Abstract: A line sensor includes plural sensor chips and a gap between adjacent two sensor chips. In a test pattern image, a thin line is formed by ink ejected from a nozzle. Further, the line sensor scans the test pattern image on a sheet slanted from a transportation direction of the sheet and generates a test pattern scanned image. An ejection malfunction determination unit determines densities at at least two secondary-scanning-directional positions at a primary-scanning-directional position corresponding to each nozzle in the test pattern scanned image, and determines whether the nozzle is an ejection malfunction nozzle or not on the basis of the determined densities. Here, a slant angle of the sheet is set such that a primary-scanning-directional distance between two positions in the test pattern image corresponding to the two secondary-scanning-directional positions is larger than an arrangement interval of sensor pixels in the sensor chip.

Abstract: An image reading portion includes a light emitting portion and a plurality of photoelectric conversion elements. The light emitting portion emits detection light to a target area extending over a surface of a conveying belt and a pair of off-belt areas outside the conveying belt in a width direction. The image reading portion outputs a plurality of pixel data items. A reference member forms a pair of boundary lines by the difference in reflectance of the detection light at a pair of reference positions in the pair of off-belt areas. A calibration portion identifies data items corresponding to the pair of boundary lines in the plurality of pixel data items obtained by the image reading portion so as to correct reference position data representing a correspondence relationship between the plurality of pixel data items and positions in the width direction.

Abstract: An image forming apparatus includes a print device, a first backend communication portion, a second backend communication portion, and an inquiry management portion. The inquiry management portion transmits, when determining that transmission of a permission response is possible, the permission response to a digital frontend via the first backend communication portion. The second backend communication portion receives print data from the digital frontend. The print device executes print processing that is based on the print data when the print data is received from the digital frontend by the second backend communication portion.

Abstract: An image forming apparatus includes a print device, a first backend communication portion, a second backend communication portion, and an inquiry management portion. The inquiry management portion transmits, when determining that transmission of a permission response is possible, the permission response to a digital frontend via the first backend communication portion. The second backend communication portion receives print data from the digital frontend. The print device executes print processing that is based on the print data when the print data is received from the digital frontend by the second backend communication portion.

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: An image forming apparatus includes a transportation belt, a print engine, and an ejection timing control unit. The transportation belt transports a print sheet. The print engine ejects ink onto the print sheet. The ejection timing control unit adjusts an ink ejection timing of the print engine. The transportation belt includes a flushing opening part. The print engine repeatedly performs ink flushing to the flushing opening part at predetermined timings. Further the ejection timing control unit derives an adjustment amount for the ink ejection timing of the print engine on the basis of: a number of the ink ejection timings in a period from a previous flushing time to a current flushing time, a distance from the flushing opening part for the flushing at the previous flushing time to the flushing opening part for the flushing at the current flushing time, and a print resolution.

Abstract: A print engine physically prints an image to be printed on a print sheet in an inkjet manner. A correction processing unit performs a correction process for a specific image column range corresponding to a configuration or a status of the print engine. Further, when performing duplex printing on first and second surfaces of the print sheet, the correction processing unit performs an image shrinking process for an image to be printed on the second surface in accordance with shrinking the print sheet due to ink ejection to the first surface, and Furthermore, the correction processing unit selects an image column range other than the specific image column range in the image to be printed on the second surface as a target image column range for which the image shrinking process should be performed.

Abstract: An image forming apparatus includes a transportation belt, a print engine, and an ejection timing control unit. The transportation belt transports a print sheet. The print engine ejects ink onto the print sheet. The ejection timing control unit adjusts an ink ejection timing of the print engine. The transportation belt includes a flushing opening part. The print engine repeatedly performs ink flushing to the flushing opening part at predetermined timings. Further the ejection timing control unit derives an adjustment amount for the ink ejection timing of the print engine on the basis of: a number of the ink ejection timings in a period from a previous flushing time to a current flushing time, a distance from the flushing opening part for the flushing at the previous flushing time to the flushing opening part for the flushing at the current flushing time, and a print resolution.

Abstract: An image forming apparatus includes a display panel, a sheet conveying passage, a reading unit, a light source, a chassis, and a controller. The reading unit includes a light transmitting plate and a conveying image sensor. The conveying image sensor reads a conveyed sheet, which is a sheet to print on. The chassis has a cleaning hole in which to insert a cleaning rod for rubbing the light-transmitting plate. In a maintenance mode, the controller turns on the light source, and makes the display panel display a graph showing the pixel values of the pixels included in conveyed-and-read image data acquired by reading with the conveying image sensor.

