Patent Publication Number: US-2004042855-A1

Title: Coupling structure for a leaching chamber

Description:
TECHNICAL FIELD  
       [0001] The present invention relates to leaching chambers.  
       BACKGROUND  
       [0002] A leach field is used to disperse a fluid into the ground. The fluid is typically effluent from a septic tank. The leach field includes a series of leaching chambers, coupled in series and buried in the ground. A pipe conveys the effluent from the septic tank to the leach field, where the effluent spreads through the series of chambers that are oftentimes coupled end to end. Each chamber has perforated side walls and an open bottom through which the effluent escapes to be absorbed into the surrounding soil.  
       [0003] Each chamber must support the weight of the soil above it, along with anything resting on the soil, such as a vehicle. Therefore, the chamber walls are typically corrugated to increase weight bearing strength. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0004]FIG. 1 is an exploded perspective view of a first leaching chamber according to the present invention;  
     [0005]FIG. 2 is a perspective view of a portion of the first leaching chamber and of a second such leaching chamber;  
     [0006] FIGS.  3 - 5  are sectional views of the leaching chambers of FIG. 2, shown sectioned along line  3 - 3  of FIG. 2 and in different orientations relative to each other, with the orientations corresponding to successive steps in a process of coupling the chambers together;  
     [0007]FIG. 6 is a sectional view of the leaching chambers, shown sectioned along line  3 - 3  of FIG. 2 and coupled together; and  
     [0008]FIG. 7 is a view similar to FIG. 6, with the leaching chambers shown sectioned along line  7 - 7  of FIG. 2.  
    
    
     SUMMARY  
     [0009] An embodiment of the invention is a leaching chamber. The leaching chamber is configured to be coupled in series to another such leaching chamber located forward of the chamber and to yet another such leaching chamber located rearward of the leaching chamber. The leaching chamber comprises a conduit defining a cavity. The conduit includes a front section having an overlying wall and a rear section having an underlying wall. The overlying wall is configured to overlie the underlying wall of the forward chamber when the chambers are coupled together. The underlying wall is configured to underlie an overlying wall of the rearward chamber when said chambers are coupled together. A projection extends from the front section of the conduit. A pocket is located at the rear section of the conduit. The projection is configured to be received by the pocket of the front chamber, and the pocket is configured to receive the projection of the rear chamber. A notched structure defines a notch that is spaced from the front edge of the front section. The notched structure is configured to capture in the notch the underlying wall of the forward chamber when the chambers are coupled together.  
     [0010] Preferably, the pocket is configured to enable the projection of the forward chamber to pivot relative to the pocket when the projection is received by the pocket, so as to enable the forward chamber to pivot into and out of a coupled position. The notched structure is configured to enable the notch to swing into a position in which the notch captures the underlying wall of the forward chamber. The leaching chamber further comprises a hole in the overlying wall and a post extending radially outward from the underlying wall. The hole is configured to receive the post of the forward chamber when the chambers are coupled together. Correspondingly, the post is configured to be received by the hole of the rearward chamber when the chambers are coupled together.  
     [0011] Another embodiment comprises first and second chambers. The chambers include coupling structures that prevent the uncoupling of the chambers through translational movement of the chambers. Instead, the coupling structures enable the uncoupling to be achieved through a pivoting motion of the first chamber relative to the second chamber.  
     DESCRIPTION  
     [0012] The apparatus  6  shown in FIG. 1 has parts which, as described below, are examples of the elements recited in the claims.  
     [0013] The apparatus  6  comprises a first leaching chamber  10 . The chamber  10  is used to disperse a fluid, such as effluent from a septic tank, into the ground. In its installed position, the chamber  10  is coupled in series with other such leaching chambers to form a leach field that is buried in the ground. The chambers may be positioned both end-to-end and side-to-side. An end  12  of the chamber  10  is capped with an end cap  16 , which has an opening to receive the end of a pipe  18 . The pipe  18  conveys the effluent from the septic tank to the leach field, where the effluent spreads through the series of chambers. The first chamber  10  comprises a first conduit  20  with an open bottom  22  and openings  24  through which the effluent escapes to be absorbed into the surrounding soil.  
     [0014] The first conduit  20  is an arched wall extending about a central axis  30  to define an axially extending cavity  36 . The conduit  20  is corrugated in that it comprises an axially extending alternating series of perforated crowns  44  and valleys  46 . The crowns  44  and valleys  46  are arched and separated from each other by radially-extending walls  47 . The valleys  46  are reinforced with axially-extending and radially-extending external ribs  48 . Correspondingly, the crowns  44  are reinforced with axially-extending and radially-extending internal ribs  49  (FIG. 3).  
     [0015] As shown in FIG. 2 the frontmost crown  50  includes a front section  52 . The front section  52  includes a front edge  54  defined by a bead  56 . The front section  52  also includes an overlying wall  60  extending rearward from the front edge  54 . The overlying wall  60  is arched, with an open bottom end  62  (FIG. 1) and an opposite top side  64  having a central peak  66 .  
