Abstract:
An apparatus and method are disclosed for the installation of a drain field using a bin that receives an aggregate fill material and has an outlet for releasing the fill material into a trench to create a layer of the aggregate. A guide within the bin receives a corrugated drain field pipe and positions the pipe into the center of the fill material. The apparatus is propelled forward on a pair of gauge wheels using a backhoe or motorized means and causes the fill material to be released and the pipe laid therein. A roller on the rear of the bin places a layer of water absorbent geotextile material atop the aggregate as the apparatus moves forward.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to the creation of conventional sewage disposal systems and, in particular to an apparatus and method for laying drain field pipe, aggregate, and geotextile fabric into a drain field trench.  
           [0002]    Conventional sewage disposal systems are created in conjunction with residential and commercial buildings for the disposal of human waste. These sewage disposal systems are built in rural areas where municipal sewage utilities are not available. A typical installation of said sewage system consists of a concrete septic tank that is set a determined depth into the ground. An outlet of the septic tank is generally a few inches from the top of the tank. The level of the outlet determines the level of a drain pipe exiting from the septic tank into the drain field. The drain pipe is corrugated to leech waste passing through the pipe, and the corrugated drain pipe is laid on a level plane in a trench that is dug to comprise the drain field. The drain field trench may be about three feet wide and two to three feet in depth. The drain pipe rests in the trench on a bed of aggregate fill material, such as gravel. The gravel surrounds the drain pipe holding the pipe level and centered within the bed of gravel. Once the drain field material and drain pipe is laid, a special geotextile fabric paper is layered on top of the drain field and is covered by backfilling of soil and landscaping.  
           [0003]    The process described for creating a convention sewage disposal system by placing the pipe, fill material, and paper into a trench is quite labor intensive. Typically, the process is undertaken using shovels and rakes to fill the trench uniformly and level the fill material for placing the drain pipe requires the labor of more than one person. Furthermore, leveling the drain field material by eye is difficult and requires even more workman time. Thus, the cost of manual labor contributes significantly to the cost of installing a sewage disposal system and a need exists to decrease the labor required. Wasted material while installing a sewage system is yet another concern that is fostered by the use of manual labor that causes waste of gravel during transfer by shoveling and the scattering of gravel on the ground where it may be a future nuisance. Therefore, a further need exists to decrease the amount of wasted fill material and cleanup during installation of a sewage system.  
         SUMMARY OF THE INVENTION  
         [0004]    A method and apparatus are disclosed in the present invention for installing a drain field in a sewage disposal system. A drain field trench is dug on 45 degree angles and a drain pipe is laid in the trench. An apparatus of the present invention having a bin full of aggregate fill material such as gravel is set into the trench at a point of beginning. The pipe laid downstream from the apparatus is fed through a guide cylinder of the apparatus. The apparatus includes an outlet for the fill material, and entrance of the pipe into the guide cylinder is at about the center of the outlet. The apparatus moves downstream in the trench with the pipe feeding through the guide cylinder. As the apparatus moves, fill material exits the outlet by force of gravity. The fill material is supplied beneath the pipe such that the pipe rests on a uniformly deep bed of material. Further, fill material exits the outlet above the pipe such that a uniformly deep bed of material covers the drain pipe. A paper roller is attached to the apparatus above the outlet, and geotextile fabric paper is installed on the roller. The loose end of the paper is attached to the drain pipe such that as the apparatus is propelled downstream in the trench the paper will be applied to the top of the fill material. The dimensions of the outlet and the apparatus are in accordance with the required width and depth of the drain field to be installed and may vary according to specifications for sewage disposal systems. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    [0005]FIG. 1 is a perspective view of the apparatus of the present invention showing the bin and outlet features of the invention as well as the roller and guide.  
         [0006]    [0006]FIG. 2 is a top plan view of the same apparatus.  
         [0007]    [0007]FIG. 3 is a side view of the apparatus of the present invention showing the installation of drain field gravel, drain pipe, and paper into a trench.  
