U.S. patent application number 11/462671 was filed with the patent office on 2007-04-12 for flexible arch-shaped corrugated structure.
This patent application is currently assigned to ADVANCED DRAINAGE SYSTEMS, INC.. Invention is credited to Terry M. Birchler, James B. Goddard, Stephen R. Helmrich.
Application Number | 20070081860 11/462671 |
Document ID | / |
Family ID | 37594927 |
Filed Date | 2007-04-12 |
United States Patent
Application |
20070081860 |
Kind Code |
A1 |
Goddard; James B. ; et
al. |
April 12, 2007 |
FLEXIBLE ARCH-SHAPED CORRUGATED STRUCTURE
Abstract
A flexible arch-shaped corrugated structure includes a plastic
structure that can be light weight and easy to handle, while at the
same time having suitable strength for carrying loads. By suitably
engineering the corrugations, the need for structural ribs can be
eliminated and thinner sidewalls can be used. The structure can
include a series of vertically-oriented arched corrugations having
surfaces that convexly arch or curve upwardly as well as laterally.
Having both upward and lateral arched or curved features on the
corrugations can provide increased strength to the corrugations and
the structure. In a particular embodiment, the plastic structure is
a leaching chamber. The structure can include access or inspection
port structures disposed at the ends of the structure. The ports
are dimensioned to mate with the opposing port of a like structure.
In particular, the mated structures can articulate or rotate about
the mated ports.
Inventors: |
Goddard; James B.; (Powell,
OH) ; Helmrich; Stephen R.; (Powell, OH) ;
Birchler; Terry M.; (New Albany, OH) |
Correspondence
Address: |
R.D. JOHNSON & ASSOCIATES, P.C.
70 WALNUT STREET
WELLESLEY HILLS
MA
02481
US
|
Assignee: |
ADVANCED DRAINAGE SYSTEMS,
INC.
4640 Trueman Blvd.
Hilliard
OH
|
Family ID: |
37594927 |
Appl. No.: |
11/462671 |
Filed: |
August 4, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60707490 |
Aug 10, 2005 |
|
|
|
Current U.S.
Class: |
405/49 ;
138/121 |
Current CPC
Class: |
E03F 1/003 20130101 |
Class at
Publication: |
405/049 ;
138/121 |
International
Class: |
E02B 11/00 20060101
E02B011/00 |
Claims
1. A structure having a base with an open bottom, comprising: a
plurality of alternating corrugations, each corrugation being arch
shaped about a center longitudinal axis with the bottom of the arch
being at the base and the crest of the arch being perpendicular to
the base; and the corrugations including a peak corrugation having
a radius when sectioned through the center longitudinal axis, the
radius varying along the arch from the base to the crest of the
arch.
2. The structure of claim 1 wherein the radius is continuously
variable along the arch from the base to the peak.
3. The structure of claim 1 wherein the radius is larger at the
base than at the peak of the arch.
4. The structure of claim 1 wherein the peak corrugation includes
an opening to facilitate the flow of a flowable medium between the
inside of the structure and the outside of the structure.
5. The structure of claim 4 wherein the peak corrugation further
includes louvers to define the openings and to inhibit the
intrusion of external material into the structure.
6. The structure of claim 1 wherein the corrugations are
plastic.
7. The structure of claim 1 wherein the corrugations are not
connected with structural ribs.
8. The structure of claim 1 wherein the corrugations have a wall
thickness of about 0.1 inches.
9. A corrugated plastic chamber having a base with an open bottom,
comprising: an arch-shaped plastic body having a length and
opposing ends; a plurality of alternating corrugations running
along the length of the body, each corrugation being arch shaped
about a center longitudinal axis with the bottom of the arch being
at the base and the crest of the arch being perpendicular to the
base; and the corrugations including a plurality of peak
corrugations, each having a radius when sectioned through the
center longitudinal axis, the radius varying along the arch from
the base to the crest of the arch.
10. The chamber of claim 9 wherein the radius is continuously
variable along the arch from the base to the peak.
11. The chamber of claim 9 wherein the radius is larger at the base
than at the peak of the arch.
12. The chamber of claim 9 wherein each of the peak corrugations
includes an opening to facilitate the flow of a flowable medium
between the inside of the chamber and the outside of the
chamber.
13. The chamber of claim 12 wherein each of the peak corrugations
further includes louvers to define the openings and to inhibit the
intrusion of external material into the chamber.
14. The chamber of claim 9 wherein the corrugations are not
connected with structural ribs.
15. The chamber of claim 9 wherein the corrugations have a wall
thickness of about 0.1 inches.
16. The chamber of claim 9 wherein the corrugations have a wall
thickness that does not vary by more than 10%.
17. A leaching chamber for burial in the ground, comprising: an
arch-shaped plastic body having a length and opposing ends; a
plurality of alternating corrugations running along the length of
the body, each corrugation being arch shaped about a center
longitudinal axis with the bottom of the arch being at the base and
the crest of the arch being perpendicular to the base; the
corrugations including a plurality of peak corrugations, each peak
corrugation having: a radius when sectioned through the center
longitudinal axis, the radius varying along the arch from the base
to the crest of the arch; and a plurality of openings along a
portion of the peak corrugation.
