GB2298878A

GB2298878A - Dispensing unit for a toilet cistern

Info

Publication number: GB2298878A
Application number: GB9505097A
Authority: GB
Inventors: Roger Pitman
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-03-14
Filing date: 1995-03-14
Publication date: 1996-09-18
Also published as: GB9505097D0

Abstract

A dispensing unit 11 for a cistern subject to periodic flushing includes: an outlet from the unit through which material to be dispensed is supplied; a reservoir 12 of material to be dispensed in discrete doses; and a dispensing shuttle 20 which acts to dispense a predetermined measure of material from the reservoir to the outlet each time a flushing action occurs. Typically the dispensing shuttle contains a chamber 23 corresponding in volume to the predetermined measure and is displaceable between a first position wherein it is in communication with the reservoir and isolated from the outlet, and a second position where the chamber is isolated from the reservoir and communicates with the outlet. Preferably the shuttle is connected to a container which has been filled, in whole or in part, by water supplied from the cistern but is not immersed in water in the cistern acts to draw the shuttle from the first to the second position to enable material in the chamber to flow into the container; the container containing a bleed means whereby liquid in the container can pass out of the container into the cistern.

Description

DISPENSING UNIT This invention relates to a dispensing unit. In particular it is concerned with a dispensing unit which dispenses a measure of fluid on demand.

It is a common practice for flush toilets to be provided with a scenting, colouring, deoderising, de-scaling, or antiseptic material or a material providing a combination of some or all of these functions. There are three common methods for adding such a material to a toilet.

Firstly direct application from a container by hand. This requires the user to select and prepare the container and then to dispense the material. This method while simple does have problems. The amount of material dispensed can vary. Such material can have toxic or other adverse properties so making them unsuitable for use by children. It is difficuit to ensure that each user is clearly made aware of the need to use the material.

Secondly the material can be placed in the toilet cistern in the form of a soluble block. While this avoids the need for decisions as to whether to dispense and if so by what amount. However if the toilet is flushed frequently enough material may not have dissolved for an effective concentration of the dissolved material to have been reached in the standing water. Conversely if long periods occur between each flushing operation then the concentration of the dissolved material becomes excessive. As the block decreases in size its surface area decreases so reducing the rate at which the block can dissolve to achieve a given concentration in the standing water.

Thirdly rather than place the soluble block of material in a cistern it can be located in the toilet pedestal. This is unhygienic since the block and its mounting means can be contaminated directly. The block and its mounting serve to screen a part of the pedestal from the action of flushing water so leaving a polluted area. Again as the block decreases in surface area the rate at which the block can dissolve to dispense material falls reducing its effectiveness.

According to the present invention there is provided a dispensing unit for a cistern subject to periodic flushing including: an outlet from the unit through which material to be dispensed from the unit is supplied; a reservoir of material to be dispensed in discrete doses; and a dispensing shuttle which acts to dispense a predetermined measure of material from the reservoir to the outlet each time a flushing action occurs According to a first preferred version of the present invention the dispensing shuttle contains a chamber corresponding in volume to the predetermined measure and is displaceable between a first position wherein it is in communication with the reservoir and isolated from the outlet, and a second position where the chamber is isolated from the reservoir and communicates with the outlet.

Typically the shuttle is connected to a container which having been filled, in whole or in part, by water supplied from the cistern (but while not immersed in water in the cistern) acts to draw the shuttle from the first to the second position to enable material in the chamber to flow into the container; the container containing a bleed means whereby liquid in the container can pass out of the container into the cistern.

Again typically the dispensing unit includes a resilient biassing means acting on the shuttle so that with the container substantially empty the biasing means acts to restore the shuttle from the second position to the first and to maintain it in the first position.

An exemplary embodiment of the present invention will now be described with reference to the accompanying drawings of a dispensing device of which: Figure 1 is a perspective view from above; Figure 2 is a sectioned elevation of the device of Figure 1 on section II-II Figures 3 to 5 show a section of a toilet cistern incorporating the dispensing device with the components in various relative positions.

