Konica Minolta, Inc.

Takaki Kato

Yuji Kobayashi

Masayuki Fukunaga

Yuta Tachibana

Hiroshi Yamaguchi

Satoshi Teshima

Hiroshi Hiraguchi

Harumitsu Fujimori

Toshiaki Tanaka

Isao Watanabe

Satoshi Chikazawa

Toshinori Inomoto

A movement amount detecting device performs discrete Fourier transform onto N-th image data and N+1-th image data, thereby generating N-th wave number space data and N+1-th wave number space data. The movement amount detecting device obtains a target speed of a sheet, and determines a cutoff value based on the obtained target speed and an exposure time in an image sensor. The movement amount detecting device calculates an amount of movement of the sheet based on a phase difference between the N-th wave number space data and the N+1-th wave number space data in a wave number component smaller than the cutoff value.

Movement amount detecting device, image forming apparatus, and movement amount detecting method

An image formation apparatus includes a conveyor configured to convey a moving element on which an image is formed, a generator configured to generate a first image and a second image by shooting the conveyed moving element at different timing, a detector configured to sense a first distance between the generator and the moving element at the time of shooting of the first image and sense a second distance between the generator and the moving element at the time of shooting of the second image, and a hardware processor configured to calculate a speed of conveyance of the moving element based on the first image, the second image, the first distance, and the second distance, and output the speed of conveyance.

Image formation apparatus, control method, and control program for calculating a speed of conveyance

An image forming apparatus includes: a conveying path on which a recording medium is conveyed; an image capturer that includes a light source and radiates light from the light source to capture the recording medium being conveyed at different timings to generate at least two images including a first image and a second image; and a movement amount calculator that calculates a movement amount of the recording medium between capturing timings of the first and second images, wherein the movement amount calculator: calculates an index distance which is a distance in a conveying direction of a pattern formed by reflected light from the recording medium; calculates a ratio between the index distance and a reference distance used for comparison with the index distance; and calculates a movement amount of the recording medium between the capturing timings of the first and second images.

Image forming apparatus calculating movement of recording medium

An image forming apparatus that transfers an image from an image carrier onto a sheet passing between the image carrier rotating and a transfer member includes a fixing unit configured to thermally fix the image on the sheet while nipping and conveying the sheet with a pair of fixing members after the transfer, at least one of the fixing members rotating; a measuring unit configured to measure surface movement speed of the sheet in a non-contact manner while the sheet is being conveyed by the fixing members; and a control unit configured to control rotation speed of the fixing members in accordance with a result of the measurement, to adjust speed of conveyance of the sheet to a target speed determined beforehand for peripheral speed of the image carrier, the control being performed while the sheet being conveyed is in contact with the transfer member and the fixing members.

Image forming apparatus controlling recording sheet conveyance speed

A moving amount detector that sets a movable member included in a device of a mounting destination or an object conveyed by the device as a detection target and detects a moving amount of the detection target includes: an imaging unit that repeatedly captures images of the detection target at a constant sampling period while the detection target moves; and a moving amount calculating unit that selects two images to be compared with each other among a series of images of the detection target captured by the imaging unit such that an imaging time difference between the two images is increased as a difference due to moving of the detection target is further generated between the two images and calculates a moving amount of the detection target based on the difference.

Moving amount detector and image forming apparatus including the same

A sheet feeder picking up and transporting sheets includes a transport unit transporting sheets along a sheet transport path one by one, a gap occurrence detection unit detecting, within a predetermined section of the sheet transport path, occurrence of a gap between sheets, and a controller controlling a timing of the transport of sheets according to a result of the detection. The gap occurrence detection unit includes a first detection unit and a second detection unit. The first detection unit is configured to detect light that is emitted toward the predetermined section, reaches a converging surface thereof across the predetermined section, and converged on a receiving element thereof. The second detection unit is configured to detect light reflected by a sheet passing through the predetermined section. The occurrence of the gap is detected based on outputs from the first detection unit and the second detection unit.

