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RELATED APPLICATION 
     The present application is a continuation-in-part of U.S. patent application Ser. No. 10/814,437, filed on Mar. 30, 2004, entitled HAND-OPERABLE PISTON PLUNGER. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a pump for displacing a fluid. More specifically, the present invention relates to a pump including a plunger assembly that is coupled to a valve assembly to form the pump. 
     BACKGROUND 
     Plungers are commonly used for unclogging blocked drains. The basic plunger consists of a rubber suction device mounted on a handle. This basic plunger, while effective for many clogs, has its associated problems. These problems include limited suction power to dislodge clogs and a tendency to displace a high volume of water/fluid, both when first inserted and then during actual plunging action. As a result, splashing and/or overflow of drain liquid/fluid may result. In an attempt to at least increase the available suction power for a plunger, an accordion/bellow section has been added to many versions to increase the change in volume and thereby the amount of pressure which may be generated with the plunger. 
     There are many circumstances in which the common plunger cannot dislodge the clog within a drain. As a result, there are a series of power plungers which have been developed. Such power plungers generally use a pressurized fluid source or water flow via a pump mechanism to create a positive fluid pressure against the clog. Such power plungers have generally proven to be more effective against tough clogs. However, an obvious potential drawback of such a power plunger is that the addition of more fluid to an already clogged drain may alone cause overflow. Additionally, such power plungers are generally complex in nature and usually require a hookup with another fluid or water source. 
     What is needed in the art is a hand-operable plunger which is self contained, simple to use, and which is able to create a positive pressurized fluid flow against a clog to thereby increase its effectiveness in dislodging clogs. Also, the hand-operable plunger can be coupled to a valve assembly to form a hand-operable pump for displacing fluid. 
     SUMMARY 
     The hand-actuated piston plunger of the present invention is configured to use clog fluid already present in a plumbing unit having a backed-up drain to thereby create a pressurized injection fluid stream to be directed at a clog. The hand-actuated piston plunger can also be coupled to a valve assembly allowing them both, in one illustrative embodiment, to function together as a pump. 
     The hand-actuated piston plunger of the present invention includes a vessel member, a drain adaptor, a plunger piston, and a piston actuator. Such a plunger may further advantageously be equipped with an actuator handle, a vessel handle, and/or a bellow/accordion arrangement within the vessel member. The vessel member has first and second vessel ends and a hollow vessel interior. The drain adaptor is associated with the first vessel end and includes an adaptor opening which facilitates selective flow of fluid relative to the vessel interior. The piston plunger is slidably mounted within the vessel interior and is movable relative to the drain adaptor. The piston actuator has a first and second end with the first end operably associated with the plunger piston. The second end of the piston actuator extends outside of the vessel interior. This piston actuator can then be used to move the plunger piston within the vessel interior in such a manner so as to selectably either draw clog fluid into the vessel interior or to expel it therefrom. The provision of actuator and/or vessel handles allow for greater control during use of the plunger of the present invention. A bellows/accordion arrangement positioned within the vessel interior and interconnecting the first vessel end and the plunger piston provides for a changeable yet sealed working volume for the clog fluid. 
     In another illustrative embodiment, a plunger piston can be coupled with a valve assembly to form a pump. The valve assembly includes a body having first and second openings disposed therein. The valve assembly also includes at least first and second valves with each disposed adjacent first and second openings, respectively. The valves are configured to allow fluid flow in only one direction. The body is configured to be coupled to the plunger piston. In this illustrative embodiment, the body includes an extension member connected to the first opening and extending outwardly therefrom. The extension may be placed in a fluid desired to be displaced and then the piston is selectively actuated in an appropriate direction to draw fluid into the pump. The first valve adjacent the first opening is configured to allow fluid to be drawn in, but not to be expelled through the first opening. Once a fluid is drawn into the pump through the first opening, the piston can be actuated in another direction to expel the fluid from the pump. The second valve is configured to allow the fluid to be expelled from the pump through the second opening. The first valve prevents the fluid from exiting through the first opening. An extension member can be coupled to the second opening to further conduct the fluid from the pump before being expelled into the outside environment. 
