IE20030086A1 - A mobile cabin with toilet facilities - Google Patents

Abstract

The invention concerns a mobile cabin comprising at least one toilet compartment containing a toiler (w/c) and a flushing system for the toilet including a water cistern, a waste outlet from the toilet having a water trap, the waste outlet communicating with a waste storage tank located below the level of the waste outlet, and wherein non-return valve means are provided at the inlet to the waste storage tank to prevent backward surging of waste from the tank into the toilet on forward movement of the mobile cabin. The toilet and waste trap are positioned transversely of the longitudinal axis of the mobile cabin whereby the water trap is maintained during travelling of the mobile cabin. The waste storage tank is comprised of a main storage tank and an associated sump, the floor of the sump being positioned at a lower level than the floor of the main tank, and a waste outlet pipe communicates with the sump and is adapted for connection to a hose to facilitate emptying of the sewage tank. Suitably the cabin has a canteen compartment including a table and seating, cooking facilities, and at least one toilet compartment containing the toilet and cistern, and wherein at least one water tank is provided to supply water to the canteen and to the toilet cistern. <Figure 1>

Description

Technical Field of the Invention The invention relates to a mobile site cabin containing a toilet unit having a flush toilet, a water storage tank, and a waste/sewage storage tank. The invention is particularly concerned with a mobile site cabin which may be used as a welfare unit to accommodate road workers and other outdoor workers.

Background to the Invention Due to increased health and safety regulations better quality accommodation is required for outdoor workers to provide improved shelter, a heated environment and proper toilet, washing and eating facilities. A mobile site cabin to be used for such purposes needs to overcome the practical problem that usually there are no services, such as septic tanks, water supply and power supply, where the mobile unit would be in use. It is known to have mobile accommodation such as motor homes, caravans or campers. Such mobile accommodation tends to be provided with chemical toilets which are not satisfactory for use with mobile site cabins. There are a number of problems associated with the use of conventional flush toilets in mobile accommodation. If the sewage is retained in a holding tank there is a tendency for the liquid sewage to surge back into the toilet bowl on movement of the mobile accommodation. Secondly, conventional flush toilets have a water seal in the toilet bowl and this seal may be broken during travelling because the water in the toilet bowl surges forwardly and backwardly with movement of the vehicle which results in the water being siphoned out of the water trap. There is also a problem associated with the storage and venting of the sewage and the emptying of the sewage into a suitable sewer system. Also, there is a need to provide a sufficient volume of water to enable flushing of the toilet.

Object of the Invention It is an object of the invention to overcome the above problems and to provide a mobile cabin having a toilet bowl and cistern together with a sewage storage tank.

Summary of the Invention Accordingly, the invention provides a mobile cabin comprising at least one toilet compartment containing a toilet (w/c) and a flushing system for the toilet including a water cistern, a waste outlet from the toilet having a water trap, the waste outlet communicating with a waste storage tank located below the level of the waste outlet, and wherein non-return valve means are provided at an inlet to the waste storage tank to prevent surging of waste from the tank into the toilet on acceleration or deceleration of the mobile cabin.

In accordance with another aspect of the invention, the toilet and water trap are positioned transversely of the longitudinal axis of the mobile cabin whereby the water trap is maintained during travelling of the mobile cabin.

Preferably, the waste storage tank is comprised of a main storage tank and an associated sump, the floor of the sump being positioned at a lower level than the floor of the main tank, and a waste outlet pipe communicates with the sump and is adapted for connection to a hose to facilitate emptying of the sewage tank.

In accordance with one embodiment, the mobile cabin has at least one canteen compartment including a table and seating, cooking facilities, and at least one toilet compartment containing the toilet and cistern, and wherein at least two water tanks are provided to supply water to the canteen, and to the toilet cistern, respectively.

The water supply tanks and the waste storage tank have a capacity such that the mobile cabin need only be serviced (i.e. water tanks filled, and waste tank emptied) approximately once per week in normal use.

