This preview shows page 1. Sign up to view the full content.
Unformatted text preview: s thus been achieved by the contribution of all these research works (figure 1). Today, the quality of mechanical systems presents a weaker dispersion than in the Eighties. The mean quality of production also progressed in a score of years. The percentage of defects appearing during operation was strongly reduced. However each time the mechanism presents a failure, the malfunction appears at the first stage of work and leads to sudden fracture or blocking of the system. The failure modes are similar to the ones existing in electronic devices. On the previous years, the mechanisms were degraded in a gradual way whereas today the damage is quasi instantaneous. Breakdowns occur during the first cycles of loading or at low operation time. The failure mode of high quality mechanical systems is thus completely changed. 225
J.K. Davidson (ed.), Models for Computer Aided Tolerancing in Design and Manufacturing, 2 25 – 234. © 2007 Springer. 226
Quality J. M. Linares et al.
More Quality Less failure 1980 2000
Probability density of failures Year BUT Today:...
View Full Document
- Spring '10
- The Land