Patent Publication Number: US-2015060708-A1

Title: Bellows valve with valve body cylinder adapter

Description:
RELATED APPLICATION 
     This application claims the benefit of pending U.S. Provisional Application Ser. No. 61/872,077, which was filed on Aug. 30, 2013, for BELLOWS VALVE WITH VALVE BODY CYLINDER ADAPTER, the entire disclosure of which is fully incorporated herein by reference. 
    
    
     BACKGROUND OF THE DISCLOSURE 
     The inventions relate to flow valves. The inventions more particularly relate to valves that utilize sealed subassemblies, for example a bellows. 
     SUMMARY OF THE DISCLOSURE 
     A first inventive concept presented herein provides a valve design that facilitates machining one or more flow passageways in a valve body. In an embodiment, a valve cavity at least partially receives a valve member subassembly and an adapter. Additional embodiments are presented herein. 
     These and other inventive concepts and embodiments are fully described hereinbelow, and will be readily understood by those skilled in the art from the following detailed description of the exemplary embodiments in view of the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an isometric view of an embodiment of a valve in accordance with the teachings herein, in combination with a pneumatic actuator. 
         FIG. 2  is the embodiment of  FIG. 1  in longitudinal cross-section. 
         FIG. 3  is the embodiment of  FIGS. 1 and 2  in exploded isometric. 
         FIG. 4  illustrates an isometric view of another embodiment of a valve in accordance with the teachings herein. 
         FIG. 5  is the embodiment of  FIG. 4  in longitudinal cross-section with the valve in a closed position. 
         FIG. 6  is the embodiment of  FIG. 4  in longitudinal cross-section with the valve in an open position. 
         FIG. 7  is the embodiment of  FIGS. 4-6  in exploded isometric. 
     
    
    
     DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
     The exemplary embodiments described herein are directed to a bellows valve, and to a bellows valve in combination with an actuator assembly, however, many different designs and configurations for the bellows valve and/or the actuator may be used as needed for particular applications. Use of the terms axial and radial are referenced to a longitudinal axis, such as for example, a central longitudinal axis X as noted on the drawings. In the exemplary drawings, the longitudinal axis X may be the central longitudinal axis of the valve body wherein a valve member or bellows or both are coaxial with the axis X. 
     A first inventive concept presented herein provides a valve design that facilitates machining one or more flow passageways in a valve body. In an embodiment, a valve body is formed with a valve cavity that is dimensioned so that angled ports and flow passageways can be machined with reduced difficulty. These dimensions may include diameter and axial length. For example, a larger inside diameter or alternatively a shorter valve body wall, or both, may be used that otherwise could not be realized without the inventive teachings herein. This allows larger flow passageways to be machined at shallower angles thereby providing greater flow through the valve compared to conventional valve bodies that result in steeper angles and smaller flow passageways. 
     In a further embodiment, the valve cavity at least partially receives a valve member subassembly and an adapter. The adapter may have a generally cylinder shape and is received in a generally cylinder shaped portion of the valve cavity. The adapter provides a seal with the valve member subassembly and a seal with the valve body to provide a sealed fluid flow cavity. Additional embodiments of this concept are presented herein. 
     In addition, use of an adapter as taught herein facilitates the ability to use a common or single valve body design with different bellows, for example, bellows having different dimensions (diameter or longitudinal length for example.) 
     Another inventive concept presented herein provides a valve design that facilitates machining one or more flow passageways in a valve body. In an embodiment, the valve body has a valve cavity that at least partially receives a valve member subassembly and an adapter. The adapter permits the valve body to be made shorter along a longitudinal axis compared to a valve body without an adapter so that the valve body can be more easily machined with flow passageways. The adapter provides a seal with the valve member subassembly and a seal with the valve body to provide a sealed fluid flow cavity. Additional embodiments of this concept are presented herein. 
     Another inventive concept presented herein provides a valve design that facilitates machining one or more flow passageways in a valve body. In an embodiment, the valve body has a valve cavity that at least partially receives a valve member subassembly and an adapter. The adapter permits the valve body to be made with a larger internal diameter compared to a valve body without a adapter so that the valve body can be more easily machined with flow passageways. The adapter provides a seal with the valve member subassembly and a seal with the valve body to provide a sealed fluid flow cavity. Additional embodiments of this concept are presented herein. 
     With reference to  FIGS. 1-3 , we illustrate an embodiment of an actuator and valve assembly  10 . The actuator and valve assembly  10  may include a pneumatic actuator  12  that optionally may be axially stacked on top of a valve  14 . The actuator  12  may include, for example, a pneumatically operated actuator assembly  16 . Alternatively, the actuator  12  may be a manual actuator, for example with a handle or lever, or an electromagnetic actuator or a hydraulic actuator or any other type of actuator that produces a linear motion to open and close the valve  14 . 
