Abstract:
An in-line, in-pool system for chemically treating water in conjunction with an automatic swimming pool cleaner is disclosed. Incorporating a head and a cartridge, the system is design for placement within a swimming pool for treating water therein. Purification media may be placed within the cartridge to effect sanitization of the water.

Description:
This application is a continuation-in-part of and claims, under 35 U.S.C. § 120, benefit of the filing date of U.S. patent application Ser. No. 08/964,782 (now U.S. Pat. No. 5,882,512), filed Nov. 5, 1997, entitled “Automatic Swimming Pool Cleaners and Associated Components and Systems.” 
    
    
     FIELD OF THE INVENTION 
     This invention relates to water purification systems and more particularly to equipment and techniques for purifying water contained in swimming pools using devices adapted to be placed within pools intermediate automatic swimming pool cleaners and inlets or outlets of the filtration systems of such pools. 
     BACKGROUND OF THE INVENTION 
     Numerous commercially-available automatic swimming pool cleaners exist. Although some utilize electricity to power internal pumps and motors, many connect instead (indirectly) to pumps located externally of the pools. Using flow of water to or from the pumps, the automatic pool cleaners themselves traverse the bottoms (and sometimes walls and other surfaces) of pools, vacuuming debris resting thereon. 
     Automatic pool cleaners connected, indirectly, to the inlet of pumps are often called “suction-side” cleaners, as the suction created by the pumps draws, or evacuates, water through the cleaners. One example of a suction-side cleaner is illustrated in U.S. Pat. No. 5,014,382, which patent is incorporated herein in its entirety by this reference. The cleaner includes a valve (which may but need not necessarily be a diaphragm), which in use periodically interrupts the flow of water through the cleaner body. The interruption in flow assists in moving the cleaner about the bottom (and other surfaces) of a swimming pool. 
     By contrast, automatic pool cleaners connected (again indirectly) to outlets of pumps are termed “pressure-side” cleaners. U.S. Pat. No. 4,835,809 to Roumagnac, also incorporated herein in its entirety by this reference, discloses an example of such a pressure-side cleaner. According to the Roumagnac patent, the cleaner connects to the “recycle mouth,” or return line, of the pool filtration system. Flow of pressurized water through the cleaner creates a low-pressure region within its body, permitting aspiration of debris-laden water from the pool into the body. 
     Although capable of removing detritus from pools, automatic swimming pool cleaners historically have been unable to assist in purifying water chemically. Instead, such purification has sometimes occurred using devices wholly separate from the automatic cleaners. These devices frequently include pressure vessels and are located externally of the pools themselves. 
     U.S. Pat. No. 4,504,387 to LeMire, et al. discloses exemplary equipment for purifying bodies of water, including swimming pools, spas, and hot tubs, utilized recreationally by human beings. As shown in FIG. 1 of the LeMire, et al. patent, swimming pools conventionally include pumps, filters, and recycling systems; while a pump is operating, water is continually withdrawn from a pool, passed through a filter, and returned to the pool via the recycling system. By positioning water purification equipment between the outlet of the pump and the return mouth of the pool, pressurized water exiting the pump can be purified prior to its return to the pool. 
     Water purification equipment of the type detailed in the LeMire patent is, as suggested above, designed for placement outside the boundaries of the pool. Consequently, it includes a stand or base on which an outer casing is positioned. The stand maintains the casing in an upright stance, whether located above soil, concrete, or asphalt. 
     The casing, moreover, contains an inlet and an outlet, both of which are plumbed into the recycling system of the pool. As a result, the water purification equipment is closed to the ambient environment and receives only water passed from the outlet of the pump. By this reference applicants incorporate herein the entirety of the LeMire, et al. patent, as well as the entireties of U.S. Pat. Nos. 5,352,369 to Heinig, Jr., 5,660,802 to Archer, et al., and 5,772,896 to Denkewicz, Jr., et al., which disclose other equipment and techniques for purifying water. 
