U.S. patent application number 12/527983 was filed with the patent office on 2010-05-06 for sewer overflow relief device.
Invention is credited to Gregory John Williamson.
Application Number | 20100108159 12/527983 |
Document ID | / |
Family ID | 39709561 |
Filed Date | 2010-05-06 |
United States Patent
Application |
20100108159 |
Kind Code |
A1 |
Williamson; Gregory John |
May 6, 2010 |
SEWER OVERFLOW RELIEF DEVICE
Abstract
A sewer overflow relief device for mounting at a top end of a
sewer overflow relief pipe includes a top cover having at least one
outside air intake and an air flow control mechanism for
controlling the flow of outside air into the sewer overflow relief
pipe. In use, the device prevents outside water from entering the
sewer and the device may be ejected from the sewer overflow relief
pipe by sewage pressure pushing against the device, thereby
allowing the sewer overflow relief pipe to overflow.
Inventors: |
Williamson; Gregory John;
(Victoria, AU) |
Correspondence
Address: |
NOVAK DRUCE DELUCA + QUIGG LLP
1300 EYE STREET NW, SUITE 1000 WEST TOWER
WASHINGTON
DC
20005
US
|
Family ID: |
39709561 |
Appl. No.: |
12/527983 |
Filed: |
February 21, 2008 |
PCT Filed: |
February 21, 2008 |
PCT NO: |
PCT/AU2008/000234 |
371 Date: |
October 16, 2009 |
Current U.S.
Class: |
137/493 |
Current CPC
Class: |
E03F 5/08 20130101; F16K
24/06 20130101; E03F 5/12 20130101; Y10T 137/7771 20150401 |
Class at
Publication: |
137/493 |
International
Class: |
E03F 5/042 20060101
E03F005/042 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 2007 |
AU |
2007900884 |
Claims
1.-9. (canceled)
10. A sewer overflow relief device for mounting at a top end of a
sewer overflow relief pipe, the device comprising: a top cover
having an upper surface, the upper surface having at least one
outside air intake; and air flow control means for controlling the
flow of outside air into the sewer overflow relief pipe; wherein,
in use, the device prevents outside water from entering the sewer
and the device may be ejected from the sewer overflow relief pipe
by sewage pressure pushing against the device, thereby allowing the
sewer overflow relief pipe to overflow.
11. The sewer overflow relief device according to claim 10, wherein
the upper surface is a dome.
12. The sewer overflow relief device according to claim 10, wherein
the air flow control means comprise a one-way air valve having an
upstream side in fluid connection with the at least one outside air
intake and having a downstream side in fluid connection with the
sewer overflow relief pipe; wherein the valve is oriented, when the
device is oriented in an in-use orientation, with the upstream side
at a lower level than the downstream side; and wherein the valve is
operable to allow passage of air when pressure on the downstream
side is lower than on the upstream side, whereby outside air is
admitted into the sewer overflow relief pipe.
13. The sewer overflow relief device according to claim 10, wherein
the at least one outside air intake is, when the device is oriented
in an in-use orientation, located at a level higher than the level
of the top end of the sewer overflow relief pipe.
14. The sewer overflow relief device according to claim 10, further
comprising a body of circular cross section for insertion into the
top end of the sewer overflow relief pipe, the side walls of the
body being sized to provide a close fitting arrangement with an
internal wall of the top end of the sewer overflow relief pipe so
as to prevent egress of sewer gas; wherein the top cover is fixed
to the body and has the same diameter as the outer diameter of the
top end of the sewer overflow relief pipe, whereby the device is
difficult to manually remove from the sewer overflow relief
pipe.
15. The sewer overflow relief device according to claim 10, further
comprising a float for engaging against the device; wherein, in
use, the device may be ejected from the sewer overflow relief pipe
by sewage pressure pushing against the float.
16. The sewer overflow relief device according to claim 10, wherein
the upper surface is polyhedral.
17. The sewer overflow relief device according to claim 10,
wherein, when the device is oriented in an in-use orientation, the
at least one outside air intake is located in a raised position
higher than the outer perimeter of the top cover.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a device for providing
sewer overflow relief arrangements and to venting of sewers. The
invention is described herein in relation to domestic plumbing but
is not limited to that application only.