     In another illustrative embodiment, flexible tubular members can be coupled to each opening in the valve assembly. These flexible tubular members can be of various lengths to allow placement in a fluid disposed at various distances from the pump and allow the fluid to be expelled remotely from the pump. In another illustrative embodiment the valve assembly is coupled to the piston plunger through an interference fit, allowing the valve assembly to be quickly removed or coupled to the piston plunger. The bellows/accordion arrangement can be used in other illustrative embodiments to change the volume of the piston plunger to vary the amount of fluid to be displaced. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The present invention will be described hereafter with reference to the attached drawings which are given as non-limiting examples only, in which: 
         FIGS. 1–3  are schematic sectional views of a first embodiment of the piston plunger of the present invention, illustrating three stages of operation thereof, 
         FIG. 4  is a schematic sectional view of the vessel member of the piston plunger of the present invention carrying a piston there within and having a first embodiment of a vessel handle affixed thereto; 
         FIG. 5  is a schematic, partial sectional view of a vessel member of the piston plunger of the present invention with the vessel member having a piston positioned there within and having a second embodiment of the vessel handle attached thereto; 
         FIG. 6–8  are schematic sectional views of a second embodiment of the piston plunger of the present invention, illustrating three stages of operation thereof; and 
         FIG. 9–10  are schematic sectional views of an embodiment of the piston plunger of the present invention which incorporates a bellows/accordion structure therewithin, illustrating the two primary stages of operation thereof. 
         FIG. 11  is a schematic sectional view of an illustrative embodiment of a pump. 
         FIG. 12  is another schematic sectional view of the illustrative embodiment of the pump of  FIG. 11 . 
         FIG. 13  is another schematic sectional view of the illustrative embodiment of the pump of  FIG. 11 . 
         FIG. 14  is another schematic sectional view of the illustrative embodiment of the pump of  FIG. 11 . 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate at least one preferred embodiment of the present invention in one form, and such exemplifications are not to be construed as limiting the scope of the present invention in any manner. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Hand-operable piston plunger  20 , illustrated in various stages of operation in  FIGS. 1–3 , represents a first embodiment of the plunger of the present invention. Hand-operable piston plunger  20  is configured for freeing a clog  22  within the piping/drain  24  associated with a particular plumbing unit  26  (e.g., a toilet or sink) using clog/back-up fluid  28  already collected within plumbing unit  26 . Hand-operable piston plunger  20  includes a vessel member  30 , a plunger piston  32 , a piston actuator  34 , a vessel handle  38 , and an actuator handle  40 . 
     Vessel member  30  has a vessel interior  42 , and through operation of the combination of the plunger piston and piston actuator, it is configured for selectively receiving clog/back-up fluid therewithin. The vessel interior  42  must be large enough to hold a suitable amount of fluid (as best seen in  FIG. 2 ) for the plunging of difficult clogs  22 . The vessel member  30  is advantageously made of a plastic material as such materials generally are relatively inexpensive, chemically and mechanically durable, and generally easy to clean. Alternatively, vessel member  30  could be made of a durable, corrosion/rust resistant metal or other material. It is very useful for a vessel member  30  to be made of rust and corrosion resistant material so as to thereby retain, long-term, a smooth surface on the vessel interior  42  to allow for easy piston movement therewithin. 
     Vessel member  30  further includes a first vessel end  44  and a second vessel end  46 . Associated with first vessel end  44  is a first end stop  48 , while second vessel end  46  has a second end stop  50  associated therewith. First end stop  48  and second end stop  50  together provide the travel limits for piston  32  within vessel interior  42 . First end stop  48  must be supplied with at least one first stop opening  52  to allow fluid communication between drain adaptor  36  and vessel member  30 . In this first embodiment, the first end stop  48  is integrally attached to drain adaptor  36  and as such may further be one of integrally or separably attached to first vessel end  44 . It is to be understood that first end stop  48  could take the form of a ledge, a pin, a set of pins, or some sort of spider web arrangement connected to first vessel end  44  to provide for the necessary stop feature for end stop  48 . As such, first end stop  48  need not necessarily be a part of drain adaptor  36 . 
