Title:
Self-ventilating toilet
Kind Code:
A1


Abstract:
An improvement to standard toilet bowls implemented during manufacturing at almost no additional cost, whereby malodor can be vented directly from the toilet bowl into the drainage system. A dedicated auxiliary duct is incorporated in the toilet bowl connecting a circular opening at its top behind the seat with the inside air pocket behind and above the siphon. The opening is blocked with a replaceable tight-fitting plastic plug if the self-venting feature is not required. A low voltage electric fan (6-12V) is retrofitted behind the toilet seat and secured thereto at the seat anchor holes, with a flat intake nozzle fitting under the rear end of the toilet seat, and a discharge tube connected to the aforementioned opening behind the toilet seat. Malodors are sucked by the air fan directly from the toilet bowl through the intake nozzle, and are vented through the discharge tube into the drain system behind the siphon. A biased one way flapper and a mesh system insect screen are deployed inside the exhaust duct (or alternatively a secondary water trap is deployed inside the auxiliary duct) to prevent ingress of malodor and insects from the drains when the air fan is dormant. A switch to actuate the air fan (either manual, or self actuating/de-actuating) and a timing device are incorporated in the system.



Inventors:
Abunameh, Hani A. (Amman, JO)
Application Number:
11/893757
Publication Date:
02/19/2009
Filing Date:
08/17/2007
Primary Class:
International Classes:
E03D9/052
View Patent Images:
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Primary Examiner:
LOEPPKE, JANIE MEREDITH
Attorney, Agent or Firm:
ABELMAN, FRAYNE & SCHWAB (NEW YORK, NY, US)
Claims:
1. A self ventilating toilet bowl (pedestal or cantilever) made homogeneously of any suitable material, with a rim, a siphon, flush water supply system, toilet seat and cover, and connection to the drainage system, the toilet bowl incorporating an auxiliary cylindrical air duct connecting a circular opening in the toilet bowl's top behind the seat to one side, either left or right, of the flush water duct, causing no obstruction thereto, with another circular opening of the same diameter in the top side of the air chamber inside the toilet bowl behind and above the siphon.

2. The self ventilating toilet bowl as defined in claim 1, wherein the auxiliary cylindrical air duct and the circular opening in the toilet bowl's top are omitted, connection with the air chamber inside the toilet bowl behind and above the siphon being maintained directly through the second circular opening deployed on the upper rear side of the toilet bowl below the rim.

3. The self ventilating toilet bowl as defined in claim 1, wherein a replaceable plastic plug with a rounded top and a 25 mm-long shank and a rubber sleeve is provided to fit perfectly and securely into the external circular openings.

4. A centrifugal air suction fan driven by a low voltage DC electric motor (6-12V battery or mains operated through a transformer) contained within a robust waterproof casing (plastic or metal) of measurements suitable to fit between the rear end of the toilet seat and the flush tank, and to provide low-noise and efficient venting of the toilet bowl, the casing being homogeneously provided with a circular inlet opening near its front centre; a discharge tube at its upper tangent; a plastic grating which fits securely at the inlet opening of the air fan to protect the air fan impeller; and an indented tongue and a threaded hole at its rear center for aligning and attaching the unit to a base plate.

5. The centrifugal air suction fan unit defined in claim 4, further comprising a detachable hollow intake nozzle made of plastic or metal with a flat end of maximum dimensions to fit between the toilet bowl rim and the toilet seat and between the toilet seat anchor holes, the other end being circular to fit securely onto the air fan's inlet opening.

6. The centrifugal air suction fan unit defined in claim 4, further comprising an L-shaped robust plate with one side (vertical) having a hole, and a groove indentation matching substantially with the tongue, and the threaded hole for the positioning and attachment of the air fan casing, the other side being provided with anchor holes for attaching the assembled air fan to the toilet bowl at the seat's anchor holes.

7. The centrifugal air suction fan unit defined in claim 4, further comprising a replaceable biased, in the closed position, air flapper which fits perfectly and securely into the air fan's discharge tube to stop the ingress of foul gases from the drains when the air fan is dormant.

8. The centrifugal air suction fan unit defined in claim 4, further comprising an elbow duct, plastic or metal, connecting to the air fan's discharge tube.

