Abstract:
A regulator for controlling the pressure of flowing fluid and also for selectively fully enabling or stopping the flow. The regulator valve includes a valve housing having an inlet passage and an outlet passage connected by a flow passage with a seat surrounding the flow passage. A valve member is movable toward and away from contact with the seat. A control housing is attached to the valve housing. An elongated rod connected at one end to the valve member has an opposite end extending into the control housing. A rod piston is connected to the opposite end of the elongated rod and is movable in the control housing in sealing engagement with the walls thereof. A compression spring is provided to bias the rod piston and the valve member in directions either toward or away from sealing engagement with the flow passage seat. An auxiliary piston is positioned in the control housing on the side of the rod piston away from the seat. An extender is formed on the auxiliary piston and is engageable with the rod piston to maintain a minimum spacing between the rod piston and the auxiliary piston. Alternately a cup-shaped member with an extender could be on the rod piston. First and second ports and a vent port are formed in the control housing and can be alternately connected by conduits to deliver pressure to move the valve member toward or away from the valve seat. A solenoid operated control valve or similar device is positioned in the conduit leading from the inlet passage for controlling the flow of fluid in this conduit.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates to a fluid flow control device that combines the functions of pressure regulation and selectable flow control. That is, the device regulates the pressure at the outlet to a predetermined value and it responds to a suitable control signal to permit or prevent fluid flow. The device will be referred to herein as a regulator valve. The device is particularly suitable for use in irrigation applications, although it is not limited to this use.  
           [0002]    Agricultural irrigation systems typically have a main pipeline and multiple secondary and tertiary distribution lines branching therefrom. Water (with or without added fertilizer, herbicide, insecticide etc.) is supplied to the end of the pipeline. Sprinkler heads, branch laterals, or other distribution means are mounted at intervals along the length of the pipeline for distributing the water. The sprinkler heads or other distribution means can be mounted more or less directly to the main pipeline or at some point along the length of branch distribution laterals that supply the water application devices for growing the crops. In either case the flow rate of water through a sprinkler head or other application device is dependent on the hydraulic pressure at the inlet of the device. That pressure can vary along the length of the pipeline due to friction losses in the pipe and undulations in the local terrain. When it is critical to control the flow rate through an application device a pressure regulator is placed between the pipeline and the device to assure a known hydraulic pressure at the device&#39;s inlet, regardless of its location along the length of the distribution system or undulations in the local terrain. A typical pressure regulator of this type is shown in U.S. Pat. No. 4,543,985.  
           [0003]    In some applications it may be also desirable to be able to turn the flow of individual application devices on or off, in addition to controlling the pressure seen by the inlet of the device. Examples where this would be advantageous include a center pivot machine having a swing span pivotably connected to the moving end of the pipeline. The swing span swings into the corners of a field to irrigate portions that would otherwise be missed by the circular pattern covered by the main pipeline. The swing span folds in when the main pipeline is opposite an edge of the field and swings out into a corner. U.S. Pat. Nos. 4,011,990 and 5,695,129 describe such a machine. The main pipeline may stop while the swing span irrigates the corner portion. In that case, it would be desirable to turn off the main pipeline sprinklers. The swing span sprinklers need to be off when the swing span is not irrigating a corner. Another example where on-off control is desirable is where field conditions are known to vary from one location to another and the irrigation machine is programmed to apply water and/or chemicals at differing rates dependent on these known field conditions. A third example of where on-off control is desirable is in an orchard, vineyard, golf course, or other application, where it is desirable to turn on or off only a portion of the distribution devices or branch distribution laterals that supply the water application devices connected to a supply system.  
           [0004]    My prior combined pressure regulator and shut-off valve, which is shown and described in U.S. Pat. No. 6,374,853, incorporates a selectable on-off feature. This prior valve of mine utilizes first and second tubular plungers each connected to first and second flexible diaphragms, respectively. This valve is particularly well suited to installation in the tubular drop that connects a sprinkler head to a main or branch pipeline wherein the valve functions as a normally open valve.  