     Second end stop  50 , as shown, is in the form of an end cap which is mechanically releasably attached to second vessel end  46 . It is to be understood that other possible configurations for second end stop  50  may be chosen, although not shown as part of this particular embodiment. Specifically, vessel member  30  can be an essentially open container without a lid as long as the function of the second end stop  50  is provided for (i.e., plunger piston  32  is not able to escape from second vessel end  46  during upward operation of piston plunger  32 .). 
     At minimum this limit stop requirement for second end stop  50  could be provided for simply by the presence of an inwardly extending ledge or pin(s) (not shown) at second vessel end  46 . However, it is advantageous that second end stop  50  also be able to provide lateral support for piston actuator (plunger shaft)  34  during operation thereof. One means of providing for this feature is for second end stop  50  to have a “spider” arrangement which leaves an appropriate size opening for receiving the plunger shaft/piston actuator therewithin. It is to be understood that the cap version for second end stop  50 , as shown in  FIGS. 1–3 , satisfies this desired support/stability function for second end stop  50 . 
     The plunger piston  32  of the first embodiment, as shown in  FIGS. 1–3 , is slidably mounted against vessel interior  42 . It is important in such an embodiment for plunger piston  32  to retain a seal against vessel interior  42  as well as maintaining a seal therewith during operation. This is such that unwanted leaking of the clog fluid  28  to regions above plunger piston  32  can be avoided, and so that the pressure associated with the operation of piston  32  can be most effectively maintained. It is useful that plunger piston  32  be made of a plastic or polytetrafluoroethalene (PTFE, sold under the trade name Teflon™) or potentially of a corrosion resistant metal. 
     The material chosen must be able to allow for easy motion of the piston  32  yet maintain an appropriate seal with vessel interior  42 . Additionally, such a material must be rust and corrosion resistant since active drying of the vessel interior after use thereof is not always feasible. As such, the vessel interior  42  and plunger piston  32  can be expected to be subjected to exposure to moisture for generally long periods of time after use of the plunger  20 . Additionally, the plunger piston  32  should be chemically resistant to most household cleaners, drain opening solutions, and/or disinfectants to which plunger  20  may be exposed, either during use or cleaning thereof. 
     To provide for a better seal between plunger piston  32  and vessel interior  42 , an additional seal member such as an o-ring seal  54  ( FIG. 4 ) may be supplied. Such a seal would better ensure the integrity of the seal between piston  32  and vessel member  30 . This is especially true if a metal piston  32  is being employed, since the coefficient of friction associated with a metal piston can be expected to decrease with the formation of any sort of corrosion or any mechanical wear on the surface thereof. 
     Plunger piston  32 , along with vessel interior  42  and first vessel end  44 , define a variable fluid volume V within vessel member  30 . This volume V will of course be dependent upon the positioning of piston  32 . The expansion of volume V via movement of plunger piston  32  toward the second vessel end  46 , will draw fluid into the vessel interior  42  via drain adaptor  36 . Conversely, the movement of plunger piston  32  toward first vessel end  44  will serve to contract volume V and expel fluid from piston plunger  20 . The faster plunger piston  32  is moved, the more force with which fluid (e.g., air, liquid, suspension, etc.) is able to be drawn or expelled. 
     By having plunger piston  32  positioned adjacent first vessel end  44  prior to insertion of piston plunger  20  into plumbing unit  26  and into clog fluid  28 , clog fluid  28  can then be drawn into the vessel interior  42  upon insertion of drain adaptor  36  into clog fluid  28 . The volume V of clog fluid  28  within vessel interior  42  can be then increased to its maximum by movement of plunger piston  32  towards second vessel end  46 , thereby providing the fluid for use by the piston plunger  20  to free the clog and creating volume space for the insertion of piston plunger  20  into position proximate the piping/drain  24 . 
     Once drain adaptor  36  is appropriately positioned relative to drain  24 , piston actuator  34  is pressed forcefully downward. This downward motion causes plunger piston  32  to rapidly expel the clog fluid  28  out of the vessel interior  42  and through drain adaptor  36  and into drain  24 . This expelled fluid  28  acts upon the clog  22  and, when successful, provides enough force to cause the clog to free from the piping/drain  24  and thereby allow the entirety of clog fluid  28  to proceed down through drain  24 . 
