Abstract:
An apparatus for skimming floating debris from an enclosed vessel of water wherein a circular current of water occurs, said apparatus comprising a frame defining an inlet portion positioned upstream and an outlet portion covered with netting positioned downstream. A collection area, also covered with netting and located at one end of the inlet portion, extends upstream from and with its open end perpendicular to the inlet portion so that the leading edge of the collection area sufficiently impedes the current along its permeable leading edge. This impediment induces a lateral current internal to the apparatus which causes a substantial portion of the floating debris entering the apparatus to be accumulated in the collection area out of the main flow of the current, rather than accumulating at the netting-covered outlet portion of the apparatus. This lateral collection area with its accompanying lateral current flow improves the ability of the apparatus to prevent debris from leaving the apparatus once captured.

Description:
[0001]    This Continuation-in-Part patent application is copending with and claims priority of U.S. patent application Ser. No. 09/694,043, as filed on Oct. 20, 2000, entitled “Swimming Pool Skimming Apparatus.” 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The current invention relates to the field of passive devices for the removal of floating waste from the surface of a liquid, and particularly to an improved, stationary apparatus for collecting floating debris in swimming pools having a circulatory current therein.  
           [0003]    There are numerous instances in which impurities or waste must be removed from the surface of a large body of liquid in order to maintain the purity of the liquid or to prevent contamination. Numerous commercial industrial processes, e.g. in the areas of beer making, sanitation systems, water treatment systems, chemical plants, or the food industry, are characterized by the presence of floating debris which is most economically removed by skimming the debris from the open surface of a liquid. In the domestic area, this requirement of debris removal from large bodies of liquid is most often found in swimming pools.  
           [0004]    Cleaning a swimming pool of debris is a common problem among pool owners. Such debris may enter swimming pools from many different sources. Wind and rain carry falling leaves, insects, dust, twigs and other objects onto the surface of the water in the pool where it may float for a period of time before sinking to the bottom. It is desirable to remove such debris before it becomes waterlogged and sinks to the bottom of the swimming pool, since the cleaning of bottom-resident debris by means of vacuum devices is labor intensive and costly.  
           [0005]    The prior art is replete with devices for skimming floating debris. Most such devices have a frame and netting construction. Handheld devices rely on human action to sweep the skimmer along the pool&#39;s surface to entrap floating debris, while passive devices are fixed along the edge of the pool and rely upon circular around the perimeter of the pool which are produced by the water jets of the pool filtration pump. These currents may be further enhanced by the Coriolis effect, which in the Northern Hemisphere is manifested by a tendency for objects moving in a straight line to move right, or clockwise. These passive devices are partially submerged in a pool with the inlet or water intake leading to a collection area. The inlet faces into the circulating water current, which flows through the device and exits through an outlet Debris is caught in the netting at the collection area, which is generally colocated with the outlet.  
           [0006]    For example, U.S. Pat. No. 5,849,184 discloses a device having an elongated inlet portion and a similarly elongated collection portion extending the width of the device, the inlet portion being positioned perpendicular to the flow of water.  
           [0007]    U.S. Pat. No. 4,089,074 discloses a triangular-shaped frame supporting a net with the inlet side of the triangle perpendicular to the flow of water and a collection area at the apex opposing the inlet side The current flows through the inlet portion and out through the collection portion, which collects debris in the main current flow.  
           [0008]    U.S. Pat. No. 5,264,122 discloses a floating stationary pool cleaner having a collection portion and an inlet portion but with integral water jets directing the floating debris into the inlet portion As with U.S. Pat. No. 4,089,074, the current flows through the inlet portion and out through the collection portion, which collects debris in the main current flow.  
           [0009]    U.S. Pat. No. 5,173,181 discloses an apparatus for positioning the detachable strainer from a manual pool scoop in an orientation perpendicular to the flow of the water in the pool, by means of a bracket attached to the pool&#39;s side. It has an inlet and collection portion as well.  
           [0010]    U.S. Pat. No. 5,279,728 discloses a basket or collection portion to receive debris from the circular flow in a pool. A tube and nozzle arrangement directs a forced flow of water through the basket portion, thus, presumably creating a circular current within the pool.  
