Canon Production Printing Holding B.v.

Christopher J Borchert

Peter J W Van Dongen

Anne A Wind

Hermanus M Kuypers

Dominique M L Perdaen

Müge Artar

Ronnie E A Blom

Ronnie EA Blom

Peter JW Van Dongen

A method of printing and stacking sheets improves the relative alignment of images in a stack of printed sheet. The method includes feeding a sheet at least twice past a printhead assembly for printing an image on both sides of the sheet, wherein in the first and second passes the respective front and back images are aligned with respect to a first edge of the sheet by detecting a skew angle between the first and second edges and applying the skew angle to align the front and back images; and stacking the sheet, wherein the sheet is registered to a predetermined stacking reference direction by one of its edges, and wherein during the stacking, the sheet is registered by its first edge.

Registration of duplex printed sheets in a sheet stacking device

To prevent deformation to relatively stiffer sheets during flipping, while ensuring reliable holding of relatively weaker sheets, a method for stacking sheets received from a printer by a sheet flipping device includes at least one slot for receiving a leading portion of a sheet. The method includes determining a respective insertion depth parameter for a first and a second sheet, wherein the second sheet has a greater stiffness than the first sheet; inserting a length of the first sheet into the at least one slot in correspondence with its respective insertion depth parameter, followed by flipping said first sheet; inserting a length (D) of the second sheet into the at least one slot in correspondence with its respective insertion depth parameter, followed by flipping said second sheet, wherein the inserted length of the first sheet is greater than that of the second sheet.

Inkjet sheet printer with a sheet stacker comprising a sheet flipping device

To ensure reliable and productive processing of printed sheets into stacks, a sheet stacker includes: a flipping device for flipping a sheet with respect to the sheet's orientation before being received by the flipping device onto a stack support or a stack of sheets on the stack support; a sensor assembly for detecting an out-of-plane deformation of a top sheet with respect to the underlying stack support or a stack of sheets on the stack support at least for each sheet added to the stack; and a controller configured to determine from data from the sensor assembly whether the top sheet was successfully flipped and stacked.

Sheet stacker with sheet flipping confirmation

Growing community of inventors

Venlo, Netherlands

Christopher J Borchert