BACKGROUND OF THE INVENTION
[0002] Waste water is carried away from buildings and roads via two
different systems. The first is via storm water drains and
channels, which typically discharge directly to a natural body of
water such as a river, estuary or sea. While some rubbish carried
from stormwater may be filtered from the flow by appropriate
screens or grates, the water itself is not treated before
discharge, as it is generally freshwater run-off from rainfall or
storms. The second system is the sewage system, and water or sewage
discharged to the sewage system must be carefully treated by
appropriate processes before the treated water can be discharged
into the environment. Such treatment is expensive.
[0003] The connection of a house or building to the general sewage
system includes provision for dealing with local sewage blockages
or pressure problems. Rather than having a situation where sewage
backs up through an outlet in the home (for example, the toilet),
an overflow relief gully is provided outside, adjacent the home.
This ensures that in the event of a sewage overflow, the overflow
does not incur inside the home. Typically the overflow relief gully
is a grate over a pit, connected to the building's sewage system by
a sewer overflow relief pipe having a water seal created by a
`water trap` or `U-bend` which prevents egress of sewer gas. This
pipe is run as an extension from the sewage pipes under the house
and typically the sink waste water is run to the overflow relief
gully in order to maintain the water seal. A bib tap is also
provided to help maintain the water seal.
[0004] It has become a common practice for builders and landscapers
to channel stormwater run-offs into the overflow relief gully,
instead of to the storm water system. This is because the overflow
relief gully is typically conveniently located near the home (in
order to minimise the length of the extension and distance to run
the sink waste water), and hence is located near surfaces such as
concreted driveways and the like, from which water runs off. The
driveways and the like are deliberately built with a gradient
directing the run-off water to the overflow relief gully. Also,
guttering down pipes can also be run to the overflow relief gully.
This practice is very undesirable, as it increases significantly
the volume of sewage that needs to be treated, and hence the costs
associated with carrying the volume of sewage to a treatment plant,
the number of treatment plants required, and the cost of actually
treating the sewage.
[0005] It is therefore desirable to reduce the volume of sewage
requiring treatment.
SUMMARY OF THE INVENTION
[0006] A first aspect of the present invention provides a sewer
overflow relief device for mounting at a top end of a sewer
overflow relief pipe, the device including: [0007] a top cover
having at least one outside air intake; [0008] air flow control
means for controlling the flow of outside air into the sewer
overflow relief pipe; [0009] wherein, in use, the device prevents
outside water from entering the sewer and the device may be ejected
from the sewer overflow relief pipe by sewage pressure pushing
against the device, thereby allowing the sewer overflow relief pipe
to overflow.
[0010] Preferably, the air flow control means include: [0011] a
one-way air valve having an upstream side in fluid connection with
the at least one outside air intake, and having a downstream side
in fluid connection with the sewer overflow relief pipe; [0012] the
valve oriented, in use, with the upstream side at a lower level
than the downstream side; the valve operable to allow passage of
air when pressure on the downstream side is lower than on the
upstream side, whereby outside air is admitted into the sewer
overflow relief pipe.
[0013] Advantageously, this prevents egress of sewer gas, as sewer
gas tends to rise and therefore is less likely to escape in a
downward direction when the valve is in an open position.
[0014] Preferably, the at least one outside air intake is, in use,
located on a raised portion of the device.
[0015] In a preferred embodiment, the sewer overflow relief device
further includes: [0016] a body of circular cross section for
insertion into the top end of the sewer overflow relief pipe, the
side walls of the body in a close fitting arrangement with the
internal wall of the top end of the sewer overflow relief pipe
thereby preventing egress of sewer gas; [0017] the top cover being
fixed to the body and having the same diameter as the outer
diameter of the top end of the sewer overflow relief pipe, whereby
the device is difficult to manually remove from the sewer overflow
relief pipe.
[0018] If desired, the body and the `pipe` into which the body is
inserted could have any cross-sectional shape, such as a square or
other polygon, provided a close fit is obtained. Optionally, a pipe
end extension or receiving housing can be fitted to extend the pipe
and to receive the device. The end extension or receiving housing
may be of different cross-sectional area or shape to the rest of
the pipe.
