GB2334042A

GB2334042A - Ventilated water closet

Info

Publication number: GB2334042A
Application number: GB9802377A
Authority: GB
Inventors: John Ernest Frederick Corfield
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-02-05
Filing date: 1998-02-05
Publication date: 1999-08-11
Also published as: GB9802377D0

Abstract

A water closet including a cistern (6) containing a siphon having an outlet communication with a lavatory pan (1) is ventilated by an air extraction pipe (11) communicating with the siphon outlet and air extraction means (15) situated outside the cistern and communicating directly with the air extraction pipe.

Description

VENTILATED SANITARY WARE FOR A WATER CLOSET This invention relates generally to the ventilation of a water closet, and in particular to improved ventilated sanitary ware for a water closet.

Building regulations require water closets to have adequate ventilation, preferably direct to the outside.

In circumstances where it is absolutely impossible for direct ventilation to the outside it is allowable to have forced ventilation by means of a fan and a duct leading to the outside. Typically the fan is linked to a light switch so as to be energised at all times that the water closet is occupied. This works to some extent in removing air contaminated with unpleasant odours from the room, but this can only be a partial solution in that what is really required is some means for preventing the odours from diffusing into the room in the first place.

The present invention is concerned therefore with extracting odours, created when the water closet is used, directly from the water closet sanitary ware itself.

Attempts to achieve this effect have been made in the past, but without success. Two common methods involve modifying either the lavatory pan seat or the lavatory pan itself in order to provide extraction airways. This involves replacement of the sanitary ware since such devices cannot be retrofitted. The present invention seeks to make use of the conduit through which flushing water reaches the pan to provide a ready made initial part of an odour extraction route.

As is well known, apart from the so-called "victoria" valves which act by timed self-closing action, flushing water normally reaches a water closet pan from a cistern in a typical arrangement by the action of a siphon. The outlet leg (hereinafter also referred to as the flushing pipe) of such a siphon is open to the atmosphere where it exits into the pan and is effectively sealed at its other end by the water in the water closet cistern. Therefore if the air in the flushing pipe were to be extracted from a point anywhere along its length other than where it exits into the pan replacement air would have to flow into the flushing pipe from the pan itself.

However, the result of joining an extracting airway to the flushing pipe is that the extracting airway will allow air (atmospheric air) to flow into the pipe at this point, which may be disadvantageous. The pressure of water (or siphon head) which drives the flushing effect is related directly to the distance between the top of the water in the inverted loop of the siphon pipe and the point at which the flushing pipe is open to the atmospheric pressure. Thus the siphonic effect is reduced by the action of joining an airway to the flushing pipe as just described.

One approach to this problem, utilising a one-way valve is shown in GB 2,182,368. However, there are a number of practical difficulties with such an arrangement. If the one-way valve allows air to leak into the outlet leg of the siphon, then the siphon action is destroyed. Also, the bias towards closure of the valve has to be sufficient to prevent water escaping into the overflow pipe during the flushing operation, yet also to be small enough to be overcome by the suction effect of an extraction fan at the end of the foul air extraction passage. This is difficult to achieve. Furthermore, in order to ensure that the one-way valve is shut when the water closet is flushed, some switch connection must be made between the power supply to the extractor fan and the water closet flush operating. Thus, in practice the system disclosed in GB 2,182,368 is cumbersome, with a number of points at which failure can occur. GB 2,209,356 shows another attempt at solving the problem of extracting foul air from a lavatory pan. In the arrangements shown, a connection is made between the siphon outlet tube at the point at which it leaves the cistern and an extraction fan which is situated inside the cistern but above the level of an overflow pipe. The extraction fan exhausts through a second pipe through the wall of the cistern. The extraction fan exhaust pipe includes a T-piece to which a dip tube is also attached.

Thus the extraction fan exhaust pipe also acts as an overflow pipe. However, the proximity of the junction between the extraction fan exhaust pipe and the dip tube to the exhaust fan means that if the ball-cock should fail, as they often do, water could enter the exhaust fan chamber. Also the leads to the extraction fan could become submerged. This, clearly, is undesirable.

In addition, as the extraction fan will be running during a flushing operation, there will be a tendency for water to be sucked up the inlet pipe to the extraction fan chamber. Again, this is an entirely undesirable state of affairs.

