公开(公告)号：US4831419A

公开(公告)日：1989-05-16

申请号：US155349

申请日：1988-02-12

申请人： Thomas C. Iaia, Jr. ,  James A. Herley ,  Roger C. Male ,  William J. McLaughlin ,  Douglas A. McKeown ,  Robert W. Schaffer ,  Robert P. Siegel ,  Charles W. Spehrly, Jr.

发明人： Thomas C. Iaia, Jr. ,  James A. Herley ,  Roger C. Male ,  William J. McLaughlin ,  Douglas A. McKeown ,  Robert W. Schaffer ,  Robert P. Siegel ,  Charles W. Spehrly, Jr.

IPC分类号： G03B27/62 ,  B65H5/02 ,  B65H5/22 ,  G03B27/64 ,  G03G15/00 ,  G03G15/04

CPC分类号： B65H11/005 ,  B65H5/224 ,  G03B27/64 ,  B65H2406/323

摘要： A document handler 20 for presenting documents to the platen 23 of a copier 10 for copying with a vacuum belt platen transport system 32 having document transporting belts 35 movable under a substantially planar vacuum plenum backing and imaging background surface 33a overlying the platen, and a vacuum system 33 for applying a partial vacuum to a document sheet being transported by the movable belts over the platen; with a clamping and unclamping system for moving the vacuum plenum backing and imaging background surface 33a against the platen 23 to flatten the belts 35 and a document thereon against the platen for copying. During unclamping the surface 33a slightly fits away from the platen, while supplying the partial vacuum to lift a document away from the platen retained on the belts, by first lifting a first side of the surface 33a up away from the platen substantially before the opposite side, and then subsequently lifting the opposite side, to generate a controlled air flow for assisting in retaining the documents to the belts, and moving the belts when the surface is lifted away from the platen. During clamping the first side of the surface 33a moves towards the platen beginning slightly before the opposite side to generate a controlled air flow expulsion of air.