GB2423311A

GB2423311A - Device for automatically dispensing a chemical into a toilet cistern

Info

Publication number: GB2423311A
Application number: GB0503109A
Authority: GB
Inventors: Tan Hang Meow Tan
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-02-15
Filing date: 2005-02-15
Publication date: 2006-08-23
Anticipated expiration: 2025-02-15
Also published as: GB0503109D0; GB2423311B

Abstract

A device for automatically dispensing a chemical into a toilet cistern comprises an open-topped container containing a water-soluble solid chemical, a cap member having a fluid retaining depression (25) with a central drain opening (28) and at least one aperture (24) in a side wall, wherein the aperture (24) is positioned at a point which is lower than the lowest part of the depression (25).

Description

* 2423311

DESCRIPTION

An improved auto dispenser

FIELD OF INVENTION

The invention relates generally to an apparatus for distributing a watersoluble chemical to surrounding water, and more particularly to a toilet cleaner unit for distributing a chemical to water therein a toilet cistern tank.

BACKGROUND OF INVENTION

This invention represents novel enhancement to the device first disclosed in Great Britain patent GB2257722. As such, this invention disclosure is intended to act in a manner complementary to that initial patent.

The focus of both that patent and this disclosure is the toilet cleaner. Prior art toilet cleaners are widely used. Generally speaking, such cleaners are found in three different forms; one a simple solid block that resides submerged inside the cistern to gradually dissolve and hence release the cleaning agent. The second type attaches to the rim of the toilet bowl and thus dispenses its cleaning agents only when the toilet is flushed. Both of these designs carry inherent problems and limitations. The submerged-block device dissolves at a steady rate independent of the rate of use of the unit - hence being potentially wasteful of product if the toilet is used only infrequently. The rim-attached device, on the other hand, dispenses only when the toilet is used, but the performance of this design is inadequate since only a part of the circumference of the rim of the toilet bowl receives any of the cleaning agent dispensed from the product.

A third prior art toilet cleaner (50) is illustrated in Figure 1. This prior art toilet cleaner (50) takes the shape of an elongated open top cylinder (55), which is partially filled with a quantity of a solid water soluble cleansing and sanitizing chemical (54).

This and other prior art toilet cleaning chemicals normally carry a coloured pigment, so that it will impart a visible color to the flushing water when the chemical dissolves. At the throat of the cylinder (55) is a small opening (51), which is located roughly three quarters of the height of the cylinder (55) from the base. The level of the chemical medium can preferably be at the same level, or is at a distance below the level where the opening (51) at the throat is located. The top of the cylinder (55) gradually narrows to form an opening (52) of a smaller diameter than that of the base cylinder (55). At a position on the rim of this top opening (52), which is diametrically opposite to the position of the opening (51) at the throat, there is provided is a lip (not shown), by which the cylinder (55) can be suspended from an edge of a cistern tank using a length of flexible element (not shown).

The prior art toilet cleaner (50) can thus be positioned so that the level where the opening (51) at the throat is located is at a distance below the actual water level (53) in the cistern tank. Most toilet cleaner manufacturers indicate a water level marking (56) on the cylinder (55) above the opening (51) at the throat. Some brands of toilet cleaners prefer to submerge the entire cylinder (55) so that the open top (52) is placed approximately 10 to 20 mm below the actual water level (53). Water enters the cylinder through the opening (51) at the throat, and also through the open top (52) if it is fully submerged. The water- soluble chemical then dissolves in it to form an active solution with a visible coloration. The intensity of the coloration indicates the strength of the chemical dissolved in the flushing water.

With this and first prior art toilet cleaner, there is no indication of the actual length of time that each cleaner can last since the active solution flow is not monitored. At times, there will be unnecessary discharged of the active solution resulting in a excessively deep coloration of the flushing water. As the chemical content gradually reduces with use, the active solution so formed may become chemically weak or it may not be displaced from the toilet cleaner unit.

The GB2257722 patent largely overcomes both this consistency problem offering users an essentially constant discharged of product every flush, irrespective of the amount of time that has passed between flushes - and the problem of covenng all of the water-washed surfaces of the toilet with the cleaning chemicals as may be found in the second type of prior art device. Several design issues remain present in this patent, however. Such issues include the fact that the amount of product dispensed from the container is affected by the presence of turbulence in the water around the container. Hence, if a user places the device close to the region where water enters the cistern, there is a likelihood that excessive product may be dispensed. Another potential issue with the initial design is that it will not dispense product correctly unless it is positioned in specific orientation. This limitation again means that is the container is placed close to the cistern water entry point, there was the potential that it could be knocked over.