[0019] In another preferred embodiment, the sewer overflow relief
device further includes: [0020] a float for engaging against the
device; [0021] wherein, in use, the device may be ejected from the
sewer overflow relief pipe by sewage pressure pushing against the
float. This provides for an even force to be applied to the device,
ensuring that it does not jam or wedge within the pipe. The size
(volume) of the float can also be selected such that the device is
ejected from the pipe earlier than would otherwise occur.
[0022] Advantageously, a device according to the first aspect of
the present invention will prevent most storm water from entering
the sewer via the sewer overflow relief pipe, even where run-off
water has been channelled to the pit or pipe. Even where the level
of water builds up above the outside air intake, water may not pass
the one-way valve except when the downstream (or sewer-side)
pressure is lower than the upstream (or outside-air-side) pressure.
Should this occur, only small amounts of water can enter the sewer
system, and at a low rate.
[0023] Another advantage of a device according to the first aspect
of the present invention is that local venting of the sewer may be
achieved, reducing the need for alternative venting arrangements.
When waste water is flushed down the drains, ventilation must be
provided to allow the flowing waste water to displace the sewer gas
in the drain and then the vacuum which would otherwise form as the
waste water flows down the drain. "Neutral" air pressure is
required in drains, in order to ensure that the gravity operated
system functions correctly. As the waste water passes the sewer
overflow relief pipe junction with the sewer drain, air may be
replenished into the sewer via the one-way valve, which is operated
to automatically open when a low pressure or partial vacuum is
present in the sewer overflow relief pipe, drawing air in through
the outside air intake.
[0024] Yet another advantage of a device according to the first
aspect of the present invention is that it avoids the need to
provide a separate water trap or U-bend to prevent egress of sewer
gas, which is both unpleasant to smell and hazardous. The sewer
overflow relief pipe may be installed as a simple vertical section
of pipe, and its end simply fitted with a device according to the
invention. This reduces both materials and labour involved in
construction. It is not necessary to provide an extension from the
pipes running under the house to adjacent the external wall, as the
overflow relief pipe may be located near the property boundary, and
simply be a vertical extension running from the pipe connecting the
house to the public sewer. Nor is it necessary to run the sink
waste water or provide a bib tap to the overflow relief gully.
Furthermore, by locating the overflow relief pipe remote from the
external wall of the house, the temptation for builders or
landscapers to deliberately channel storm water or other run-offs
to the overflow relief gully is much reduced. As mentioned above, a
pipe extension or receiving housing can be fitted to extend the
overflow relief pipe, or the pipe may simply end without an
extension or other fitting.
[0025] As storm water will not drain effectively via the sewer when
the sewer overflow relief pipe is fitted with the device, and as
the device is tamper resistant (and also necessary to prevent sewer
gas egress and smells), builders, landscapers and the like will be
motivated to ensure stormwater run-off is appropriately directed to
stormwater drainage points (typically near the boundary of a
property). Hence, the volume of sewage requiring treatment is
dramatically reduced.
[0026] A second aspect of the present invention provides a sewer
overflow relief device for mounting at a top end of a sewer
overflow relief pipe, the device including: [0027] a top cover; and
[0028] wherein, in use, the device prevents outside water from
entering the sewer and the device may be ejected from the sewer
overflow relief pipe by sewage pressure pushing against the device,
thereby allowing the sewer overflow relief pipe to overflow.
[0029] A device according to the second embodiment of the invention
is useful for retro-fitting situations, where venting of the sewer
is provided by existing arrangements, and sewer gas egress is
prevented by existing water traps or U-bends.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Other features and advantages of one or more preferred
embodiments of the present invention will be readily apparent to
one of ordinary skill in the art from the following written
description with reference to and, used in conjunction with, the
accompanying drawings, in which:
[0031] FIG. 1 shows a top view of a device according to a preferred
embodiment of the present invention;
[0032] FIG. 2 shows a cross-sectional side view of a device
according to the embodiment of FIG. 1, along the line A-A;
[0033] FIG. 3 shows another top view of a device according to the
embodiment of FIG. 1 positioned in a pipe;
[0034] FIG. 4 shows a cross-sectional side view of a device
according to the embodiment of FIG. 3, along the line B-B;
[0035] FIG. 5 shows a sectioned top perspective view of a device
according to another embodiment of the invention, along the line
A-A;
[0036] FIG. 6 shows a schematic plan view of a house having a
sewage system incorporating a device according to an embodiment of
the invention; and
[0037] FIG. 7 shows a schematic plan view of a house having a
traditional overflow relief gully.
