Abstract:
Fluid separation assembly that allows easy and fast change-out even in confined spaces, and also minimizes or eliminates leakage during change-out. A fluid separation unit having a housing containing separation means, the housing having an inlet and an outlet spaced from the inlet, each including a fitting for attachment of the housing to a manifold or other device allowing fluid communication through the separation means to a point of use is provided. The fittings are designed for quick connect/disconnect, and for minimal or no leakage. The fittings may be on opposite ends, with top and bottom fittings of different configurations, thereby ensuring proper installation of the assembly. The particular medium to be separated is not particularly limited, and can include slurries, fluids including water, and pre-loaded chromatography columns.

Description:
[0001]     This application is a Divisional of U.S. patent application Ser. No. 10/647,609 filed on Aug. 25, 2003, which is a Divisional of U.S. patent application Ser. No. 09/796,038 filed on Feb. 28, 2001 (now U.S. Pat. No. 6,652,749 issued Nov. 25, 2003), which claims priority of U.S. Provisional Application No. 60/185,991 filed on Mar. 1, 2000, the disclosures of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     Fluid separation units with fittings may be installed in small spaces that make it very difficult to change out the filter unit. For example, it can be difficult to turn a fitting during installation and removal in a confined space. Even a quick disconnect fitting can be awkward and difficult to manipulate in the spaces typical in industrial filtration applications. Conventional fittings require that there be sufficient space to allow the operator&#39;s hands to manipulate the fitting. In addition, there is generally excess tubing, which allows the fittings or quick disconnects to be removed. There also may be additional tubing present to allow the filter unit to be removed from its installed position to a location with room enough that the fittings/quick disconnects can be removed easily. However, moving tubing around is very undesirable because tubing can be easily damaged, and contamination adhering to the inside surface of tubing walls may be dislodged into the fluid. Conventional disposable filters are also time consuming to change due to cumbersome fittings. Also, filters often require extra space above and/or below to allow vertical movement for removal, and space is a premium.  
         [0003]     Another problem associated with conventional disposable fluid separation devices is leakage during change-out. Since the chemicals used in a particular process may be hazardous, any leakage is undesirable, both from an environmental standpoint and in terms of operator safety. Similarly, tubing associated with the device can leak or drip during change-out, also potentially resulting in a hazardous condition.  
         [0004]     It is therefore an object of the present invention to provide a removable fluid separation assembly that can be installed in a confined space and readily connected and disconnected.  
         [0005]     It is a further object of the present invention to provide a removable separation assembly that includes fittings that allow installation with one easy motion and do not require that each fitting be individually connected.  
         [0006]     It is yet a further object of the present invention to provide a separation assembly that includes dripless connections, preventing leakage during change-out.  
         [0007]     It is still another object of the present invention to provide a separation assembly that minimizes or eliminates air entrapment during change-out.  
         [0008]     It is a still further object of the present invention to provide a separation assembly with oriented connection, preventing incorrect installation of the assembly.  
