Abstract:
Automatic swimming pool cleaners are detailed. The cleaners may employ filter bags with novel stiffeners to help retain their optimal debris-collection shapes in use. They additionally may include bags made of material having sanitizing properties or additives, allowing water sanitization to occur as water flows through the bags themselves. Cleaners described herein further may include discs having generally radial but non-linear slits to facilitate navigation in particular conditions and fix buoyant material within a collar by which a bag is attached to a body of the device.

Description:
FIELD OF THE INVENTION 
     This invention relates to automatic swimming pool cleaners including (but not limited to) pressure-side cleaners having any or all of innovative discs and bags, novel placement of flotation material, and water-sanitization capabilities. 
     BACKGROUND OF THE INVENTION 
     U.S. Pat. No. 4,351,077 to Hofmann illustrates one of numerous existing designs for automatic swimming pool cleaners. Cleaners such as that depicted in the Hofmann patent are configured for attachment, via a hose, to the inlet of an associated pump. They hence are commonly referred to as “suction-side” cleaners, as the inlet forms the “suction” side of the pump. When the pump operates, debris-laden water is drawn from the pool through the cleaner body (head) and hose to, typically, a filtration mechanism remote from the cleaner itself. 
     Many traditional suction-side cleaners include internal valves and external discs to effect movement of the cleaners within pools. As described in the Hoffman patent, for example, an internal flapper valve oscillates between two terminal positions within the fluid-flow path of the cleaner. The oscillation results, in use, to an intermittent cut-off flow through the head as the valve oscillates between its terminal positions and this in turn causes pulsations which result in longitudinal contractions and relaxations in the longitudinally resilient suction [hose] . . . . In consequence of these contractions and relaxations and a simultaneous reduction and increase of the force applied to hold the disc against the surface to be cleaned, a step by step movement of the head takes place over the surface to be cleaned. 
     See Hofmann, col. 3,11. 41-52 (numeral omitted). 
     Multiple discs have been designed to enhance cleaner performance in pools. U.S. Pat. No. 5,421,054 to Dawson, et al. and U.S. Pat. No. 5,418,995 to Rice, et al., illustrate annular discs having peripheral, upwardly-extending fins and generally circumferential slots, respectively. U.S. Pat. No. 4,530,125 to Hofmann details an annular disc with four equally-spaced, linear slits extending radially inward from the periphery toward the central aperture. U.S. Pat. No. 5,465,443 to Rice, et al. depicts yet other suction-side cleaner discs, including one having a series of generally radial, linear slits present solely in the rear section of the disc. This disc additionally accepts a cap similarly comprising rearwardly-positioned radial slits. 
     “Pressure-side” cleaners, by contrast, conventionally do not utilize annular discs to facilitate their movement within pools. These cleaners, which are connected (again typically via hoses) to outlets of associated pumps, instead use pressurized water flow to turn turbines, provide jet streams, or otherwise to effect their movement. One example of such a pressure-side cleaner in which a turbine drives wheels is shown in U.S. Pat. No. 3,936,899 to Henkin, et al. 
     Additionally unlike suction-side cleaners, pressure-side cleaners typically employ filtration mechanisms either within or proximate to their bodies. U.S. Pat. No. 5,930,856 to Van der Meyden, et al. illustrates a pressure-side cleaner with an internal screen-type filter for retaining debris, while the Henkin patent details such a cleaner with a filter in the form of a bag connected to the body. The Henkin patent further illustrates a float positioned externally of the body of the cleaner. 
     U.S. Pat. No. 5,802,653 to Roumagnac, finally, discloses a pressure-side cleaner incorporating a disc. The disc is indicated solely as being a “flange” or “flexible skirt,” however, without indication of its shape or structure. The Roumagnac patent additionally does not disclose including a float as part of a cleaning device, nor does it identify any stiffener or other support for its external debris receptacle. 
