Abstract:
A filter canister is disclosed that includes a main body having a top. An inlet port is positioned on the top of the main body and an outlet port also positioned on the top of the main body, offset from the inlet port by a predetermined distance. A filter cartridge is positioned within the main body that has an outlet end that sealingly engages the outlet port. An inlet port identifier is associated with the inlet port, and an outlet port identifier is associated with the outlet port. A valve is also disclosed that operates in connection with the filter canister.

Description:
This application claims the benefit of the filing dates of U.S. provisional application No. 60/152,924 filed on Sep. 9, 1999 and U.S. Provisional application No. 60/192,360 filed on Mar. 27, 2000. 
    
    
     FIELD OF THE INVENTION 
     The present invention concerns a filter and valve apparatus. More specifically, the present invention concerns an encapsulated filter that cooperates with an easy shut-off valve to permit rapid replacement of the encapsulated filter. The filter and valve assembly of the present invention are designed to prevent or minimize the spillage of the filtration medium during the filter exchange operation. 
     BACKGROUND OF THE INVENTION 
     Filtration systems known in the prior art generally include a cylindrical housing into which a cylindrical filter is placed to filter particulate materials from fluids such as water. In such prior art systems, in order to replace a clogged or dirty filter, it is first necessary to shut off the fluid supply to the filter housing, open the housing and replace the filter. Not only is this operation time consuming, it usually results in leakage of fluid when the housing is opened. Accordingly, a need has developed for a filter system that permits rapid exchange of the filter element without the associated spillage of fluid from the filter housing. This is particularly desirable in situations where the filter is replaced in a sterile environment, such as an operating room in a hospital or such as a clean room in a manufacturing facility, where any spilled filtration media must be cleaned up according to rigid procedures. 
     SUMMARY OF THE INVENTION 
     The present invention overcomes the problems with the prior art by providing a self-contained, replaceable filter cartridge that can be quickly and easily removed and replaced from the fluid lines connected thereto. 
     To accomplish this, the present invention provides a valve that connects a filter cartridge to the fluid being filtered. The valve design permits the cartridge to be quickly replaced without spilling fluid into the environment by providing fluid cut-off upon rotation of filter and part of the valve head assembly. The cartridge may be either a completely disposable type or it may have a construction where the housing may be opened to provide access to an internal, disposable filter. 
     In accordance with the teachings of the present invention, a filter canister is provided having a main body with a top. An inlet port is positioned on the top of the main body along with an outlet port that is displaced from the inlet port by a predetermined distance. A filter cartridge is positioned within the main body with an outlet end that sealingly engages the outlet port. An inlet port identifier is associated with the inlet port and an outlet port identifier is associated with the outlet port. 
     The present invention further provides that the inlet port identifier be a flange positioned on the inlet port with a first diameter. The outlet port identifier on the outlet port is a flange with a second diameter. The first diameter can be larger than the second diameter or vice versa. 
     Alternatively, the inlet port identifier may be a flange with a first shape. The outlet flange identifier may be a flange with a second shape. To differentiate between the inlet port and the outlet port, the flanges may be of different shapes. 
     The present invention also provides for a valve having an upper plate with inlet and outlet ports. A receptacle disk is rotatably connected to the upper plate and also has inlet and outlet ports. The receptacle disk inlet and outlet ports fluidly communicate with the upper plate inlet and outlet ports when the receptacle disk in a first orientation with respect to the upper plate. The inlet and outlet ports do not fluidly communicate with one another when the receptacle plate is in a second orientation with respect to the upper plate. A lower disk has a cammed surface that permits access to the receptacle disk inlet and outlet ports when the receptacle disk is in the second orientation but prevents access to the receptacle inlet and outlet ports when the receptacle disk is in the first orientation. 
     In further accordance with the teachings of the present invention, the lower disk is connected to the upper plate in fixed relation thereto. The receptacle disk includes an inlet port identifier associated with the receptacle disk inlet port and an outlet port identifier associated with the receptacle disk outlet port. The inlet port identifier is a first flange receiving portion with a first diameter. The outlet port identifier comprises a second flange receiving portion with a second diameter. 
     In still further accordance with the teachings of the present invention, the first diameter is greater than the second diameter. Alternatively, the second diameter is greater than the first diameter. 
     According to the present invention, the inlet port identifier may alternatively have a first flange receiving portion with a first shape and a second flange receiving portion with a second shape. The first shape differs from the second shape. 
     According to still another teaching of the present invention, the inlet port identifier may comprise a diameter of the receptacle disk inlet port and the outlet port identifier may comprise a diameter of the receptacle disk outlet port. The diameter of the receptacle disk inlet port may be greater than the diameter of the receptacle disk outlet port or vice versa. 
     In still another embodiment of the present invention, a filter and valve assembly are provided where the filter has a main body with a top. Inlet and outlet ports are positioned on top of the main body and are offset from one another a predetermined distance. A filter cartridge, positioned within the main body, has an outlet end sealingly engaging the outlet port. A valve is also provided that has an upper plate with an inlet port and an outlet port. A receptacle disk, rotatably connected to the upper plate, has an inlet and an outlet port. The receptacle disk inlet and outlet ports fluidly communicate with the upper plate inlet and outlet ports when the receptacle disk is in a first orientation with respect to the upper plate. The receptacle disk inlet and outlet ports do not fluidly communicate with one another when the receptacle disk is in a second orientation with respect to the upper plate. A lower disk has a cammed surface that permits access to the receptacle disk inlet and outlet ports when the receptacle disk is in the second orientation and prevents access to the receptacle inlet and outlet ports when the receptacle disk is in the first orientation. The assembly also includes an inlet port identifier associated with the filter canister inlet port and the receptacle inlet port, where the inlet port identifier permits the filter canister inlet port to fluidly engage the receptacle disk inlet port. Also, the assembly includes an outlet port identifier associated with the filter canister outlet port and the receptacle disk outlet port where the outlet port identifier permits the filter canister outlet port to fluidly engage the receptacle disk outlet port. 
