Abstract:
A fluid regulating device comprises an actuator with upper and lower housing components. The upper and lower housing components are secured together at mating flanges via a plurality of fasteners. The upper housing component is formed with a vent to contain a relief valve, which exhausts fluid to the atmosphere under overpressure conditions. The upper housing component is constructed such that it does not require a pedestal or fins extending between the vent and the flange, which advantageously provides a completely unobstructed, continuous, ring-shaped flange for receiving and manipulating the fasteners during assembly and/or maintenance of the regulating device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The priority benefit of U.S. Provisional Patent Application No. 60/913,130, entitled “Service Regulator Vent,” filed Apr. 20, 2007, is claimed and the entire contents thereof are expressly incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to gas regulators, and more particularly, to gas regulators having relief valves for venting overpressure. 
       BACKGROUND 
       [0003]    The pressure at which typical gas distribution systems supply gas may vary according to the demands placed on the system, the climate, the source of supply, and/or other factors. However, most end-user facilities equipped with gas appliances such as furnaces, ovens, etc., require the gas to be delivered in accordance with a predetermined pressure, and at or below a maximum capacity of a gas regulator. Therefore, gas regulators are implemented into these distribution systems to ensure that the delivered gas meets the requirements of the end-user facilities. Conventional gas regulators generally include a closed-loop control actuator for sensing and controlling the pressure of the delivered gas. 
         [0004]    In addition to a closed loop control, some conventional gas regulators include a relief valve. The relief valve is adapted to provide over pressure protection when the regulator or some other component of the fluid distribution system fails, for example. Accordingly, in the event the delivery pressure rises above a predetermined threshold pressure, the relief valve opens to vent at least a portion of the gas to the atmosphere, thereby reducing the pressure in the system. 
         [0005]      FIG. 1  depicts one such conventional gas regulator  10 . The regulator  10  generally comprises an actuator  12  and a regulator valve  14 . The regulator valve  14  defines an inlet  16  for receiving gas from a gas distribution system, for example, and an outlet  18  for delivering gas to an end-user facility such as a factory, a restaurant, an apartment building, etc. having one or more appliances, for example. 
         [0006]    The actuator  12  is coupled to the regulator valve  14  to ensure that the pressure at the outlet  18  of the regulator valve  14 , i.e., the outlet pressure, is in accordance with a desired outlet or control pressure. The actuator  12  includes a housing  20  and a control assembly  22 . The housing  20  defines a cavity  21  containing at least a portion of the control assembly  22 . The control assembly  22  is adapted for sensing and regulating the outlet pressure of the regulator valve  14 . Specifically, the control assembly  22  includes a diaphragm  24 , a piston  32 , and a control arm  26  having a valve disc  28 . The control assembly  22 , and more particularly, the diaphragm  24  senses the outlet pressure of the regulator valve  14  and adjusts a position of the valve disc  28  to control the flow of fluid through the regulator valve  14 . 
         [0007]    More particularly, the diaphragm  24  is operably coupled to the control arm  26 , and therefore, the valve disc  28  via the piston  32 , and controls the opening of the regulator valve  14  based on the sensed outlet pressure. For example, when an end user operates an appliance, such as a furnace, for example, that places a demand on the gas distribution system downstream of the regulator  10 , the outlet flow increases, thereby decreasing the outlet pressure. Accordingly, the diaphragm  24  senses this decreased outlet pressure and moves the piston  32  and the right-side of the control arm  26  downward, relative to the orientation of  FIG. 1 . This displacement of the control arm  26  moves the valve disc  28  to open the regulator valve  14 . So configured, the appliance may draw gas toward the outlet  18  of the regulator valve  14 . 
         [0008]    In the conventional regulator  10  depicted in  FIG. 1 , the control assembly  22  further functions as a relief valve, as mentioned above. Specifically, the control assembly  22  also includes a relief spring  40  and a relief valve  42 . The relief valve  42  is disposed within a vent  34  formed integrally with the housing  20  of the actuator  12 . The diaphragm  24  includes an opening  44  through a central portion thereof and the piston  32  includes a sealing cup  38 . The relief spring  40  is disposed between the piston  32  and the diaphragm  24  to bias the diaphragm  24  against the sealing cup  38  to close the opening  44 , during normal operation. 
         [0009]    Upon the occurrence of a failure such as a break in the control arm  26 , the control assembly  22  is no longer in direct control of the valve disc  28  and inlet flow through the regulator valve  14  will move the valve disc  28  move into an extreme open position. This allows a maximum amount of gas to flow into the actuator  12 . Thus, as the gas fills the actuator  12 , pressure builds against the diaphragm  24  forcing the diaphragm  24  away from the sealing cup  38 , thereby exposing the opening  44 . The gas therefore flows through the opening  44  in the diaphragm  24  and toward the relief valve  42 . 
