Stacking device and method for sorting

A method for sorting signatures into sheet stacks, wherein the signatures, which are folded sheets, are sequentially conveyed by a first conveyance unit to a second conveyance unit comprising a pair of conveyance members at least one which is configured to be driven to rotate, the method comprising:

• sequentially conveying the signatures through the pair of conveyance members to a stacking unit while sandwiching the signatures between the pair of conveyance members by means of continuous rotation of the conveyance members;
• in response to passage of a last signature for a sheet stack through the pair of conveyance members, switching the conveyance members from the continuous rotation to intermittent rotation or stop to cause the pair of conveyance members to keep the signatures for a next sheet stack from being conveyed to the stacking unit;
• in response to the stacking unit becoming ready to receive the signatures for a next sheet stack, switching the conveyance members from the intermittent rotation or stop to the continuous rotation to cause the pair of conveyance members to convey the signature for the next sheet stack to the stacking unit;
• and
• continuing to sequentially convey the signatures while the conveyance members are in a state of the intermittent rotation or stop.

A stacking device for stacking signatures, comprising:

• a first conveyance unit configured to sequentially convey the signatures, which are folded sheets;
• a second conveyance unit comprising a pair of conveyance members arranged for receiving the signatures from the first conveyance unit, at least one of the conveyance members being configured to be driven to rotate, the second conveyance unit being configured to convey the signatures through the pair of conveyance members by means of rotation of the pair of conveyance members while sandwiching both sides of the signatures between the pair of conveyance members;
• a stacking unit configured to stack the signatures conveyed from the second conveyance unit;
• a first sensor configured to detect the signatures that have passed through the pair of conveyance members;
• a second sensor configured to detect when the stacking unit is ready to receive the signatures;
• and
• a controller configured to control rotation of the at least one of the conveyance members based on a feedback from the first sensor and a feedback from the second sensor,
• wherein, when it is determined based on the feedback from the first sensor that a predetermined number of the signatures have passed the pair of conveyance members, the controller is configured to switch the conveyance members from continuous rotation to intermittent rotation or stop,
• wherein, when the conveyance members are in intermittent rotation or stopped, the controller is configured to convey the signatures stacked in the stacking unit, wherein, when the conveyance members are in intermittent rotation or stopped, and when it is determined based on the feedback from the second sensor that the stacking unit is ready to receive the signatures, the controller is configured to switch the conveyance members from the intermittent rotation or stop to the continuous rotation, and
• wherein the first sensor comprises a signature sensor arranged to detect passage of the signatures downstream of the first conveyance unit and upstream of the second conveyance unit.