Toilet system with reduced or eliminated flushing requirement, especially for transportation vehicles

Abstract

A toilet system, especially for passenger transport vehicles, includes a toilet bowl connected via a suction valve and a waste collection pipe to a waste collection tank. Waste-contacting surfaces of the toilet system that come into contact with urine and fecal waste are coated with an adhesion-inhibiting or adhesion-reducing nanocoating. Thereby, the adhesion of waste to the toilet bowl and other components is significantly reduced, and the total flushing water demand can be substantially reduced or, preferably completely eliminated. An airflow flowing into the toilet bowl, induced by the vacuum suction through the suction valve, is sufficient to "flush" the waste material from the nanocoated waste-contacting surfaces. The toilet system provides a substantial reduction in the total system weight and in the required quantity of flushing water that must be carried in the vehicle, and thus makes the toilet system particularly applicable for passenger transport vehicles such as aircraft.

Description

[0001] This application is a Continuation-in-Part under 35 U.S.C. .sctn.120 of our prior co-pending U.S. patent application Ser. No. 09 / 603,854, filed on Jun. 26, 2000.PRIORITY CLAIM[0002] This application claims the priority under 35 U.S.C. .sctn.119 of German Patent Application 199 28 894.1, filed on Jun. 24, 1999.[0003] The invention relates to a toilet system, especially for transportation vehicles, including at least one toilet bowl connected to a waste collection tank by a suction valve.BACKGROUND INFORMATION[0004] Transportation vehicles, particularly aircraft, have only a limited capacity for carrying flushing liquid for rinsing or flushing toilets and waste water. For this reason, transportation vehicles often use toilet systems in which the toilet bowl is connected to a waste collection tank by a suction valve, and particularly toilet systems that are constructed as vacuum systems. Conventional toilet systems use a flushing liquid to flush the toilet bowl, whereby the flus...

AI Technical Summary

Benefits of technology

[0011] The above objects have been achieved in a toilet system according to the invention in which the toilet bowl is connected by a suction valve to a waste collection tank, and in which at least some of the system components that come into contact with waste material are provided with a nanocoating. Particularly at least a portion of the inner bowl surface of the toilet bowl itself is provided with a thin film coating deposited by nanotechnology processes. The nanocoating is provided at least on the entirety of the waste-contacting inner surface area of the toilet bowl, preferably the nanocoating may cover a whole inner surface of the toilet bowl. Such a nanocoating significantly reduces or eliminates the adhesion of fecal residue and other wastes on the waste-contacting surfaces of the toilet bowl, the waste line, the flush valve, and / or the waste tank, and therefore reduces or eliminates the demand for flushing liquid. The nanocoating also avoids the need to provide wrappers or the like for encapsulating the fecal waste in the toilet bowl, as in some prior art systems. These features in turn simplify and reduce the weight of the overall toilet system.

[0012] The toilet system according to the invention is particularly advantageous because it provides a substantial reduction in weight relative to the conventional systems. This is especially important for the use of such toilet systems in aircraft. The overall amount of flush water or liquid required for rinsing or flushing the toilet can be substantially reduced or can even be completely eliminated. The weight that is saved due to the elimination or reduction of flush water can be used, for example, to allow increasing the seating capacity in the transportation vehicle.

[0013] The invention further provides a method for manufacturing a toilet system according to the invention. The surface of the toilet bowl to be coated with the nanocoating can be pretreated with grinding, polishing and surface cleaning operations. The nanocoating can be applied by means of cathodic sputtering or gas phase deposition processes such as chemical vapor deposition or physical vapor deposition processes. Waste contamination and adhesion of particles can be avoided particularly by applying the nanocoating to the waste-contacting surface portion of the toilet bowl that comes into contact with waste materials or is exposed to a passenger.

[0014] In a further embodiment of the toilet system according to the invention, the flush water and, consequently, the flush water circuit, can be completely eliminated. This simplifies the system by reducing the number of its components, and reduces the maintenance and repair effort. By applying suction through the toilet bowl outlet during the toilet bowl emptying process, an airflow is sucked from the surrounding environment into the bowl and downwardly to the bowl outlet, which assists in sweeping and removing the fecal and urine waste from the nano-coated waste-contacting surfaces of the bowl downwardly to the bowl outlet. Optionally, the airflow can be enhanced or especially directed along the waste-contacting surfaces by airflow directing means such as an air jet arrangement (passive or active) or simple airflow openings that direct the airflow toward and along the waste-contacting surfaces. By means of this airflow, it is possible to achieve good cleansing of the nano-coated waste-contacting surfaces of the toilet bowl, with or without a minimum of flush water, or simply with a very small amount of a deodorizer and disinfectant.

Problems solved by technology

Transportation vehicles, particularly aircraft, have only a limited capacity for carrying flushing liquid for rinsing or flushing toilets and waste water.

In other words, such systems do not have any waste-contacting surfaces in the toilet bowl or waste lines, because the waste is fully encapsulated in a wrapper.

Such systems are not well suited to applications in commercial passenger transport vehicles, because they are not sufficiently robust and reliable.

Such items will inevitably puncture the waste-encapsulating wrapper, causing feces to directly contact, soil and adhere to the inner surfaces of the toilet bowl and waste line.

Also in such systems, the wrapper-providing arrangement is very subject to failure, and / or requires proper operating efforts and procedures by the toilet user.

This is particularly true for large capacity aircraft that fly long distances (i.e. long flight durations) and, accordingly, must otherwise carry an enormous amount of water.

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