GB2346159A

GB2346159A - Regulating amount of discharge from siphon-discharge flushing cistern

Info

Publication number: GB2346159A
Application number: GB9822990A
Authority: GB
Inventors: John Henry May
Original assignee: FLUID CONTROLS U K Ltd
Current assignee: FLUID CONTROLS U K Ltd
Priority date: 1998-10-22
Filing date: 1998-10-22
Publication date: 2000-08-02
Also published as: GB9822990D0

Abstract

A device for controlling the volume of water discharge from a toilet cistern comprises an upper chamber 1 which is rigidly connected to a lower chamber 2. The lower chamber is rigidly attached to a weighted base 3. In the lower chamber a cylindrical tube 4 is rigidly fixed to the base. Within this tube a shaft 5 is rigidly attached to a disc 6 which in turn is rigidly attached to the upper chamber 1 and provides a guide path enabling free vertical movement of the upper chamber and ensures that the upper chamber and float assembly 8 & 9 remain in a vertical position irrespective of the level of water in the cistern. The walls of the lower chamber 2 are in part built with a complete cylindrical section of flexible material 7 enabling a free vertical movement of the upper chamber. The position at which the device is set when the cistern is full is set by the rigid connection between the float 8 and the length of the shaft 9 rigidly connected to the disc 6. In the lower chamber preferably two small apertures and or aperture(s) in the disc 10 or a multiplicity thereof are so arranged to enable the free movement of water between the upper chamber 1 and water contained in the cistern. These may be placed at any boundary of the lower chamber in contact with the water in the cistern. At the base of the upper chamber or any other convenient position of the upper chamber provision is made for a flexible tube or pipe 11 to be connected so enabling the free passage of water or air between the upper chamber and a fitting or sealed hole 12 on which can be positioned at any point on the syphon so that the influx of air de-primes the syphon.

Description

DESCRIPTION TOILET FLUSH VOLUME CONTROLLER This invention relates to a mechanism which can be added to any existing toilet cistern syphon or included in the rianufacture of toilet syphons to control the volume of water discharged from a toilet cistern. The invention is described through the operation of a commonly used portsmouth style ball valve, however, its uses are not so limited and it can be applied to any toilet system whatever the filling mechanism.

The water used for a toilet is a major component of household usage of water, typically representing one third on housçhold use. Volumes used for flushing are unnecessarily greater than previously considered and in periods of water shortages if the unnecessary waste caused by the additional flush volumes were to be eliminated this could avert th difficulties encountered by water undertakings and their customers. The ptoblem of additional flush volumes is described below ; The volume of water used to flush a toilet comprises of the water stored in the cistern and a proportion of the water entering through the ball valve whilst the syphon is primed. This additional proportion of water is dependent upon the duration of the flush which in turn is a function of the discharge characteristics of the syphon, the initial volume of water stored in the cistern, the water pressure at the inlet of the ball valve and the discharge characteristics of the ball valve nozzle. A well known problem of ball valves is that with age and use, typically within 18 months the washer deteriorates and that the force required to completely close the ball valve increases. The closure force acting on the washer is de'vend from a lever arm connected to a partially submerged float. With a new washer the float is generally 20% submerged when the ball valve completely closes but with a worn washer the float is submerged by 50% or more before the ball valve closes. Hence since the closing force acting against the washer increases as the washer deteriorates, the float is more submerged and there is a greater volume of water is stored in the toilet cistern. This results in an increase in flush volumes. Typically the difference in the volume of water stored in the cistern before the toilet is flushed, between a net washer, 20% submergence of the float at closure of the valve, and a worn washer, 50% submergence of the float at closure of the valve is 2 Litres. Hence for a cistern with a new washer where the stored volume discharged is typically 8 litres for the same cistern with a wom washer the stored volume discharged is typically 10 litres. The problem of additional flush volumes is compounded by the fact that the duration of the flush increases for toilets with worn washers due to a greater volume of water stored in the cistern at commencement of the flush. Typically this adds a further one litre of water to the flush making a total flush volume of 11 litres.

Given that the majority of washers in operation are older than 18 months and that on average each person uses a toilet 7 times each day then at a minimum the additional volumes of water unnecessarily used to flush toilets is in the order of 21 litres of water per head per day. Which for an average occupancy of 2.5 people per property is over 50 litres per property per day It is therefore desirous to control flush volumes. This invention enables constant flush volumes to be delivered irrespective of the age of the washer and volume of water stored in the cistern. In addition to this the invention also enables the flush volumes to be varied by a simple adjustment, this too is desirous as the flush volume can be set according to the nature of the waste to be disposed of.

Accordingly the invention provides a means of modifying any existing or new toilet syphon so enabling the duration flush to be set by controlling the moment at which the syphon de-primes after flushing and ensuring flush volumes are independent of any increase in the level of water in the cistern above that in the case of the level with a new washer and also enabling the volume of the flush to be altered to a pre-set volume by means of a simple mechanical adjustment.

The invention is further illustrated by way of example only with reference to the accompanying drawings in which; Figure 1 is a longitudinal sectional through the device.

Figure 2 is a longitudinal sectional through a toilet cistern of the present invention prior to flushing where the ball valve is fitted with a new washer.

Figure 3 is a longitudinal sectional through a toilet cistern of the present invention prior to flushing where the ball valve is fitted with an old washer.

Figures 4 through to 8 are longitudinal sectionals through a toilet cistern of the present invention revealing the sequence of events from flushing to depriming of the syphon.