     Thus, although many versions of automatic pool cleaners have been designed, no cleaner currently includes a disc with generally radial non-linear slits. Likewise, no pressure-side cleaner incorporates a float into an interface between a filter bag and the body. Few stiffeners for bags presently exist, and, to applicants&#39; knowledge, no current cleaner is adapted to sanitize water flowing through a filter bag attached to the cleaner. Nevertheless, the disclosure of each of the Hofmann &#39;077 and &#39;125 patents, the Dawson patent, the Rice &#39;995 and &#39;443 patents, the Henkin patent, the Van der Meyden patent, and the Roumagnac patent is hereby incorporated herein in its entirety by this reference. 
     SUMMARY OF THE INVENTION 
     The present invention improves existing pool cleaner technology by developing features omitted from prior cleaner designs. Certain presently-preferred versions of the cleaners employ filter bags with novel stiffeners to help retain their optimal debris-collection shapes in use. These or other versions additionally may include bags made of material having sanitizing properties or additives, allowing water sanitization to occur as water flows through the bags themselves. Cleaners of the present invention additionally may include discs having generally radial but non-linear slits to facilitate navigation in particular conditions. 
     They further may fix the location of buoyant material within the cleaners relative to the positioning of the bags and the bodies. Indeed, in some versions, the buoyant material, typically foam, is placed within a collar by which a bag is attached to a body of the device. If the position of the buoyant material were not fixed in this manner, the material could move as the cleaner orientation changes, thereby changing the buoyancy characteristics of the cleaner as it moves within a pool (and particularly when it attempts to climb pool walls). 
     It thus is an optional, non-exclusive object of the present invention to provide innovative automatic swimming pool cleaners. 
     It is an additional optional, non-exclusive object of the present invention to provide pressure-side cleaners with novel filter bags. 
     It is another optional, non-exclusive object of the present invention to provide pressure-side cleaners employing annular discs to facilitate cleaner movement within pools. 
     It is, moreover, an optional, non-exclusive object of the present invention to provide cleaner discs having generally radial but non-linear slits. 
     It is a further optional, non-exclusive object of the present invention to provide cleaners with filter bags having novel stiffeners. 
     It is also an optional, non-exclusive object of the present invention to provide cleaners whose filter bags are made of, or include as additives, water-sanitizing material. 
     It is yet another optional, non-exclusive object of the present invention to provide cleaners including buoyant material whose position is fixed relative to certain other components of the cleaners. 
     It is an additional optional, non-exclusive object of the present invention to provide cleaners in which buoyant foam is incorporated into collars by which bags are attached to cleaner bodies. 
     Other objects, features, and advantages of the present invention will be apparent to those skilled in the relevant fields with reference to the remaining text and drawings of this application. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an exemplary automatic swimming pool cleaner of the present invention. 
         FIG. 2  is an elevational view of the cleaner of  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the cleaner of  FIG. 1  taken along line A-A of  FIG. 2 . 
         FIG. 4  is an exploded view of the cleaner of  FIG. 1 . 
         FIG. 5  is a partially cut-away view of certain components (including a bag, stiffener, and buoyant material) of the cleaner of  FIG. 1 . 
         FIG. 6  is a top plan view of a disc of the cleaner of  FIG. 1 . 
         FIG. 7  is a cross-sectional view of the disc of  FIG. 6  taken along line A-A of that figure. 
         FIG. 8  is a cross-sectional view of the disc of  FIG. 6  taken along line C-C of that figure. 
         FIG. 9  is a detail view of a portion of the disc shown in  FIG. 7 . 
         FIG. 10  is a perspective view of the underside of the disc of  FIG. 6 . 
         FIG. 11  is a detail view of a portion of the underside of the disc of  FIG. 6  showing, as darker areas, channels existing in the underside of the disc. 
     
    
    
     DETAILED DESCRIPTION 
     Detailed in  FIGS. 1-4  is an exemplary automatic swimming pool cleaner  10  of the present invention. Included as part of cleaner  10  may be any or all of head or body  14 , filter  18 , footpad  22 , and disc  26 . Cleaner  10  is designed beneficially for use submerged within a swimming pool, with pressurized water entering the pool being used for motive and debris-collection purposes. Cleaner  10  hence preferably is a pressure-side cleaner, although many aspects of the invention may be utilized for other cleaners or devices as appropriate or desired. 
