Abstract:
A valve manifold includes a valve body carrying pairs of laterally spaced piston actuated valves controlled by control modules operative to selectively pressurize and exhaust an outlet port connected to a fluid device and configured in groupings permitting varying valve functionalities.

Description:
RELATED APPLICATION 
       [0001]    This is a continuation of U.S. application Ser. No. 13/425,820 filed on Mar. 21, 2012, which is a continuation of U.S. application Ser. No. 12/131,092 filed on Jun. 1, 2008, now U.S. Pat. No. 8,177,188 granted on May 15, 2012, which is a divisional of U.S. application Ser. No. 10/223,236 filed on Aug. 19, 2002, now U.S. Pat. No. 7,490,625 granted on Feb. 17, 2009, which is a continuation-in-part of U.S. application Ser. No. 09/840,688, filed on Apr. 23, 2001, now U.S. Pat. No. 6,435,010 granted on Aug. 20, 2002. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to valves for controlling fluid flow, and, in particular, a control valve assembly having valves integrated with a valve manifold for compactly controlling fluid coupled devices. 
       BACKGROUND OF THE INVENTION 
       [0003]    Manufacturers of hydraulic, pneumatic, and containment equipment customarily test the fluid integrity of their components to ensure safe operation in the field. Standards are generally prescribed for leakage rates at test pressures and times correlated to the desired component specifications. 
         [0004]    Currently, leak detection systems are an assembly of separate components housed in portable test units. Using a myriad of valves and pneumatic lines a component to be tested is attached to the test unit and independent valves are sequenced to route pressurized fluid, customarily air, to the component, which is then isolated. The leakage rate at the component is then measured and a part accepted or rejected based thereon. The multiple valves and lines may be integrated into a portable test stand for on-site testing. Nonetheless, the pneumatic system is expansive and cumbersome, with each element posing the potential for associated malfunction and leaks. Further, automation of a testing protocol is difficult because of the independent relationship of the components. Where varying test pressures are required for other components, the system must be retrofitted for each such use. 
         [0005]    For example, the leak detection apparatus as disclosed in U.S. Pat. No. 5,898,105 to Owens references a manually operated systems wherein the testing procedures is controlled by plural manual valves and associated conduit occasioning the aforementioned problems and limitations. 
         [0006]    Similarly, the hydrostatic testing apparatus as disclosed in U.S. Pat. No. 3,577,768 to Aprill provides a portable unit comprised of a plurality of independent valves and associated lines for conducting testing on equipment and fluid lines. The valves are manually sequenced for isolating test components from a single pressure source. U.S. Pat. No. 5,440,918 to Oster also discloses a testing apparatus wherein a plurality of conventional valving and measuring components are individually fluidly connected. 
         [0007]    Remotely controlled leak detection systems, such as disclosed in U.S. Pat. No. 5,557,965 to Fiechtner, have been proposed for monitoring underground liquid supplies. Such systems, however, also rely on an assembly of separate lines and valves. A similar system is disclosed in U.S. Pat. Nos. 5,046,519 to Stenstrom et al. 5,072,621 to Hasselmann. 
         [0008]    U.S. Pat. No. 5,540,083 to Sato et al. discloses remotely controlled electromagnetically operated valves for measuring leakage in vessels and parts. Separate valve and hydraulic lines are required. 
         [0009]    In an effort to overcome the foregoing limitations, it would be desirable to provide a portable leakage detection system for testing the fluid integrity of fluid systems and components that include integrated valving and porting within a compact envelope for automatically controlling a variable testing protocol. The leak detector includes a valve block having internal porting selectively controlled by four identical and unique pneumatic poppet valves for pressurizing the test part, isolating the test part for determining leakage rates with pressure and flow sensors communicating with the porting, and exhausting the test line upon completion of the leakage test. The poppet valves engage valve seats incorporated within the porting. The poppet valves are actuated by pilot valve pressure acting on a pilot piston to effect closure of the valve. The sensors interface with a microprocessor for comparing measurements with the test protocol and indicate pass or fail performance. Upon removal of the pilot valve pressure, the resident pressure in the porting shifts the valve to the open position. The leak detector includes plural inlets for accommodating variable pressure protocols. The leak detector thus eliminates the need for external fluid connections and conduits between the various detector components, eliminates the need for two-way valving actuation, and provides for connection with external test units with a single, easy to install, pneumatic line. 
