A print head assembly includes the feature of snap-in, tool-less replaceability. The print head is intended for an application where extended use is expected and replacement, due to wear, will be necessary by nontechnical users of the printing system. In one embodiment, the print head utilizes two pins...http://www.google.fr/patents/US4896166?utm_source=gb-gplus-shareBrevet US4896166 - Replaceable thermal print head assembly
