Abstract:
An debris-capturing apparatus having a fluid-pervious wall, an attachment portion attachable to the outflow port of a pressure-cleaner device, and a collapsible inflow tube that is substantially opened and made erect by the inflow of fluid but otherwise axially collapsed and thereby closed so as to block reverse flow of debris through the outflow port. The erected inflow tube preferably has cross-sectional flow areas along its entire length approximating the cross-sectional flow area of the outflow port. The debris-capturing apparatus is preferably integrally formed such that the inflow tube is a turned-in extension of the attachment portion.

Description:
FIELD OF THE INVENTION 
     The present invention relates to swimming pool cleaners and, more particularly, to automatic cleaners that move along the underwater surface of a swimming pool. Still more specifically, the invention relates to devices designed to collect and capture the debris dislodged during the sweep of a pool through the operation of such cleaners. 
     BACKGROUND OF THE INVENTION 
     Automatic swimming pool cleaners of the type that move or sweep along the underwater surface of a residential or commercial swimming pool have become popular for dislodging and collecting debris and sediment from the floor of the pool. Cleaning devices of this type include several where a flow of water under pressure is harnessed to provide not only power for the forward motion of the cleaner but also the means by which the debris is drawn through hydraulic suction into some manner of debris-capturing apparatus. See, for example, the turbine-driven automatic swimming pool pressure cleaner shown and described in commonly-owned PCT International Publication No. WO 01/92663, entitled “Swimming Pool Pressure Cleaner with Internal Steering Mechanism,” of Poolvergnuegen of Santa Rosa, Calif. Typically, the pressurized water supply for such automatic pool cleaners is provided by a remote pump. 
     A typical debris-capturing apparatus for such devices is referred to as a pressure-cleaner bag. Such bags are made from a flexible porous fabric that allows water drawn upward from the floor of the pool into the bag to pass through it, thus trapping any and all debris entering the bag with the water. Moreover, each of these bags has an attachment portion that forms an opening into the bag and provides sleeved attachment to an outflow port of the pool cleaner. 
     In many pressure-cleaner bags, however, debris will tend to collect inside the bag in the area of the attachment to the outflow port. This poses a number of problems to the effective operation of the cleaner. The accumulation of debris near the mouth of the outflow port creates an obstruction to the free flow of water through the port. It also allows the debris to re-enter the swimming pool by falling back through the outflow port when the cleaner is turned off. In addition, some spillage of debris is inevitable when the bag is removed from the cleaner due to the absence of any means of closing off the opening into the bag. 
     While some improvements have been made in the past in pressure-cleaner bags to address certain of these concerns, past efforts have involved certain other disadvantages. For example, certain prior devices have involved complex design that may add expense in the manufacture of pressure-cleaner bags, limit the ability to reuse them efficiently over time, and even somewhat restrict or limit the inflow of water and debris. One such prior device is disclosed in U.S. Pat. No. 4,856,913 (Campbell). 
     This invention addresses such problems and shortcomings. 
     OBJECTS OF THE INVENTION 
     It is a primary object of this invention to provide an improved debris-capturing apparatus overcoming some of the problems and shortcomings of the prior art, including those mentioned above. 
     Another object of this invention is to provide an improved swimming pool pressure-cleaner bag which stops return flow of debris and yet is simple to manufacture and highly reliable in operation. 
     Another object is to provide an improved swimming pool pressure-cleaner bag which stops return flow of debris and yet allows substantially unrestricted inflow of water and debris. 
     Another object is to provide an improved swimming pool pressure-cleaner bag which stops return flow of debris and operates reliably over an extended period of time. 
     Still another object of the invention is to provide an improved swimming pool pressure-cleaner bag that is easy and inexpensive to manufacture, easy to ship and store, and easy to install and maintain. 
     These and other objects of the invention will be apparent from the following descriptions and from the drawings. 
     SUMMARY OF THE INVENTION 
     This invention is an improvement in a debris-capturing apparatus of the type including (a) a fluid-pervious wall forming a cavity, (b) an attachment portion forming an opening into the cavity and having an annular lowermost edge where it is attached to the outflow port of a pressure-cleaner device, and (c) an inflow tube inside the cavity that is substantially opened by the inflow of fluid from the outflow port but is otherwise closed to block reverse flow of debris through that port. 
     In the improvement of this invention, the inflow tube has an annular proximal edge secured to the attachment portion at its lowermost edge and the tube is made of a material whereby it is substantially erect along the flow axis defined by the inflow of fluid but is otherwise collapsed axially so as-to block any reverse flow of debris out of the cavity. When the pressure-cleaner device is operating with the apparatus attached, the pressure from the flow of fluid entering the attachment portion expands the inflow tube so that it achieves an erect configuration, allowing the fluid to enter the cavity. When the pressure cleaner is not operational, the absence of pressure from an inflow of fluid causes the tube to collapse on itself. With collapse, the inflow tube folds over onto itself to form a flaccid mound of material in a random fashion covering the opening to the outflow port and thereby blocking any flow of debris out of the cavity into the pressure-cleaner. This collapse, because it is along the axis of what was the erect inflow tube and is generally in the direction of the proximal edge of such tube, can be described as “axial collapse.” 
