Patent Publication Number: US-11035481-B2

Title: Bi-directional valve device for selective control of fluid flow through multiple converging paths

Description:
RELATED APPLICATIONS 
     This application is a continuation of application Ser. No. 15/174,220, filed on Jun. 6, 2016, which is a continuation of application Ser. No. 14/210,821, now U.S. Pat. No. 9,360,124, which was filed on Mar. 14, 2014 and which claims the benefit of provisional application No. 61/786,760, which was filed on Mar. 15, 2013. Each of these related applications is hereby incorporated into this disclosure by this reference. 
    
    
     FIELD 
     The disclosure relates generally to the field of valve devices for regulating the flow of fluid through fluid paths. The valve devices described in the disclosure are particularly well-suited for use in hand-operated devices, such as medical devices and medical device handles. Specifically described embodiments relate to medical devices for selective suction and irrigation of body passageways. 
     BACKGROUND 
     Various clinical procedures require or benefit from the provision of irrigation and suction to a point of treatment. Irrigation allows the clinician to maintain a wet environment for the surrounding tissue while suction provides a tool for removing debris, excess irrigant or other undesirable material from the point of treatment. 
     Unfortunately, the use of irrigation and suction currently requires the use of separate devices. Thus, in sinus surgery, for example, each time irrigation is desired, the clinician must select a designated irrigation device and advance the device into the nose of the patient before irrigation can be performed. When suction is needed, the irrigation device must be removed from the patient&#39;s nose and laid aside. The clinician must then select a designated suction device and advance the device into the nose of the patient before suction can be applied. As a result, many time-consuming device exchanges must be performed, each of which adds time to the procedure and increases the risk for trauma to the patient as additional entries are required. 
     Thus, a need exists for improved valve devices that allow selective control of multiple fluid paths. 
     BRIEF SUMMARY OF DESCRIBED EMBODIMENTS 
     Various example valve devices are described and illustrated herein. 
     An example valve device comprises a housing defining first and second inlet paths, an outlet path, and a junction in fluid communication with the first and second inlet paths and the outlet path, the housing further defining first and second plunger cavities; a first plunger disposed in the first plunger cavity, the first plunger adapted to move between a first position in which the first plunger impedes fluid flow through the first inlet passage and a second position; a second plunger disposed in the second plunger cavity, the second plunger adapted to move between a first position in which the second plunger impedes fluid flow through the second inlet passage and a second position; and a control member slidably attached to the housing and defining first and second plunger recesses, the first plunger recess sized and configured to receive a portion of the first plunger when the first plunger is in its second position and the second plunger recess sized and configured to receive a portion of the second plunger when the second plunger is in its second position. The control member is movable between a first, proximal position in which the first plunger is in its first position and the second plunger is in its second position and a second, distal position in which the first plunger is in its second position and the second plunger is in its first position. 
     Another example valve device comprises a housing defining a main body defining an internal chamber and an opening providing access to the internal chamber, and a cradle portion defining first and second inlet paths, an outlet path, a junction in fluid communication with the first and second inlet paths and the outlet path, and first and second plunger cavities; a first plunger disposed in the first plunger cavity, the first plunger adapted to move between a first position in which the first plunger impedes fluid flow through the first inlet passage and a second position; a second plunger disposed in the second plunger cavity, the second plunger adapted to move between a first position in which the second plunger impedes fluid flow through the second inlet passage and a second position; and a control member slidably attached to the housing and defining first and second plunger recesses, the first plunger recess sized and configured to receive a portion of the first plunger when the first plunger is in its second position and the second plunger recess sized and configured to receive a portion of the second plunger when the second plunger is in its second position. The control member is movable between a first, proximal position in which the first plunger is in its first position and the second plunger is in its second position and a second, distal position in which the first plunger is in its second position and the second plunger is in its first position. 
     Another example valve device comprises a housing defining a main body defining an internal chamber and an opening providing access to the internal chamber, and a cradle portion defining first and second inlet paths, an outlet path, a junction in fluid communication with the first and second inlet paths and the outlet path, first and second plunger cavities, and first and second rails disposed outside of the internal chamber; a first plunger disposed in the first plunger cavity, the first plunger adapted to move between a first position in which the first plunger impedes fluid flow through the first inlet passage and a second position; a second plunger disposed in the second plunger cavity, the second plunger adapted to move between a first position in which the second plunger impedes fluid flow through the second inlet passage and a second position; and a control member slidably attached to the housing and defining a first channel that receives the first rail, a second channel that receives the second rail, and first and second plunger recesses, the first plunger recess sized and configured to receive a portion of the first plunger when the first plunger is in its second position and the second plunger recess sized and configured to receive a portion of the second plunger when the second plunger is in its second position. The control member is movable between a first, proximal position in which the first plunger is in its first position and the second plunger is in its second position and a second, distal position in which the first plunger is in its second position and the second plunger is in its first position 
     Additional understanding of the inventive valve devices can be obtained with review of the detailed description, below, and the appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a first example valve device having a control member in a first, proximal position. 
