GB2181168A

GB2181168A - Lavatory ventilator

Info

Publication number: GB2181168A
Application number: GB08623327A
Authority: GB
Inventors: Stephen Lloyd
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-10-02
Filing date: 1986-09-29
Publication date: 1987-04-15
Also published as: GB8623327D0

Abstract

A lavatory ventilation system comprises an extractor fan 22 coupled to the flushing water feed means 12 for the lavatory bowl 10, thereby extracting smells from the lavatory bowl (which is mainly where they originate) via the water flushing distribution channel 13 of the bowl 10. The fan outlet pipe 23 is thus of relatively small diameter. For a close- coupled cistern 11 and bowl 10 system, the ventilator pipe may alternatively be coupled to the bottom of the flushing mechanism and housing in the cistern, or to a suitably adapted washer which seals the end of the water feed pipe 12 to the entry to the bowl 10. The fan may be controlled by a simple on-off switch, or by any of a variety of automatic control systems controlled by sensors, e.g. of the seat position or of the light in the lavatory. <IMAGE>

Description

SPECIFICATION Lavatory ventilator The present invention relates to the ventilation of lavatories.

Some form of forced ventilation for lavatories is often very desirable, in view of the offensive smells which may occur in lavatories, and it is well known to provide such forced ventilation. A common arrangement is the provision of an electrically driven fan mounted on an outside wall with a vent to the outside, or mounted on a window.

Such a ventilation system has certain drawbacks. For example, a considerable airflow is required to change the volume of air in a typical lavatory in a short time, so the flow channel of the fan is therefore made of relatively large area. The pressure generated by the fan is, however, often relatively low, and wind pressure against the outside wall may then often seriously reduce the flow. These problems can be overcome by the use of a sufficiently high power fan, but that tends to cause more noise and costs more to install and run, and results in a considerable loss of warm air in winter.

It has been proposed to provide a ventilation system with a flattened inlet vent arranged adjacent to and just behind the hinge of the lavatory bowl seat and cover. This arrangement alleviates some of the above problems; in particular, the air is extracted from near the region where the smells normally originate. However, this system has its own disadvantages. For example, a special construction of lavatory seat and lid is required to accommodate the extractor inlet vent, which makes the provision of a choice of colours expensive, and the arrangement presents difficulties in cleaning the lavatory bowl, seat, and lid adequately.

The object of the present invention is to provide a lavatory ventilation system which alleviates or overcomes these problems.

Accordingly the present invention provides a lavatory ventilation system in which an extractor fan is coupled to the flushing water feed means for the lavatory bowl. The fan is preferably coupled to the water coupling pipe between the lavatory cistern and the lavatory bowl.

This arrangement has the advantage that the air is extracted from inside the lavatory bowl, which is where the offensive smells normally originate. by means which do not affect the appearance of the lavatory or adversely affect the ease with which it can be cleaned, and provides this advantage by means which are unobtrusive and involve no great mechanical complexity. Since the coupling pipe is of relatively small diameter, the fan is preferably designed for a higher air velocity and lower channel area than ordinary wall or window mounted extractor fans.

The fan may vent to an outside wall; alternatively, the fan may be incorporated in a deodourising unit which returns the de-odourised air to the lavatory.

The fan may be controlled by a simple onoff switch, but a variety of automatic control systems can be used for switching it on and off for a suitable period each time the lavatory is used.

Lavatory ventilating systems embodying the invention will now be described, by way of example, with reference to the drawings, in which: Figure 1 shows a lavatory cistern and bowl and ventilation means coupled thereto; Figure 2 shows a modified detail of the system; Figure 3 shows a further modification of the system; Figure 4 is an exploded partial section of a conventional close-coupled lavatory cistern and bowl; and Figure 4A shows a modified element of the Fig. 4 system.

Fig. 1 shows a lavatory bowl 10 and cistern 11 coupled together by a coupling pipe 12.

The cistern has a conventional overflow pipe 14. The bowl 10 has a flushing water distribution channel 13 formed around its inside rim, which the coupling pipe 12 feeds. A junction 20 is formed in the coupling pipe 12, and the branch 21 from this junction is connected to an extractor fan 22 with an outlet pipe 23 passing through the outside wall like the overflow pipe 14.

