Note: Descriptions are shown in the official language in which they were submitted.
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Title of the Invention
A greywater diversion and hair catcher assembly for baths that is comprised
of the novel assembly of a hair catcher mesh cup, a two-port valve, a direct-
drain waste-overflow assembly, and an indirect-drain waste-overflow
assembly.
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Prior Art
2915875 October 1975 Olson
5147532 September 1992 Leek, Jr.
5160606 November 1992 Morrissey et al.
6328882 December 2001 Rosenblatt
6969460 November 2005 Bertram
Inventor
Christopher Adam McLeod
28 Imperial St., Toronto, ON Canada M5P 1C2
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Background of the Invention
Bath design across the world shares one characteristic, a variously shaped
vessel for holding water and bather concurrently. Bath design differs in how
water is put in; bath design differs again in how water is safely conducted
from the vessel to a sewer or other water management system. Water
egressing from the bath vessel is widely called "greywater", implying that,
although the water may contain mild impurities, it is a valuable resource
that can be reused in applications as diverse as cooling and garden
irrigation.
This invention concerns a plumbing fixture fitting for baths and other vessels
that allows for the diversion of this greywater upon demand, safely. This
requires the integration of four critical features, (i) a hair catcher to
capture
fibers from entering the drain fitting, (ii) an on-demand diversion function,
(iii) a three-port entry-exit system comprised of one entry port from the
vessel drain and two exit ports, one to the primary sanitary drainage system
and one to the greywater utilization system and (iv) a backflow capacity
such that if and when the greywater usage system fails partially or entirely,
the excess greywater will flow back to the primary sewer.
Although many an American household eager to save water for economic
and environmental reasons has incorporated some of these features in
home-made greywater diversion schemes, these systems are prone to
failure, flooding, and even cross-contamination risks. Further, although
commercial greywater diverters do exist outside North American for post-
trap applications, these devices are not suitable for pre-trap applications
owing to the inability to install these devices between the bath and the floor
or traps beneath the floor as well as other problems arising from their design
in ignorance of North American standard plumbing fittings.
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Brief Summary of the Invention
This invention combines standard plumbing fixture fittings with a hair
catcher and a two-port valve to effect a safe means of diverting greywater
from a bath. The hair catcher acts to keep fibers out of the drainage system
and/or greywater utilization system. The two-port valve is comprised of a
variable diversion device such as a hand-turned ball valve or remotely
operated solenoid valve that allow for partial or entire diversion of the
waste
water. A full-port valve is recommended to avoid restriction of the inner
diameter of the drainage assembly. The invention of this device comes in
the novel combination of two standard waste overflow bath fittings with the
hair catcher and the valve to effect the safe diversion of greywater. The
first
fitting is a direct waste overflow assembly, which allows water to egress
directly and vertically down to a waste system pipe located beneath the bath
drain waste hole, wherein the bath overflow acts both as a vent and as a
flooding control system. The second fitting is an indirect waste overflow
assembly, which incorporates an elbow to horizontally direct drain water
away from the bath drain waste hole to a sanitary tee fitting distal from the
bath drain hole and approximately vertically beneath the overflow waste
elbow attached to the side of the bath. By interconnecting these various
fittings, a new device is created which allows for the safe diversion of
greywater. A further embodiment adds a bleed between the two traps
attached to the dual exit ports of this assembly.
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Brief Description of the Drawing
The invention is pictured in Fig. 1 attached to a standard bath (1). A direct
drain tee fitting (3) is attached the bath by means of sealing rings and nuts,
and contains a hair catcher wire mesh insert (2) that fits in the bath drain
waste hole strainer component of the fitting. This wire mesh insert allows
the closure of a plug without requiring removal of the wire mesh. A two-port
valve (4) is operated to fully or partially prevent or allow the passage of
greywater through a trap (5) eventually leading via port (6) to a greywater
utilization system. Should this system be fully or partially unable to accept
the full flow of the greywater draining from the bath, or if the user has
adjusted the valve (4) to fully or partially block the egress of greywater
from
the bath, the drain water would then travel horizontally along the horizontal
transverse connection pipe (7) to flow through a sanitary tee fitting (10).