         SUMMARY OF THE INVENTION  
         [0005]    The present invention is directed to a combined pressure regulator and shut-off valve that can be installed in a main or a branch pipeline utilizing a disk valve or similar device and an annular seat. The pressure regulating and shut-off mechanisms for the valve are installed in a separate control housing which may be attached to the pipeline shut-off valve housing by a threaded connection, tie bolts or other suitable means of retention. Alternately the control housing could be integrally molded with the valve. A balancing pressure piston located in the control housing is fixedly connected to the disk valve by a rod or a stem. A shut-off piston is movable freely in the control housing relative to the balancing pressure piston attached to the rod. The shut-off piston is equipped with a standoff which engages the balancing pressure piston to maintain a chamber of a minimum length between the two pistons.  
           [0006]    In one embodiment of the invention, a compression spring is positioned between the balancing pressure piston and an end wall of the control housing to enable the valve to function as a “normally open” valve. In another embodiment of the invention, a compression spring is installed between the balancing pressure piston and the shut-off piston to enable the valve to function as a “normally closed” valve. The use of a shut-off piston which moves relative to the balancing pressure piston in a chamber of a minimum length between the pistons allows the placement of ports in the control housing to permit the shut-off pressure and regulating pressure conduits to be connected to the various ports in different arrangements to obtain varying operating functions for the combined pressure regulating and shut-off valve. The shut-off or pilot pressure is usually controlled by a solenoid operated valve or similar device which may be of the self-bleeding type to relieve pressure in the shut-off pressure conduit when the solenoid operated valve is closed while the regulating conduit is usually unobstructed. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    The invention is illustrated more or less diagrammatically in the following drawings wherein:  
         [0008]    [0008]FIG. 1 is a cross sectional view taken through one embodiment of the valve of this invention shown in its open pressure regulator condition;  
         [0009]    [0009]FIG. 2 is a view similar to FIG. 1 but showing the valve in a shut-off condition;  
         [0010]    [0010]FIG. 3 is a cross sectional view of another embodiment of the invention showing the valve in its open pressure regulating condition;  
         [0011]    [0011]FIG. 4 is a view similar to a view of the valve of FIG. 3 but showing the valve in its shut-off position;  
         [0012]    [0012]FIG. 5 is a cross sectional view of a third embodiment of the valve of this invention showing the valve in its normally closed position;  
         [0013]    [0013]FIG. 6 is a view of the embodiment of the valve of FIG. 5 but shown in a fully open position;  
         [0014]    [0014]FIG. 7 is a similar view of the valve of FIG. 5 but showing the valve in its open pressure regulating position;  
         [0015]    [0015]FIG. 8 is a cross sectional view of a fourth embodiment of the valve of this invention showing the valve in its normally closed position;  
         [0016]    [0016]FIG. 9 is a view of the valve of FIG. 8 shown in its fully open position;  
         [0017]    [0017]FIG. 10 is a view of the embodiment of the valve of FIG. 8 but shown in its open pressure regulating position;  
         [0018]    [0018]FIG. 11 is a cross sectional view of a fifth embodiment of the valve of the invention shown in its normally closed position;  
         [0019]    [0019]FIG. 12 is a cross sectional view of a sixth embodiment of the invention showing the valve in its normally closed position;  
         [0020]    [0020]FIG. 13 is a view of the valve of FIG. 12 shown in a pressurized, closed condition;  
         [0021]    [0021]FIG. 14 is a cross sectional view of the valve of the embodiment of FIG. 12 shown in its open pressure regulating position; and  
         [0022]    [0022]FIG. 15 is a cross-sectional view of a seventh embodiment of the valve of this invention showing the valve in its open pressure regulating condition. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0023]    The regulator valve  21  of this invention is shown generally in FIG. 1 of the drawings. It includes a housing  23  having an inlet passage  25  and an outlet passage  27 . The valve can be installed in a main or branch pipeline of an agricultural irrigation system or may be installed in the supply line that connects a sprinkler head or other application device to such a main or branch pipeline. The inlet and outlet passages are separated by a partition  29  in which there is a water flow opening or passage  31 . As is conventional, an annular seat  33  surrounds the opening. This seat may be formed as part of the valve housing  23  or may be a removable and replaceable seat of the type commonly known in the plumbing industry. The passage  31  defines an upstream side and a downstream side of the pipeline. The upstream side is that portion from the passage  31  toward the inlet  25  and includes the pipeline (not shown) attached to valve housing at the inlet passage as well as the inlet passage itself. The downstream side is that portion from the passage  31  toward the outlet  27  and includes the pipeline (not shown) attached to the valve housing at the outlet passage as well as the outlet passage itself. A chamber  35  is located between the water flow opening  31  and the outlet passage  27 . A wall  37  is formed at what can be called the bottom of the chamber  35  in accordance with the orientation shown in FIG. 1 of the drawings but it should be appreciated that this orientation is for ease of description and the valve housing  23  can be oriented in other directions. A small passage or opening  39  is formed in the wall  37  of the housing  23 . The wall  37  may be omitted and the top wall of the control housing, to be hereinafter explained, may function to close the bottom of the chamber  35 .  