         [0010]    In another aspect of the invention, the poppet valves may be disposed in sets in a valve manifold to simulate conventional valve functionalities with a plurality of fluidic devices. For three way valve functionality, a pair of the pitot valves operates in controlled phased opposition to apply and vent pressure to a one way actuator. For four way valve functionality, a second set of oppositely configured valve are used for conventional operation of dual controlled devices such as two way actuators. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The above and other objects and advantages of the present invention will become apparent upon reading the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0012]      FIG. 1  is a perspective view of a leak detection valve assembly and control module in accordance with an embodiment of the invention; 
           [0013]      FIG. 2  is a schematic drawing of a leak detection system incorporating the valve assembly of  FIG. 1 ; 
           [0014]      FIG. 3  is a top view of the valve assembly; 
           [0015]      FIG. 4  is a front view of the valve assembly; 
           [0016]      FIG. 5  is a vertical cross sectional view taken along line  5 - 5  in  FIG. 3 ; 
           [0017]      FIG. 6  is a vertical cross sectional view taken along line  6 - 6  in  FIG. 4 ; 
           [0018]      FIG. 7  is a horizontal cross sectional view taken along line  7 - 7  in  FIG. 4 ; 
           [0019]      FIG. 8  is a horizontal cross sectional view taken along line  8 - 8  in  FIG. 4 ; 
           [0020]      FIG. 9  is a fragmentary cross sectional view of a unique poppet valve assembly; 
           [0021]      FIG. 10  is a schematic diagram of the leak detection system; 
           [0022]      FIG. 11  is a truth table for the leak detection system; 
           [0023]      FIG. 12  is a schematic diagram for the control system for the leak detection system; 
           [0024]      FIG. 13  is a perspective view of another embodiment of a valve assembly for a leak detection system; 
           [0025]      FIG. 14  is a perspective view of a valve manifold assembly in accordance with another embodiment of the invention; 
           [0026]      FIG. 15  is a top view of the valve manifold assembly shown in  FIG. 14 ; 
           [0027]      FIG. 16  is a front view of the valve manifold assembly shown in  FIG. 14 ; 
           [0028]      FIG. 17  is a left end view of the valve manifold assembly shown in  FIG. 14 ; 
           [0029]      FIG. 18  is a cross sectional view of the valve manifold assembly shown in  FIG. 14 , with the control module removed and including cross sectional view of valve sets taken along lines A-A and B-B in  FIG. 16  and a schematic view of the control system for the valve sets for three way and four way valve functionality; 
           [0030]      FIG. 19  is a fragmentary cross sectional view taken along line  19 - 19  in  FIG. 18 ; and 
           [0031]      FIG. 20  is a cross sectional view of a valve manifold according another embodiment of the invention illustrating a two way valve functionality. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0032]    Referring to the drawings for the purpose of describing the preferred embodiment and not for limiting same,  FIGS. 1 and 2  illustrate a leak detection system  10  for determining the pressure integrity of components when subjected to pressure conditions during a test period. The leak detection system  10  comprises a valve assembly  12  and a control module  14  operatively coupled with a flow sensor  16  and pressure sensor  18 . As hereinafter described in detail, the leak detector  10  is operative for testing the fluid integrity of test parts to determine is leakage standards are being achieved. 
         [0033]    Referring additionally to  FIG. 10 , the valve assembly  12  is fluidly connected with a low pressure source  20  along line  22 , a high pressure source  24  along line  26 , a test unit  28  for testing such parts along line  30 , and an exhaust  32  along line  34 . Supplemental valves may be disposed in the lines for controlling flow therethrough. 
         [0034]    The control module  14  comprises a pilot valve assembly  36  including pilot valves  40 ,  42 ,  44 , and  46  fluidly connected with a high pressure valve unit  50 , a low pressure valve unit  52 , an exhaust valve unit  54  and an isolation valve unit  56  along lines  60 ,  62 ,  64  and  66 , respectively. The pressure sensor  18  is coupled with the isolation valve unit  56  by line  68 . The flow sensor  16  is connected with the valve units at manifold line  70  and with test part line  30  along line  72 . The pilot valves are connected to pilot pressure  74  by manifold line  76 . The lines and attendant fittings will vary in accordance with the parts undergoing testing and the test conditions. 