A third potential limitation of the initial design is that, because the container is designed to sit at the bottom of the cistern, when all of the product has been discharged and the user is required to remove it, it is potentially necessary for them to get their hands wet.

SUMMARY OF INVENTION

In addition to the initial principal object of the present invention to dispense only a controlled amount of the active solution in each flushing of the cistern tank, therefore economising the use of chemical, the new design is intended to eliminate the problems of vulnerability to turbulence, potential to be knocked over and ease of removal from cistern.

As in the original patent, a particular and associated object of the invention is to provide an improved apparatus for dispensing a chemical medium at a controlled and consistent rate over the useful life of the apparatus as represented in a stated number of flushing.

All parts of construction for the present invention are preferably made from a synthetic plastic material by injection moulding method. However other materials that will not corrode when in contact with water and other formation methods can be used.

To these and other ends, the present invention comprises, in its broadest from as illustrated in Figures 2 and 3: an open top container (40), preferably cylindrical in shape, containing a water- soluble solidified chemical medium (43); a round cap member (20), adapted with a centrally placed fluid retaining depression (25), embedded in its top surface and at least one opening (24) in its side wall wherein there is a difference in height (12) between the lowest portion of the depression and the base of the slot(s), and used to cap the top openings of the said container (40); a circular diaphragm (30), with an opening (32) which covers the top opening of the said ronner (40) and is placed in position between the round edges of the cap member (20) and the container (40); an optional thin walled conically shaped plug insert (11) to engage a drain opening passageway (26) for the fluid retaining depression (25) in th expei sr t member (20), and the counter-weight (44).

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing objectives, features and other advantages of the invention will be further understood upon consideration of the following detailed description of a preferred embodiment of the invention, taken in conjunction with the accompanying drawing, wherein Figure (1) is a cross sectional view of a prior art toilet cleaner unit.

Figure (2) is a cross-section view of the various parts making up a dispenser unit according to the present invention; Figure (3) is an assembly view of the various parts making up a dispenser unit according to the present invention; Figure (3A) is an assembly view of the various parts making up a dispenser unit according to the improved present invention showing a modification to include a protruding weight location feature in the base of the open-top container; Figure (3B) is an assembly view of the various parts making up a dispenser unit according to the improved present invention showing a modification to include a hook shape protrusion; Figure (4) is a cross-section view of the dispenser unit showing alternative nozzle arrangements; Figure (5) is a cross-section view on the act of flowing for the invention dispenser unit; Figure (6) is a top plan view of the dispenser unit according to the improved present invention with and without air venting hole; Figure (7) is an alternative form of the dispenser unit according to the invention showing an alternative geometry and base weight configuration; Figure (8) is a cross-section view of the improved present invention dispenser unit showing an alternative base configuration offering a self-righting capability; Figure (9) is a cross-section view of the improved present invention dispenser unit showing a further alternative base configuration offering a self-righting capability; Figure (10) is a cross-section view of the improved present invention dispenser unit showing an alternative external attachment feature; Figure (11) is a cross-section view of the assembled dispenser showing optional shroud features;

DETAILED DESCRIPTION

The following detailed description of a presently preferred embodiment of the invention is in the environment of an apparatus for distributing water-soluble chemical medium to water contained therein a toilet cistern tank, It will be understood that the invention is considered to have a broader application than just this particular environment.

With reference to Figures 2 and 3, the auto dispenser unit may include a plug insert (10), engaging in a drain opening (28) of a fluid retaining depression (25) formed in the top of a round cap member (20), capping a base container (40), carrying a chemical medium. The base container (40) can be covered by a diaphragm (30) engaged and trapped circumferentia(ly between the edges of the cap member (20) and the container (40). Active chemical ingredients are to be filled at the bottom part (43) of the container. The cap member (20) contains at least one slot (24). This slot or slots (24) are formed in the lower portion of the side wall (27a) of the cap member (20), adjacent to the circular skirt (27b).