       SUMMARY OF THE INVENTION  
       [0009]     The problems of the prior art have been overcome by the present invention, which provides a fluid separation assembly that allows easy and fast change-out even in confined spaces, and also minimizes or eliminates leakage during change-out. According to a preferred embodiment of the present invention, a fluid separation unit having a housing containing separation means, the housing having a first end and a second end spaced from the first end, each of said first and second ends including a fitting for attachment of the housing to a manifold or other device allowing fluid communication through the separation means to a point of use is provided. The fittings are designed for quick connect/disconnect, and for minimal or no leakage. The top and bottom fittings may be of different configurations, thereby ensuring proper installation of the assembly. The particular medium to be separated is not particularly limited, and can include slurries, fluids including water, and pre-loaded chromatography columns. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a cross-sectional representation of a separation unit in accordance with a first embodiment of the present invention;  
         [0011]      FIG. 2  is a cross-sectional view of a valve for a separation unit in accordance with one embodiment of the present invention;  
         [0012]      FIG. 2   a  is a cross-sectional view of a portion of the valve of  FIG. 1 ;  
         [0013]      FIG. 3  is a cross-sectional view of a portion of the valve of  FIG. 2 ;  
         [0014]      FIG. 4  is a cross-sectional representation of a valve for a separation unit in accordance with another embodiment of the present invention;  
         [0015]      FIG. 4   a  is a cross-sectional view of a portion of the valve of  FIG. 4 ;  
         [0016]      FIG. 4   b  is a cross-sectional view of another embodiment of the valve of  FIG. 4 ;  
         [0017]      FIG. 5  is a cross-sectional representation of a separation unit in accordance with another embodiment of the present invention;  
         [0018]      FIG. 5   a  is a cross-sectional view of the upper fitting of the valve of  FIG. 5 ;  
         [0019]      FIG. 5   b  is a cross-sectional view of the lower fitting of the valve of  FIG. 5 ;  
         [0020]      FIG. 6  is a cross-sectional representation of a separation unit in accordance with yet another embodiment of the present invention;  
         [0021]      FIG. 7  is a cross-sectional side view of a separation unit in accordance with still another embodiment of the present invention;  
         [0022]      FIG. 7   a  is a front view of the separation unit of  FIG. 7 ;  
         [0023]      FIG. 8  is a cross-sectional side view of a separation unit in accordance with another embodiment of the present invention, shown being installed in the manifold;  
         [0024]      FIG. 8   a  is a cross-sectional side view of the separation unit of  FIG. 8  shown in the installed position;  
         [0025]      FIG. 8   b  is a cross-sectional top view of the unit of  FIG. 8  shown in the installed position;  
         [0026]      FIGS. 8   c ,  8   d  and  8   e  are cross-sectional views of further embodiments of the fitting in accordance with the present invention;  
         [0027]      FIG. 8   f  is a cross-sectional view of a prior art fitting;  
         [0028]      FIG. 9  is a schematic representation of a separation system in accordance with an embodiment of the present invention;  
         [0029]      FIG. 10  is a cross-sectional side view of a separation unit being installed in a further embodiment of the present invention;  
         [0030]      FIG. 10   a  is a side view of the unit of  FIG. 10  in an installed position;  
         [0031]      FIG. 10   b  and  10   c  are enlarged view of the latch mechanism of  FIG. 10 ;  
         [0032]      FIG. 10   d  is a cross-sectional view of a separation unit being installed in a further embodiment of the present invention;  
         [0033]      FIG. 10   e  is a side view of the unit of  FIG. 10   d  in an installed position;  
         [0034]      FIG. 11  is a cross-sectional side view of a separation unit being installed in a still further embodiment of the present invention;  
         [0035]      FIG. 11   a  is a cross-sectional side view of the separation unit of  FIG. 11  in an installed position;  
         [0036]      FIG. 12  is a cross-sectional side view of an installed separation unit in accordance with another embodiment of the present invention; and  
         [0037]      FIG. 13  is a cross-sectional side view of yet another embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0038]      FIG. 9  shows a schematic of a typical fluid separation system in which the present invention may be applied. Those skilled in the art will appreciate that the separation systems of the present invention include filters, purifiers, concentrators and contactors (e.g., degassers and ozonators). For purposes of illustration, the separtions systems will be exemplified by filters, although the present invention is not limited thereto. A filter  12  is shown having an inlet end  90  and an outlet end  100  (these could be reversed), each for respective connection to lower and upper manifolds  16 ,  14 . A nitrogen/clean dry air line is used to purge the filter  12 . A deionized water (DI) line is used to flush the filter  12 . Suitable preferably air-actuated valves V 1 -V 6  are appropriately positioned as shown. For filter change-out, the manual shut-off valve  150  on the inlet line is closed, and the filter  12  is purged with nitrogen or clean dry air. The filter  12  is then flushed with DI water, purged again with nitrogen or clean dry air, and the filter  12  is removed from the manifolds and replaced. For start-up, after the new filter is installed, it is flushed with DI water, purged, and the manual shut-off valve  150  is opened. The filter  12  is primed with the fluid of choice and ready for use. It will be understood by those skilled in the art that the foregoing procedure is illustrative only; other start-up and change-out procedures could be used with the filter assembly of the present invention.  
