Patent ID: 6860204

Claim:
An image exposure apparatus comprising: a rotating drum for winding a printing plate on which an image is recorded; a punch unit for forming punched holes to be used for positioning in printing processing on the printing plate; a conveying guide unit having a guide section that selectively moves to a first position facing the punch unit and a second position facing the rotating drum to guide a printing plate to the selected position so as to supply the printing plate; a pair of first positioning pins against which a front edge of the printing plate bumps when the conveying guide unit is located at the first position; a pair of second positioning pins against which the front edge of the printing plate bumps when the conveying guide unit is located at the second position; a width direction moving unit for moving in a width direction while a conveying pin is in contact with a width direction edge of the printing plate that is put on the conveying guide unit; a reference pin moving unit having a reference pin disposed at an opposite side of the width direction moving unit for defining the width direction edge of the printing plate, the reference pin moving unit moving the reference pin in accordance with a size of the printing plate; and a home position sensor mounted on a fixing portion independently of the conveying guide unit for detecting a home position of the reference pin.