Brief Description of the Drawings One embodiment of the invention is hereinafter described with reference to the accompanying drawings wherein: Figure 1 is a front perspective view of a mobile site cabin of the invention; Figure 2 is a rear view of the cabin of Figure 1; Figure 3 is a plan view of the mobile site cabin of Figure 1; Figure 4 is a perspective view of a toilet compartment; Figure 5 is a diagrammatic plan view of the toilet (w/c) and sewage/waste tank; Figure 6 is a side view of the sewage/waste tank and non-return valve; Figure 7 is a part-sectional perspective view, to an enlarged scale, of the sewage/waste tank and the non-return valve of Figure 6; Figure 8 shows in detail of a sewage outlet pipe with flexible hose disconnected; and Figure 9 shows a detail of a sewage outlet pipe with flexible hose connected.

Detailed Description of the Drawings Referring to Figures 1 to 3 of the drawings, this shows one embodiment of a mobile site cabin in accordance with the invention. This particular embodiment is suitable for use as a welfare unit to accommodate road workers and other outdoor workers.

The mobile cabin comprises a steel chassis 1 which is mounted on two pairs of road wheels 2. The chassis has a tow hitch 21 at the front thereof by means of which the mobile site cabin may be towed behind a vehicle. The cabin 3 is built on top of the chassis 1, and comprises outer walls 4, suitably made from sheet metal, plastics, glass fibre, wood or other suitable material.

In the particular embodiment shown, the cabin is comprised of three compartments. The cabin includes a canteen compartment 5 at the front of the unit, which is separated by a bulkhead 6 from a toilet compartment 7, and a store compartment 8 located to the rear of the unit. The toilet compartment 7 is separated from the store 8 by a partition 9.

As shown in Figure 1 and Figure 3, a door 10 is provided in one side wall of the cabin and leads to the canteen compartment 5. The canteen compartment includes a table 11, seating 12, and a heater 13. The front of the compartment is provided with a worktop 14, into which is built a sink 15 and a cooking appliance 16. Suitably the cooking appliance includes two gas burners, which may be fuelled by means of gas cylinders. The gas cylinders are preferably located in a small compartment in the front of the cabin through which access is obtained by means of a door 17 opening from the outside of the cabin (see Fig. 1). The canteen compartment is provided with a window 18, suitably located in the wall opposite the door 10. Preferably, the window 18 is provided with sliding steel security shutters 48.

The rear wall of the cabin contains doors 19, 20 leading to the toilet compartment, and to the store compartment, receptively. All of the compartments are provided with suitable air vents 22.

The toilet unit comprises a flushing toilet (w/c) 23. This comprises a toilet bowl 24 having a water cistern 25 mounted above the toilet bowl for flushing of the bowl in well known manner. Alternatively, a water saving toilet may be used.

The w/c 23 is fitted with a conventional integral waste outlet 27 having an “sbend” (or double u-bend) which provides a water seal.

As shown in Figures 4 to 6, the waste outlet 27 connects into a waste pipe 28, which suitably is a 90° multiwick pipe. The pipe 28 is fitted with a bent portion 29 (suitably a 90° multiwick) which leads into a waste inlet 30 of a sump compartment 32 of a sewage/waste tank 31.

The waste tank 31 is a substantially flat rectangular tank which is adapted to be mounted on the chassis below the floor of the canteen compartment 5. The waste tank is comprised of two tanks namely a main tank 31 which is of rectangular box shape and a smaller, sump tank 32. Suitably, the sump 32 is of rectangular shape and communicates with the main tank 31 by means of an open channel 34 which extends along the length of the sump 32 at a top portion thereof. The floor of the sump 32 is located below the level of the floor of the main tank 31 such that waste solids will tend to accumulate in the sump 32. The provision of the sump 32 also facilitates the complete draining of the main tank 31 when the tank is emptied as described below.