     The valve  14  may have many different configurations and uses. For the exemplary embodiment illustrated herein, the valve  14  may be realized in the form of a valve that uses a hollow extensible member  18  ( FIG. 2 ), for example a bellows, that extends and contracts axially to move a valve closure element ( 36 ) to open and close the valve  14  in response to operation of the actuator  12 . Although the exemplary embodiments herein are described in the context of a bellows valve, we intend the terms “hollow extensible member” and “bellows” to be construed broadly, and to include a conventional or traditional bellows design or alternative bellows designs, for example a series of conical elements or springs or other elements that form a hollow extensible member. Bellows valves find particular use for high purity, high flow rate applications, but the inventions may be used in valves for many other types of applications. 
     An embodiment of a bellows valve in accordance with the teachings herein includes a valve body  20  that has two or more flow passageways therein so as to control the flow of fluid, for example a liquid or gas, from one port to another. For example, in a two port embodiment, a first or inlet flow port  22  (which is hidden in the orientation of  FIG. 1 ) opens to a first or inlet flow passageway  24 . A second or outlet flow port  26  opens to a second or outlet flow passageway  28 . A sealed fluid flow cavity  30  opens to the outlet flow passageway  28  when the valve  14  is in an open position (note that  FIG. 2  shows a valve closed position). The inlet flow passageway  24  opens to the sealed fluid flow cavity  30 . The designations of inlet and outlet are arbitrary, it being understood that flow can be reversed through the valve  14  if so desired, and flow can be directed to other ports in a multi-port embodiment (not shown) if so need. The fluid flow cavity  30  is sealed in the sense that fluid is contained when the valve  14  is closed and fluid flows between the first flow passageway  24  and the second flow passageway  28  when the valve  14  is open. 
     A valve member subassembly  32  is at least partially disposed in a valve cavity  34  that optionally may be formed in a generally cylindrical shape in the valve body  20 . The valve member subassembly  32  may include a valve closure element  36 , for example, a valve stem. The valve stem  36  optionally carries or supports a valve seat  38 . Alternatively, the valve seat  38  may be disposed in a groove in the valve body  20 . The valve closure element  36  preferably is sealingly attached to a first end  18   a  of the bellows  18 . For example, the valve closure element  36  may be welded to the bellows  18  generally at the location  18   a.    
     The bellows  18  preferably is also sealingly attached to a support ring  40  at a second end  18   b  of the bellows that is axially opposite the first end  18   a  of the bellows. For example, the valve closure element  36  may be welded to the bellows  18  generally at the location  18   b . With the bellows  18  fully welded, the bellows  18  along with the support ring  40  and the valve closure element  36  sealingly encloses an optional biasing member  42 , for example a spring. An upper portion  36   a  of the valve stem  36  is also sealingly enclosed as with the biasing member  42 . The biasing member  42  may be captured between a spring guide or upper bushing  44  and a lower bushing  46 , and held in compression by a threaded member  48  that may be screwed into an upper end of the valve stem  36 . The lower bushing  46  is supported by a radially inward flange  50  on the support ring  40 . The compressed biasing member  42  applies an upward force on the valve stem  36  so that the valve  14  in this embodiment is a normally open valve (disregarding for the moment operation of the actuator  12 .) Many other designs may be used to provide the normally open functionality, and alternatively the valve  14  may be designed as a normally closed valve. Note that the biasing member  42  also causes the bellows  18  to compress longitudinally when the valve closure element  36  is moved upward (as viewed in  FIG. 2 .) 
     The valve body  20  may be machined or otherwise formed with a valve cavity wall  34  (valve cavity  34  for short herein) a portion of which may be cylindrical or may be generally cylindrical in shape, although alternatively other geometries may be used as needed. The valve member subassembly  32  is at least partially received in the valve cavity  34  (in the embodiment of  FIG. 2  the valve member subassembly  32  is fully received in the valve cavity  34  while in the second embodiment of  FIG. 5  that valve member subassembly  96  is partially received in the valve cavity.) An adapter  54  is disposed within the valve cavity  34 . The adapter  54  may be shaped generally as a cylinder to be received in the valve cavity  34 . Alternative geometry shapes may be used, it being preferred for convenience but not required that the adapter  54  generally conform to the shape of the valve cavity  34  (herein the adapter  54  may also be referred to as a cylinder adapter  54  for embodiments having generally cylindrical shapes for the adapter  54  and the valve cavity portion that receives the adapter.) From  FIG. 3  it will be noted the generally cylindrical embodiment for the adapter  54  and the valve cavity  34 . The adapter  54  thus has a smaller inside diameter than the diameter of the valve cavity  34  and a larger diameter than the bellows  18 . 
