Abstract:
A water treatment system includes a filter module and a reverse osmosis module secured to the filter module. The filter module contains two filter cartridges. The modular structure of the components enables the filter module to have the two filter cartridges connected as separate pre and post filters or connected in series as a single two-stage filter. Similarly the modularity permits multiple reverse osmosis modules to be connected is a daisy chain manner for increased treatment capacity. A novel bracket structure aligns ports of the filter module with corresponding ports on the reverse osmosis module.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     Not applicable.  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not applicable.  
       BACKGROUND OF THE INVENTION  
       [0003]     1. Field of the Invention  
         [0004]     The present invention relates to apparatus for treating water to remove chemicals and other impurities, and more particularly to reverse osmosis water filtration systems.  
         [0005]     2. Description of the Related Art  
         [0006]     Reverse osmosis (RO) water treatment systems are often located under a countertop or sink in a kitchen or adjacent another place at which purified water is desired to be provided. The typical system comprises a pre-filter, that employs a conventional filter medium, to remove relatively large particles as all the water being treated passes through the medium. The water exits the pre-filter and enters a reverse osmosis unit.  
         [0007]     Reverse osmosis is a method that separates solutes from a solution by causing the solvent (such as water) to float through a membrane at pressures higher than normal osmotic pressure. The osmosis phenomenon is manifested by the diffusion of a solvent through a semi-permeable membrane from a region of greater osmotic pressure to a region of lower osmotic pressure. As the solvent diffuses through the membrane, dissolved substances, such as salts, minerals and other contaminants, are left behind so that the region of lower osmotic pressure has a lower concentration of dissolved substances. The remaining dissolved substances are flushed from the higher pressure side of the membrane through a restricted drain aperture that creates the increased pressure within the unit. The fluid from the drain aperture may be sent to a sewer system or recycled through the water treatment system by a pump so that less water is wasted.  
         [0008]     The treated water exiting the reverse osmosis unit may pass through an optional post-filter to improve the taste of that water. A tank may also be provided on the output of the treatment apparatus to store the purified water. When needed, the purified water is drawn from the tank.  
         [0009]     Depending upon the characteristics of the untreated water at a particular installation, several pre-filters may be utilized and various pluralities of reverse osmosis units may be connected in parallel or series to treat the water and provide the necessary flow volume. Therefore, it is desirable to design components of the reverse osmosis water treatment system, which can be connected in various combinations and numbers to provide the necessary level of treatment required for a particular instillation.  
       SUMMARY OF THE INVENTION  
       [0010]     A water treatment system includes a filter module and a reverse osmosis module secured to the filter module. The filter module has a first manifold with a first filter cartridge and second filter cartridge mounted thereto. The first manifold has a filter inlet port and a filter outlet port. The first filter cartridge has a first inlet connected to the filter inlet port and has a first outlet. The second filter cartridge has a second inlet and having second outlet connected to the filter outlet port.  
         [0011]     The first reverse osmosis module secured to the filter module and including a second manifold with a first RO inlet port, a first RO outlet port and a first drain port, the first RO inlet port being connected to the filter module and receiving water therefrom.  
         [0012]     The modularity of the water treatment system enables several different configurations of the filter module to be connected to the first reverse osmosis module. In one version, the filter module is configured with the first filter cartridge acting as a pre-filter for the first reverse osmosis module and the second filter cartridge is connected as a post-filter. In another version, the two filter cartridge are coupled in series to function as a dual-stage pre-filter. The modularity also enables. multiple reverse osmosis modules to be connected in a daisy chain to increase the water treatment capability of the system. 
