Abstract:
A flow leveling device for use in a liquid distribution system that can be attached to the end of a conduit The device has an eccentrically placed opening on the face of the device whose vertical position can be varied so as to equalize the flow of liquid dispersed from a central point. The device is secured to the conduit by a double-walled skirt depending from the face of the device. The skirt has a central gap defined by the double walls which securely holds the conduit walls therein.

Description:
FIELD OF THE INVENTION 
     This invention relates to a device for equilibrating the flow of liquid out of a central container where the container may not be leveled and more particularly relates to an adjustable weir for fitting as a cap onto the inlet end of fluid distribution pipes originating in a wastewater junction box. 
     BACKGROUND OF THE INVENTION 
     In the treatment of wastewater and particularly wastewater that has been treated in a septic tank, or the like, the effluent from the septic tank is transferred into a drain field wherein the effluent is absorbed into the soil. In the preparation of these drain fields to it receive wastewater effluent, trenches are generally dug in a preselected arrangement and distribution pipes with drainage openings therein are laid into the trenches and covered with gravel, sand and soil. 
     In the initial treatment of wastewater, the wastewater flows into the septic tank from sewage disposal systems, such as toilets, and the solids settle to the bottom of the tank as the liquids move out through an outlet in the upper portion of the septic tank. The liquid separated from the solids in the septic tank is normally discharged as a partially clarified liquid into subsequent treatment containers including, for example, distribution or junction boxes. This water or liquid is then discharged from the junction boxes to the drain fields by means of distribution pipes exiting the junction boxes. 
     Sometimes when the junction boxes are installed, or after installation due to uneven settling of the soil, the disposition of the different entry ends of the distribution lines is not along the same vertical planes. The result is that during times of low fluid flow, the wastewater drains first out the distribution lines with entry ends positioned along the lowest vertical plane. This causes more wastewater to enter areas of the drain field served by the lower placed distribution lines and an unequal absorption and dissemination of the wastewater. 
     Besides unleveled distribution boxes, similar situations arise resulting in uneven distribution of fluids where even distribution or control over distribution is desired. For example, it is also desirable to regulate the flow of liquid through recirculation lines in media based treatment systems. 
     One solution to this type of problem is to provide flow-equalizing weirs that can be individually adjusted to vary the flow of liquid through each exit location. In septic systems with distribution lines, this can be accomplished through the use of end caps secured over the open ends of the distribution pipes within the junction box. The end caps have a variety of means of varying the height of an opening through the end cover. This permits leveling of all the openings in the distribution pipes within the junction box. 
     However, these devices often have multiple parts and use a complicated system of manipulating the height of the opening. Multiple parts require more expensive and difficult manufacturing techniques as well as being more difficult for the user to maneuver. Also, the means of securing the device to the distribution pipe has proven to be unsatisfactory. Typically, a single-walled skirt either wraps around or inserts into the distribution pipe. This does not usually provide a very secure fit, especially if there are slight variations in pipe diameter or pipe wall thickness. Also, this means of securing the device to the pipe requires different sized devices for every size pipe and even pipes of the same size with varying wall thickness must each use different devices. 
     SUMMARY OF THE INVENTION 
     It is accordingly a primary object of the present invention to provide an effective means for equalizing fluid flow out of unleveled containers. 
     More particularly, it is an object of the present invention to provide a height adjustable weir for liquid distribution systems. 
     Further, it is an object of the present invention to provide an end cover for the inlet end of fluid distribution pipes originating in a wastewater junction box and wherein the cover has an eccentrically placed opening which can be rotated to change the vertical level of the opening. The opening acts as a weir to promote the even distribution of wastewater out of the distribution box. 
     Even further, it is an object of the present invention to provide an end cover with an eccentrically placed opening for the inlet end of fluid distribution pipes that attaches to the distribution pipe end with a double-walled skirt attached to and extending outward from the end cover. The double-walled skirt allows for a more secure and watertight fit of the end cover to the pipe and flexibility as to the variance in pipe wall thickness accommodated by the skirt than does a single-walled skirt. 