     A bonnet nut  56  may be joined with the valve body  20  using a threaded connection  58  or other suitable means. The adapter  54  is captured and compressively axially loaded between an upper flange  60  of the support ring  40  and a support surface  62  of the valve body  20  when the bonnet nut  56  is tightened down. A fluid tight body seal  64  is made between a lower surface  54   a  of the cylinder adapter  54  and the support surface  62 , and a fluid tight bellows seal  66  is made between an upper surface  54   b  of the cylinder adapter  54  and a surface  60   a  of the upper flange  60  of the support ring  40 . To facilitate the bellows seal  66  and the body seal  64 , the adapter  54  may include on the upper surface  54   b  an upper annular bead that forms a compression face seal with the surface  60   a  of the upper flange  60 , and the adapter  54  may include on the lower surface  54   a  a lower annular bead that forms a compression face seal with the support surface  62 . Therefore, after the bonnet nut  56  is tightened down onto the valve body  20 , the adapter  54  in combination with the valve body  20  and the support ring  40  subdivides or partitions the valve cavity  34  to provide a sealed fluid flow cavity  68  (when the valve  14  is installed or plumbed with inlet and outlet fittings or connections attached.) The sealed fluid flow cavity  68  provides a fluid tight flow path between the first flow passageway  24  and the second flow passageway  28  when the valve  14  is in an open position and a sealed flow cavity when the valve  14  is in a closed position. 
     The adapter  54  in effect allows for the valve body  20  to be machined with a larger valve cavity  34  than could otherwise be provided if the adapter  54  were not used. As noted above, by larger valve cavity is meant that dimensionally either the diameter of the valve cavity can be made larger for machining the flow passageways or a shallower or shorter longitudinal length, or both if so desired. In the embodiment of  FIGS. 1-3 , the adapter  54  allows for a larger inside diameter of the valve cavity  34  to facilitate machining. In the second embodiment described below, an adapter may be used that provides for an axially or longitudinally shorter valve body to facilitate machining. The improved dimensioning of the valve cavity makes it easier to machine the flow passageways with shallower angles (i.e. less severe angles because deeper or sharper angles and corners in a flow path can reduce flow rate.) This allows more access room to insert a drill tool to form the angled flow passageways  24 ,  28 . Therefore, the flow passageways  24 ,  28  can be formed at shallower angles (meaning the flow path through the valve is more of an in-line flow path) and with larger diameters than can be achieved if the adapter concept is not used. This is especially advantageous for valves that must meet a required space constraint. 
     The lower bushing  46  serves to help center the valve closure element or valve stem  36 . The valve stem  36  may for example be a floating valve stem as depicted in  FIG. 2 , meaning that the valve stem  36  is not tied or mechanically connected to the actuator  12 . Rather, the valve stem  36  upper end simply contacts a drive member ( 76 ) of the actuator ( 12 .) The lower bushing  46  helps maintain alignment and self-centering of the valve stem  36  so as to form an effective closing seal when the valve  14  is in the closed position. 
     The pneumatically operated actuator assembly  16  ( FIG. 2 ) may include a piston assembly  70  that is disposed in an actuator housing  72 . The actuator  12  may be mounted to the valve  14  by a threaded connection  56   a  with the bonnet nut  56 . As shown, the actuator housing  72  may be a multi-piece housing or alternatively a single piece housing. In the exemplary embodiment, two pistons may be used but alternatively a single piston actuator may be used or more than two pistons may be used as needed. A spring  74  biases the piston assembly  70  downward against the force of the biasing member  42 . The piston assembly  70  optionally may drive a drive member  76 , for example in the form of an actuator stem  76  that contacts and upper end of the valve member subassembly  32 , for example, an upper surface of the threaded member  48 . The spring  74  is stronger than the biasing member  42  so that with no air pressure applied to the actuator  12 , the valve  14  is in a closed position and the bellows  18  is longitudinally extended. When pressurized air is supplied to the pneumatically operated actuator assembly  16 , the air pressure moves the piston assembly  70  against the force of the spring  74 , thereby allowing the biasing member  42  to longitudinally compress the bellows  18  to lift the valve closure element  36 , thereby opening the valve  14 . Alternatively, the actuator  12  may be configured so that application of pressurized air to the piston assembly  70  closes the valve  14  to provide a normally open valve. The same functionalities may alternatively be achieved with manual actuators or other actuator designs. 