     
    
     DESCRIPTION OF THE OF THE DRAWINGS  
       [0013]      FIG. 1  is a block schematic diagram of a first water treatment system having a reverse osmosis module with a filter module containing a pre-filter and a post-filter;  
         [0014]      FIG. 2  is an isometric view of the first water treatment system;  
         [0015]      FIG. 3  is a cross sectional view through a first manifold at the upper portion of the filter module;  
         [0016]      FIG. 4  is a cross sectional view vertically through the filter module;  
         [0017]      FIG. 5  is a cross sectional view through a second manifold at the upper portion of the reverse osmosis module;  
         [0018]      FIG. 6  is a block schematic diagram of a second water treatment system having a dual stage pre-filter module and two reverse osmosis modules;  
         [0019]      FIG. 7  is an isometric view of the second water treatment system; and  
         [0020]      FIG. 8  is a cross sectional view through the manifold of the dual stage pre-filter module. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]     With initial reference to  FIG. 1 , a first water treatment system  10  comprises a filter module  12  and a reverse osmosis (RO) module  14 . The filter module  12  receives untreated water from a source at a filter inlet port  16 , which is connected to a first inlet  17  of a pre-filter cartridge  18 . The pre-filter cartridge  18  contains a filter medium, such as a body of a spun fiber material, through which the water flows to trap relatively large particles. The output water from the pre-filter cartridge  18  flows from a first outlet  19  to a first intermediate port  20  of the filter module  12 . The filter module also has a second intermediate port  22  that is connected to a second inlet  23  of a post-filter cartridge  24  which contains a filter medium, such as activated charcoal, to improve the taste and odor of the water. The output of the post-filter cartridge  24  flows from a second outlet  25  to a filter outlet port  26 , which in the case of the first water treatment system  10  supplies purified water to the end user.  
         [0022]     The first intermediate port  20  of the filter module  12  is connected by a tube  32  to a first RO inlet port  30  of the reverse osmosis module  14 , which thereby receives water from the pre-filter cartridge  18 . The reverse osmosis module  14  has first and second reverse osmosis cartridges  34  and  36  with inlets that are connected to the first RO inlet port  30 . Each of the two reverse osmosis cartridges has a conventional semi-permeable membrane which filter water flowing there through. The treated water passes to cartridge outlets  38  and  40  that are connected to a first RO outlet port  42 . The first RO outlet port  42  is coupled by a tube  43  to the second intermediate port  22  of the filter module  12 . Therefore, the water treated in the two reverse osmosis cartridges  34  and  36  is fed back through the post-filter cartridge  24  to produce purified water at the filter outlet port  26 . Each of the reverse osmosis cartridges  34  and  36  also has a drain outlet  35  from which some of the untreated water, carrying a high concentration of solutes, exits the cartridges. The drain outlets  35  are connected to first and second drain ports  44  of the reverse osmosis module  14 .  
         [0023]     The first water treatment system  10  has a modular configuration, illustrated in  FIG. 2 , in which the filter module  12  and the reverse osmosis module  14  are attached abutting each other and are fluidly coupled. The two cylindrical filter cartridges  18  and  24  of the filter module  12  are mounted to a filter manifold  50  in which the filter inlet port  16 , the filter outlet port  26 , and the first and second intermediate ports  20  and  22  are located. The filter manifold  50  has internal passageways that interconnect selected ports with the pre-filter cartridge  18  and the post-filter cartridge  24 . With reference to  FIG. 3 , the filter inlet port  16  opens into a first inlet passage  52  that leads to an aperture  54  through the bottom of the manifold and into the outer perimeter inside the pre-filter cartridge  18 . A second aperture  56  through the bottom of the filter manifold  50  is located at the center of the pre-filter cartridge  18  and is within a first outlet passage  58  that leads to the first intermediate port  20 .  
         [0024]     With reference to  FIGS. 3 and 4 , the fluid entering the filter module  12  via the filter inlet port  16  flows through the first aperture  54  into the pre-filter cartridge  18  and around the filter medium  65  therein. The water in the pre-filter cartridge  18  passes through the filter medium  65  to the cartridge&#39;s central bore  68  and then upward through the second aperture  56 , exiting the filter module  12  via the first intermediate port  20  on the opposite side of the filter module  12  from the filter inlet port  16 .  
