Abstract:
A method and apparatus provide for the killing of insects by trapping the larvae, which either prevents development into adults or traps the adults developed from the larvae to prevent further reproduction and harm. In one preferred embodiment, the apparatus includes a container with an inverted cone or other protrusion and a second non-horizontal surface, such as a funnel, positioned above the inverted cone. The funnel defines an opening above the inverted cone. A barrier may also be included that abuts the underside of the funnel. A liquid such as water is placed in the container at a level at least above the opening such that eggs laid in the water become larvae that swim downward and are directed through the opening by the funnel and are directed away from the opening by the inverted cone. The larvae either drown, if the water level is above the barrier, or else become trapped adult mosquitoes that cannot escape from the container. It is noted that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to ascertain quickly the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Description:
RELATED APPLICATIONS  
       [0001]    This application claims priority to U.S. Provisional Application No. 60/413,963 filed on Sep. 26, 2002 and entitled MOSQUITO LARVA TRAP, which is incorporated herein in its entirety. 
     
    
     
       TECHNICAL FIELD  
         [0002]    This invention relates in general to insect control, and in particular to the capture and killing of insects such as mosquito larvae before they become adult biting mosquitoes.  
         BACKGROUND  
         [0003]    Mosquitoes are more than just an annoying problem. From the 1800s when British Army Doctor Donald Ross proved malaria was transmitted by mosquitoes, to the present United States outbreak of the mosquito borne West Nile virus, mosquitoes have proven to be a serious problem for both man and animals. Some other diseases transmitted by mosquitoes are dengue, yellow fever, and encephalitis varieties such as Eastern Equine encephalitis, Western Equine encephalitis, La Crosse encephalitis, St. Louis encephalitis, and Japanese encephalitis.  
           [0004]    The quest to prevent mosquito transmitted diseases and the general annoyance of being bitten while engaged in outdoor activities has been long and generally unsuccessful. Primary methods of control have been directed at large scale sprayings of indiscriminate poisonous chemicals, attractant traps directed at killing adult mosquitoes, draining of breeding areas such as wetlands, or the application of larvicide chemicals in bodies of water.  
           [0005]    Many poisonous chemicals not only kill mosquitoes, but also destroy beneficial insects as well as having detrimental effects on other wildlife such as birds. DDT is still a cause of ecological damage after over thirty years of non-use in the United States. Draining of wetlands has been recognized as destructive to the overall health of our environment and the use of larvicide chemicals in these areas is expensive, requires repeated applications during the breeding season, and could have long term side effects as yet undetermined. Various types of traps have been introduced that attract adult mosquitoes by the use of light, emissions of chemical attractants, carbon dioxide releases, and even vibrating membranes that mimic animal skin. The killing mechanisms used by these traps tend to be electrocuting devices, vacuuming insects into holding bags, introducing the insects to poisonous chemicals, or providing a sticky surface on which the insects become trapped. Many of these traps are expensive to produce and require extensive maintenance for their operation.  
           [0006]    All of the above trapping methods result in the unintended destruction of beneficial insects. Current studies indicate existing commercially available traps such as the light attractant and carbon dioxide emitting varieties tend to attract disproportionately greater numbers of mosquitoes to an area than they actually kill. This action creates a negative impact on the intended result of mosquito elimination from a particular location. It has also been shown that the ratio of beneficial insects killed versus mosquitoes by many of these devices is sufficiently high that quite a few of these traps are actually regressive to the environment.  
           [0007]    Mosquito populations grow exponentially with one adult female laying from a few to over one hundred eggs every third day of her breeding life. Obviously, the attracting and killing of individual mosquitoes using existing art is, at best, a check-stop measure as the existing art fails to kill mosquitoes in large numbers and break the cycle that allows the exponential growth of the population.  
         SUMMARY  
         [0008]    Embodiments of the present invention address these issues and others by providing a method and apparatus that captures mosquito larvae to prevent them from developing into adult mosquitoes that are otherwise free to continue to reproduce and cause harm. Embodiments provide an attractive location for mosquitoes and other harmful insects to lay eggs while trapping and killing the larvae developing from these eggs and/or trapping and killing adult mosquitoes that have developed from the trapped larvae.  