         [0024]    A control housing  41 , which is generally cylindrical in shape, has a generally circular top wall  43  which fits against the bottom of the housing  23 . A collar  45  formed as part of the top wall  43  extends into the opening  39  in the housing  23 . The control housing has a tubular wall  49  which is preferably cylindrical in shape and an end or bottom wall  51  which is located oppositely to the wall  43 . The control housing is shown to be supported on the valve housing by tie bolts and nuts  55  although other fastening arrangements may be used.  
         [0025]    A port  61  is formed in the housing  23  leading into the inlet passage  25 . A port  63  is formed in the housing  23  leading into the outlet passage  27 . Two ports are formed in the tubular wall  49  of the control housing  41 . One of these, which is closer to the top wall  43 , is designated as the upper port  65  and the other port  67 , which is located closer to the bottom wall  51  of the control housing, is designated the lower port  67 . A third port  69  is formed in the bottom wall  51  of the control chamber.  
         [0026]    Although various manners of controlling water flow through the opening  31  may be utilized, for illustrative purposes a disk valve is shown. The disk valve  71  is located in the chamber  35  of the housing  23  and it has a compressible seal  73  which can be moved into and out of water sealing contact with the annular seat  33  of the housing. The disk valve is affixed to a stem  75  which extends through the opening  47  in the collar  45  of the control housing top wall  43  and into the control housing  41 . A disk-shaped piston  77  is affixed to the other end of the stem  75  and an annular seal such as an O-ring  79  is mounted on the periphery of the piston to engage the tubular wall  49  of the control housing. It should be understood that a piston is only one form of a partition that may be used to sub-divide the control housing  41  to isolate the ports from one another. A compression spring  81  is positioned between the top wall  43  of the control housing  41  and the piston  77  of the disk valve to bias the disk valve  71  out of contact with the annular seat  33  of the housing  23 .  
         [0027]    A cup-shaped piston  91  having a tubular wall  93  surrounding a cavity  95  is located in the control housing  41  between the piston  77  of the disk valve and the bottom wall  51  of the control housing  41 . The tubular wall has an open end  97  positioned adjacent the valve piston  77  and a base end wall  99  positioned against the bottom wall  51  of the control housing. An annular-shaped seal  101  is located on the outer periphery of the base end wall  99  and engages the tubular wall  49  of the control housing. The tubular wall  93  of the cup-shaped piston is smaller in diameter than its base end wall  99  to provide an annular space  103  between the cup-shaped piston and the tubular wall  49 . Scallops  105  are formed at the open end  97  of the piston to allow water flow into and out of the cavity  95  from the annular space  103 . It should be understood that the tubular wall  93  of the piston  91  could be replaced by a projection such as a post or spacers of other types (not shown) that would engage the piston  77  of the disk valve  71  to define a minimum space between the piston  77  and the annular seal  101  formed on the base wall  99  of piston  91 . It should also be understood that this minimum spacing between the pistons prevents the seals on the pistons from compromising the function of port  67 . However, an advantage of the cup-shaped piston is that it prevents undesirable tilting of the cup-shaped piston in the control housing  41 .  
         [0028]    A conduit  111  connects the port  61  of inlet passage  25  to the port  69  located in the bottom wall  51  of the control housing  41 . Flow in this conduit is controlled by a valve  113  operated by a solenoid  115 . Valve  113  may also include a bleeder (not shown). A conduit  117  connects the port  63  of the outlet passage  27  of the valve housing  23  with the port  67  located in the tubular wall  49  of the control housing  41 . It should be noted that in FIG. 1 the conduit control valve  113  is shown in its closed position. Any pressure in the portion of conduit  111  between valve  113  and port  69  has been bled off. The conduit  117  is unobstructed. The disk valve  71  is moved to its open position by the biasing force of the compression spring  81  while any fluid pressure in the outlet passage  27  is acting through the conduit  117  against the under surface of the piston  77  to provide a balance between the water pressure in the inlet passage  25  and the reduced pressure in the outlet passage  27  thereby regulating the flow of water through the passage  31 .  