9. The centrifugal air suction fan unit defined in claim 4, further comprising a first straight duct, connected at one end to the elbow duct, and with another duct which fits inside the exhaust opening in the toilet bowl.

10. The centrifugal air suction fan unit defined in claim 4, further comprising a second a straight duct connecting with the first straight duct, with an integral external ring collar to limit penetration, and a rubber sleeve at the other end, fitting perfectly and firmly into the second air exhaust opening in the toilet bowl.

11. The centrifugal air suction fan unit defined in claim 10, further comprising a replaceable plastic mesh insect screen which fits perfectly and securely into the second straight duct.

12. The centrifugal air suction fan unit defined in claim 4, further comprising an accessible waterproof manual electric switch which sends an “on” or “off” signal to the air fan's timing device.

13. The centrifugal air suction fan unit defined in claim 4, further comprising a waterproof pressure-sensitive electric switch which fits under the toilet seat and sends an “on” or “off” signal to the air fan's timing device according to the application or removal of the user's weight to and from the toilet seat.

14. The centrifugal air suction fan unit defined in claim 4, further comprising a motion-sensitive electric switch integrated into the electric fan's casing which sends an “on” or “off” signal to the air fan's timing device according to the approach or departure of the user.

15. The centrifugal air suction fan unit defined in claim 4, further comprising an integrated timing device connected to the air fan's electric motor which activates it upon receiving the “on” signal from the electric switch, and deactivates it 30 seconds after receiving the “off” signal.

16. The centrifugal air suction fan unit defined in claim 4, further comprising a toilet seat cover shaped in the vicinity of the hinges, so as not to obstruct the detection of the user by the motion (or heat) sensitive switch when the seat cover is in the vertical position.

17. The centrifugal air suction fan unit defined in claim 4, further comprising a first straight duct which incorporates on its inside wall, a down-pointing water nozzle, which connects on the outside to a water supply through a solenoid valve.

18. The centrifugal air suction fan unit defined in claim 17, further comprising an electric solenoid water valve integrated into the air fan assembly and controlled by its timing mechanism, with its inlet connecting through a standard flexible hose to the water supply tap under the water tank, and its outlet connecting to the water nozzle.

19. The centrifugal air suction fan unit defined in claim 17, further comprising a second straight duct connecting with the first straight duct in, with an integral external ring collar to limit penetration, and a rubber sleeve approximately 25 mm in width, fitting perfectly and firmly into the air exhaust opening in the toilet bowl, and reaching to within about 10 mm from the bottom of the auxiliary air duct, thus forming a water bottle trap system.

20. The centrifugal air suction fan unit defined in claim 18, further comprising an integrated timing device connected to the air fan's electric motor and to the solenoid valve, the timing device activates the air fan upon receiving the “on” signal from the electric switch, and deactivates it 30 seconds after receiving the “off” signal, the timing device then opens up the solenoid water valve for 5 seconds, and then closes it up.

21. The self ventilating toilet bowl as defined in claim 2, wherein a replaceable plastic plug with a rounded top and a 25 mm-long shank and a rubber sleeve is provided to fit perfectly and securely into the external circular openings.

22. The centrifugal air suction fan unit defined in claim 4, further comprising a heat sensitive electric switch integrated into the electric fan's casing which sends an “on” or “off” signal to the air fan's timing device according to the approach or departure of the user.

Description:

BACKGROUND OF THE INVENTION

1. Field of the Invention

The history of the art of ventilating foul air from toilet rooms goes back to the time when domestic and communal toilet facilities were first introduced. Venting of malodors directly from toilet bowls before they pervade in toilet rooms had been tackled in recent years by many in different ways and to different degrees of practicability, but with very limited commercial success.

2. Description of the Related Art

One common approach is whereby malodors are sucked by an electric fan directly from the toilet bowl through a flat intake nozzle placed between the toilet rim and the toilet seat, or through holes and a cavity incorporated into the toilet seat itself. The gases are re-circulated into the toilet room after passing through filters and deodorants, or alternatively are directly exhausted through a vent duct to the outside.

Practical testing of suction methods of malodor directly from toilet bowls by the inventor have confirmed that the single intake nozzle solution (even with a 24 VA electric fan) is sufficient to achieve the necessary venting of the toilet bowl without causing discomfort to the user, or allowing any of the malodor to spill out into the toilet room.

