Abstract: A mask processor sets a mask area based on a shape of a print sheet read by an image sensor, masks an outer peripheral portion of a print image using the mask area, and causes a print engine to form a mask-processed print image. The mask processor (a) identifies a pixel in which the print sheet is detected in a line image obtained from an output of the image sensor, (b) detects a sub-scanning-direction reference position corresponding to an edge of the print sheet based on the number of pixels in which the print sheet is detected, and (c) sets a linear edge of the mask area at a line spaced apart by a specific number of offset lines from a line where the sub-scanning-direction reference position is detected toward a center of the print sheet.

Abstract: A mask processor sets a mask area based on a shape of a print sheet read by an image sensor, masks an outer peripheral portion of a print image using the mask area, and causes a print engine to form a mask-processed print image. The mask processor (a) identifies a pixel in which the print sheet is detected in a line image obtained from an output of the image sensor, (b) detects a sub-scanning-direction reference position corresponding to an edge of the print sheet based on the number of pixels in which the print sheet is detected, and (c) sets a linear edge of the mask area at a line spaced apart by a specific number of offset lines from a line where the sub-scanning-direction reference position is detected toward a center of the print sheet.

Abstract: An inkjet recording apparatus includes a recording head having a plurality of nozzles for ejecting ink, an endless conveying belt conveying a recording medium and having a plurality of openings through which ink is passed when the recording head performs flushing, a reading sensor for reading, in a first reading mode, information on openings in the conveying belt and, in a second reading mode, information on the recording medium on the conveying belt, an ejection control portion for controlling ejection of the ink from the recording head based on at least one of the information on the openings and the information on the recording medium, and a reading mode switching control portion for switching the reading mode of the reading sensor between the first and second reading modes.

Abstract: An ink ejection timing adjustment method on an inkjet recording apparatus includes an information acquiring step of acquiring at least recording medium information with a reading sensor, a printing step of printing a test pattern on a recording medium on a conveying belt, a calculating step of calculating a delay time by adding to a default set time a correction time corresponding to a correction value for ink ejection timing entered based on the printed position of the test pattern, and a setting step of setting the delay time as a predetermined time at the lapse of which after, as a result of the conveying belt turning, an opening passes a reading position a recording head starts to eject ink to the opening.

Abstract: A first chart is recorded on a recording medium by discharging ink from predetermined nozzles of a recording head at a plurality of discharge timings set in advance with the detection time point of the recording medium by a recording medium detection sensor as a reference time point, and a second chart is recorded alongside the first chart on the recording medium by discharging the ink from other nozzles of the recording head at a plurality of discharge timings set in advance with the detection time point of the recording medium by the opening detection sensor as a reference time point. A flushing timing, which is set with the detection time point of the opening by the opening detection sensor as the reference time point, is adjusted in accordance with an input of an instruction following the recording of the first chart and the second chart on the recording medium.

Abstract: A feeder includes a conveyance path, a conveyance roller that conveys a sheet along the conveyance path, a transmitter that emits a space propagating energy, a receiver that receives a reflected energy obtained by reflection of the space propagating energy, and an actuator mounted pivotably on a pivot shaft and including first and second legs extending in different directions from the pivot shaft. The first leg is disposed to extend to the conveyance path and abut against the sheet being conveyed along the conveyance path. The second leg has a reflective surface crossing a path of the space propagating energy. The actuator is pivoted by abutment of the sheet against the first leg. The reflective surface is formed so that the reflected energy obtained by the reflection of the space propagating energy on the reflective surface enters the receiver regardless of an angle of pivotal movement of the actuator.

Abstract: A processor measures a pulse interval for a plurality of rotational phases of a rotary encoder, respectively. Each time the pulse interval is measured, the processor accumulates a measured value, which is the pulse interval or a moving average of the pulse interval of time-series data in association with corresponding one of the plurality of rotational phases, and records the measured value in a storage device. The processor derives a plurality of reference values corresponding to the plurality of rotational phases. Each time the measured value is newly obtained, the processor derives a correction value of a time interval of ink ejection of the inkjet recording apparatus in accordance with a difference between the measured value that is newly obtained and a corresponding reference value. The corresponding reference value corresponds to one of the rotational phases which corresponds to the measured value that is newly obtained.

Abstract: An inkjet recording apparatus includes a recording head having a plurality of nozzles for ejecting ink, an endless conveying belt conveying a recording medium and having a plurality of openings through which ink is passed when the recording head performs flushing, a reading sensor for reading, in a first reading mode, information on openings in the conveying belt and, in a second reading mode, information on the recording medium on the conveying belt, an ejection control portion for controlling ejection of the ink from the recording head based on at least one of the information on the openings and the information on the recording medium, and a reading mode switching control portion for switching the reading mode of the reading sensor between the first and second reading modes.

Abstract: An ink ejection timing adjustment method on an inkjet recording apparatus includes an information acquiring step of acquiring at least recording medium information with a reading sensor, a printing step of printing a test pattern on a recording medium on a conveying belt, a calculating step of calculating a delay time by adding to a default set time a correction time corresponding to a correction value for ink ejection timing entered based on the printed position of the test pattern, and a setting step of setting the delay time as a predetermined time at the lapse of which after, as a result of the conveying belt turning, an opening passes a reading position a recording head starts to eject ink to the opening.

Abstract: A control portion sets, as a head line of test mask data, such a read pixel line of a plurality of read pixel lines of read data obtained by a reading portion by performing reading, the plurality of read pixel lines being orthogonal to the sheet conveyance direction, as is located at a position upstream of a read pixel line of the plurality of read pixel lines as is read at a time when a detection portion detects a leading end of the sheet, by a number of lines calculated by adding an initial number of offset lines to a reference number of lines, and sets, as a non mask region, a sheet read region of the test mask data, and replaces, with white pixels, pixels outside such a region of test image data as corresponds to the non mask region.

