area to break the frangible element. 
   It is another object of the present invention to provide improved fast response fluid flow control valves/nozzles for use in high-speed fire protection/suppression systems that are scalable to provide for use in a variety of applications. 
   Another object of the present invention is to provide improved fast response flow control apparatus for use in high-speed fire protection/suppression systems that are fabricated of materials that provide the durability/longevity required by the nature of its use. 
   Yet another object of the present invention is to provide improved fast response flow control apparatus that may be retrofitted to existing fire protection/suppression systems. 
   Still another object of the present invention is to provide improved fast response flow control apparatus for use in high-speed fire protection/suppression systems that are economical to manufacture to provide for widespread use. 
   These and other objects are accomplished by a fast response fluid flow control valve/nozzle that generally comprises an assembly of six primary components. A chamber base provides a threaded connection for a typical high-speed fire protection/suppression piping system. The base forms one half of a chamber that is pressurized by the initiation of a commercially available actuation device that is connected to a port in the side of the base. A jet core is threaded into the chamber base to form the other half of the chamber. The jet core includes the channels connecting the chamber with the under side of a rupture (i.e. frangible) disc assembly. A disc retention ring holds the rupture disc assembly against the jet core. A nozzle port threads onto the chamber base applying the pressure to the disc retention ring to seat the rupture disc assembly and tie the components together as a complete assembly. The nozzle port also provides a threaded connection to facilitate the installation of a water spray nozzle. The final component is a pressure cartridge actuator threaded into the chamber base and used to generate the pressure required to rupture the disc assembly. 
   The fast response fluid flow control valve/nozzle according to the present invention combines the technology used to rupture the frangible discs found in pressurized container-based fire protection/suppression systems with that found in fixed pipe, high-speed spray/sprinkler systems. The present invention applies over-pressurization technology to a significantly smaller chamber contained within the fast response fluid flow control valve/nozzle that is virtually isolated from the essentially unlimited supply of fire extinguishing/suppressing material. The apparatus&#39; design directs the over-pressurization created in the chamber through the channels in the jet core to create a small, localized pressure wave on the underside of the frangible disc. The pressure wave is, due to its localized nature, sufficient to rupture the disc in an extremely rapid manner without generating any flow disrupting back pressure that would delay the discharge of the fire extinguishing/suppressing material through the fast response fluid flow control valve/nozzle. 
   The present invention fulfills its purpose while significantly limiting the introduction of hazards (e.g. explosive devices) into the area it protects. The present invention is scalable to provide for use in a variety of applications, fabricated of materials that provide the durability/longevity required by the nature of its use, capable of being retrofitted to existing fire protection/suppression systems, and economical to manufacture in order to provide for widespread use. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments and certain modifications thereof when taken together with the accompanying drawings in which: 
       FIG. 1  is a side, cross-sectional view of a fast response fluid flow control valve/nozzle  10  according to a preferred embodiment of the present invention. 
       FIG. 2  is an exploded view of the fast response flow control valve/nozzle  10  as in  FIG. 1 . 
       FIG. 3  is a side, cross-sectional view of a chamber base  20 . 
       FIG. 4  is an end perspective view of the chamber base  20  as in  FIG. 3 . 
       FIG. 5  is a composite front view (B) and side, cross-sectional view (A) of a jet core  30 . 
       FIG. 6  is a composite front view (A) and side, cross-sectional view (B) of a retention ring  50 . 
       FIG. 7  is a composite side, cross-sectional view (B) and end perspective view (A) of a nozzle port  60 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1 and 2  are, respectively, side cross-sectional and exploded views of a fast response fluid flow control valve/nozzle  10  according to a preferred embodiment of the present invention. The fast response fluid flow control valve/nozzle  10  generally comprises a chamber base  20 , a jet core  30 , a frangible disc  40 , a disc retention ring  50 , a nozzle port  60 , a plurality of o-rings  70 – 73 , and a pressure cartridge  75 . 