         [0025]     The second intermediate port  22  on that opposite side of the filter module  12  communicates with a second inlet passage  60  that connects to a third aperture  62  in the bottom of the filter manifold  50  that opens inside the perimeter of the post-filter cartridge  24 . After passing through the filter medium  69  in the post-filter cartridge  24 , the water flows through a centrally located fourth aperture  64  in the bottom of the filter manifold  50 . This fourth aperture  64  is connected by a second outlet passage  66  in the manifold  50  to the filter outlet port  26 .  
         [0026]      FIG. 5  illustrates the interior passages of a second manifold  72  that is part of the reverse osmosis module  14 . The first RO inlet port  30  opens into an internal RO inlet passage  80  that communicates with a first RO aperture  82  through the bottom of the second manifold  72  and into the first reverse osmosis cartridge  34  in  FIG. 2 . The RO inlet passage  80  also opens through a second RO aperture  84  into the second reverse osmosis cartridge  36 . The RO inlet passage  80  leads to a second RO inlet port  31  of the second manifold  72 . Thus, the first and second RO apertures  82  and  84  provide the RO inlets of both reverse osmosis cartridges  34  and  36 . The first and second RO inlet ports  30  and  31  are in direct fluid connection, which as used herein means that these ports are connected together by a conduit without any intervening element. The outlets  38  and  40  of those reverse osmosis cartridges  34  respectively communicate with first and second RO outlet apertures  86  and  90  in the bottom of the manifold  72 . The RO outlet apertures  86  and  90  are connected by an RO outlet passage  88  to the first RO outlet port  42  and a second RO outlet port  41  on opposite sides of the second manifold  72 . A drain passage  92  winds in a serpentine path through the second manifold thereby providing a direct fluid connection of the first and second drain ports  44  and  45 . A pair of drain apertures  94  and  96  open through the bottom of the second manifold into the drain passage  92  which provide the drain outlets  35  of both reverse osmosis cartridges  34  and  36 .  
         [0027]     It should be noted that there is an inlet port, an outlet port and a drain port on the opposite sides of the reverse osmosis module  14  enabling several of the reverse osmosis modules to be connected side by side. Such daisy chaining enables a plurality of reverse osmosis cartridges to be connected in parallel for increased water purification capability. In a particular application, any unused ports are closed by a plug. The port arrangement also facilitates connecting the filter module  12  to a reverse osmosis module  14  in a modular configuration.  
         [0028]     The individual modules of the water treatment system have brackets for attaching them together in a single structural assembly, as illustrated in  FIG. 2 . Specifically, the filter module  12  has a first bracket  70  extending around and projecting outwardly from four sides of the filter manifold  50 . The second manifold  72  of the reverse osmosis module  14  includes a similar second bracket  74  extending around and outwardly there from on four sides. With reference to  FIGS. 3 and 5 , the first and second bracket assemblies  70  and  74  have keys  71 , in the form of annular bosses, on one side and the opposite side has apertures  73  that are sized to receive the keys. Thus in the assembled first water treatment system  10 , the bracket keys  71  of the reverse osmosis module  14  fit into the bracket apertures  73  of the filter module  12  to ensure proper orientation of those modules. Sets of nuts and bolts  76  pass through the bracket bosses and apertures to secure the adjacent modules together.  
         [0029]     When the two modules  12  and  14  are secured directly together, the first intermediate port  20  of the filter module  12  aligns with the first RO inlet port  30  of the reverse osmosis module  14 . As used herein, the term “secured directly” refers to two components, in this case the two modules  12  and  14 , being attached with one component contacting the other, as opposed to each being attached separately to one or more intermediate elements which link the two components. As a result of that direct securing, a straight tube  32  is secured in each of those ports to provide a conduit between the two modules. The first RO outlet port  42  of the reverse osmosis module  14  similarly aligns with the second intermediate port  22  of the filter module  12  so that another straight tube  43  provides a conduit between those latter ports. The abutting brackets  70  and  74  provide a fixed spacing between the aligned ports so that the two tubes  32  and  43  can be supplied to the installer precut to the proper lengths. Each of the ports  16 ,  20 ,  22 ,  26 ,  30 ,  42  and  44  of the two modules  12  and  14  preferably utilize standard compression fittings.  