     Drain adaptor  36  is releasably attached or molded to first vessel end  44 . Drain adaptor  36  is configured such that it creates a fluid connection of the vessel interior  42  with the exterior of the piston plunger  20  and allows for a fluid connection to be made with the drain fluid in the plumbing unit  26  and/or drain  24 . Drain adaptor  36  is advantageously removably attached for periodic, more vigorous cleaning and to permit replacement thereof is necessary due to air. 
     There are certain advantages gained by having drain adaptor  36  having a conical or frusto-conical shape. First of all, such a conical shape allows drain adaptor  36  to fit into various diameter drains  24 . Thus, it eliminates the need to change adaptors  36  to accommodate different drain sizes. Additionally, the conical shape helps create a venturi nozzle effect during expulsion of clog fluid  28  through the drain adaptor  36 , thereby increasing the effective ejection speed which may be achieved. 
     Drain adaptor  36  is preferably made of rubber or another elastomeric material. By being made of such a material, it aids in the insertion of drain adaptor  36  into a given drain opening. The highly elastic nature of such a material helps to accommodate the forces applied to the adaptor  36  due to the suction and ejection processes. Finally, elastomeric materials are generally reasonably inert and thereby can withstand exposure to a variety of household chemicals, including drain opener chemicals, which may have been added to the clog fluid  28 . 
     Piston actuator  34  connects to plunger piston  32  within vessel interior  42  and extends through second vessel end  46  so as to provide a portion thereof available for actuation by hand. Such a piston actuator  34  is an elongate member that can be made of any of a variety of materials including wood, metal, or plastic. The variety of materials available for use of the piston actuator are more varied than those available for the other portions as the exposure of the piston actuator to clog fluid  28 , including any drain cleaner added thereto, is limited since it is placed on the dry side of piston  32 . It is important that the material chosen for piston actuator  34  be mechanically durable and strong to obtain an appropriate transfer of mechanical power to piston  32  for effective plunging. 
     Piston actuator  34  has some significant functional differences when compared to the prior art handle associated with a standard plunger. The standard prior art plunger is affixed on top of a suction member and is arranged so that the first plunging step, once the suction device is entered into the water, is to move the drain-adapting suction device downwardly toward and into contact with drain  24 . This first step is different from that for the piston actuator of the  34  of the present invention. Specifically, actuator  34  is intended first to be moved upwardly away from first vessel end  44  in order to draw water into the vessel interior  42 . It is not until an appropriate amount of fluid  28  has been drawn into vessel interior  42  that the piston actuator  34  is then forced downwardly toward first vessel end  44  to cause fluid expulsion via the use of plunger piston  32 . Additionally in the present invention, the function of piston actuator  34  is solely to move piston  32  relative to vessel interior  42 . It is not the function of piston actuator  34  to move drain adaptor  36  into its appropriate location. Instead, drain adaptor  36  is moved using vessel handle  38 . 
       FIGS. 4 and 5  help to illustrate two different embodiments for the vessel handle, the first embodiment vessel handle  38 , as shown with the embodiment shown in  FIGS. 1–3 , and the second embodiment vessel handle  56 , as illustrated in  FIG. 5 . Vessel handle  56 , shown in  FIG. 5 , is configured to allow more vertical pressure to be applied to the seal contact area between drain  24  and drain adaptor  36 . The longer version for the first embodied handle, vessel handle  38 , may prove useful in allowing any of a range gripping positions relative to the length of vessel member  30  to be grabbed by a user, potentially allowing for greater control of the placement of drain adaptor  38  relative to a particular drain  24 . This extra length can especially prove useful when using the piston plunger  20  relative to a sink where the clog fluid  28  may not raise such a concern with respect to potential contact therewith. In any event, it is this handle  38 ,  56  which is used to appropriately locate drain adaptor  36  relative to a drain  24  and to create a sufficient seal between adaptor  36  and that drain  24  to promote an effective plunging operation. 