18. The leaching chamber of claim 17 wherein the radius is
continuously variable along the arch from the base to the peak.
19. The leaching chamber of claim 17 wherein the radius is larger
at the base than at the peak of the arch.
20. The leaching chamber of claim 17 wherein the peak corrugation
openings facilitate the flow of an effluent from the inside of the
leaching chamber to the outside of the leaching chamber.
21. The leaching chamber of claim 20 wherein the peak corrugation
further includes louvers to define the openings and to inhibit the
intrusion of soil into the structure.
22. The leaching chamber of claim 21 wherein the louvers formed on
the peak corrugations.
23. The leaching chamber of claim 22 further comprising a frame
structure formed on peak corrugations, the louvers being within the
frame structure.
24. The leaching chamber of claim 17 wherein the corrugations are
not connected with structural ribs.
25. The leaching chamber of claim 17 wherein the corrugations have
a wall thickness of about 0.1 inches.
26. The leaching chamber of claim 17 wherein the corrugations have
a wall thickness that does not vary by more than 10%.
27. A leaching chamber for burial in the ground, comprising: an
arch-shaped plastic body having a length and opposing ends; a
plurality of alternating corrugations running along the length of
the body, each corrugation being arch shaped about a center
longitudinal axis with the bottom of the arch being at the base and
the crest of the arch being perpendicular to the base, the
corrugations including; a plurality of peak corrugations, each peak
corrugation having: a radius when sectioned through the center
longitudinal axis, the radius continually varying along the arch
from the base to the crest of the arch, wherein the radius is
larger at the base than at the crest; a plurality of formed louvers
defining openings along a portion of the peak corrugation; a
plurality of valley corrugations between adjacent peak
corrugations, each valley corrugation having a plurality of formed
louvers defining openings along a portion of the valley
corrugations.
28. The leaching chamber of claim 27 wherein the corrugations are
not connected with structural ribs.
29. The leaching chamber of claim 27 wherein the corrugations have
a wall thickness of about 0.1 inches.
30. The leaching chamber of claim 27 wherein the corrugations have
a wall thickness that does not vary by more than 10%.
31. The leaching chamber of claim 27 wherein a plurality of the
valley corrugations includes a pair of stacking features.
32. The leaching chamber of claim 31 wherein each stacking feature
includes: a stacking column extending vertically downward from the
valley corrugation; and a stacking pocket above the valley
corrugation and vertically aligned with the stacking column.
33. The leaching chamber of claim 32 wherein the stacking feature
further includes a rail transitioning the stacking pocket to the
top of the valley corrugation.
34. The leaching chamber of claim 27 further comprising at least
one access port formed in the body.
35. The leaching chamber of claim 34 wherein the access port is
disposed at the crest of a valley corrugation.
36. The leaching chamber of claim 34 wherein there are a pair of
access ports, one access port at each end of the body.
37. A method of manufacturing a structure having a base with an
open bottom, comprising: forming a plurality of alternating
corrugations, each corrugation being arch shaped about a center
longitudinal axis with the bottom of the arch being at the base and
the crest of the arch being perpendicular to the base; and forming
the corrugations to include a peak corrugation having a radius when
sectioned through the center longitudinal axis, the radius varying
along the arch from the base to the crest of the arch.
38. A method of manufacturing a corrugated plastic chamber having a
base with an open bottom, comprising: forming an arch-shaped
plastic body having a length and opposing ends; forming a plurality
of alternating corrugations running along the length of the body,
each corrugation being arch shaped about a center longitudinal axis
with the bottom of the arch being at the base and the crest of the
arch being perpendicular to the base; and forming the corrugations
to include a plurality of peak corrugations, each having a radius
when sectioned through the center longitudinal axis, the radius
varying along the arch from the base to the crest of the arch.
39. A method of manufacturing a leaching chamber for burial in the
ground, comprising: forming an arch-shaped plastic body having a
length and opposing ends; forming a plurality of alternating
corrugations running along the length of the body, each corrugation
being arch shaped about a center longitudinal axis with the bottom
of the arch being at the base and the crest of the arch being
perpendicular to the base; forming the corrugations to include a
plurality of peak corrugations, each peak corrugation having: a
radius when sectioned through the center longitudinal axis, the
radius varying along the arch from the base to the crest of the
arch; and a plurality of openings along a portion of the peak
corrugation.
40. A method of manufacturing a leaching chamber for burial in the
ground, comprising: forming an arch-shaped plastic body having a
length and opposing ends; forming a plurality of alternating
corrugations running along the length of the body, each corrugation
being arch shaped about a center longitudinal axis with the bottom
of the arch being at the base and the crest of the arch being
perpendicular to the base, the forming of the corrugations
including; forming a plurality of peak corrugations, each peak
corrugation having: a radius when sectioned through the center
longitudinal axis, the radius continually varying along the arch
from the base to the crest of the arch, wherein the radius is
larger at the base than at the crest; a plurality of formed louvers
defining openings along a portion of the peak corrugation; forming
a plurality of valley corrugations between adjacent peak
corrugations, each valley corrugation having a plurality of formed
louvers defining openings along a portion of the valley
corrugations.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/707,490, filed on Aug. 10, 2005 (Attorney Docket
No. 1652.2004-000), the teachings of which are incorporated herein
by reference in its entirety.