           [0011]    U.S. Pat. No. 5,288,414 discloses another supporting device for a collection portion, in which the collection portion for skimming debris is supported by a support member attached to the side of the pool and a float around the neck of the support member.  
           [0012]    U.S. Pat. No. 5,759,388 discloses yet another stationary skimming device floating on the surface of the pool, having an inlet portion perpendicular to the flow of water and a collection portion at the opposing end, similar to that of U.S. Pat. No. 4,089,074.  
           [0013]    U.S. Pat. No. 5,911,878 discloses another passive pool skimmer with an elongated inlet portion and an outlet portion of roughly the same extent. It is non-rigidly secured to the side of the pool and is configured so that it does not present a hazard to swimmers.  
           [0014]    However, all such pool skimmers share the same problem, namely, that debris has a tendency to float out of the skimmer collection area when a certain amount of debris is collected; the debris can thus reenter the swimming pool where it either sinks to the bottom or else is collected again by the skimmer. This phenomenon has been observed to a greater or lesser extent in all such pool skimmers.  
           [0015]    This observed phenomenon is believed to be caused by the following actions The general circular pool current brings debris into the skimmer collection area and flows on through the netting collecting the debris. The current as it flows through the skimmer tends to keep the debris against the netting comprising the outlet portion. As the debris accumulates against the netting, the current flowing through the skimmer from its inlet to its outlet portions is reduced and the force keeping the debris against the netting of the outlet portion is lessened. As the current through the skimmer becomes weaker, the force keeping the debris against the netting of the outlet portion is weakened, thus allowing the trapped debris to float forward towards the inlet portion against the current Eventually the debris escapes the skimmer and is reintroduced into the swimming pool. It is also observed that the netting itself presents resistance to the swimming pool current; this resistance can be increased by using a finer mesh netting or some other permeable material, or decreased by using a coarser mesh. The accumulation of debris at the outlet portion forces pool owners to frequently clean the outlet/collection area in order to keep the circulatory pool current path clear and unimpeded. If the debris could be removed from the collection area before it could accumulate and impede water flow out the outlet area, then the skimmer could operate more efficiently for longer periods.  
           [0016]    In prior art, cleaning the pool skimmer is an tedious task. Most devices use a form of netting as the filter means. The advantage of using a netting for snagging and holding debris also serves as a disadvantage in the cleaning process. Removing the debris from the netting while the netting is attached to the device often is awkward and difficult.  
           [0017]    Thus, it can be seen that there is a need for a pool skimmer which effectively traps increased amounts of debris without allowing the trapped debris to be reintroduced into the swimming pool after capture. The skimmer should also be easily cleaned.  
         DISCLOSURE OF THE INVENTION  
         [0018]    It is thus an object of this invention to more efficiently collect debris than heretofore.  
           [0019]    It is a further object of this invention to collect debris by altering the circulatory current through a mesh resistance means on the water inlet area of the pool skimmer.  
           [0020]    It is a further object of this invention to provide a removable mesh filter to improve the cleaning and removal of debris.  
           [0021]    It is a further object of this invention to provide a means for collecting floating debris in such a way as to prevent the collected floating debris from inhibiting the current flow therethrough, and thus provide increased capacity and longer intervals between cleaning.  
           [0022]    It is a further object of this invention to provide a commercially viable means for skimming unwanted material from the surface of any vessel containing a liquid exhibiting a current.  
           [0023]    The invention resides not in any one of these features, per se, but rather in the particular combination of all of the herein disclosed and claimed. It is distinguished from the prior art in this particular combination of all of its structures for the functions specified. These and other objects of the invention may be more clearly seen from the detailed description of the preferred embodiment which follows.  