Figure 9 is an example of the present invention wherein an adjustable collar is placed to alter flush volumes.

The device Figure 1 comprises of an upper chamber 1 which is rigidly connected to a lower chamber 2. The lower chamber is rigidly attached to a base 3 the weight of which is significantly greater than the buoyancy forces generated by the displacement of water of the wetted parts of the device so that it is not easily disturbed by the movement of water within the cistern. The base 3 may be of the form of a sealed sand filled plastic container. In the lower chamber a cylindrical tube 4 is rigidly fixed to the base and within this tube a shaft 5 rigidly attached to a disc 6 which in turn is rigidly attached to the upper chamber 1 provides a guide path enabling free vertical movement of the upper chamber and ensures that the upper chamber and float assembly 8 & 9 remain in a vertical position irrespective of the level of water in the cistern. The walls of the lower are in part built with a complete cylindrical section of flexible material 7 enabling a free vertical movement of the upper chamber. The position at which devices is set when the cistern is full is set by the rigid connection between the float 8 and the length of the shaft 9 rigidly connected to the disc 6. In the lower chamber preferably two small apertures and or aperture (s) in the disc 10 or a multiplicity thereof are so arranged to enable the free movement of water between the upper chamber 1 and water contained in the cistern. These may be placed at any boundary of the lower chamber in contact with the water in the cistern. At the base of the upper chamber or any other convenient position of the upper chamber provision is made for a flexible tube or pipe 11 to be connected so enabling the free passage of water or air between the upper chamber and a fitting or sealed hole 12 on which can be positioned at any point on the syphon so that the influx of air de-primes the syphon.

Figure 2 shows the level of water in a cistern which is fitted with new washer in the ball valve and Figure 3 shows the level of water in a cistern fitted with an old washer in the ball valve washer.

In Figures 2 and 3 it be appreciated that the distances marked x between the water level in the cistern and the rim of the upper chamber 1 is identical and that the lower chamber is extended in figure 3. This is enabled by the buoyancy forces generated by the float 8 which is accommodated by the flexible walls of the lower chamber and that water can move into and out of the lower chamber through the small apertures. It will be appreciated that the rise in the level of water in the cistern as a function of the age and use of the ball valve washer is a gradual process taking months or years, however, through the duration of a flush typically in the order of 8 seconds the amount of water lost from the chamber is negligible and that the height of the upper chamber is virtually unchanged. This being a result of the small apertures between the boundary of the lower chamber and the remainder of the cistern.

In Figure 4 as the syphon is primed by raising the plunger 13, water is also initially forced from the syphon into the upper chamber 1.

In Figure 5 with the syphon primed water in the upper chamber is drawn by suction forces into the syphon.

In Figure 6 when the upper chamber 1 is empty air is drawn into the syphon and in Figure 7 the syphon becomes de-primed as a result of the air drawn through the upper chamber and the plunger returns to its start position.

In Figure 8 the action of the toilet returns to normal and water enters int the cistern the level rising until the ball valve closes as in Figures 1 and 2.

It will be appreciated that since the level between the surface of the water in Figures 1 and 2 is the same then the volume of water discharged in either example is substantially the same and that during the brief period of the flush the passage of water from the lower chamber by the action of the small exposed weight of the shaft 9 and the float 8 is restricted by the small apertures in the lower chamber 2 the vertical position of the lower chamber 2 and therefore upper chamber 1 remains essentially unchanged. However, between flushes there is more than sufficient time to enable the position of the lower chamber to adjust to any change in the level of water in the cistern.

This being a particular benefit in that as the ball valve washer deteriorates the flush volume remains constant, which in the absence of this invention cannot occur.

It will also be appreciated that since part of the flow used to prime the syphon is discharged back into the cistern Figure 4 this marginally reduces the total . volume discharged.

It will be further appreciated that the duration of the flush is also diminished due to secondary flow path afforded by the connection 12 into the syphon Figure 5. Thus the additional volume of water discharged due to the in-fill water being combined to the original flush volume is also reduced.

In order to alter the flush volumes a wide variety of means are possible. An example of one such arrangement is shown in Figure 9 here an adjustable collar 14 is so caused to move either up to reduce flush volumes or down to increase flush volumes. An alternative arrangement could be to alter the position of the float 8 in respect of the rim of the upper chamber.

It will also be appreciated that the means of adjustment of either of the above options could be effected as a simple switch or infinitely adjustable knob on the outside of the cistern so that the user can pre-select the flush volume.

The manner by which the flush volume can be altered may be undertaken through mechanical, hydraulic, magnetic or electronic means and the options for calibrated displays to presented as notches, diagrams or digital displays are yet further embodiments.

Claims

Claims 1. A means to control the volume of water discharged from a toilet cistem provided by a float which does not immediately react to the instantaneous fall in the level of water as the toilet is flushed and a tube suspended from the float which is connected to the syphon the position of the aforesaid tube remaining at a fixed position below the initial level of water in the cistern such that as the level of water descends to the point of entry into the tube air is conducted through tube to the syphon so causing the syphon to de-prime and controlling the flush volume following which water entering into the cistern gradually fills a flexible chamber beneath the float and so. enables the float to return to the top water level of the cistern on closure of the ball valve.
2. A means of altering the position of the tube below the float to enable adjustment of the volume of water discharged from the toilet.
3. Apparatus which controls the volume of water discharged from the toilet cistern as a function of the initial water level in the cistern.
4. Apparatus which controls the volume of water discharged from the toilet as a function of time.