BACKGROUND
[0002] Arch-shaped corrugated structures are useful for various
applications, particularly where the structure is exposed to load
forces. A typical application is a leaching chamber that can
fabricated from a thermoplastic, such as high density polyethylene
(HDPE). The leaching chamber is typically injection molded into its
shape.
[0003] Plastic leaching chambers are typically connected together
in a series or an array and buried in a leaching field for
dispersing waste water, sewage effluent, or storm water into the
ground. The buried leaching chamber must resist loads from the
overhead soil and possibly vehicular traffic.
[0004] Prior art leaching chambers are typically rigid structures.
Thick sidewalls, plastic structural ribs, and other features, are
generally used to increase the strength of the leaching chambers.
That rigidity can cause the leaching chambers to fail prematurely.
Indeed, many prior art chambers break during shipment or transport
to the installation site, and during installation itself.
[0005] Leaching chambers are generally installed in accordance with
state and local laws and regulations, as well as local customs. In
particular, those laws, regulations, and customs dictate the width
of the leaching field trench, and thus limit the width of the
leaching chamber, generally to either 36 inches, 24 inches, or 18
inches. Most leaching chambers are between about five to six feet
in length to be dimensioned and light enough for an individual
worker to handle.
SUMMARY
[0006] Particular embodiments of a flexible arch-shaped corrugated
structure include a plastic structure that can be light weight and
easy to handle, while at the same time having suitable strength for
carrying loads. In a particular embodiment, the plastic structure
is a leaching chamber.
[0007] Prior art plastic leaching chambers have relied on thick
sidewalls and structural ribs to strength the structure. The ribs,
however, can place portions of the structure under tension when
loaded and have been found to introduce failure points into the
structure. Failures at those points tend to crack and propagate
through the structure's wall to tear the structure. Based on the
locations of prior art ribbing, those failures tend to occur at the
sidewalls.
[0008] Weight reductions can be realized by reducing the amount of
structural ribs and decreasing the wall thickness. However, those
weight-saving measures can decrease the strength of the leaching
chamber.
[0009] By suitably engineering the corrugations, the need for
structural ribs can be eliminated and thinner sidewalls can be
used. Once installed, the flexible structure is strong but light.
The resulting structure will flex before failing. When loaded, the
structure is under compression. When failure does occur, the
structure will fail at the crest of the corrugations by buckling,
not at the sidewalls. In addition to flexing before failing, a
flexible structure is better able to cover uneven ground.
[0010] Aspects of the invention include a structure having a base
with an open bottom. The structure can be a chamber, and more
particularly an arch-shaped leaching chamber. Also included are
methods of fabricating the structure, such as by injection
molding.
[0011] The structure can include a plurality of alternating
corrugations running along the structure's body, with each
corrugation being arch shaped about a center longitudinal axis with
the bottom of the arch being at the base and the crest of the arch
being perpendicular to the base. Furthermore, the corrugations can
include a peak corrugation having a radius when sectioned through
the center longitudinal axis, with the radius varying along the
arch from the base to the crest of the arch.
[0012] The structure can include a series of vertically-oriented
arched corrugations having surfaces that convexly arch or curve
upwardly as well as laterally. Having both upward and lateral
arched or curved features on the corrugations can provide increased
strength to the corrugations and the leaching chamber.
[0013] In particular embodiments, the radius is larger at the base
than at the peak of the arch. The larger corrugation portion at the
bottom can provide greater strength for resisting backfill. More
particularly, the radius of the sectioned peak corrugation can be
continuously variable along the arch from the base to the peak. The
radius blends into the side walls of the corrugations, which can be
slightly angled for strength purposes.
[0014] The structure's corrugations can be fabricated from plastic.
In particular, the corrugations can have a wall thickness of less
than about 0.1 inches and are not connected with structural ribs.
The wall thickness can further be relatively uniform, with the
variation in thickness being less than 10%.
[0015] The peak corrugations can include openings to facilitate the
flow of a flowable medium, such as air, storm water, or sewage
effluent between the inside of the structure and the outside of the
structure. The peak corrugations can further include louvers to
define the openings and to inhibit the intrusion of external
material, such as soil, into the structure. The louvers can, in
particular, be formed as protrusions on the peak corrugations. The
louvers can include louvers with louver members that laterally
extend across the laterally curving surfaces of the corrugations,
resulting in laterally oriented arched louver members. In
particular, the louvers can be formed to include a frame structure
formed on the peak corrugations, the louvers being within the frame
structure. The lateral arch of the louver members on the laterally
curving surfaces of the corrugations can also have increased
strength for resisting the lateral thrust of backfill and can have
increased leaching surface area, in comparison to louvers that are
merely straight.
[0016] The corrugations can include valley corrugations or troughs
between adjacent peak corrugations. Each valley corrugation can
also have a plurality of formed louvers defining openings along a
portion of the valley corrugations.