         FIG. 1A  is a sectional view of the valve device illustrated in  FIG. 1 , taken along line  1 A- 1 A. 
         FIG. 1B  is a sectional view of the valve device illustrated in  FIG. 1 , taken along line  1 B- 1 B. 
         FIG. 2  is another perspective view of a first example valve device. In this figure, the control member is in a second, distal position. 
         FIG. 2A  is a sectional view of the valve device illustrated in  FIG. 2 , taken along line  2 A- 2 A. 
         FIG. 2B  is a sectional view of the valve device illustrated in  FIG. 2 , taken along line  2 B- 2 B. 
         FIG. 3  is a perspective view of a control member isolated from a first example valve device. 
         FIG. 4  is a top view of the control member illustrated in  FIG. 3 . 
         FIG. 4A  is a top view of an alternative control member. 
         FIG. 5  is a top view of another alternative control member. 
         FIG. 6A  is a sectional view of a second example valve device. In this figure, the control member is in a first, proximal position. 
         FIG. 6B  is a sectional view of the second example valve device. In this figure, the control member is in a second, intermediate position. 
         FIG. 6C  is a sectional view of the second example valve device. In this figure, the control member is in a third, distal position. 
         FIG. 7  is a sectional view of another example control member. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS 
     The following detailed description and the appended drawings describe and illustrate various example valve devices. The description and drawings are exemplary in nature and are provided to enable one skilled in the art to make and use one or more example valve devices. They are not intended to limit the scope of the claims in any manner. 
       FIGS. 1, 1A, 1B, 2, 2A and 2B  illustrate a first example valve device  10 . Valve device  10  includes a housing  12 , first  14  and second  16  inlet paths, outlet path  18 , and junction  20  joining the first  14  and second  16  inlet paths and the outlet path  18 . A first plunger  22  is partially disposed in the first inlet path  14  and is movable between first and second positions. Similarly, a second plunger  24  is partially disposed in the second inlet path  16  and is movable between first and second positions. A control member  26  is slidably disposed on the housing  12  and is movable between a first, proximal position, illustrated in  FIGS. 1, 1A and 1B , and a second, distal position, illustrated in  FIGS. 2, 2A and 2B . In the illustrated embodiment, first  28  and second  30  tubular members are partially disposed in the first  14  and second  16  inlet paths, respectively. Also, an outlet tubular member  32  is partially disposed in the outlet path  18 . 
     Each of the plungers  22 ,  24  provides a barrier to fluid flow through the respective inlet path  14 ,  16  when in its first position, but provides no barrier or less of a barrier to fluid flow through the respective inlet path  14 ,  16  when in its second position. As best illustrated in  FIG. 1A , the control member  26  maintains the first plunger  22  in its first position and provides a barrier that prevents the first plunger  22  from moving to its second position when the control member  26  is in the first, proximal position. Also while in the first, proximal position, the control member  26  receives a portion of the second plunger  24 , allowing it to be positioned in its second position. In contrast, and as best illustrated in  FIG. 2A , the control member  26  maintains the second plunger  24  in its first position and provides a barrier that prevents the second plunger  24  from moving to its second position when the control member  26  is in the second, distal position. Also while in the second, distal position, the control member  26  receives a portion of the first plunger  22 , allowing it to be positioned in its second position. Each plunger in a valve device according to a particular embodiment can have any suitable structure and configuration; the illustrated structures are examples of suitable structures. Another example of a suitable structure is a plunger that defines an aperture through its thickness. With these plungers, the aperture defines a passageway through the plunger that is in communication with the inlet path with which the plunger is associated when the plunger is in its second position, thereby allowing fluid flow through the inlet path and the aperture. When in the plunger is in its first position, however, the aperture is out of alignment with the inlet path and provides a barrier to fluid flow through the inlet path. 
