Sheet stacker with sheet flipping confirmation
AssigneeCanon Production Printing Holding B.V.
InventorsPeter J. W. Van Dongen, Dominique M. L. Perdaen, Christopher J. Borchert
Life of this patent
Estimating the term…
Abstract
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.
Claims15
A sheet stacker comprising:
- a flipper for flipping a sheet with respect to an orientation of the sheet before being received by the flipper onto a stack support or a stack of sheets on said stack support;
- sensors arranged for detecting an out-of-plane deformation of a top sheet with respect to the stack support or the stack of sheets on said stack support at least for each sheet added to the stack;
- and
- a controller configured to determine from data from the sensors whether the top sheet was successfully flipped and stacked,
- wherein the sensors and the stack support are movable with respect to one another,
- wherein the sensors define a detection position and are arranged such that the detection position is at the top of the stack during an entire stack forming process,
- wherein the sensors further comprise an optical emitter configured for emitting a light beam towards the top sheet and a detector,
- wherein the optical emitter and the detector are positioned with respect to one another such that an intensity of light received by the detector from the emitter is different when the top sheet is planar as compared to when the top sheet is non-planar, and
- wherein the light beam is parallel to an undeformed top sheet.
A method for stacking sheets comprising the steps of:
- flipping a sheet onto a stack support or a stack on said stack support;
- and
- sensing whether the flipped sheet comprised an out-of-plane deformation for each sheet in the stack individually, followed by either:
- flipping a further sheet onto the sheet in case no out-of-plane deformation was detected;
- or
- preventing further flipping of sheets and emitting an error signal,
- deriving at least one flipping fault parameter from data from a detector;
- and
- transmitting information for the at least one flipping fault parameter to a database with a look-up table for determining a root cause of a flipping fault.
A sheet stacker comprising:
- a flipper for flipping a sheet with respect to an orientation of the sheet before being received by the flipper onto a stack support or a stack of sheets on said stack support;
- sensors arranged for detecting an out-of-plane deformation of a top sheet with respect to the stack support or the stack of sheets on said stack support at least for each sheet added to the stack;
- and
- a controller configured to determine from data from the sensors whether the top sheet was successfully flipped and stacked,
- wherein the controller is configured to derive at least flipping fault parameter from data from a detector of the sensors and to transmit information for the at least flipping fault parameter to a database with a look-up table for determining a root cause of a flipping fault.
Dependencies are inferred from the claim text.