[0017] In addition, a plurality of the valley corrugations can
include a pair of stacking features. Each stacking feature can
include a stacking column extending vertically downward from the
valley corrugation and a stacking pocket above the valley
corrugation and vertically aligned with the stacking column. The
stacking feature can further include a rail transitioning the
stacking pocket to the top of the valley corrugation.
[0018] The structure (in particular a leaching chamber) can further
include at least one inspection port formed in the body. In one
embodiment, the inspection port can be disposed at the crest of a
valley corrugation.
[0019] The ends of the structure can include end flanges that can
be overlapped and locked with end flanges on adjacent leaching
chambers. The end flanges can be generally arched shaped in a
vertical orientation. One end flange on a chamber can include an
upwardly extending post, and the opposite end flange can include a
mating downwardly facing socket for providing pivotal engagement
between adjacent leaching chambers. The side walls of the end
flanges can have a curved or tapered contour to allow the end
flanges to slide over each other during lateral pivoting of the
leaching chambers relative to each other. In some embodiments, the
end flanges can have a curved contour forming a dome like
structure, resulting in a post and dome locking feature.
[0020] The mating ends of the chambers can include access or
inspection ports, which can be circular in shape and function as
post and dome structures disposed at the crests of the ends. That
is, mated leaching chambers can articulate or rotatably pivot about
the inspection port structures within a fixed range of angles. By
positioning the inspection ports at the ends of the leaching
chamber, a potential structural weakness at the corrugations can be
removed and disposed at the end joint that can be stiffened through
overlapping.
[0021] A plurality of arch-shaped structures can be joined into a
series or an array of structures. In particular, leaching chambers
can be joined together to form a leaching field.
[0022] A particular leaching field can include a first leaching
chamber and a second leaching chamber, which may be alike. Each
leaching chamber can have like end flanges, the end flanges
including a first end flange having a first inspection port
structure and a second end flange having a second inspection port
structure. The first leaching chamber is mated with the second
leaching chamber such that the first inspection port structure of
the first leaching chamber overlaps the second inspection port
structure of the second leaching chamber. At a particular joint,
the first inspection port structure and the second inspection port
structure are opened to allow access to the interior of the
leaching field.
[0023] In addition, the longitudinal axis of the first chamber can
be at an angle relative to the longitudinal axis of the second
chamber. More specifically, the first and second leaching chambers
can rotational pivot about the mated inspection port
structures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The foregoing and other objects, features, and advantages of
the invention, including various novel details of construction and
construction of parts, will be apparent from the following more
particular drawings and description of embodiments, in which like
reference characters refer to the same parts throughout the
different views. The drawings are not necessarily to scale,
emphasis instead being placed upon illustrating the principles of
the invention. It will be understood that the particular details
embodying the invention are shown by way of illustration only and
not as a limitation of the invention. The principles and features
of this invention may be employed and varied in numerous
embodiments without departing from the scope of the invention.
[0025] FIG. 1 is a perspective view of a particular leaching
chamber.
[0026] FIG. 2 is a top view of the leaching chamber of FIG. 1.
[0027] FIG. 3 is a first end view of the leaching chamber 1 of FIG.
1.
[0028] FIG. 4 is a right side view of the leaching chamber 1 of
FIG. 1.
[0029] FIG. 5 is a second end view of the leaching chamber 1 of
FIG. 1.
[0030] FIGS. 6A-6B illustrate the interconnection of adjacent
leaching chambers of FIG. 1.
[0031] FIG. 7 is a cross-sectional view along line A-A of FIG.
4.
[0032] FIG. 8 is a foreshortened cross-sectional view along line
B-B of FIG. 4.
[0033] FIG. 9A is a load/defection curve for a commercial
embodiment of the leaching chamber of FIGS. 1-8.
[0034] FIG. 9B is a load/defection curve for a competitor's
commercially-available Quick 4 leaching chamber.
[0035] FIG. 10 is a perspective view of a leaching chamber having
inspection port ends.
[0036] FIG. 11 is a side view of the leaching chamber 100 of FIG.
10.
[0037] FIG. 12 is a top view of the leaching chamber 100 of FIG.
10.
[0038] FIGS. 13A-13B illustrate the interconnection of adjacent
leaching chambers of FIG. 10.
[0039] FIG. 14 is a cross-sectional diagram of nested chambers
taken along line C-C in a valley corrugation of FIG. 4.
DETAILED DESCRIPTION
[0040] In a particular embodiment of the invention, the flexible
arch-shaped corrugated structure is a plastic leaching chamber,
which has an open bottom and louvered opening side walls for
dispersing effluent from inside the structure to the ground.
Leaching chambers can also be used to disperse storm water. Similar
structures can be used in other applications as well, including
grain aeration and fish channels. In other application, the side
walls may not have louvered openings, such as in culverts.
[0041] FIG. 1 is a perspective view of a particular leaching
chamber. The leaching chamber 1 has an open bottom and is generally
arch shaped with a center axis 5. The chamber has a total length
TL, a width W, and a height H. The leaching chamber 1 includes a
first end flange 10 at a first end and a second end flange 20 at a
second end. The first and second end flanges 10, 20 are
complementary so that the first end flange 10 of one chamber can
mate with the second end flange 20 of an adjacent chamber to form a
serial chain of chambers for a leaching field as understood by
those of ordinary skill in the art.