     Movement of the control member  26  between its first, proximal and second, distal positions results in movement of each of the plungers  22 ,  24  between its first and second positions, but in opposite orders. Thus, movement of the control member  26  between its first, proximal and second, distal positions controls fluid flow through the inlet paths  14 ,  16  and into the junction  20  and outlet path  18 . For example, movement of the control member  26  from the first, proximal position, best illustrated in  FIG. 1 , to the second, distal position, best illustrated in  FIG. 2 , forces the first plunger  22  to move from its first position, in which it blocks fluid flow through inlet path  14  as best illustrated in  FIG. 1A , to its second position, in which it provides no barrier or less of a barrier to fluid flow through inlet path  14  as best illustrated in  FIG. 2A . In contrast, movement of the control member  26  from the second, distal position, best illustrated in  FIG. 2 , to the first, proximal position, best illustrated in  FIG. 1 , forces the second plunger  24  to move from its first position, in which it blocks fluid flow through inlet path  16  as best illustrated in  FIG. 2A , to its second position, in which it provides no barrier or less of a barrier to fluid flow through inlet path  16  as best illustrated in  FIG. 1A . As such, movement of the control member  26  between its first, proximal and second, distal positions provides selective control over fluid flow through the inlet paths  14 ,  16  and into the junction  20  and outlet path. 
     In the illustrated embodiment, housing  12  defines an internal chamber  40  within which the first  28  and second  30  inlet tubular members and the outlet tubular member  32  are partially inserted. In this embodiment, each of the first  28  and second  30  inlet tubular members recoils in response to being compressed by the respective plunger  22 ,  24  following the appropriate movement of the control member  26 , as described above. As such, housing  12  defines first  42  and second  44  openings that provide fluid communication to the first  14  and second  16  inlet paths, respectively. Also, housing  12  defines a third opening  46  that provides fluid communication to the outlet path  18 . It is noted that internal chamber can have any suitable size, shape and configuration, and the illustrated chamber is exemplary in nature. Also, the internal chamber is considered optional. For example, a solid form housing can be used, essentially eliminating the internal chamber. 
     Also in the illustrated embodiment, housing  12  defines cradle portion  48  that defines the first  14  and second  16  inlet paths, the junction  20  and the outlet path  18 . Cradle portion  48  also defines first  50 , second  52  and third  54  wall portions that cooperatively define first  56  and second  58  plunger cavities. As best illustrated in  FIGS. 1A and 2A , first  50  and second  52  wall portions cooperatively define first plunger cavity  56 , within which the first plunger  22  is disposed and able to move between its first and second positions. Similarly, second  52  and third  54  wall portions cooperatively define second plunger cavity  58 , within which the second plunger  24  is disposed and able to move between its first and second positions. 
     Also in the illustrated embodiment, housing  12  defines first  60  and second  62  rails that are disposed outside of the internal chamber  40  and above a main external surface  64  of the housing  12 . As best illustrated in  FIGS. 1A and 2A , control member  26  defines complimentary channels  64 ,  66  that receive the first  60  and second  62  rails. The interface between rails  60 ,  62  and channels  64 ,  66  allows the control member  26  to move slidably along the housing and affect the movement of the plungers  22 ,  24 , and the overall operation of the valve device  10 , as described above. 
     Also in the illustrated embodiment, housing  12  defines opening  70  between the internal chamber  40  and the environment external to the housing  12 . Cradle portion  48  is disposed through opening  70  such that a first portion of the cradle portion  48  is disposed within the internal chamber  40  and a second portion of the cradle portion  48  is disposed outside of the internal chamber  40 . 
     In the illustrated embodiment, housing  12  defines ancillary passageway  95  that is positioned proximal to the control member  26  and that is in fluid communication with the first inlet path  14 . Ancillary passageway  95  terminates in opening  97  on the external surface  64  of the housing  12 . While inclusion of the ancillary passageway  95  is considered optional, it is also considered advantageous for inclusion in valve devices intended to be used with suction because it provides a degree of manual control over the suction. For example, if inlet tubular member  28 , and therefore inlet path  14 , of valve device  14  were connected to a suction source, a clinician can use a finger, thumb or other item to cover opening  97 , effectively forcing the suction source to draw fluid through the inlet path  14  instead of through the ancillary passageway  95 . This provides an additional degree of control over the flow of fluid through the inlet path and the inlet tubular member, if included, of these particular valve devices. 
