Patent ID: 8770581

Claim:
A skew correcting device comprising: a first roller pair configured to nip and convey a sheet; a second roller pair disposed upstream of the first roller pair and configured to nip and convey the sheet; a contact portion disposed downstream of the first roller pair, the contact portion being a portion that a leading edge of the conveyed sheet comes into contact to correct skew of the sheet; a separating mechanism configured to separate the first roller pair wherein, in a case that the separating mechanism separates the first roller pair before the leading edge of the conveyed sheet comes into contact with the contact portion to form a loop in the sheet for skew correction the loop is formed between the contact portion and the second roller pair, and in a case that the separating mechanism does not separate the first roller pair before the leading edge of the conveyed sheet comes into contact with the contact portion to form a loop in the sheet for skew correction, the loop is formed between the contact portion and the first roller pair; and a control unit configured to make a determination as to whether the separating mechanism separates the first roller pair or not separate the first roller pair on the basis of sheet information of the conveyed sheet.