   As can be seen in  FIGS. 3 and 4 , the chamber base  20  comprises a base and outer walls of a chamber  21  of varying diameters, internal threads  22 A at one end, internal threads  22 B and external threads  23  at the opposite end, an actuator mounting port  24 , an air bleed port  26 , a plurality of key pin holes  29  formed in the end  28  proximate the external threads  23 , and an o-ring groove  34 . The actuator mounting port  24  and the air bleed port  26  are in fluid communication with the internal chamber  21  and positioned 180E apart on the external surface near the end with the internal threads  22 A. The internal threads  22 A represent the means (i.e. a fire suppressant inlet port  80 —see  FIG. 1 ) for creating a threaded connection between the valve/nozzle  10  and a typical high-speed fire protection/suppression piping system (not shown in the Figures). A hexagonal cross-section  25  is formed in the external surface of the chamber base  20 , at the end that includes the internal threads  22 A, to further facilitate the making of the aforementioned threaded connection. The chamber base  20  is preferably fabricated of commercially available, round stainless steel stock. However, other strong, yet lightweight, materials such as titanium may be utilized. 
     FIG. 5  is a composite front view (B) and side, cross-sectional view (A) of a jet core  30 . The jet core  30  comprises a central bore  31 , external threads  32  at one end  38 , an o-ring groove  35  formed in its external surface  36 , and a plurality of channels  37  formed to provide fluid communication between the external surface  36  and the end  38  proximate the external threads  32 . The jet core  30  is preferably fabricated of commercially available, round stainless steel stock. However, other strong, yet lightweight, materials such as titanium may be utilized. 
   As shown in  FIG. 2 , the frangible disc  40  is preferably a rupture disc assembly commercially available from the Oklahoma Safety Equipment Company (OSECO) of Broken Arrow, OK. The disc assembly  40  generally comprises a stainless steel spherically curved disc  42  and a base  41  formed from two stainless steel rings  44 ,  45 . The rings  44 ,  45  and disc  42  are fixedly attached (e.g. welded) in order to form the finished assembly  40 . The disc assembly  40  is designed to rupture at a pressure of 300 PSI (OSECO&#39;s disc design provides for rupture pressures from 160 to 4,000 PSI as specified). Ring  44  includes an o-ring groove  46  to assist in providing a water-tight seal between the disc assembly  40  and the jet core  30 . 
     FIG. 6  is a composite front view (A) and side, cross-sectional view (B) of a retention ring  50 . The disc retention ring  50  comprises a central bore  51 , an o-ring groove  55  formed in its external surface  53 , and a plurality of key pins  52  seated (e.g. press or friction fit) around the periphery of one end  56 . The disc retention ring  50  is preferably fabricated of commercially available, round stainless steel stock. However, other strong, yet lightweight, materials such as titanium may be utilized. 
     FIG. 7  is a composite side, cross-sectional view (B) and end perspective view (A) of a nozzle port  60 . The nozzle port  60  comprises a central bore  61  of varying diameters and internal threads  62 ,  63  at both ends. The smaller diameter internal threads  62  represent the means for creating a threaded connection (i.e. a fire suppressant discharge port  90 —see  FIG. 1 ) between the valve/nozzle  10  and the spray/dispersion nozzle used in a typical high-speed fire protection/suppression system (not shown in the Figures). A hexagonal cross-section  64  is formed in the external surface of the nozzle port  60 , at the end that includes the smaller diameter internal threads  62 , to further facilitate the making of the aforementioned threaded connection. The nozzle port  60  is preferably fabricated of commercially available, round stainless steel stock. However, other strong, yet lightweight, materials such as titanium may be utilized. 
   As shown in  FIGS. 1 and 2 , the pressure cartridge actuator  75  is preferably a device commercially-available from McCormick Selph, Inc. of Hollister, CA under part no. 817444-5. Upon actuation, the cartridge  75  generates a pressure in excess of 300 PSI within the chamber base  20  and the channels  37  of the jet core  30  in order to rupture the disc assembly  40 . 
