Patent attributes
Disclosed are a sheet punching apparatus and a method for controlling the same in which the side end position of a sheet, its rear end position, a hole position, and the detachment state of a punch portion are sensed only by two sensors, and a punching hole can be formed at the exact position of a sheet by means of the two sensors. The sheet punching apparatus includes a punch portion (120) moving in a direction perpendicular to a moving direction of a sheet, a bracket (122) having an elastic member (12) to move in conjunction with the punch portion (120), a sheet side end sensing means (S10) fixed to a predetermined position of the bracket, sensing the side end of the sheet in accordance with movement of the bracket, and a sheet rear end sensing means (S20) opened to sense the rear end of the moving sheet when the bracket moves at a predetermined distance along with the punch portion to sense the side end of the sheet, wherein the punch portion (120) works to punch the sheet at a predetermined position after the rear end of the sheet is sensed by the sheet rear end sensing means.
