An image input device is provided with an engagement assembly that releasably engages a document to hold the document on a carriage against the bias force of a biasing member. The engagement assembly includes a stop assembly that releasably engages the document and a release mechanism for releasing the original document from the stop assembly permitting the biasing member to urge the document in a discharge direction. The engagement can be operated either manually or by motor. The document can then be removed from the input device at any time except during the scanning operation.