     Another object of the present invention is to provide a filter and valve assembly where the inlet port identifier is a first flange on the filter canister inlet with a first diameter and a first flange receiving portion on the receptacle disk inlet port for engaging the first flange. The outlet port identifier has a second flange on the filter canister outlet port with a second diameter and a second flange receiving portion on the receptacle disk outlet port for engaging the second flange. The flanges may be of differing sizes or shapes, as described above. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partial cross-sectional view of one embodiment of the filter cartridge according to the teachings of the present invention; 
     FIG. 2 is an end view illustration of the filter cartridge illustrated in FIG. 1; 
     FIG. 3 is a partial cross-sectional view of a second embodiment of a filter cartridge according to the teachings of the present invention as illustrated in FIG. 1; 
     FIG. 4 is an end view illustration of the filter cartridge illustrated in FIG. 3; 
     FIG. 5 is a partial cross-sectional view of a third embodiment of a filter cartridge according to the teachings of the present invention; 
     FIG. 6 is an end view illustration of the filter cartridge illustrated in FIG. 5; 
     FIG. 7 is a partial cross-sectional view of a fourth embodiment of a filter cartridge according to the teachings of the present invention; 
     FIG. 8 is an end view illustration of the filter cartridge illustrated in FIG. 7; 
     FIG. 9 is a cross-section of one embodiment of a valve according to the present invention taken along the cross-section line illustrated in FIG. 10; 
     FIG. 10 is a bottom view of the valve illustrated in FIG. 9; 
     FIG. 11 is a cross-section of the valve in FIG. 9, taken along a plane perpendicular to the cross-sectional view shown in FIG. 9; 
     FIG. 12 is a top view of the valve shown in FIG. 9; 
     FIG. 13 is a cross-sectional view of a second embodiment of the valve illustrated in FIGS. 9-10; 
     FIG. 14 is a bottom view of the valve shown in FIG. 13; 
     FIG. 15 is a cross-sectional view of a third embodiment of the valve illustrated in FIGS. 9-10; 
     FIG. 16 is a bottom view of the valve illustrated in FIG. 15; 
     FIG. 17 is a cross-sectional view of a fourth embodiment of the valve illustrated in FIGS. 9-10; 
     FIG. 18 is a bottom view of the valve illustrated in FIG. 17; 
     FIG. 19 is bottom view of the receptacle disk of the valve illustrated in FIGS. 9-10; 
     FIG. 20 is a cross-sectional view of the receptacle disk illustrated in FIG. 19; 
     FIG. 21 is a bottom view of one embodiment of the upper plate for the valve illustrated in FIGS. 9-10; 
     FIG. 22 is a partial cross-sectional side view of another embodiment of the filter canister of the present invention; 
     FIG. 23 is an end view of the filter canister shown in FIG. 22; 
     FIG. 24 is a cross-sectional view of another embodiment of a valve contemplated for use with the filter canister of the present invention; 
     FIG. 25 is a bottom view of the valve illustrated in FIG. 24; 
     FIG. 26 is a cross-sectional view of the valve illustrated in FIG. 24, the cross-section taken along a plane perpendicular to that in FIG. 24; 
     FIG. 27 is a top view of the valve illustrated in FIG. 24; 
     FIG. 28 is a top view of the receptacle disk contemplated for use in the valve illustrated in FIG. 24; 
     FIG. 29 is a top view of an alternative receptacle disk contemplated for use in the valve illustrated in FIG. 24; 
     FIG. 30 is a bottom view of one embodiment of the upper plate contemplate for use in the valve illustrated in FIG. 24; 
     FIG. 31 is a top view of the upper plate illustrated in FIG. 30; 
     FIG. 32 is side view of the upper plate illustrated in FIG. 31; 
     FIG. 33 is a partial cross-sectional view of another embodiment of the filter of the present invention; 
     FIG. 34 is a top view of the filter shown in FIG. 32; 
     FIG. 35 is a cross-sectional illustration of one of the spindles for the filter illustrated in FIG. 33; 
     FIG. 36 is a bottom view illustration of the spindle shown in FIG. 35; 
     FIG. 37 is a side-view illustration of the spindle shown in FIG. 35; 
     FIG. 38 is an enlarged side view of the recess in the spindle shown in FIG. 35; 
     FIG. 39 is a top view of the spindle illustrated in FIG. 35; 
     FIG. 40 is a side-view illustration of the top portion of the filter illustrated in FIG. 33; 
     FIG. 41 is a cross-sectional view of the top portion illustrated in FIG. 40; 
     FIG. 42 is a bottom view of the top portion shown in FIG. 40; 
     FIG. 43 is a top view of the top portion illustrated in FIG. 40; 
     FIG. 44 is an enlarged side view of the inlet of the top portion shown in FIG. 40; 
     FIG. 45 is a side-view of the bottom portion of the filter shown in FIG. 33; 
     FIG. 46 is a bottom view of the bottom portion illustrated in FIG. 45; 
     FIG. 47 is a top view of the bottom portion illustrated in FIG. 45; 
     FIG. 48 is a bottom view of another embodiment of the valve upper plate shown in FIG. 21; 
     FIG. 49 illustrates a top view of the valve upper plate shown in FIG. 48; 
     FIG. 50 shows a top view of another embodiment of the valve according to the present invention, illustrating the position of a relief valve; 
     FIG. 51 is a top view of the sealing member used with the upper plate shown in FIG. 48; 
     FIG. 52 is a top view of another embodiment of the valve of the present invention; 
     FIG. 53 is a side view of the valve illustrated in FIG. 52; 
     FIG. 54 is a cross-sectional side view illustration of the valve depicted in FIG. 52; 
     FIG. 55 is a cross-sectional side view illustration of the valve depicted in FIG. 52, shown along a plane disposed 90 degrees from the cross-sectional view shown in FIG. 54; and 
     FIG. 56 is a bottom view of the valve illustrated in FIG.  52 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 illustrates a filter  10  according to the teachings of the present invention. Filter  10  has an outer, cylindrical casing  12  with a top  14 , a bottom  16 , and a cylindrical tube  18  connected therebetween. The top and bottom are sealingly connected to cylindrical tube  18 . The sealing connection may be either by an adhesive, by welding, by a screw-fit, or by any other suitable connecting means known to those skilled in the art. Cylindrical casing  12  defines an interior volume  20  within which a filter cartridge  22  is disposed. 