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: An image forming apparatus includes a conveyance part, an image forming part, a sheet detection sensor, a sensor unit, and a controller. The sheet detection sensor, in which a plurality of sensor blocks each with a plurality of sensor elements mounted thereon at specified intervals are arrayed in a sheet width direction, detects an edge position in the sheet width direction on a basis of scanning image data formed by reading of the sheet. The controller is enabled to execute a calibration of inserting, into the scanning image data, interpolation pixels for compensating an error between an edge position detected by the scanning image data and an actual edge position.

Abstract: An image forming apparatus includes a display panel, a sheet conveying passage, a reading unit, a light source, a chassis, and a controller. The reading unit includes a light transmitting plate and a conveying image sensor. The conveying image sensor reads a conveyed sheet, which is a sheet to print on. The chassis has a cleaning hole in which to insert a cleaning rod for rubbing the light-transmitting plate. In a maintenance mode, the controller turns on the light source, and makes the display panel display a graph showing the pixel values of the pixels included in conveyed-and-read image data acquired by reading with the conveying image sensor.

Abstract: A first storage portion stores, in advance, first reference voltage values respectively for ink ejection portions, the first reference voltage values corresponding to a predetermined first image density value. A second storage portion stores, in advance, voltage values that are different from each other, and measurement values that indicate image densities respectively corresponding to the voltage values. A voltage value calculating portion, at a predetermined change timing for changing image density, calculates second reference voltage values respectively for the ink ejection portions based on the voltage values and the measurement values, the second reference voltage values corresponding to a second image density value that is different from the first image density value. A voltage switching portion switches driving voltages that are applied to the ink ejection portions, from driving voltages having the first reference voltage values to driving voltages having the second reference voltage values.

Abstract: A data acquiring portion acquires a plurality of pieces of second data having different levels depending on amounts of light incident on the light reception portions upon reception of a specific linear light having a specific amount of light. A level acquiring portion acquires a maximum level and a minimum level from among the levels of the plurality of pieces of second data. A characteristic data storage portion preliminarily stores characteristic data that indicates levels of the plurality of pieces of second data. A light amount deriving portion executes a light amount deriving process to derive a set light amount of the linear light based on a threshold, the maximum level, the minimum level, and the characteristic data. A second light emission control portion causes the light emission portion to emit linear light having the set light amount.

Abstract: An image forming apparatus includes a conveyance part, an image forming part, a sheet detection sensor, a sensor unit, and a controller. The sheet detection sensor, in which a plurality of sensor blocks each with a plurality of sensor elements mounted thereon at specified intervals are arrayed in a sheet width direction, detects an edge position in the sheet width direction on a basis of scanning image data formed by reading of the sheet. The controller is enabled to execute a calibration of inserting, into the scanning image data, interpolation pixels for compensating an error between an edge position detected by the scanning image data and an actual edge position.

Abstract: A data acquiring portion acquires a plurality of pieces of second data having different levels depending on amounts of light incident on the light reception portions upon reception of a specific linear light having a specific amount of light. A level acquiring portion acquires a maximum level and a minimum level from among the levels of the plurality of pieces of second data. A characteristic data storage portion preliminarily stores characteristic data that indicates levels of the plurality of pieces of second data. A light amount deriving portion executes a light amount deriving process to derive a set light amount of the linear light based on a threshold, the maximum level, the minimum level, and the characteristic data. A second light emission control portion causes the light emission portion to emit linear light having the set light amount.

Abstract: A first storage portion stores, in advance, first reference voltage values respectively for ink ejection portions, the first reference voltage values corresponding to a predetermined first image density value. A second storage portion stores, in advance, voltage values that are different from each other, and measurement values that indicate image densities respectively corresponding to the voltage values. A voltage value calculating portion, at a predetermined change timing for changing image density, calculates second reference voltage values respectively for the ink ejection portions based on the voltage values and the measurement values, the second reference voltage values corresponding to a second image density value that is different from the first image density value. A voltage switching portion switches driving voltages that are applied to the ink ejection portions, from driving voltages having the first reference voltage values to driving voltages having the second reference voltage values.

Abstract: An inkjet recording apparatus includes a plurality of nozzles, storage, a first reading section, a first computing section, a selection section, and a controller. The storage stores first information and first pattern image data representing a first pattern image. The first reading section scans a sheet to generate sheet data. The first computing section computes positions of both edge portions of the sheet in a main scanning direction based on the sheet data. The selection section selects a plurality of used nozzles. The controller directs the used nozzles to form a second pattern image on the sheet.