     U.S. Pat. No. 5,269,913 to Atkins, additionally incorporated herein in its entirety by this reference, describes a mechanical debris trap for use in connection with suction-side automatic swimming pool cleaners. As recited in the Atkins patent, the trap has an internal strainer, or filter, and 
     a “T” configuration, with the inlet/outlet tube making up the top of the “T” and a housing containing the filter and a relief valve, drain, or similar device making up the base of the “T.” The inlet/outlet tube is intersected at midpoint by a tube or downspout perpendicular to the inlet/outlet tube that prevents direct flow through the inlet/outlet tube but is open on the inlet side. The perpendicular tube penetrates the filter and terminates in an open end within the filter. 
     See Atkins, col. 2, lines 10-18. The trap is spliced into a flexible hose leading to an automatic pool cleaner; in use, “[w]ater and debris entering the inlet are directed downward into the interior of the filter by the perpendicular tube,” id., lines 32-34, with debris being trapped within the filter and water migrating through the filter to the outlet of the trap. 
     The debris trap of the Atkins patent additionally (optionally) includes a relief valve in the bottom of the housing. As described therein, the valve “allows water to be drawn into the housing to balance the fluid flow to or from the cleaner head.” Id., lines 40-42. Such drawing occurs when the pool cleaner or a system regulator valve becomes plugged or blocked and is intended to equalize the pressure within the overall filtration system. See id., col. 4, lines 8-14. The primary water flow through the trap, therefore, remains via the inlet/outlet tube. 
     Neither the LeMire nor the Atkins patent details equipment adapted to purify water chemically while the water is within a swimming pool. Likewise, neither patent addresses use of any equipment designed to cooperate with both pressure- and suction-side automatic swimming pool cleaners. Accordingly, for at least these reasons an in-line, in-pool system for chemically treating water in conjunction with an automatic swimming pool cleaner (whether suction- or pressure-side) would be useful. 
     SUMMARY OF THE INVENTION 
     The present invention provides such a system. Incorporating a head and a cartridge, the system is designed for placement within swimming pools so as chemically to treat water within the volumes of the pools. The device of the system additionally is intended to be positioned intermediate an automatic (or conceivably, in some cases, manual) swimming pool cleaner and either the inlet or the outlet of the pool filtration system, thus cooperating with the automatic pool cleaner employed in each pool. 
     In at least some embodiments of the invention, the same cartridge (and possibly the same head) may be used regardless of whether the associated automatic pool cleaner is a suction- or pressure-side cleaner. In these embodiments the cartridge additionally includes media adapted to sanitize water. Although the media may be similar to any of those described in the Heinig, Jr. or Denkewicz, Jr., et al. patents, it need not necessarily be so, and any other suitable water purification chemistry may be used instead. The media within the cartridge can be disposable if desired, in which case the cartridge may be opened to remove the media and re-closed following its replacement. Alternatively, the cartridge itself may be replaced. 
     Openings in the top and bottom portions of the cartridge permit water to flow completely therethrough, facilitating contact of the to-be-sanitized water with the media contained therein. An inlet/outlet tube, in some respects similar to that shown in the Atkins patent (and preferably, although not necessarily, tubular in shape), is formed in the head. The tube is not wholly continuous through the head, but rather includes either a secondary opening or a gap (or cavity) between the inlet and outlet to permit fluid communication with the cartridge. 
     In embodiments of the device adapted for use with suction-side cleaners, a float may be positioned within the head for improved buoyancy of the device. In such case the float may also have an opening to avoid inhibiting fluid communication between the tube and cartridge. The float alternatively may be formed integrally with the head, located outside the head, or otherwise positioned as desired respecting the remainder of the device. 
     When used with a suction-side cleaner, a device of the present invention is interposed in a pool between the cleaner and the inlet of a pump. Suction caused by action of the pump draws water from the automatic pool cleaner through the tube (including past the gap), from inlet to outlet. The suction additionally draws water from the pool up into the cartridge, where it contacts the purification media, and thence through the gap into the tube where it joins the water stream from the automatic pool cleaner for passage to the filtration system outside the pool. 
     When used with a pressure-side cleaner, alternatively, the device of the present invention is positioned in the pool between the cleaner and the outlet of the pump. Pressurized water exiting the pump passes through the inlet/outlet tube in two streams, one of which exits the outlet of the tube to power the automatic pool cleaner and the other of which travels through the secondary opening. This other stream then proceeds down through the cartridge (thus contacting the sanitizing media) and into the swimming pool. 
     It is therefore an object of the present invention to provide equipment and techniques for treating water within a (typically recreational) body, such as a pool, spa, or hot tub, through which water circulates. 