           [0009]    One embodiment is an apparatus for killing insects. One preferred design of the apparatus includes a container and a protrusion within the container, in which at least a portion of the protrusion is preferably sloped relative to horizontal. The apparatus also includes a directing member within the container that is positioned above the protrusion and having at least a portion that is non-horizontal. The directing member defines an opening that is located above the protrusion. The protrusion, directing member, and container define a chamber that for containing insect larvae and prevent those larvae from maturing into insects or, if they mature, from exiting the container.  
           [0010]    Another embodiment is a method of killing insects with a container, such as the one described above. The method involves placing liquid in the container so that the liquid level is above the opening of the directing member and partially fills the chamber. The container is positioned such that insect eggs are laid on the liquid surface and the insect eggs hatch into larvae. The method further involves directing or guiding the larvae to drop from the liquid surface along the directing member and out of its opening. After the larvae pass through the opening, the method preferably further involves directing the larvae to further drop or otherwise move into the chamber. When the larvae reach this location, they have little chance of surviving and exiting the chamber alive.  
           [0011]    Another preferred embodiment of the present invention includes a container and an inverted cone member within the container. A funnel-shaped member is located within the container above the inverted cone and defines an opening above the inverted cone. The embodiment further includes a barrier that has a first edge that abuts the underside of the funnel-shaped member and has a second edge that abuts the container. At least the barrier, the funnel-shaped member, and the container define a chamber.  
           [0012]    Additional embodiments of the present invention include a container and a floor within the container, and the floor may include at least a portion that is sloped relative to the horizontal. A directing member is positioned above the floor and has at least a portion that is non-horizontal. The directing member defines an opening above the floor. The floor, directing member, and container define a chamber that traps the insect larvae. The container may be translucent while the directing member may be opaque such that the larvae are drawn away from the opening and further into the chamber toward the sidewall regardless of whether the bottom is sloped or flat.  
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a front view of an illustrative container of one embodiment showing a concave bottom and a protrusion centered on the container bottom.  
         [0014]    [0014]FIG. 1. 1  is a top plan or birds-eye view of the container of FIG. 1 showing center alignment of the protrusion.  
         [0015]    [0015]FIG. 2 is a front view of an illustrative funneling device of one embodiment that fits into the container of FIG. 1.  
         [0016]    [0016]FIG. 2. 1  is a top plan view of the funneling device of FIG. 2 showing center alignment of its lower opening.  
         [0017]    [0017]FIG. 3 is a top plan view of an illustrative ascension barrier of one embodiment.  
         [0018]    [0018]FIG. 3. 1  is a front view of the ascension barrier of FIG. 3.  
         [0019]    [0019]FIG. 4 is an exploded front view of one embodiment of the present invention showing the assembly process.  
         [0020]    [0020]FIG. 5 is a front cross-sectional view of the assembled embodiment shown in FIG. 4.  
         [0021]    [0021]FIG. 5. 1  is a cut away cross-sectional view of an illustrative snap-on lid portion of the funnel of FIG. 2 connected to the container of FIG. 1.  
         [0022]    [0022]FIG. 6 is an isometric cross-sectional view of FIG. 5.  
         [0023]    [0023]FIG. 7 is an alternative cross-sectional view of FIG. 5 after water has been placed into the container to a level adequate to drown the larvae.  
         [0024]    [0024]FIG. 8 is an alternative cross-sectional view of FIG. 7 after water has been placed into the container to a level adequate to trap adult mosquitoes that have developed from the trapped larvae.  
         [0025]    [0025]FIG. 9 is a front cross-sectional view of one assembled alternative embodiment that has a sloped bottom within the container.  
         [0026]    [0026]FIG. 10 is a front cross-sectional view of one assembled alternative embodiment that has a flat bottom within the container.  
     
    
     DETAILED DESCRIPTION  
       [0027]    The present invention is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. As used in the specification and in the claims, “a,” “an,” or “the” can mean one or more, depending upon the context in which it is used. The preferred embodiment is now described with reference to the figures, in which like numbers indicate like parts throughout the figures.  
         [0028]    The present invention provides a trap for insect larvae, in particular mosquito larvae, and a method of using such a trap. The larvae are contained so that they either drown or develop into adult mosquitoes that are unable to exit and eventually starve, depending upon the particular embodiment of the present invention and the corresponding level of liquid being used. The present invention, accordingly, assists in breaking the cycle of the exponential increase in mosquito populations.  