         [0029]    [0029]FIG. 2 of the drawings shows the regulator valve  21  of FIG. 1 but in its closed position. Closing of the disk valve  71  against the annular seat  33  of the passage  31  of the valve housing  23  was accomplished by opening valve  113  in the inlet passage conduit  111 . This introduces water under inlet pressure to the underside of the annular seal  101  on the base end wall  99  of the cup-shaped piston  91 . The water under inlet pressure moves the open end  97  of the cup-shaped piston against the piston  77  connected to the stem  75  of the disk valve  71  compressing spring  81  and moving disk valve  71  to its water passage  31  closing position. It should be noted that in the closed position of the valve shown in FIG. 2 the annular seal  101  of the cup-shaped piston  91  separates the pressure introduced into the control housing by the conduit  111  from the port  67  in the tubular wall  49  of the control housing to prevent flow of the pressurized water into the outlet passage  27  of the valve housing. Also, the annular seal  79  of the piston  77  attached to the stem  75  of the disk valve is positioned below the port  65  in the cylindrical wall  49  of the control housing to prevent any leakage through this port which functions in this embodiment of the invention as a vent.  
         [0030]    The regulator valve  21  shown in the embodiment of FIGS. 3 and 4 of the drawings is identical in construction to valve  21  shown in FIGS. 1 and 2 except that the connections of the inlet passage conduit and outlet passage conduit to the ports of the control housing  41  are rearranged. In the modification of FIGS. 3 and 4, an inlet passage conduit  131  connects the port  61  of the inlet passage  25  of the housing  23  to the port  67 , which is the lower port in the cylindrical wall  49  of the control housing. An outlet passage conduit  133  connects the port  63  in the outlet passage  27  of the housing  23  with the port  69  located in the bottom wall  51  of the control housing  41 .  
         [0031]    In FIG. 3 of the drawings, the valve  21  is shown in its normally open or regulating position. The valve  113  in conduit  131  leading from the inlet passage  25  of the valve housing  23  is closed with its automatic bleeder opening functioning to relieve pressure in conduit  131  downstream of the valve  113 . The compression spring  81  has biased the disk valve  71  to its open position. The spring is bearing against the piston  77  which in turn engages the cup-shaped piston  91  in a position above the bottom wall  51  of the control housing  41 . Regulating pressure through the conduit  133  passes through port  69  in the bottom wall  51  of the control housing  41  to act against the underside of cup-shaped piston  91  to hold piston  91  away from bottom wall  51 . The regulating pressure acts against the piston  77  and spring  81  regulating flow through the opening  31  in the partition  29  of the valve housing  23  by resisting opening movement of the disk valve  71  caused by flow through the passage  31 .  
         [0032]    [0032]FIG. 4 of the drawings shows the normally open valve  21  in its closed position. In this condition of the regulating valve, the valve  113  in conduit  131  is in its open position admitting water at inlet passage pressure through port  67  where it acts against the piston  77  to move it to an upright position where spring  81  is compressed and disk valve  71  moves into contact with seat  33  to seal the water opening  31  in partition  29  of valve housing  23 . The pressure from the water being admitting through port  67  separates the cup-shaped piston  91  from the disk-shaped piston  77  and bottoms it in the control housing  41 . The annular seal  101  on the cup-shaped piston  99  prevents inlet passage water from entering the conduit  133  connected to the outlet passage  27  at port  63 .  
         [0033]    A modified regulator valve  151  is depicted in FIGS.  5 - 14  of the drawings. FIGS.  8 - 14  show the identical valve as is shown in FIGS.  5 - 7  but also depicts various modifications of the conduit connections between the inlet and outlet passages and the ports in the control housing. Because essentially the same parts are found in regulator valve  21 , previously described, and in modified regulator valve  151 , similar parts will be identified by the same numbers in the following description except in situations where the construction, relative placement of a part or its function has changed such that clarity in describing the construction, relative location or function of the part will be enhanced by assigning a different number to it.  
