Riassunto analitico
During their working life, wheel balancers are subjected to several stresses, due to both the correct and the incorrect use by the operator, in the different steps of the balancing procedure.
To prevent premature damaging of the equipment, it is important to develop test procedures, useful to understand statistically whether the production lot satisfies the quality requirements, or not. These procedures can be useful also in the design phase of a product, to quantify the fatigue resistance of different solutions for a same product or assembly.
In this thesis, the focus was mainly on a prototipe of an unbalance measurement assembly, mounted on a chassis that was already in production. The test procedures developed were an evolution of the preexisting ones, with additional optimized functions such as the more intensive use of automatic control, by means of feedback loops of the control variables. The new procedures added an important safety feature, that is the automatic stop of the test right when a failure occurs. This feature enables the test engineer to analyze the unit under test right after the failure, not including any more damages that could have occurred after the first one, leading to a difficult understanding of the failure mode.
After the design phase of each procedure, the necessary fixtures were realized, and tests were set up and carried on, each for a number of cycles corresponding to the life of the assembly under test. In the end, for each test and in all cases, a report was produced, to show any failures or plots of variables of interest as a function of time.
|