     Another object of the present invention is to provide a junction box having at least one outlet wherein the outlet has a flow leveling device attached thereto. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A better understanding of the invention will be had upon reference to the following description in conjunction with the accompanying drawings in which like numerals refer to like parts throughout the several views and wherein: 
     FIG. 1 is a perspective view of a junction box of the present invention; 
     FIG. 2 is a perspective view from the outside of a preferred flow leveling device of the present invention; 
     FIG. 3 is a perspective view of FIG. 2 from the inside of the flow leveling device of the present invention; 
     FIG. 4 is a bottom view of FIG. 2; 
     FIG. 5 is a top view of a second embodiment of a flow leveling device of the present invention; 
     FIG. 6 is a bottom view of FIG. 5; 
     FIG. 7 a  is a cross-sectional view of an embodiment of a flow leveling device of the present invention showing the inner and outer walls in detail; 
     FIG. 7 b  is a cross-sectional view of another embodiment of a flow leveling device of the present invention showing the inner and outer walls in detail; and 
     FIGS. 8 a, b, c , and  d  are end elevation views of a flow leveling device of the present invention secured to a pipe end and showing different radial positions of the opening along different vertical planes. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In FIG. 1 is shown an example of a junction box  50  and attached fluid distribution pipes  52  for a wastewater treatment system. Wastewater flows from a septic tank through an effluent line  60  and empties into the junction box  50 . The junction box  50  is of usual construction as is generally known in the art. It may include a removable top lid (shown removed) that permits access to the interior space of the junction box  50  and the flow leveling devices  10  attached to the entry ends  53  of the fluid distribution pipes  52 . The junction box  50  has a plurality of openings  55  for attachment of fluid distribution pipes  52 . Preferably, there is at least one opening  55  and attached fluid distribution pipe  52  for each side wall  51  of the junction box  50 , exclusive of the side wall  51  having the opening  54  for the effluent line  60 . There may be two or more openings  55  per side wall  51  to allow greater dispersion of the wastewater out of the junction box  50 . 
     In use, the junction box  50  is placed in the soil or on whatever surface it will be supported by and is leveled as accurately as possible. The effluent line  60  as well as the various distribution pipes are inserted through the effluent line openings  54  and fluid distribution pipe openings  55 , respectively, with the entry end of the fluid distribution pipe  52  extending a short distance into the junction box  50 . Wastewater that enters the junction box  50  through the effluent line  60  will flow out from the junction box  50  through the plurality of distribution pipes  52  and empty into the drainfield. Sometimes, due to either inaccuracies in the initial leveling, or due to settling of the supporting surface over time, the junction box  50  will not be level. This results in water draining unevenly out of the junction box  50 . In order to alleviate this problem, flow leveling devices  10  of the present invention are affixed to the entry ends  53  of the fluid distribution pipes.  52 . The flow leveling device  10  is then rotated so that the eccentrically placed opening  30  on each device aligns along the same vertical plane, thus assuring even flow of the wastewater out of the junction box  50 . The position of the eccentrically placed opening  30  may be adjusted as needed over time to return the flow pattern to the desired state. 
     As shown in FIGS. 2 and 3, an embodiment of the present invention comprises a flow leveling device  10  having an end closure  20 . The end closure  20  is provided with a hole or opening  30  through which liquid flows. The hole  30  is placed offset, or eccentrically, from the center of the end closure  20 . Depending from the end closure  20  is a double-walled skirt  40  that finctions to secure the flow leveling device  10  to the fluid distribution pipe  52 . The fluid distribution pipe  52  slides into the interwall gap  44  formed between the double walls of the skirt  40  and is gripped and secured on the pipe&#39;s  52  interior and exterior wall surfaces thus holding the flow leveling device  10  securely to the fluid distribution pipe entry end  53 . 