[0042] In particular, the ends of the leaching chamber can include
end flanges that can be overlapped and locked with end flanges on
adjacent leaching chambers. The end flanges 10, 20 are generally
arched shaped in a vertical orientation. As shown, the end flanges
10, 20 feature a post and dome interconnect, which is described in
more detail in U.S. Design Pat. No. 403,047, issued on Dec. 22,
1998 to Gray, the teaching of which are incorporated herein by
reference. A post structure 12 is located at the crest of the first
end flange 10 and a dome structure 22 is located at the crest of
the second end flange 20. Thus, the second end flange 20 overlaps
the first end flange 10 of adjacent chambers. The first end flange
10 also includes latching grooves 14 and the second end flange 20
includes a lip structure 24.
[0043] A base flange 30 acts as feet for the leaching chamber 1.
When installed, the base flange is set on the surface of a prepared
trench. An elevated flange 32 is fabricated on the base flange 30
adjacent to the first (overlapped) end flange 10. When two like
chambers are mated, the base flange 30 adjacent to the second
(overlapping) end flange 20 is received in the gap under the
elevated flange 32.
[0044] The leaching chamber 1 also includes a plurality of
alternating peak corrugations 40 and valley corrugations or troughs
50 along its length. The corrugations 40, 50 include respective
sidewalls 45, 55 with opening louver features 140 having a height h
for dispersing effluent or storm water from inside the chamber 1.
The distal louvered corrugations are connected to the respective
end flanges 10, 20 via a first end transition corrugation 15 and a
second end transition corrugation (not shown).
[0045] The louver features 140 are formed onto and follow the
profile of the corrugations 40, 50. In particular the amount of
material absent from the corrugation sidewalls due to the louver
slots is replaced by a structural louver frame. In contrast, prior
art louvers are generally formed by simply perforating the
sidewall, which introduces a structural weakness in the
corrugations.
[0046] Also shown is an inspection port 60 located at the crest of
a valley corrugation. When a leaching field is installed, selected
inspection ports 60 can be cut out for later access. It should be
understood that the number and position of access ports can be a
design choice.
[0047] FIG. 2 is a top view of the leaching chamber 1 of FIG. 1.
The laying length LL of the chamber is defined as the longitudinal
distance between the centers of the post structure 12 and the dome
structure 22. This view better illustrates the first end transition
corrugation 15 and the second end transition corrugation 25. Also
note that the corrugations do not have a fixed contour. Also note
that there is no external ribbing between corrugations, as is
frequently used in prior art leaching chambers. Internal ribbing
between corrugations is also not used.
[0048] This view also illustrates tabs 34 on the second end of the
base flange 30. As will be illustrated below, the structure of the
ends permits interconnected chambers to articulate or swivel a
through a small angle so that a series of interconnected chambers
can follow a non-linear path. Other swivel connectors can also be
used, such as those described in U.S. Pat. No. 6,592,293 to Gray,
U.S. Pat. No. 6,592,293 to Hedstrom et al. and in co-pending U.S.
application Ser. No. 10/619,060 by Hedstrom et al., the teachings
of which are incorporated herein by reference in their entirety. Of
course, non-swivel connecting joints can also be employed.
[0049] The latching grooves 14 on the first end flange 10 and the
lip 24 on the second end flange 20 are used to connect end caps to
terminate a series of chambers.
[0050] FIG. 3 is a first end view of the leaching chamber 1 of FIG.
1. In addition to illustrating the arch shape along the center line
5 and the post connector structure 12, details of the peak
corrugation louvers 140 are shown. Note that the louvers 140
include louver members 142a, 142b, . . . , 142y, 142z. Those louver
members protrude from the corrugation side wall.
[0051] FIG. 4 is a right side view of the leaching chamber 1 of
FIG. 1. This view further illustrates the contours of the
corrugations and details of the ends.
[0052] As shown, the leaching chamber 1 includes a series of
vertically-oriented arched corrugations having surfaces that
convexly arch or curve upwardly as well as laterally. The side
walls of the leaching chamber between the corrugations can include
louvers for allowing the passage of liquids from the leaching
chamber. In addition, the corrugations can also include louvers
with louver members that laterally extend across the laterally
curving surfaces of the corrugations, resulting in laterally
oriented arched louver members.
[0053] Having both upward and lateral arched or curved features on
the corrugations can provide increased strength to the corrugations
and the leaching chamber. The corrugations can have sidewalls
having flat surfaces. The lateral arch of the louver members on the
laterally curving surfaces of the corrugations can also have
increased strength for resisting the lateral thrust of backfill and
can have increased leaching surface area, in comparison to louvers
that are merely straight.
[0054] FIG. 5 is a second end view of the leaching chamber 1 of
FIG. 1. In addition to illustrating the arch shape along the center
line 5 and the dome connector structure 22, details of the peak
corrugation louvers 140 are shown. As shown in FIG. 3, the louvers
140 include louver members 142a, 142b, . . . , 142y, 142z. Again,
those louver members protrude from the corrugation side wall.