This fitting is also connected to a trap (8) and then leads via an exit port
(9)
to a primary sanitary drainage system. Note that the bath overflow (12) has
two roles, the first as an air vent to enable the egress of drain water around
either trap, and the second as an optional waste water drain (leading to the
same chosen trap or traps) in the case of bath overflow where the waste
drain has been blocked or stoppered with a plug.
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Detailed Description
Olsen (3915857) in 1975 started the greywater diversion patent stream with
his highly complex tank and filter system. More than a diversion device,
the patent describes a greywater utilization system, with various risks that
would not be allowed in modern plumbing fixtures. In contrast, the
invention described in this application makes no comment upon, and
operates independently from, the greywater utilization system attached to
the exit port of the diverter-side trap of the assembly. The invention in this
application merely serves as a safe means of diverting greywater to that
utilization system.
Similarly, Leek Jr. (5147532) patented a device whereby greywater is fed to
UV device for sterilizing greywater in a tank for direct re-use. The critical
defining question for such systems is what occurs when there is too much
greywater for the greywater usage system to manage. Although an
overflow may be incorporated within a system such as Leek's, if the system
fails, the overflow may fail too. It is preferable to separate out the safety
overflow function upstream to the greywater utilization system in order to
avoid backup of greywater to the bath fixture. A multiplicity of greywater
utilization patents suffer from this basic flaw, including De Simone et al.
( 5160606, 1992), Morrissey et al. (5403498, 1995), and Rosenblatt
(6328882, 2001).
Bertram (6,969,460) led the way out of this morass with his design of a
valve that diverts greywater fully or partially away from the primary sanitary
drain system, catches hair with a mesh insert, and finally allowing for
backflow to the primary drain system should the greywater utilization
system be fully or partially blocked. His device, however, is restricted in
several aspects. These restrictions, and how they are addressed by the
invention in this application, are described in the following paragraphs.
(i) Bertram's device cannot be physically attached to a typical North
American bath. There is no space for a large vertical assembly between the
bath and the floor, or again between the floor and the trap below the bath.
The invention mentioned in this application requires only the cutting of an
additional 1.5" diameter hole in the floor beneath the bath, and the
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installation of an additional trap in the ceiling below the floor, both of
which
must be possible for virtually all given North American bath installations.
(ii) Bertram's device therefore must be located post-trap. The question of
where this might be can be problematic. The device would have to be fixed
to a wall very strongly to allow for regular cleaning of the hair catcher by
opening and then forcing closed the sealed access cap. If this device is
located outside, there is the further possibility of freezing or other damage.
(iii) Regular cleaning of the hair catcher is a difficult task in Bertram's
device.
Particularly if previous owners of a house had installed the greywater
diverter as per Bertram's design, the new owners may be entirely oblivious
to the necessity of regular cleaning, with the result that the new owners may
think their greywater is being diverted to the greywater utilization system,
but in fact it is backflowing down the primary sewer. In contrast, with the
invention under application, the hair catcher is located in the bath drain
hole.
When the hair catcher needs cleaning, it is immediately obvious to the bath
or shower user as drainage from the bath will be impeded. And it is much
easier to clean since no access panel with pressure head requirements must
be opened somewhere in the floor below.
(iv) If the greywater utilization system blocks up, this has the effect of
trapping water from between Bertram's device and the trap supplying it (if
the device is installed downstream of the trap) or between Bertram's device
and the bath drain (if the device is installed upstream of the trap). This
will
give rise to odor as the water support bacterial growth. In contrast, the
device in this application can be shut off completely with the two-way valve,
allowing for the entire device to revert to an industry standard indirect
waste
overflow, avoiding odor problems associated with stagnation of pooled water.
For this and other reasons, although Bertram's device pointed the way to
separating greywater diversion devices from the greywater utilization
systems that supply it, its design contains a number of flaws that thwart its
design intent. In contrast, the design in the application is based on a novel
combination of traditional bath fittings, and avoids these problems.
Finally, there is the consideration that if a user were to keep their
greywater
diversion valve open constantly, the trap connecting the assembly to the
primary sanitary drain may dry out and allow the ingress of sewer gases into
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the house. This potential risk is solved by interconnecting the two traps of
this assembly by mean of any variety of connection tubes and fittings.
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