     Filter cartridge  22  is a cylindrical structure with an outer support member  24  and an inner support member  26  that sandwich a filter medium  28  therebetween. Inner support member  26  serves to hold filter medium  28  in place when filter  10  is operating. Outer support member  24  serves primarily as a protection of filter medium  28 , especially if filter cartridge  22  is handled during replacement of filter cartridge  22 . This is particularly useful when filter cartridge  22  is a replaceable module. However, as will be described in greater detail below, this is not required to practice the present invention because filter cartridge  22  need not be replaceable. 
     Outer support member  24  also serves to provide indicia  23  of the type of filter medium  28  contained therein. Indicia  23  may also provide other information such as the manufacturer&#39;s name, the size of particles that the filter can remove from the fluid, etc. 
     Filter cartridge  22  has a top end  30  and a bottom end  32 . Filter cartridge  22  has an interior space (not shown) that is essentially a cylindrical volume defined by inner support member  26 . The interior space of filter cartridge  22  is sealed at bottom end  32  by seal  34 . Outer support member  24 , inner support member  26 , and seal  34  all may be made from polypropylene or, alternatively, Acrylonitrile-Butadiene-Styrene (ABS). However, as would be understood by those skilled in the art, any suitable material may be selected depending on the pressure requirements of the system and the corrosive characteristics of the medium that is passed through the filter. 
     As shown in FIG. 2, top end  14  of filter  10  has an inlet port  36  and an outlet port  38 . Top end  30  of filter cartridge  22  sealingly engages outlet port  38 . Accordingly, the fluid medium to be filtered enters filter  10  through inlet port  36 , passes through filter medium  28 , and exits through outlet port  38  in the manner shown by the arrows in FIG.  1 . Naturally, particulate matter is trapped by filter medium  28  as the fluid passes therethrough. 
     In a preferred construction of the present invention, cylindrical casing  12 , top  14 , bottom  16 , cylindrical tube  18 , inlet port  36  and outlet port  38  all may be made of polypropylene or ABS. Each of these elements of filter  10  are preferably sealingly connected to one another or molded together with one another. However, as would be understood by those of ordinary skill in the art, filter  10  may be constructed from any suitable material depending on the medium that is being filtered, the pressure of the medium, and other factors. For example, in caustic or acidic environments, filter  10  may be constructed from Teflon® (tetrafluoroethylene), PTFE, or any equivalent material. Alternatively, inlet port  36  and outlet port  38  need not be made from the same material as cylindrical casing  12 , top  14 , bottom  16 , or cylindrical tube  18 . Instead, inlet port  36  and outlet port  38  may be made of a suitable metal material, such as aluminum or steel (should such a material be required) that is integrated into the construction of top  14  in a manner consistent with techniques known in the art. 
     Filter medium  28  may be made from any substance suitable for the type of filtration required. For example, filter medium  28  may be a hydrophilic spun material. Alternatively, filter medium  28  may be made from Teflon® where the particular environmental circumstances require it. Generally, filter medium  28  is pleated into a cylindrical shape and the free ends of the pleated material are sealed together through a heating process, through ultrasonic vibration welding, or through some other suitable technique known in the art. Regardless of the manner in which the free ends are connected to one another, all that is required is that the free ends of the filter material be sealed to prevent unfiltered fluid from passing through filter medium  28 . 
     As shown in FIG. 2, inlet port  36  includes an inlet flange  40 . Outlet port  38  includes an outlet flange  42 . As shown in both FIGS. 1 and 2 the diameter of inlet flange  40  is smaller than the diameter of outlet flange  42 . As will become more apparent from the discussion that follows, the different diameters of inlet flange  40  and outlet flange  42  prevent the incorrect installation of filter  10  in the valve, which is described in greater detail below. In this manner, the correct orientation of filter  10  in the valve can be assured. 
     FIG. 2 is an end view illustration of filter  10  depicted in FIG.  1 . FIG. 2 shows the difference between the diameters of inlet flange  40  and outlet flange  42 , both of which function as port identifiers. The difference between the port identifiers, in this case the flange diameters, is purposefully created to assure that filter  10  will be properly installed on the filtration system. The smaller inlet flange  40  (or inlet port identifier) is designed to engage a small receiving area on the supply side of the filtration system. Similarly, the larger outlet flange  42  (or outlet port identifier) is designed to engage a larger receiving area on the discharge side of the filtration system. As will become more apparent from the discussion that follows, the different sizes for the flanges prevents outlet port  38  from being connected to the supply side of the filtration system. Similarly, the larger outlet flange  42  prevents outlet port  38  from being inadvertently connected to the discharge side of the filtration system. 
     The constriction of inlet flange  40  and outlet flange  42  shown in FIGS. 1 and 2. however, are not the only flange arrangements possible. As shown in FIGS. 3-8, other arrangements for the port identifiers are possible. For example, as illustrated in FIGS. 3 and 4, it is possible that the sizes of the flanges could be reversed on filter  310  so that inlet flange  340  on inlet port  336  has a larger diameter than outlet flange  342  on outlet port  338 . 
     In still another embodiment of the present invention, the flanges could be altered as illustrated for filter  410  shown in FIGS. 5 and 6. There, the shape of the port identifiers, specifically inlet flange  440  and outlet flange  442 , differ from one another so that inlet port  436  cannot be confused with outlet port  438 . It should be noted that, while inlet flange  440  is shown with a triangular shape and outlet flange  442  is shown with a square shape, those skilled in the art will readily appreciate that any of an infinite variety of shape arrangements are possible so long as inlet port  436  may be differentiated from outlet  438 . 