         [0029]    One preferred embodiment of the present invention comprises a container, a protrusion or inverted cone member, a directing member or funnel, and, optionally, a barrier. FIG. 1 is a front view of an exemplary container  50  according to one embodiment, in which a vertical axis V bisects the center of the container  50  and is used for reference throughout the drawings. In this embodiment, the container  50  is shown as being round in shape, but other shapes including polygons of various numbers of sides are also applicable. The container  50  may be made from various materials such as plastic or metal. However, translucent plastic allows the inside of the container  50  to be viewed by an observer to verify the functioning of the apparatus and also allows light to enter the container to further draw the larvae toward the light, as discussed below.  
         [0030]    The container  50  includes various attributes. A sidewall  62  of the container  50  may optionally include a ledge  18  for an optional ascension barrier, discussed below, to rest on with the ledge  18  so as to separate an upper sidewall region  16  from the remainder of the sidewall  62 . In this embodiment, a bottom surface  20  of the container  50  is concave to have a slight inward taper or slope forming a raised base.  
         [0031]    Still referring to FIG. 1, a modified conical structure  22 , which is an inverted cone, is positioned on the apex of the bottom  20 . The conical structure  22  of this embodiment has a first sloped region  52  and second sloped region  54 , with the top sloped region  52  having less slope. The taper of the bottom surface  20  of the container  50  has an even lesser slope extending between the conical structure  22  and the sidewall  62 . As one skilled in the art will appreciate, if an object falls or drifts into the center of the container bottom  20 , the conical structure  22  and concave design of the bottom direct that object toward the sidewall  62  of the container  20 . Other manners of obtaining this same effect with the bottom  20  is to have a parabolic cross-section between the sidewall  62  and center or to have a consistent slope extending from the apex to the sidewall  62 . As discussed below in relation to FIG. 9, other formations for the bottom of the container are applicable as well, such as having a substantially planar bottom of the container that is either flat or sloped relative to the horizontal and spans the diameter of the round bottom of the container  50 .  
         [0032]    [0032]FIG. 1. 1  is a top plan view of the container  50  depicting a ‘y’ axis Y and the perpendicular ‘x’ axis X in center alignment along with the top rim  14 , which is also shown in FIG. 1. The optional ledge  18  is also shown, on which the optional ascension barrier may rest. The modified conical structure  22  of this particular embodiment is also shown. Optional holes  42  allow a simple bent wire handle (not shown) to be connected to the container  50  to facilitate carrying it.  
         [0033]    The present invention also preferably comprises a non-horizontal top surface to assist in directing or guiding larvae downwardly, and FIG. 2 shows a funnel  60  that is one exemplary embodiment. The funnel mounts within the container  50  and has a funnel sidewall  26 , funnel top opening rim  24 , funnel bottom opening rim  30 , and optional funnel vent holes  28 , which allow air trapped during the filling process to escape when the apparatus is filled with liquid after being assembled. Such vent holes  28  are not necessary when ventilation is not required, such as when the container  50  is filled with liquid prior to the additional components such as funnel  60  being inserted into the interior of the container  50 . The top opening rim  24  preferably attaches onto the top rim  14  of the container  50  by interlocking together, which is shown in FIG. 5. 1 .  
         [0034]    As discussed in more detail below, the sloped sidewall  26  of the funnel  60  directs larvae to the bottom rim, which defines an opening  30  therethrough. In use, the sinking or downwardly moving larvae pass through the opening to the bottom surface  20 , where they are directed toward the sidewall  62  of the container  50  and away from the opening  30 . Thus, the slope of the sidewall  26  of the funnel  60  directs the larvae to its opening, and then once through, the slope of the bottom surface directs the larvae away from the opening to decrease the likelihood of reentry into the interior of the funnel  60 . As discussed above, the conical structure  22  further assists in directing the larvae to the sidewall of the container and impedes the larvae from reentering into the interior of the funnel  60 .  
         [0035]    The sidewall  26  of the funnel  60  may be constructed of various materials such as plastic or metal. However, a dark, visible light-absorbing coloring provides the most attractive location for eggs to be laid by the harmful insects, such as biting mosquitoes. A black non-horizontal top surface is especially attractive to mosquitoes. Having an opaque funnel also prevents light from entering the container near the opening  30  such that larvae are not attracted back toward the opening after the larvae have already passed through it.  