     In the debris-capturing apparatus of the present invention, the erected inflow tube has preferably cross-sectional flow areas along its entire length approximating the cross-sectional flow area of the outflow port of the pressure-cleaner device, although other shapes are possible. This preferred embodiment minimizes any outflow restriction through the inflow tube. 
     In a highly preferred embodiment of the present invention, the inflow tube is made of a fluid-pervious material. Most preferably, the inflow tube is integrally formed with the attachment portion. The term “integrally formed” means that adjacent portions of the apparatus (bag) are formed together, i.e. without any seam or other formed juncture where they meet. In a more specific embodiment, the fluid-pervious wall, the attachment portion and the inflow tube are all integrally formed and constitute a pressure-cleaner bag. This allows the inflow tube to be a turned-in extension of the attachment portion. 
     In certain preferred embodiments of the present invention, the pressure-cleaner device is a swimming pool pressure cleaner. In such embodiments, it is highly preferred that the fluid-pervious wall, the attachment portion and the inflow tube constitute a pressure-cleaner bag formed from a unitary piece. The term “unitary piece” refers to portions which are integrally formed. 
     Another highly preferred embodiment has a band attached at its opposite ends to the top portion of the fluid-pervious wall. This band secures the debris-capturing apparatus with respect to a pressure hose attached to the pressure-cleaner device to allow the fluid-pervious wall to remain substantially upright. While cords and belts of various shapes and materials are possible, a most highly preferred choice for the band is a length of rope. 
     In another alternative embodiment, the invention is an improved swimming pool pressure-cleaner bag comprising (a) a fluid-pervious wall forming a cavity, (b) an attachment portion forming an inflow opening and having an annular lower edge, and (c) an erectible-collapsible inflow tube portion inside the cavity. The inflow tube portion includes an annular proximal edge secured to the attachment portion at and around the annular lower edge and a distal end free to move within the cavity. The inflow tube portion also is made from a material chosen so that it remains substantially erect along a flow axis when fluid is entering the bag but otherwise collapses axially to block any reverse flow and thereby capture and collect debris. 
     In such an embodiment, it is preferred that the pressure-cleaner bag be a unitary piece, the inflow tube portion being a turned-in extension of the attachment portion. Most preferably, the erected inflow tube portion has a cross-sectional flow area along its entire length approximating the cross-sectional flow area of the outflow port of the pressure-cleaner device to which the bag is attached. It is also highly preferred that the bag include a band that has its opposite ends attached to the top portion of the fluid-pervious wall so that the fluid-pervious wall can remain substantially upright by securing itself, by means of the band, to the pressure hose attached to the inflow port of the pressure-cleaner device. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of an improved swimming pool pressure-cleaner bag of the present invention mounted on a swimming pool pressure cleaner including a partial cut-out showing internal bag components; 
     FIG. 2 is a side view of the swimming pool pressure-cleaner bag in FIG. 1 including a partial cut-out showing internal bag components; 
     FIG. 3 is a side view an exemplary swimming pool pressure-cleaner bag according to the present invention showing the inflow tube as a turned-out extension and integral with the attachment portion of the bag; 
     FIG. 4 is a side constructional view of the swimming pool pressure-cleaner bag of the present invention including a partial cut-out showing the inflow tube in a status of collapse prior to the swimming pool pressure cleaner being operational; 
     FIG. 5 is a side constructional view of the swimming pool pressure-cleaner bag of FIG. 4 including a partial cut-out showing the status of the inflow tube when fluid pressure is present at the outflow port after the swimming pool pressure cleaner is operational; 
     FIG. 6 is a side constructional view of the swimming pool pressure-cleaner bag of FIG. 5 including a partial cut-out showing the status of the inflow tube immediately after fluid pressure entering the bag from the outflow port stops; 
     FIG. 7 is a side constructional view of the swimming pool pressure-cleaner bag of FIG. 6 including a partial cut-out showing the status of the inflow tube minutes after fluid pressure entering the bag from the outflow port has stopped. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 illustrates an improved swimming pool pressure-cleaner bag  10  having a fluid-pervious wall  12 , an attachment portion  14 , and a collapsible inflow tube  16 . The wall  12  forms a cavity  18  that accommodates the inflow tube  16 . The bag  10  is shown removably attached to a swimming pool pressure cleaner  20  at an outflow port  22  by means of the attachment portion  14 . During operation of the swimming pool pressure cleaner  20  with the bag  10  so attached, a flow of fluid, usually water, is received by the bag  10  through an inflow opening  24  located at the lowermost edge  26  of the attachment portion  14 . The water carries debris  25  such as leaves and twigs that is drawn from the surface being cleaned. 