The present invention seeks to provide an improved water closet air extraction system, particularly intended for short term operations to extract foul air quickly from a region in and around lavatory bowls in order to prevent it from diffusing into the room.

According to the present invention there is provided sanitary ware for a water closet including a cistern containing a siphon having an outlet leg communicating with a lavatory pan, an air extraction pipe communicating with the siphon outlet leg and an air extraction means, wherein the air extraction means is situated outside the cistern and the air extraction pipe communicates directly with the air extraction means.

The word 'directly' is used to indicate that there are no valves or other obstructions in the air extraction pipe between the position at which it joins the siphon outlet leg and the air extraction means. In a preferred embodiment the air extraction means comprise a fan although it may take other forms.

Preferably the air extraction pipe forms part of the cistern overflow discharge pipe and the air extraction pipe includes a region which is higher than the overflow discharge point.

The present invention also comprehends sanitary ware for a water closet, of type comprising a lavatory pan and a cistern with a flushing water delivery pipe linking them, siphon means for introducing flushing water from the cistern into the flushing water delivery pipe, and an overflow discharge pipe defining a level in the cistern above which water overflows through the overflow pipe, in which there is provided an air extraction route for air from the lavatory pan through a part of the flushing pipe including a duct putting the flushing pipe into communication with the overflow pipe the latter including means for closing from the atmosphere the entrance by which water from the cistern enters the overflow pipe.

The closure means may be a tube the entrance end of which is below the surface of the water in the cistern when filled to a normal level. This ensures that the air extraction route is complete and includes no "leaks" to the room atmosphere through which escapes gas.

Preferably the entrance to the air extraction pipe is as low as is practicable in relation to the cistern.

Various embodiments of the invention will now be described, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a diagrammatic cross-section schematically illustrating a water closet embodying the invention; Figure 2 is a diagrammatic cross-section schematically illustrating a second form of water closet embodying the invention; Figure 3 is a diagrammatic cross-section schematically illustrating a third form of water closet embodying the invention; Figure 4 is a diagrammatic cross-section schematically illustrating a fourth form of water closet embodying the invention; Figure 5 is a diagrammatic cross-section schematically illustrating a fifth form of water closet embodying the invention; Figure 6 is a diagrammatic cross-section schematically illustrating a sixth form of water closet embodying the invention; Figure 7 is a diagrammatic cross-section schematically illustrating a seventh form of water closet embodying the invention; Figure 8 is a diagrammatic cross-section schematically illustrating an eighth form of water closet embodying the invention; Figure 9 is a diagrammatic cross-section schematically illustrating a ninth water closet embodying the invention; and Figure 10 is a diagrammatic cross-section schematically illustrating a tenth form of water closet embodying the invention.

Referring to Figure 1, a water closet embodying the invention includes a pan 1 which has a seat 2 which is raised above the upper rim 3 of the pan 1 by a number of pads 4. Thus, even when a person is seated on the pan 1, air from the room within which the water closet is contained can pass into the pan 1 of the water closet.

Flushing water 5 is stored in a cistern 6 from which it flows under siphonic action via a siphon 7 and flushing pipe 8 into the water closet pan 1. The siphon 7 has an inlet leg 9 and an outlet leg 10. A foul air extraction airway 11 is connected and sealed to the siphon outlet leg 10, and joins with a conventional overflow pipe 12 which passes through a wall 13 of the room in which the water closet is situated. The overflow pipe 12 includes a dip tube 14 the open end of which is below the level of the flushing water 5. A foul air extraction fan and housing 15 are attached to the end of the overflow pipe 12. The path from the end of the dip pipe 14 to the siphon outlet leg 10 includes a portion which is higher than any part of the portion of the overflow pipe 12 from the junction with the dip pipe 14 to the termination of the overflow pipe 12 so that in the event of a failure of a ball-cock water valve (not shown) which controls the flow of the flushing water 5 to the cistern 6 the excess water flows away from the flushing pipe. It is important that the design of the housing is such that water flowing along the pipe 12 in such circumstances is directed to the exterior without flowing through electrical parts of the fan 15.