     As shown in still another embodiment of the present invention, the outer diameters of the inlet and outlet ports themselves could be altered instead of the flanges to achieve the same objective. Specifically, as illustrated for filter  510 , the outer diameter of inlet port  536  could be modified so that it is larger than the outside diameter of nozzle end  539 . This arrangement is depicted in FIGS. 7 and 8. As shown, the outside diameter of nozzle end  537  has been increased in size so that it is coextensive with flange  540 . A similar modification could also be made to nozzle end  539 , as would be understood by those skilled in the art. As with the other embodiments, the purpose of increasing the outside diameter of nozzle end  537  or nozzle end  539  is to create a distinction between inlet port  536  and outlet port  538  so that filter  510  cannot be improperly installed on the filtration system. 
     FIG. 9 illustrates a cross-sectional view of a first embodiment of a valve  44  designed to operate in connection with filter  10  illustrated in FIGS. 1 and 2. FIG. 10 illustrates a bottom view of valve  44  and shows the cross-section line (line  9 — 9 ) through which FIG. 9 is taken. FIG. 11 shows another cross-section of valve  44  taken along a line shifted 90° from the cross-section line in FIG.  9 . FIG. 12 illustrates valve  44  from a top view. 
     Valve  44  is made with an upper plate  46 , a receptacle disk  48 , and a lower plate  50 . Upper plate  46  is connected to receptacle disk  48  through a shaft  52  so that receptacle disk  48  can rotate in relation to upper plate  46 . Shaft  52  can be a screw or other suitable connector. Shaft  52  is connected to receptacle disk  48  and passes through upper plate  46 , as shown. In the embodiment illustrated, shaft  52  is held in place by a nut or lock nut  53  (or, alternatively, several bolts). Nut  53  permits the pressure between upper plate  46  and receptacle disk  48  to be adjusted so that receptacle disk  48  may rotate freely with respect to upper plate  46  (as will be explained in greater detail below). In addition, nut  53  assures that sufficient pressure will be applied between upper plate  46  and receptacle disk  48  so that fluid does not leak from between the upper plate  46  and receptacle disk  48  when valve  44  is in use. Also, the arrangement of shaft  52  and nut  53  facilitates disassembly of valve  44  so that the individual parts may be serviced or so that o-rings that have become worn may be replaced. 
     As would be appreciated by those skilled in the art, there are many alternatives to the arrangement of shaft  52  and nut  53  that may be used without departing from the scope and spirit of the present invention. Moreover, as will also be appreciated by those skilled in the art, connectors other than shaft  52  and nut  53  also could be substituted without departing from the scope of the present invention. 
     Upper plate  46 , which is shown in this first embodiment as a rectangularly-shaped element of valve  44 , is connected to lower plate  50  through rigid members  54  such as screws. It should be appreciated, however, that rigid members  54  need not be screws. All that is required for the embodiment described is that upper plate  46  and lower plate  50  be rigidly connected to one another so that they cannot rotate with respect to one another. 
     Upper plate  46  is connected to the fluid supply and discharge lines (not shown). As illustrated in FIG. 11, therefore, upper plate  46  includes a fluid inlet port  56  and a fluid outlet port  58 . Fluid inlet port  56  and fluid outlet port  58  are elbow-shaped bores that extend through upper plate  46  and extend to receptacle disk  48 . While elbow-shaped bores are illustrated, it should be understood that this particular arrangement is not required by the present invention. Other arrangements, such as the ones illustrated in FIGS. 30-31 and FIGS. 52-56, may be substituted while remaining within the scope of the teachings of the present invention. 
     Receptacle disk  48  is a cylindrically-shaped structure that includes a fluid inlet port  60  and a fluid outlet port  62  with cross-sections that allow filter inlet port  36  and filter outlet port  38  to mate easily therewith. Specifically, fluid inlet port  60  is shaped so that it readily accepts the configuration of the port identifier associated with filter inlet port  36 . Similarly, fluid outlet port  62  is configured so that it readily accepts the configuration of the port identifier associated with filter outlet port  38 . In other words, the configuration of fluid inlet port  60  and fluid outlet port  62  is such that filter  10  will be correctly installed in every instance, because only one orientation of filter  10  to valve  44  is possible. 
     Lower plate  50  acts to restrain filter  10  when inserted into valve  44 . Lower plate  50  is a circularly-shaped plate with a cammed opening  64  cut therethrough, as shown in FIG. 10. A pin  66  extends from receptacle disk  48  into the cammed opening  64  in lower plate  50 . Pin  66  acts as a security stop for valve  44  to prevent over-rotation of receptacle disk  48 . 
     The operation of valve  44  will now be explained with respect to FIGS. 1-2 and  9 - 12 . When inlet port  36  and outlet port  38  of filter  10  are inserted into fluid inlet port  60  and fluid outlet port  62  in receptacle disk  48 , receptacle disk  48  is positioned so that it does not communicate with fluid inlet  56  or fluid outlet port  58 . In other words, when filter  10  is inserted into valve  44 , valve  44  is in an “off” position. The “off” position is illustrated in FIGS. 9 and 11. Once filter  10  has been positioned in valve  44 , filter  10  and receptacle plate  48  are rotated 90 degrees. After rotation, fluid inlet port  56  aligned with filter inlet port  36  and fluid outlet port  58  is aligned with filter outlet port  38  so that fluid may flow through filter  10 . Valve  44 , therefore, acts as a gate valve to turn on or off the flow to filter  10 , which facilitates the removal and replacement of filter  10  and permits a rapid exchange of the filter without spillage of the medium to be filtered. 