         [0034]    FIGS.  5 - 7  of the drawings show a first embodiment of the modified regulator valve  151 . This valve is almost identical to the previously described valve  21  except that a compression spring  153  seats in the cup-shaped piston  91  and engages the piston  77  to bias the disk valve  71  to its closed position shown in FIG. 5 of the drawings. In this embodiment of the modified regulator valve  151 , a conduit  155  connects at one end to the port  61  of the inlet passage  25  and to the port  65  in the cylindrical wall  49  of the control housing  41  at its other end. A conduit  157  connects the port  63  of the outlet passage  27  to the lower port  67  in the cylindrical wall  49  of the control housing  41 . As shown in FIG. 5, the regulator valve  151  is in its closed position with the compression spring  153  extended to engage the piston  77  and force the disk valve  71  into contact with the annular seat  33  of the opening  31  in the valve housing  23 . There is no fluid pressure acting on the piston  77  or the cup-shaped piston  91  because the valve  113  is in its closed position set by the solenoid  15  and there is no pressure in the outlet passage  27  of the valve housing  23 .  
         [0035]    [0035]FIG. 6 of the drawings shows the regulator valve  151  in its fully open position. This is accomplished by the solenoid moving the valve  113  to its open position allowing fluid pressure in inlet passage  25  to flow through the conduit  155  to the port  65  in the cylindrical wall  49  of the control housing  41 . The fluid pressure acts against the piston  77  compressing spring  153  and moving the disk valve  71  to its fully open position allowing fluid flow through the opening  31  in the partition  29  and into the outlet passage  27 . Pressure from the inlet pressure conduit  155  forces the piston  77  against spring  153  to compress it and to seat the cup-shaped piston  91  against the bottom wall  51  of the control housing  41 .  
         [0036]    [0036]FIG. 7 shows the regulator valve  151  in its open regulating condition. This is achieved by closing the valve  113  controlled by the solenoid  115  while the valve  151  is in its fully open position as shown in FIG. 6 of the drawings. With the valve  113  in the inlet passage conduit  155  closed, pressure is automatically bled from the conduit allowing the compressed spring  153  to act on the disk valve piston  77  to move it toward the annular seat  33 . However, the downstream pressure acting through the outlet pressure conduit  157  enters the control housing  41  through the port  67  acting on the underside of the piston  77  and assisting the compression spring  153  to force the disk valve against the inlet pressure of the fluid passing through the annular seat  33  to reach a balanced or equilibrium condition as shown in FIG. 7.  
         [0037]    The regulator valve  151 , shown in the embodiment of FIGS. 8, 9 and  10  of the drawings, is identical in construction to valve  151  shown in FIGS. 5, 6 and  7  except that the connections of the inlet passage conduit and outlet passage conduit to the ports of the control housing  41  are rearranged. In the modification of FIGS. 8, 9 and  10 , an inlet passage conduit  161  connects the port  61  of inlet passage  25  with the port  65  formed in the cylindrical wall  49  of the control housing  41 . An outlet passage conduit  163  connects the port  63  in the outlet passage  27  to the port  69  in the bottom wall  51  of the control housing  41 . FIG. 8 of the drawings shows the control valve in its normally closed position. The valve  113  in the inlet pressure conduit  161  is in its closed position and bleeds pressure from the conduit. The compression spring  153  acting on the piston  77  moves the disk valve  71  into engagement with the annular seat  33  to close the opening  31  between the inlet passage  25  and the outlet passage  27 . Also, as influenced by this spring  153 , the cup-shaped piston  91  is moved into engagement with the bottom wall  51  of the control housing  41 .  
         [0038]    The fully open position of control valve  151  of FIG. 8 is shown in FIG. 9. The disk valve  71  is moved to its fully opened position by opening the valve  113  in the conduit  161  leading from the inlet passage  25  of the valve  23  by actuating the solenoid  115 . The pressure from the inlet passage conduit  161  is directed through port  65  into the control housing  41  where it forces the piston  77  against the spring  153  to compress the spring and move the cup-shaped piston  91  into contact with the bottom wall  51  of the control housing  41 .  