Suction through holes and a cavity in the toilet seat itself will also provide the necessary ventilation, but at a higher cost to the consumer. Such systems also incur technical difficulties at the toilet seat hinges with the suction and/or exhaust pipes which are normally addressed by the deployment of flexible piping, or hollowed hinges which double up as exhaust pipes. Since hinges are subject to continuous movement during use and cleaning, both such solutions can lead to early deterioration which will require maintenance or replacement of parts to avoid gas leaks. (Patents JP, 2004-209192; JP, 2005-163512; U.S. Pat. No. 6,772,449, U.S. Pat. No. 6,795,980, U.S. Pat. No. 7,103,925.)

The use of the single nozzle intake method is also strewn with shortcomings if attention to detail is not meticulously observed. If the nozzle is not fixed to the toilet assembly, the use of such a system will be limited to domestic toilets, and even there might still be subject to mishandling. (Patents JP, 2006-144519; U.S. Pat. No. 6,948,192; U.S. Pat. No. 6,550,072). If the intake nozzle is positioned below the toilet bowl rim level, the air pump might be damaged due to suction of contaminated water if the toilet bowl is clogged and it is flushed while the air pump is operating (Patents JP, 2006-152553; JP, 2003-096874; JP 2002-004382; U.S. Pat. No. 6,499,150). The said damage will be further aggravated due to flooding of the air fan if it is placed at a level below that of the toilet bowl rim.

Venting systems which use filtration and/or deodorizing of malodor and then re-circulating the treated gases into toilet rooms have been known to cause allergies and discomfort to many people. Such systems also rely in their operation on replaceable consumable parts, which require continuous financing and maintenance, and are an additional burden on the environment.

Systems whereby malodor is exhausted to the outside either through a special duct directed to a ceiling extraction fan, or through a special hole in the toilet wall or ceiling can be efficient from a functional point of view. However the installation of ventilation ducts inside tidy toilet rooms is considered an unsightly proposition which most people would decline. Ventilation ducts in some cases can be obstructive to the user or to the cleaner. Making special holes in toilet room walls and ceilings in addition to being aesthetically damaging to buildings, is generally not allowed in rented property or in apartment buildings.

Systems whereby malodor is vented directly from the toilet bowl and exhausted into the drainage system has been described by others, but none was found to cover the numerous and important details which, without being addressed meticulously, would place limitations on the practicability, function or reliability of such systems.

In Patents JP 2002-047715 and U.S. Pat. No. 7,103,925, the inventors have not addressed the conflict of the exhaust ventilation duct with the water duct connecting the water tank with the toilet bowl. Drilling a hole into the toilet bowl behind the toilet seat to a “spot above the water level in the inverted U-section of the trap” would pierce the flush water duct which supplies water to flush the toilet bowl, thus damaging the toilet bowl completely.

In patents JP 2003-096874 and U.S. Pat. No. 6,499,150, the intake nozzles and air fan units are positioned below the toilet bowl rim level, which will cause flooding of and damage to the electric air fans due to suction of contaminated water if the toilet is clogged and it is flushed while the air fan is operating. The air fan units are also placed behind the toilet bowl and under the water tank, which complicates accessibility for maintenance and replacement purposes.

SUMMARY OF THE INVENTION

The invention illustrated herein is an improvement to standard toilet bowls which provide the user with a self ventilating toilet bowl without the shortcomings of the aforementioned systems.

The invention comprises a system whereby fowl air is sucked directly from the toilet bowl before it contaminates the toilet room, and is discharged (via the toilet bowl itself) to the outside through the drain's vent which is normally installed at the highest point in the building.

The special feature comprises the integration into the toilet bowl of a dedicated auxiliary duct connecting an external circular opening in the toilet bowl's top behind the seat to one side (either left or right) of the flush water duct (causing no obstruction thereto) with another opening in the top side of the air chamber inside the toilet bowl behind and above the siphon. The subject auxiliary duct (and the two circular openings) will be included homogeneously with the toilet bowl during the manufacturing stage without the introduction of any foreign material to the product, or the requirement of any additional special equipment to the production line. A special removable plastic plug with a rounded top and a 25 mm-long shank of a colour blending with that of the toilet bowl is provided to fit securely into the external circular opening behind the toilet seat thus blocking it completely.