         [0036]    One skilled in the art will appreciate that the slope of the sidewall  26  of the funnel  60  can vary. One consideration is that the opening  30  is sufficiently small so that the larvae cannot easily reenter the interior of the funnel after exiting it. The slope is also a function of the dimensions of the container, i.e., a shorter container with a wide top opening will use a different slope that a taller container with a narrow top opening. One contemplated embodiment of the funnel  60  has a top opening rim  24  having a diameter of 7.25 inches inside the rim and 8 inches outside of the rim; a bottom opening  30  with a diameter of one inch, a vertical height between the top and bottom openings of 4 inches, and an included angle of 77 degrees relative to horizontal to define the slope. It should be noted that these dimensions are provided only for purposes of illustration of one embodiment and that various other dimensions are also applicable. Accordingly, these dimensions are not intended to limit the scope or meaning of the claims.  
         [0037]    While the funnel  60  provides a suitable non-horizontal top surface for the illustrated embodiment, various other non-horizontal top surfaces may also be used. For example, an inverted cone could be utilized in which the inverted cone provides a slope leading to one or more openings along the outer rim rather than providing an opening in the center, such that the larvae are directed downward and toward the outer portion of the cone and through openings at the outer portion. However, where such an inverted cone is utilized to provide a top slope, the bottom surface of the container is provided a reversed slope, which leads from the sidewall  62  downward to a center location to direct the larvae to the center of the bottom surface, which is away from the openings of the top surface. Other examples of a non-horizontal top surface include having a consistent slope leading across the diameter of the container  50  with an opening defined by the surface in proximity to the sidewall  62  or having a vertical surface extending downward but terminating above the sloped bottom surface to define an opening.  
         [0038]    [0038]FIG. 2. 1  shows the funnel bottom opening rim  30 , optional funnel vent holes  28 , and the optional alignment holes  42  for handle insertion.  
         [0039]    Referring now to FIG. 3, the optional ascension barrier  80  is shown having optional vent holes  32 , an outer rim  34 , and an ascension barrier-locking ring  36 . The barrier  80  rests on the ledge  18  of the container  50  and the barrier-locking ring  36  defines a hole in the center into which the funnel  60  is received such that the opening  30  of the funnel  60  is located below the ledge  18  and ascension barrier  80 . The barrier-locking ring  36  complementarily receives and contacts the underside of the funnel  60  to create a barrier between the funnel  60  and sidewall  62  of the container  50 . The ascension barrier  80  may be constructed of various materials such as plastic or metal. As noted above for the funnel  60 , the vent holes  32  of the ascension barrier are optional and are not necessary when the apparatus is assembled after the liquid has already been poured into the container  50 . The vent holes  32  are preferably of a dimension such that the larvae cannot easily pass through them, if at all.  
         [0040]    [0040]FIG. 3. 1  is a front view of the ascension barrier  80  showing the outer rim of ascension barrier  34  and funnel-locking ring  36 . From this view, it can be appreciated that once installed, the outer rim  34  contacts the ledge  18  of the container while the funnel-locking ring  36  contacts the funnel  60  such that a barrier is created. This barrier  80  may be included in the apparatus where the liquid is filled above the barrier  80  so that larvae cannot reach the surface of the water due to the barrier and drown. Including the barrier  80  allows this mode of operation to occur without requiring that the liquid be filled all of the way to the top rim  14  of the container. However, other modes of operation will also serve to kill the harmful insects, as discussed below.  
         [0041]    [0041]FIG. 4 provides an exploded view of one illustrative embodiment of the apparatus  10  of the present invention, in which the funnel  60 , the optional ascension barrier  80 , and the container  50  are correctly aligned for assembly. Thus, for this embodiment, the optional barrier  80  is first placed into the container  50  and is seated on the ledge  18 . Then the funnel  60  is placed into the container  50  where it is seated within the locking ring  36  of the barrier  80  and fits onto the top rim  14  of the container  50 .  
         [0042]    [0042]FIG. 5 shows the assembled apparatus  10 . A detailed view of a funnel-locking ring  40 , which is snapped into place over the top rim  14  of the container  50 , is shown in FIG. 5. 1 . As noted above, the funnel sidewall  26 , directs the larvae in a downward direction toward and out of its opening  30 , where they are further directed away from this opening by the conical structure  22  and further encouraged to move away from this area by the concave bottom  20  of the container  50 . At this point, the larvae are in an entrapment chamber  38 , which is defined by the bottom  20  of the container  50 , sidewall  62  of the container  50 , sidewall  26  of the funnel  60 , the conical structure  22 , and the barrier  80  if present.  
