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.

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.

The invention is a modular card processing and attaching system configured to provide uninterrupted workflow in the feeding and subsequent attaching of cards to carriers for the formation of a mailpiece. The modular card processing and attaching system is further configured to be incorporated into a production mail inserter system, such that attached card and carrier mailpieces may be subsequently sorted and/or inserted into a mailable envelope or packages to be mailed.

There is described a sheet numbering process involving feeding of individual sheets (S) in succession, which individual sheets (S) each carry a plurality of imprints (P) that are arranged in a matrix of rows and columns, and providing unique serial numbers to multiple ones of the plurality of imprints (P) carried by the individual sheets (S). The sheet numbering process comprises numbering of at least some of the individual sheets (S), wherein numbering of the individual sheets (S) is selectively commutable between a first numbering scheme (N1) and at least a second numbering scheme (N2; N2′; N*), different from the first numbering scheme (N1), without interruption of the numbering process. The first numbering scheme (N1) involves providing all imprints (P) of a first subset (S.sup.0) of individual sheets (S) with a unique serial number (SN1) of the first numbering scheme (N1). The second numbering scheme (N2; N2′; N*) involves providing all or part of the imprints (P) of a second subset (S′; S*) of individual sheets (S) with a unique serial number (SN2; SN2′; SN*) of the second numbering scheme (N2; N2′; N*). The first subset (S.sup.0) of individual sheets (S) and the second subset (S′; S*) of individual sheets are sorted after numbering in dependence of the numbering scheme (N1; N2; N2′; N*). Also described is a sheet-processing machine for carrying out the aforementioned sheet numbering process.

There is described a sheet numbering process involving feeding of individual sheets (S) in succession, which individual sheets (S) each carry a plurality of imprints (P) that are arranged in a matrix of rows and columns, and providing unique serial numbers to multiple ones of the plurality of imprints (P) carried by the individual sheets (S). The sheet numbering process comprises numbering of at least some of the individual sheets (S), wherein numbering of the individual sheets (S) is selectively commutable between a first numbering scheme (N1) and at least a second numbering scheme (N2; N2′; N*), different from the first numbering scheme (N1), without interruption of the numbering process. The first numbering scheme (N1) involves providing all imprints (P) of a first subset (S.sup.0) of individual sheets (S) with a unique serial number (SN1) of the first numbering scheme (N1). The second numbering scheme (N2; N2′; N*) involves providing all or part of the imprints (P) of a second subset (S′; S*) of individual sheets (S) with a unique serial number (SN2; SN2′; SN*) of the second numbering scheme (N2; N2′; N*). The first subset (S.sup.0) of individual sheets (S) and the second subset (S′; S*) of individual sheets are sorted after numbering in dependence of the numbering scheme (N1; N2; N2′; N*). Also described is a sheet-processing machine for carrying out the aforementioned sheet numbering process.

Provided are a placement table configured to place a medium onto which liquid is discharged, a perforation member configured to perform perforation by imparting a shear force to the medium placed at the placement table, a die hole provided at the placement table, a perforation member moving section configured to move the perforation member between a standby position above the die hole and a perforating position at which the perforation member enters the die hole, and a control unit configured to control operation of the perforation member moving section, wherein when the control unit obtains perforation failure information during perforating operation in which the perforation member starts moving from the standby position and moves through the perforating position to the standby position, the control unit is configured to control the perforation member moving section so that a shear force is again imparted to the medium.

Provided are a placement table configured to place a medium onto which liquid is discharged, a perforation member configured to perform perforation by imparting a shear force to the medium placed at the placement table, a die hole provided at the placement table, a perforation member moving section configured to move the perforation member between a standby position above the die hole and a perforating position at which the perforation member enters the die hole, and a control unit configured to control operation of the perforation member moving section, wherein when the control unit obtains perforation failure information during perforating operation in which the perforation member starts moving from the standby position and moves through the perforating position to the standby position, the control unit is configured to control the perforation member moving section so that a shear force is again imparted to the medium.

A medium stacking apparatus comprises a stacking surface for stacking a medium; a first guide to guide the stacking of the medium in the case of stacking of the medium and to press the medium in the case of separating of the medium stacked on the stacking surface; and a second guide that is capable of supporting the medium stacked on the stacking surface, the first guide including a first plate, and a second plate that is rotatably connected to the first plate, the second plate being rotated about the first plate in the case of stacking of the medium, and a portion or all of the second plate being overlapped with the first plate in the case of separating of the medium.

Certain examples described herein relate to a buffer unit for a printing system. In certain cases, a measurement device is used to obtain measurement data representing an optical property of a printed image on a substrate. A buffer unit receives the substrate downstream of the measurement device and places the substrate in a queue. In certain cases, a controller determines, based on the measurement data, whether the printed image comprises a defect. Responsive to determining that the printed image does not comprise a defect, the controller causes the substrate to be moved from the buffer unit to an output stack. Responsive to determining that the printed image comprises a defect, the controller causes the substrate to not be moved to the output stack.

Certain examples described herein relate to a buffer unit for a printing system. In certain cases, a measurement device is used to obtain measurement data representing an optical property of a printed image on a substrate. A buffer unit receives the substrate downstream of the measurement device and places the substrate in a queue. In certain cases, a controller determines, based on the measurement data, whether the printed image comprises a defect. Responsive to determining that the printed image does not comprise a defect, the controller causes the substrate to be moved from the buffer unit to an output stack. Responsive to determining that the printed image comprises a defect, the controller causes the substrate to not be moved to the output stack.