Abstract: A sheet conveyor includes: a holder that detachably holds a sheet roll; a rotation measuring device that measures a rotation amount of the sheet roll; a conveyance roller that conveys a sheet pulled out from the sheet roll held by the holder; a tensioner that is provided between the holder and the conveyance roller and that contacts with the sheet pulled out from the sheet roll toward the conveyance roller; a position detector that detects a position of the tensioner; a motor that generates driving force for rotating the conveyance roller; and a controller that controls the motor. The controller estimates a diameter of the sheet roll based on a conveyance amount of the sheet caused by rotation of the conveyance roller, a rotation amount of the sheet roll measured by the rotation measuring device, and a position of the tensioner detected by the position detector.

Abstract: A sheet conveyor includes: a holder that detachably holds a sheet roll; a rotation measuring device that measures a rotation amount of the sheet roll; a conveyance roller that conveys a sheet pulled out from the sheet roll held by the holder; a tensioner that is provided between the holder and the conveyance roller and that contacts with the sheet pulled out from the sheet roll toward the conveyance roller; a position detector that detects a position of the tensioner; a motor that generates driving force for rotating the conveyance roller; and a controller that controls the motor. The controller estimates a diameter of the sheet roll based on a conveyance amount of the sheet caused by rotation of the conveyance roller, a rotation amount of the sheet roll measured by the rotation measuring device, and a position of the tensioner detected by the position detector.

Abstract: A sheet conveyor includes: a holder that detachably holds a sheet roll; a conveyance roller that conveys, by rotation, a sheet pulled out from the sheet roll; a first motor that rotates the conveyance roller; a second motor that rotates the sheet roll along with the conveyance of the sheet; a tension estimator that estimates tension of the sheet conveyed by the rotation of the conveyance roller; a measuring device that measures a physical quantity related to rotary motion of the conveyance roller; and a controller. The controller estimates acceleration torque of the second motor required for rotating the sheet roll depending on acceleration of the conveyance roller, based on rotation acceleration of the conveyance roller specified by the physical quantity measured by the measuring device, and calculates a feedforward control input for the second motor based on the acceleration torque estimated.

Abstract: A controlling device may perform an image process on specific image data so as to generate processed image data, supply the processed image data to the print performing unit and perform, in order to compensate variability of discharging amount of ink droplets discharged from the plurality of nozzles, a specific process on a target pixel within target image data using correction data for a target nozzle which forms a dot at a position on a print medium corresponding to the target pixel. The correction data may be data acquired using two or more sets of characteristic data corresponding to two or more nozzles of the plurality of nozzles. The two or more nozzles may include the target nozzle and a specific nozzle. The specific nozzle may be to form a raster near a target raster formed on the print medium by the target nozzle.

Abstract: In a printing device, a first control unit prints, by a first print method, an image on a first region of a recording sheet in a first state in which a recording sheet is clamped by both an upstream and downstream clamping portions. A second control unit prints, by a second print method, an image on a second region of the recording sheet in a second state in which the recording sheet is clamped either one of the upstream and downstream clamping portions. A third control unit prints, by a combination of the first and second print methods, an image on a third region of the recording sheet between the first and second regions. When the third control unit prints the image on the third region, a state of the recording sheet is set to be changed from the first state to the second state.

Abstract: In a printing device, the print control processor is configured to perform a print operation in a resolution in which a plurality of raster lines is arranged in a first direction by a line pitch smaller than the prescribed nozzle pitch by using a prescribed print method. The prescribed print method prints the plurality of raster lines arranged in the first direction in a prescribed order. The print control processor is configured to control a scanning portion to convey the recording sheet by a biased conveying distance as a target conveying distance. The biased conveying distance is set, depending on the prescribed print method, to be decreased or increased from a prescribed distance. The prescribed distance is an ideal value that achieves the resolution in which the plurality of raster lines is uniformly arranged in the first direction by the line pitch.

Abstract: A control device includes an execution unit, a determining unit, and a setting unit. The execution unit controls a printing unit to execute a multi-pass printing for a predetermined partial area of printing medium by executing sub scans and a prescribed number of times of main scans. In the main scan, a print head of the printing unit forms dots on the recording medium while being conveyed in a main scanning direction. In the sub-scan, the printing medium is conveyed in a sub-scanning direction. The determining unit determines an acceptable range based on an actual conveyance error in the sub-scanning direction. The setting unit sets the prescribed number to N when a representative value of predetermined partial area falls in the acceptable range, and sets the prescribed number to M being an integer greater than N when the representative value does not fall in the acceptable range.