Figure 1 and 2 These variously show a dispenser 11 made up of a reservoir 12 with a hook or clip 13 to provide for the dispenser 11 to be located within a cistern. The reservoir 12 is provided with a neck 14 having an external screw thread 15 on which is mounted a valve unit 16. The reservoir is readily charged with working fluid which is to be mixed with water for flushing a toilet pedestal. The unit 16 comprises a cap 17 with an internal thread 18 whereby the unit is retained on neck 14 through interaction with thread 15. The cap 17 has a central boss 19 through which extend a double acting valve shuttle 20 with a lower frusto conical valve face 21 and an upper valve face 22. The shuttle 20 contains a chamber 23.The shuttle 20 has a top washer 24 acted on by compression spring 25 which, as shown in Figure 2, tends to bias the valve shuttle 20 upwardly, as shown in Figure 2, to cause lower valve face 21 to contact valve seat 21A and to keep upper valve face 22 clear of valve seat 22A. This provides for chamber 23 to communicate with the interior of reservoir 12 while isolating the chamber 23 from the communication with annular vessel 25. In this relative position liquid in reservoir 12 flows into the chamber 23 until the chamber 23 is full. Annular vessel 25 has an open top 26 and an annular base 27 pierced by a bleed hole 28. The vessel 25 is mounted on the lower part of the shuttle 20 so that shuttle and vessel move as a unit relative to the bore 29 in boss 19.

Figures 3 to 5 A toilet cistern 30 is shown in Figure 3 full of water to a level F with the dispenser 11 clipped in position. The valve shuttle 20 is located as shown and described in connection with Figure 2 where the spring 25 serves to draw the shuttle 20 upwardly so that lower valve face 21 contacts the valve seat 21A. In this configuration the working fluid X in the reservoir 12 is isolated from the water in the cistern. The annular vessel 25 is flooded by the surrounding water.

Once cistern 30 is flushed the water level drops rapidly from level F to level E as shown in Figure 4. The annular vessel 25 retains water with a consequent increase in weight once the main water level has dropped below the device 11. This increase in weight is sufficient to overcome the action of spring 25 so drawing lower valve face 21 clear of seat 21A and drawing down the valve shuttle 20 so that upper valve face 22 seats on valve seat 22A. As a result the reservoir 12 is isolated from the outside of the device 11 and the measure of working fluid held in chamber 21 is released to flow into the annular vessel 25 where it mixes with the water in the vessel 25 as it leaks out of bleed hole 28.

Figure 5 shows the cistern 30 as it refills following a flushing action. The bleed hole 27 is sized so that water can drain out of the annular vessel 25 before the cistern can refill. This provides for effective mixing of working fluid with the bulk of liquid in the cistern 30. The drainage of water from the annular vessel 25 results in an effective decrease in the weight of the vessel 25. Consequently the spring 23 exerts sufficient force to lift the shuttle 20 so as to close valve 21 onto valve seat 21A and to open valve 22 from valve seat 22A. A fresh supply of working fluid is thereby enabled to enter the chamber 21 to await the next flushing cycle. Once the cistern 30 has refilled the relative components of the system are restored to that shown in Figure 3.

The embodiment provides an effective means of dispensing a measured of material into a cistern subject to emptying whether at regular or irregular intervals or rarely or frequently.

Claims

1A dispensing unit for a cistern subject to periodic flushing including: an outlet from the unit through which material to be dispensed is supplied; a reservoir of material to be dispensed in discrete doses; and a dispensing shuttle which acts to dispense a predetermined measure of material from the reservoir to the outlet each time a flushing action occurs

2 A dispensing unit as claimed in Claim 1 wherein the dispensing shuttle contains a chamber corresponding in volume to the predetermined measure and is displaceable between a first position wherein it is in communication with the reservoir and isolated from the outlet, and a second position where the chamber is isolated from the reservoir and communicates with the outlet.

3 A dispensing unit as claimed in Claim 2 wherein the shuttle is connected to a container which has been filled, in whole or in part, by water supplied from the cistern but is not immersed in water in the cistern acts to draw the shuttle from the first to the second position to enable material in the chamber to flow into the container; the container containing a bleed means whereby liquid in the container can pass out of the container into the cistern.

4 A dispensing unit as claimed in Claim 3 including a resilient biassing means acting on the shuttle so that with the container substantially empty the biasing means acts to restore the shuttle from the second position to the first and to maintain it in the first position.

5 A dispensing device as hereinbefore described with reference to and as illustrated in Figures 1 to 5 of the accompanying drawings.