An image reading device includes an image reading unit that reads an image while moving in a sub-scanning direction, a casing that houses the image reading unit, a supporting member attached to a lower surface of the casing and having a pair of inclined surfaces that are inclined bilaterally symmetrically outward in a direction intersecting the sub-scanning direction while extending downward, and a guiding member provided in contact with the supporting member and extending in the sub-scanning direction, the guiding member guiding the supporting member movably relative to the guiding member.

In a reading device, a light transmissive member has a front surface on which an original is placed. A peripheral member is adjacent to the light transmissive member, and includes a back surface in which a reference hole is formed. The reference hole includes a first edge and a second edge intersecting with each other. A reading sensor faces the back surface of the light transmissive member and the back surface of the peripheral member. The controller controls the reading sensor to read a reading range including the reference hole to obtain a read image, and determines a reference position in the reading range based on the read image. The reference position is determined to an intersection between the first edge and the second edge. The controller sets a reading start position based on the reference position.

According to one embodiment, an image forming apparatus includes a document platen, a document cover for covering the document platen during scanning, the document cover having a through-hole into which an original document can be inserted for placement on the document platen for scanning while the document cover is covering the document platen, a scanner that scans the original document on the document platen to image data corresponding to the original document, and a printing unit that prints an image of the original document corresponding to the image data obtained by the scanner.

An image reading apparatus includes an image scanning unit that is provided with a holding portion holding a flexible flat cable. The holding portion is protruded toward an upstream side in a sub scanning direction, and provided with a second wall part. The flexible flat cable that is extended from a connector is brought into contact with the second wall part. As for the flexible flat cable, a downward movement is regulated by a lower holding portion and an upward movement is regulated by an upper holding portion. Accordingly, the flexible flat cable does not rise.

An image reading apparatus includes a detection unit provided at a position separated from a positioning portion by a predetermined distance in a first direction, a discriminator configured to determine a length, in the first direction, of a document, and a setting unit that sets a start position to a first position if a detection position at which the detection unit detects the document is not included in a range, in a second direction, of the transparent member that is covered by the document, and sets the start position to a second position if the detection position is included in the range and the detection unit does not detect the document, wherein, in the first direction, the distance between the first position and the positioning portion is larger than the distance between the second position and the positioning portion.

An image reading device includes an image reading unit that reads an image while moving in a sub-scanning direction, a casing that houses the image reading unit, a supporting member attached to a lower surface of the casing and having a pair of inclined surfaces that are inclined bilaterally symmetrically outward in a direction intersecting the sub-scanning direction while extending downward, and a guiding member provided in contact with the supporting member and extending in the sub-scanning direction, the guiding member guiding the supporting member movably relative to the guiding member.

An image reading device includes an image reading section, a document table, a document pressing member, and a document size indication section. The image reading section reads an image of a document. The document table is located above the image reading section. The document is loaded on the document table. The document pressing member is provided over the document table in an openable and closable manner to press the document. The document size indication section is located on the document table and indicates a plurality of document sizes. The document size indication section is constituted by a semitransparent resin plate and includes a letter presenting portion. A part of the semitransparent resin plate of the document size indication section corresponding to the letter presenting portion has a smaller thickness than a part of the document size indication section other than the part thereof corresponding to the letter presenting portion.

An image reading apparatus includes a line image sensor receiving a light reflected from an original illuminated by a light source to generate image data, an original size detector disposed away from an original positioning portion by a predetermined distance in a sub-scanning direction, an original image reading start instructing unit outputting an image reading start instruction for starting an image reading operation when being depressed by a user, and a controller determining a size of the original based on detection results of the line image sensor and the original size detector when the size of the original is not stored in a memory in a case in which the controller receives the image reading start instruction in a state in which it is detected that an angle of a pressure plate is greater than a predetermined angle.

An image reading apparatus includes a detection unit provided at a position separated from a positioning portion by a predetermined distance in a first direction, a discriminator configured to determine a length, in the first direction, of a document, and a setting unit that sets a start position to a first position if a detection position at which the detection unit detects the document is not included in a range, in a second direction, of the transparent member that is covered by the document, and sets the start position to a second position if the detection position is included in the range and the detection unit does not detect the document, wherein, in the first direction, the distance between the first position and the positioning portion is larger than the distance between the second position and the positioning portion.

A sheet reading apparatus includes a sheet table on which a sheet is placed, a conveyor configured to convey the sheet, a reading guide configured to guide the sheet conveyed by the conveyor, and a reading device configured to read a shadow of the sheet conveyed by the conveyor, for detection of an inclination of the sheet. The sheet reading apparatus further includes a transparent member disposed at a position on a reading line of the reading device. The position on the reading line is withdrawn from the sheet and adjacent to the reading guide.