Abstract: In a printing device, includes a print head, a scanning portion, a head drive portion, and a print control processor. The print control processor is configured to function as a property data acquiring unit and a print method selecting unit. The property data acquiring unit is configured to acquire property data with respect to a property of the scan. The print method selecting unit is configured to select, based on the property data, one of a plurality of print methods, each of the plurality of print method printing, in a prescribed order, the plurality of raster lines arranged in the first direction by the line pitch. The prescribed order is specific to each of the plurality of print methods. The print control processor is configured to perform the print operation in the resolution by using the selected one of the plurality of methods.

Abstract: In a printing device, the print control processor is configured to perform a print operation in a resolution in which a plurality of raster lines is arranged in a first direction by a line pitch smaller than the prescribed nozzle pitch by using a prescribed print method. The prescribed print method prints the plurality of raster lines arranged in the first direction in a prescribed order. The print control processor is configured to control a scanning portion to convey the recording sheet by a biased conveying distance as a target conveying distance. The biased conveying distance is set, depending on the prescribed print method, to be decreased or increased from a prescribed distance. The prescribed distance is an ideal value that achieves the resolution in which the plurality of raster lines is uniformly arranged in the first direction by the line pitch.

Abstract: In a printing device, includes a print head, a scanning portion, a head drive portion, and a print control processor. The print control processor is configured to function as a property data acquiring unit and a print method selecting unit. The property data acquiring unit is configured to acquire property data with respect to a property of the scan. The print method selecting unit is configured to select, based on the property data, one of a plurality of print methods, each of the plurality of print method printing, in a prescribed order, the plurality of raster lines arranged in the first direction by the line pitch. The prescribed order is specific to each of the plurality of print methods. The print control processor is configured to perform the print operation in the resolution by using the selected one of the plurality of methods.

Abstract: In a printing device, a first control unit prints, by a first print method, an image on a first region of a recording sheet in a first state in which a recording sheet is clamped by both an upstream and downstream clamping portions. A second control unit prints, by a second print method, an image on a second region of the recording sheet in a second state in which the recording sheet is clamped either one of the upstream and downstream clamping portions. A third control unit prints, by a combination of the first and second print methods, an image on a third region of the recording sheet between the first and second regions. When the third control unit prints the image on the third region, a state of the recording sheet is set to be changed from the first state to the second state.

Abstract: An inkjet head has a plurality of nozzles that are arranged such that distances in a first direction between respective two adjacent nozzles that are adjacent with each other in the first direction are uniform and distances in a second direction orthogonal to the first direction between the respective two adjacent nozzles are nonuniform. The storing unit stores a plurality of dot size determining values corresponding to the plurality of nozzles. Each dot size determining value is defined to determine a size of a dot to be formed by the corresponding nozzle and is determined dependently on a distance in the second direction between the corresponding nozzle and a nozzle adjacent to the corresponding nozzle in the first direction. The determining unit determines a size of a dot to be formed by each nozzle based on the pixel data and the corresponding dot size determining value.

Abstract: A controlling device may perform an image process on specific image data so as to generate processed image data, supply the processed image data to the print performing unit and perform, in order to compensate variability of discharging amount of ink droplets discharged from the plurality of nozzles, a specific process on a target pixel within target image data using correction data for a target nozzle which forms a dot at a position on a print medium corresponding to the target pixel. The correction data may be data acquired using two or more sets of characteristic data corresponding to two or more nozzles of the plurality of nozzles. The two or more nozzles may include the target nozzle and a specific nozzle. The specific nozzle may be to form a raster near a target raster formed on the print medium by the target nozzle.

Abstract: An inkjet head has a plurality of nozzles that are arranged such that distances in a first direction between respective two adjacent nozzles that are adjacent with each other in the first direction are uniform and distances in a second direction orthogonal to the first direction between the respective two adjacent nozzles are nonuniform. The storing unit stores a plurality of dot size determining values corresponding to the plurality of nozzles. Each dot size determining value is defined to determine a size of a dot to be formed by the corresponding nozzle and is determined dependently on a distance in the second direction between the corresponding nozzle and a nozzle adjacent to the corresponding nozzle in the first direction. The determining unit determines a size of a dot to be formed by each nozzle based on the pixel data and the corresponding dot size determining value.