Punch unit, sheet post-processing apparatus having the same, and method of punching sheets
AssigneeToshiba Tec Kabushiki Kaisha
InventorKen Iguchi
Life of this patent
Estimating the term…
Abstract
A hole punch unit has a punching section, a longitudinal registering mechanism, and a transverse registering mechanism. The registering mechanisms incline the punching section in accordance with a skew of a sheet. The punching section thus corrected in position punches the sheet. The punching section is corrected in position, at both the leading edge of the sheet and the trailing edge thereof, thus increasing the precision of positioning the punching section and shortening the time required to position the punching section.
Claims2
A method of punching sheets by using a punch unit, comprising:
- a step of detecting a passage of the leading edge of a sheet at an upstream side of a punching section of the punch unit, which punches the sheet transported;
- a step of calculating a transverse-direction skew at the leading edge of the sheet, from the result obtained in the step of detecting a passage;
- a step of detecting a passage of the trailing edge of the sheet;
- a step of calculating a transverse-direction skew at the trailing edge of the sheet, from the result obtained in the step of detecting a passage;
- a step of rotating the punching section back and forth in the direction in which the sheet is transported and/or driving the punching section in the transverse direction of the sheet, in accordance with the skew detected at the leading edge or the trailing edge, thereby to orientate the sheet at right angles to the punching section;
- and
- a step of punching the sheet after adjusting the position of the punching section.
A method of punching sheets by using a punch unit having a punching-section rotating mechanism which has a rotation center existing outside the maximum width of the sheet and which rotates the punching section back and forth in the direction in which the sheet is transported and a lever shaft that rotates a tongue strip in accordance with the rotation of a longitudinal-registering motor, wherein the tongue strip of the punching-section rotating mechanism intersects at a right angle with the direction in which the sheet is transported and rotates in a longitudinal direction and a punching-section driving mechanism which moves the punching section in the sheet width direction, comprising:
- a step of detecting a passage of the leading edge of a sheet at an upstream side of a punching section of the punch unit, which punches the sheet transported;
- a step of calculating a transverse-direction skew at the leading edge of the sheet, from the result obtained in the step of detecting a passage;
- a step of detecting a passage of the trailing edge of the sheet;
- a step of calculating a transverse-direction skew at the trailing edge of the sheet, from the result obtained in the step of detecting a passage;
- a step of rotating the punching section back and forth in the direction in which the sheet is transported;
- a step of driving the punching section in the transverse direction of the sheet, in accordance with the skew detected at the leading edge or the trailing edge;
- a step of orientating the sheet at right angles to the punching section;
- and
- a step of punching the sheet after adjusting the position of the punching section.
Dependencies are inferred from the claim text.