         SUMMARY OF THE INVENTION  
         [0024]    The present invention consists of a material, such as a net, sieve, or porous ceramic material, supported by a longitudinal frame having a rectangular inlet positioned in a vessel containing a viscous liquid, so that a current urged to flow around the perimeter of the vessel containing the liquid directs debris through the inlet to be caught by the permeable material In addition, the invention features a collection means with an opening, as for example a basket or some other enclosed volume, positioned at one end of the device and including a portion of the inlet but wherein the opening of the collection means is parallel to the current flow through the inlet The collection means is located upstream of the main inlet area and also covered with a material which may be permeable, semi-permeable, or impermeable, depending upon the nature of the liquid contained within the vessel. An unexpected result is observed in this arrangement. The positioning of a collection means upstream of the inlet portion of the device creates an observable secondary cross current flowing across the main current and through the liquid surface area within the collection means, the area immediately upstream of the inlet, and the main portion of the longitudinal frame. This secondary current which is induced by the resistance of the leading edge of the collection means opening and the material on the leading edge of the collection means tends to sweep debris from the main portion of the longitudinal frame and keeps it clear of debris which might inhibit free flow of liquid therethrough. A majority of the floating debris is thus captured within the collection means where it remains until it is removed from the apparatus or until it becomes saturated with the liquid upon which it floats, in which case it sinks to be captured in the portion of the collection means which extends below the surface of the liquid. In this manner, the invention is able to capture increased amounts of debris without clogging, and this increased time results in greater time between cleaning of the apparatus. This apparatus may be used in both commercial and domestic applications.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]    [0025]FIG. 1 shows a full three dimensional isometric view of a pool skimmer.  
         [0026]    [0026]FIG. 2 presents an overhead view of a pool skimmer as it is positioned within a swimming pool.  
         [0027]    [0027]FIG. 3 presents a top view of the invention to show how it functions in the presence of a current induced within the liquid within which it is partially submerged.  
         [0028]    [0028]FIG. 4 presents another embodiment of the invention to illustrate an alternative means for positioning the invention within a vessel and an alternative manufacturing method which embodies the principles of the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0029]    The simplest embodiment of the invention is given below in order to promote understanding of the principles involved in its use. Referring to FIG. 1 which gives a front perspective view of an embodiment of the invention which is directed towards domestic use, a pool skimmer  20  is shown generally having a proximal end  22  for stationary connection (not shown) with the edge of a swimming pool and a distal end  24  projecting into the interior of the swimming pool. Skimmer  20  is formed of a frame  30  constructed of any light material which can be formed into a frame to support netting.  
         [0030]    The material used for this embodiment and shown in the drawings consists of polyvinyl chloride tubing connected by T- and X-couplings, as is commonly found in swimming pool equipment. Other materials contemplated for this application would be fiberglass or extruded plastic. For swimming pool skimmers, the requirement for a frame is that it be resistant to water corrosion, light, and easily maintained by the owner. As such, frame  30  may be constructed in such a way, as shown, to facilitate easy assembly by untrained personnel or to promote compact packaging. However, frame  30  could also be constructed of continuous extruded and formed material which is held together during use by pins, screws, bolts, or any other semi-permanent connection means which holds the frame in a rigid shape, if disassembly is a goal. Frame  30  could also be assembled with more permanent connection means such as glue, welding, rivets, or integral casting, if more permanent and durable construction is a goal.  
         [0031]    The netting which is referenced in the description of this embodiment may be composed of any permeable material which allows a current of water to flow therethrough; however, a plastic or nylon netting material with a suitable mesh to entrap small particles of debris commonly found around the typical home is typically used. It should be noted that in other commercial processes, additional factors may be present which dictate the choice of netting material, for example, the resistance of the netting material to corrosion by the liquid contained within the vessel, the permeability of the netting with relation to the viscosity of the liquid, the force of current flow which may dictate a stronger netting material, etc.  
         [0032]    In the description that follows, the forward direction is considered to be a direction against the current and a rear direction is considered to be with the current.  
         [0033]    In the embodiment described in FIG. 1, Frame  30  is comprised of an upper frame member  40  and a lower frame member  50 , both extending longitudinally between the proximal end  22  and the distal end  24 . Frame members  40 ,  50  are held in constant spaced relation by distal vertical member  80  and proximal vertical member  85 . Vertical members  80 ,  85  are connected to the ends of frame members  40 ,  50  by L-couplings  107  to form a generally rectangular structure. Rear ribs  60   a ,  60   b ,  60   c , and  60   d  are spaced along the rear side of frame members  40 ,  50  and between vertical members  80 ,  85 . Rear ribs  60   c ,  60   d  are positioned towards the proximal end  22  of frame  20 , with the first ends of rear ribs  60   c  and  60   d  are connected to upper frame member  40  by a standard T-coupling  100  and the second ends of said ribs are connected to lower frame member  50  by a standard T-coupling  100  Rear ribs  60   a ,  60   b  are positioned towards the distal end  24  of frame  20  Front ribs  70   a  and  70   b  are spaced distally along the same side of frame members  40 ,  50  and oppose rear ribs  60   a  and  60   b , respectively. The first ends of ribs  60   a ,  70   a  and  60   b ,  70   b  are each connected to upper frame member  40  by a standard X-coupling  105  and the second ends of ribs  60   a ,  70   a  and  60   b ,  70   b  are connected to lower frame member  50  by a standard X-coupling  105 .  
