WO2019013710A1

WO2019013710A1 - Toilet bowl

Info

Publication number: WO2019013710A1
Application number: PCT/SG2018/050345
Authority: WO
Inventors: Yong Chien CHAN
Original assignee: Rigel Technology (S) Pte Ltd
Priority date: 2017-07-13
Filing date: 2018-07-11
Publication date: 2019-01-17
Also published as: SG10201705779YA

Abstract

The present invention relates to a toilet bowl and a flush toilet thereof. In particular, there is a toilet bowl comprising at least one fluid outlet disposed on an inner surface of the toilet bowl, the fluid outlet arranged to output a flush fluid at a predetermined flow rate; and a fluid guide arranged in fluid communication with the fluid outlet to receive the flush fluid, the fluid guide arranged around a portion of the inner surface of the toilet bowl to direct flush fluid around an upper inner surface of the toilet bowl.

Description

TOILET BOWL

Field of Invention

The present invention relates to a toilet bowl and a flush toilet thereof. Background Art

The following discussion of the background to the invention is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge of the person skilled in the art in any jurisdiction as at the priority date of the invention.

Toilets typically comprise a bowl that is configured to receive waste from an individual. Water can be introduced into the bowl in order to wash the surfaces of the bowl and transfer the waste through an outlet. However, as water is a scarce natural resource, usage of traditional toilets that require a relatively large volume of water for a single flush is undesirable. As such, there is a need to develop toilets that require a relatively small volume of water.

For toilets that use a relatively small volume of water, one challenge is to retain the efficiency of waste removal, while keeping the surfaces of the bowl clean. Consequently, toilets that comprise rims for directing water into the outlet have been developed. The rim may be positioned under the top of the bowl and include several holes in an underside of the rim, through which water may flow in order to remove any waste that remains on the surfaces of the bowl. A typical configuration includes a box- type rim, which may have a closed, hollow cross-section through which water may flow. Another example of a conventional rim design is an open-type rim, which may have a cross-section shaped like an inverted "U".

Various problems can arise from the use of toilet rims. For instance, waste or other undesired matter (e.g. bacteria, dirt) may get trapped underneath the rim and in the holes located at the underside of the rim. As a result, waste or other undesired matter may collect, thereby affecting hygiene levels. Furthermore, losses to the energy of the flowing water can occur when water goes across the rim and distributes among the holes located at the underside of the rim, the losses in the form of sound energy such as noise. As such, the use of rims can reduce the energy of the flowing water and significantly reduce the efficiency of waste removal.

In light of the above, there exists a need to develop a toilet bowl and a flush toilet thereof that ameliorates or overcomes the above disadvantages.

The present invention seeks to provide a toilet bowl and a flush toilet thereof that addresses the aforementioned need at least in part.

Summary of the Invention

In an aspect of the invention, there is provided a toilet bowl comprising at least one fluid outlet disposed on an inner surface of the toilet bowl, the fluid outlet arranged to output a flush fluid at a predetermined flow rate; and a fluid guide arranged in fluid communication with the fluid outlet to receive the flush fluid, the fluid guide arranged around a portion of the inner surface of the toilet bowl to direct flush fluid around an upper inner surface of the toilet bowl. Preferably, the toilet bowl further comprises a rim having a first flange protruding from the inner surface of the toilet bowl to form part of the fluid guide.

Preferably, the fluid guide comprises a second flange protruding from the inner surface of the toilet bowl, wherein the first flange and the second flange form a channel for the flush fluid to flow therebetween. Preferably, the thickness of the fluid guide changes across the upper inner surface of the toilet bowl.

Preferably, the thickness of the first flange changes across the upper inner surface of the toilet bowl.

Preferably, the first flange comprises an edge inclined towards the second flange. Preferably, the portion of the second flange adjacent to the edge has a smaller protrusion relative to the other portions of the second flange.

Preferably, the second flange comprises a rounded edge. Preferably, the at least one fluid outlet comprises a main fluid outlet and a plurality of small fluid outlets.