         [0010]    The relief valve  42  includes a valve plug  46  and a release spring  54  biasing the valve plug  46  into a closed position, as depicted in  FIG. 1 . Upon the pressure within the actuator  12  and adjacent the relief valve  42  reaching a predetermined threshold pressure, the valve plug  46  displaces upward against the bias of the release spring  54  and opens, thereby exhausting gas into the atmosphere through the vent  34  and reducing the pressure in the regulator  10 . In some embodiment, the vent  34  includes a plurality of internal threads  35  for being threadably connected to piping, to pipe the exhausted gas to a specific location. 
         [0011]    Depending on the particular application of the regulator  10 , the size of the vent  34  and the components of the relief valve  42  may vary. For example, applications requiring high capacity relief, may also require a higher capacity relief valve  42 . High capacity relief valves are typically constructed similar to the relief valve  42  discussed above, with the exception that they are larger in size. Thus, the size of the vent  34  must also be increased to accommodate the larger relief valve. 
         [0012]      FIG. 2  depicts an exterior of one conventional regulator housing  20  including a vent  34  configured to accommodate a low capacity relief valve, for example. The housing  20  includes an upper housing component  20   a  and a lower housing component  20 b. The upper housing component  20   a  includes a shell portion  51  and an integrally defines the vent  34 . The vent  34  includes a diameter, for example, of approximately 2 inches or less, for venting performance associated with the low capacity relief valve. Additionally, the upper and lower housing components  20   a,    20   b  include flanges  25   a,    25   b  extending around a perimeter thereof and which are secured together with a plurality of fasteners  36 . The number and spacing of the fasteners  36  is dictated by the design of the regulator  10  such that the flanges  25   a,    25   b  of the housing components  20   a,    20   b  can effectively compress and seal the diaphragm  24  depicted in  FIG. 1 , thereby minimizing the opportunity for leakage and ensuring optimal operation. The fasteners  36  conventionally include threaded fasteners such as hexagonal bolts and nuts, as depicted. 
         [0013]    The conventional housing components  20   a,    20   b  are manufactured with a casting process, wherein a plurality of mold cores are positioned relative to one another to cooperatively define a mold cavity. The mold cavity defines the specific geometry of the housing components  20   a,    20   b.  Due to the intricacies of casting, the upper housing component  20   a  of the conventional housing depicted in  FIG. 20  is formed with a pedestal portion  31  directly between the vent  34  and the flange  25   a.  The pedestal portion  31  of the upper housing component  20   a  depicted in  FIG. 2  is generally solid and disposed between a pair of adjacent fasteners  36 . Not only is the solid pedestal portion  31  a product of the manufacturing process, but it can also provide structural support to the portion of the vent  34  disposed above the flange  25   a  of the upper housing component  20   a.    
         [0014]    In contrast,  FIG. 3  depicts a partial exterior view of another conventional upper housing component  120   a  including a vent  134  configured to accommodate a high capacity relief valve. Thus, the vent  134  has a larger diameter than the vent  34  depicted in  FIGS. 1 and 2 , for example. The vent  134  may include a diameter of approximately 2 and ½ inches or more, for venting performance associated with the high capacity relief valve. Similar to the housing  20  discussed above, the upper housing component  120   a  depicted in  FIG. 3  includes a shell portion  151  and a flange  125   a  extending around the perimeter of the shell portion  151 . The flange  125   a  is adapted to be secured to a flange of a lower housing component (as shown in  FIG. 1 , for example) with a plurality of threaded fasteners  136 . 
         [0015]    Due to the increased size of the vent  134 , two of the fasteners  136   a,    136   b  must be positioned approximately below the vent  134  to provide a sufficiently uniform seal against the diaphragm that is disposed between the housing components. Accordingly, the upper housing component  120   a  depicted in  FIG. 3  does not include a solid pedestal, such as the pedestal portion  34  depicted in  FIG. 2 , but rather, a pair of fins  131   a,    131   b.    
         [0016]    The fins  131   a,    131   b  enable access to the flange  125   a  of the upper housing component  120   a  directly below the vent  134  such that the threaded fasteners  136   a,    136   b  may be installed to secure the housing components together. Additionally, as with the pedestal portion  31  described above with reference to  FIG. 2 , the fins  131   a,    131   b  can provide structural support to the portion of the vent  134  disposed above the flange  125   a  of the upper housing component  120   a.    