         [0008]    [0008]FIG. 4 is a front view of the same apparatus installing a drain field and being propelled forward by towing the apparatus by chain.  
         [0009]    [0009]FIG. 5 is a rear view of the same apparatus installing a drain field. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0010]    Referring to the drawings, the drain field apparatus of the present invention is exemplified by the embodiment shown in FIG. 1. The main body of the apparatus comprises a bin  2  having an intermediate pass through section  4 , and an outlet  6  for distributing an aggregate fill material  8  into a trench  10 . The bin  2 , also referred to as a hopper or gravel bin, receives the fill material  8  for drain field installation. Any fill material  8  having desirable properties for sewage disposal drain fields could be used with the present apparatus. Common fill materials  8  include gravel and rubber. The apparatus described herein is especially efficient when used with gravel like fill material  8  because the gravel flows well and evenly from the apparatus during distribution in a drain field trench  10 . The fill material  8  will be referred to as gravel material  8  herein without intending to limit the fill materials  8  that are included within the scope of the invention.  
         [0011]    As shown in the figures, the bin  2  includes four downwardly sloping wall panels  12 ,  14 ,  16 ,  18  consisting of a pair of side panels  12 ,  14 , a front panel  16 , and a rear panel  18 . A vertically oriented rim  20  extends from the top of the wall panels to form the top opening of the bin  2  where fill material  8  is added to the bin  2 . The intermediate pass through section  4  or pass through box  4  includes vertically oriented rear  22  and side walls  24 ,  26  and a front wall  28  having a portion  30  thereof that slopes downwardly toward the rear  32  of the apparatus. The front wall  28  of the pass through box  4  directs the gravel  8  into the outlet  6  such that the pass through box  4  functions as a means for feeding gravel  8  to the outlet  6  for effective distribution into the trench  10 .  
         [0012]    As the gravel  8  is fed by force of gravity into the outlet  6  at the bottom  34  of the apparatus, it passes through an opening that forms the outlet  6  at the rear  32  of the apparatus. The size of the opening for the outlet  6  is determined by the depth and width of the gravel bed  36  to be applied in the drain field  38 . For instance, in the case of a drain field  38  having a depth of one foot and a width of three feet, the outlet  6  opening will measure about 15 inches tall and about 34 inches wide. Further, as illustrated in the drawings, the outlet  6  opens to the floor  40  of the trench  10  to further promote the release of gravel material  8  into the trench  10 .  
         [0013]    A guide  42  is attached within the pass through box  4  of the apparatus for receiving a corrugated drain field pipe  44 . The guide  42  may consist of a guide tube  42  of tubular steel as shown, but is not limited thereto. The guide  42  provides a means for positioning the drain pipe  44  as needed for installation of a drain field. In the illustrations, the guide tube  42  runs from the front  46  of the apparatus to the rear  32  of the apparatus such that the inserted drain pipe  44  passes through the apparatus. The drain pipe  44  is first set out downstream of a point of beginning for the apparatus. The guide tube  42  receives the drain pipe  44  at a first end  48  at the front  46  of the apparatus, and the drain pipe  44  exits the guide tube  42  at a second end  50  of the guide tube  42  at the rear  32  of the apparatus and connects to a septic tank outlet. The guide tube  42  is oriented within the pass through box  4  such that the exiting drain pipe  44  that is fed through the guide tube  42  is positioned in the center of the gravel bed  36  laid by the apparatus. Thus, the second end  50  of the guide tube  42  terminates at about the center of the gravel outlet&#39;s  6  vertical opening.  
         [0014]    A roller  52  is attached to the rear  32  of the apparatus on the bin  2  or on the pass through box  4 . As shown in FIG. 1, the roller  52  is attached to the bin  2  and includes a bracket  54  and roll bar  56  that hold a roll of paper or fabric  58 . A special water absorbent paper or geotextile fabric material  58  is used in sewage drain fields atop the gravel bed  36 . The roller  52  allows the paper  58  to be attached to the drain pipe  44  and installed at the same time as the distribution of gravel material  8  and centering of the drain pipe  44 .  