         [0030]     An example of another modular configuration of a second water treatment system  100  is depicted in  FIGS. 6 and 7  in which a dual pre-filter module  102  is combined with two reverse osmosis modules  131  and  132  that are connected in tandem. Specifically, the dual pre-filter module  102  has two filter cartridges  105  and  106  coupled in series. Typically, the first pre-filter cartridge  105  has a medium that removes relatively large particles, whereas the medium of the second pre-filter cartridge  106  removes smaller particles.  
         [0031]     With reference to  FIG. 8 , the manifold  112  of the dual pre-filter module  102  has a filter inlet port  108  that receives the source water to be treated. An inlet passage  114  conveys the water from the filter inlet port  108  to a first inlet aperture  116  into the first inlet  101  ( FIG. 6 ) of the first pre-filter cartridge  105  from which the water flows exits through a first outlet  103  back into the manifold via a first outlet aperture  118 . An intermediate passage  120  connects the first outlet aperture  118  to a second inlet aperture  122  communicating with the second inlet  107  of the second pre-filter cartridge  106 . The filtered water leaves the second pre-filter cartridge  106  via a second outlet  109  and a second outlet aperture  124  in the manifold, travels through an outlet passage  126 , and exits the dual pre-filter module  102  via a filter outlet port  110 .  
         [0032]     Referring again to  FIGS. 6 and 7 , the filter outlet port  110  of the dual pre-filter module  102  is connected to the first RO inlet port  30  of the first reverse osmosis module  131  by a tube  138 . Both reverse osmosis modules  131  and  132  have the same construction as the reverse osmosis module  14  of the first water treatment system  10 , described previously. However in the modular configuration of the second water treatment system  100 , the first and second reverse osmosis cartridges  134  and  135  of the first reverse osmosis module  131  and the third and fourth reverse osmosis modules  136  and  137  of the second reverse osmosis module  132  are all connected in parallel.  
         [0033]     With respect to that parallel connection, the first RO inlet port  30  of the first reverse osmosis module  131  is coupled by the RO inlet passage  80  to that module&#39;s the second RO inlet port  31 . That second RO inlet port  31  is connected by a tube  140  to the first RO inlet port  30  of the second reverse osmosis module  132 . Similarly the second RO outlet port  41  of the first reverse osmosis module  131  is connected by a second tube  142  to the first RO outlet port  42  of the second reverse osmosis module  132 , and the first drain port  44  of the first reverse osmosis module is coupled by a third tube  143  to the second drain port  45  on the second reverse osmosis module. The first drain port  44  of the second reverse osmosis module  132  is connected to a drain line for the second water treatment system  100  and the second RO outlet port  41  of the second reverse osmosis module  132  provides the outlet for the purified water.  
         [0034]     The first and second reverse osmosis modules  131  and  132  also can be connected in other configurations. For example, the second RO outlet port  41  of the first reverse osmosis module  131  can be connected to the first RO inlet port  30  of the second reverse osmosis module  132  so that the two modules are in series. Alternatively, the first drain port  44  of the first reverse osmosis module can be coupled to the first RO inlet port  30  of the second reverse osmosis module  132 . In this implementation, the second RO outlet port  41  of the first reverse osmosis module  131  is connected to the first RO outlet port  42  of the second reverse osmosis module  131 . Here the second reverse osmosis module  132  processes some of the first RO module&#39;s drain water so that less water flows into the drain system thereby conserving water.  
         [0035]     Additional reverse osmosis modules can be attached together. The modular configuration of the present water treatment systems enables various numbers of pre-filter cartridges, post-filter cartridges, and reverse osmosis cartridges to be connected together to provide the amount of water treatment capacity to satisfy the requirements of a particular installation.  
         [0036]     The foregoing description was primarily directed to a preferred embodiment of the invention. Although some attention was given to various alternatives within the scope of the invention, it is anticipated that one skilled in the art will likely realize additional alternatives that are now apparent from disclosure of embodiments of the invention. Accordingly, the scope of the invention should be determined from the following claims and not limited by the above disclosure.