If the mobile cabin is towed while the waste tank is full or partially full, there is a tendency for liquid in the waste tank to surge rearwardly on forward motion (acceleration) of the mobile unit which could cause back-flow up into the toilet bowl 24. In the event that the toilet 23 is located forwardly of the waste tank 31, there would be a forward surge of liquid in the tank on deceleration of the mobile cabin. Both of the above are prevented in accordance with invention by the provision of a non-return valve 35 at the lower end of the waste inlet 30 where it enters the top of the sump 32.

The non-return valve 35 is shown most clearly in Figures 6 and 7. It comprises a flap 36, suitably made of metal, which is hinged at its top edge to a hinge 37. As shown in Figure 7, the hinge 37 is secured transversely of a box section 38 which houses the waste inlet pipe 30. The waste inlet pipe 30, where it enters the sump 32, is inclined downwardly, and rearwardly of the direction of motion of the mobile cabin. When the mobile cabin is stationery, the flap 36 hangs substantially vertically from the hinge 37.

In this position, a stop 39 on the front face of the flap 36 abuts against the wall of the sump 32. In the event of liquid waste in tank 31 surging rearwardly in the direction of the arrows 40 shown in Figure 6, the pressure of liquid pushes back on the flap 36 and the flap is forced against the inclined opening of the waste inlet pipe 30 to seal the pipe and to prevent back-flow of the liquid into the pipes 29 and 28 and into the toilet bowl 24.

In accordance with another aspect of the invention, movement of water in the water trap of the toilet 23, on travelling of the mobile unit, is prevented by mounting the toilet 23 and toilet bowl 24 transversely of the direction of travel of the mobile unit. In other words, the direction of flow of liquid through the integral waste outlet 27 is substantially at right angles to the longitudinal axis of the mobile site cabin. Thus, movement of the mobile cabin in the longitudinal direction (as shown by the arrow in Figure 5) does not cause the water in the water trap of the toilet 23 to surge backwardly and forwardly, as would happen if the bowl 24 was positioned longitudinally of the mobile cabin. Accordingly, siphoning of the water in the water trap is prevented.

As shown in Figures 4, 5 and 6, waste pipe 28 connects with a vent pipe 33 which rises vertically of the inner wall of the toilet compartment, and vents to atmosphere at the roof of the unit. The vent pipe 33 vents both the waste storage tank 31 and the toilet 23. .

The sump compartment 32 is provided with a waste outlet pipe 41. The outlet is positioned adjacent the bottom of the sump 32. The waste outlet pipe 41 is provided with a wheel valve 42. As shown in Figures 8 and 9 the end of the outlet pipe 41 is provided with a connector fitting 43. The connector fitting 43 is adapted to mate with a hose connection fitting 44 on the end of a flexible waste disposal hose 45. The connector fittings 43 and 44 form a water tight connection between the hose 45 and the outlet pipe 41 to enable easy emptying of the contents of the sewage/waste tank 31 and sump 32 into a sewer or treatment plant. A storage compartment 46 for the hose 45 is provided below the chassis 1 (see Fig. 1).

Although not shown in the drawings, the mobile site cabin is provided with two integral water storage tanks which suitably are located beneath the bench seating 12 in the canteen compartment 5 and which are interconnected. A pump is provided in the storage compartment 8, powered by a 12 volt battery and is adapted to pump water from the tanks for washing and cooking purposes, and to supply the cistern 25 for flushing of the toilet 23. Suitably, the tanks are steel tanks having a capacity of 250 litres each, that is a total capacity of 500 litres. The tanks may be provided with a water level gauge and a hose reel for filling of the tanks. The capacity of the tanks is sufficient for one weeks normal operation of the mobile unit. The sewage/waste tank 31 is prevented from over filling by designing the capacity of the water tank so that it is the same or somewhat it ΰ smaller than the capacity of the sewage holding tank. The water level gauge includes a low level alarm on the water tank which indicates that the toilet should not be used after the level of water in the tank has dropped to a pre-determined minimum.