Importantly there is a difference in height (12) between the lowest portion of the depression (25) and the base of the slot(s) (24). This difference in height provides the driving pressure that will cause the dispenser to dispense a fixed amount of chemical following each flush of the toilet.

The fluid retaining depression (25), formed preferably centrally in the cap member (20), opens onto the top surface with a substantially annular rim surrounding the formed opening of the fluid retaining depression (25).

In one configuration, the depression (25) may feature an elongated nozzle (26) which extends downward to the base container (40). In configurations featuring this nozzle, it is again the difference in height between the lowest point on the nozzle and the highest point on the slot (s) (24) that will influence the dispensing performance of the device. One of the reasons for including the separate nozzle component may be to allow a degree of flexibility in the dispensing of the device - increasing or decreasing the height of the nozzle will correspondingly decrease and increase the amount of chemical dispensed during each toilet flush.

The Figures also show the presence of weighting means (44) and further means of locating and retaining said weighting means at the base of the container (40). The purpose of the weighting means is to ensure that the dispenser has an overall average density greater than water, so that it sits at the base of the cistern. It is desirable that once all of the solid chemical (43) has been used that the dispenser floats to the top of the cistern in order to facilitate ease of removal by the user.

The transition from sinking to floating occurs due to the presence of airtrapping means at the top of the cap (20). Said means may be achieved by a number of different methods, the simplest being to ensure that the highest point on the slot(s) (24) is lower than the highest internal point inside the cap. The difference between these two heights is configured such that the overall relative density of the dispenser transitions from greater than unity when the solid chemical (43) is present, to less than unity when the solid chemical has all been used.

Referring specifically to Figure (2), the container (40) is substantially an open-topped tub (41).

Preferably this container has a diameter (D) greater than the height (H) of the dispenser unit in order to achieve better stability in the base of the cistern, although in some configurations the ratio between 0 and H may vary. The complete dispenser unit is meant to be placed fully submerged inside at the base of the toilet cistern tank. The combination of aspect ratio and base weight is designed in such a way as to ensure that the dispenser unit will not float while the active chemical agent is still present and will not topple sideway to spill out active chemical ingredients.

As such, the dispenser unit will remain in a substantially vertical position irrespective of the movement of the water inside the cistern tank Figures (3), (3A) and (3B) illustrate two of a number of possible means of attaching the weighting means to the base of the container. Figure (3) illustrates the case in which the weighting means is a disc (44). This disc is constructed of a dense material and contains means by which it may be retained on the base of the container. In the figure, the means of retention is an interference fit between a hole drilled in the disc and a corresponding, integral protrusion emerging from the base of the container. Figure (3A) shows an alternative arrangement wherein the weighting means comprise at least one glass marble (44). Said marbles are retained in place using a combination of protruding features (44a, 46) and an interference fit washer (45) located onto one of the protrusions - in this case a circular center-post (46). Figure (38) shows yet another weight- retaining means, this time at least one glass marble is held in position by a series of flexible angled protrusions emerging from the base of the container.

Referring again to Figure (3), the lower open mouth of the cap member (20) enlarges to a circular skirt (27a) of a larger diameter. Positioned inwardly of the skirt (27b), there may be a plurality of equally space vertical retainer studs (23), which collectively form a circle of a smaller diameter than the inside diameter of the skirt (27b). A preferred number is eight while in the Figure (3), four has been shown. The annular gap between these two diameters of the retainer studs (23) and the skirt (27b) engages in interference fit with the upper rim of the base container (41). With this clip- on arrangement, the cap member (20) removably covers the top opening of the container (40).

Figures (2) and (3) show a flat diaphragm (30). This diaphragm can be optionally used to cover the top open end of the container (40). The diaphragm can be engage and trapped in position between the edges of the cap member. (20) and the base container (40) by the dip-on arrangement of the retainer studs (23). The removable diaphragm (30) can be used to divide the enclosed space within the container (40) into an enclosed space (31) taking a contoured shape formed by the underside convex surface of the funnel (25), the sloping surface of the nozzle (26) and the diaphragm (30); and another endosed space (42) taking the shape formed by the diaphragm (30) the tub (41) and the chemical medium (43). The diaphragm has the function of controlling the amount of chemical medium dispensed after each flush. As such, the diaphragm may be manufactured from a variety of different materials, possessing different levels of both flexibility and porosity.