Preferably, the fluid guide extends more than half the parameter of the toilet bowl. Preferably, the parameter is a circumference of the toilet bowl.

Preferably, the main fluid outlet comprises a width of about 35 mm to about 40 mm.

Preferably, the main fluid outlet has a length of about 40 mm to about 45 mm.

Preferably, the main fluid outlet is off-centre and disposed on the upper inner surface of the toilet bowl. Preferably, the plurality of small fluid outlets are located on a back rim disposed on a rearmost portion of the toilet bowl.

Preferably, the plurality of small fluid outlets are angled such that flush fluid from the small fluid outlets move in the same direction as the flush fluid from the main fluid outlet. Preferably, the main fluid outlet is located at about 45 degrees away from the centre of the toilet bowl.

In another aspect, there is provided a flush. toilet comprising a toilet bowl as described above.

Other aspects of the invention will become apparent to those of ordinary skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying drawings.

Brief Description of the Drawings

The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 illustrates the cross-sectional view of a flush toilet in accordance with an embodiment of the invention; Fig. 2 illustrates the top view of the flush toilet of Fig. 1 as viewed from Vi of Fig. 1 ; Fig. 3 illustrates a perspective view of the flush toilet of Fig. 1 ;

Fig. 4 illustrates the cross-sectional view of the flush toilet of Fig. 1 as viewed from V2 of Fig. 1 ;

Fig. 5 illustrates another perspective view of the flush toilet of Fig. 1 ;

Fig. 6 is a photograph of the flush toilet of Fig. 1 in operation;

Fig. 7 illustrates an enlarged view of a portion of the flush toilet of Fig. 1 , showing the guiding means angled downwards into the bowl to form an edge;

Fig. 8 illustrates an enlarged view of a portion of the flush toilet of Fig. 1 , showing the plurality of small fluid outlets that are angled such that fluid from the small fluid outlets move in the same direction as the fluid from the main outlet; and

Fig. 9 illustrates the top view of the flush toilet of Fig. 1 as viewed from Vi of Fig. 1 , showing the width and length of the small fluid outlets. Other arrangements of the invention are possible and, consequently, the accompanying drawings are not to be understood as superseding the generality of the preceding description of the invention.

Description of Embodiments of the Invention

Particular embodiments of the present invention will now be described with reference to the accompanying drawings. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention. Other definitions for selected terms used herein may be found within the detailed description of the invention and apply throughout the description.

Additionally, unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one or ordinary skill in the art to which this invention belongs. Where possible, the same reference numerals are used throughout the figures for clarity and consistency.

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. Furthermore, throughout the specification, unless the context requires otherwise, the word "include" or variations such as "includes" or "including", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

The terms "x-axis", "y-axis" and "z-axis" refer to the orientation of the toilet bowl. Throughout the specification, unless the context requires otherwise, the toilet bowl is facing front (or forwards) along the x-axis, the small fluid outlets are facing downwards in the negative y-axis and the width of the toilet bowl is along the z-axis.

The term "main fluid outlet" used throughout the specification refers to a hole (or orifice, opening, channel, etc.) for dispensing fluid such that the amount of fluid from the main fluid outlet is greater than the combination of fluid dispensed from the small fluid outlets.

The term "small fluid outlet" used throughout the specification refers to a hole (or orifice, opening, channel, etc.) for dispensing fluid such that the amount of fluid from the small fluid outlet is significantly smaller than the fluid dispensed from the main fluid outlet. As such, the amount of fluid dispensed from a plurality of small fluid outlets would be less than the amount of fluid dispensed from the main fluid outlet.

In various embodiments or combinations, the fluid dispensed from the main fluid outlet may be more than and including (or at least) 50%, 60%, 70%, 80%, 90% or 95% of the total fluid dispensed from the small fluid outlets. Other embodiments are possible and the afore-mentioned list is not to be construed as an exhaustive list.