     The flow leveling device may be constructed as a unitary piece from rigid but pliable materials. The flow leveling device  10  may be constructed from plastics such as polypropylene or polyethylene having the required physical characteristics. Utilizing a unitary construction design permits ease of manufacture. For example, if an injection molding process is used to construct the flow leveling device  10 , a single mold can be constructed and used to produce the entire device in one step. This greatly reduces cost over a device requiring two or more molds and an additional assembly step. 
     As shown in FIGS. 2,  3  and  4 , the end closure  20  is comprised of an outer face  21  and an inner face  22 . The outer face  21  faces into the junction box  50  and has direct and initial contact with the wastewater in the junction box  50 . The inner face  22  is directed toward the interior of the fluid distribution pipe  52 . Depending from the outer periphery of the inner face  22  is the double-walled skirt  40 , which secures the entry end of the fluid distribution pipe  52  to the end closure  20 . The eccentrically placed opening  30  is placed near the periphery of the end closure and the flow leveling device  10  can be rotated so as to level the flow of waste water between all the fluid distribution pipes  52  exiting the junction box  50 . 
     The eccentrically placed opening  30  is positioned on the end closure  20  offset from the center and near the periphery so as to form a weir that restricts the flow of wastewater into the fluid distribution pipe  52  and out of the junction box  50 . As demonstrated in FIGS. 8 a, b, c , and  d , the wastewater level  32  must rise to the level of the lowermost edge  31  of the opening  30  before it can enter into a particular distribution pipe  52  to which the flow leveling device  10  is attached. By rotating the flow leveling device  10 , the vertical plane on which the lowermost edge  31  resides is altered relative to the level of the: wastewater either permitting or inhibiting the free flow of liquid into the distribution pipe  52 . If a particular junction box  50  is not level, the flow of wastewater out of the junction box  50  and into the distribution pipes  52  attached to the different side walls  51  will be unequal, resulting in one or more drain fields receiving more or less fluid than the rest. Utilizing flow leveling devices  10  secured to each of the entry ends  53  of all the fluid distribution pipes  52  exiting from the junction box  50 , the lowermost edge  31  of each opening  30  can be adjusted so that each lies in the same vertical plane. This will create equal distribution of wastewater into each of the fluid distribution pipes  52 , resulting in an equal volume of fluid entering each point of the drain field or fields. It may also be desirable to have an unequal flow of fluid into one or more fluid distribution pipes  52 . If such is the case, one or more flow leveling devices  10  may be rotated so that the lowermost edge  31 l of the opening  30  rests on a different vertical plane than another flow leveling device  10 . This will cause fluid to first enter the distribution pipe  52  with a flow leveling device having a lowermost edge  31  along the lowest vertical plane. Wastewater will not enter other fluid distribution pipes  52  until the overall fluid level within the junction box  50  rises to the lowermost edge  31  of each opening  30 . The overall result is an unequal distribution of wastewater volume through the fluid distribution pipes  52 . Thus, rotating flow leveling device  10  in order to change the vertical level of the eccentrically placed opening  30  allows the user to accurately control the flow of fluid out of the junction box  50  and into the fluid distribution pipe  52 . 