     [0016] Two holes  70  in the overlying wall  60  are located symmetrically about the central peak  66  at the top side  64  of the overlying wall  60 . A projection  80 , in this example a tongue, extends forward from and coplanar with the front section  52  at the central peak  66 .  
     [0017] Two notched structures  90  extend radially inward from the front section  52 , symmetrically spaced about the central peak  66 . The notched structures are formed from axially-extending reinforcement ribs  92  that reinforce the overlying wall  60 , and are extensions of ribs that reinforce the crowns  44 . The notched structures  90 , which include the bottom surface  94  of the overlying wall  60 , define notches  96  that are spaced axially rearward from the front edge  54 . In molding the chamber  10 , formation of the notches  96  may be facilitated by incorporating holes in the front section  52  above the notches  90  to make room for a core.  
     [0018] A portion of a second leaching chamber  110  is also shown in FIG. 2. The second chamber  110  is like the first leaching chamber  10 . Consequently, each feature described with reference to the second chamber  110  is also included on the first chamber  10 . A portion like the portion of the second leaching chamber shown in FIG. 2 is positioned at the opposite end, the end not show of the first leaching chamber. Thus, each leaching chamber includes both a front section  150  and a rear section  152 , as discussed in greater detail below.  
     [0019] The second chamber  110  includes a second conduit  120  extending about a central axis  130 . Like the first conduit  20 , the second conduit  120  is corrugated, with crowns  144  and valleys  146  separated by radially-extending walls  148 .  
     [0020] The rearmost crown  150  of the second chamber  110  includes a rear section  152  with a rear edge  154 . The rear section  152  includes an underlying wall  160  extending forward from the rear edge  154 . The underlying wall  160  is configured to underlie the overlying wall  60  of the first chamber  10  when the chambers  10  and  110  are coupled together. Like the overlying wall  60 , the underlying wall  160  is arched, with a top side  164  having a central peak  166 . The underlying wall  160  is separated from the remainder of the rear section  152  by a rearward-facing shoulder  168 . The radially-extending height H1 of the shoulder  168  equals the wall thickness T of the overlying wall  60  of the first chamber  10 .  
     [0021] Two posts  170  extend outwardly from the underlying wall  160  and are located symmetrically about the central peak  166  at the top side  164  of the overlying wall  160 . The posts  170  are configured to be received by the holes  70  of the first chamber  10  when the chambers  10  and  110  are coupled together.  
     [0022] A pocket  180  is located at the rear section  152 . The pocket  180  is configured to receive the projection  80  of the first leaching chamber  10  when the leaching chambers  10  and  110  are coupled together. The outside opening  182  of the pocket  180  is defined in the shoulder  168 . The pocket  180  is raised slightly above the shoulder  168  on the crown  144 . In addition, the pocket  180  has an open bottom, which is useful in joining the first chamber  10  to the second chamber  110 , as discussed below.  
     [0023] The first step in coupling the chambers  10  and  110  together is illustrated in FIG. 3. The second chamber  110  lies horizontally on the ground. The first chamber  10  is oriented such that the projection  80  is near and directed obliquely toward the pocket opening  182 . Next, as shown by an arrow  184 , the projection  80  is translationally moved toward and into the pocket  180 . This continues until the front edge  54  abuts the shoulder  168 , as shown in FIG. 4. The point of abutment on the shoulder  168  serves as a pivot point  186  in the following step.  
     [0024] As indicated by arrow  190  in FIG. 5, the first chamber  10  is pivoted downward about the pivot point  186 . Concurrently, the following things happen. The projection  80  pivots upward about the pivot point  186 , as indicated by an arrow  192 . The holes  70  move downward and receive the posts  170 . Also, the notched structure  90  swings into a capturing position in which the underlying wall  160  is captured in the notch  96 . As the notched structure  90  swings downward, the rear edge  154  of the underlying wall  160  rubs against and bends the front edge  194  of the notched structure  90  until the notched structure  90  snaps into the capturing position. In a preferred embodiment, edge  194  has a resiliency to allow it to substantially maintain its original shape after the underlying wall  160  is captured in notch  96 .  
     [0025]FIG. 6 shows the chambers  10  and  110  in a coupled position. In this position, translational movement (i.e., motion without rotation, for example purely axial or purely radial motion) of front section  52  the first chamber  10  relative to the rear section  152  of the second chamber  110  is limited, as follows. The posts  170  are captured in the holes  70 . This limits axial movement of the front section  52  away from the rear section  152 . Also, the underlying wall  160  is captured in the notch  96 . This limits radially-inward and radially-outward translational movement of the underlying wall  160  relative to the overlying wall  60 . Radially-outward movement of the underlying wall  160  is also limited by abutment of the projection  80  against the top wall  196  of the pocket  180 . Different modes of movement are also limited or deterred in other ways as evident to those of skill in the art. In each description above of limiting translational movement, the extent of movement that can occur is a function of the clearance, if any, between abutting structures and the flexibility of those structures.  
