A sheet conveyance device includes a transmitter circuit, a receiver circuit, an integrator circuit which performs charging of electric charge outputted from the transmitter circuit and outputs a judgment voltage, a drive circuit, and a control circuit. The drive circuit feeds a drive signal to the transmitter circuit. At a lapse of a wait time after changing a level of a transmission instruction signal to a level instructing to feed the drive signal to the transmitter circuit, the control circuit makes the integrator circuit start to perform charging. When adjusting the wait time, the control circuit performs processing for adjustment a plurality of times. The control circuit makes the wait time different in each execution of the processing for adjustment. The control circuit determines a new wait time based on a magnitude of the judgment voltage recognized in each execution of the processing for adjustment.

An image forming apparatus includes an image forming unit configured to form an image on a sheet being conveyed on a horizontal path and a double feed sensor configured to execute double feed detection processing of detecting a state in which a plurality of sheets being conveyed on the horizontal path are conveyed in a duplicate manner. The image forming apparatus includes a double feed detection function table, in which whether to enable or disable the double feed detection processing is set according to a type of a sheet. The image forming apparatus determines whether to execute the double feed detection processing at a time of image formation in accordance with sheet setting information including information on a characteristic of a sheet to be used for the image formation and setting information on whether to execute the double feed detection processing, and the double feed detection function table.

A transport device includes: a medium support unit having a placement surface where a sheet-like medium is placed; a transport unit supplied with the medium placed at the placement surface and transporting the medium in a transport direction along a sheet surface of the medium; an ultrasonic transmitting unit provided at a part of the medium support unit and transmitting an ultrasonic wave; an ultrasonic receiving unit provided at another part of the medium support unit, and receiving the ultrasonic wave and outputting a received signal; and a floating detection unit determining whether a floating of the medium from the placement surface is present or not, based on the received signal.

Provided are a multi-feed detection apparatus, a control method, and a control program to suitably determine whether or not the multi-feed detection apparatus returns a fed medium to a direction of a medium tray when multi-feed has occurred. A multi-feed detection apparatus includes an ultrasonic sensor to generate an ultrasonic signal, a multi-feed determination module to determine that feeding of the medium is normal when a signal value of the ultrasonic signal is equal to or more than a first threshold value, and determine that a multi-feed of the medium has occurred when the signal value of the ultrasonic signal is less than the first threshold value, and a control module to control the feed module to return the fed medium to a direction of the medium tray when the signal value of the ultrasonic signal is less than a second threshold value smaller than the first threshold value.

A sheet stacker includes a housing, a fence, a first distance measurement sensor, and a second distance measurement sensor. The fence is movable in a fence moving direction on the housing and is configured to regulate a position of an end of a sheet. The first distance measurement sensor is configured to measure a distance between the fence and a first portion of the housing, the first portion being on one side of the housing with respect to the fence in the fence moving direction. The second distance measurement sensor is configured to measure a distance between the fence and a second portion of the housing, the second portion being on another side of the housing with respect to the fence in the fence moving direction.

A transmitter transmits ultrasonic wave of a predetermined volume. A reflected ultrasonic wave receiver receives reflected ultrasonic wave, transmitted from the transmitter and reflected by a sheet. A permeated ultrasonic wave receiver receives permeated ultrasonic wave, transmitted by the transmitter and permeated through the sheet. A volume detector detects reflected volume of the reflected ultrasonic wave, and permeated volume of the permeated ultrasonic wave. The decider identifies a thickness of the sheet being transported by a transport device, and decides whether multifeed of the sheets is occurring, on a basis of a comparison result between the detected reflected volume and a reference reflected volume, and a comparison result between the detected permeated volume and a reference permeated volume.

A tape affixing apparatus includes a holding unit that holds a wafer and a ring frame, a peeling plate that peels off a dicing tape from a sheet by bending a tape set at an acute angle, an affixing roller configured to affix the dicing tape to the wafer and the ring frame by pressing the dicing tape peeled off from the sheet by the peeling plate against the wafer and the ring frame, an air nozzle that makes a distal end of the dicing tape peeled off from the sheet conform to an outside surface of the affixing roller, and an end detecting unit that detects the distal end of the dicing tape made to conform to the outside surface of the affixing roller.

There is provided a medium transporting device including: a medium placement section on which a medium is placed, a feeding roller feeding a medium from the medium placement section, a motion detection sensor detects a motion of a medium, and a controller that stops feeding of a medium based on a detection value received from the motion detection sensor, in which the motion detection sensor is a two-dimensional sensor including a light emitting section and a light receiving section and detecting a motion of a medium, the medium placement section is provided with a placement detector that acquires information relating to a presence/absence of a medium on the medium placement section, and the controller sets a state of the light emitting section to a non-light emitting state when detection information of the placement detector indicates that a medium is absent on the medium placement section.

An image scanner is configured to perform: controlling the sheet feed roller to feed the document supported on the sheet feed tray, controlling the conveyor to convey the fed document to the reading position, controlling the image sensor to read the image of the document at the reading position, and controlling the sheet discharge unit to discharge the read document to the sheet discharge tray; in response to detecting, by the sheet feed sensor, a state change from the first state to the second state, moving the movable plate upward until the sheet feed roller changes from the second state to the first state; after moving the movable plate, controlling the distance sensor to detect the document distance; and moving the sheet discharge unit vertically based on the detected document distance.

The present disclosure provides a feed module, which is applicable to an electronic device, for example, a multi-function product/printer/peripheral or printer and the like. The feed module comprises a carrier tray, a clamping piece, a first sensor and a control unit. A document is suitable for being placed on the carrier tray, and is driven by the feed module to be transferred into the multi-function product/printer/peripheral or printer. The clamping piece is movably assembled on the carrier tray. The first sensor senses the position of the clamping piece on the carrier tray. The control unit is electrically connected with the first sensor. After the document is placed on the carrier tray and clamped by the clamping piece, the control unit determines the width of the document by the first sensor.