. The capacity of the water storage tanks and the sewage/waste tank are such that the mobile unit needs only to be serviced approximately once per week. At that time, the sewage tanks are emptied and the water tanks are filled. This is done in the same operation to ensure that the water tanks are filled when the sewage/waste tank is empty.

Suitably, the outer skin of the walls 4 of the mobile cabin manufactured from 1.5mm galvanised sheeting. An internal skin of the walls comprises a composite panel which has a plastics (e.g. PVC) coated internal finish, and suitably has a thickness of 45mm. The window 18 suitably is manufactured in aluminium whereas the sliding security shutter 48 is suitably manufactured from steel.

The sewage and waste tank 31 and the water tanks are suitably manufactured from galvanised steel sheeting. The capacity of the sewage/waste storage tank 31 may be in the range of 100 litres to 1000 litres, depending upon the size of the mobile cabin and the number of people it is intended to accommodate. For example, a 1000 litre sewage tank will accommodate 12 people for a period of one week, whereas a 500 litre tank will accommodate six people for one week.

The invention is not limited to the particular embodiment of non-return valve illustrated in the drawings and described above. It would be appreciated to one skilled in the art that various types of non-return mechanisms may be utilised, including mechanically operated, electrically operated, hydraulically operated and pneumatically operated valves to replace the flap 36 shown in the drawings. However, the particular embodiment shown in the drawings has the advantage that it is simple to fit and operate, and is reliable in use.

In the embodiment shown in the drawings, the mobile cabin is in the form of a trailer to be towed behind a vehicle. Alternatively, the mobile cabin may be self7 propelled. All electrical equipment within the mobile cabin may be powered by means of a 12 volt battery power supply, but a generator could also be used.

From the foregoing, it will be apparent that numerous modifications and 5 variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It will be appreciated that the present disclosure is intended to set forth exemplifications of the invention which are not intended to limit the invention to the specific embodiments illustrated. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims.

The words “comprises/comprising” and the words “having/including” when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

Claims (7)

Claims

1. A mobile cabin comprising at least one toilet compartment containing a toilet (w/c) and a flushing system for the toilet including a water cistern, a waste outlet from the toilet having a water trap, the waste outlet communicating with a waste storage tank located below the level of the waste outlet, and wherein non-return valve means are provided at an inlet to the waste storage tank to prevent surging of waste from the tank into the toilet on acceleration or deceleration of the mobile cabin.

2. A mobile as claimed in Claim 1 wherein the toilet and water trap are positioned transversely of the longitudinal axis of the mobile cabin whereby the water trap is maintained during travelling of the mobile cabin.

3. A mobile cabin as claimed in any of the preceding claims, wherein the waste storage tank is comprised of a main storage tank and an associated sump, the floor of the sump being positioned at a lower level than the floor of the main tank, and a waste outlet pipe communicates with the sump and is adapted for connection to a hose to facilitate emptying of the sewage tank.

4. A mobile cabin as claimed in any of the preceding claims comprising at least one canteen compartment including a table and seating, cooking facilities, and at least one toilet compartment containing the toilet and cistern, and wherein at least one, but preferably two, water tanks are provided to supply water to the canteen and to the toilet cistern.

5. A mobile cabin as claimed in any of the preceding claims wherein the inlet to the waste storage tank comprises a waste inlet pipe and the non-return valve comprises a flap which is hingedly mounted and is moveable from an open position to a closed position where it seals the inlet end of the waste inlet pipe.

6. A mobile cabin as claimed in claim 5, wherein the inlet end of the waste inlet pipe has an opening, the plane of which is inclined downwardly, and opens rearwardly of IE 0 J Ο Ο 8 β the direction of motion of the mobile cabin, and the valve flap is moveable from an open, substantially vertical position, under pressure of liquid surges, to a closed position, where it is forced against the inclined opening of the waste inlet pipe to seal the pipe opening whereby back-flow of the liquid into the pipe is prevented.

7. A mobile cabin substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.