         [0017]    One shortcoming of the conventional designs of the upper housing components  20   a,    120   a  is that the pedestal portion  31  and fins  131   a,    131   b  tend to interfere with a technician tightening and/or loosening the threaded fasteners  36 ,  136   a,    136   b.  For example, as depicted in  FIG. 3 , a technician may use a wrench or other similar tool to tighten or loosen the fasteners  36  while assembling or disassembling the regulator  10 . The fins  131   a,    131   b  can interfere with the free movement of the wrench and therefore it may take longer to tighten or loosen the fasteners  136   a,    136   b.    
       SUMMARY 
       [0018]    The present invention provides a regulator comprising a regulator valve and an actuator. The actuator includes a housing that is coupled to the regulator valve and a control element for controlling the flow of gas through the regulator valve. The housing includes upper and lower components secured together about a peripheral flange with a plurality of threaded fasteners. The regulator also includes a relief valve for providing overpressure protection. The relief valve is disposed within a vent integrally formed within one of the housing components to enable gas to be exhausted to the atmosphere under overpressure conditions. The vent is sized and configured to minimize interference with installation and/or removal of the threaded fasteners. That is, the flange advantageously includes a completely unobstructed top surface for receiving a plurality of fasteners. 
         [0019]    In one embodiment, the vent is configured to accommodate a high capacity relief valve. 
         [0020]    Another aspect of the present invention provides a mold for manufacturing a housing component of an actuator of a regulator for accommodating a high capacity relief valve. The mold comprises a plurality of mold cores cooperatively defining the housing component including a peripheral flange and a vent. The flange advantageously includes a completely unobstructed top surface for receiving a plurality of fasteners. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is a side cross-sectional view of a regulator; 
           [0022]      FIG. 2  is a perspective view of one conventional regulator housing including a vent for accommodating a low capacity relief valve; 
           [0023]      FIG. 3  is a partial perspective view of another conventional regulator housing including a vent for accommodating a high capacity relief valve; and 
           [0024]      FIG. 4  is a partial perspective view of a regulator housing constructed in accordance with the principles of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]      FIG. 4  depicts an exterior view of a regulator housing  220  including a vent  234  constructed in accordance with the principles of the present invention and configured to accommodate a high capacity relief valve, for example. To accommodate a high capacity relief valve, the vent  234  can include a diameter, for example, of approximately 2 and ½ inches or more. The housing  220  depicted in  FIG. 4  may also be adapted, however, to accommodate a low capacity relief valve and, as such, can have a diameter less than 2 and ½ inches. Moreover, the housing  220  is adapted for use with the regulator discussed above with reference to  FIG. 1 . 
         [0026]    Similar to the conventional housings  20 ,  120  discussed above with reference to  FIGS. 1-3 , the housing  220  of the present embodiment of the dsclosure includes an upper housing component  220   a  and a lower housing component (not shown), which may be similar to the lower housing component  20   b  disclosed with reference to  FIG. 1 . 
         [0027]    The upper housing component  220   a  integrally defines a shell portion  251 , the vent  234 , and a flange  225 . The flange  225  extends completely around the perimeter of the shell portion  251  of the upper housing component  220   a  and is adapted to be secured to a corresponding flange of a lower housing component such as flange  25   b  of the lower housing component  20   b  depicted in  FIG. 1 . For this purpose, the flange  225  includes a plurality of apertures  237  for receiving a plurality of fasteners  236 . The fasteners  236  secure the upper housing component  220   a  to a lower housing component such as the lower housing component  20   b  depicted in  FIG. 1 , for example. 
         [0028]    The number and spacing of the fasteners  236  is dictated by the design of the regulator such that the housing  220  effectively compresses and seals a diaphragm, such as the diaphragm  24  depicted in  FIG. 1 , between the flanges of the upper and lower housing components to minimize leakage and ensure optimal operation of the regulator. The fasteners  236  conventionally include threaded fasteners such as hexagonal bolts and nuts. 
         [0029]    The flange  225  of the upper housing component  220   a  of the present embodiment includes a top surface  225   a  and a bottom surface  225   b  and, as mentioned, extends completely around the perimeter of the upper housing component  220   a.  In the disclosed embodiment, the upper housing component  220   a  can include a circular cross-section. Therefore, the flange  225  can comprise a circumferential flange extending around the circumference of the upper housing component  220   a.  The bottom surface  225   b  of the flange  225  is adapted to sealingly engage a peripheral portion of a diaphragm such as the diaphragm  24  depicted in  FIG. 1 . The top surface  225   a  is a continuous, completely unobstructed, ring-shaped surface that provides a surface, against which hexagonal heads  236   a  of the plurality of fasteners  236  abut. So provided, the entire top surface  225   a  of the flange  225  defines a seating surface for the fasteners  236 . 