         [0039]     Turning now to  FIG. 1 , there is shown a manifold  10  housing one or more separation units, which in the embodiment shown, are filter units  12  (two shown). Each filter unit  12  is adapted to be connected to a top manifold  14  and a bottom manifold  16 . Those skilled in the art will appreciate that although manifolds are illustrated, other means for attaching each filter unit to the system and providing fluid communication into and out of the filter units can be used. For convenience, however, the ensuing description will refer to manifolds. Preferably the manifolds are independent, which will allow for separate changing of each filter unit  12 . One or more of the manifolds may include pressure transducers (not shown) or other sensors for monitoring the conditions of the process. The filter units  12  may include one or more guide blocks  18  to facilitate mounting of the units in a module.  
         [0040]     The filter units  12  may be completely disposable, or may comprise a reusable housing having a disposable inner cartridge. In the embodiment shown in  FIG. 1 , the first (top) end of each filter unit  12  has a male fitting or coupling  20 , preferably centrally located (with respect to the housing of said filter  12 ) and preferably cylindrical, for attachment to upper manifold  14 . Similarly, the second (bottom) end of each filter unit  12 , which is spaced from and preferably opposing the first end, has a fitting or coupling  21 , also preferably centrally located, for attachment to receiver  22  on lower manifold  16 . At least one of the manifolds  14 ,  16  is movable between a first disengaged position, shown as the left-hand manifold  14  in  FIG. 1 , to a second engaged position, shown as the right-hand manifold  14  in  FIG. 1 . In the first disengaged position, receiver  19  on manifold  14  is disengaged from the coupling  20  of the filter  12 . The first disengaged position of manifold  14  is high enough (i.e., sufficiently spaced from the lower manifold  16 ) in the module such that the filter  12  can be lifted off (vertically, in the direction toward upper manifold  14 ) of lower manifold  16  and removed. In the second engaged position, coupling  20  is received by receiver  19 , engaging the filter unit  12  in place in the module. Although both the upper manifold  14  and lower manifold  16  could be movable, preferably one is movable and the other is stationary in this embodiment.  
         [0041]     In a preferred embodiment of the assembly illustrated in  FIG. 1 , each upper manifold  14  contains a valve  25  that is actuated by engagement of the filter unit  12  with the manifold  14 , and more specifically, by engagement of the coupling  20  with the manifold  14 . Upon attachment of the filter unit  12  to the manifold  14 , the valve  25  is forced open by contact with an actuating member  7  in the coupling  20 , allowing fluid communication between the filter unit  12  and the manifold  14 . In the embodiment shown, the opening of the valve  25  is caused by contact between the actuating member  7  in coupling  20  and the valve stem  30 , which forces the valve in the vertical direction (as depicted in  FIG. 1 ), unseating the valve and allowing fluid to flow past it. When the filter unit  12  is removed from the manifold  14 , valve spring  13  biases the valve  25  back to its seated, closed position, preventing leakage from the manifold  14 .  
         [0042]     Also in a preferred embodiment of the assembly illustrated in  FIG. 1 , each filter unit  12  includes a valve  26  that is actuated upon engagement of the filter unit  12  with the manifold  16 . Upon attachment of the filter unit  12  to the manifold  16 , the valve  26  is opened by contacting actuating member  29 , allowing fluid communication between the manifold  16  and the filter unit  12 . When the filter unit  12  is removed from the manifold  16 , valve spring  11  biases the valve  26  to its seated, closed position, preventing leakage from the filter unit  12 .  