         [0034]    Conceptually, the skimmer structure can be described as a frame to which is connected a side-mounted collection basket consisting of front ribs  70   a ,  70   b  and rear ribs  60   a ,  60   b , interconnected by a portion of frame members  40 ,  50  and vertical frame member  80 , the open face of which basket is defined by ribs  60   b ,  70   b  Alternatively, the skimmer structure can be described as a net structure consisting of a netting supported by a frame consisting of rear mounted ribs  60   a - d , upper and lower horizontal members  40 ,  50 , and vertical members  80 ,  85 , and having a collection scoop mounted at one end of the inlet portion and consisting of the forward mounted frame comprising ribs  70   a ,  70   b.    
         [0035]    Skimmer  20  is rigidly attached to a support (not shown) on the side of the swimming by means of proximal horizontal support member  110  and a support means  111 . Any such support means is contemplated, such as by clamps, screws, rings, and the like, wherein the support means rigidly suspends skimmer  20  so that it is half immersed longitudinally beneath the surface of the swimming pool. Optionally, float  108  may be connected to distal end  24  for floating support of skimmer  20 , such connection being accomplished by means of distal horizontal support member  109  attached to an L-coupling  100  along vertical frame member  80 , so as to reduce the supporting requirements for support means  111 .  
         [0036]    Frame  30  supports netting having a fine mesh suitably sized to allow water to pass through but to restrict most small particles of debris. A rear netting portion  150  of generally rectangular shape is attached along the length of upper frame member  40  and is wrapped around rear ribs  60   a -d to attach along the length of lower frame member  50  attachment may be accomplished by any suitable means, and the preferred manner of attachment is by a hook and loop arrangement commonly known to the industry. A front netting portion  155 , also of generally rectangular shape, is attached along upper frame member  40  between front ribs  70   a ,  70   b  and is wrapped around rear ribs  70   a ,  70   b  to attach along lower frame member  50  between front ribs  70   a ,  70   b . A distal netting portion extends over distal end  24  of pool skimmer  20 , attaching to the distal edges of front netting portion  155  and rear netting portion  150 , conceptually forming a collection basket. A proximal netting portion  170  extends over proximal end  24  of pool skimmer  20 , attaching to the proximal edge of rear netting portion  150 . Note that although the netting covering skimmer  20  has been described as four individual portions, the actual construction of the netting may be as a single piece cut appropriately or as multiple pieces which functionally cover the frame as described.  
         [0037]    The rectangular area defined by upper frame member  40  and lower frame member  50  and between rear ribs  60   b  and  60   d  define an inlet portion  115  which is unobstructed by netting. The area comprising the rear netting portion  150  is defined as the outlet portion  140  The collection area comprises the netting portion forming a conceptual basket on distal end  24  of skimmer  20 , namely, the area within distal netting portion  160 , forward netting portion  155 , and rear netting portion  150 .  
         [0038]    In another variant of the embodiment as described above is shown FIG. 4, where the frame and netting configuration may be constructed of a series of panels  300 , which are generally rectangular or square, having panel having a rigid frame into which the netting is permanently molded. Two of such panels are connected along their edges and the third panel is connected to a side of one of the two panels which is opposite the connected side, thus forming a C configuration. A plurality of such C configured panels are connected in parallel along their free edges to form a scoop arrangement. To each end of the scoop is attached another panel  301 ,  302  to form an enclosed scoop with an inlet area  303 . At one end of the inlet area, another C configuration  304  is attached with its opening opposing the inlet area and enclosed with another panel  305  on its end which is coincident with a previously enclosed scoop end, thus forming the collection area. All panels are connected by a connection means as described previously.  