     As will be explained in greater detail, lower plate  50  facilitates the filter exchange operation. Cammed opening  64  has an inlet portion  68  and an outlet portion  70  that are large enough to permit inlet flange  40  and outlet flange  42  to pass therethrough. However, when receptacle disk  48  is turned 90 degrees, cammed opening  64  provides an inlet retention surface  72  and an outlet retention surface  74  that are not spaced as far from the center of lower plate  50  as inlet portion  68  and outlet portion  70 . In other words, inlet retention surface  72  and outlet retention surface  74  extend inwardly toward the center of lower plate  50  As a result, when filter  10  is rotated with receptacle disk  48 , retention surface  72  prevents outlet flange  42  from disengaging receptacle disk  48  because it holds outlet port  38  in receptacle disk  48  by providing a barrier that contacts with a lower surface  37  of inlet port  36  (see FIG.  1 ). Similarly, retention surface  74  prevents inlet port  36  from disengaging from receptacle disk  48  because it acts as a barrier to the movement of inlet flange  40  out of fluid inlet port  60 . Specifically, upon rotation of receptacle disk  48  so that the valve is in the “on” position, retention surface  74  engages a lower surface  39  of outlet flange  38  (see FIG.  1 ). 
     Pin  66  abuts pin stop  76  on cammed opening  64  when receptacle disk  48  has been rotate so that valve  44  is closed and filter  10  can be removed from valve  44 . Pin  66  acts as a safety feature to prevent the inadvertent over-rotation of receptacle disk  48  when there is no filter  10  in valve  44  to assure that fluid inlet port  56  will align with filter inlet port  36  and that fluid outlet port  58  will align with filter outlet port  38 . This prevents filter inlet port  36  and filter outlet port  38  from becoming reversed. 
     Upper plate  46  and receptacle disk  48  may be made from any suitable material. For example, aluminum may be used for both structures and is preferred for its low weight and strength. Stainless steel may also be used where the particular application requires it. However, stainless steel is considerably heavier than aluminum and more expensive. Alternatively, it is possible that the various components of valve  44  could be constructed from a plastic material such as polypropylene or ABS, as would be under stood by those skilled in the art. Regardless of the materials used for the construction of upper plate  46  and receptacle disk  48 , lower plate  50 , while it may also be fashioned from aluminum or steel, is preferably made from polypropylene or ABS (or other suitable polymeric or plastic material). 
     To create a fluid-tight seal between upper plate  46  and receptacle disk  48 , upper plate  46  is provided with a number of grooves  78  in which o-rings  80  may be positioned, as shown in FIGS. 9 and 11. A more detailed illustration of the arrangement of o-rings  80  is shown throughout the various figures of the drawings, as will be explained in greater detail below. While the first embodiment of receptacle disk  48  has been described in connection with the first embodiment of filter  10  of the present invention, those of ordinary skill in the art will readily recognize that receptacle disk  48  may be modified to accommodate the other embodiments of filter  10  that are illustrated in FIGS. 3-8. In each case, the receptacle disk for the valve may be altered so that the particular valve embodiment may accept the inlet ports and outlet port identifiers associated with the respective inlets and outlets for the filter. 
     For example, FIGS. 13-14 illustrate valve  344  that is designed to accommodate filter  310  illustrated in FIGS. 3-4. There, outlet flange  342  has a smaller diameter than inlet flange  340 . As a result, filter inlet port  360  and filter outlet port  362  on receptacle disk  348  must be adapted to accommodate them. Accordingly, in this embodiment, inlet port  360  has a larger diameter to accommodate the larger diameter of inlet flange  340 . Similarly, outlet port  362  has a smaller diameter than inlet port  360  to accommodate the smaller diameter of outlet flange  342 . In addition, inlet retention surface  372  and outlet retention surface  370  are altered in valve  344  to accommodate this change in the design. 
     FIGS. 15-16 illustrate valve  444 , which is constructed according to the third embodiment of the present invention. Here, valve  444  is designed to receive filter  410 , which is illustrated in FIGS. 5-6. As described above, inlet flange  440  has a triangular shape while outlet flange  442  has a rectangular shape. To receive these port identifiers, receptacle disk  448  includes filter inlet port  460  and filter outlet port  462  that are shaped t o accommodate inlet flange  440  and outlet flange  442 . In addition, lower plate  450  includes a cammed of opening  464  with an inlet portion  68  and an outlet portion  470  that is also shaped to accommodate inlet flange  440  and outlet flange  442 . The inlet portion defines an inlet retention surface  472  and the outlet portion defines an outlet retention surface  474  that operate as described above to keep filter  410  in fluid communication with filter inlet port  460  and filter outlet port  464 . 
     FIGS. 17-18 show valve  544 . Valve  544  is designed to accommodate filter  510  that is illustrated in FIGS. 7 and 8. To do so, receptacle disk  548  contains a filter inlet port  560  that can accommodate the shape of the port identifier associated with filter inlet  536 . Filter outlet port  562  is shaped to accommodate the port identifier associated with filter outlet  538 . The operation of filter  510  is the same as with the previously described embodiments. 
     In addition to these embodiments and consistent with the teachings herein, it should be appreciated that any particular arrangement of the port identifiers may be selected from the embodiments described above. Moreover, as those skilled in the art would readily recognize, there are many other constructions possible for the port identifiers that also fall within the scope of the present invention. 
     FIG. 19 illustrates a bottom view of receptacle disk  48 , showing in greater detail fluid inlet port  60  and fluid outlet port  62 . Pin  66  is also illustrated in this figure, as is the location of shaft  52 . FIG. 20, which is a cross-section of receptacle disk  48  taken along the cross-section line  20 — 20  in FIG. 19, illustrates receptacle disk  48  in greater detail as well. 
     FIG. 21 illustrates upper plate  46  from a bottom view. As shown, upper plate  46  includes a large o-ring groove  82  that surrounds the hole for the shaft  52 . It should be noted, however, that large o-ring groove  82  need not be concentric with the hole for shaft  52 , even though this is the arrangement shown in FIG.  21 . It should be noted that the particular o-ring arrangement is not necessary to practice the present invention. As will be made more clear from the description that follows, many o-ring arrangements are possible as would be understood by those skilled in the art. 