         [0043]     One such suitable valve  26  is shown in greater detail in  FIG. 2 . Lower manifold  16  includes a fluid passageway  23  providing fluid communication to (or from) filter unit  12 . The manifold  16  has a preferably cylindrical projection  22  which receives a corresponding receiving end  21  of filter unit  12  whose inside diameter is greater than the outside diameter of projection  22 . The projection  22  (and/or the receiving end  21 ) has means for creating a sealed fit with the filter unit  12 , such as an O-ring.  28 . A stationary valve actuator  29  is positioned in manifold  16  such that attachment of the filter unit  12  to the manifold  16  causes the valve stem  30  of T-shaped (in cross-section) valve  26  to engage the actuator  29 , forcing the valve in the vertical direction as depicted by the arrow in  FIG. 2 , allowing fluid to flow about the valve  26  and into the filter unit  12 . A spring or the like (not shown) preferably seats on the upper surface  44  of the valve  26 , biasing the valve  26  towards its closed position where it seats against the base  32  of the housing or filter  12 . In a bottom opening, one can rely upon gravity, however it is preferred to use some other device to assist in the closure. When the filter unit  12  is disengaged from the manifold  16 , the valve  26  seals against the housing of the filter unit  12  at  32  as shown in  FIG. 3 , preventing fluid flow between the manifold  16  and the filter unit  12 , and preventing leakage out of the filter unit  12 . Those skilled in the art will appreciate that the configuration of the attachment between the manifold  16  and the filter unit  12  is not critical; for example, the fittings could be reversed, with the manifolds being inserted internally into the projections on the filter unit  12 . Similarly, since the filter unit  12  is connected to a manifold at an inlet and an outlet, the inlet can have a different connection from the outlet.  
         [0044]      FIG. 2   a  shows greater detail of the design of the valve  26  located in receiving end  21  of filter unit  12 , which is received by a corresponding recess  49  in manifold  16 . Spring  11  is illustrated biasing the valve  26  towards its sealed position against shoulder  48  of the receiving end  21 . O-ring  28  seals the end  21  in the recess  49  of the manifold  16 . Actuator  29  is positioned to engage the valve stem as in the embodiment of  FIG. 2 , to move the valve in the direction of the arrow and unseat it from shoulder  48 , allowing fluid to flow about the valve.  
         [0045]      FIG. 4  illustrates a second embodiment of the filter unit valve for creating a dripless, rapid disconnect filter assembly. The valve in this embodiment is a ball valve, wherein a spherical member  34  having a density greater than the density of the fluid is housed in a cavity  35  formed in filter unit  12 . The cavity is defined in part by at least two spaced opposing arms  46 ,  47  which converge at their free ends as shown, so that the space between their free ends is smaller than the diameter of the spherical member  34 , thereby containing the spherical member  34  and preventing the spherical member  34  from escaping from the cavity  35 . Preferably there are two pair of spaced opposing arms. More specifically, the free end of each arm preferably terminates in facing ends  46   a ,  47   a  such that the distance between the ends on opposing arms is smaller than the diameter of spherical member  34 , thereby providing a stop and limiting the vertical movement of spherical member  34  in cavity  35 . A fluid passageway  36  is provided below spherical member  34 , providing fluid communication to fluid path  22  of manifold  16 . As the fluid flows from manifold  16  into passageway  36 , it exerts a pressure on spherical member  34 , causing spherical member  34  to travel in the direction of arrow  37  in the cavity  35  and assume the open position shown with phantom lines in  FIG. 4 , and shown in greater detail in  FIG. 4   a . Due to the geometry of the cavity  35 , with the spherical member in the open, phantom-line position, fluid is allowed to flow around the spherical member  34  and enter the filter unit  12  ( FIG. 4   a ). However, when the fluid flow from the manifold  16  stops, the spherical member  34  returns to the closed position, disrupting the fluid communication between passageway  36  and cavity  35  and preventing fluid from escaping into fluid passageway  36  and leaking out of the filter unit  12 . The filter unit  12  can now be removed from the manifold without leakage. Those skilled in the art will appreciate that although a spherical member  34  is preferred, other shapes may be suitable provided the member seals in its closed position and can be moved to its open position by the pressure exerted by the fluid flowing from the manifold. The filter unit  12 , which is preferably constructed of a disposable material, seals onto manifold  16  by any suitable means.  FIG. 4  shows a recess or socket  60  formed in filter unit  12 , shaped to receive male end  62  of manifold  16 . Annular O-ring  28  in the end  62  ensures a seal.  FIG. 4   b  shows an alternative embodiment where the male end coupling  63  is on the filter unit  12  and is received by socket  64  in the manifold  16 . Annular O-ring  28  is shown placed in the coupling  63  is this embodiment. Those skilled in the art will appreciate that in any embodiment, more than one O-ring may be used, or some other sealing device may be used instead or together with the O-ring(s).  
