High speed printer with ribbon-shift assembly for permitting printing in different ink

Claim 1

A MACHINE FOR PRINTING CHARACTERS FROM EITHER OF TWO INKING MEDIA ON THE SAME SURFACE OF THE SAME RECORDING MEDIUM, COMPRISING: AN ASSEMBLY OF TYPE FACES; A WEB IMPREGNATED WITH A FIRST INK AND ARRANGED BETWEEN SAID ASSEMBLY AND RECORDING MEDIUM SO THAT TYPE FACE IMPRESSIONS ON SAID WEB MAY BE TRANSFERRED AS CHARACTERS IN SAID FIRST INK ONTO THE RECORDING MEDIUM; A RIBBON IMPREGNATED WITH A SECOND INK; MOVABLE MEANS MOUNTING SAID RIBBON AND ARRANGED FOR INTERPOSITION OF SAID RIBBON BETWEEN THE WEB AND THE SAME RECORDING MEDIUM; SAID RIBBON INCLUDING AN INK-IMPERMEABLE MASKING MEDIUM SO ARRANGED THAT THE RIBBON, WHEN SO INTERPOSED, IS SEPARATED FROM THE WEB BY THE MASKING MEDIUM; AND MEANS FOR SELECTIVELY INTERPOSING THE RIBBON WHEREBY SELECTED TYPE FACE IMPRESSIONS MAY BE TRANSFERRED AS CHARACTERS IN SAID SECOND INK ONTO THE SAME RECORDING MEDIUM; TRANSFER OF FIRST AND SECOND INKS BETWEEN SAID WEB AND SAID RIBBON BEING PREVENTED BY SAID MASKING MEDIUM.