     As illustrated in FIG. 21, large o-ring groove  82  encircles fluid inlet port  60  and fluid outlet port  62 . An inlet port o-ring groove  84  surrounds fluid inlet port  60 . An outlet port o-ring groove  86  surrounds fluid outlet port  62 . A shaft o-ring groove  88  surrounds the hole in receptacle plate  46  for shaft  52 . When valve  44  is assembled, each of the grooves holds an o-ring  80  to seal fluid inlet port  60  and fluid outlet port  62  from one another and from the environment. O-rings  80  prevent discharge of the fluid being filtered during the filtration operation and also during rotation of receptacle plate  46  when valve  44  is opened and closed. 
     FIG. 22 illustrates another embodiment of the filter according to the present invention. In FIG. 22, filter  100  is shown with a less angular appearance, both externally and internally. Also, filter  100  is shown with a slightly larger overall size than filter  10 . As shown, top  114  and bottom  116  have a curved appearance, both externally and internally. As with filter  10 , filter  100  includes an inlet port  36  and an outlet port  38 . Fluid flows into the inlet port  36 , through filter cartridge  22 , and exits through outlet port  38 . An interior volume  120  is defined between cylindrical tube  118  of cylindrical housing  112  and filter cartridge  22 . In most other respects, filter  100  is like filter  10 . The operation of filter  100  does not differ significantly from filter  10 . Moreover, while flanges  40 ,  42  are illustrated, any combination of port identifiers may be applied to filter  100  in the same manner as described in relation to filter  10 . 
     As shown in FIGS. 33 and 34, which illustrate still another embodiment of the filter of the present invention, filter  200  is preferably a unitary, sealed construction so that filter  200  may be conveniently disposed. While it is preferred that filter  200  be disposable, filter  200  may be constructed so that cartridge  222  may be removed from the interior thereof and removed. 
     While similar in many respects to the other embodiments disclosed, filter  200  is provided with a two-part construction, a top portion  214  and a bottom portion  216 . Both portions are preferably constructed from ABS (Acrylonitrile-Butadiene-Styrene) (although any suitable plastic or polymeric material may be used). Top portion  214  may threadedly engage  216 , it may be mechanically welded to bottom portion  216  (e.g., by an adhesive), or it may be chemically welded to bottom portion  216 , depending on whether or not top and bottom portions  214  and  216  are to be reused after filter cartridge  222  is changed. To form a sealable engagement, top portion  214  extends over a portion of bottom portion  216 . 
     Top portion  214  is provided with an inlet port  236  and an outlet port  238 . Fluid flows into filter  200  through inlet  236 , passes through filter cartridge  222  and exits from filter  200  through outlet  238 . An interior volume  220  is defined between cylindrical tube  218  of cylindrical housing  212  and filter cartridge  222 . The operation of filter  200  is the same as for filter  10  and filter  100 . Flanges  240  and  242  operate in the same manner as flanges  40 ,  42  in the other embodiment described. 
     Filter  200  differs from filters  10  and  100  in that it further includes spindles  211  and  213 , the construction of which are illustrated in greater detail (typically) in FIGS. 35-39. While spindle  211  is illustrated in FIGS. 35-39, it should be noted that the same construction applies equally to spindle  213 . Spindle  211  includes a forward necked-down region  215  connected to a wider, base portion  217 . A recess  219  is provided between necked-down region  215  and base portion  217  to accommodate an o-ring  221  (see FIGS.  33  and  38 ). As shown in FIG. 33, spindle  211  is sealingly attached to top portion  214  on its interior through a connection between base portion  217  of spindle  211  and a cylindrical wall portion  231  that may be integrally molded to the interior surface of top portion  214 . Necked-down region  215  is inserted into the interior of cartridge  222  and o-ring  221  forms a sealing engagement with the interior of cartridge  222  so that fluid cannot enter the interior of cartridge  222  without passing through cartridge  222  in the intended manner. The same is true for spindle  213 , except that spindle  213  sealingly engages the base of bottom portion  216  by fitting onto an indented portion  233  that projects into the bottom of filter  200 . 
     ABS is the preferred material from which filter  200  is constructed because top portion  214  and bottom portion  216  may be easily and sealingly connected to one another with a sealant/adhesive that is known to those skilled in the ABS art. It should be noted, however, that filter  200  could be constructed from polypropylene or any other suitable material. As shown, top portion  214  slides onto a insert portion  237  of bottom portion  216  until bottom portion abuts stops  235  that may be integrally formed with the interior surface of top portion  214 . 
     FIGS. 40-44 illustrate the construction of top portion  214  in greater detail. 
     FIGS. 45-47 illustrate the construction of bottom portion  216  in greater detail. 
     FIGS. 24-31 illustrate alternate embodiments of valve  44  discussed in detail above. To avoid repetition, primarily only the differences from the components illustrated in valve  44  are discussed in detail below. 
     As shown in FIG. 24, valve  144  includes an upper plate  146 , a receptacle disk  148 , and a lower plate  150 . However, in valve  144 , there are differences in each of these structures that distinguish them from upper plate  46 , receptacle disk  48  and lower plate  50  in valve  44 . 
     For example, as illustrated in FIG. 25, which is a bottom view of valve  144 , and as illustrated in FIG. 27, which is a top view of valve  144 , upper plate  144  is cylindrically-shaped rather than being rectangularly-shaped. In addition, inlet port  156  and outlet port  158  extend radially within upper plate  146 . As illustrated in FIG. 26, inlet port  156  may have tapered inner sides  157  and outlet port  158  may have tapered inner sides  159 . Alternately, inner sides  157 ,  159  may not be tapered at all or may have a greater degree of taper than shown, depending on the design requirements. 