The toilet bowl can then be installed into any standard toilet room without requirement of special preparations or accessories or special expertise (apart from the provision of an electric socket close to the toilet bowl for power option from the mains).

If required by the owner, the special air fan can be retrofitted to the toilet bowl to convert it into a self ventilating toilet bowl.

The fan comprises a damp-proof, low-noise and low voltage (6-12V) electrically driven centrifugal (or other) air fan within a water-proof and sturdy casing of a suitable colour. The casing is pivoted at its rear centre to the vertical part of a sturdy L-shaped plate base which has a horizontal part that fits below the toilet seat and is fixed to the toilet bowl at the toilet seat's anchor holes. Air suction from the toilet bowl is secured through a flat-shaped replaceable (for cleaning) nozzle which reaches under the back of the toilet seat, but does not extend into the bowl or below the bowl's rim. Exhaust is provided through a pipe outlet which connects securely with the special external circular opening in the toilet bowl. A biased (in the closed position) one way flapper and a mesh insect screen are deployed inside the exhaust duct to prevent the ingress of malodor and insects from the drains when the system is dormant.

The air pump is actuated either manually: by a pressure-sensitive water proof switch located on the base plate under the toilet seat, or through an optical or heat sensor. The air pump is actuated upon the application of the user's weight (or approach) to the toilet seat.

The electric air fan causes a mild draft within the toilet bowl in the direction of the intake nozzle. Malodor is directed through the air fan, and out through the exhaust outlet. Upon the actuation of the electric fan, the one way flapper is pushed into the open position allowing the sucked malodor to go through the dedicated auxiliary duct in the toilet bowl, to be vented out through the drain's vent at the top of the building.

A timing device integrated into the electric air fan switches it off 30 seconds after receiving a signal from the operating switch that the user has finished use of the toilet bowl. The (biased) one-way flapper goes back to its normal closed position. Any backflow of gases from the drain will push the flapper further into the closed position thus stopping the ingress of foul gases into the toilet room.

In an alternative embodiment of the invention, the biased one way flapper and the mesh insect screen are replaced by the deployment of a secondary water “bottle” trap configuration in the auxiliary duct to prevent the ingress of malodor and insects from the drains when the system is dormant. Upon the actuation of the air fan, the water in the secondary water trap is pushed out by the exhaust gases into the drain, and the foul gases are vented out as explained above.

A water supply nozzle (pointing in a downward direction) is deployed inside the exhaust pipe. A flexible water pipe connects the water nozzle through a solenoid valve to the water supply tap under the water tank. The solenoid valve is controlled by the timing device inside the air fan assembly whereby it opens up for 5 seconds after the air fan stops, and then closes. Water thus supplied will replace the water in the “bottle” trap which was pushed out into the drain upon the actuation of the air fan.

The versatility, simplicity and homogeneous construction of both toilet bowl and air pump makes manufacturing and recycling economical and environmentally friendly. The system is totally fixed to the toilet assembly and is therefore suitable for installation in domestic and public toilets, and does not require any consumable material or special servicing. The installation of the system and the eventual replacement of the electric pump does not require any special training. There will be almost no mentionable additional cost in the manufacturing of the toilet bowl, and the electric air fan is simple, versatile and economical. The special features of the invention do not in any way impair or impede the function or the aesthetic looks of the other standard components of the toilet assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention described herein is best described in conjunction with the following attached drawings and illustrations:

FIG. 1 is a diagrammatic perspective view of the improved toilet bowl (with the external circular opening behind the toilet seat; the specially supplied plastic plug for blocking it if required, and the dedicated built-in auxiliary duct connecting it to the opening in the top side of the air chamber inside the toilet bowl behind and above the siphon).

FIG. 1A is a diagrammatic perspective side view of an alternative form of the design where access to the air chamber inside the toilet bowl behind and above the siphon is made directly through an external circular opening from the rear side of the toilet bowl. This alternative embodiment of the invention can be applied to toilet bowls where design considerations do not allow the installment of the exhaust opening behind the toilet seat.

FIG. 2 is a cross-sectional view of the improved toilet assembly illustrating the various elements which contribute to the self-ventilating quality of the invention, and explains the process through which malodor is vented out of the toilet bowl directly to the outside.