DESCRIPTION OF PREFERRED EMBODIMENT
[0038] FIG. 1 is a top view of a device according to a preferred
embodiment of the present invention together with a pipe end
extension or receiving housing. It shows a top cover 30 having an
outer diameter 34. The top cover 30 has four outside air intakes
36. As may be seen in FIG. 2, (which is a cross-sectional view of
the embodiment taken along the section line A-A as shown in FIG. 1)
the top cover 30 has an upper surface which is a dome 32. The
device further includes a body or housing 20, an insert 60 and air
flow control means, being a one way valve 72 having an outer ring
73. A float 56 also resides within the housing 20.
[0039] The housing 20, insert 60 and top cover 30 are assembled
together in order to form an air path through which outside air is
drawn through outside air intake 36, through conduit 64 of insert
60 into lower chamber 80 and then to sub-chamber 82. Lower chamber
80 is formed by housing 20 and insert 60. The path taken by air is
shown by the heavy black arrows. When one-way valve 72 is in a
raised position (not shown), air passes from lower chamber 80
through valve 72 into upper chamber 90. As shown in FIG. 2, the
housing 20 includes support members 21 which support the insert 60.
These support members 21 define a sub-chamber 82 of lower chamber
80.
[0040] The valve 72 is only raised when the air pressure in upper
chamber 90 is lower than the pressure in lower chamber 80. As may
be seen in FIG. 4, (which is a cross-sectional view of the
embodiment taken along the section line B-B as shown in FIG. 3),
the device 10 is installed at the end of pipe 50. The device may be
installed directly in the pipe (not shown) or be received by a pipe
end extension 120. Air passes from upper chamber 90 through housing
conduit 16 to the sewer pipe 50--chamber 90 is in fluid
communication with the sewer. This arrangement allows for the
venting of the sewer overflow relief pipe 50 but prevents egress of
sewer gas from the sewer through the end of the pipe 50, which is
wholly blocked by the sewer overflow relief device 10. It is
therefore not necessary to provide a separate water seal such as a
`water trap` or `U-bend`.
[0041] Air can only pass in one direction through the sewer
overflow relief device 10--that is outside air may pass into the
sewer. Water cannot pass into the sewer overflow relief device
except in the relatively rare circumstances that one- way valve 72
is in a raised position (i.e. under the same circumstances in which
air may be passed into the sewer overflow relief pipe). Hence,
stormwater and the like does not pass into the sewerage system and
hence the volume of sewerage required to be treated is reduced.
[0042] The lower chamber 80, which is on the upstream side of
one-way valve 72, is in fluid communication with outside air, via
outside air intake 36 and conduit 64. By relying upon negative
sewer pressure to raise one-way valve 72 in order to admit air into
upper chamber 90 and, where neutral pressure is obtained, relying
upon gravity to close one-way valve 72, the admittance of any water
that may be present into the sewer is severely restricted. One-way
valve 72 is desirably manufactured from a material heavier than
water. Therefore, if chamber 80 is filled with water, the valve 72
is not raised by normal water pressure--only by negative pressure
in chamber 90. As the operation of the venting valve is infrequent,
a very low volume of water may be admitted.
[0043] Storm water and other water is further deterred from
entering the device 10 as the outside air intake holes 36 are
raised by being situated part way up dome 32. Where water does
enter through these holes, it may pool in lower chamber 80 and on
relatively rare occasions be passed through to chamber 90 (as
described above). However, this is a very small volume of water
when compared to the volume of water typically passed into the
sewer system from stormwater run off.
[0044] An optional pipe end extension or receiving housing 120 may
be provided at the end of pipe 50. The device 10 is received by or
fits inside extension/housing 120 (or optionally may be integrally
formed) and the raised dome section 122 of the housing 120, which
extends above the local ground level (or bottom of a pit) further
prevents storm water from pooling near or entering intake holes
36.
[0045] The extension/housing 120 may also serve as an `adaptor` for
the device 10, allowing retrofitting of the device 10 into
finishing collars (also known as mound collars) (not shown)
installed at pipe ends (usually for supporting grates). It can be
used with terracotta, PVC and iron finishing collars.