         [0030]    The vent  234  of the upper housing component  220   a  depicted in  FIG. 4  comprises a generally L-shaped conduit that provides for fluid communication from within the housing  220 , as depicted in  FIG. 1 , and the atmosphere to exhaust fluid and provide overpressure protection under overpressure conditions in a manner similar to that described above with reference to the regulator  10  depicted in  FIG. 1 . The vent  234  of the present embodiment includes a generally hollow elbow (as shown in  FIG. 1 , for example) and is formed integrally, i.e., as one-piece, with the upper housing component  220   a.  The vent  234  includes an upright portion  234   a  and a coupling portion  234   b  disposed approximately perpendicular to each other. The upright portion  234   a  extends generally upward from the shell portion  251  of the upper housing component  220   a.  The coupling portion  234   b  extends from the upright portion  234   a  and over the top surface  225   a  of the flange  225 , and spaced from the top surface  225   a  of the flange  225 . Said another way, the coupling portion  234   b  is cantilevered from the upright portion  234   a  such that a portion of the coupling portion  234   b  is disposed unsupported above the top surface  225   a  of the flange  225 . The coupling portion  234   b  includes a generally cylindrical outer surface  243  and defines an opening  240 . The opening  240  is in direct communication with the atmosphere. The opening  240  is circular in cross-section and may be adapted to be coupled to piping such that exhaust from the vent  234  may be piped to a specific location. Thus, in one embodiment, an internal cylindrical surface  241  of the opening  240  may include a plurality of threads (not shown) adapted for threaded engagement with a threaded pipe or other pipe fitting. Therefore, the cylindrical surface  241  of the embodiment depicted in  FIG. 4  can include a number of threads sufficient to threadably engage a pipe or other threaded coupling of approximately 2 and ½ inches or more. 
         [0031]    As mentioned, the coupler portion  234   b  of the vent  234  includes a cylindrical outer surface  243 . This cylindrical outer surface  243  is generally uniformly cylindrical between the opening  240  and the upright portion  234   a  of the vent  234 . So configured, the coupling portion  234   b  does not include a pedestal, or fins, such as the pedestal portion  31  and fins  131   a,    131   b  of the conventional housing components  20   a,    120   a  disclosed above with reference to  FIGS. 1-3 . Thus, the top surface  225   a  of the flange  225  of the upper housing component  220   a  of the present embodiment is completely unobstructed, which advantageously enables uninterrupted and unfettered access to every head  236   a  of every fastener  236  disposed about the flange  225   a  of the upper housing component  220   a.  This advantageously allows a technician to more quickly assemble or disassemble an actuator housing of a regulator constructed in accordance with the principles of the present discosure during the initial build, or subsequently, during field service to replace a diaphragm, a spring, or any other component. 
         [0032]    The housing component  220   a  depicted in  FIG. 4  may be manufactured by machining, casting, injection forming, or generally any other method. However, in utilizing a casting method of manufacturing, such casting would include a plurality of cores, each core defining a recess. So configured, positioning each of the cores relative to each other, the recesses in the cores cooperatively define a cavity which defines the specific geometry of the housing component  220   a.  Specifically, in one embodiment, the plurality of cores could come together to define a parting line that defines the specific geometry of the vent  234  and, particularly a parting line that conforms to line  300  depicted in  FIG. 4 . So configured, the core or cores conforming to the parting line  300  would advantageously define a cavity for the housing  220   a  which does not require the inclusion of a space for a pedestal portion or fins to be formed adjacent to the vent  234 . 
         [0033]    While the housing component  220   a  depicted in  FIG. 4  has been described as enabling unobstructed access to the fasteners  236  by eliminating the pedestal portion and fins described above with reference to  FIGS. 2 and 3 , respectively, an alternative embodiment the housing component  220   a  can include a flange  225  having an enlarged radial dimension. In such an embodiment, the pedestal portion or fins may not have to be eliminated. For example, by increasing the radial dimension of the flange  225 , the apertures  237  for receiving the fasteners  236  can be moved radially outward such that the fasteners would no longer be interfered with by a pedestal portion or fins. In this alternative embodiment, the top surface  225   a  of the enlarged flange  225  still has a continuous, and completely unobstructed, ring-shaped portion disposed radially outward of the coupling portion  234   b  of the vent  234  to provide a seating surface for the fasteners  236 . So configured, it is just this outward-most radial portion of the top surface  225   a  of the flanges  225  that constitutes the seating surface for the fasteners  236 . 
         [0034]    Thus, the present invention is not limited to the specific embodiment(s) disclosed herein, but rather, is intended to be defined by the spirit and scope of the following claims and any and all equivalents thereof.