         [0046]     Since the proper orientation of the filter  12  may be critical,  FIG. 5  illustrates an embodiment of the filter  12  and manifold that prevents improper installation of the filter  12 . Thus, upper manifold  114  has a male extension  110  having a fluid pathway  223 . The male extension  110  is sealingly received by corresponding recess  235  in the outlet of filter unit  12 . Lower manifold  116  has a different configuration than upper manifold  114 . For example,  FIG. 5   a  shows lower manifold  116  having a recess  225  to sealingly receive a corresponding male extension  230  of the inlet of filter unit  12 . Since the configurations of the inlet and outlet of filter unit  12  are different, the filter unit  12  can be installed only one way in the manifolds  114 ,  116 . Also shown are spaced legs  205  on filter unit  12 , which allow the filter unit  12  to stand on its own. Preferably the legs  205  extend below the male extension  230 , so that when the filter unit  12  is standing on a substrate  201 , the inlet fitting male extension  230  is not exposed to (and contaminated by) that substrate. Suitable valving (not shown) is used in the inlet and outlet to control fluid flow, such as that shown in  FIGS. 2 and 2   a.    
         [0047]      FIG. 6  illustrates an embodiment of the manifold/filter assembly where multiple connections therebetween are made. Male extensions  110 ,  110   a  and  110   b  of upper manifold  114  are sealingly received by corresponding recesses  235 ,  235   a  and  235   b  in the filter unit  12 . A single connection between filter unit  12  and lower manifold  116  is shown, thereby again ensuring orientation of the filter unit  12 . Although three upper connections and one lower connection are shown, the skilled in the art will appreciate that more or less connections could be used at either end, provided the proper orientation is provided. In addition, one or both of the upper and lower manifolds could be made to move vertically, facilitating installation and removal of the filter unit  12 . Suitable valving is used in each connection to control fluid flow.  
         [0048]      FIGS. 7 and 7   a  illustrate a further embodiment of the present invention. Communication and connection of filter unit  12  to tipper and lower manifolds  114 ,  116  are made with elbow couplings  250 ,  250 ′. Each elbow fits into a correspondingly shaped socket  251 ,  251 ′ in the respective manifold. An alignment rib  255  can be provided on the filter unit  12  as shown, which slides into a correspondingly shaped alignment slot  256  formed in the upper manifold  114 . A similar rib/slot arrangement can be used for the lower manifold  116  as well. This ensures proper alignment of the filter unit  12  as it is slidingly received by the manifolds. Indicating means  280  such as a microswitch can be used to turn off the system (and stop fluid flow) when the filter  12  is removed. A latch mechanism (not shown) or other locking means is used to lock the filter unit  12  to the manifolds when in use, preventing premature disengagement.  