     With reference to  FIGS. 4-7 , another embodiment of a valve  80  in accordance with the teachings herein is illustrated.  FIGS. 4-7  only show the valve, not the associated actuator. An actuator as in the above embodiment may be used or a different actuator may be used as needed. 
     The valve  80  may have many different configurations and uses. For the exemplary embodiment illustrated herein, the valve  80  may be realized in the form of a valve that uses a hollow extensible member  82  ( FIG. 5 ), for example a bellows, that extends and contracts axially or longitudinally to move a valve closure element ( 100 ) to open and close the valve  80  in response to operation of an actuator. Although the exemplary embodiments herein are described in the context of a bellows valve, we intend the terms “hollow extensible member” and “bellows” to be construed broadly, and to include a conventional or traditional bellows design or alternative bellows designs, for example a series of conical elements or springs or other elements that form a hollow extensible member, or designs that function similarly but are not necessarily understood to be a bellows in the conventional sense. Bellows valves find particular use for high purity, high flow rate applications, but the inventions may be used in valves for many other types of applications. 
     An embodiment of a bellows valve in accordance with the teachings herein includes a valve body  84  that has two or more flow passageways therein so as to control the flow of fluid, for example a liquid or gas, from one port to another. For example, in a two port embodiment, a first or inlet flow port  86  opens to a first or inlet flow passageway  88 . A second or outlet flow port  90  opens to a second or outlet flow passageway  92 . A sealed fluid flow cavity  94  opens to the outlet flow passageway  92  when the valve  80  is in an open position (note that  FIG. 5  shows a valve closed position and  FIG. 6  shows a valve open position). The inlet flow passageway  88  opens to the sealed fluid flow cavity  94 . The designations of inlet and outlet are arbitrary, it being understood that flow can be reversed through the valve  80  if so desired, and flow can be directed to other ports in a multi-port embodiment (not shown) if so need. The fluid flow cavity  94  is sealed in the sense that fluid is contained when the valve  80  is closed and fluid flows between the first flow passageway  88  and the second flow passageway  92  when the valve  80  is open. 
     A valve member subassembly  96  may be at least partially disposed in a valve cavity  98  that optionally may be formed in a generally cylindrical shape in the valve body  84 . The valve member subassembly  96  may include a valve closure element  100 , for example, a valve stem. The valve stem  100  optionally carries or supports a valve seat  102 . Alternatively, the valve seat  102  may be disposed in a groove in the valve body  84 . The valve closure element  100  preferably is sealingly attached to a first end  82   a  of the bellows  82 . For example, the valve closure element  100  may be welded to the bellows  82  generally at the location indicated at  82   a.    
     The bellows  82  preferably is also sealingly attached to a support ring  104  at a second end  82   b  of the bellows that is axially opposite the first end  82   a  of the bellows. For example, the valve closure element  100  may be welded to the bellows  82  generally at the location indicated at  82   b . With the bellows  82  fully welded, the bellows  82  along with the support ring  104  and the valve closure element  100  sealingly encloses an optional biasing member  106 , for example a spring. An upper portion  100   a  of the valve stem  100  is also sealingly enclosed as with the biasing member  106 . The biasing member  106  may be captured between a spring guide or upper bushing  108  and a lower bushing  110 , and held in compression by a retainer  112 , for example a snap ring or other suitable retainer, that is received in a recess  100   b  in the valve stem  100 . The lower bushing  110  is supported by a radially inward flange  114  on the support ring  104 . The compressed biasing member  106  applies an upward force on the valve stem  100  so that the valve  80  in this embodiment is a normally open valve (disregarding for the moment the operation of an actuator.) Many other designs may be used to provide the normally open functionality, and alternatively the valve  80  may be designed as a normally closed valve. Note that the biasing member  106  also causes the bellows  82  to compress longitudinally when the valve closure element  100  is moved upward (see  FIG. 6 .) 
     The valve body  84  may be machined or otherwise formed with the valve cavity wall  98  (valve cavity  98  for short herein) a portion of which may be cylindrical or may be generally cylindrical in shape, although alternatively other geometries may be used as needed. The valve member subassembly  96  is at least partially received in the valve cavity  98  (in the embodiment of  FIG. 2  the valve member subassembly  32  is fully received in the valve cavity  98  while in the second embodiment of  FIG. 5  that valve member subassembly  96  is partially received in the valve cavity  98 .) An adapter  116  is disposed within the valve cavity  98  thereby having a smaller inside diameter than the diameter of the valve cavity  98  and larger than the diameter of the bellows  82 . As in the first embodiment above, the valve cavity  98  may have a cylindrical portion that receives the adapter  116  that may also be in the general shape of a cylinder (as in the first embodiment the adapter  116  may be referred to herein as a cylinder adapter for the described embodiment.) 
