Platen adjusting means for typewriters

Claim 1

IN A TYPEWRITER OR SIMILAR OFFICE PRINTING MACHINE HAVING A PLATEN ROLL FORMED AT ITS ENDS WITH A PAIR OF END SHAFTS, A PAIR OF FRAME MEMBERS SUPPORTING SAID PAIR OF SHAFTS, SAID PLATEN ROLL BEING REMOVABLE FROM SAID FRAME MEMBERS, AND PRINTING MEANS MOVABLE TOWARD SAID PLATEN ROLL FOR EFFECTING IMPRINTS, A DEVICE FOR ADJUSTING THE POSITION OF SAID PLATEN ROLL WITH RESPECT TO SAID PRINTING MEANS ACCORDING TO THE THICKNESS OF THE WORK SHEET AND NUMBER OF COPIES, COMPRISING IN COMBINATION: (A) A PAIR OF PART-CIRCULAR ELEMENTS, EACH ONE ROTATABLY MOUNTED ON A CIRCULAR PORTION OF A RADIALLY OPEN SLOT PROVIDED ON EACH ONE OF SAID PAIR OF FRAME MEMBERS, (B) A SADDLE PROVIDED ECCENTRICALLY ON EACH ONE OF SAID ELEMENTS AND ADAPTED TO ROTATABLY SUPPORT THE CORRESPONDING SHAFT OF SAID PAIR, SAID SADDLES BEING RADIALLY OPEN IN THE SAID FRAME MEMBERS IN THE SAME DIRECTION AS THE SAID SLOTS THEREBY TO ENABLE REMOVAL OF SAID PLATEN ROLL, (C) THE CIRCULAR PORTIONS OF SAID SLOTS AND THE PARTCIRCULAR MAGNITUDE OF SAID ELEMENTS BEING IN EXCESS OF 180 DEGREES IN ORDER TO PREVENT REMOVAL OF SAID ELEMENTS FROM SAID FRAME MEMBERS WHEN SAID PLATEN ROLL IS REMOVED FROM THE LATTER, (D) AND MEANS INCLUDING MANIPULATIVE MEANS FOR SIMULTANEOUSLY ROTATING SAID CIRCULAR ELEMENTS TO ADJUSTABLY DISPLACE SAID PLATEN ROLL WITH RESPECT TO SAID PRINTING MEANS.