         [0035]    Referring to  FIGS. 3 through 8 , the valve assembly  12  comprises a valve block  40  housing via ports to be described below a low pressure valve unit  80 , a high pressure valve unit  82 , an exhaust valve unit  84  and an isolation valve unit  86 . 
         [0036]    As shown in  FIGS. 5 and 8 , the low pressure valve unit  80  is fluidly connected with line  28  and low pressure source  20  by a low pressure inlet port  90  intersecting with a vertical cross port  92 . The high pressure valve unit  82  is fluidly connected with line  26  and high pressure source  24  by a high pressure inlet port  94  intersecting with a vertical cross port  96 . As shown in  FIG. 6 , the isolation valve unit  86  is fluidly connected with the line  30  by the isolation port  98  and vertical port  99 . The exhaust valve unit  84  is fluidly connected with line  32  by exhaust port  100 . As shown in  FIG. 4 , the ports  90 ,  94  and  100  are disposed on the front face  102  of the valve block  12 . The isolation port  98  is disposed on the rear face  104  of the valve block  12 . The ports  100  and  98  are located laterally in a central vertical plane. The ports  90  and  94  are symmetrically disposed on opposite sides of the exhaust port  100  and therebelow. The ports  100 ,  94  and  90  lie in a common horizontal plane. Each of the ports is provided with an outer threaded bore for connection to the associated lines with an appropriate fitting for the fluid application. 
         [0037]    All of the valve units have a common architecture as representatively shown in  FIG. 9 . Therein, a valve unit  110  including a poppet  112  having a valve stem  113  supported by sealing disk  114  for reciprocation between a raised vent position as illustrated and a lowered sealed position in counterbore  115 . The poppet  112  includes a cylindrical valve body  116  carrying 0-ring  117  that engages the annular valve seat  118  of counterbore  115  formed coaxially with a vertical port  120 . The outer rim of the sealing disk  114  is supported at the base of a secondary counterbore vertically above bore  115 . The secondary counterbore outwardly terminates at an internally threaded end. A vent cap  124  includes a cylindrical sleeve  125  threadedly received in the threaded bore and a circular base  126  having a threaded center hole  128 . An actuating piston  129  including 0-ring  130  is axially slidably carried at the interior surface of the sleeve of the vent cap  124  for movement between a raised position engaging the base  128  and a lowered position engaging the top of the valve stem  113  for moving the poppet  112  to the sealed condition. Angularly disposed vent holes  131  are formed in the sleeve  125  for venting the piston. An air line connected with the pilot pressure line is connected at the center hole  128  for connection with the pilot pressure control system. 
         [0038]    In typical operation, when pilot pressure is applied in the chamber above the piston  129 , the piston  129  is forced downwardly thereby shifting the poppet  112  to the sealed position. When the pilot pressure is removed and the port  120  is pressurized, the poppet  112  and the piston  129  are driven to the raised, open position. Assist springs may be deployed, particularly in the isolation valve, for providing additional biasing to the open condition. 
         [0039]    As shown in  FIGS. 5 through 8 , with respect to the exhaust port  100  and valve unit  84 , a counterbore  138  is formed in the bottom surface of the valve block  40  coaxially therewith. A circular sealing blank  140  is retained at a step in the counterbore  138  by a split retaining ring  142  retained in a corresponding annular groove thus defining a pressure chamber  144 . A C-shaped distribution channel or port  150  extends from the chamber  144  upwardly and intersects the counterbores  115  of valve units  110 . 
         [0040]    Accordingly, when either of the pressure valve units is pressurized from its source and the pilot control to the piston is interrupted, the air flow in the ports  92 ,  96 ,  99  shifts the poppets to raised, open positions, thereby pressurizing the distribution port  150  and chamber  144  resulting in pressure communication therebetween. Referring to  FIGS. 3 ,  7  and  8 , a pair of vertical ports  160  communicate upstream of the isolation valve unit  84  for connecting one line of the flow sensor  16  and the pressure sensor  18 . A pair of vertical ports  162  communicates on the other side of the isolation valve units  84  with the distribution port  150 . Accordingly, the flow sensor  16  in a conventional manner measures pressure transients on the part under leakage test while the pressure sensor  18  measures pressure conditions on both sides of the isolation valve. 