         [0049]      FIGS. 8, 8   a  and  8   b  illustrate an embodiment similar to that shown in  FIG. 7 , except that only upper coupling or fitting  250  is shaped as an elbow; lower coupling or fitting  250 ″ is a ball design, preferably made of a rigid polyolefin, such as polypropylene, or stainless steel or other metal, depending upon the application. To install the filter unit  12  into the system, the lower fitting  251 ″ is first inserted into lower manifold  116  as shown in  FIG. 8 . This is accomplished by tilting the filter unit  12  relative to the manifold, as shown. Once the ball fitting  251 ″ is inserted into the corresponding recess  251  in the lower manifold  116 , the upper elbow fitting  250  is then inserted into socket  252  in upper manifold  114  as shown in  FIG. 8   a . The elbow fitting  250  can be chamfered such as at  300  to facilitate its entry into socket  251 . One or more guides  260  can be used to properly align and orient the filter unit  12 . The configuration of the ball design  250 ″ and corresponding socket  251  allows the ball  250 ″ to swivel in the socket  251 , thereby providing some “play” as the filter unit  12  is moved from the tilted position of  FIG. 8  to the engaged position of  FIG. 8   a . This facilitates installation and removal of the filter device  12  at an angle, without requiring that either manifold  114  or  116  move. The depth of the socket  251  is preferably sufficient to allow movement in the axial (downward) direction to enable the upper fitting to be properly aligned with the upper manifold  114 . In addition, since the filter device  12  has a tendency to move in the axial direction (i.e., the direction of flow) when under pressure, the depth of the socket  251  can accommodate this movement as well. Regardless of the particular location of the ball  250 ″ in the socket  251  however, the annular O-ring  28  creates a suitable seal. The diameter of the ball  250 ″ and the length of the socket  251  determines the degree to which the filter unit  12  can be tilted with respect to the axis of fluid flow for installation and removal. Preferably, the filter unit  12  can be tilted at least about 20 degrees away from vertical.  
         [0050]     More specifically, with reference to  FIG. 10 , for filter units having a length (from fitting to fitting, as shown in  FIG. 10 ) in the range of 4-8 inches, the tilt angle range necessary for installation and removal with stationary manifolds is an angle θ of from about 8° to about 15° or greater. For filter units having a length in the range of about 8-18 inches, the tilt angle range is from about 5° to about 13° or greater. For filter units having a length of about 18-40 inches, the tilt angle range is an angle of from about 2° to about 5° or greater.  
         [0051]      FIGS. 8   c ,  8   d  and  8   e  show alternative configurations for the fitting  251 . An important factor among the various embodiments is a decrease in diameter of the fitting from a maximum diameter where the fitting engages and seals against the walls of the socket  252 , towards the filter housing  12 . Also, preferably the fitting is connected to the housing  12  with a neck  255  having a diameter smaller than the maximum diameter of the fitting  251 , so that the unit is easily tiltable with respect to the axis of fluid flow and can be readily inserted into (or removed from) the socket  252 . These parameters provide the necessary relief to allow the unit to pivot in the socket  252  so it can be connected or disconnected from stationary manifolds. In  FIG. 8   c , the fitting  251   a  includes an elongated neck portion  255  extending from filter unit  12 , terminating in a semispherical portion having an O-ring about its portion of maximum diameter to seal in the socket  252 . The neck  255 , being of smaller diameter than the fitting  251   a , allows the pivoting action shown. The entry edges of socket  252  can be chamfered (not shown) to facilitate entry of the fitting  251  therein.  FIG. 8   d  illustrates a further embodiment of the fitting  251  where a polygonal shape is used. Again, the maximum diameter of the fitting  251   b  is where the fitting engages and seals against the walls of the socket  252 .  FIG. 8   e  is a further embodiment, where fitting  251   c  has a substantially rectangular shape. Chamfered edges  253  can facilitate entry of the fitting  251   c  into the socket  252 .  FIG. 8   f  shows a prior art configuration where there is no reduction in diameter of the length of the fitting. As a result, the housing  12  cannot be tilted to a sufficient angle for installation into a stationary manifold.  