     A bonnet nut  118  may be joined with the valve body  84  using a threaded connection  120  or other suitable means. The adapter  116  is captured and compressively axially loaded between an upper flange  122  of the support ring  104  and a support surface  124  of the valve body  84  when the bonnet nut  118  is tightened down. A fluid tight body seal  126  is made between a lower surface  116   a  of the adapter  116  and the support surface  124 , and a fluid tight bellows seal  128  is made between an upper surface  116   b  of the adapter  116  and a surface  122   a  of the upper flange  122  of the support ring  104 . To facilitate the bellows seal  128  and the body seal  126 , the adapter  116  may include on the upper surface  116   b  an upper annular bead that forms a compression face seal with the surface  122   a  of the upper flange  122 , and the adapter  54  may include on the lower surface  116   a  a lower annular bead that forms a compression face seal with the support surface  124 . Therefore, after the bonnet nut  118  is tightened down onto the valve body  84 , the adapter  116  in combination with the valve body  84  and the support ring  104  subdivides or partitions the valve cavity  98  to provide a sealed fluid flow cavity  130  (when the valve  80  is installed or plumbed with inlet and outlet fittings or connections attached.) The sealed fluid flow cavity  130  provides a fluid tight flow path between the first flow passageway  88  and the second flow passageway  92  when the valve  80  is in an open position and a sealed flow cavity when the valve  80  is in a closed position. 
     The adapter  116  in effect allows for the valve body  84  to be machined with a shallower valve cavity  98  than could otherwise be provided if the adapter  116  were not used. The valve body  84  may include an upper wall  84   a  which may be longitudinally shorter than in a traditional valve because the adapter  116  effectively serves as a valve body extension. By longitudinally shorter is meant that the upper wall  84   a  extends or terminates axially from the flow passageways  88 ,  92  by a lesser distance as compared to a traditional valve body.) As viewed in  FIG. 5 , for example, the adapter  116  upper end may extend axially in effect to the length of the valve body wall  84   a  that would be needed to accommodate the length of the bellows  82  if the adapter  116  were not used. In other words, the adapter  116  has a distal upper end that extends axially past a distal upper end of the valve body  84  that joins with an actuator. For example, when installed, the distal end of the adapter  116  is axially further from the flow passageways  88 ,  92  than the distal end of the valve body  84 . This allows the flow passageways  88  and  92  to be machined more easily before the adapter  116  is installed, thereby facilitating the machining operation because the shorter valve body allows the machine tool easier access into the valve cavity. The shorter valve body allows more access room to insert a drill tool to form the angled flow passageways  92 . Thus, for both embodiments of  FIGS. 2 and 5  the separate adapter ( 54 ,  116 ) facilitates valve body machining operations by effectively opening up access into the valve cavity to form the angle flow passageways as previously described hereinabove. 
     As in the first embodiment, the lower bushing  110  serves to help center the valve closure element or valve stem  100 . In both embodiments, a lower bushing and floating valve stem design are optional. Also note that the first and second ports  86 ,  90  in the second embodiment are located in a common lower surface of the valve body  84 . As such, this configuration is what is generally and commonly known as a surface mount configuration. However, other porting configurations may be used, for example as shown in the first embodiment herein. Mounting bolts  132  may be used to attach a surface mount fluid component to an underlying substrate or manifold as is known. 
     Note that an additional benefit of the adapter concept is that the adapter in effect decouples the valve body from the bellows. In other words, the bellows and the adapter preferably are not welded to each other nor to the valve body. The use of a compression seal or other mechanical seal means (mechanical as distinguished from a welded connection) between the adapter and the valve body as well as between the adapter and the valve member subassembly allows for easy installation of the valve member subassembly into the valve body, and also the adapter and the valve member subassembly to be removed easily and replaced if so needed for maintenance or repair. Alternatively, the adapter may be welded at one end to the valve member subassembly to form a single piece component and then installed with a single compression seal for the body seal. In either scenario, different adapters having different dimensions such as diameter or longitudinal length may be used to accommodate different bellows designs while still fitting into a particular or common valve body. This means that a single valve body size may be used with different bellows sizes by use with an appropriately sized adapter. Moreover, a particular bellows design may be used in differently sized valve bodies by providing different adapters as needed. 
     The inventive aspects and concepts have been described with reference to the exemplary embodiments. Modification and alterations will occur to others upon a reading and understanding of this specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.