In the arrangement shown in Figure 1, the foul air extraction fan and housing 15 are outside the room in which the water closet is situated. This has the advantage that no power supply for the foul air extraction fan has to be provided within the room in which the water closet is situated. It is also possible for the fan to be rotated by outside air movements or the connection currents between a warmer interior and a cooler exterior.

However, the foul air extraction fan can be positioned at any convenient position in the overflow pipe 12 between the wall of the cistern 6 and the termination of the overflow pipe 12. In either case, the arrangement of the housing 15 of the foul air extraction fan is such that, in the event of an overflow arising, the water in the overflow pipe 12 does not come into contact with the electrical parts of the foul air extraction fan.

Figure 2 shows a second embodiment of the invention in which the foul air extraction airway 11 is outside the cistern 6 and connects with the flushing pipe 8 of the water closet below the cistern 6. Those components which are the same as for the Figure 1 embodiment have the same reference numerals.

The point at which the foul air extraction airway 11 opens into the outlet leg 10 of the siphon 7 or the flushing pipe 8 effects the siphonic head available for a flushing and preferably should be as low as possible.

Figures 3 and 4 show two possible arrangements. In Figure 3 the foul air extraction airway 11 is with the cistern 6, as in Figure 1 embodiment of the invention. In Figure 4, the foul air extraction airway 11 is outside the cistern 6, as in the Figure 2 embodiment of the invention. Again, and for the other embodiments of the invention to be described, components which are the same as for the Figure 1 embodiment of the invention have the same reference numerals. In some water closet arrangements, for example for use in apartment buildings, an open-ended overflow pipe cannot be used and arrangements are made for the overflow pipe to discharge into the pan of the water closet. Figures 5 and 6 show water closets in which the overflow pipe is arranged to operate in this way. It will be noted that, in practice, the overflow pipe 12 is constituted by that part of the foul air extractor airway 11 which opens into the flushing pipe 8 of the respective water closet.

Figure 7 shows an arrangement in which the foul air extraction airway 11 and overflow pipe 12 pass through the cistern 6 and out through the bottom of it.

Figure 8 shows an arrangement in which the foul air extraction airway 11 passes outside the cistern 6 before joining the overflow pipe 12, which passes out through the bottom of the cistern 6, as for the previous embodiment of the invention.

Figure 9 shows an arrangement in which the foul air extraction airway 11 passes through the bottom of the cistern 6, but the overflow pipe 12 discharges into the outlet leg 10 of the siphon 7 within the cistern 6.

Figure 10 shows an arrangement in which the foul air extraction airway 11 again passes out through the bottom of the cistern 6 and the overflow pipe 12 passes out through the top of the wall of the cistern 6 to discharge into the flushing pipe 8 beneath the cistern.

In all the above embodiments of the invention, the foul air extraction airway 11 is completely free of any valves which might fail and affect the efficiency of its operation.

Claims

CLAIMS 1. Sanitary ware for a water closet including a cistern containing a siphon having an outlet communicating with a lavatory pan, an air extraction pipe communicating with the siphon outlet and air extraction means, in which the air extraction means is situated outside the cistern and the air extraction pipe communicates directly with the air extraction means.
2. Sanitary ware as claimed in Claim 1, in which the air extraction means comprise a fan.
3. Sanitary ware according to Claim 1 or Claim 2, in which the air extraction pipe forms part of the cistern overflow discharge pipe and the air extraction pipe includes a region which is higher than the overflow discharge point.
4. Sanitary ware for a water closet, of the type comprising a lavatory pan and a cistern with a flushing water delivery pipe linking them, siphon means for introducing flushing water from the cistern into the flushing water delivery pipe, and an overflow discharge pipe defining a level in the cistern above which water overflows through the overflow pipe, in which there is provided an air extraction route for air from the lavatory pan through a part of the flushing pipe including a duct putting the flushing pipe into communication with the overflow pipe, the latter including means for closing from the atmosphere the entrance by which water from the cistern enters the overflow pipe.
5. Sanitary ware as claimed in any preceding claim, in which the closure means is a tube the entrance end of which is below the surface of the water in the cistern when filled to a normal level.
6. Sanitary ware substantially as hereinbefore described with reference to, and as shown, in the accompanying drawings.