The term "width" when used in the context of an outlet refers to a measurement of an outlet (or hole, orifice, opening, channel, etc.) from one side of the outlet to its other side. When used in the context of a small fluid outlet, the width is measured along the x-axis. For example and as illustrated in Fig. 8, the width of small fluid outlet 32c is the measurement between W and W, which represents the measurement of one side of the small fluid outlet 32c to the other side as measured along the x-axis. The term "length" when used in the context of an outlet refers to a measurement of an outlet (or hole, orifice, opening, channel, etc.) from its top to its bottom. When used in the context of a small fluid outlet, the length is measured along the z-axis. For example and as illustrated in Fig. 8, the length of small fluid outlet 32b is the measurement between L and L', which represents the measurement of one side of the small fluid outlet 32b to the other side as measured along the z-axis.

In accordance with an embodiment of the invention and as shown in Fig. 1 to 9, there is a flush toilet 10 for removal of waste, in particular human waste, using a fluid (or flush fluid) such as water or cleansing liquid which may be stored in a cistern of a flush toilet and discharged via at least one fluid outlet to clean the toilet bowl, and will be described in such a context. As will be explained in greater detail below, various embodiments of the flush toilet 10 may advantageously play a role in achieving efficient waste removal using a relatively small volume of water, while keeping the surfaces of the toilet bowl clean. Importantly, the toilet bowl can be cleaned in a relatively silent manner due to minimization of losses such as noise and prevention of splashing of water out of the bowl.

As shown in Figs. 1 and 2, the flush toilet 0 comprises a toilet bowl 20, the toilet bowl 20 comprising at least one fluid outlet disposed on an inner surface of the toilet bowl 20. In various embodiments, the at least one fluid outlet comprises a main fluid outlet 22 disposed on an inner upper surface of the toilet bowl 20 and a plurality of small fluid outlets 32 disposed on a back rim 30 of the toilet bowl 20, such that water from the cistern (not shown) can enter the toilet bowl 20 at a predetermined flow rate. In various embodiments, the predetermined flow rate has a flow rate of at least about 0.85 litres per second at the main fluid outlet 22.

In various embodiments, the toilet bowl 20 further comprises a fluid guide 24 arranged in fluid communication with the at least one fluid outlet to receive the water from the main fluid outlet 22. In various embodiments, the fluid guide 24 extends more than half the parameter of the toilet bowl 20. Preferably, the parameter is a circumference of the toilet bowl 20. As shown in Figs. 1 , 3, 4 and 5, the toilet bowl 20 comprises a rim 26 having a first flange 26a protruding from the inner surface of the toilet bowl 20 to form part of the fluid guide 24. The rim 26 is configured such that it extends around the parameter of the toilet bowl 20. Consequently, water may be prevented from splashing out of the toilet bowl 20. Furthermore, by extending around the parameter of the toilet bowl 20, the rim 26 may also function as a fluid guide for the water, thereby advantageously directing part or most of the fluid output from the main outlet 22 around the parameter of the toilet bowl 20. Preferably, the parameter is a circumference of the toilet bowl 20. The fluid guide 24 further comprises a second flange 24a protruding from the inner surface of the toilet bowl 20, wherein the first flange 26a and the second flange 24a form a channel for water to flow. Preferably, the second flange 24a is integral with the inner surface of the toilet bowl 20. In some embodiments, the second flange 24a may be a region of gentle gradient or slope relative to the rest of the inner surface (20a, 20b) of the toilet bowl 20, the gentle gradient or slope providing sufficient friction to direct part or most of the fluid output from the main outlet 22 around the parameter or circumference of the toilet bowl 20. As the fluid guide 24 is in fluid communication with the main fluid outlet 22, once the main fluid outlet 22 outputs water, water from the main fluid outlet 22 is directed around the upper inner surface of the toilet bowl 20 via the fluid guide 24 in a spiral manner (or whirl wash effect), as indicated by the arrows in Figs. 2 and 6. Consequently, any waste on the inner surface (20a, 20b) of the toilet bowl 20 is washed down by the water and transferred through a waste outlet 40 using a relatively small amount of water.