     Comprising body  14  may be first inlet  30 , second inlet  34 , and first outlet  38 . First inlet  30  advantageously connects to a pump discharge opening, typically (although not necessarily) in the side wall of a pool. Such connection may occur directly or indirectly and using a hose, pipe, or other suitable means. Accordingly, first inlet  30  is adapted to receive pressurized water having exited a pump of a water-circulation system associated with the pool. 
     Second inlet  34 , by contrast, receives debris-laden water directly from the interior of the pool. In the version of cleaner  10  shown especially in  FIG. 3 , for example, the debris-laden water then travels (nominally) upward through (nominally) vertical tube  42  to first outlet  38 . From first outlet  38 , the debris-laden water enters filter  18  to remove most solid matter therefrom. 
     Additionally included as part of body  14  may be shell  46 , second outlet  50 , and a multi-sleeve structure  54 . Shell  46 , shown in  FIG. 4  as halves  46 A and  46 B that may be fitted together, need not necessarily be present in body  14 . If present, however, shell  46  beneficially may be used to seat structure  54  relative to second outlet  50 . 
     Second outlet  50  and structure  54  may function cooperatively as described in, for example, the Roumagnac patent. As indicated therein, sleeves of structure  54  may rotate, causing certain openings to align periodically, thereby temporarily altering a path of the pressurized water flowing within cleaner  10 . Each alteration causes an elastic pipe or hose connected to first inlet  30  to contract, effectively pulling cleaner  10  in the direction of the contraction in a step-wise fashion. 
     Again consistent with the Roumagnac patent, most pressurized water entering cleaner  10  via first inlet  30  is expelled through an internal nozzle upward into tube  42 . Venturi principles dictate that this jet of water will tend to evacuate the surrounding area, sucking debris-laden pool water into tube  42  through second inlet  34 . The evacuation additionally tends to force disc  26  against the surface of the pool to be cleaned. 
     As shown in  FIGS. 1-5 , filter  18  preferably is in the form of a bag  58  defined by mouth  62  and sealed edges  66 A-C. If present as bag  58 , filter  18  advantageously is a mesh, with spacing such that water may pass through the mesh while most entrained particulate matter may not. Those skilled in the relevant art will, however, recognize that filter  18  need not necessarily be in the form of a bag or, if a bag, need not necessarily be configured or function identically to bag  58 . 
     Connecting bag  58  to tube  42  may be collar  70 . Collar  70  may attach to body  14  in any manner permitting fluid communication between tube  42  and bag  58 . Preferably, however, collar  70  is snap-fitted directly onto tube  42  of body  14  in the vicinity of first outlet  38 . Collar  70  additionally receives mouth  62  of bag  58 , with clip  74  or any other suitable fastener fixing bag  58  in place. 
     Positioned along leading edge  66 A of bag  58  is stiffener  78 . Stiffener  78  preferably is configured as an elongated, curved rod as shown in  FIGS. 1-5 . If so configured, end  82  is the (nominally) forwardmost portion of stiffener  78 , with the stiffener  78  extending rearwardly to end  86 . The result is a lower profile for bag  58  than if stiffener  78  were linear. Stiffener  78  preferably is sewn into or otherwise attached within bag  58  along edge  66 A, although it could alternatively be attached to the exterior of bag  58  or at a location other than edge  66 A. 
     Whether or not curved, when located along edge  66 A, stiffener  78  nevertheless functions much like a mast during operation of cleaner  10 . Accordingly, bag  58  functions similar to a sail when cleaner  10  is in use. Cooperatively, stiffener  78  and water flow into mouth  62  serve to minimize possibility of collapse of bag  58 , thereby reducing likelihood of bag  58  being clogged prematurely. Consequently, bag  58  need not be clipped to any input hose or pipe to prevent its collapse. 
