A printing apparatus includes a transport mechanism for transporting a transport roll paper, a first slack detection sensor and a second slack detection sensor, or a label detection sensor driven at a predetermined cycle, a high-pass filter circuit to which detection voltages of the first slack detection sensor and the second slack detection sensor, or the label detection sensor are inputted, and an SOC (control circuit) for determining presence or absence of the transport roll paper or a label attached to a label sheet by comparing a detection voltage that has passed through the high-pass filter circuit with a predetermined threshold value.

An image reading device includes a magnetizer that magnetizes a metal object attached to a document, a magnetism detector that is disposed on the downstream side of the magnetizer in a document transport direction from a document stacking table toward the document transport path and detects residual magnetism of the metal object, and a metal object accompaniment determination unit that determines whether or not the metal object is attached to the document based on a detection result by the magnetism detector.

A method of detecting feeding status and width of paper is disclosed in this present invention, steps of the method include: step a, using at least one infrared light transmitter to transmit infrared light signals; step b, using a light-gathering element to gather together the infrared light signals transmitted by the infrared light transmitter; step c, using a light receiver to receive the infrared light signals gathered together by the light-gathering element, when paper is fed forward, the paper will be located between the infrared light transmitter and the light-gathering element, and will cover a part of the light-gathering element so as to cut off a part of the infrared light signals, how many infrared light signals the light receiver received will be changed, a feeding status and a width of the paper is determined according to how many infrared light signals the light receiver received.

An image reading apparatus includes: a reading unit, which is configured to read an original placed on an original table in a main scanning direction by irradiating the original with light; and a sub-scanning size detector, which is configured to detect presence or absence of the original on the original table by radiating invisible rays. When the platen cover forms an angle of equal to or smaller than a first angle with respect to the original table, the image reading apparatus determines a size of the original in a sub-scanning direction in accordance with a detection result acquired from the sub-scanning size detector. When the platen cover forms an angle equal to or smaller than a second angle, which is smaller than the first angle, with respect to the original table, the image reading apparatus determines a size of the original in the main scanning direction.

An image reading apparatus includes a sheet supporting portion configured to support a sheet, a sheet feeding portion configured to feed the sheet, a reading unit configured to read an image on the sheet, a body portion including a conveyance path configured to guide the sheet fed by the sheet feeding portion to the reading unit, a first detection unit including a first moving portion configured to be in contact with the sheet and move, and a first detection portion configured to detect the first moving portion, a second detection unit including a second moving portion configured to be in contact with the sheet and move, and a second detection portion configured to detect the second moving portion, and a support member supported detachably on the body portion, and configured to support the first and second detection portions.

An image reading apparatus compares a difference in luminance value between a pixel of interest in image information acquired via a reading unit and a pixel separated from the pixel of interest by a first distance with a first threshold value. Further, the image reading apparatus compares a difference in luminance value between the pixel of interest and a pixel present within a range to a pixel separated from the pixel of interest by a second distance that is larger than the first distance with a second threshold value. The image reading apparatus determines whether or not the pixel of interest is an edge pixel at an original end portion based on results of those comparisons, and determines an original size based on a result of the determination.

An image forming apparatus including a rotatable operation unit for information display and data input and configured to form an image on a sheet includes a tilt drive unit configured to rotate the operation unit, a tilt motor configured to drive the tilt drive unit, a volume sensor configured to detect a rotation position at which the operation unit is rotated, and a CPU configured to control rotation of the operation unit by driving the tilt motor based on a detection result acquired by the volume sensor, wherein the CPU prohibits a first rotation operation for rotating the operation unit to a predetermined position if the first rotation operation is not finished within a first predetermined time, and cancels the prohibition of the first rotation operation if a second rotation operation for rotating the operation unit to a standby position is finished within a second predetermined time.

Certain embodiments provide a document detecting device, including: a plate having an upper surface on which a document is placed; an imaging device that includes the upper surface in a photographing visual field range; and a controller that detects any one or more of a position, an angle, and a size of the document on the upper surface according to an image by the imaging device and fixed-size information of the document stored in advance.

A controller of an image reading apparatus is configured to cause the reading device to read an image on an original with moving a reading location from a first position to a second position, after reading the image on the original with moving the reading location from a third position to the first position, the third position being a position between the first position and the second position and spaced from the first position by a particular distance and determining a width of the original in the main scanning direction. The controller is configured to further move the reading location from the second position to the first position, and detect an instruction to continue reading a subsequent original during a period before the reading location reaches the third position. When the instruction is detected, the controller stops moving the reading location when it reaches the third position.

An image reading apparatus includes a first scanner provided in a housing, a conveyance unit, and a first calibration member. The conveyance unit is provided with a separation unit which separates the first calibration member upward from the first scanner. When the first calibration member is separated, the separation unit releases connection between the conveyance unit and the housing.