Sheet conveying device, image forming apparatus, and method of detecting double-feed of sheet

An image forming apparatus comprising:

• a document conveying unit including:
• a first roller configured to correct a tilt of an original document to be conveyed;
• a first detecting unit located further on an upstream side in a conveying direction of the original document than the first roller and configured to detect information concerning double-feed of the original document;
• a second roller configured to convey the original document to the first roller;
• and
• a driving unit configured to drive the second roller;
• a reading unit configured to optically read the original document conveyed by the document conveying unit;
• an image forming unit configured to form an image on a sheet on the basis of image data read by the reading unit;
• and
• a controller configured to control the driving unit to thereby temporarily stop the conveyance of the original document in order to perform the detection by the first detecting unit in a state in which an end of the original document on a downstream side in the conveying direction of the original document is located further on the upstream side in the conveying direction of the original document than a nip position of the first roller.