It is evident that when the fan is running, air is extracted from the interior of the lavatory bowl 10. This extraction is particularly efficient if the lavatory seat cover is down, or if the opening of the lavatory bowl is partially closed by a user.

The fan 22 may be operated by a conventional on-off switch. However, it may instead be operated automatically, to respond to a sensor sensing when the lavatory is used, such as a sensor which senses when the lid of the lavatory is lifted or, if the lavatory has no natural lighting, when the light in turned on. Such automatic operation preferably includes timing means for turning the fan off a fixed time after the sensor signal ends (i.e. the lid is closed or the light is turned off).

The fan may vent its output through an outside wall, as for an ordinary extractor fan.

This will often be very convenient, because lavatories are usually located close to an outside wall so that the overflow pipe can be arranged in the conventional manner. The outlet from the fan of the present system can conveniently be a pipe of the same diameter as the water pipe coupling the cistern and bowl, this diamter being much less than that for normal extractor fans, and a hole in the wall adjacent to the overflow pipe can there fore be made for the outlet pipe relatively easily.

It may be convenient to form this pipe with a slightly larger diameter and with two separate channels, one of which is used for the ventilation system and the other of which is used as the overflow pipe. However, it would be desirable to keep the two channels separate in the pipe, to avoid the dangers of overflow water getting into the fan and of back flow of air into the lavatory cistern.

As noted, the fan may, instead of venting to the ouside, feed a de-odouriser which deodourises the air and returns it to the lavatory.

Fig. 2 shows an elaboration of the system of Fig. 1. Provided that the pressure drop produced by the fan is not too great, the water flow during flushing should not produce any water flow into the fan, and a suitable choice of the vertical interval between the junction 20 and the inlet level at the fan 22 should ensure this. But if desired, a conventional water-stop valve 30 can be included in the pipe 21. The valve 30 is shown as including a ball 31 which will float on water, supported on fins 32 to leave a free passage for air, and a sealing seating 33 against which the ball 31 will press if water enters the valve 30 and causes the ball 31 to float up against the seating 33.

A simple plastic flap incorporated in the junction 20 may in fact be sufficient, the flap being pressed against the opening of the pipe 21 by the force of the water flowing from the cistern 11, but its resilience being sufficient to keep it open against the force of the air flow produced by the fan 22.

With certain lavatory bowl and cistern designs of the close-coupled type, it may not be easy to get at the coupling pipe 12 between the cistern 11 and the bowl 10. Fig 3 therefore shows a modification of the system for such a design. The cistern 11 contains the flushing mechanism and housing 40, which includes the syphon bend 41 and is integral with the coupling pipe 12. The junction 20 is shown as formed in the housing 40, near where it becomes the pipe 12 as it passes through the bottom of the cistern. The junction 20 is extended in the form of a rising pipe 42, with a coupling 43 at its upper end.

The fan 22 will be connected to this coupling 43 by a pipe (not shown) which will pass either through a surplus aperture in the cistern 11 (cisterns often being provided with several apertures, to allow the feed and overflow pipes to be connected on either side, with the unused apertures normally being sealed off), or via a cut-out in the upper rear edge of the body of the cistern 11.

This arrangement has the disadvantage that the provision of the pipe 42 may interfere with the efficiency of the syphon action, or the water level at which it ceases, or both. To alleviate these dangers, the junction 20 should be formed as low as possible on the housing 40. In addition, a one-way air valve (not shown) may be provided in the pipe 42, preferably near its lower end, to minimize the effect of this pipe on the syphon and flushing action. This valve may be constructed like the valve of Fig. 2 but without the fins 32 and with a sealing seating on which the ball normally rests, so that the ball seals against the flow of air from the pipe 42 into the housing 40 and the pipe 12. Of course, this valve may also serve to prevent the flow of water up the pipe 42, in the same way as the valve of Fig.

2.

A different arrangement for use with a lavatory cistern and bowl of the close-coupled type is shown in Figs. 4 and 4A. Referring to Fig. 4, a flange 46 forms the boundary between the water channel pipe portions 12 (below the cistern 11) and 44 (which forms part of the flushing mechanism and housing 40).