Abstract: In the check pattern of a check chart, among a plurality of ink discharge nozzles, a predetermined number of ink discharge nozzles in a main scanning direction are set to one block, and in each of the blocks, a plurality of check lines which are recorded by the one block and which are extended along a subscanning direction are drawn such that each time the check lines proceed a predetermined length in the subscanning direction, the check lines are sequentially shifted line by line in the main scanning direction. In the line detection step, a detection range is sequentially moved by the one block in the main scanning direction, whether or not the check line is present is detected and based on the position of the detected check line within the one block in the main scanning direction, the moved position of the subsequent block is corrected.

Abstract: A control portion sets, as a head line of test mask data, such a read pixel line of a plurality of read pixel lines of read data obtained by a reading portion by performing reading, the plurality of read pixel lines being orthogonal to the sheet conveyance direction, as is located at a position upstream of a read pixel line of the plurality of read pixel lines as is read at a time when a detection portion detects a leading end of the sheet, by a number of lines calculated by adding an initial number of offset lines to a reference number of lines, and sets, as a non mask region, a sheet read region of the test mask data, and replaces, with white pixels, pixels outside such a region of test image data as corresponds to the non mask region.

Abstract: In a method for detecting an ejection abnormality of a nozzle according to the present disclosure, a plurality of nozzles of a liquid ejection head are caused to execute an operation of ejecting liquids so that a nozzle check pattern including check areas each drawn solely by each of the plurality of nozzles and a solid pattern including a solid printed area are formed on part of a sheet. A first density value indicating a density value of a ground color of the sheet and a second density value indicating a density value of the solid pattern are acquired. A threshold value for detecting an ejection abnormality of each of the plurality of nozzles is derived from the first density value and the second density value. It is determined, using the threshold value, whether or not each of the check areas of the nozzle check pattern is drawn.

Abstract: An inkjet recording apparatus includes a shape reading unit that reads a shape of a conveyed recording medium, a line data generating unit that generates line data based on information of the shape of the recording medium read by the shape reading unit, a head unit that ejects ink to the conveyed recording medium, a mask data generating unit that specifies an ejection inhibition part to which ink is not ejected from each of the plurality of line data, and a print image data generating unit that combines the dot image data and the mask data so as to generate print image data.

Abstract: In a method for detecting an ejection abnormality of a nozzle according to the present disclosure, a plurality of nozzles of a liquid ejection head are caused to execute an operation of ejecting liquids so that a nozzle check pattern including check areas each drawn solely by each of the plurality of nozzles and a solid pattern including a solid printed area are formed on part of a sheet. A first density value indicating a density value of a ground color of the sheet and a second density value indicating a density value of the solid pattern are acquired. A threshold value for detecting an ejection abnormality of each of the plurality of nozzles is derived from the first density value and the second density value. It is determined, using the threshold value, whether or not each of the check areas of the nozzle check pattern is drawn.

Abstract: A method includes operating a computer of an image forming apparatus, using, as a target image, an adjustment image including a center image representing a center thereof in a width direction, to: perform test processing of generating a print image by superimposing an outline image on an adjustment image after further shifting the outline image in the width direction by a first distance, and then executing printing processing; and adjust a relative position such that each of a difference between the first distance and a length in the width direction of a margin region lying along one lateral edge of a sheet, and a spaced-apart distance between the center of the sheet in the width direction and the center of the adjustment image in the width direction, represented by the center image formed on the sheet, becomes 0.

Abstract: A method includes operating a computer of an image forming apparatus, using, as a target image, an adjustment image including a center image representing a center thereof in a width direction, to: perform test processing of generating a print image by superimposing an outline image on an adjustment image after further shifting the outline image in the width direction by a first distance, and then executing printing processing; and adjust a relative position such that each of a difference between the first distance and a length in the width direction of a margin region lying along one lateral edge of a sheet, and a spaced-apart distance between the center of the sheet in the width direction and the center of the adjustment image in the width direction, represented by the center image formed on the sheet, becomes 0.

Abstract: In an image forming apparatus, a first motor causes a first rotor to rotate. The first motor rotates based on a first drive signal. A second motor causes a second rotor to rotate. The second motor rotates based on a second drive signal. A reading unit is provided between the first rotor and the second rotor. Based on a read signal, the reading unit reads a paper sheet being conveyed line by line. In a first period, a read signal generation unit generates the read signal in accordance with a frequency of the first drive signal. In a second period, the read signal generation unit generates, as the read signal, a signal for reading the paper sheet being conveyed at a reference speed.

Abstract: In an image forming apparatus, a first motor causes a first rotor to rotate. The first motor rotates based on a first drive signal. A second motor causes a second rotor to rotate. The second motor rotates based on a second drive signal. A reading unit is provided between the first rotor and the second rotor. Based on a read signal, the reading unit reads a paper sheet being conveyed line by line. In a first period, a read signal generation unit generates the read signal in accordance with a frequency of the first drive signal. In a second period, the read signal generation unit generates, as the read signal, a signal for reading the paper sheet being conveyed at a reference speed.

Abstract: The flexible flat cable includes a plurality of conductive wires, an insulating covering member, and a reinforcing plate. The thin conductive wires are arranged in parallel with one another in a direction perpendicular to the thickness direction thereof. The insulating covering member covers faces of the conductive wires, on at least one side of the conductive wires in the thickness direction. The reinforcing plate covers and reinforces the end parts of faces of the conductive wires in the thickness direction. The faces on the other side of the conductive wires in the thickness direction include exposed faces adjacent to the end parts. The exposed faces are not covered with the reinforcing plate and covering member.