     Housing  12  can have any suitable size, shape and configuration, and a skilled artisan will be able to select an appropriate size, shape and configuration for a valve device according to a particular embodiment based on various considerations, including the intended use of the valve device. For example, in the illustrated embodiment, housing  12  has a cylindrical configuration with the opening  40  and control member  26  positioned toward the distal end of the valve device (toward the outlet path  18  in the figures). The inventors have determined that this configuration is suitable for valve devices intended to be used in hand-operated medical devices, such as suction/irrigation devices. 
     It is also noted that the housing can comprise a unitary member or can comprise two or more separate members that are attached to form the housing. For example, in the illustrated embodiment, housing  12  is formed of housing members  72 ,  74  that are attached to each other with a series of connectors  76 . In these embodiments, any suitable connectors can be used, including rivets, screws, adhesives, and the like. The housing submembers  72 ,  74  can also be structured to allow a mechanical interaction between them that is sufficient to provide the desired attachment. Also in the illustrated embodiment, cradle portion  48  is a separate member that is attached to the housing submembers  72 ,  74  to form housing  12 . Any suitable connectors can be used in attaching the cradle portion  48  to the housing submembers  72 ,  74 , including rivets, screws, adhesives, welds, and the like. Furthermore, any suitable technique or process can be used in attaching the cradle portion  48  to the housing submembers  72 ,  74 , including ultrasonic welding, gluing, riveting, screwing, and the like. The components can also be structured to allow a mechanical interaction between the cradle portion  48  and the housing submembers  72 ,  74  that is sufficient to provide the desired attachment. Alternatively, the cradle portion  48  can be defined by one or both of the housing submembers  72 ,  74 , or a unitary housing can define the cradle portion  48 . 
     Furthermore, housing  12  can be formed of any suitable material, and a skilled artisan will be able to select an appropriate material for a valve device according to a particular embodiment based on various considerations, including the intended lifespan of the valve device (e.g., single use v. reusable) and any treatment processes to which the valve device is expected to be exposed (e.g., sterilization processes). Examples of suitable materials include plastics and metals commonly used in the fabrication of medical devices and/or medical equipment. 
     As best illustrated in  FIGS. 3 and 4 , control member  26  defines first  76  and second  78  recesses that are sized and configured to receive a portion of the first  22  and second  24  plungers, respectively. In the illustrated embodiment, control member  26  includes a first ramped surface  80  that defines one wall of the first recess  76  and a second ramped surface  82  that defines one wall of the second recess  78 . The recesses  76 ,  78  are oriented opposite one another with respect to a hypothetical line  84  such that the ramped surfaces  80 ,  82  extend upward and away from each other. This arrangement of the recesses  76 ,  78  ensures that only one of the plungers  22 ,  24  is fully seated in its respective recess  76 ,  78  at any given time as the control member  26  is moved between its first, proximal and second, distal positions. In alternative embodiments, an example of which is illustrated in  FIG. 7 , each of the recesses  76 ′,  78 ′ defines a shoulder that forms a track, such as shoulders  77 ′ and  81 ′ and tracks  79 ′ and  83 ′. In these embodiments, each of the tracks  79 ′,  81 ′ receives a flange defined by or disposed on the upper portion of the respective plunger  22 ′,  24 ′. Thus, flange  27 ′ is received by track  79 ′ and flange  29 ′ is received by track  81 ′. Each of the flanges  27 ′,  29 ′ rides within the respective track  79 ′,  81 ′ such that the control member  26 ′ pushes the respective plunger  22 ′,  24 ′ upward and pulls the plunger  22 ′,  24 ′ downward with appropriate movement of the control member  26 ′, as described above. In these alternative embodiments, the tracks can be formed as recesses within the control member, as a recess defined between multiple pieces that are assembled to form the control member, or in any other suitable manner. These alternative embodiments avoid reliance on recoil of a tubular member compressed by a plunger to move the plunger back to its upper position. 