         [0041]    The valve unit is operationally connected to an independent test unit whereat parts to be leak tested may be deployed. The test protocol may specify a high pressure test for a defined test period or a low pressure test for a defined test period. Test parts are deemed successful if the leakage under pressure as determined by the flow sensor  16  is below a predetermined threshold. The control system  14  is effective for establishing the appropriate protocol. 
         [0042]    Referring to  FIG. 12 , the control system  14  comprises the pilot valve system  250 , a microprocessor  254  coupled with a control panel  255  for defining and conducting the test protocol, test result indicator lights  256  a display screen  257 , for denoting passing or failing of the test connected to a suitable power supply  258 . The microprocessor  254  contains the protocols for the various parts, preferably programmed through an external computer port  260 . The desired protocol is accessed at control panel  255  through menu button  264 , start button  266  and scroll buttons  268 . 
         [0043]    The operation of the leak detector is illustrated in the truth table of  FIG. 11  and taken in conjunction with the schematic of  FIG. 2 . 
         [0044]    A part to be tested in mounted in the test fixture, the control system initialized and the test protocol selected. Thereafter, the test is initiated by actuating the start button  266 . As a first condition, the high and low pressure lines are pressurized with the accompanying pilot valves  40 ,  42  in the normally open positions with the solenoids deenergized. This applies pilot pressure to the associated poppets to close and seal the high pressure and low pressure valve units  50 ,  52 . Correspondingly, the normally closed exhaust pilot is deenergized and the exhaust valve  54  is in the open position. The normally closed isolation pilot is deenergized and the isolation valve unit  56  is in the open position. 
         [0045]    Thereafter the high pressure pilot  40  is energized, venting the high pressure poppet whereby inlet high pressure air raises the high pressure valve unit  50  to the open position. Concurrently, the exhaust solenoid is energized admitting pilot pressure to the exhaust poppet piston chamber and shifting the exhaust valve unit  54  to the closed position and air flowing past the high pressure poppet pressurizes the exhaust chamber  144  through the distribution channel and past the isolation valve unit  56  to pressurize the test part with high pressure air. Thereafter, the isolation pilot is energized applying pilot pressure to the isolation piston chamber and closing the isolation poppet. Thereafter, the flow sensor  16  monitors pressure transients and through the microprocessor interface denotes pass or fail conditions at the indicator lights. 
         [0046]    Upon completion of the test, the isolation pilot solenoid is deenergized pressurizing the high pressure piston and sealing the high pressure valve seat, thereby ceasing inlet flow. Concurrently, the isolation and exhaust pilot solenoids are deenergized allowing exhaust chamber and part pressure to shift the exhaust and isolation valves to the open position for completion of the test. In the event of excessive pressure lost at the test part, a light biasing spring may be provided at the isolation poppet to ensure movement to the open position. 
         [0047]    For testing under low pressure conditions, the exhaust poppet is closed and the low pressure valving sequenced in similar fashion to the high pressure test detailed above. More particularly, a part to be tested in mounted in the test fixture, the control system initialized and the test protocol selected. Thereafter, the test is initiated by actuating the start button  266 . As a first condition, the high and low pressure lines are pressurized with the accompanying pilot valves in the normally open positions with the solenoids deenergized. This applies pilot pressure to the associated poppets to close and seal the later. Correspondingly, the normally closed exhaust pilot is deenergized and the exhaust poppet is in the open position. The normally closed isolation pilot is denergized and the isolation poppet is in the open position. 
