An image forming apparatus includes a reverse roller pair configured to reverse a conveyance direction of a recording medium between a first direction and a second direction, a first conveyance roller pair configured to convey the recording medium in the first direction, and a second conveyance roller pair configured to convey the recording medium in the second direction. A first distance is between the first conveyance roller pair and a reversal position in which a trailing edge of the recording medium is located when the conveyance direction is reversed. A second distance is between the reversal position and the second conveyance roller pair. An absolute value of a difference between the first distance and the second distance is an integer multiple of a circumferential length of a drive roller of the reverse roller pair or within a predetermined range from the integer multiple.

A transport apparatus includes a speaker and a mike disposed at respective positions between which a transport path of a medium is interposed, where the speaker and the mike face each other, a drive circuit that outputs a drive signal to the speaker, an amplifier circuit formed by coupling a plurality of amplifiers in series, where the amplifier circuit amplifies and outputs an output signal of the mike, a processor to which the output signal of the amplifier circuit is input, an attenuation circuit disposed in a stage preceding a predetermined amplifier, where the attenuation circuit attenuates an input signal and outputs the input signal to the predetermined amplifier, and a switch that switches an attenuation factor by the attenuation circuit.

A medium conveying apparatus includes a feed roller to feed a medium, a separation roller opposed to the feed roller, a motor to generate driving force by being supplied with electric power, a cam member rotated in a first direction by the driving force to press the separation roller toward the feed roller, and a driving force transmitting mechanism between the motor and the cam member, the driving force transmitting mechanism being configured to transmit the driving force from the motor to the cam member and provided such that the cam member keeps pressing the separation roller toward the feed roller without rotating the cam member in a second direction opposite to the first direction even if electric power supply to the motor is shut off.

An example paper feed device includes a tray to feed printing paper, a magnetic force generation element to generate a magnetic flux, a 3D magnetic sensor to detect changes in the a density of the magnetic flux generated by the magnetic force generation element in each of three axes, and a controller. The tray has a movable element that is movable in relation to the printing paper. Either the magnetic force generation element or the 3D magnetic sensor is attached to the movable element. The controller determines the position of the movable element based on a detection signal received from the 3D magnetic sensor.

A method, apparatus and program product may evaluate a packaging material to determine various metrics associated with the packaging material. A test apparatus may be used to evaluate packaging material using a take up drum capable of sensing containment force imparted upon the drum by packaging material applied thereto, and in some instances, simulated flaws may be formed in a web of packaging material to evaluate a packaging materials response to such flaws when under tension.

According to some examples, a skew detection device comprises a first roller rotatable around a first axis, a second roller rotatable around a second axis, a first sensor, and a second sensor. The first sensor measures a first rotation parameter from the first roller and the second sensor measures a second rotation parameter from the second roller. A movement of a print media over the device rotates the first contact roller and the second roller, and a controller determines a skew of the print media based on the first and second rotation parameters captured by the first sensor and the second sensor.

According to an embodiment, a sheet conveying device detects double feeding of sheets by an ultrasonic wave oscillator and an ultrasonic waves receiver provided across a conveying path of the sheets. The sheet conveying device calibrates a threshold voltage on the basis of an offset voltage of an amplifier circuit when the receiver has not received ultrasonic waves.

Provided are a medium conveying apparatus, a control method, and a control program to enable more accurate detennination whether a medium conveyance abnormality has occurred. A medium conveying apparatus includes an ultrasonic transmitter capable of outputting an ultrasonic wave, an ultrasonic receiver opposed to the ultrasonic transmitter, to receive the ultrasonic wave and output an ultrasonic signal corresponding to the received ultrasonic wave, a pressure detection module to detect atmospheric pressure, based on the ultrasonic signal, a sound receiver to receive a sound and generate a sound signal corresponding to the received sound, an abnormality determination module to determine whether a medium conveyance abnormality has occurred, based on the sound signal, and a modification module to modify sensitivity of the sound receiver, correct the sound signal, or modify a criterion for determination of a medium conveyance abnormality by the abnormality determination module, based on the atmospheric pressure.

An image processing apparatus includes a transmitter, a receiver, a comparison circuit, and a control unit. The transmitter transmits an ultrasonic wave to a conveyance path through which a sheet is conveyed. The receiver faces the transmitter with the conveyance path in between, and receives the ultrasonic wave transmitted by the transmitter. The comparison circuit compares a level signal indicating a reception level of the ultrasonic wave received by the receiver with a threshold signal for determining whether or not the sheet is double-fed in the conveyance path, and outputs a comparison result signal according to the comparison result. The control unit determines whether or not there is a possibility of a defect in the double feed detection function of detecting double feed based on the comparison result signal and the level signal.

A sheet feeding apparatus includes a stacking unit including a plate, a feeding unit including a roller, a holder including a detected member, a drive unit and a controller. The detected member is positioned in a first position where the detected member is not detected by a detector in a case that the feeding unit is new, and is moved from the first position to a second position where the detected member is projected so as to be detected by the detector when the new feeding unit is mounted on the holder and the roller is driven. The controller controls the drive unit to perform up-and-down operation of the plate so that the plate is set to a feedable state of the sheet in a case that the feeding unit is mounted, and determines whether or not the feeding unit is new based on a detection result of the detector.