         [0015]    A support bar  60  as shown in FIG. 2 may be attached at the top of the bin  2  for reinforcement and a lift tab  62  may be attached to each side  12 ,  14  of the bin  2  for lifting the apparatus and removing the apparatus from a trench  10 .  
         [0016]    Movement of the apparatus in the trench  10  is facilitated by a pair of wheels  64  that are mounted on an axle  66  or spindles at the front  46  of the apparatus. The wheels  64  may consist of standard automobile tires  68  and rims  70 . Further, the axle  66  or spindles may be vertically adjustable to permit adjustment of the level of the front  46  of the apparatus in the trench  10  and allow the wheels  64  to gauge the trim of the apparatus in the trench  10 . The bottom edges  72  of the pass through box  4  flare slightly downward toward the rear  32  of the apparatus. The downward flare of the edges  72  promotes movement of the apparatus in the trench  10  by allowing some space between the floor surface  40  of the trench  10  and the bottom edges  72  of the pass through box  4  except at the very rear edge  74  of the apparatus.  
         [0017]    When installing a drain field  38  for a sewage disposal system using the described apparatus, a drain field trench  10  of about ten to twelve feet in length is dug with a backhoe. In the present invention, the trench  10  is preferably dug on 45 degree angles such that the apparatus in FIG. 1 does not have to navigate comers in which the apparatus must be turned more than 45 degrees. The apparatus of FIG. 1 is able to negotiate 45 degree turns successfully.  
         [0018]    To begin using the apparatus, it is set in the trench  10  beginning near a septic tank previously placed in the ground. Corrugated drain pipe  44  is rolled out downstream from the septic tank. One end of the drain pipe  44  is installed through the guide tube  42  such that the drain pipe  44  enters the front  46  of the apparatus and exits the rear  32  of the apparatus. A paper roll  58  is installed on the roller  52  of the apparatus and attached to the drain pipe  44  exiting the rear  32  of the apparatus. The bin  2  is filled with gravel  8  that is gravity fed through the bin  2  and exits through the outlet  6 . The apparatus is propelled forward in the trench  10  about eight feet with a backhoe. The apparatus may be self-propelled or may be pulled through the trench  10  as illustrated by the chain  76  attached to the apparatus in FIGS.  2 - 4 . The movement of the drain pipe  44  through the guide tube  42  stimulates the uniform and efficient application of gravel material  8  from the outlet  6  into the trench  10 .  
         [0019]    The apparatus moves downstream in the trench  10  with the pipe  44  feeding through the guide  42 . As the apparatus moves, the fill material  8  or gravel exits the outlet  6  by force of gravity. The fill material  8  is supplied beneath the pipe  44  such that the pipe  44  rests on a uniformly deep bed  36  of material  8 . Further, fill material  8  exits the outlet  6  above the pipe  44  such that a uniformly deep bed  36  of material  8  covers the drain pipe  44 . The paper  58  attached above the outlet  6  is applied to cover the fill material  8  as the apparatus is propelled downstream in the trench  10 .  
         [0020]    Once the trench  10  is filled with drain field material  8 , then the process is repeated as needed. An additional trench  10  is dug using the backhoe on an angle of 45 degrees or more. The drain pipe  44  is laid downstream. The bin  2  is refilled with gravel  8 . The apparatus is propelled forward in the trench  10 , and the drain field  38  of gravel material  8 , drain pipe  44 , and drain field paper  58  is laid. Once completed, the apparatus is removed from the trench  10 , and the backhoe is used to backfill with soil before landscaping.  
         [0021]    From the foregoing description of the illustrative embodiments of the invention, it will be apparent that many modifications may be made. The embodiments described exemplify the invention, and the invention is not limited thereto. Therefore, it is intended that the claims are to cover all such modifications that fall within the true spirit and scope of the invention.