[0055] FIGS. 6A-6B illustrate the interconnection of adjacent
leaching chambers of FIG. 1. As shown a first chamber 1A and a
second chamber 1B interconnect by overlapping end flanges. As shown
in FIG. 6A, the first chamber 1A is installed in place with its
first end flanges 10A exposed. The second chamber 1B is installed
by placing its second end flange 20B over the first end flange 10A
of the first chamber 1B, with the dome structure 22B aligned over
the post structure (not shown) of the first chamber 1A. Note that
the second chamber 1B is elevated at a vertical angle. As shown in
FIG. 6B, the interconnection is completed by tilting the second
chamber 1B down so that the second chamber base flange 30B is
received under the elevated flange 32A of the first chamber 1A.
Note that the joint, particularly the gap below the elevated flange
32A, allows for articulated movement of the connected chambers.
Latches or other suitable engageable structures on the ends of the
leaching chambers can be used to help hold the mated chambers
together.
[0056] Although two like leaching chambers 1A, 1B are shown being
mated, other structures can also be mated with a leaching chamber.
For example, one or more angle couplers, similar to those described
in the above-referenced U.S. Pat. No. 6,592,293 to Hedstrom et al.,
can be serially attached to a leaching chamber.
[0057] FIG. 7 is a cross-sectional view along line A-A of FIG. 4.
This illustrates a typical peak corrugation louver structure 140
and valley corrugation louver structure 52 of FIG. 1. Referring to
the peak corrugation louver structure 140, a base louver 142a
transitions into the base flange 30 and a top louver 142z extends
from the main corrugation sidewall. Between the base louver 142a
and the top louver 142z are a plurality of interior louvers, of
which the two adjacent to the base louver 142a and the top louver
142z are shown. The louvers 140 are designed to allow flow of
effluent or storm water from within the chamber and to inhibit
backfill from entering the chamber.
[0058] The first louver 142a and the interior louvers 142b, 142y
includes a respective lip 144a, 144b, 144y along the inside of
their top surfaces 146a, 146b, 146y. The top louver surfaces 146
run parallel to the base flange 30. The lips 144 extend above the
top louver surface 146 by a first distance d1 and are separated
from the next louver by a second distance d2.
[0059] The bottom surfaces 48 of the interior louvers 142b, 142y
and the top louver 142z run at an angle .THETA.1 relative to the
adjacent top louver surfaces 146a, 146y. The bottom surfaces 148
are thus separated from the prior louver top surface 146 by a third
distance d3. The interior louvers have an inside height of d4,
including the lip, and an outside height of d5. As shown, the
louvers have an inside-to-outside width d6, which is greater than
the thickness of the side wall.
[0060] In a specific embodiment, the chamber wall thickness is
nominally 0.10 inches. For the louvers, d1 is 0.030 inches, d2 is
0.110 inches, d3 is 0.152 inches, d4 is 0.130 inches, d5 is 0.083
inches, d6 is 0.250 inches (including the sidewall thickness) when
measured perpendicular to the arch, and .THETA.1 is 4.0 degrees.
Other dimensions can be substituted to meet other engineering
requirements. For example, although the louver surfaces is offset
and extends from the corrugation side walls by about 0.15 inches,
other approaches to the infiltration structures could be used.
[0061] FIG. 8 is a foreshortened cross-sectional view along line
B-B of FIG. 4. The view shows a representative horizontal
cross-section of a peak and valley corrugation.
[0062] The particular arc of the peak corrugation 40 is
continuously variable from the bottom of the corrugation to the
crest. The peak corrugation is, in particular, a linear blended
surface between the horizontal plane (at the base flange 30) and
the vertical plane (at the crest of the chamber arch). More
specifically, the arc is only measurable as a radius (but still
variable) if the corrugation is sectioned perpendicular to the
chamber's arch. In the illustrated view, the curve is an incidental
ellipse. Also, when sectioned horizontally as shown, the thickness
of the louvers is variable. If a cross-section were taken
perpendicular to the chamber arch (i.e. passing through the center
axis 5 (FIG. 1)), then the louver thickness would be equal to d6
(FIG. 7).
[0063] The laterally curving surfaces of the corrugations has a
radius that becomes smaller with an increase in elevation, starting
at the bottom on a lateral plane and ending at the top on a
vertical plane. That change in dimensions results in corrugations
having portions that are larger at the bottom and smaller at the
top. The larger corrugation portion at the bottom can provide
greater strength for resisting backfill. The radius blends into the
side walls of the corrugations, which can be slightly angled for
strength purposes. Again, note that the louvers protruded from the
corrugations.
[0064] Particular chambers can have a peak corrugation profile that
is similar to a successful pipe profile disclosed on U.S. Pat. No.
6,644,357 to Goddard, the teachings of which are incorporated
herein by reference. Unlike a pipe, however, the chamber does not
require a fixed diameter. Instead, the particular peak corrugations
have an arch-shape that is larger in diameter at the base than at
the crest.
[0065] As shown in FIG. 8, the peak corrugations 40 and the valley
corrugations 50 have respective louvered opening features 140, 150.
Note that the louver features is a formed feature that follows the
contour of the corrugations. This shaping of the louvers increases
the amount of open area provided at the corrugations.