     Screws  154  are placed in different locations in valve  144  than they are in valve  44 . Specifically, one of screws  154 , screw  155 , is offset from the periphery of upper plate  146  so that it intersects with a portion  157  of receptacle plate  148  that has been removed. The interaction of screw  155  and portion  157  provides a limit barrier beyond which receptacle plate  148  cannot be turned. This prevents receptacle plate  148  from being turned so that the fluid lines  156  and  158  and the fluid inlet port  160  and fluid outlet port  162  do not become improperly aligned. In other words, screw  155  provides the same function as pin  66  in valve  44 . 
     Instead of providing a single opening in lower plate  150  (as was done in lower plate  50 ), cammed surface  164  in lower plate  150  is divided into two separate cammed surfaces, inlet cammed surface  161  and outlet cammed surface  163 . While lower plate  150  differs from lower plate  50  because it does not include a single cammed opening  64 , cammed surfaces  161 ,  163  act in the same manner as cammed opening  64 . Specifically, cammed surfaces  161 ,  163  are shaped to engage lower surfaces  37 ,  39  of inlet port  36  and outlet port  38  so that filter  100  is retained by valve  144  during operation. 
     As illustrated in FIGS. 24,  26 ,  28 ,  29 , and  30 , the placement of the o-ring grooves also differs in valve  144  from valve  44 , but all are consistent with a two (or more) piece seal construction. However, in keeping with the teachings of the present invention, any of the o-ring configurations described herein can be used on any of the valve embodiments that fall within the scope of the present invention. This includes the one piece molded seal described in greater detail below. 
     As illustrated in FIG. 28, an o-ring groove  179  encircles fluid inlet port  160  for placement of an o-ring therein. A second, kidney-shaped o-ring groove  181  is placed around o-ring groove  179 . Kidney-shaped bring groove  181  extends to a location 90 degrees from fluid inlet port  160 , which is the location of the inlet port in upper plate  146  when upper plate  146  and receptacle disk  148  are not aligned so that fluid flows to the filter cartridge. Fluid output port  162  also has a circular o-ring groove  183  therearound. A kidney-shaped o-ring groove  185  extends around the circular o-ring groove  183  and encompasses. The location on receptacle disk  148  where fluid outlet  158  will be located when valve  144  is in the “off” position. When kidney-shaped o-ring grooves  181 ,  185  contain o-rings, therefore, they act as a seal to prevent the leakage of fluid from the fluid supply and discharge lines when valve  144  is in the “off” position. 
     FIG. 29 illustrates an alternate embodiment of receptacle disk  248 , which does not include removed portion  157 . As a result, receptacle disk  248  might include a pin (like pin  66  (not shown)) to prevent the over-rotation of receptacle disk  248  during replacement of the filter. Alternately, receptacle disk  248  could be manufactured to include a removed portion  157  as illustrated in FIGS. 25-27. 
     As illustrated in FIG. 29, receptacle disk  248  contains an o-ring groove configuration that differs from the configuration illustrated in FIG.  28 . As illustrated, a first o-ring groove  281  encircles the opening to fluid inlet port  260  and a second o-ring groove  283  encircles the opening of fluid outlet port  262 . A third o-ring groove  285  encircles both o-ring groove  281  and o-ring groove  283  by encircling the periphery of receptacle disk  248 . A fourth o-ring groove  287  may be included in receptacle disk  248 . When each of these grooves contain o-rings, they prevent the leakage of fluid from the valve when it is operating. When an o-ring is placed into fourth o-ring groove  287 , fluid is prevented from flowing into the hole for shaft  252 . 
     Regardless of the o-ring placement in the receptacle disk, o-rings also may be provided on the bottom surface of upper plate  246 . As illustrated, a first o-ring groove  277  may be positioned to encircle fluid inlet port  260  while a second o-ring groove  279  may be positioned to encircle fluid outlet port  262 . O-rings placed into these grooves assist in sealing the engagement between upper plate  246  and receptacle disk  248  so that fluid does not leak from between the two valve parts. 
     FIGS. 31 and 32 illustrate another embodiment of upper plate  247  that is contemplated by the present invention. In this embodiment, fluid inlet port  261  and fluid outlet port  263  extend through upper plate  246  without changing direction. Moreover, inner sides  201 ,  203  of fluid inlet port  261  and fluid outlet port  263  are tapered. 
     While not shown, filter  200  also may include a pressure relief valve on top portion  214  or bottom portion  216  (or even on the valve itself or the fluid lines connected thereto) to release pressure in filter  200  before filter  200  is removed from its associated valve. Because filter  200  is made from an expansible material (such as ABS), it tends to expand when connected to the liquid to be filtered. As a result, when the pressure of the fluid is sufficiently great, if filter  200  is removed from the valve without first releasing the pressure therein, a stream of fluid may eject from inlet port  236  and outlet port  238 . To avoid the sudden release of fluid in a sterile environment (such as in a clean room or in a surgical operating room), the relief valve is operated before filter  200  is removed from the valve. The pressure relief valve may also assist in situations where a negative pressure (or a suction force) inhibits removal of filter  200  from its associated valve. 
     FIGS. 49-50 illustrate the placement of one embodiment of a relief valve  389  in upper plate  347 . Relief valve  389  is a hole drilled into upper plate  347  to release the pressure in the system when the valve has been turned to the off position and the filter is to be removed therefrom. While the relief valve  389  is shown as a hole, those skilled in the art will readily recognize that there are many suitable alternatives. 
     FIG. 48 illustrates an alternate embodiment of the upper plate shown in FIG.  21 . In FIG. 48, however, upper plate  347  includes a recess  390  that accommodates a unitary, kidney-shaped sealing member  391 , which is shown in greater detail in FIG.  51 . Sealing member  391  includes a first circular section  392  and a second circular section  393  that are joined to one another by a first connecting portion  394  and a second connecting portion  395 . Sealing member  391  acts to seal upper plate  347  against the lower plate to prevent the leakage of fluid when the valve is turned from the opened to the closed positions. Sealing member  391  acts in the same manner as o-rings  179 ,  181 ,  183 , and  185 , which are illustrated in the embodiment shown in FIG.  28 . 
