Definitions

Envelope monitoring has established itself as the standard technology for effective and sensitive monitoring of production processes in series production. In a learn procedure, the monitoring systems automatically record the typical signal sequences, e.g. from force sensors, and store them as target curves for the currently running parts. The curve of each subsequently manufactured part is compared with the learned target curve. The so-called envelopes are used as limits, which are automatically set by the monitoring system around the scatter range of the signal paths. The width of the envelopes can be automatically set to achieve the best possible fit to the process variation and thus the best possible monitoring results.

It is also possible to move the limits manually. Impermissible deviations lead to an immediate shutdown of the machine in order to avoid further defective parts, and to protect machine and tool against overload. Alternatively, in the case of envelope violations, the affected error parts can be rejected by sorting gates, which are automatically controlled by the monitoring system. Sophisticated algorithms ensure that even minor errors are detected reliably, while avoiding unnecessary machine shutdowns as far as possible.