     The control member  26  illustrated in  FIG. 4  is suitable for use in valve devices in which it is desired to have fluid flowing through one of the inlet paths at any given time. As illustrated in  FIG. 4 , each of the recesses  76 ,  78  extends from hypothetical line  84 . Thus, any proximally- or distally-directed movement of the control member  26  relative to the hypothetical line  84  results in one of the plungers  22 ,  24  initiating movement into the respective plunger cavity  56 ,  58 . While this is desirable in some embodiments, an intermediate position in which fluid cannot flow through either inlet path may be desirable in others. For these embodiments, each of the recesses can be spaced from the hypothetical line by a suitable distance. For example, as illustrated in  FIG. 4A , an alternative control member  26 A can include recesses  76 A,  78 A, each of which extends from a point that is spaced from the hypothetical midline  84 A, providing an intermediate space  79 A between the two recesses  76 A,  78 A that does not define a recess. As a result, when this control member  26 A is positioned in an intermediate position, between its first, proximal position and its second, distal position, both plungers are maintained in their first position within the respective plunger cavities of the valve device, blocking fluid flow through each of the respective inlet paths. This structural arrangement can be scaled for control members that include more than two recesses, also by including an appropriate spacing between pairs of recesses. In these embodiments, individual pairs of recessed can all include a space of the same size, or different sizes. Some pairs can have no spacing, also, such as the recesses  76 ,  78  of the control member  26  illustrated in  FIG. 4 . This structural arrangement is considered advantageous at least because it provides an additional degree of control over fluid flow through the inlet paths. 
     It is noted that a valve device according to an embodiment can include more than two inlet paths that converge into a single outlet path. In these embodiments, the cradle portion defines the additional inlet path(s), and the control member defines additional recess(es).  FIG. 5  illustrates an alternative control member  26 ′ suitable for use in a valve device having three inlet paths. This control member  26 ′ defines first  76 ′, second  78 ′ and third  79 ′ recesses. The third recess  79 ′ is diposed between the first  76 ′ and second  78 ′ recesses with respect to both a lengthwise axis a 1  and a transverse axis a 2  of the control member  26 ′. The first  76 ′ and second  78 ′ recesses have structures similar to those in the control member  26  illustrated in  FIGS. 3 and 4 . Thus, control member  26 ′ includes a first ramped surface  80 ′ that defines one wall of the first recess  76 ′ and a second ramped surface  82 ′ that defines one wall of the second recess  78 ′. The recesses  76 ′,  78 ′ are oriented opposite one another with respect to transverse axis a 2  such that the ramped surfaces  80 ,  82  extend upward and away from each other. In this embodiment, control member  26 ′ also defines third  83 ′ and fourth  85 ′ ramped surfaces, each of which defines one wall of the third recess  79 ′. The third  83 ′ and fourth  85 ′ ramped surfaces are positioned such that each extends upward and toward the center of the third recess  79 ′. This arrangement of the recesses  76 ′,  78 ′,  79 ′ allows the control member  26 ′ to control fluid flow through three inlet paths and ensures that only one of three plungers in an associated valve device is fully seated in its respective recess  76 ′,  78 ′,  79 ′ at any given time as the control member  26 ′ is moved between first, proximal, intermediate, and second, distal positions. 
     While inclusion of inlet tubular members  28 ,  30  and outlet tubular member  32  is considered optional, inclusion of these components can be advantageous at least because it allows the valve device  10  to control fluid flow from and into remote locations. For example, one of the inlet tubular member  28  can be placed in fluid communication with a supply of an irrigation fluid and the other inlet tubular member  30  can be connected to a vacuum or others source of negative air pressure. When the outlet tubular member  32  is positioned at a desired point of treatment, the control member  26  can be moved between its first, proximal position and second, distal position to selectively deliver irrigation fluid to the point of treatment and apply suction to the point of treatment. 
     If included, inlet tubular members  28 ,  30  and outlet tubular member  32  can be formed from any suitable material and can have any suitable configuration. A skilled artisan will be able to select an appropriate material and configuration for each based in a valve device according to particular embodiment based on various considerations. The inventors have determined that inlet tubular members  28 ,  30  formed of a flexible and resilient material, such as a polymeric material, are advantageous at least because the plungers can pinch tubular members formed of such materials when blocking fluid flow through the tubular member is desired, and the tubular member easily restores itself to an open configuration when the plunger moves from its first position to its second position, effectively removing the pinching effect. Indeed, these tubular members can ensure that the plunger remains in its second position, which allows fluid flow through the tubular member, until the control member moves the plunger to its first position and pinches the tubular member. Examples of suitable materials for the inlet tubular members include silicone tubing known in the art. The inventors have also determined that a metal tubular member, such as a stainless steel tubular member, is suitable for the outlet tubular member at least because the rigidity of such a tubular member provides desirable handling characteristics when delivering fluid to and taking fluid away from a point of treatment. Other examples of suitable materials for the outlet tubular member include polymer-like rigid nylon, polyether ether ketone (PEEK), cobalt chromium, nickel titanium alloys, and others. 