     FIGS. 52-56 illustrate one further embodiment of the valve according to the teachings of the present invention. Valve  644  includes an upper plate  646 , a receptacle disk  648 , and a lower disk  650 . As with other embodiments of the valve, upper plate  646  is connected rotatably to receptacle disk  648  by a shaft  652  so that receptacle disk  648  can rotate in relation to upper plate  646 . Shaft  652  can be a screw or other suitable connector. Shaft  652  is connected to receptacle disk  648  and extends through upper plate  646  as shown. As illustrated, shaft  652  is held in place be a nut or lock nut  653  (or, alternatively, several nuts or bolts, as shown). Nut  653  permits the pressure between upper plate  646  and receptacle disk  648  to be adjusted so that receptacle disk  648  may freely rotate with respect to upper plate  646 . In addition, nut  653  assures an appropriate relationship between upper plate  646  and receptacle disk  648  so that the fluid ports on the filter align appropriately with the inlet and discharge lines from the fluid system to which valve  644  is attached. 
     Upper plate  646 , in the embodiment shown, is a circular plate that is rigidly connected to lower plate  650  by several rigid members  654 , such as screws. It should be appreciated, however, that rigid members  654  need not be screws. All that is required for this embodiment is that upper plate  646  and lower plate  650  be rigidly connected to one another so that they cannot rotate with respect to one another. 
     Cylindrical wall  649  is connected to both the fluid supply and discharge lines (not shown). As shown in FIG. 55, fluid inlet port  660  is connected fluidly to a fluid inlet port  656 , which is shown as an elbow-shaped passage through receptacle disk  648 . Similarly, fluid outlet port  662  is connected fluidly to a fluid outlet port  658 , which is shown as an elbow-shaped passage through receptacle disk  648 . Fluid inlet port  656  is connected fluidly to cylindrical wall inlet  657  that connects to the fluid supply line in a conventional manner (not shown). Fluid outlet port  658  is connected fluidly to cylindrical wall outlet port  659  that connects to the fluid discharge line in a conventional manner (not shown). 
     Cylindrical wall  649  is connected to both the fluid supply and discharge lines (not shown). As shown in FIG. 55, filter inlet port  660  is connected fluidly to a fluid inlet  656 , which is shown as an elbow-shaped passage through receptacle disk  648 . Similarly, filter outlet port  662  is connected fluidly to a fluid outlet  658 , which is shown as an elbow-shaped passage through receptacle disk  648 . Fluid inlet  656  is connected fluidly to cylindrical wall inlet  657  that connects to the fluid supply line in a conventional manner (not shown). Fluid outlet  658  is connected fluidly to cylindrical wall outlet  659  that connects to the fluid discharge line in a conventional manner (not shown). 
     Receptacle disk  548  is a cylindrically-shaped structure where the fluid inlet port  660  is configured to readily accept the configuration of the port identifier associated with the inlet port  36 , for example. Similarly, fluid outlet port  662  is configured so that it readily accepts the configuration of the port identifier associated with filter outlet port  38 . The configuration of fluid inlet port  660  and fluid outlet port  662  are such that filter  10 , for example, will be correctly installed in every instance, It should be appreciated, however, that fluid inlet port  660  and fluid outlet port  662  may be configured to accept any of the configurations of the port identifiers that fall within the scope of the present invention. 
     Like lower plate  50 , lower plate  650  acts to restrain filter  10  when inserted into valve  644 . Lower plate  650  is circularly-shaped with a cammed opening  664  therethrough. A pin  666  extends from receptacle disk  648  into cammed opening  664  to act as a security stop for valve  644  to prevent over-rotation of receptacle disk  648 . 
     The operation of valve  644  is very similar to that of valve  44 , despite the differences therebetween. When inlet port  36  and outlet port  38  are inserted into fluid inlet port  660  and fluid outlet  662 , receptacle disk  648  is positioned so that fluid inlet  656  does not align with circular wall inlet  657 . Similarly, fluid outlet  658  is not aligned with circular wall outlet  659 . This is the “off” position of valve  64 . 
     Cammed opening  664  has an inlet portion  668  and an outlet portion  670  that are shaped to permit inlet flange  40  and outlet flange  42  to pass therethrough so that filter  10  can be inserted into or removed from valve  644 . However, when receptacle disk  648  is turned  90  degrees to the “on” position, cammed opening  664  provides an inlet retention surface  672  and an outlet retention surface  674  that are not spaced as far from the center of lower plate  650  as inlet portion  668  and outlet portion  670 . As a result, inlet retention surface  672  and outlet retention surface  674  prevent filter  10  from becoming dislodged from valve  644  during operation. As with valve  44 , pin  666  abuts pin stop  676  when valve  644  is in the “off” position to prevent the over-rotation of receptacle disk  648  (and, consequently, to prevent the inlet and outlet ports from becoming misaligned with the supply and discharge lines of the filtration system.) 
     As described in connection with valve  44 , upper plate  646  and receptacle disk  648  may be constructed from any suitable material such as aluminum or steel. Alternatively, they may be made from a suitable plastic or polymeric material such as polypropylene or ABS. Regardless of the material used for the construction of upper plate  646  and receptacle disk  648 , it is preferred that lower disk  650  be made from polypropylene or ABS (or any other suitable plastic or polymeric material). 
     To provide a fluid-tight seal between receptacle disk  648  and cylindrical wall  649 , o-rings  680 ,  682  are provided. O-rings  680  surround both fluid inlet  656  and fluid outlet  658 . For superior fluidic sealing, second o-rings  682  are disposed around o-rings  680 . As would be understood by those skilled in the art, however, any alternative arrangement of o-rings or seals may be used so long as valve  644  is prevented from leaking during operation. 
     As should be appreciated by those skilled in the art, the embodiments described above are not meant to limit the scope of the present invention. They are meant to be exemplary of the many embodiments and variations that are encompassed herein and that are claimed below.