     It is also an object of the present invention to provide devices for purifying water useful in conjunction with an automatic swimming pool cleaner, whether suction- or pressure-side. 
     It is a further object of the present invention to provide equipment incorporating a head and a cartridge, at least the latter being adapted for placement in a pool intermediate an automatic swimming pool cleaner and either the inlet or the outlet of the filtration system of the pool. 
     It is another object of the present invention to provide systems in which the same cartridge may be utilized regardless of whether the associated automatic pool cleaner is a suction- or pressure-side cleaner. 
     It is an additional object of the present invention to provide reclosable or replaceable cartridges so as to permit disposal and replacement of the purification media contained therein. 
     Other objects, features, and advantages of the present invention will become apparent to those skilled in the art with reference to the remainder of the text and the drawings of this application. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a device of the present invention adapted especially for use with a suction-side automatic swimming pool cleaner. 
     FIG. 2 is an exploded perspective view of a device of the present invention adapted especially for use with a pressure-side automatic swimming pool cleaner. 
    
    
     DETAILED DESCRIPTION 
     FIGS. 1-2 illustrate an exemplary device  10  of the present invention. Device  10  may include head  14  as well as cartridge  18  in which water purification media  20  (shown conceptually) is placed. Media  20  may comprise pellets, foam, or any other suitable mechanism or item adapted to inhibit growth of, or kill, bacteria, algae, or any other undesirable material contained in water to be used recreationally by humans. Because the invention contemplates water flowing through cartridge  18 , it includes one or more of both (nominally) upper and lower slots  22  and  26 , respectively, intermediate which media  20  is positioned. Although constituents of media  20  may leach or be abraded into (or otherwise be carried with) the stream of water flowing through cartridge  18 , media  20  preferably is formed, sized, placed in a porous bag, or otherwise acted upon so that it generally is retained within the cartridge  18  rather than being able to escape in bulk through slots  22  or  26  (which need not necessarily be elongated but rather may be of any desired shape). 
     Also shown in FIG. 1 is optional float  30  and, in FIGS. 1-2, inlet/outlet tube  34 . Float  30  is particularly useful when device  10  is used with a suction-side cleaner, as it avoids excessive sinking of the device  10  within the pool by providing additional buoyancy. Float  30  usually is unnecessary when device  10  is used with a pressure-side cleaner, however, and thus is not shown in the exemplary device  10  of FIG.  2 . 
     Tube  34  provides the primary flow path through device  10  from the automatic swimming pool cleaner to the filtration system of the pool. Although referred to herein as a “tube” for convenience, tube  34  need not necessarily be wholly, or even partly, tubular in shape. Instead, any structure adapted to permit fluid flow therethrough may be acceptable in certain circumstances. Nonetheless, tube  34  preferably is tubular, with ends  38  and  42  adapted to connect to hoses conventionally used with automatic swimming pool cleaners. As shown in FIG. 2, ends  38  and  42  may have terminal rings or flanges  46  fitted therein (or integrally formed therewith or connected thereto) if useful for connection to hoses used typically with pressure-side swimming pool cleaners. Although not shown in FIG. 1, such flanges  46  might also be appropriately used with certain hoses connecting to suction-side cleaners. 
     Tube  34  preferably is molded as part of head  14 . Alternatively, tube  34  may be fitted within a corresponding opening through head  14 . In either event, tube  34  either has a secondary opening  50  (shown in dotted lines in FIG. 2) or is formed of sections  52 A and  52 B with a cavity or gap  52 C therebetween (see FIG. 1) within head  14  to allow fluid to communicate between the tube  34  and cartridge  18 . Float  30 , if present between tube  34  and cartridge  18 , likewise has an opening  54 —which can be aligned generally with gap  52 C—to continue the fluid flow path. When tube  34  is indeed tubular, float  30  may be shaped in some respects similar to a saddle to provide a recessed area  58  in which portions of sections  52 A and  52 B may fit. 