     Also, if included, inlet tubular members  28 ,  30  and outlet tubular member  32  can have any suitable size, shape and configuration, and a skilled artisan will be able to select an appropriate size, shape and configuration for each included tubular member in a valve device according to a particular embodiment based on various considerations, including the fluids with which the valve device is intended to be used and the point or points of treatment at which the valve device is intended to be used. If included, inlet tubular members are advantageously elongate tubular members having a circular or ovoid cross-sectional shape and inner passageway cross-sectional shape. If included, the outlet tubular member advantageously defines a structural feature, such as a bend, curve, curves, helix or other structural feature that facilitates placement of the distal end, and distal opening, of the outlet tubular member in or near the point of treatment at which the particular valve device is intended to be used. For example, in the first example embodiment and as best illustrated in  FIGS. 1 and 2 , it is considered advantageous to include a bend  90  in the outlet tubular member  32  to facilitate placement of the distal end  92  of the outlet tubular member  32  in or near a sinus passageway of a patient during sinus surgery and/or to allow for spatial separation of a clinician&#39;s hands when using both the valve device  10  and another device, such as a scope, in a procedure. If included, bend  90  can have any suitable angle, and a skilled artisan will be able to select an appropriate angle for a valve device according to a particular embodiment based on various considerations, including the tortuosity of the body cavity, passageway or other feature leading to or containing the point of treatment at which the valve device is intended to be used. As illustrated in  FIGS. 1 and 2 , bend  90  can have an angle α that maintains the axis of the passageway defined by the outlet tubular member  32  on a single plane and that is between about 90° and about 180°. Other examples of suitable angles include angles between about 115° and about 150°, and an angle of about 135°. 
       FIGS. 6A, 6B and 6C  illustrate a second example valve device  110 . The second example valve device  110  is similar to the first example valve device  10  illustrated in  FIGS. 1, 1A, 1B, 2, 2A and 2B , except as described below. Thus, valve device  110  includes a housing  112 , first  114  and second  116  inlet paths, outlet path  118 , and junction  120  joining the first  114  and second  116  inlet paths and the outlet path  118 . A first plunger  122  is partially disposed in the first inlet path  114  and is movable between first and second positions. Similarly, a second plunger  124  is partially disposed in the second inlet path  116  and is movable between first and second positions. A control member (not illustrated in the  FIGS. 6A, 6B and 6C ) is slidably disposed on the housing  12 . For this embodiment, control member  26 ′ illustrated in  FIG. 5  is suitable for inclusion in the valve device  110 . 
     In this embodiment, the cradle portion  148  of the housing  112  defines a third inlet path  117  that is in fluid communication with the junction  120 . Also, the valve device  110  includes a third plunger  125  that is partially disposed in the third inlet path  117  and is movable between first and second positions similar to the first  122  and second plungers  124 . Thus, in this embodiment, movement of the control mechanism from a first, proximal position to a second, intermediate position, to a third, distal position produces selective, individual movement of the first  122 , second  124 , and third  125  plungers. In turn, this allows a user to selectively control through which of the first  128 , second  130  and third  131  inlet tubular members fluid flow is allowed to pass at any given time to the junction  120  and, ultimately the outlet tubular member, or in the opposite direction. 
     In  FIG. 6A , control member (not illustrated) is in a first, proximal position. In this position, the control member maintains the first  122  and third  125  plungers in their first positions by blocking these plungers  122 ,  125  from moving to their second position. The second plunger (not visible in  FIG. 6A ), however, is able to move to its second position. As a result, fluid flow through the first  114  and third  117  inlet paths is blocked while the second inlet path  116  is open to fluid flow. 
     In  FIG. 6B , control member (not illustrated) is in a second, intermediate position. In this position, the control member maintains the first  122  and second  124  plungers in their first positions by blocking these plungers  122 ,  124  from moving to their second position. The third plunger (not visible in  FIG. 6B ), however, is able to move to its second position. As a result, fluid flow through the first  114  and second  116  inlet paths is blocked while the third inlet path  117  is open to fluid flow. 
     In  FIG. 6C , control member (not illustrated) is in a third, distal position. In this position, the control member maintains the second  124  and third  125  plungers in their first positions by blocking these plungers  124 ,  125  from moving to their second position. The first plunger (not visible in  FIG. 6C ), however, is able to move to its second position. As a result, fluid flow through the second  116  and third  117  inlet paths is blocked while the first inlet path  114  is open to fluid flow. 
     The foregoing detailed description refers to example valve devices and includes the best mode for practicing the invention. The description and the appended drawings illustrating the described devices are intended only to provide examples and not to limit the scope of the claims in any manner.