[0046] The extension/housing 120 has the `same` internal diameter
as pipe 50 and is positioned to rest upon the end of the pipe 50.
Preferably, the extension/housing 120 has a resilient structure or
is of resilient material, such that it may be readily installed in
a retrofit situation and allows for ease of insertion of the
device.
[0047] The extension/housing 120 shown in FIG. 4 includes an angled
outer rim 124 (forming an `arrow` in cross-section) which may be
useful in a retrofit situation as it assists in guiding for
installation and increases the resilient flexibility in this area.
An O-ring may be provided to rest on the base of the `arrow` to
seal to a finishing collar.
[0048] In the event that the sewer pressure builds such that the
sewer overflow relief device is required to operate by overflowing,
in order to prevent overflow at a location inside the house, the
float 56 pushes against housing 20 thereby causing the entire sewer
overflow relief device 10 to pop out or eject from the sewer
overflow relief pipe 50 (or from extension/housing 120). This
allows the sewer to overflow as necessary from the overflow relief
pipe 50. Once the situation has been corrected or resolved, the
overflow relief device 10 may be simply re-installed into the pipe
50.
[0049] As the top cover 30 has an outer diameter 34 which is the
same or lesser diameter than the outer diameter of pipe 50 (the
embodiment of FIG. 4 has outer diameter 34 the `same` as the inner
diameter of pipe end extension 120 of pipe 50), it is very
difficult for the general public or indeed a workman to tamper with
the sewer overflow relief device 10. A special tool may be required
to remove the device--potentially being inserted through an outside
air intake hole 36. A further motivation for avoidance of tampering
is the fact that the sewer overflow relief pipe 50 does not need to
have been provided with a water seal and hence removal of the
overflow relief device 10 will result in egress of sewer gas--which
both smells and is hazardous. Therefore, attempts to alter the
device or force it into a permanently `open` valve position, to
allow storm water to drain to the sewer, are unlikely.
[0050] As may be seen in FIGS. 2, 4 and 5, the various parts of the
sewer overflow relief device 10 according to embodiments of the
invention may be fixed and sealed together by provision of sealing
O-rings 38 and 42, which seal the top cover 30 to the insert 60 and
housing 20. The device 10 is closely fitted inside
extension/housing 120 or pipe 50, (once installed). The outer
diameter of housing or body 20 is closely matched to the inner
diameter of the receiving housing 120 or pipe 50. Optional holes
(not shown) in the wall 22 may enable both a saving of material and
a degree of resilient movement in the housing 20, to enable ease of
installation. Depending on the characteristics of the material
selected, the holes may, or not, be appropriate in some
embodiments. Preferably the device is manufactured from PVC. O-ring
28 seals the sewer overflow relief device 10 to the receiving
housing 120 or to the sewer overflow relief pipe 50. The insert 60
may be affixed to top cover 30 via screws engaged through screw
holes 46, 66, 26. The distance through which one-way valve 72 may
travel is regulated by valve stop 44 provided on top cover 30.
One-way valve 72 rests in its closed or lowered position upon
insert 60, however, the precise arrangement may be varied and it
could also rest upon the housing. In a less preferred embodiment
(not shown) the device is fitted outside the pipe 50 rather than
inside and alternative tamper proof features may be provided.
[0051] As is shown in FIG. 6 which is a schematic plan view, the
present invention allows for an arrangement in which (when compared
to FIG. 7, a schematic plan view of prior art arrangements) an
extension pipe 112 and overflow relief gully 110 may be omitted.
Sewer main 100 is connected at sewer connection point 104 to a
private property 102 having a building 106. A venting arrangement
108 is provided at the remote end of the building 106 (the
additional venting provided by the present invention provides
localised venting). The overflow relief pipe may be provided as a
vertical pipe at the sewer connection point 104, thereby further
removing the temptation for stormwater to be drained towards it as
it is remote from the house and from concreted driveways, paths,
guttering down pipes and the like.
[0052] As the present invention may be embodied in several forms
without departing from the spirit of the essential characteristics
of the invention, it should be understood that the above described
embodiments are not to limit the present invention unless otherwise
specified, but rather should be construed broadly within the spirit
and scope of the present invention as defined in the appended
claims. Various modifications and equivalent arrangements are
intended to be included within the spirit and scope of the present
invention and appended claims.
* * * * *