System for providing letter envelopes with means for tear-open opening

摘要

A system for the production of tear-open envelopes of the type with a closing flap and provided with a reinforcing thread or tape applied to the inside face of the envelope, parallel to the flap folding line. It comprises collection of each envelope from a loader and sending it flat onto a conveyor, application of reinforcing tape to the inside face of each envelope after opening the flap, if closed, cutting of the reinforcing tape in the required length and marking a tearing trace astride of the folding line and of the tearing tape.