Print head having cup shaped protective member

Claim 1

IN STYLUS PRINTING APPARATUS FOR ELECTRICALLY PRINTING ON CHEMICALLY TREATED RECORD MATERIAL IN THE FORM OF A TAPE WHICH IS MOVABLE LONGITUDINALLY PAST A PRINTING STATION, A PRINTING HEAD HAVING A PLURALITY OF STYLI ELECTRODES IN CONTINUOUS CONTACT WITH ONE SURFACE OF SAID TAPE, SAID STYLI ELECTRODES BEING ELECTRICALLY INSULATED ONE FROM THE OTHER, MEANS FOR MOVING SAID PRINTING HEAD IN TRANSVERSE EXCURSIONS WITH RESPECT TO SAID TAPE AT SAID PRINTING STATION, ELECTRIC CIRCUIT MEANS ENERGIZALE FOR SELECTIVELY CAUSING PULSES OF CURRENT TO FLOW SIMULTANEOUSLY FROM A PREDETERMINED COMBINATION OF SAID STYLI ELECTRODES THROUGH SAID TAPE TO PRODUCE DISTINCT MARKS ON SAID RECORD SURFACE, AND ELECTRODE SHIELDING MEANS SURROUNDING SAID PRINT HEAD AND HAVING A PLURALITY OF APERTURES IN ALIGNMENT WITH SAID STYLI ELECTRODES, THROUGH WHICH SAID ELECTRODES PROTRUDE, SAID ELECTRODE SHIELDING MEANS HAVING AN OUTER SURFACE PORTION IN CONTACT WITH SAID ONE SURFACE OF SAID TAPE, AND ADAPTED FOR SLIDABLE ENGAGEMENT THEREWITH DURING SAID EXCURSIONS.