[0066] At the peak corrugation 40, the louver feature 140 includes
a protruding frame 148 and center support member 149. In
particular, the approximate amount of sidewall material removed to
form the open areas between the louvers in the peak corrugation is
replaced by material in the frame 148 and center support 149. The
valley corrugations 50 have similar louver features 150. Although
the valley corrugations 50 have center supports 159, outer support
is provided by the sidewall itself 158. Also shown is a brace 157
for base of the valley louver center support 159. In a particular
embodiment, the frame 148 and center supports 149, 159 have a
thickness equal to the thickness of the louvers, d6 (FIG. 7).
[0067] In a particular embodiment of the above-described leaching
chamber 1, the leaching chamber has a total length (TL) of 63.16
inches, a laying length (LL) of 60.00 inches, a width (W) of 34.50
inches, a height (H) of 13.00 inches, and a height to the highest
louver opening (h) of 7.13 inches. The overall chamber weighs about
15.3 pounds. With respect to the above-referenced U.S. Pat. No.
6,644,357, the peak corrugations have a 36-inch pipe profile at its
base and transitions to a 24-inch pipe profile at its crest.
[0068] Further dimensions are given in Table 1, below.
TABLE-US-00001 TABLE 1 Chamber Volume (Lay Length) 13896.4 Sq. In.
Total Bottom Area 2070.00 Sq. In. Open Bottom Area 1747.32 Sq. In.
Footprint Area 322.68 Sq. In. Sidewall Infiltration Surface Area
462.77 Sq. In. Chamber Volume per Linear Foot 2779.28 Cu. In. Total
Bottom Area per Linear Foot 414.00 Sq. In. Open Bottom Area per
Linear Foot 349.46 Sq. In. Footprint Area per Linear Foot 64.54 Sq.
In. Sidewall Infiltration Surface Area per Linear Foot 92.55 Sq.
In. Total Infiltration Surface 442.02 Sq. In.
[0069] A leaching chamber manufactured in accordance with the above
disclosure (ARC-36 H-10) has been compared with samples of other
low-weight commercially-available leaching chambers. The results
between the ARC-36 H-10 embodiment and the Quick 4 chamber from
Infiltrator Systems, Inc. are summarized in Table 2, below:
TABLE-US-00002 TABLE 2 ARC-36 H-10 Quick 4 LL .times. W .times. H
60.0 .times. 35.5 .times. 12.5 46.5 .times. 33.5 .times. 13.0
inches inches Weight (lbs) 15.3 12.5 3% Deflection 1320 lbs 254 lbs
6% Deflection 3446 lbs 1015 lbs 12% Deflection 5573 lbs 5287 lbs
25% Deflection 2573 lbs 3247 lbs Maximum Load 5573 lbs 6509 lbs
Failure Point 12.0% 19.6% Sidewall Thickness 0.091-0.099 inch
0.092-0.106 inch Range Note that the disclosed ARC-36 chamber
resists loads much better than the competing products. It requires
5 times the load of the Quick 4 chamber to deflect 3% and over 3
times the load to deflect 6%. For the ARC-36, the first failure
point occurs when the crown buckles. In the Quick 4 product, there
are preliminary failures before the chamber fails. The distinctions
are illustrated by load/deflection curves.
[0070] FIG. 9A is a load/defection curve for the ARC-36 chamber of
Table 2. The curve was plotted from actual measurement data. Note
that up until the failure point A1 at 5573 pounds, the
load/deflection curve is smooth. Even after the failure point, the
curve remains smooth before leveling off. This indicates that, even
after buckling, the chamber remains as a integral structure.
[0071] FIG. 9B is a load/deflection curve for the Quick 4 chamber
of Table 2. Again, the curve was plotted from actual measurement
data. The Quick 4 chamber fails at a load of 6509 pounds at point
Q1, but there is an earlier break at about 5500 pounds at point Q2.
After the main failure, the curve falls off sharply and reveals
further breaks at least at points Q3, Q4, Q5, Q6, and Q7,
indicating that the chamber has lost structural integrity.
[0072] While the above-disclosed leaching chamber operates well for
its intended purpose, it requires a trench width of at least 36
inches. Some localities require narrower trenches, such as 24
inches or 18 inches. As narrow chambers where designed, it was
found that the location of the inspection port in the body of the
chamber tended to weaken the chamber. To solve that problem, the
inspection port was moved from the body of the chamber to the
ends.
[0073] FIG. 10 is a perspective view of a leaching chamber having
inspection port ends. Like the leaching chamber 1 of FIGS. 1-8, the
leaching chamber 100 has an open bottom and is generally arch
shaped with a center axis 105. The chamber has a total length TL',
a width W', and a height H'. The leaching chamber 100 includes a
first end flange 110 at a first end and a second end flange 120 at
a second end. The first and second end flanges 110, 120 are
complementary so that the first end flange 110 of one chamber can
mate with the second end flange 120 of an adjacent chamber.
[0074] The first end flange 110 includes a first inspection port
structure 112 at the crest of the arch and the second end flange
120 includes a second inspection port 122 at the crest of the arch.