         [0052]      FIGS. 10, 10   a ,  10   d  and  10   e  illustrate further embodiments of the present invention, wherein the upper coupling uses a simple planar face seal and fits into a corresponding slot in the upper manifold  214 . The upper coupling  350  is T-shaped in cross-section, with a central passageway  351  allowing for fluid communication between the filter and the manifold  214 . An O-ring  28  placed in a groove on the top surface of the coupling  350  can seal in the manifold slot  360 . Alternatively, the O-ring  28  can be located in a groove in the slot  360  itself. In the embodiment of  FIG. 10  and  10   a , lower coupling is a swivel similar to that shown in  FIG. 8 , however the ball  450  is shown as part of the lower manifold  216 . The ball  450  is received in recess  451  in the filter assembly  12 , which is appropriately dimensioned to enable the tilting shown in  FIG. 10  and insertion of the upper T-shaped fitting  350  in the slot  360  of upper manifold  214 . Annular O-ring  28  seals about the ball  450  as shown. The ball includes a passageway  465  that extends into manifold  216  for fluid communication between the manifold and the filter  12  when assembled. In the embodiment of  FIGS. 10   d  and  10   e , the ball  450  is placed on the assembly  12  as in  FIG. 8 , and is received in a recess in the lower manifold  216 . The recess  451  is appropriately dimensioned to receive the ball  450 , and the space between the upper and lower manifolds (which are preferably stationary) is such to enable the tilting shown in  FIG. 10   d  and insertion of the upper T-shaped fitting  350  in the slot  360  of the upper manifold  214 . The ball  450  is sealed in the recess such as by an annular O-ring  28 . A latch  375  can be used on upper (or lower) manifold  214  to secure the device in place. For example, with reference to  FIGS. 10   b  and  10   c , a spring  376  biases against latch  375  in the uninstalled position of  FIG. 10   c , and biases the fitting  350  against the latch  375  in the installed position of  FIG. 10   b . The free end of the latch  375  can be chamfered as shown, to assist the T-shaped fitting  350  in entering the slot  360 . By using the swivel fitting, both the upper and lower manifolds can be stationary.  FIG. 10  shows the filter  12  in a tilted (with respect to manifold  214 ) position, and  FIG. 10   a  shows the filter  12  in an engaged position in the manifold  214 .  
         [0053]      FIGS. 11 and 11   a  show a bottom fitting similar to that of  FIGS. 10 and 10   a , with stationary lower manifold  216 . However, in this embodiment, the top fitting is connected to a movable manifold portion. Specifically, the upper manifold  314  includes a stationary portion  314   a  and a movable portion  314   b . The stationary portion  314   a  includes a male extension  320  having a fluid passageway therein. The movable portion  314   b  includes a recess  330  that receives the male extension  320 , and a slot  460  that receives the upper coupling  350 ′ of the filter assembly  12 . The upper coupling  350 ′ includes a recess  380  that receives male extension  320  when the movable portion  314   b  is in its manifold-engaging position as shown in  FIG. 11   a . An annular O-ring about the extension  320  seals in the recess  380 . Since in this embodiment the upper manifold has a movable portion, it is not critical that a swivel fitting be used as the lower fitting; other suitable fittings such as that disclosed in the embodiment of  FIG. 1  could be used such that the filter assembly is connected without the titling operation shown in  FIG. 11 .  
         [0054]      FIG. 12  shows a further embodiment, wherein the fittings on both the top and bottom are similar to the T-shaped design of  FIG. 10 . The filter  12  slides into the two manifolds virtually simultaneously, and preferably one or both of the upper and lower manifolds is movable in the axial direction to account for variation in filter length amongst various filters and allow connection and engagement of the filter.  
         [0055]     The embodiment of  FIG. 13  shows a stationary upper manifold having a male extension  419 , defining a passageway  421 . The extension  419  is received by a correspondingly-shaped recess  480  in extension  460  of filter  12 . Annular O-ring  28  creates a seal within the recess  480  when the extension  419  is engaged therein. The opposite end of filter  12  includes an extension  440  that seals in recess  481  of the lower manifold  416 . Annular O-ring  28  seals in the recess  481  when the extension  440  is engaged therein.