Sheet feeder, document reader, and image forming apparatus

A device for detecting a travel distance of a sheet is provided. The device includes a light source for irradiating the sheet surface; an imaging sensor for capturing an image of a pattern of the sheet surface by light reflected from the sheet; a discrete Fourier transformation portion for performing discrete Fourier transformation on two patterns obtained by image capturing at a time interval by the imaging sensor; a high wave number component removal portion for using a threshold determined based on a cycle of concave-convex of the sheet surface to remove a high wave number component from the two patterns having been subjected to the discrete Fourier transformation; and a travel distance calculation portion for determining a travel distance of the sheet based on a phase relationship between the two patterns from which the high wave number component removal portion has removed the high wave number component.

Device for detecting travel distance, image forming apparatus, and method for detecting travel distance

An emission unit of a displacement detector emits laser light to a range in a space in which a target moves. A detection unit detects a distribution of amounts of light reflected from a capture region in the predefined range. Based on a shift of speckle pattern indicated by a difference between the distributions of amounts of reflected light that the detection unit detects at different times, a calculation unit calculates a displacement of the target. A correction unit measures a speckle contrast from the distribution of amounts of reflected light, and based on an error between the measured value and a reference value, corrects the amount of laser light. The reference value is set to the value of a speckle contrast in a case in which the amounts of reflected light fall within the detectable range of the detection unit.

Displacement detector and image forming device having the same

A multi-feed detection apparatus for detecting multi-feed of a sheet conveyed along a paper path is provided. The apparatus includes a first movement amount sensor disposed on the paper path to face a first surface of the sheet to detect a movement amount of the sheet; a second movement amount sensor disposed, on the paper path, in a position at which the first movement amount sensor is disposed to face a second surface of the sheet to detect a movement amount of the sheet; and a determination portion configured to determine that a conveyance state of the sheet is multi-feed when a difference between the movement amount of the sheet detected by the first movement amount sensor and the movement amount of the sheet detected by the second movement amount sensor is equal to or greater than a threshold.

Multi-feed detection apparatus, sheet conveyance apparatus, and image forming apparatus

An image forming apparatus includes a conveyance sensor disposed near a pair of conveyance rollers so as to accurately detect an amount of movement of the recording paper, a conveyance delay determination unit to determine a conveyance delay of the recording paper, and a conveyance control unit to control drive for rollers. The conveyance delay determination unit obtains conveyance delay information from among information detected with the conveyance sensor, or the like, and accelerates a rotational velocity of the pair of paper feed rollers when the conveyance delay quantity exceeds a threshold.

Image forming apparatus

An image forming apparatus includes: a conveyance roller configured to convey recording sheets; a brush motor configured to drive the conveyance roller to rotate; and a control unit configured to control a rotational speed of the brush motor, wherein while the conveyance roller conveys a recording sheet, (i) the control unit applies voltage to an outer circumferential surface of a commutator of the brush motor to drive the brush motor to rotate by a predetermined rotation amount, so as to perform a cleaning operation to remove a film deposited on the outer circumferential surface, and (ii) the control unit reduces the rotational speed of the brush motor while not performing the cleaning operation, so as to correct a conveyance distance of the recording sheet.

Image forming apparatus which performs a cleaning operation to remove a film deposited in a motor

An image processing apparatus includes: a transport roller for transporting a sheet subjected to image processing; a motor that drives the transport roller to rotate; and a speed reduction unit that performs a speed reduction control on the motor to temporarily stop the sheet, the speed reduction control being performed in a manner that a stopping time and a stopping distance each satisfy a corresponding target range, wherein the speed reduction control includes: a first control that is a control of reducing a rotation speed of the motor to a reference speed through at least two operations from among a braking operation, a powering operation, and a free running operation; and a second control that is a control of, after a rotation amount of the motor from the start of the speed reduction control reaches a reference value, continuously performing the braking operation until the stop of the motor.

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Toyokawa, Japan

Takaki Kato