   With collective reference to  FIGS. 1–7 , the fast response fluid flow control valve/nozzle  10  is assembled as follows. The two commercially-available o-rings  70 ,  71  are placed in the o-ring grooves  34 ,  35 , respectively, found in the chamber base  20  and on the external surface  36  of the jet core  30 . The jet core  30  is inserted into the internal chamber  21  of the chamber base  20  such that its external threads  32  engage the base&#39;s internal threads  22 B. The chamber base  20  and jet core  30  are thus screwed together until the smaller o-ring  70  engages the leading end  33  of the jet core  30  and the larger o-ring  71  engages an angled internal surface  27 A of the base  20 . The base  41  of the disc assembly  40  is placed in position against an internal face  54  of the retention ring  50  such that its spherical surface  42  curves toward the face  54 . O-rings  72 ,  73  are placed in grooves  55 ,  46 , respectively. The combination of the retention ring  50 , disc assembly  40 , and o-rings  72 ,  73  is attached in a releasable manner to the previously created sub-assembly of the chamber base  20  and jet core  30  by aligning and engaging the plurality of key pins  52  on the retention ring  50  with the plurality of holes  29  formed in the chamber base  20 . The joining of these components serves to compress o-ring  73  within groove  46  against end surface  38  of the jet core  30  and to engage o-ring  72  with an internal surface  27 B of the chamber base  20 , thereby trapping the disc assembly  40  between the core  30  and the ring  50 . The nozzle port  60  is attached to the resulting sub-assembly by engaging the internal threads  63  of the nozzle port  60  with the external threads  23  of the chamber base  20 . Finally, the cartridge actuator  75  is attached in a releasable manner to the chamber base  20  via the internal threads  76  located within the mounting port  24 . 
   The operation of the valve/nozzle  10 , after its installation in a typical fixed pipe high-speed fire protection/suppression system, once any entrapped air is removed from the chamber through bleed port  26  (a conventional bleeder valve can be used for this purpose but is not shown in Figures), is as follows. The valve/nozzle assembly  10  contains an internal chamber  12  that is pressurized to more than 300 PSI by the initiation of the cartridge actuator  75  upon the detection of a fire/explosion. The pressure wave created by the actuator&#39;s initiation is directed through the channels  37  and against the underside (i.e. convex) surface  42  of the frangible disc  40  in order to rupture the disc  40  and release the fire extinguishing/suppressing material that enters through inlet port  80  and exits through a dispersing nozzle attached to discharge port  90 . 
   As is readily perceived in the foregoing description, the fast response fluid flow control valve/nozzle  10  of the present invention combines the technology used to rupture the frangible discs found in container-based fire protection/suppression systems with that found in fixed pipe, high-speed spray/sprinkler systems. The present invention applies over-pressurization technology to a significantly smaller chamber  12  contained within the fast response fluid flow control valve/nozzle  10  that is virtually isolated from the essentially unlimited supply of fire extinguishing/suppressing material. The design of the valve/nozzle  10  directs the over-pressurization created in the chamber  12  through the channels  37  in the jet core  30  to create a small, localized pressure wave on the underside of the frangible disc assembly  40 . The pressure wave is, due to its localized nature, sufficient to rupture the disc assembly  40  in an extremely rapid manner without generating any flow disrupting back pressure that would delay the discharge of the fire extinguishing/suppressing material through the fast response fluid flow control valve/nozzle  10 . The present invention is scalable to provide for use in a variety of applications, fabricated of materials that provide the durability/longevity required by the nature of its use, capable of being retrofitted to existing fixed pipe fire protection/suppression systems, and economical to manufacture in order to provide for widespread use. 
   Having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It is to be understood, therefore, that the invention may be practiced otherwise than as specifically set forth in the appended claims.