         [0039]    The generally rectangular configuration of the panels allows a support means to be configured to the apparatus which will allow the apparatus to easily rise and fall with the level of the liquid while maintaining a horizontal attitude. A pool support means is rigidly attached to the edge of the vessel by means of connection points  316 , from which extend two horizontal support bars  314 ,  315  which terminate with two horizontally oriented rings  312 ,  313  which are permanently attached to support bars  314 ,  315 . The rings  312 ,  313  loosely encircle two U-shaped vertical support bars  310 ,  311  attached to the edges of end panel  301 . A float  317  is attached to the distal end of the apparatus to maintain its orientation with the surface of the liquid and another float (not shown) is optionally connected at the proximal end for similar reasons. It can thus be seen that the apparatus can be positioned perpendicular to the current flow by the arrangement while allowing the apparatus to rise and fall with the level of the liquid surface.  
         [0040]    This method of assembly allows the pool skimming apparatus to be constructed as a series of panels which are easily built and interchangeable with panels of similar size and configuration. This method of manufacture reduces the number of unique parts required to configure a skimmer and thus reduces the cost of manufacture, i.e. tooling, inventory, complexity, etc From this example it can be seen that the design of the pool skimmer apparatus lends itself to numerous ways to reduce part count by judicious engineering.  
         [0041]    Referring to FIG. 2, pool skimmer  20  installed for use in a swimming pool  210  by positioning skimmer  20  adjacent to the edge  210  and supporting skimmer  20  by support means  111  consisting any convenient means on the edge  210 , preferably simple weight lying next to the pool. Skimmer  20  extends towards the interior  206  of the pool  205  and away from edge  210  so that skimmer  20  is partially immersed longitudinally with the water level generally bisecting inlet  115 . The orientation of skimmer  20  is such that the generally circular pool current generated by the force of water emitted from pump nozzle  200  flows into inlet portion  115  along with any debris  220  which may be floating on the pool&#39;s surface. The most obvious orientation is for a clockwise current in the Northern hemisphere, although skimmer  20  may be oriented for either counter-clockwise or clockwise currents.  
         [0042]    For commercial applications, the orientation of the skimmer is essentially the same as that of domestic operations. Note also that the collection area of the device may be optionally located at the proximal end if desired. In operation, as seen in FIG. 3, it has been observed that debris collects in collection area  240  and is not returned to the swimming pool  205 , regardless of how full collection area  240  becomes. While the mechanics of this phenomenon are not well understood, it is believed that they act as follows. As the pool current carrying floating debris  220  flows towards inlet portion  115 , the netting at location  227  resists the current sufficiently to create a differential in force of current measured at inlet area  235  and collection area  240 . This differential in current force causes a secondary current which flows around leading point  226  of the frame, through the collection side  225 , and into collection area  240 . Some flow of water continues through the netting at location  227 , and joining the secondary current, continues through collection area  240  into receiving area  250 . The netting at point  228  prevents debris from exiting the collection area  240  and provides sufficient resistance to divert the current back into its original course This differential in current force, thus created, causes a swirling effect to be observed. Some debris which escapes collection area  240  enters receiving area  250 , where the force of the current flowing through inlet  115  causes debris  220  to collect against netting  229 . As debris collects at netting  229 , it begins to impede the force of the current flowing through netting  229 . This causes a lessening of the current force, thereby allowing debris to float free against said current and towards inlet portion  115 . However, this release of debris from the netting  229  reduces the impediment to current flow. Debris floating free from netting  229  is forced by the current flowing through inlet area  235  back through collection side  225  into collection area  240  before it can escape inlet area  235  back into the swimming pool. Eventually, the different forces acting upon the debris reach an equilibrium and the circular secondary current is observed.  
         [0043]    Commercial applications utilizing this process are complicated by differing liquid viscosities, current forces, and temperature, all of which affect the choice of netting and frame material. However, it is believed that the process of debris collection functions as described above.  
         [0044]    While only a preferred embodiment has been illustrated and described, obvious modifications may be made within the scope of this invention and the following claims without substantially changing its functions. Accordingly, the scope of the invention should be determined not by the embodiments illustrated but by the appended claims and their legal equivalents.