In various embodiments, the positioning of the main fluid outlet 22 may be configured such that water dispensed from the main fluid outlet 22 is directed towards the inner surface (20a, 20b) of the toilet bowl 20 in a spiral manner (i.e. around the circumference of the toilet bowl 20 in successive decreasing circumference until water is drained at the waste outlet 40). In particular, a spiral flow can be created due to the main fluid outlet 22 being positioned at an angle from the centre C of the toilet bowl 20 i.e. the main fluid outlet 22 is off-center, and disposed on the upper inner surface of the toilet bowl 20. For instance, and as shown in Fig. 2, the main fluid outlet 22 is disposed on the upper portion of inner surface 20b of the toilet bowl 20. As indicated by the centre line L in Fig. 2, which cuts through the rearmost portion of the toilet bowl 20, the main fluid outlet 22 is positioned at an angle a, preferably 45±3 degrees, from the centre C of the toilet bowl 20 i.e. the main fluid outlet 22 is shifted to one side of the toilet bowl 20.

In various embodiments, the main fluid outlet 22 is not disposed on the centre line L. This is because the whirl wash effect would be compromised, in these embodiments, the main fluid outlet 22 is disposed off-centre to enhance the whirl wash effect. In particular, when the main fluid outlet 22 is disposed on the centre line L and the rearmost portion of the toilet bowl 20, water dispensed from the main fluid outlet 22, which may have a substantially strong flow rate, may contact an adjacent part of the rearmost portion of the toilet bowl 20 in such a manner that significant splashing may occur. In other words, the adjacent part of the rearmost portion of the toilet bowl 20 may block the flow path of the water dispensed from the main fluid outlet 22, thereby causing splashing. In various embodiments, the dimensions of the main fluid outlet 22 may be configured such that most of the water in one flush cycle is dispensed from the main fluid outlet 22. Furthermore, the dimensions of the main fluid outlet 22 is sufficiently large so that water is dispensed smoothly with less losses of the energy of the flowing water to friction and noise. In particular, the dimensions of the main fluid outlet 22 may be sufficiently large so that splattering (i.e. turbulence) is minimized or eliminated. Increased dimensions of the main fluid outlet 22 may allow greater retention of energy of the flush for a longer period, as well as a reduced likelihood of water splashing out of the toilet bowl 20. Based on a continuity equation of incompressible fluids mathematically expressed as: Q = Av

where Q is the volume flow rate of the fluid measured in cubic metres per second; A is the cross sectional area where the fluid can flow measured in square metres; v is the flow velocity of the fluid measured in metres/seconds, the volume flow rate of a fluid should be kept constant. As such, a smaller cross sectional area may result in a faster fluid flow, which will result in the fluid (water) reaching further around the parameter of the toilet bowl 20. However, the smaller cross sectional area may increase loss of energy of the flowing water to friction and noise, as well as increase the chances of splattering. Accordingly, the dimensions of the main fluid outlet 22 is carefully calibrated to allow water to be dispensed from the main fluid outlet 22 thereby achieving a balance between adequate flow rate and efficient use of the water. The width of the main fluid outlet 22 (with respect to the water dispensed) may range from about 30 millimeters (mm) to about 45 mm. In a preferred embodiment, the width of the main fluid outlet 22 may be about 35 mm to about 40 mm. The length of the main fluid outlet 22 (with respect to the water dispensed) may range from about 35 mm to about 50 mm. In a preferred embodiment, the length of the main fluid outlet 22 may be about 40 mm to about 45 mm.

The shape of the main fluid outlet 22 may be any suitable shape which allows water to be dispensed, including but not limited to square, round, oval and the like. As shown in Fig. 5 and in a preferred embodiment, the main fluid outlet 22 is positioned near rim 26 and shaped such that it contacts the rim 26 of the flush toilet 10 in a manner which significantly reduces splashing and improves water projection. Specifically, the edge 22a of the main fluid outlet 22 that contacts the rim 26 is preferably rounded so that there is a lower tendency of splashing, as compared to, for instance, a square edge, and water projection is improved. There is a lower tendency of splashing because a rounded edge 22a may provide more shielding at the main fluid outlet 22. The term "shielding" as used herein refers to the prevention of water from spilling over the top of rounded edge 22a i.e. splashing upwards. In comparison, water immediately exiting the main fluid outlet 22 may tend to spread across in all axes and direction in the absence of shielding. Furthermore, due to the surface adhesion properties of water, a rounded edge 22a may facilitate adhesion of the water to the surface of the rounded edge 22a, thereby helping the water keep to the original intended flow path i.e. around the circumference of the toilet bowl 20 in successive decreasing circumference until the water is drained at the waste outlet 40. In contrast, a square edge 22a may have the tendency to break the flow path.

