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.
Claims8
A method of punching sheets by using a punch unit having a punching section configured to punch a sheet transported, comprising:
- a step of calculating a transverse-direction skew of a sheet at an upstream side of the punching section of the punch unit which punches the sheet transported as a function of times at which the sheet passes through first and second sensors which are spaced apart in a line intersecting at right angles with a direction in which the sheet is transported, prior to transport of the sheet to the punch unit;
- a step of rotating the punching section back and forth in the direction in which the sheet is transported, comprising:
- rotating a lever shaft in accordance with the transverse-direction skew via rotation of a longitudinal-registering motor, connected to the lever shaft, thereby punch blades of the punching section are parallel to the transverse-direction of the sheet, and
- rotating a tongue strip via the lever shaft, wherein the tongue strip intersects at a right angle with the direction in which the sheet is transported and rotates in a longitudinal direction;
- 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 configured to punch a sheet transported, comprising:
- a step of sensing passage of a leading edge of a sheet at an upstream side of a punching section of the punch unit through first and second sensors which are spaced apart in a line intersecting at right angles with a direction in which the sheet is transported, prior to transport of the sheet to the punch unit;
- a step of calculating a first transverse-direction skew at the leading edge of the sheet as a function of a time at which the leading edge of the sheet passes through the first sensor and a time at which the leading edge of the sheet passes through the second sensor;
- a step of rotating the punching section back and forth in the direction in which the sheet is transported, comprising:
- rotating a lever shaft in accordance with the first transverse-direction skew via rotation of a longitudinal-registering motor connected to the lever shaft, thereby punch blades of the punching section are parallel to the first transverse-direction of the sheet, and
- rotating a tongue strip via the lever shaft, wherein the tongue strip intersects at a right angle with the direction in which the sheet is transported and rotates in a longitudinal direction;
- a step of sensing passage of a trailing edge of the sheet at an upstream side of a punching section of the punch unit through the first and second sensors prior to transport of the sheet to the punch unit;
- a step of calculating a second transverse-direction skew at the trailing edge of the sheet as a function of a time at which the trailing edge of the sheet passes through the first sensor and a time at which the trailing edge of the sheet passes through the second sensor;
- a step of rotating the punching section back and forth in the direction in which the sheet is transported in accordance with the second transverse-direction skew detected at the trailing edge, thereby punch blades of the punching section are parallel to the transverse-direction of the sheet;
- and
- a step of punching the sheet after adjusting the position of the punching section.
Dependencies are inferred from the claim text.