On the outer circumference of the diaphragm (30) is a plurality of four equally spaced circular notches (31). A hole (32) is cut at the centre of the diaphragm (30). This hole may be circular or a variety of other shapes. The diameter of the hole (32) also helps to determine the diffusion rate of the chemical medium (43) carried in the base container (40), when the dispenser unit is resting underwater. The larger this diameter is, the greater will be the diffusion rate.

During the flushing operation, this diaphragm (30) additionally serves to stabilize the fluid flow within the auto dispenser unit, and thus prevent an excessive loss of the chemical through the turbulence of the fluid, caused by the flushing action. As such, the diaphragm may feature local grooves and protrusions that serve to reduce local turbulence around the hole (32).

Figure (4) shows how the elongated nozzle (26) may be taper-sided or parallel-sided. In either case, in one configuration of the invention, the consumer may vary the height of the nozzle (and hence the height (12) in order to control the rate and amount of product dispensed during each flush. In this manner, it becomes possible to offer consumers more than one operating setting for the unit - e.g. economy' and heavy' operating conditions.

Referring to Figure (5), the following description is now particularly given to show how the auto dispenser unit operates: Consider a situation where the auto dispenser unit is placed at the base of the cistern tank and the flushing water is filling up the tank. Water will enter the unit through the apertures (24) in the side wall of the cap member (20), and into the enclosed spaces (31) and (42). As water comes in contact with chemical medium (43), active solution is formed and water turns the colour of the chemical medium.

Some active solution will move upward through the fluid passageway (28) and (12), into the concavity of the fluid retaining depression (25). The amount of active solution so formed is determined by the volume of the enclosed spaces (31) & (42).

During flushing, when the actual water level inside the cistern tank comes below that level of the apertures (24) in the sidewall, the water contained in the fluid retaining depression (25) will move down by gravity through the drain opening due to the height difference (12) and the fluid passageway, displacing active solution of similar amount from the enclosed space (42) into (31) and flows out of the dispenser via the opening (24) into the surrounding water subsequently.

Figure (6) illustrates the alternative possibility that at least one air venting holes (21) may also be included in the top of the cap (20). Such features may be beneficially included in situations where it is not desired to have the dispenser become buoyant after the active chemical has been exhausted. Trapping of air in the top of the cap may cause instability of the dispenser in such situations, and so the vent or vents may be included to prevent this eventuality. Figure (6a) also illustrates the prefen'ed version of the unit wherein the air venting holes are omitted from the design.

Referring to Figure (6). In this alternative configuration of the unit, the base of the container is profiled in such a way that the overall unit acquires self-righting properties. As suggested by the figure, this may comprise a hollow portion at the base of the container. This hollow portion permits the counter-weight (44) to move relative to the base in order to deliver the self-righting properties.

Figure (7) illustrates and alternative configuration of the dispenser in which the height is greater than the diameter. Such a configuration may be advantageous in smaller sized slim-line' cisterns.

The figure also shows an alternative weighting means - in this case a dense material shaped substantially the same as the base of the container so that it is retained in position simply due to the similarity between its shape and that of the base of the container. This high aspect ratio dispenser geometry may also have a bottom holder component (44a) that serves to locally increase the base area for the purposes of improving overall stability of the device.

I

Figures (8) and (9) illustrate two alternative base configurations, both of which are intended to provide self-righting capability to the dispenser. In both Figures, the base of the container (4) has a curved profile, and a weighting means that serves to cause the device to want to return to an upright position following disturbance by, say, incoming water. In the case of Figure (8), this weighting means is fixed into the base of the container, while in Figure (9), the weight is retained inside a hollow cavity and is free to move in an appropriately constrained fashion.

Referring to Figure (10), after the active ingredient has been expended and the consumer wishes to remove the empty container from the cistern, the unit may incorporate a protruding feature in order to facilitate easy removal from the cistern. This protruding feature may or may not protrude above the surface of the water in a full cistern. In a preferred configuration, the protruding feature is flexible to facilitate easy packaging of the product, and such that the protruding feature may be hooked over the top edge of the cistern.

An alternative means of recovering the expended product from the cistern involves indusion of the aforementioned zone (24a) to trap air such that after the product has been expended the net density of the empty container becomes less than that of the water so that the unit floats to the surface of the water in the filled cistern.