FIG. 3 is a top plan view of the improved toilet bowl illustrating its various elements.

FIG. 3A is a blown-up illustration of FIG. 2.

FIG. 3B is a cross-sectional view of the improved toilet bowl illustrating the built-in dedicated auxiliary ventilating openings and ducts in relation to the flush water duct and the air pocket behind and above the siphon.

FIG. 4 is a diagrammatic perspective view of the air fan assembly with the air intake nozzle in place.

FIG. 4A is a diagrammatic perspective view of the air fan with the intake air nozzle detached, exposing the inlet opening and the impeller protection grating.

FIG. 4B is a diagrammatic view of a detached air intake nozzle.

FIGS. 4C and 4D are diagrammatic views of the air fan assembly illustrating details of the attachment of the air fan casing to the base plate.

FIGS. 4E and 4F are diagrammatic views illustrating the two alternative settings of the air fan with the exhaust outlet pointing to the left or to the right (as required).

FIG. 5 is a cross-sectional view of the air fan assembly installed in place showing the various external elements and anchoring to the toilet bowl.

FIG. 5A is a cross sectional view of the air fan assembly showing the various elements of the exhaust air duct.

FIG. 6 is a cross-sectional view of the alternative embodiment of the design where a secondary water trap is deployed inside the auxiliary duct (acting as a bottle trap) to prevent the ingress of malodor and insects from the drains when the air pump is dormant.

DETAILED DESCRIPTION OF THE INVENTION

The invention illustrated herein discloses an improvement to standard toilet bowls whereby ventilation is effected directly from the toilet bowl itself without the requirement of any special preparations or installations inside the toilet room, or the use of consumable filters and deodorants.

With reference to FIG. 1, the apparatus consists of a toilet bowl 1 (pedestal or cantilever) made homogeneously of any suitable material (vitreous china, plastic, metal etc.) with seat anchor holes 16 and flush water inlet 15. A circular hole 9 in the toilet bowl behind the seat to one side (either left or right of the flush water duct); a dedicated auxiliary air duct 10 connecting opening 9 with another circular opening 8 in the top side of the air chamber inside the toilet bowl behind and above the siphon. All elements are homogeneously integrated into the toilet bowl during the manufacturing stage. Plug 17 is a removable plastic plug with a rounded top and a 25 mm-long shank of a colour blending in with that of the toilet, and a rubber sleeve 18. Plug 17 fits securely into opening 9 thus blocking it completely if the self ventilating feature of the toilet bowl is not required for any reason.

FIG. 1A is an alternative embodiment of the apparatus where both opening 9 and auxiliary air duct 10 are omitted, and opening 8 is factory-installed in the outer side of the toilet bowl thus connecting its outer side with its inside behind and above the siphon. Plug 17 with rubber sleeve 18 is intended to fit securely into opening 8 if the self ventilating feature of the toilet bowl is not required for any reason.

FIG. 2 is a cross-sectional view of the toilet assembly illustrating the self-ventilating process within the toilet bowl. With electric air fan 105 installed to toilet bowl 1 with its inlet nozzle 102 extending between toilet seat 2 and the bowl rim 1a (in the space formed by padded spacers 5), but not extending beyond or below the bowl's rim. An air draft in the direction of air intake nozzle 102 is created inside toilet bowl 1 upon actuating the air pump. Malodor is drawn into nozzle 102, through air fan 105, into opening 9 and duct 10, through opening 8 and into air pocket 20 behind and above siphon 3, through drain 6, and up to the top of the building into the open air through drain vent 7.

FIGS. 3, 3A and 3B are illustrations of the toilet bowl. The distance between water tank 4 and anchor holes 16/bowl rim 1a is to be sufficient to accommodate the installation of the electric air fan. Circular opening 9 and air duct 10 are located as such to avoid conflict with flush water duct 19, reach the top of air pocket 20 (behind siphon 3), and provide sufficient distance from water tank 4 for the installation of the electric air fan. Auxiliary air duct 10 extends 30 mm below the bottom of opening 8 to allow for the deployment of the (bottle) water trap alternative, if required.