     A second embodiment of the piston plunger is illustrated in  FIGS. 6–8  in the form of piston plunger  60 . Only those portions thereof which differ from the parts presented with respect to piston plunger  20  are labeled differently than the corresponding parts associated with piston plunger  20 . Further, it is only those differing parts which are described in detail with respect to piston plunger  60 . Additionally, the general method of operation of plunger  60 , as indicated in  FIGS. 6–8 , is essentially the same as that presented for the first embodiment in  FIGS. 1–3 . 
     The two primary structural differences related with respect to piston plunger  60  are drain adaptor  62  and actuator handle  64 . Drain adaptor  62  is bell shaped in nature and generally provides a wider opening for a positioning proximate drain  24 . As such, it is possible for a larger amount of fluid to be taken in or expelled via adaptor  62  at any given time. Additionally, the bell shaped nature of the adaptor  62  provides for a more significant amount of sealing area adjacent drain  24  and plumbing unit  26  than is possible using conical drain adaptor  36  of the first embodiment. 
     The size and shape of actuator handle  64  offers certain advantages over the simpler actuator handle  40  of the first embodiment. For one, it provides a larger and potentially more ergonomic gripping zone, while still providing a similar grip end that is similar to that associated with actuator handle  40 , in the instance that a user may be more comfortable with that style of a grip. Additionally, the handle bar style grip with the wide ends helps to ensure that the handle will be held outside of second vessel end  46  and stopped from entry into vessel interior  42  due to the interaction of handle  64  with second end stop  50 . 
       FIGS. 9 and 10  generally illustrate the two stages of use for the third embodiment of the present invention, generally labeled as piston plunger  70 . Piston plunger  70  includes a vessel member  72  with a vessel handle  74  affixed thereto and an accordion/bellow structure  76 . Accordion/bellow structure  76  has first and second structure ends  80  and  82  and an intermediate folding interconnect portion  84  therebetween. First and second structure ends  80 ,  82  and folding interconnect  84  thereby define a variable interior volume V′  78  within the accordion/bellow structure  76 . First structure end  80  has a first end opening  85  associated therewith to allow fluid connection between accordion/bellow structure  76  and an appropriate drain adaptor (not shown). Accordion/bellow structure  76  is an integral structure such that all of the parts associated therewith are integral with one another. Accordion/bellow structure  76  is ideally formed of an elastomeric material or at least a highly elastic polymeric material to thereby accommodate the compression and extension of the folding interconnect  84 . 
     The second structural end of accordion/bellows structure  76  includes portions which serve the same functional purposes as plunger piston  32 , piston actuator  34 , and actuator handle  40 . Specifically, second structure end  82  effectively includes a piston surface  86 , a bellows actuator  88 , and a bellows handle  90 . The inner surface of second structural end  82  can be considered to be a piston surface  86  as it is this surface which is able to act in a similar manner as the fluid side of plunger piston  32  of the other embodiments, in both the suctioning and the expulsion of a fluid relative to interior volume V′. 
     The accordion/bellow structure  76  of piston plunger  70 , as indicated in  FIGS. 9 and 10 , is configured such that the expansion of folding interconnect  84  from its compressed version shown in  FIG. 9  to its fully expanded version shown in  FIG. 10  allows for a change in volume of approximately 0.56 gallons. This volume change thereby represents the approximate potential intake that can be achieved during expansion of interior volume V. 
     It is to be understood that folding interconnect  84  provides for a built-in piston travel stop for the expansion of the accordion/bellow structure. This is true as folding interconnect  84  is integrally attached to each of first and second structure ends  80 ,  82 . Thus, folding interconnect  84  can be considered to be another appropriate travel stop means relative to the second vessel end. 
       FIG. 11  shows a sectional schematic view of an illustrative embodiment of pump  100 . Pump  100  includes piston plunger assembly  102  and valve assembly  104 . Plunger assembly  102  includes various components similar to that of hand-operable piston plunger  20  shown in  FIGS. 1–3 . Some of these include vessel  106 , which has vessel interior  108 , piston  110 , piston actuator  112 , and actuator handle  114 . Vessel handle  116  is coupled to vessel  106 . Piston  110  is actuated within vessel  106  by actuator  112  and actuator handle  114 . End stops  118 ,  120  prevent piston  110  from traveling out of vessel  106  during actuation. Plunger assembly  102  also includes adaptor  122 , which is similar to drain adaptor  36  shown in  FIGS. 1 through 3 . Plunger assembly  102  functions in a manner similar to that of plunger  20 . 