         [0043]    Referring now to FIG. 6, the apparatus  10  is shown in cross-section, in which the funnel  60  is connected to the container  50  by the funnel-locking ring  36  at the ledge  18  of the container  50 . The sidewall  26  of the funnel  60 , with optional vent holes  28 , slopes to the bottom rim  30  of the funnel  60  which opens into the entrapment chamber  38  by passing around the conical structure  22 , which is a molded part of the concave bottom  20  of this embodiment but could be a separate component installed within the container  50 . Larvae attempting to get to the surface of the liquid to breathe while in the entrapment chamber  38 , are blocked by the barrier  80 , which is held in place below the surface of the liquid by both the ascension barrier collar  36  and ledge  18 , and the larvae drown.  
         [0044]    In operation the assembled structure  10  is filled to a particular level with liquid. Such liquid may be water from any source, utilizing anything from a stagnant pool to fresh tap water. The water is filled to at least a level above the bottom opening  30  of the funnel  60 . As discussed above, the apparatus  10  may be assembled prior to filling with water. In that case, ventilation holes in the ascension barrier  80 , if the barrier  80  is present, and in the funnel  60 , allow air to escape as the water displaces it. In addition to water, oviposition material  120  as shown in FIGS. 7 and 8 may be placed in the apparatus  10  to advance the stagnation of the water so as to draw mosquitoes more quickly. That is, the oviposition material depletes oxygen from the water, which also accelerates the drowning of the trapped larvae. Examples of such oviposition material include non-animal fat materials such as pot-bellied pig chow, oatmeal, alfalfa, rice hulls, and brewer&#39;s yeast. While oviposition material containing animal fat such as rabbit pellets may be used to further stagnate the water, a layer of grease may form on the water surface thereby lessening the attraction of mosquitoes to use the apparatus  10 .  
         [0045]    The apparatus  10  is placed in a location where it is likely that mosquitoes will be present to lay eggs. For example, the apparatus may be placed in a shaded area preferably in grassy locations or near bushes. As shown in FIGS. 7 and 8, mosquitoes are attracted to the still water  100  (FIG. 7),  100 ′ (FIG. 8) present atop the funnel  60  and lay their eggs  102  within it.  
         [0046]    The eggs  102  float on top of the water  100 ,  100 ′ until they hatch into larvae  104  approximately twenty-four to forty-eight hours later. The larvae  104  breathe at the surface of the water  100 ,  100 ′ instead of ingesting oxygen from the water itself, and drift or swim to the bottom to hide. The funnel sidewall  26  directs the larvae  104  down and toward the center where they emerge from the bottom opening  30  of the funnel  60 , and are directed into the entrapment chamber  38 , and away from the bottom rim  30  of the funnel  60  by the conical structure  22 , and also by the light entering through the container  50 , if translucent. Once within the entrapment chamber  38 , the concave bottom  20  of the container  50  encourages further movement away from the bottom opening  30  of the funnel  60  toward an outer region  106 .  
         [0047]    As shown in FIG. 7, when the need for oxygen causes the larvae  104  to swim toward the surface of the water  100 , they are blocked by the ascension barrier  80 , and drown at a region  108  since the water  100  has been filled to a level above the barrier  80 . In trials, an occasional larva  104  found its way out of the entrapment chamber  38  and back through the bottom rim  30  of the funnel  60 . However, if that occurs, the process starts again by that larva  104  again swimming downwardly back in the entrapment chamber  38 , where it will drown.  
         [0048]    The method of killing the insects as shown in FIG. 7 may also work without the ascension barrier  80  present if the water  100  is filled all the way to the rim  24  of the funnel  60 . Thus, once the larvae  104  enter the entrapment chamber  38  and begin to swim upward toward the surface, the larvae encounter the underside of the funnel  60  and drown.  
         [0049]    [0049]FIG. 8 shows the water level in the apparatus  10  below the ascension barrier  80  but above the bottom rim  30  of the funnel  60 . The apparatus  10  continues to work but uses a different method. In this situation, larva confined to the entrapment chamber  38  can reach the surface of the water  100 ′ to breathe and eventually mature into adult mosquitoes  112 . However, because adult mosquitoes  112  cannot swim underwater, they remain trapped in the entrapment chamber  38  and quickly die of starvation. In this scenario, the ascension barrier  80  continues to be optional because once the adult mosquito  112  develops, the underside of the funnel  60  traps the mosquito  60  if the barrier  80  is not present.  