In various embodiments, the fluid guide 24 is configured to direct the path of the water flow. In particular, the thickness of the fluid guide 24 changes across the upper inner surface of the toilet bowl 20 such that the thickness of the fluid guide 24 gradually decreases as it moves in a direction parallel to the rim 26. In various embodiments and as shown in Fig. 5, the first flange 26a of the rim 26 contacts the main fluid outlet 22 at an edge 22a, which is preferably rounded so that there is a lower tendency of splashing, as compared to, for instance, a square edge, and water projection is improved. In various embodiments and as shown in Fig. 7, the other end of the first flange 26a is inclined towards the second flange 24a i.e. downwards into the toilet bowl 20, to form an edge 28. In addition, the portion of the second flange 24a adjacent to the edge 28 has a smaller protrusion relative to the other portions of the second flange 24a. Consequently, the main fluid outlet 22 and the fluid guide 24 synergistically diverts the water downwards and into the toilet bowl 20 such that there is minimal losses to friction and noise and a silent spiral flow or whirl wash effect is created. As such, water dispensed from the main fluid outlet 22 can be directed during a flush cycle, for instance, in the direction indicated by the arrows in Fig. 2 and arrow Fi in Figs. 6 and 9.

In various embodiments and as shown in Fig. 4, the flush toilet 10 is a rimless toilet. Consequently, there may be a reduction in losses to friction and noise compared to toilets that comprise rims having several holes in an underside of the rim, through which water may flow. This is because losses to friction and noise can occur for toilets that comprise rims because water goes across the rim and distributes among the holes located at the underside of the rim. Furthermore, as the flush toilet 10 is rimless, waste or other undesired matter (e.g. bacteria, dirt) would not easily get trapped underneath the rim and in the holes located at the underside of the rim. As such, the hygiene levels and cleanliness of the flush toilet of the present invention may be easier to maintain at a satisfactory level and cleaning underneath the rim, which is relatively difficult to do, is not necessary.

In various embodiments, the flush toilet 10 further comprises a back rim 30 disposed on the rearmost portion of the toilet bowl 20, wherein the back rim 30 is connected to the main fluid outlet 22. The back rim 30 may comprise a plurality of small fluid outlets 32 (32a, 32b, 32c, 32d, 32e) so that water can be dispensed from the small fluid outlets 32 and assist in washing the rearmost portion of the toilet bowl 20.

The spacing, dimensions and shape of the small fluid outlets 32 may be configured to swirl water dispensed from the small fluid outlets 32 around the toilet bowl 20 during a flush cycle, for instance, in the direction indicated by the arrows in Fig. 2 and arrow Fi in Figs. 6 and 9. The plurality of small fluid outlets 32 may be disposed around the back rim 30 in, for instance, a spaced-apart manner. This may advantageously lead to more efficient cleaning of the inner surfaces (20a, 20b) of the toilet bowl 20 because water can be dispensed across a larger surface area of the toilet bowl 20.

The dimensions of each small fluid outlet 32 may be the same or different. The dimensions of each small fluid outlet 32 may be configured such that the amount of water from each small fluid outlet 32 is significantly smaller than the water dispensed from the main fluid outlet 22. As such, the amount of water dispensed from a plurality of small fluid outlets 32 would be less than the amount of water dispensed from the main fluid outlet 22. As shown in Fig. 8, the width W- of a small fluid outlet 32c may range from about 5 mm to about 6 mm. The length L-L^! of a small fluid outlet 32b may range from about 5 mm to about 6 mm.

The shape of the small fluid outlets 32 may be any suitable shape including but not limited to square, round, oval and the like. In a preferred embodiment, the small fluid outlets 32 are generally circular in shape, which advantageously allows water to flow into the toilet bowl 20 when the user initiates a flush cycle. In another preferred embodiment, the plurality of small fluid outlets 32 are angled such that water from the small fluid outlets 32 move in the same direction as the water from the main fluid outlet 22. Consequently, the amount of water dispensed from the main fluid outlet 22 and the plurality of small fluid outlets 32 can combine to form one flush cycle, such that the flush toilet 10 is capable of removing waste and cleaning the toilet bowl 20 using full flush water volumes no greater than an amount, such as about 3.5 liters (L) per flush cycle. In various embodiments, the flush toilet 10 may be capable of having a reduced flush water volume of, for instance, 2.5L per flush cycle. As such, the flush toilet 10 may have a full flush water volume and a reduced flush water volume, such that the two flush water volumes can be selected when desired. While the amount is exemplified as 3.5L per flush cycle, it should be understood that other flush volumes is possible to form other embodiments. In various embodiments, the flush toilet 10 is a wash-down toilet. Advantageously, the water level within the toilet bowl 20 remains relatively constant at all times. When a flush cycle is initiated, water flows from the cistern (not shown) and enters the toilet bowl 20 through the main fluid outlet 22 and plurality of small fluid outlets 32. Consequently, the water washes the inner surface (20a, 20b) of the toilet bowl 20 and keeps the inner surface (20a, 20b) of the toilet bowl 20 clean. At the same time, the water from the main fluid outlet 22 transfers waste through a waste outlet 40 using a relatively small amount of water. The waste outlet 40 is preferably pointed downwards so that gravity can assist in transferring waste through the waste outlet 40. Advantageously, the flush toilet 10 requires a smaller amount of pre-flush water in the bowl 20 as compared to siphonic toilets. This small pre-flush volume manifests itself as a small "water spot", as indicated in Fig. 5 as water spot 50. The water spot 50, or surface area of the pre-flush water in the toilet bowl 20, plays an important role in maintaining the cleanliness of a toilet. As shown in Fig. 5, a relatively small water spot 50 is created above the waste outlet 40. In general, a large water spot increases the probability that waste will contact water before contacting the inner surface of the toilet, thereby reducing adhesion of waste to the inner surface and making it easier for the toilet to clean itself via the flush cycle. However, the flush toilet 10 of the present invention is able to maintain a relatively clean toilet bowl 20 despite having a relatively small water spot 50.

The flush toilet 10 advantageously eliminates the need for the user to initiate multiple flush cycles to achieve a clean bowl 20. Accordingly, the flush toilet 10 is self-cleaning despite making use of a relatively low volume of water for each flush cycle. In some embodiments, the flush toilet 10 is capable of operating at a flush volume of about 3.5L or less, and the water dispensed from the main fluid outlet 22 and plurality of small fluid outlets 32 is adequate for removing the waste efficiently while cleaning the inner surfaces (20a, 20b) of the toilet bowl 20. In various embodiments, the flush toilet 10 may be made of any suitable material such as a glazed ceramic material or plastic material. Preferably, the material allows waste to be more easily flushed and is less prone to soiling and wear.

In various embodiments, the cross-sectional shape of the toilet bowl 20 is longer in the vertical direction than in the horizontal direction to assist in the flushing action using a small volume of water. The shape of the toilet bowl 20 is generally that of an inverted cone or funnel to cause the water introduced by way of the main fluid outlet 22 and small fluid outlets 32 to move towards the water spot 50 to flush the waste away, thereby resulting in a good and effective cleaning performance. Consequently, the flush toilet 10 does not require the use of, for instance, a second main outlet or a pressurized water supply in order to achieve efficient cleaning performance.

In various embodiments, the flush toilet 0 may further comprise a mechanism that enables operation of the flush toilet 10 using at least two different flush volumes.

In various embodiments, there is provided a method of manufacturing a flush toilet 10. The method of manufacturing the flush toilet 10 comprises providing a toilet bowl 20 having various features integrated. In particular, the toilet bowl 20 comprises at least one fluid outlet disposed on an inner surface of the toilet bowl 20. In various embodiments, the method of manufacturing the flush toilet 10 comprises disposing a main fluid outlet 22 on an inner upper surface of the toilet bowl 20 and a plurality of small fluid outlets 32 on a back rim of the toilet bowl 20, such that water can enter the toilet bowl 20 at a predetermined flow rate. In various embodiments, the main fluid outlet 22 is configured to have an edge 22a. In various embodiments, the method further comprises shaping the main fluid outlet 22 such that it contacts the rim 26 of the flush toilet 10 in a manner which significantly reduces splashing and improves water projection. Specifically, the edge 22a of the main fluid outlet 22 that contacts the rim 26 is preferably rounded so that there is a lower tendency of splashing, as compared to, for instance, a square edge, and water projection is improved.

In various embodiments, the method of manufacturing the flush toilet 10 further comprising disposing a fluid guide 24 arranged in fluid communication with the at least one fluid outlet to receive the water from the main fluid outlet 22. In various embodiments, the method further comprises configuring the fluid guide 24 to direct the path of the water flow. In particular, the fluid guide 24 is configured so that the thickness of the fluid guide 24 changes across the upper inner surface of the toilet bowl 20 such that the thickness of the fluid guide 24 gradually decreases as it moves in a direction parallel to the rim 26. In various embodiments, the method comprises disposing a first flange 26a on the rim 26, such that it contacts the main fluid outlet 22 at an edge 22a, which is preferably rounded so that there is a lower tendency of splashing, as compared to, for instance, a square edge, and water projection is improved (Fig. 5). In various embodiments, the method further comprises disposing the other end of the first flange 26a such that it is inclined towards the second flange 24a i.e. downwards into the toilet bowl 20, to form an edge 28 (Fig. 7). In addition, the second flange 24a is configured such that the portion of the second flange 24a adjacent to the edge 28 has a smaller protrusion relative to the other portions of the second flange 24a. Consequently, the main fluid outlet 22 and the fluid guide 24 synergistically diverts the water downwards and into the toilet bowl 20 such that there is minimal losses to friction and noise and a silent spiral flow or whirl wash effect is created.

In Figs. 1 to 9, the flush toilet 10 is shown without a cistern or tank configured to store water. However, it should be understood that flush toilet 10 may be attached to a cistern (not shown). The cistern may be low level, high level or concealed, with a concealed cistern being preferred. In a preferred embodiment, the flush toilet 10 works well with flush valves. Advantageously, the use of flush valves may generate a stronger flush strength and power to flush down waste, thereby using direct water pressure from the water line. It should also be understood that the nature and mechanisms for introducing water into the flush toilet 10, whether a cistern or other source, is not important, as any such cistern or water source may be used with the flush toilet of the present invention. In a preferred embodiment, the flush toilet of the present invention works well with a purely mechanical flushing mechanism. In other words, there is no need for electrical power for flushing to occur. As electricity is not required, there may be a savings in operational costs.

In various embodiments, the flush toilet 10 may be mounted in a variety of ways, either to a floor or a wall. To facilitate installation on a wall, the flush toilet 10 may include one or more mounting holes that are configured to facilitate mounting to the wall such as using one or more fasteners and/or threaded stud bolts.

It will be apparent that various other modifications and adaptations of the invention will be apparent to the person skilled in the art after reading the foregoing disclosure without departing from the spirit and scope of the invention. It is intended that all such modifications and adaptations come within the scope of the appended claims.

Further, it is to be appreciated that features from various embodiment(s), may be combined to form one or more additional embodiments. Examples

Non-limiting examples of the present disclosure will be further described, which should not be construed as in any way limiting the scope of the disclosure. Example 1

A flush toilet in accordance with an embodiment of the present invention was manufactured and tested with reference to standards known in the art, in particular, the Singapore Standard SS 574: Part 1 : 2012, which is suitable for dual flush low capacity water closets (WC) up to 4.5/3.0L capacity. The flush toilet is capable of having a full flush water volume of 3.5L and a reduced flush water volume of 2.5L per flush cycle.

As indicated in Table 1 which shows the test results of a flush toilet having a flush volume of 3.5L (full flush test), up to 20 pieces of toilet paper can be flushed using as little as 3.5L of water. This surpasses the 12 pieces of toilet paper, as required by SS 574: Part 1 : 2012, as well as the other standard tests such as the ball test, towel test and sawdust test. When a reduced flush test using a flush volume of 2.5L was carried out, 4 joined pieces of toilet paper could be effectively flushed, as required by SS 574: Part 1 : 2012. Furthermore, the flush toilet was also able to pass the dye test at the reduced flush volume of 2.5L. Accordingly, the results show that the flush toilet of the present invention can achieve efficient waste removal using a relatively small amount of water.

Example 2

The flush toilet from Example 1 was also compared with a conventional box rim wash closet (WC). Advantageously, the noise level produced by the flush toilet of the present invention was lower than that of a conventional box rim WC, as indicated by the lower peak values obtained in all three tests conducted, with the average peak value being 77 dB. In comparison, the noise level of a conventional box rim WC was higher (average peak value of 80 dB). Accordingly, in addition to being able to efficiently remove waste using a relatively small volume of water, the flush toilet of the present invention is relatively silent.

Note: The ambient noise level for the above-mentioned tests is about 45 dB.

Claims

1. A toilet bowl comprising: at least one fluid outlet disposed on an inner surface of the toilet bowl, the fluid outlet arranged to output a flush fluid at a predetermined flow rate; and a fluid guide arranged in fluid communication with the fluid outlet to receive the flush fluid, the fluid guide arranged around a portion of the inner surface of the toilet bowl to direct flush fluid around an upper inner surface of the toilet bowl.

2. The toilet bowl according to claim 1 , further comprising a rim having a first flange protruding from the inner surface of the toilet bowl to form part of the fluid guide.

3. The toilet bowl according to claim 2, wherein the fluid guide comprises a second flange protruding from the inner surface of the toilet bowl, wherein the first flange and the second flange form a channel for the flush fluid to flow therebetween.

4. The toilet bowl according to any one of claims 1 to 3, wherein the thickness of the fluid guide changes across the upper inner surface of the toilet bowl.

5. The toilet bowl according to claim 2, wherein the thickness of the first flange changes across the upper inner surface of the toilet bowl.

6. The toilet bowl according to any one of claims 2 to 5, wherein the first flange comprises an edge inclined towards the second flange.

7. The toilet bowl according to claim 6, wherein the portion of the second flange adjacent to the edge has a smaller protrusion relative to the other portions of the second flange.

8. The toilet bowl according to any one of claims 3 to 7, wherein the second flange comprises a rounded edge.

9. The toilet bowl according to any one of the preceding claims, wherein the at least one fluid outlet comprises a main fluid outlet and a plurality of small fluid outlets.

10. The toilet bowl according to any one of the preceding claims, wherein the fluid guide extends more than half the parameter of the toilet bowl.

1 1 . The toilet bowl according to claim 10, wherein the parameter is a circumference of the toilet bowl.

12. The toilet bowl according to claim 9, wherein the main fluid outlet comprises a width of about 35 mm to about 40 mm.

13. The toilet bowl according to claim 12, wherein the main fluid outlet has a length of about 40 mm to about 45 mm.

14. The toilet bowl according to claim 9, wherein the main fluid outlet is off-centre and disposed on the upper inner surface of the toilet bowl.

15. The toilet bowl according to claim 9, wherein the plurality of small fluid outlets are located on a back rim disposed on a rearmost portion of the toilet bowl.

16. The toilet bowl according to claim 9, wherein the plurality of small fluid outlets are angled such that flush fluid from the small fluid outlets move in the same direction as the flush fluid from the main fluid outlet.

17. The toilet bowl according to claim 9, wherein the main fluid outlet is located at about 45 degrees away from the centre of the toilet bowl.

18. A flush toilet comprising a toilet bowl according to any one of claims 1 to 17.