Impact printer with yielding platen

摘要

PCT No. PCT/IT96/00135 Sec. 371 Date Mar. 12, 1997 Sec. 102(e) Date Mar. 12, 1997 PCT Filed Jun. 28, 1996 PCT Pub. No. WO97/02954 PCT Pub. Date Jan. 30, 1997An impact printer (30) comprises a printhead (31) traversing along a guide for printing a line on a document (32) of thickness S, and is provided with contrast means for supporting the document (32) against the head (31) and for contrasting the impact force exerted by the latter against the document. The printhead (31) bears a spacing roller (34) which causes the contrast means to yield in order to compensate for thickness S, which varies according to the document (32), and thus maintain the distance D between the head (31) and the document (32) constant. The contrast means comprise a flexible platen (33) attached yieldingly at the ends, of length at least equal to or greater than that of the print line and having a variable section frame so that the pressure generated between the platen (33) and the roller (34) is substantially constant all along the print line.