         [0050]    The converse of this scenario of a low water level is too much rain, which overflows the apparatus  10 . Since the apparatus is designed to work at full water depths as noted above, either with or without the ascension barrier, heavy rains do no harm with the excess simply spilling over the side. Any eggs  102  or larvae  104  that spill over onto the ground with the excess water quickly die of dehydration since they must be in water to survive.  
         [0051]    [0051]FIG. 9 shows one of the various alternatives to the embodiment shown in FIGS.  1 - 8 . The apparatus  90  of FIG. 9 includes a container  50 ′ having a bottom  92  that forms a sloped surface relative to horizontal, as opposed to including a protrusion such as the conical structure  22  of FIGS.  1 - 8 . The sloped surface of the bottom  92  directs the larvae toward the sidewall  62  upon the larvae passing through the opening  30  of the funnel  60 . The larvae are then trapped within the entrapment chamber  38 ′ defined by the bottom  92 , sidewall  62  and funnel  60  where they drown or starve once an adult mosquito. As with the previous embodiment, the ascension barrier  80  may be included to further define the entrapment chamber  38 ′.  
         [0052]    It will be appreciated that the bottom  92  of this embodiment may be substantially planar, parabolic, concave, or of other curvature that slopes away from the opening  30  and into the entrapment chamber  38 ′. Furthermore, it will be appreciated that the bottom  92  may also be augmented at the area below the opening  30  with a protrusion such as a conical structure as described above. Additionally, it will be appreciated that the funnel  60  may be opaque while the container  50  is translucent to further discourage the larvae from swimming toward the opening  30  while encouraging the larvae to swim toward the sidewall  62  and further into the entrapment chamber  38 ′.  
         [0053]    [0053]FIG. 10 shows another of the various alternatives to the embodiments shown in FIGS.  1 - 9 . The apparatus  150  of FIG. 10 includes a container  50 ″ having a bottom  92 ′ that is flat relative to the horizontal, as opposed to forming a sloped surface relative to horizontal and as opposed to including a protrusion such as the conical structure  22  of FIGS.  1 - 8 . The flat surface of the bottom  92 ′ may not direct the larvae toward the sidewall  62  upon the larvae passing through the opening  30  of the funnel  60 , but some larvae will swim toward the sidewall  62  without the direction from the bottom  92 ′. The larvae are then trapped within the entrapment chamber  38 ″ defined by the bottom  92 ′, sidewall  62  and funnel  60  where they drown or starve once an adult mosquito. As with the previous embodiments, the ascension barrier  80  may be included to further define the entrapment chamber  38 ″. The level of the liquid that is used to fill the container is at least above the opening  30  but may either be above or below the ascension barrier  80 .  
         [0054]    It will be appreciated that the that the funnel  60  may be opaque while the container  50  is translucent to further discourage the larvae from swimming toward the opening  30  while encouraging the larvae to swim toward the sidewall  62  and further into the entrapment chamber  38 ″. Thus, while the bottom  92 ′ may not provide direction to the larvae, the light entering through the translucent container  50 ″ will provide the effect of drawing the larvae toward the sidewall  62  and further into the entrapment chamber  38 ″.  
         [0055]    The exemplary apparatus and designs illustrated and discussed above in relation to FIGS.  1 - 10  may include several individual components. These components may be individually formed and assembled to complete the apparatus or one or more of these components may be integral with another. It will be appreciated that whether to have the components separately formed and assembled or as integral components formed together at the time of manufacture is a matter of design choice. Additionally, it should be noted that the non-horizontal directing member above the bottom  92  may be shaped in other ways. For example, the opening  30  may be defined at various locations other than in the center, such as in proximity to the sidewall  62  at a location that is near the upper intersection of the bottom  92  and the sidewall  62 .  
         [0056]    The various embodiments described above are provided by way of illustration only and should not be construed to limit the invention. Those skilled in the art will readily recognize various modifications and changes that may be made to the present invention without following the example embodiments and applications illustrated and described herein, and without departing from the true spirit and scope of the present invention, which is set forth in the following claims.