     The wall  12 , attachment portion  14  and inflow tube  16  are each made from a flexible, open-mesh material such as nylon that allows water to pass through it but not any of the debris. The size of the mesh chosen will be based on the size of the debris particle sought to be collected. 
     As illustrated in FIG. 2, the inflow tube  16  has an annular proximal edge  28  that is secured to the attachment portion  14  at and around the lowermost edge  26 . The first side edge  30  of the wall  12  forms a discharge opening  32  that is held closed by velcro-type fastener strips  33  sewn onto the wall  12  along the first side edge  30 . The fastener strips  33  can be easily opened after operation of the swimming pool pressure cleaner  20  to empty debris from the bag  10  without disengaging it from the pressure cleaner  20 . After removing the debris, the discharge opening can be quickly closed again by re-engaging the fastener strips  33  in preparation for later debris collection. 
     As seen in FIG. 1, the bag  10  is also provided with a band  34  attached at its opposite ends  35  to the top portion  36  of the wall  12 . A pressure hose  38  that attaches to the inflow port  40  of the swimming pool pressure cleaner  20  is passed between the band  34  and the wall  12  so that the wall  12  remains substantially upright during operation of the swimming pool pressure cleaner  20 . While the choices in material with which to construct the band  34  will be apparent to those of ordinary skill in the art, a preferred selection is a length of rope. The band  34 , by keeping the wall  12  of the bag  10  substantially erect, prevents the bag  10  from shifting to one side of the swimming pool pressure cleaner  20  or the other as the cavity  18  fills with debris and thereby interfere with efficient operation of the pressure cleaner  20 . 
     As illustrated in FIG. 3, in a highly preferred embodiment of this invention, the wall  12 , attachment portion  14 , and inflow tube  16  are not separate members but integral. The bag  10  is thereby a unitary piece with no points or lines of separation between the wall  12 , attachment portion  14 , and inflow tube  16 . The bag  10  is constructed from a single piece of porous material cut to the desired shape that is folded over at the second side edge  42  and then sewn together along the top edge  43  and the third side edge  44 . Alternatively, the bag  10  is formed from two pieces of porous material sized to be of equivalent, conforming shape that are also sewn together at edges  43  and  44  as well as at the second side edge  42 . 
     In this embodiment, the inflow tube  16  is a turned-out extension of the attachment portion  14 . This portion of the bag  10  constituting the inflow tube  16  is then folded into itself up to the folding line  46  so that the tube distal edge  48  extends into and opens inside the cavity  18  as shown in FIG.  1 . After the inflow tube  16  is folded inside the bag  10 , the opening then formed at the folding line  46  becomes the inflow opening  24  where the attachment portion  14  is mounted onto the outflow port  22  of the swimming pool pressure cleaner  20 . 
     The swimming pool pressure-cleaner bag  10  of this invention provides significant improvements in its operation and use over other debris bags. This is illustrated by FIGS. 4-7. The bag  10  is shown installed upon the outflow port  22  of a swimming pool pressure cleaner  20  (not shown). The inflow opening  24  (not shown) is placed over the port  22  and locked in position by mounting rings  50 . Prior to use of the bag  10  for debris collection through activation of the swimming pool pressure cleaner  20 , as shown in FIG. 4, the inflow tube  16  resides inside the cavity  18  of the bag  10  in a flaccid, collapsed state. The condition of the inflow tube  16  is such that it rests over the outflow port opening  52 , blocking off the opening  52  so that there is little flow other than water into or out of the cavity  18 . 
     As seen in FIG. 5, when the swimming pool pressure cleaner  20  is in operation, water and debris  25  are forced upward through the outflow port  22  into the bag  10  in the direction depicted by arrow  54 . The pressure of this flow expands the inflow tube  16  so that it takes on the erect configuration illustrated. The symmetrical construction of the inflow tube  16  is such that, when erected, the tube takes on a cylindrical configuration. As a result, the flow across cross-sectional areas along its entire length approximates the cross-sectional flow area at the opening  52  of the outflow port  22 . This aspect of the inflow tube  16  minimizes any restriction or diversion in the flow entering the bag  10 . 
     As shown in FIG. 6, the inflow tube  16  collapses in upon itself when the swimming pool pressure cleaner  20  is turned off. From the loss of pressure due to the absence of flow entering the tube  16 , the direction of this collapse is opposite to the direction of the flow and therefore in the direction of the outflow port  22  along a line parallel to the axis of the tube  16  in its cylindrical state. With each such collapse, the inflow tube  16  returns to being a flaccid mound of porous material and arrives there in a generally random fashion. Each collapse leaves the material comprising the inflow tube  16  covering the outflow port opening  52  so as to block the flow of any debris  25  out of the bag  10  and into the swimming pool pressure cleaner  20  as seen in FIG.  7 . 
     While the principles of this invention have been described in connection with specific embodiments, it should be understood clearly that these descriptions are made only by way of example and are not intended to limit the scope of the invention.