Nowadays, the main components of vacuum toilets for aircrafts are made of steel, individual and assembled in elements are produced separately differential design. This has adverse effects on weight and financial and time expenditures for manufacturing and assembly. However, regarding weight reductions the current design is considered to be exhausted. The aim of the project was to reduce the toilet system weight by approximately 15 % with a new design concept as well as to decrease assembly expenditures applying the integral design approach. The project was organized in five work packages. After specifying the requirements for the vacuum toilet different design variants were created by implementing the integral design approach. After a comparison of six options for the supporting structure in a FE- simulation one concept was selected. The concept transmitting the load to the supporting structure (two sandwich plates) included a plastic bowl and further integrated plastic elements. The third work package covered the detailed design. For the toilet bowl the material Polyphenylsulfid (PPS) was chosen. As adequate manufacturing process the research team selected the injection moulding system. A detailed overall design was set and suitable manufacturing tools for the supporting structure and the seat ring were drawn up. In a fourth step "Prototyping and Integration" AOA developed an optimized design and correspondent manufacturing process for the toilet bowl that made possible the small wall thickness that is required for light weight construction. Instead of a flexible flush hose in the bowl a flush duct was designed. The duct was integrated in the bowl by means of a conductive weiding procedure. The needed welding apparatus was designed and constructed within the framework of this project. As part of the verification process several tests were carried out as e.g. vibration tests, shock tests and acceleration tests that all specimens successfully passed. Furthermore, extensive tests were conducted at a system test rig. Withal, the water inlet within the toilet flush ring was revised. With a reduction of the system weight by 17% and a significantly higher integration degree of individual elements the main objectives have been achieved. However, the concept must be re-examined, in particular with regard to cost. Reducing the vacuum toilet weight AOA is able to contribute considerably to environmental friendliness and efficiency of future aircraft generations. There is a great customer interest in weight reductions of aircrafts, the newly gained technologies will be applicable to future aircrafts with vacuum systems (e.g. passenger aircrafts, regional and business jets). Therefore, this project will strengthen AOA's competitive position and will help to safeguard and create jobs at AOA and along the supply chain.
Hochintegrierte Vakuumtoilette (PROTEG-A). Schlussbericht. nationale Luftfahrtforschung 2007 - 2013. LuFoIV-3. Laufzeit des Vorhabens: 01.10.2010 - 31.03.2013
2013
30 Seiten, Bilder, Tabellen
Report
Deutsch
TIBKAT | 2010
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