FIGS. 4-4B are illustrations of the electric suction air fan 100. A low voltage (6-12V battery, or mains powered through a transformer) electrically driven centrifugal (or of other configuration) air fan contained within a robust and waterproof plastic (or metal) casing 105. The dimensions of casing 105 are to be as small as is sufficient to provide efficient low-noise suction of malodors from the toilet bowl, and to fit between toilet seat anchor holes 16 and water tank 4. Casing 105 is provided homogeneously with a circular inlet opening 108 near its front centre, and a discharge tube 107 at its upper tangent. A protection grating 109 is deployed at the inlet to protect the air fan impeller 114 from accidental damage. A detachable (for cleaning) hollow air intake nozzle 102, circular at the upper end to fit securely onto inlet opening 108, and flat at the lower end to fit between toilet seat 2 and toilet bowl rim 1a.

As illustrated in FIGS. 4C-F, casing 105 is fitted to the vertical part of an L-shaped robust base plate 104 at its rear centre. During assembly, an indented “tongue” 122 in the rear center of casing 105 is aligned into a perfectly matching “groove” 121 indentation in plate 104, with discharge tube 107 pointing either to the left or to the right (as required). Bolt 123 is then threaded into position through 120 and tightened into threaded hole 124 thus fixing casing 105 to base plate 104. Anchor holes 116 are provided in base plate 104 to overlap perfectly with the toilet bowl's seat anchor holes 16 for securing the assembled air fan to the toilet bowl.

As illustrated in FIGS. 4A, 4E and 4F, base plate 104 is shaped to allow extra depth (the thickness of the plate) to the intake nozzle opening thus providing better and quieter air suction from under the toilet seat.

The air fan is actuated either manually through a dedicated switch; by a pressure-sensitive water proof switch located on the base plate under the toilet seat, or through an optical or heat sensor 106 located on casing 105. Obstruction of sensor 106 shall be avoided by proper shaping (or removal) of the toilet seat cover. The air pump is actuated manually, or upon the application of the user's weight to the toilet seat (or his approach to sensor 106), and through a built-in timing device, switches off 30 seconds after receiving a signal from the operating switch that the user has moved away from the toilet bowl.

FIGS. 5 and 5A illustrate air suction fan 100 fitted in place on toilet bowl 1. Base plate 104 is placed on toilet rim 1a with anchor holes 116 aligned perfectly on top of anchor holes 16 on the toilet bowl, and under toilet seat 2. Anchor bolts 126 are then threaded through and tightened thus anchoring base plate 104 and toilet seat 2 to toilet bowl 1. Discharge tube 107 is fitted with elbow duct 108, duct 109, and duct 110, which is fitted with rubber sleeve 18 to fit perfectly and securely into opening 9 in the toilet bowl. Discharge tube 107 is fitted with a replaceable biased (in the closed position) one way flapper 112, which remains closed until pushed open upon actuating air fan 100. Duct 110 is fitted with an internal replaceable plastic mesh inset screen 113, and an external integral ring collar 115 to control penetration into opening 9.

FIG. 6 illustrates the alternative embodiment of the apparatus where a (bottle) water trap concept is deployed inside auxiliary air duct 10 to prevent the ingress of foul gases and insects from the drain when the air fan is dormant. Exhaust air pipe's bottom end 110a is immersed into a water trough at the bottom of auxiliary air duct 10. Upon actuating the air fan, exhausted foul gases push the water out of the secondary water trap, and through opening 8. The foul gases are then ventilated out as explained above. When the air fan is de-actuated (30 seconds after the user moves away from the toilet bowl), the timing device opens up a solenoid valve (for about 5 seconds only) which supplies water through nozzle 121 into exhaust pipes 109a, then 110a into the water (bottle) trap at the bottom of auxiliary air duct 10.

In the alternative embodiment of the invention as illustrated in diagram 1A, discharge duct 110 (with rubber sleeve 18) is placed securely into opening 8, and is connected by a (flexible or rigid) duct to an air fan which can be installed on the wall behind the toilet bowl above the toilet rim level. Malodor suction is effected through a special detachable nozzle which is fitted between the toilet seat rim 1a and toilet seat 2. This embodiment of the design can also be fitted with an external secondary water trap if required as an alternative method to prevent the ingress of foul gases and insects from the drainage system when the air fan is dormant.

The above illustrations and descriptions are not to be construed as limiting to the scope, spirit or details of the invention. Variations thereof, omissions therefrom or additions thereto can be made without departing from the spirit and scope of the invention.