Example implementations relate to media stacking mechanisms. In some examples, a printing device can include a stacking mechanism that includes a tamper to tamp print media positioned within the stacking mechanism, and a controller comprising instructions to: tamp a first sheet of print media received at the stacking mechanism a first distance based on a first size of the first sheet of print media, tamp a second sheet of print media received at the stacking mechanism a second distance based on the second size of the second sheet of print media, wherein the second sheet of print media is positioned over the first sheet of print media, and tamp a third sheet of print media received at the stacking mechanism the second distance when the third sheet of print media is the first size, wherein the third sheet of print media is positioned over the second sheet of print media.

This paper sheet processing device (100) for processing paper sheets is provided with: an identification unit (55) for identifying paper sheets; stacking units (60, 210) for stacking paper sheets on the basis of the content of classification types identified by the identification unit (55); and a control unit (50, 135, 550) that reads, from a memory unit (56, 136, 560) in which an upper limit of paper sheets to be stacked by the stacking units (60, 210) are stored in association with the content of classification types, the upper limit for paper sheets that correspond to the content of the classification types of the paper sheets stacked by the stacking units (60, 210), and sets the upper limit for paper sheets to be stacked by the stacking units (60, 210).

Example implementations relate to media stacking mechanisms. In some examples, a printing device can include a stacking mechanism that includes a tamper to tamp print media positioned within the stacking mechanism, and a controller comprising instructions to: tamp a first sheet of print media received at the stacking mechanism a first distance based on a first size of the first sheet of print media, tamp a second sheet of print media received at the stacking mechanism a second distance based on the second size of the second sheet of print media, wherein the second sheet of print media is positioned over the first sheet of print media, and tamp a third sheet of print media received at the stacking mechanism the second distance when the third sheet of print media is the first size, wherein the third sheet of print media is positioned over the second sheet of print media.

A sheet stacker includes a sheet conveyor arrangement and a stacker platform. The sheets are fed in a sheet feeding direction on the stacker platform, to form stacks of sheets thereon. The stacker platform supports a stack conveyor configured and controlled to move in a conveyor direction to move the stack under formation such that sequentially piled up jobs are placed in an approximately centered position one with respect to the other according to the sheet feeding direction.

A sheet stacker including a sheet conveyor arrangement and a stacking bay, wherein sheets delivered by the sheet conveyor arrangement are formed into stacks; the stacking bay including a stacker platform. The stacker platform is provided with a vertical lifting and lowering movement with respect to a stationary supporting structure and is controlled to move downwards while a stack of sheets is formed thereon. The stacker platform supports a stack conveyor configured and controlled to perform at least an evacuation motion, to remove a completed stack from the stacking bay. The evacuation motion of the stack conveyor is oriented such that a completed stack is moved from the stacking bay onto an evacuation conveyor arranged under the sheet conveyor arrangement.

This paper sheet processing device (100) for processing paper sheets is provided with: an identification unit (55) for identifying paper sheets; stacking units (60, 210) for stacking paper sheets on the basis of the content of classification types identified by the identification unit (55); and a control unit (50, 135, 550) that reads, from a memory unit (56, 136, 560) in which an upper limit of paper sheets to be stacked by the stacking units (60, 210) are stored in association with the content of classification types, the upper limit for paper sheets that correspond to the content of the classification types of the paper sheets stacked by the stacking units (60, 210), and sets the upper limit for paper sheets to be stacked by the stacking units (60, 210).

Provided is an image forming apparatus and a sorting method allowing paper sheets to be sorted by size or thickness from a bundle of documents that have been already printed with no need for adding a sensor, or the like, or during the time for printing preparation, or the like. The image forming apparatus includes a first detecting part, a paper discharging part and a control part. The first detecting part detects the pass of an edge part of the document. The control part determines the length of a document along the direction of conveyance from the time required from the moment when the document reaches the first detecting part to the moment when it pass the first detecting part, determining the sorting destination.

A sheet stacker includes a sheet conveyor arrangement and a stacker platform. The sheets are fed in a sheet feeding direction on the stacker platform, to form stacks of sheets thereon. The stacker platform supports a stack conveyor configured and controlled to move in a conveyor direction to move the stack under formation such that sequentially piled up jobs are placed in an approximately centered position one with respect to the other according to the sheet feeding direction.

A sheet stacker including a sheet conveyor arrangement and a stacking bay, wherein sheets delivered by the sheet conveyor arrangement are formed into stacks; the stacking bay including a stacker platform. The stacker platform is provided with a vertical lifting and lowering movement with respect to a stationary supporting structure and is controlled to move downwards while a stack of sheets is formed thereon. The stacker platform supports a stack conveyor configured and controlled to perform at least an evacuation motion, to remove a completed stack from the stacking bay. The evacuation motion of the stack conveyor is oriented such that a completed stack is moved from the stacking bay onto an evacuation conveyor arranged under the sheet conveyor arrangement.

A removable media tray for an imaging device having a rear media restraint coupled to a media length sensing system. A rear media restraint, slideably latchable to a track in the tray, has a rack that engages with a gear train that drives an encoder gear. As the rear media restraint is adjusted for different media lengths, the rack and gear train rotate the encoder gear. The encoder gear has a plurality of encoder tracks each track having a unique binary pattern. A sensor array of a plurality of sensors corresponding to the plurality of encoder tracks has a plurality of outputs that combine to form a digital signal fed to a controller in the imaging device allowing the controller to determine a media length based in the position of the rear media restraint.