     FIGS. 3 and 4 best illustrate the double-walled skirt  40  depending from the periphery of the inner face  22  of the end closure  20 . The inner wall  41  and outer wall  42  of the skirt  40  both depend and extend outward from the inner face of the end closure  22  for a distance necessary to securely support and hold the flow leveling device  10  to the end of a fluid distribution pipe  52 . As shown in FIGS. 3,  4  and  7   a , the inner wall  41  and outer wall  42  can depend parallel relative to each other from the inner face  22  and perpendicular to the inner face  22  of the end closure  20 . In an alternative embodiment, as shown in FIG. 7 b , the inner wall  41  and outer wall  42  may depend at an inward angle relative to each other from the inner face of the end closure  22 . In another embodiment, not illustrated in the figures, only one of the walls  41  and  42  may be biased toward the other. The extent of the angle may vary up to an angle resulting in the upper ends  43  touching or nearly touching, as illustrated in FIG. 7 b . Regardless of the angle of the inner wall  41  and outer wall  42  relative to each other, a space between the walls, or interwall gap  44  is created. The interwall gap  44  accommodates the entry end  53  of the fluid distribution pipe  52 . The inner wall  41  and outer wall  42  snugly grasp the entry end  52  of the fluid distribution pipe  52  and hold the flow leveling device securely to the distribution pipe  52 . The distance between the walls  41  and  42  creating the interwall gap  44  is selected so as to snugly accommodate the thickness of the distribution pipe  52 . Double walls possess an advantage over single walls fitting either around or inside a pipe in that with double walls the pipe is held more securely. An outer wall is in direct contact with the exterior surface of a pipe while an interior wall directly contacts an interior wall. The extra contact results in twice as much frictional contact with the surfaces of a pipe, resulting in a “vice-like” securing of the flow leveling device  10  to the distribution pipe  52 . 
     Utilizing angled walls  41  and  42  as shown in FIG. 7 b  allows for a greater variation in accommodated pipe wall diameters. The angled walls  41  and  42  can be semi-rigid yet flexible enough to permit a pipe  52  of varying diameter to be pushed between the slight gap of the walls  41  and  42 , biasing the walls  41  and  42  apart just enough to permit passage of the entry end  53  of the pipe  52  and further down until stopping at the inner face  22  of the end closure  20 . The tension created by biasing the walls  41  and  42  apart results in a greater pressure holding the pipe end  53  in the interwall gap  44  than would exist without the biasing. The distance between the walls  41  and  42  is greater toward the wall end depending from the inner face  22  of end closure  20  and as such, a pipe end  52  having a greater wall thickness will still fit within the interwall gap  44  that also accommodates a smaller wall thickness pipe. For example, in one embodiment of the device of the present invention, the flow leveling device  10  can be secured to both thin-walled SDR  35  piping having a minimum wall thickness of 0.12 inches +/−10% as well as Schedule  40  piping having a wall thickness of 0.296 inches. 
     Again referring to FIGS. 7 a  and  7   b , in another embodiment of the present invention, the top edges  43  of the inner wall  41  and outer wall  42  can have beveling  44 . The beveling  44  provides a larger area of insertion for the entry end  53  of the fluid distribution pipe  52  and makes it easier to insert and guide the entry end  53  into the interwall gap  44 . The angle of the beveling may vary as necessary to accommodate different needs of the user. 
     FIGS. 5 and 6 demonstrate a further embodiment of the device of the present invention. Either the outer periphery of the outer face  21  of the end closure  20  or the entire outside surface of the outer wall  42  can have gripping ridges  45  that assist the user in applying a rotational force to the flow leveling device  10 . The user may need to apply this force when initially securing the flow leveling device  10  to the fluid distribution pipe  52 , or at a later time when necessary to adjust the position of the opening  30 . The gripping ridges  45  may have a scalloped appearance, or other such design as is necessary to facilitate a better grasp by the user on the flow leveling device  10 . 
     The device may be used in any system where control over the flow of fluids is desirable. For example, the device may be used in recirculation lines from media based treatment systems. In a recirculation device for wastewater treatment systems, filtered effluent is shunted in two different directions. A fraction of the effluent is sent to the drainfield and percolated into the ground while a second fraction is directed back to the beginning of the system for further filtering. The recirculation device has a return line from a media based treatment location. The return line has a multiplicity of recirculation valves that work to divide the wastewater and distribute it in different directions. The device of the present invention may be fitted onto these valves. By adjusting the device, more or less of the wastewater may be directed in one or another direction. 
     The foregoing detailed description is given primarily for clearness of understanding. No unnecessary limitations are to be understood therefrom for modifications will become obvious to those skilled in the art upon reading this disclosure and may be made without departing from the spirit of the invention and scope of the appended claims.