     In embodiments of device  10  consistent with FIGS. 1-2, cartridge  18  comprises (nominally) upper part  62  and (nominally) lower part  66 . Parts  62  and  66  are designed, if desired, to be assembled (to form cartridge  18 ), disassembled (when, for example, media  20  needs to be replaced), and reassembled (for further use after the replacement of media  20 ). Shown in FIGS.  1 — 2  are (one or more) clips  70  depending from the interior of upper part  62 , which clips  70  may snap into corresponding recesses  74  in the interior of lower part  66 . If such a snap-fit technique is employed, clips  70  can be sufficiently resilient to unlatch to disassemble parts  62  and  66 . However, those skilled in the art will recognize that numerous other techniques for fastening and unfastening parts  62  and  66  may be utilized consistent with the present invention. Alternatively, clips  70  can fix in place within recesses  74  (and not be removable therefrom), in which event cartridge  18  may be replaced in its entirety when the purification capability of media  20  is depleted. 
     Upper part  62 , furthermore, is illustrated as having exterior threads  78  intended to engage corresponding interior threads (not shown) of head  14 . Such engagement connects cartridge  18  to head  14  to provide device  10 ; it also at least partially seals cartridge  18  to head  14 . Again, however, those skilled in the relevant field will understand that other connectors and connecting methods may be used without exceeding the scope of the present invention. 
     FIGS. 1-2, finally, additionally illustrate optional wheel  82  which, if present, may be attached to head  14 . Wheel  82  includes information (such as a pointer or the months of the year) to facilitate determination of a consumer as to when to replace media  20  within cartridge  18 . Depending on the technique chosen to display the date-related information, wheel  82  may need to be detachable from head  14  for replacement or reprogramming when media  20  is replaced. 
     For use with a suction-side automatic swimming pool cleaner, device  10  is positioned so that at least slots  26  are below the water line of a swimming pool. A hose (or other suitable component) connects end  38  to the outlet of the automatic pool cleaner, while another hose (or other suitable component) connects end  42  to the filtration system of the pool and, indirectly, the inlet of a pump. As the pump is activated and suction induced, debris-laden water is drawn through the automatic pool cleaner and into the connecting hose. End  38 , functioning as an inlet, receives the debris-laden water and permits it to pass through tube  34  (including past gap  52 C) to end  42  (functioning as an outlet) and thence on to the pool filtration system. In this respect, tube  34  operates merely as a conduit between the connecting hoses. 
     However, suction caused by activating the pump and Venturi action associated with the flow through tube  34  also induce water to flow from the pool into cartridge  18  through slots  26 . This water, usually having less debris entrained therein than that passing through the automatic swimming pool cleaner, contacts purification media  20  within cartridge  18  (and thereby is treated chemically) before being withdrawn from cartridge  18  through slots  22 . The suction continues by drawing the treated water through both opening  54  of float  30  (if present) and gap  52 C, where it joins the water stream from the automatic pool cleaner. The joined streams thereafter exit tube  34  through end  42  and pass to the filtration system for filtering and subsequent recirculation in the pool. 
     As illustrated in FIGS. 1-2, slots  22  may be made smaller than slots  26 . Doing so causes slots  22  to govern the fluid flow rate through cartridge  18  when device  10  is used with a suction-side cleaner. Making slots  22  of lesser size than slots  26  thus reduces the amount of suction used to draw water through cartridge  18 , permitting the majority of the pressure reduction to remain available to power the suction-side automatic pool cleaner. When the suction-creating pump is not operating, the fact that slots  26  are larger allows greater exposure of pool water to media  20  through (in essence, its passively) soaking into cartridge  18 . 
     When device  10  is used with a pressure-side cleaner, filtered water exiting the filtration system of the pool passes into end  38 , through tube  34 , and out end  42  to the pressure-side cleaner. Such water is pressurized, however, and some of the filtered water is forced through secondary opening  50  (see FIG. 2) down through slots  22  into cartridge  18 . In cartridge  18  the filtered—and thus again relatively debris-free—water is treated by media  20  before being forced through slots  26  into the swimming pool. 
     Because device  10  typically has multiple slots  22 , secondary opening  50  likely provides the smallest aperture in this water path. Accordingly, in such cases when device  10  is used with a pressure-side pool cleaner, secondary opening  50  (rather than slots  22 ) governs the flow rate through cartridge  18 . As a consequence, appropriate sizing of secondary opening  50  will allow function of device  10  without significant detrimental effect on the operation of the automatic pool cleaner. 
     The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention.