The present invention relates to a toilet assembly. In particular the invention relates to a portable toilet made up of modular moulded plastic components.

However, the invention is not restricted to portable toilets and may be used in any structure without fixed plumbing where a chemical toilet is required e.g. a caravan or portable building.

Portable toilets are usually assembled from a number of separately constructed parts. These parts may include a waste tank incorporating a toilet bowl, a water tank for flushing together with a separate floor, walls and a roof. Generally, the water tank is secured to the walls by appropriate fasteners. Plumbing fittings are also included to connect the water tank to the toilet bowl. If the toilet includes a hand basin then plumbing fittings must also be included to connect the water tank with the hand basin and the hand basin to the waste tank. In a structure such as a mobile toilet where costs are kept to a minimum, such plumbing fittings may be left exposed and therefore may appear unsightly. Additionally, in a compact structure such as a mobile toilet, there may be limited space for such plumbing fittings.

In one known construction of portable toilets, the water tank is secured to one or more of the walls and water is supplied to the toilet bowl by gravity. The location of the water tank on the walls may render the portable toilet unstable during transportation, especially when the water tank is full. A full water tank will also place a heavy burden on the walls. Furthermore, where a hand basin is gravity fed from the water tank, the location of the water tank above the hand basin will be further dictated by the requirement for the hand basin to be located at a user friendly height.

It is therefore an object of the present invention to provide a toilet assembly which overcomes or ameliorates the abovementioned disadvantages.

In accordance with the first aspect of the present invention there is disclosed an assembly for a mobile toilet comprising a first fluid tank unit, a second fluid tank unit and a coupling to secure the first tank unit and the second tank unit together. The coupling has a hole extending therethrough to allow the transfer of

fluid between the tank units.

In a preferred form of the invention, the tank units may have one or more mating projections and recesses to install one of the tank units above the other tank unit. Preferably there are a pair of spaced complementary projections and recesses enabling one of the tank units to be supported in a stable manner above the other tank unit. In a most preferred form of the invention, a coupling extends between each mating projection and recess.

Preferably, the coupling is in the form of a fastening assembly securely attaching the first tank unit to the second tank unit. The coupling may be in the form of a threaded fastening assembly. In a most preferred form, the coupling comprises a threaded aperture located on one of the tank units and a flanged tubular fastener extending through an aperture in the other tank unit to fasten with the threaded aperture. The flanged tubular fastener is most preferably in the form of a bolt having a bore extending through the axis of the bolt. In the preferred embodiment of the invention, the first tank unit is installed above the second tank unit, the first tank unit including a fresh water tank and the second tank unit including a waste tank and a toilet bowl. The fresh water tank may therefore be connected by a hose through one of the couplings to the toilet bowl obviating the requirement for exposed hoses or pipes. In accordance with a second aspect of the present invention there is disclosed a toilet assembly including a toilet bowl or like receptacle, a water supply and a pumping means for pumping water to the toilet bowl for flushing and to an outlet for hand washing. Actuation of the pumping means causes water to be simultaneously pumped to the toilet bowl and to the outlet for hand washing. In a refined form of the above defined invention, there may be an auxiliary tank to store water for hand washing. Water may be pumped to the auxiliary tank so that water may be dispensed from the outlet of the auxiliary tank as needed.

In a most preferred form of the invention, the water supply may be included within a first tank unit and the toilet bowl may be included in a second waste tank unit. The tank units are then secured together by one or more couplings as defined in the first aspect of the present invention, such that water may flow from the first

tank unit to the toilet bowl in the second waste tank unit through one of such couplings. An outlet for hand washing may also be incorporated into the first tank unit. Thereby, waste water from hand washing can flow to the waste tank through one of the couplings. In accordance with a third aspect of the present invention there is disclosed a toilet assembly including a waste tank wherein the base wall of the waste tank slopes towards a central gutter extending across the waste tank such that in use, solids in the tanks slide towards the central gutter.

A further gutter, extending transversely to the first mentioned gutter may also be provided, the intersection of the gutters defining in use, the lowest point in the base of the waste tank.

In accordance with a fourth aspect of the present invention there is disclosed a toilet assembly including a waste tank having a base wall and an upper wall, the upper wall defining a floor of the toilet assembly, wherein projections extend upwardly from the base wall to support the floor of the toilet assembly.

In a preferred form, the projections are in the form of a plurality of spaced cylinders. The cylinders may be integrally moulded with the base wall of the waste tank. Suitably, the projections abut the floor of the toilet assembly or are spaced slightly therefrom. In order that the invention is more readily understood, a particular embodiment thereof will now be described by way of example with reference to the accompanying drawings wherein:

Figure 1 is a perspective view of the toilet assembly in accordance with a preferred embodiment of the present invention; Figure 2 is a plan view of the toilet assembly of Figure 1;

Figure 3 is a perspective view of a portion of the toilet assembly of Figure

1;

Figure 4 is a perspective view of a portion of the toilet assembly of Figure

X; , Figure 5 is an exploded perspective view of the toilet assembly of Figure 1;

Figure 6 is a front elevation of the toilet assembly of Figure 1;

Figure 7 is a side sectional view of the toilet assembly of Figure 1; and Figure 7A is a part sectional view through A- A of Figure 5. Figure 1 illustrates a toilet assembly 11 comprised of a waste tank unit 12 and a flush tank unit 13. The waste tank unit 12 and the flush tank unit 13 are separately moulded from plastic material and assembled together in a manner which will be described more fully in connection with Figures 7 and 7A. Figures 3 and 4 show the waste tank unit 12 and the flush tank unit 13 separately.

The waste tank unit 12 is a moulded tank comprised of a lower base portion 20 having a lower wall 21 defining a base of the toilet assembly and an upper substantially horizontal wall 22 defining a floor of the toilet assembly. The waste tank unit 12 also comprises upper tank portions 24, 25 and 26 extending around the edge of the floor 22 on three sides thereof. The upper portions 24, 25 and 26 are in direct communication with the lower base portion 20 resulting in a large capacity waste tank unit 12. As discussed, the upper portions 24, 25 and 26 extend around only three sides of the floor 22, thereby defining an entrance 27 to provide access for a user to enter the toilet assembly 11. The floor 22 may slope downwardly towards the entrance 27 to enable any excess water on the floor 22 to flow towards the entrance 27 and out of the toilet assembly 11. As shown in Figure 2, the waste tank unit 12 is also provided with supports for the floor 22. The supports are in the form a plurality of spaced cylinders 31. The cylinders 31 are integrally formed in the lower wall 21 of the waste tank unit and extend upwardly towards the upper wall 22 which defines the floor of the toilet assembly 11. The cylinders 31 abut against the floor 22 or are slightly spaced therefrom as the floor 22 being constructed of plastics material may have some capacity to bow under the weight a person standing on the floor 22.

Referring back to Figure 1, a horizontal step 28 is shown circumscribing the waste tank unit 12. The step 28 is located between the lower base portion 20 and the upper portions 24, 25 and 26 of the waste tank unit 12. The horizontal step 28 provides support for the side walls (not shown) which once assembled extend around three sides of the waste tank unit 12 adjacent the upper portions 24, 25 and

26. The step 28 also provides support for an entrance door (not shown) to the toilet assembly 11, the door extending across the entrance 27. A roof structure (not shown) is also supported by the walls. The side walls and the door are thus closely fitted around the toilet assembly 11 to form a compact assembly. Captive nuts (not shown) are also integrally formed in the walls of the waste tank unit 12 so that the walls, mounted on the step 28 can be bolted directly to the waste tank unit 12. This results in a toilet assembly which is easy to assemble and strong.

In one corner of the waste tank unit 12 opposite the entrance 27 is provided a seat support portion 23 on which is mounted a seat and bowl assembly 29. The seat and bowl assembly 29 will be discussed in more detail in connection with Figure 5.

The flush tank unit 13 is mounted on the opposite side of the toilet assembly 11 to the seat support portion 23. The flush tank unit 13 overlies the upper portion 26 of the waste tank unit 12 and the upright walls of the flush tank unit 13 are substantially flush with the upper walls of the upper portion 26.

Figure 3 shows in greater detail the support mountings for the flush tank unit 13 above the upper portion 26 of the waste tank unit 12. It will be appreciated that when the flush tank unit 13 is filled with water, the flush tank unit 13 will have considerable mass. Since the toilet assembly 11 is adapted to be portable, the flush tank unit 13 must be securely mounted to the waste tank unit 12. The mounting is in the form of two spaced upwardly extending projections 32, located at either end of the upper portion 26. Each projection 32 has an orifice 33 extending therethrough which leads to the waste tank unit 12. The orifices 33 are both threaded, the reason for which will be explained more fully in connection with Figures 7 and 7A.

Figure 4 separately illustrates the flush tank unit 13 having complimentary recesses 41 located at either end of the unit 13. The flush tank unit 13 also includes a pump having lever 51, hand wash basin 44 and auxiliary tank 43. The auxiliary tank 43 has an outlet 45 to provide water to the hand wash basin 44 for the purpose of washing hands. The outlet 45 preferably has a spring valve permitting flow of water therethrough only when the valve lever is depressed. This

ensures minimum wastage of water. The bulk of the waste tank unit 13 is a main water tank 42. An access cover 53 also provides a large access aperture to the main water tank 42 to enable thorough cleaning.

The pump which is actuated by movement of the lever 51 serves a dual purpose to pump water from the main water tank 42 to the seat and bowl assembly 29 to enable flushing thereof and to pump water from the main water tank 42 into the auxiliary tank 43. The provision of a single pump serving two purposes reduces the component cost for the toilet assembly 11 as well as simplifying the design and assembly operation. Figure 5 more clearly illustrates the individual components which are assembled to form the toilet assembly 11. Also shown in Figure 5 is a skid assembly 71 on which the base 21 of the toilet assembly 11 is mounted. The skid assembly 71 enables the toilet assembly 11 to be pulled along the ground to a desired site. The four corners of the skid assembly 71 are also provided with connecting loops 70. A wire cable or chain (not shown) is connected to each of these connecting loops 70. Each chain or cable 70 extends upwardly from the connecting loop 70 into the interior of the toilet assembly 11. Each cable or chain extends alongside the internal corners of the toilet assembly 11 and up through the roof of the assembly 11 where all of the chains or cables are combined into a single lifting loop or hook. This lifting loop or hook may then be connected to a crane or hoist to transfer the toilet assembly 11 to a preferred location on a site or on/ off a truck. Since the chains or cables extend right through to the skid assembly 71 from the base of the assembly 11, the assembly 11 is lifted from the base to ensure that the assembly may be safely and securely lifted. Referring still to Figure 5, the components of the seat and bowl assembly 29 can be more clearly seen. At the top of the seat support portion 23, is a large opening 69 around which is located a seat assembly mount 66. The mount 66 provides a base for mounting the seat and bowl assembly 29 while maintaining a large access opening 69 to the interior of the waste tank unit 12. The toilet seat and bowl assembly 29 comprises a toilet seat mount 63 which is hinged to the seat assembly mount 66. A standard toilet seat 62 is then mounted on top of the toilet

seat mount 63 and a toilet bowl 64 is formed integral on the underside of the toilet seat mount 63. The toilet bowl 64 has a lower aperture adjacent which a stainless steel flapper 65 is hinged. The flapper 65 is in the form of a flap and a counterweight. The flap extends across the lower aperture of the toilet bowl 64 and includes a peripheral rim to abut lower regions of the toilet bowl 64 to retain in the flap a volume of water from the flush. This provides a water seal between the toilet bowl 64 and the waste tank unit 12 to prevent egress of odors up through the toilet bowl 64. The counterbalance of the flapper 65 allows solids to pass through to the waste tank unit 12 but ensures that otherwise that the flapper 65 is closed. It will be appreciated that having the toilet seat mount 63 and toilet bowl 64 hingedly mounted to the waste tank unit 12, enables the toilet seat mount 63, toilet bowl 64, and toilet seat 62 to be hinged away from the large access hole 69. The provision of a large access hole 69 assists with thorough cleaning of the waste tank unit 12 as will be discussed in connection with Figures 6 and 7. Adjacent the seat assembly mount 66 is a smaller hole communicating with the interior of the waste tank unit 12. A release pipe 67 extends out of the hole and up through the roof of the toilet assembly 11 to allow odours to escape from the waste tank unit 12 and into the outside air.

Figures 6 and 7 more clearly illustrate the shape of the lower wall 21 defining the base of the waste tank unit 12. The lower wall 21 is provided with a first gutter 74 extending centrally across the waste tank unit 12 from a location adjacent the entrance 27 to the rear of the waste tank unit 12. A second gutter 73 extends across the rear of the waste tank unit 12 substantially underneath the upper portion 25 of the waste tank unit 12. The lower wall 21 also slopes downwardly towards the first gutter 74 and the second gutter 73. The first gutter 74 and second gutter 73 converge to form a central sump located substantially underneath the seat and bowl assembly 29. The lower wall 21 of the waste tank unit 12 is constructed of a moulded plastic material which has the beneficial property of a smooth surface to which solids will not stick. Thus any solids will slide along the lower wall 21 to either the first gutter 74 or the second gutter 73 or the central sump. Since the solids will be pooled into a small region when the toilet assembly 11 is only

operating at minimum capacity, the quantity of chemicals required to decompose the solids is reduced. The non-adhering nature of the plastics material also simplifies the cleaning process.

As shown in Figure 7, a gate valve 72 is provided adjacent the second gutter 73 to allow waste to be pumped out of the waste tank unit 12. It will be appreciated that the first and second gutters 73, 74 assist in emptying the tank as solids tend to flow to a location adjacent the gate valve 72. A water hose may also be placed through the large access opening 69 to assist with thorough cleaning of the waste tank unit 12. Alternatively, cleaning of the waste tank unit can be conducted by pumping the waste out through the large access opening 69. The large access opening 69 also enables visual inspection of the interior of the waste tank unit 12, ensuring more efficient and effective cleaning.

Figures 7 and 7A more clearly show the nature of the coupling between the waste tank unit 12 and the flush tank unit 13. As shown in Figure 7A, the projection 32 extending from the waste tank unit 12 is received within complimentary recess 41 provided on the underside of flush tank unit 13. As previously discussed, the projection 32 is provided with a threaded orifice 33. An upper wall of the complimentary recess 41 also has an aperture corresponding to the aperture 33, through which a tubular threaded fastener 80 extends for threaded engagement in threaded aperture 33. This ensures a strong coupling between the flush tank unit 13 and the waste tank unit 12. The fact that fastener 80 is tubular also provides a fluid coupling between the flush tank unit 13 and the waste tank unit 12. A fluid tight seal may also be achieved between the projection 32 and the recess 41, preventing leakage of fluid to the exterior of the tank units 12, 13. As shown in Figure 7, a pump 47 is used to draw water from the base of the main water tank 42 through an inlet pipe 48. A flush pipe 49 carries water from the pump 47 through the hollow fastener 80 and threaded aperture 33 to the seat and bowl assembly 29. Therefore, actuation of the lever 51 provides water for flushing the toilet bowl 64. A wash pipe 50 also connects the pump 47 to the auxiliary tank 43. The auxiliary tank provides water for hand washing via the tap 45. The wash basin 44 is connected to the waste tank unit 12 via a basin outlet

pipe 52 which extends through the hollow nut 80 and threaded aperture 33 so that water may flow from the wash basin 44 through to the Waste tank unit 12. In an alternative arrangement, water may not flow directly from the hand wash basin 44 to the waste tank unit 12 but to a holding tank. Water from the holding tank may then be used for flushing purposes.

A notable feature of the present invention is that the pump 47 is dual purpose simultaneously pumping water to the seat and bowl assembly 29 for flushing and to the auxiliary tank 43 for the purpose of hand washing. The auxiliary tank 43 may also be provided with an overflow valve to return water to the main water tank 42 in the event that the auxiliary tank 43 is completely filled.

A further advantageous feature of the toilet assembly 11 of the present invention is that it can be adapted to form a "straight drop" toilet without substantial alteration by merely removing the flush tank unit 13. The present invention also provides a toilet assembly with few components to simplify construction.

Since modifications within the spirit and scope of the invention may be readily effected by persons skilled in the art, it is to be understood that the invention is not limited to the particular embodiment described, by way of example, hereinabove.