Referring to Figure (11), in order to protect the unit from the adverse effects of turbulence during filling of the cistern, the cap (20) may be profiled in such a way that the slot (24) and/or the fluid retaining depression (25) are shrouded by a non-air-tight protective feature. Such shroud features may fully surround the slot and the fluid retaining depression or may be local features. Preferably such features should be formed integrally during the manufacture of the round cap (20).

While the invention has been described in relation to a particular embodiment, those skilled in the ait will recognise modifications of materials, structure and the like as coming within the scope of the present invention now claimed.

Claims

1) An auto dispenser unit for dispensing a controlled quantity of a chemical medium for use in a toilet cistern tank charactenzed by an open top container, carrying the said chemical in water- soluble, solid form, and a cap member, adapted for removable attachment to the said container and having a fluid retaining depression, which opens onto its top surface, and which includes a means of releasing said fluid in a controlled manner downwards into the container, and having at least one chemical medium release aperture formed in its side wall, wherein the vertical position of the chemical medium release aperture is lower than the lowest point within the fluid retaining depression.

2) An auto dispenser unit according to Claim (1) wherein a diaphragm containing a hole at its center, covers the open top end of the container, and is engaged and trapped in position by the edges of the cap member and the container.

3) An auto dispenser unit according to Claim (2) wherein the diaphragm may be non-porous or semi-porous to water and may feature a number of grooves or protrusions.

4) An auto dispenser unit according to previous Claims wherein a thin walled, hollow plug insert engages the fluid release means of the fluid retaining depression, therefore extending the fluid passageway defined in the nozzle of the fluid retaining depression and the nose of the plug insert.

5) An auto dispenser unit according to Claim (4) wherein the plug shaped insert is parallel-sided and interference press-fit into the fluid retaining depression passageway.

6) An auto dispenser unit according to Claim (4) wherein the plug shaped insert is conically shaped.

7) An auto dispenser unit according to Claim (4) wherein the cap member is integrally attached to the base of the container.

8) An auto dispenser unit according to Claim (4) wherein the plug shape insert is rotatable or movable in order to permit a variation in the flow of fluid through the fluid release means of the fluid retaining depression.

9) An auto dispenser unit according to previous Claims wherein the plug shaped insert is deleted and the fluid release means at the base of the fluid retaining depression becomes at least one hole.

10) An auto dispenser unit according to previous Claims wherein the base of the open top container bears a dense weighting means which may be separate from or integral to the container.

11) An auto dispenser unit according to Claim (10) wherein the base of the container features at least one protrusion to hold the weighting means either with or without the presence of an additional retaining means.

12) An auto dispenser unit according to previous Claims wherein the cap features at least one air venting means formed in said top surface.

13) An auto dispenser unit according to previous Claims wherein the highest point on the chemical release medium aperture(s) is lower than the highest internal feature of the cap in order to trap an amount of air such that the dispenser becomes buoyant after the exhaustion of the solid chemical medium.

14) An auto dispenser unit according to previous Claims containing additional features that will trap air in such a way that device will float when the product has been consumed' in order to facilitate retrieval of the product from the cistern after it has finished delivering its useful function.

15) An auto dispenser unit according to previous Claims wherein the base of the open top container has a curved profile, on the inside of which a fixed or loose weight is able to move freely in a manner that ensures the container always returns to rest in a vertical orientation following the application of an external disturbance force.

16) An auto dispenser unit according to previous Claims wherein the unit comprises other geometric configurations and weights so that the unit always returns to its intended orientation following a disturbance when full or partially submerged.

17) An auto dispenser unit according to the previous Claims wherein the fluid release means hole(s) is of spiral, and/or tapering form.

18) An auto dispenser unit according to previous Claims wherein the fluid retaining depression is covered by removable adhesive cover prior use.

19) An auto dispenser unit according to previous Claims wherein the at least one chemical release medium aperture is surrounded by a nonairtight shroud that serves to prevent the aperture from direct exposure to turbulent water flows within the cistern.

20) An auto dispenser unit according to previous Claims containing additional features that protrude from the unit in order to facilitate easy removal from the cistern.

21) An auto dispenser unit according to the accompanying drawings.