         [0039]    To change the condition of the control valve  151  to its open regulating position shown in FIG. 10 of the drawings, the solenoid  115  is actuated to close the valve  113  in the inlet passage conduit  161 . Closing of the valve  113  allows the bleeding of pressure in conduit  161  permitting the compressed spring  153  to move the piston  77  and the disk valve  71  towards the annular seat  33  around the opening  31  connecting inlet passage  25  and outlet passage  27 . As the valve  71  throttles water flow through the opening  31 , downstream pressure in outlet passage  27  passes through conduit  163  and through port  69  in the bottom wall  51  of the control housing  41  to move the cup-shaped piston  91  upwardly away from end wall  51  and assist spring  153  in biasing disk valve  71  toward its closed position. The throttling effect of the valve  71  produces an equilibrium condition as shown in FIG. 10 of the drawings whereby the outlet pressure in outlet passage  27  is maintained at a desired level.  
         [0040]    The regulator valve shown in FIG. 11 of the drawings is identical to the control valve  151 , previously described, except that the connections of the inlet passage conduit and the outlet passage conduit to the ports of the control housing  41  are rearranged. In the modification of FIG. 11, an inlet passage conduit  171  connects the port  61  of inlet passage  25  to the lower port  67  in the cylindrical wall  49  of the control housing  41 . An outlet passage conduit  173  connects the outlet passage port  63  to the port  69  located in the bottom wall  51  of the control housing  41 .  
         [0041]    Valve  151  is shown in its closed position in FIG. 11 with the disk valve  71  engaging the annular seat  33  to prevent flow from the inlet passage  25  to the outlet passage  27  of the housing  23 . Inlet pressure passes through the inlet passage conduit  171  into the control housing  41  through port  67  and through the annular space  103  to act against piston  77  to force it into contact with the seat  33  because the valve  113  is in the open position as actuated by the solenoid  115 . In this arrangement, the inlet pressure supplements the bias of the compression spring  153  to maintain the disk valve  71  in its closed position. The cup-shaped piston  91  is forced into contact with the bottom wall  51  of the control housing  41  and through its annular seal  101  shuts off any fluid to the outlet passage conduit  173 .  
         [0042]    The regulator valve  151 , shown in FIGS. 12, 13 and  14  of the drawings, is identical in construction to the valve  151  shown in FIGS. 5, 6 and  7  of the drawings except that the connections of the inlet passage conduit and the outlet passage conduit to the ports of the control housing  41  are rearranged. In the modification of FIGS. 12, 13 and  14 , an inlet passage conduit  181  connects the port  61  of the inlet passage  25  of the housing  23  to the port  69  in the bottom wall  51  of the control housing  41 . An outlet passage conduit  183  connects the port  63  in the outlet passage  27  with the lower port  67  in the cylindrical wall  49  of the control housing  41 .  
         [0043]    In FIG. 12 of the drawings, the regulator valve  151  is shown in its closed position in which the disk valve  71  engages the annular seat  33  surrounding the opening  31  between the inlet passage  25  and the outlet passage  27 . The valve  113  is in its normally closed position as controlled by the solenoid  115  and the inlet passage conduit  181  downstream of valve  113  is bled free of fluid. In this condition, the compression spring  153  acts against the piston  77  biasing the disk valve  71  into its seated position. The spring  153  also forces the cup-shaped piston  91  to its position in which it is seated against the bottom wall  51  of the control housing  41 . In this condition, the disk valve  71  is held in its closed position strictly by the spring  153 .  
         [0044]    [0044]FIG. 13 of the drawings shows the valve  151  in a position in which the disk valve  71  is held in its closed position against the annular seat  33  by the spring  153  and by upstream pressure diverted from the inlet passage  25 . The solenoid  115  is actuated to open its valve  113  allowing fluid under pressure from the inlet passage  25  into conduit  181  and through port  69  in the bottom wall  51  of the control housing  41 . The fluid acts on the underside of the cup-shaped piston  91  which is sealed by O-ring  101  to move the cup-shaped piston  91  and the compression spring  153  against the piston  77  holding it in its closed position. The O-ring seal  101  on cup-shaped piston  91  seals off port  67  in the cylindrical wall  49  of the control housing  41  to prevent the escape of fluid through the outlet pressure conduit  183 .  
         [0045]    [0045]FIG. 14 of the drawings shows the valve  151  in its fluid flow regulating position. Valve  113  is closed by its solenoid  115  and pressure is drained from the inlet pressure conduit  181  allowing the compression spring  153  and the cup-shaped piston  91  to move towards the base wall  51  of the control housing  41  due to pressure of inflowing fluid in the inlet passage  25 . As the fluid passes through the annular seat  33 , its pressure is throttled by the valve  71 . The outlet pressure in passage  27  is directed through the outlet passage conduit  183 , through the port  67  and into the control housing  41  to act against the piston  77  in conjunction with the spring  153  thus providing a balanced pressure to the disk  71  to maintain it in a position of equilibrium as shown in FIG. 14 of the drawings.  
         [0046]    The normally closed valves  151  shown in FIGS.  5 - 7  and  12 - 14  can be modified by the inclusion of additional control conduits to provide pressurized closing to the valve of FIGS.  5 - 7  and pressurized opening to the valve of FIGS.  12 - 14 . For example, in the valve  151  of FIGS.  5 - 7 , an additional control conduit similar to conduit  155  could be connected between inlet passage  25  and port  69 . This conduit could be pressurized by opening a valve similar to valve  113  which is actuated by a solenoid similar to solenoid  115 . The pressurized fluid in the additional control conduit would act on the underside of the cup-shaped piston  91  in control housing  41  to move the piston  91  and compression spring  153  against piston  77  to force valve  71  to its closed position.  
         [0047]    The provision of an additional control conduit to valve  151  of FIGS.  12 - 14  will provide a pressure opening capability to this valve. This can be accomplished by connecting a conduit similar to conduit  181  between inlet passage  25  and the port  65 . This conduit can be pressurized by opening a valve similar to valve  113  operated by a solenoid similar to solenoid  115 . The pressurized fluid in the control conduit will introduce fluid under pressure into the control housing  41  to act on the upper surface of piston  77  to compress spring  153  and force the cup-shaped piston  91  to the bottom of the control housing  41  so that the valve  71  is in its fully open position.  
         [0048]    The regulator valve shown in FIG. 15 is identical in construction to the valve  21  shown in FIGS. 1 and 2 except that the piston  77  and the cup-shaped piston  91  shown in the embodiment of FIGS. 1 and 2 are replaced by flexible partitions such as diaphragms which provide fluid tight sealing with the wall of the control chamber  41  to isolate the ports  65 ,  67  and  69  from one another. As a replacement for the piston  71 , a flexible diaphragm  197  is attached to the end of the stem  75  of the valve  71 . A bead  199  formed as the peripheral edge of the diaphragm is anchored in the tubular wall  49  of the control housing  41 . The cup-shaped piston  91  formed in the valve shown in FIGS. 1 and 2 is replaced by a flexible diaphragm  207  and a guide rod mechanism  209 . The rod mechanism  209  functions as a spacer replacing the tubular wall  93  of the previous piston  91  to maintain the minimum spacing between the diaphragms so as to prevent the diaphragm from compromising the functions of port  67  in the control housing wall. The diaphragm  207  also has a bead  211  at its peripheral edge which is anchored in the tubular wall of the control housing  41 .  
         [0049]    An additional control conduit similar to conduit  111  can be connected between inlet passage  25  and port  65  of the valve  21  of FIG. 15 to provide the option of pressurized opening of the valve  71 . This conduit can be pressurized by opening a valve similar to valve  113  operated by a solenoid similar to solenoid  115 . The pressurized fluid in this additional control conduit would introduce fluid under pressure into the control housing  41  to act on the upper surface of the diaphragm  197  to force the diaphragm  197 , the spacer rod assembly  209  and the diaphragm  211  in a direction of the bottom of the control housing  41  to move the valve  71  to its fully opened position.  
         [0050]    While a preferred form of the invention has been shown and described, it will be realized that alterations and modifications may be made thereto without departing from the scope of the following claims. For example, while the conduits are shown connecting to ports in the inlet and outlet passages of the valve housing, these conduits could be connected to points remote from the valve body itself. That is, the conduit could be connected to the main pipeline upstream and downstream of the valve body so long as the pressure flowing into the inlet passage is provided to one conduit and the pressure at the outlet passage is supplied to the other conduit. Furthermore, it will be understood that the extender or spacer shown as cup-shaped member could be otherwise configured to prevent it from tilting in the control housing. The spacer, whether cup-shaped or otherwise could be associated with the rod piston or with the rod itself.