     Valve assembly  104  can be coupled to plunger assembly  102  so that assemblies  102 ,  104  function together as pump  100 . The illustrative embodiment of  FIGS. 12 through 14  show plunger assembly  102  and valve assembly  104  coupled to one another through an interference fit. As shown in  FIG. 11 , valve assembly  104  includes cylindrically-shaped body  124 . Body  124  includes hollow interior  126 . Valve assembly  104  also includes openings  128 ,  130 . In this embodiment, opening  128  is shown to be disposed in bottom  132  of body  124  and opening  130  is disposed through wall member  134  of body  124 . Adjacent each opening  128 ,  130  is disposed a valve  136 ,  138 , respectively. 
     Valves  136 ,  138  are configured to allow pump  100  to draw in a fluid, such as fluid  139 , through opening  128  and into body  124  and vessel  106  then be expelled through opening  130 . As shown in  FIG. 11 , extension member  137  can be coupled to opening  128  allowing fluid  139  to be drawn therein from receptacle  141 . In this illustrative embodiment, extension member  137  is shown to be rigid and tubular in shape, but other types of extension members can be used, such as flexible hoses of various lengths. Opening  130  can be similarly coupled to various types of extension members, such as extension member  137 , for example, with the length of the extension member determining how far from body  124  fluid is to be displaced.  FIG. 12  shows pump  100  with plunger assembly  102  and valve assembly  104  coupled to one another and in position to draw in fluid. 
       FIG. 13  shows a sectional schematic view of pump  100  being used to draw fluid therein. Extension member  137  is shown extending into fluid  139 .  FIG. 13  also shows piston  110 , actuator  112 , and handle  114  being actuated in direction  140 . Piston  110  includes a seal  142  disposed thereon, allowing suction to be created when piston  110  is actuated in direction  140 . The suction causes valve  136  to open in direction  145  and fluid  139  is drawn up through extension member  137  and into pump  100  as illustrated by path  143 . Fluid  139  moves into body interior  126  continues through adaptor opening  146  into vessel interior  108  while suction is present. Valve  138  is prevented from opening by stop member  147  when fluid is being drawn into pump  100 . 
     Whenever piston  110  is stopped by end stop  118 , or a desired amount of fluid is drawn into pump  100 , handle  114  may be used to actuate actuator  112  and piston  110  in direction  150  as shown in  FIG. 14 . When piston  110  is actuated in direction  150 , the drawn-in fluid in vessel interior  108  is expelled through adaptor opening  146 . Stop member  149  prevents valve  136  from being actuated in a direction opposite direction  145 . Valve  138  can only be actuated in direction  153 , causing fluid  139  to be expelled through opening  130  along path  153 . After expulsion, pump  100  can again draw fluid in through opening  128  through actuation of piston  110  in direction  140  and expel it through opening  130  through actuation of piston  110  in direction  150 . 
     Although the present invention has been described with reference to particular means, materials and embodiments, from the foregoing description, one skilled in the art can easily ascertain the essential characteristics of the present disclosure and various changes and modifications may be made to adapt the various uses and characteristics without departing from the spirit and scope of the present invention as set forth in the following claims.

Summary:
A pump having a vessel with a hollow interior. An adaptor may be associated with the vessel and include an opening that facilitates selective flow of fluid relative to the interior. A piston may be slidably mounted within the vessel&#39;s interior and movable relative to the adaptor. The pump may also include a piston actuator having a first actuator end and a second actuator end in which the first actuator end is operably associated with the piston. The second actuator end may extend outside the interior such that the piston actuator is configured for facilitating selectable movement of the piston within the vessel. A valve assembly selectively attachable to the adaptor to facilitate selective flow of fluid relative to the adaptor.