The portion 12 is threaded as shown at 45.

A firm rubber washer 50 seats between the flange 46 and the bottom of the cistern 11 to provide a watertight seal. The pipe 12 passes through an oval metal plate 51 which seats against the underside of the cistern 11, the plate 51 having its ends bent down slightly as shown and provided with slots (not shown).

A firm rubber washer 52 seats against the plate 51, and a hard plastic hexagonal nut 53 with a flange 54 is screwed up the pipe 12 to grip the washer 50 firmly between the flange 46 and the inside of the base of the cistern 11, and to grip the washer 52 and the plate 51 firmly between its flange 54 and the outside of the base of the cistern 11.

A washer 60 of soft and compressible material fits over the nut 53, seating against the flange 54. The bottom end of the pipe 12 projects into the entry 13A of the flushing water distribution channel 13 of the lavatory bowl 10, which has a thinned portion 55 at its rear. Bolts 56 are placed with their heads held by the slots (not shown) at the ends of the plate 51, and the cistern 11 is held firmly on the bowl 10 by these bolts passing through holes 57 in the thinned portion 55 of the blow 10 and nuts 58 being screwed to these bolts; the washer 60 is compressed to form a seal between the nut 53 and the flushing water entry 13A.

Fig. 4A shows a modified form of the washer 60 which is formed as the end of the pipe 21 to allow air to be extracted from the entry 13A. In this form, the washer has an upper layer 61 and a lower layer 62 (of enlarged inner diameter) of the conventional soft and compressible material, but sandwiched between them is a layer 63 of hard plastics material which consists essentially of upper and lower plates and an outer cylindrical skin, giving a circulat interior space which communicates below with the entry 1 3A and at the side with the pipe 21, which is sealed to an aperture in the outer cylindrical skin. Inner strengthening ribs of pillars (not shown) can of course be provided. The outlet pipe 21 can be led out to the side of or behind the cistern 11. In this arrangement, the washer is 60 concealed between the bowl 10 and the cistern 11 in exactly the same way as washer 60 in the conventional construction of Fig. 4.

A further alternative is that a coupling hole may be drilled or otherwise formed at the back of the lavatory bowl for connection to the fan, communicating directly with the distribution channel 13 of the bowl.

The fan may of course be boxed in, or it may be located on the other side of the wall on which the lavatory cistern is mounted. In the latter case, the pipe 21 may be taken directly backwards through the wall behind the lavatory bowl, instead of being taken sideways as shown in Fig. 1.

Claims

1. A lavatory ventilation system in which an extractor fan is coupled to the flushing water feed means for the lavatory bowl.

2. A lavatory ventilation system according to claim 1 wherein the fan is coupled to the water coupling pipe between the lavatory cistern and the lavatory bowl.

3. A lavatory ventilation system according to claim 1 wherein the fan is coupled to the flushing mechanism and housing in the cistern.

4. A lavatory ventilation system according to claim 1 wherein the fan is coupled to a washer placed between the end of the water coupling pipe and the lavatory bowl to which it is coupled.

5. A lavatory ventilation system according to any previous claim wherein the flushing water feed means is coupled to the extractor fan via a valve.

6. A lavatory ventilation system according to claim 5 wherein the valve prevents water from passing towards the extractor fan.

7. A lavatory ventilation system according to either of claims 4 and 5 wherein the valve prevents air from passing towards the flushing water feed means.

8. A lavatory ventilation system according to any previous claim wheren the fan is coupled to or is incorporated in a de-odourising unit which returns the de-odourised air to the lavatory.

9. A lavatory ventilation system according to any previous claim wherein the fan is controlled by a simple on-off switch.

10. A lavatory ventilation system according to any one of claims 1 to 9 wherein the fan is controlled by an automatic control system.

11. A lavatory ventilation system substantially as herein described and illustrated.

11. A lavatory ventilation system according to claim 10 wherein the control system includes timing means.

12. A lavatory ventilation system according to either of claims 10 and 11 wherein the control system includes a sensor responsive to the position of the lavatory seat and/or lid.

12. A lavatory ventilation system according to either of claims 10 and 11 wherein the control system includes a sensor responsive to whether the light in the lavatory is on or off.