Access to the interior of an installed leaching field is attained
by cutting out one of more inspection ports. It should be
recognized that the first inspection port 112 functions as a post
and the second inspection port 122 functions as a dome in a
post-dome configuration. That is, when two chambers are mated, the
second inspection port 122 of one chamber overlaps the first
inspection port 112 of another chamber.
[0075] Because the inspection ports are circular structures, the
mated chambers can pivot about the mated inspection ports 112, 122
though a fixed angular range.
[0076] FIG. 11 is a side view of the leaching chamber 100 of FIG.
10. Except for structural differences to accommodate the inspection
ports, the chamber 100 is similar to the chamber 1 of FIGS. 1-8.
The laying length LL' of the chamber is defined as the longitudinal
distance between the centers of the first inspection port 112 and
the second inspection port 122.
[0077] Note that the inspection port structure 112 at the first end
is disposed on a larger length first end flange 110 as compared to
the leaching chamber of FIG. 1. That additional span if repeated at
the opposite end could introduce a weakness into the joint. To
counteract that possibility, there is a peak corrugation at the
second end that is intersected by the second inspection port
structure 122. That corrugation adds strength to the joint without
the need for a structural rib.
[0078] FIG. 12 is a top view of the leaching chamber 100 of FIG.
10. Note that the first end 132 of the base flange 130 is contoured
to receive a second end 134 of another base flange 130. The
received second end is held in place by tabs 116 extending from the
first end flange 110.
[0079] FIGS. 13A-13B illustrate the interconnection of adjacent
leaching chambers of FIG. 10. Note that assembly is similar to that
shown in FIGS. 6A-6B, except that the post 12 is replaced by a
first (overlapped) inspection port 112 and the dome 22 is replaced
by a second (overlapping) inspection port 122. To access the
interior of the chamber, the mated inspection ports 112, 122 are
cut out.
[0080] In a particular embodiment of the above-described leaching
chamber 100, the leaching chamber has a total length (TL') of 67.25
inches, a laying length (LL') of 60.00 inches, a width (W) of 22.00
inches, a height (H) of 11.623 inches. Note that the resulting
22-inch chamber is nearly as tall as the previously described
36-inch chamber, which results in a more favorable arch
profile.
[0081] It should be understood that the dimensions given above are
approximate or nominal dimensions, which can vary due to changes in
material properties or manufacturing techniques. The performance of
the manufactured product can be enhanced by designing for even
distribution of plastic throughout the part. In a particular
embodiment, the actual sidewall thickness varies by less than 10%
of the maximum thickness.
[0082] The chambers are typically shipped from a factory to a
distribution center by being stacked on pallets. It is advantageous
to stack many chambers on a single pallet. The rigidity of prior
art leaching chambers can cause breakage during transport. It is
not unusual for 10% of prior art chambers on a pallet to be cracked
during shipment. The flexibility and profile of the above-disclosed
chambers allows them to be more reliably transported, and in
greater numbers per pallet.
[0083] FIG. 14 is a cross-sectional diagram of nested chambers
taken along line C-C in a valley corrugation of FIG. 4. As shown,
two chambers 1A, 1B are stacked, such as for shipping or storage.
Each valley corrugation includes a pair of stacking columns 162A,
162B extending downward from the underside of the corrugation and a
pair of stacking pockets 164A, 164B on the topside of the
corrugation. As shown, the stacking columns 162A, 162B are tube
shaped and can be longer than the distance separating the surface
of the peak corrugations from the surface of the valley
corrugations. The stacking pockets 164A, 164B are delimited from
the corrugation surface by a rail 166A, 166B formed into the
corrugation. When stacked, the bottom of the top stacking column
162B rests in a respective pocket 164A of the next lower chamber
1A, with the rail 166A guiding and holding the column 162B in the
pocket 164A.
[0084] Because the arch shape and corrugations decrease in size
away from the base, the chambers can be closely stacked. The
stacking pockets 164 guide the columns 162 so that they are
vertically aligned. With a pallet suitably constructed to transfer
the column load to the pallet, a stack of at least 60 chambers can
be shipped without damage. Even if the load is not directly
transferred, the only chamber that typically suffers damage is the
bottom chamber, which carries the load of all chambers above it,
and generally only when the plastic is exposed to sufficient heat
to weaken its stacking pocket 164.
[0085] The flexibility of the above-disclosed chambers also reduces
the risk of damage due to rough handling of individual chambers.
Instead of resisting twisting and bending forces, which can break
prior art chambers, the above-disclosed chambers move with the
forces by flexing. While the corrugations themselves are strong,
the chamber can flex around its center axis. In particular, the
chamber can be easily twisted so that the opposing ends are at
about 45 degrees relative to each other. Once the forces are
removed, the chamber returns to its nominal shape.
[0086] While particular embodiments of the leaching chambers are
injection molded from high density polyethylene (HDPE), other
manufacturing techniques can be used. In addition, the leaching
chambers can be fabricated from another suitable polymer, such as
polypropylene, or another material, such as concrete, metal, or
ceramics, or combinations of materials.
[0087] While this invention has been shown and described with
references to particular embodiments, it will be understood by
those skilled in the art that various changes in form and details
may be made to the detailed embodiments without departing from the
scope of the invention as defined by the appended claims.
* * * * *