VACUUM TRANSFER APPARATUS FOR ROTARY SHEET-FED PRINTING PRESSES AND METHOD OF SUPPORTING A PRINTED SHEET DURING TRANSFER

摘要

A vacuum assisted sheet transfer assembly 10 has an array of support bars 46 which guide the unprinted side of a freshly printed sheet S along a curved transfer path P. The support bars overlie the airflow inlet 44 of a manifold housing 16, with the support bars providing smooth surfaces for engaging and supporting the unprinted side of the sheet material as it is pulled along the transfer path while simultaneously limiting the flow of inlet air through elongated inlet apertures 52, 54. As air is drawn through the inlet apertures 52, 54, the unprinted side of the sheet is drawn into engagement with the support bars as it moves along the sheet transfer path. The sheet transfer assembly 10 eliminates the need for conventional skeleton wheels and the like. Marking, smearing and smudging are prevented since the printed side of the sheet S is not handled or contacted in any way as the sheet is conveyed along the transfer path P. IMAGE