     [0026] Consequently, the posts  170  captured in the holes  70 , the projection  80  captured in the pocket  180 , and the underlying wall  160  captured in the notched structure  90  all deter uncoupling of the front and rear sections  52  and  152  through translational movement. However, these structures enable pivotal movement of the front and rear sections  52  and  152 . For example, although the pocket  180  has the upper wall  196  that limits radially outward movement of the projection  80 , the pocket  180  lacks a lower wall or other structure that would prevent downward pivoting of the projection  80  within the pocket  180 .  
     [0027] In fact, the posts  170  and holes  70  in combination with the projection  80  and pocket  180  not only enable, but require the coupling and uncoupling to be achieved through a pivoting motion of the first chamber  10  relative to the second chamber  110  because the projection  80  is spaced forward the posts  170 . At the beginning of the coupling process, depicted in FIG. 3, the projection  80  is directed downwardly into the pocket opening  182  while the overlying wall  60  remains sufficiently tilted upwardly and raised to clear the post  170 . The inward movement ends when the front edge  54  abuts the shoulder  168 . At that point, the hole  70  slips over the post  170  to allow the overlying section  60  to pivot downwardly. Similarly, in the uncoupling process, with the axially-extending projection  80  vertically captured in the opening  182 , the first chamber  10  is pivoted upwardly to raise the overlying wall  60  sufficiently to clear the post  170 .  
     [0028] As shown in FIG. 6, the height H2 of the notch  96  is greater than the thickness T of the underlying wall  160  captured by the notch  96 . Furthermore, the notch  96  is axially spaced from the front edge  54 . These factors enable the notch structure  90  to swing into the capturing position without being blocked by the underlying wall  160 . The swinging movement is hindered, but not prevented, by the rear edge  154  of the underlying wall  152  rubbing against the front edge  194  of the notched structure  90 , because the notched structure  90  bends to accommodate the swinging movement.  
     [0029] As mentioned above, the height H1 (FIG. 2) of the shoulder  168  equals the wall thickness T of the overlying wall  60 . Consequently, as illustrated in FIG. 7, when the chambers  10  and  110  are coupled together, the top surfaces  200  and  202  of the front and rear sections  52  and  152  follow a single smooth curve interrupted only by the bead  56 , projections  170 , and pocket  180 .  
     [0030] In the above described embodiment, as shown in FIG. 2, each of the overlying and underlying walls  60  and  160  has a hole and a projection, to respectively mate with a corresponding projection and hole of the other wall. Specifically, the overlying wall  60  has the hole  70  and the axially-extending projection  80 . The underlying wall  160  also has a hole, referred to the pocket opening  182 , and a radially-extending projection, referred to as the post  170 .  
     [0031] However, in an alternative embodiment, both the axially-extending and radially-extending projections  80  and  170  can extend from the overlying wall  60 , and both holes  70  and  182  can be in or adjacent the underlying wall  160 . In such an embodiment, the radially-extending post  170  extends downward from the overlying wall  60 , instead of upward from the underlying wall  160  as shown in FIG. 2. Other positions may also be utilized for the posts  170  and holes  70 .  
     [0032] As shown in FIG. 1, the first chamber  10  has two lower holes  210  and two corresponding lower posts  220 , that are similar to the upper holes  70  and upper posts  170  described above. In the process of coupling the chambers  10  and  110  together, as the first conduit  20  is pivoted downward, its side walls are bent slightly to enable the lower holes  210  of the first chamber  10  to receive the lower posts  220  of the second chamber  110 . These holes  210  and posts  220  can be positioned on either end of the chamber in a number of different positions.  
     [0033] Referring to FIG. 1, the end cap  16  has, at its front side  230 , upper and lower holes  232  and  234  configured to receive the upper and lower posts  170  and  220  when the end cap  16  is coupled to the rear section  152  of the chamber  10 . The end cap  16  also has, at its rear side  240 , upper and lower posts  242  and  244  configured to be received by the upper and lower holes  70  and  210  when the end cap  16  is coupled to the front section  52  of another chamber  10 .  
     [0034] Although the chambers  10  and  110  in this example are made of polyethylene, the invention applies to any suitable material. Similarly, the invention applies to a chamber of any suitable shape and size. Also, although one projection  80 , two posts  170  and two notched structures  90  are shown in the example, different numbers of each structure and different suitable locations for each structure are possible.  
     [0035] While various features of the claimed invention are presented above, it should be understood that the features may be used singly or in any combination thereof. Therefore, the claimed invention is not to be limited to only the specific embodiments depicted herein.  
     [0036] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.