         [0048]    Thereafter the low pressure pilot  42  is energized, venting the low pressure valve whereby inlet low pressure air raises the low pressure valve unit  52  to the open position. Concurrently, the exhaust pilot is energized admitting pilot pressure to the exhaust poppet piston chamber and shifting the exhaust valve unit  54  to the closed position and air flowing past the low pressure poppet pressurizes the exhaust chamber through the distribution channel  150  and past the isolation poppet to pressurize the test part with high pressure air. Thereafter, the isolation pilot solenoid is energized applying pilot pressure to the isolation piston chamber and closing the isolation poppet. Thereafter, the flow sensor monitors pressure transients and through the microprocessor interface denotes pass or fail conditions at the indicator. Upon completion of the test, the isolation pilot is deenergized pressurizing the low pressure piston and sealing the low pressure valve seat, thereby ceasing inlet flow. Concurrently, the isolation and exhaust pilot solenoids are deenergized allow exhaust chamber and part pressure to shift the exhaust and isolation poppets to the open position for completion of the test. 
         [0049]    Referring to  FIG. 13 , a fully integrated package is illustrated for a leak detection valve  280  as described above. The valve  280  comprises an extruded metallic valve body  282  having four valve assemblies  284 , as described above. The valve assemblies are controlled by solenoids  286  carried on a top horizontal surface. The valve body  280  has an isolation port  288  in the illustrated rear wall thereof, and high and low pressure ports, and an exhaust port in the front wall thereof, which are not shown and function as above described. The control lines for the valve assemblies  284  are routed through a distribution bracket  290 . The interior pressure sensors are coupled at pin connector  292  on the top surface of the valve body  280  for operative connection to associated instrumentation. 
         [0050]    Referring to  FIGS. 14 through 17 , in another embodiment of the invention the valving is incorporated into a control valve manifold  300 . The manifold  300  includes an extruded lower valve body  302  carrying on a top surface a plurality of longitudinally spaced control modules  304  for operatively controlling conventional fluidic devices, not shown, coupled at a longitudinal series of associated outlet ports  306  exiting at a longitudinal side wall of the valve body. An inlet port  310  and an exhaust port  312  extend longitudinally through the valve body  302  in parallel spaced relationship for interconnection with the valving as described in greater detail below. 
         [0051]    The ports  310  and  312  terminate at internally threaded ends. At the remote end, the ports are suitably sealed with a stop member, such as a threaded plug (not shown), or coupled with a succeeding manifold. The inlet port  310  is coupled with a supply line for supplying inlet fluid under pressure for control by the valving and controlled operation of the associated fluidic devices. The exhaust port  312  is coupled with an exhaust line for routing to an appropriate location the exhaust fluid. 
         [0052]    A pair of upwardly opening laterally spaced longitudinal channels  320  are formed in the top surface of the valve body  302 . Solenoids  322  are carried in the channels  320  and operatively associated with the control modules  304  for controlling pilot pressure to the valving at pilot lines  324 . The modules  304  are connected to a suitable power source via multiple-pin socket connector  326  carried on the front lateral side wall of the valve body  302 . The valve modules  304  control the flow between the ports  310 ,  312  and the operative outlet ports  306  of the manifold  300 . If certain of the ports are not required for an application, the outlet ports may be plugged or capped, and additionally the associated control module deleted. Any ports associated with the inactive outlet ports are also deleted or plugged. 
         [0053]    It will also be apparent that the length of the valve body may be tailored to the devices to be controlled and may be coupled in series or parallel with other valving manifolds. 
         [0054]    The manifold in controlled formats may be advantageously employed to replicate the functionality of various conventional valving configurations, such as two-way, three-way, four-way, five-way valves. In such configurations, the manifold operates with lower control pressures within a substantially smaller envelope. 
         [0055]    More particularly, as shown in  FIG. 1-8 , each control module  304  is associated with a pair of laterally spaced valves  340 ,  342  in Valve A and valves  344  and  346  in Valve B. The valves are operatively disposed in the valve body  302  as referenced in  FIG. 9  above. 
         [0056]    The inlet valves  340 ,  344  are disposed in upwardly opening vertical bores in the valve body normal to the inlet port  310 . Each valve includes a slidably stem supported inlet valve member  360  downwardly moveable by a floating piston  362  from a raised position communicating with the inlet port  310  and a closed position engaging an annular valve seat downstream of the inlet port. 
         [0057]    The exhaust valves  342 ,  346  are disposed in upwardly opening vertical bodes in the valve body normal to the exhaust port  312 . Each valve includes a slidably stem supported outlet valve member  370  downwardly moveable by a floating piston  372  from a lowered position engaging an annular valve seat upstream of the exhaust port  312  and a raised position communicating with the exhaust port. 