     As noted above, the mesh design of bag  58  allows mechanical filtration of water passing through the bag. If desired, however, bag  58  additionally may chemically filter water passing therethrough. Indeed, bag  58  may be formed of anti-microbial material or have anti-microbial material added thereto, one example of which is provided under the brand name MICROBAN® anti-microbial material available from Microban International, Ltd. Water contacting the anti-microbial material may be sanitized thereby as it passes through bag  58  back into a pool. 
     Positioned within collar  70  is buoyant (flotation) material  90 , depicted in  FIGS. 3-5  as an annular piece of foam. Material  90  need not be so shaped or positioned, however, and may comprise buoyant elements other than foam if desired. Preferably, however, material  90  is fixed within collar  70 , so that its position relative to body  14  does not change even if cleaner  10  changes its orientation within a pool. Such position fixing is especially advantageous when cleaner  10  climbs a side wall of a pool; in particular, as compared to cleaners in which flotation material is positioned within the filter bag (and thus can move as the bag moves or, because of its buoyancy, can cause the bag to move), cleaner  10  reduces the likelihood that bag  58  will undesirably tend to float to the surface of the pool as the cleaner  10  climbs a wall. 
       FIGS. 6-11  illustrate aspects of disc  26  of the present invention. Disc  26  includes upper surface  94  and underside  98 . As depicted, disc  26  is generally annular, with generally circular, chamfered periphery  102  and defining circular central aperture  106 . Although applicants presently prefer such annular shape for disc  26 , it need not necessarily be so shaped. Disc  26  is adapted to be received by body  14  (see, e.g.,  FIG. 3 ) and to abut footpad  22 . (Alternatively, disc  26  may be received by the footpad  22 .) 
     Incorporated into disc  26  are series of through holes  110  and multiple curved slits  114 . Holes  110  function similar to the immediate apertures of the Rice &#39;995 patent. Rather than being sized identically, however, holes  110  preferably are of differing diameters. Indeed, most preferably holes  110  increase in size from periphery  102  toward central aperture  106 . Holes  110  need not necessarily be configured in this manner, however, nor need they be circular in shape. 
     Slits  114  divide peripheral portion  118  of disc  26  into multiple fingers  122  containing through holes  110 . Unlike the rear-section-only slits of the Rice &#39;443 patent, slits  114  may be present throughout the circumference of disc  26 . Consequently, even if disc  26  rotates some in use, no misorientation of fingers  122  will occur. Likewise, if suction force is lost for any particular finger  122  (as, for example, when such finger  122  encounters an object protruding outward from the surface to be cleaned), suction force for most or all remaining fingers  122  should be unaffected. 
     Significantly, moreover, slits  114  preferably are not linear but rather are curved. By curving slits  114 , the area of suction break possible over linear slits for the same radial distance inward from periphery  102  is increased. Curving slits  114  additionally helps a given finger  122  to resist movement that otherwise might cause it laterally to overlap an adjacent finger  122 . 
     Depicted especially in  FIGS. 10-11  is underside  98  of disc  26 . As shown in these figures, underside  98  additionally may include generally radial, curved channels  126 , each communicating with annular channel  130  circumscribing central aperture  102 . Channels  126  need not necessarily be curved, however, nor, if curved, need they necessarily be curved similar to the curvature of slits  114 . Likewise, channel  130  need not necessarily be annular. 
     Moreover, although ten channels  126  are detailed in  FIG. 10 , fewer or greater numbers of channels  126  may be present instead. Preferably, however, channels  126  and  130  are formed as shown in  FIGS. 10-11 , with channels  126  alternating in fingers  122 . Also advantageously, holes  110  are positioned so that at least some sets communicate with channels  126 . Together, holes  110 , channels  126 , and channel  130  help manage suction pressure of disc  26  against a surface to be cleaned and enhance water flow into second inlet  34  of body  14 . 
     The foregoing is provided for purposes of illustrating, explaining, and describing exemplary embodiments and certain benefits of the present invention. Modifications and adaptations to the illustrated and described embodiments will be apparent to those skilled in the relevant art and may be made without departing from the scope or spirit of the invention.