         [0058]    An exhaust plenum chamber  380  is formed in the valve body  302  below the exhaust valve seat and in the open position communicates with the exhaust port. The exhaust plenum chamber  380  is sealed by a circular cover member  382  and sealed as described with reference to the prior embodiment. Referring to  FIG. 19 , a cross passage  384  is formed at the outer periphery of the exhaust plenum chamber and established a fluid path extending serially from the outlet port  306  to the cross passage to the exhaust plenum chamber  380  to the exhaust port. 
         [0059]    Each piston is carried in a valve cap threadedly connected in a bore extending from the top surface of the valve body coaxial with the exhaust valve seat. The valve caps are fluidly connected with branch pilot lines  323  above the piston. 
         [0060]    Referring to Valve A in  FIG. 18  illustrating a three way valve functionality, the exhaust valve  370  is connected at the branch pilot line with a normally open solenoid valve  400  connected with the main pilot line  402 . The inlet valve  360  is connected at the branch pilot line with a normally closed solenoid valve  404  connected with the main pilot line. 
         [0061]    The outlet port  306  is formed in the side of the valve body  302  and intersects the inlet valve bore above the inlet valve seat. The device port is fluidly connected by line to one side of a single acting actuator  410 , including return spring biased piston  411 , by lines  412  and  414 . 
         [0062]    In operation, the inlet valve member  360  is moved upwardly to an open position by inlet pressure on the lower surface thereby shifting the piston to a raised position, establishing a fluid path through outlet port  306  and lines  412 ,  414  and extending actuator piston  411 . The outlet valve member is shifted by the piston to the closed position sealing flow to the outlet port. To retract the piston, the solenoid valves are reversed, whereby the inlet valve member  360  is closed, the outlet pilot pressure removed allowing pressure conditions in the plenum  380  to move the exhaust valve member  370  to the open position and venting the actuator to the exhaust port  312  thereby retracting the actuator piston under the spring biasing. 
         [0063]    For four way simulation according to the invention, Valve B is operatively coupled with Valve A. Valve B has a normally open inlet solenoid valve  420  and a normally closed exhaust solenoid valve  422 . Valve A is coupled with one end of a double acting actuator  430 , including piston  431 , by lines  412 ,  432 . Valve B is couple at the outlet port with the other end of the actuator  430  by line  434 . 
         [0064]    In operation, the extension of actuator is controlled by Valve A as above described, and Valve B is in the exhaust mode. To retract the actuator piston  431 , Valve A is conditioned for exhaust and Valve B is conditioned for pressure, thereby shifting the piston  431  to the retracted position. 
         [0065]    Referring to  FIG. 20 , the valve manifold of the present invention may also provide two way valve functionality. Therein, a valve  500  includes a valve body  502  carrying a valve assembly  504  as described above. The inlet valve member  506  is moved by piston  508  under pilot conditions controlled by normally open solenoid valve  510  between a lower closed position engaging the inlet valve seat and the illustrated raised open position. In the open position with the solenoid valve vented, the valve permits fluid flow from supply line  520  to inlet port  522  past valve member  506  to outlet port  524  to a pressure dependent device  526 . Upon reversal of the solenoid valve  510 , the pilot pressure is applied to the piston to closed the valve member and block flow therethrough. At the next actuation, the inlet pressure shifts the valve member to the open condition. 
         [0066]    With the above constructions, it will be appreciated that the individual valve members may be independently controlled and sequenced to a desired actuation schedule. In particular for spool valve simulation, the normal crossover time between valve positions may be eliminated by concurrent actuation of the solenoids. Should staged actuation be desired, time sequencing may be used. Further the valve ports may be integrated with other flow control. Each such simulation provides the compact size afforded by the valves directly place in the manifold bodies, and the low pilot pressures required by the valves, as well as the valve opening pressures afforded by resident pressurization. 
         [0067]    Having thus described a presently preferred embodiment of the present invention, it will now be appreciated that the objects of the invention have been fully achieved, and it will be understood by those skilled in the art that many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the sprit and scope of the present invention. The disclosures and description herein are intended to be illustrative and are not in any sense limiting of the invention, which is defined solely in accordance with the following claims.