Abstract: An image forming apparatus is provided with a carriage in which recording heads having nozzles for ejecting liquid droplets are mounted and is configured to form an image on a recording medium being transported. The image forming apparatus includes a pattern forming unit that forms an impact position displacement adjustment pattern formed of plural independent liquid droplets on a water repellent member; a reading unit that includes a light emitting unit for emitting light onto the adjustment pattern and a light receiving unit for receiving specular reflection light from the adjustment pattern; and an impact position correcting unit that corrects an impact position of a liquid droplet to be ejected from the recording head based on a read result by the reading unit. The reading unit is disposed on the carriage and is arranged close to the side of a guide member that guides movement of the carriage.

Abstract: In a carriage of a liquid drop discharging device, an encoder sensor is arranged to read slits on a linear scale at a slit reading position. The carriage includes a stain detection part that detects a stain on the linear scale based on position information output from the encoder sensor. An encoder sensor moving part moves the encoder sensor from the slit reading position in a width direction of the linear scale. An encoder sensor movement control part controls movement of the encoder sensor from the slit read position by the encoder sensor moving part based on stain information output from the stain detection part.

Abstract: A disclosed liquid-jet device includes a liquid-jet head configured to jet liquid droplets; a pattern formation control unit configured to control the liquid-jet head and thereby to form a test pattern composed of separate liquid droplets on a water-repellent part; a detecting unit including a light-emitting element configured to illuminate the test pattern on the water-repellent part and a light-receiving element configured to receive specularly reflected light from the illuminated test pattern and to output a detection signal proportional to the received specularly reflected light; and a landing position adjusting unit configured to adjust landing positions of the liquid droplets based on the detection signal from the light-receiving element.

Abstract: A disclosed transfer apparatus includes an endless belt to transfer a recording member by attaching the recording member on a surface thereof by an electrostatic force; a driving device to rotate the endless belt; and a holding device to temporarily hold the recording member to hinder a movement thereof caused by a movement of the endless belt rotated by the driving device so that a part of the recording member slides on the surface of the endless belt.

Abstract: An image forming apparatus includes a recording head, a water-repellent transfer belt, a pattern formation controller, a read unit, and a detection unit. The recording head has a plurality of nozzles aligned in a given direction, and ejects droplets of a liquid therefrom. The pattern formation controller directs each of the plurality of nozzles to eject the liquid to form a detection pattern on the transfer belt. The detection pattern has multiple droplets ejected from each of the plurality of nozzles sequentially arranged and spaced apart from each other both in the given direction and in a direction orthogonal to the given direction. The read unit includes a light emitting element and a light receiving element, and reads the detection pattern to output a read result. The detection unit detects a defective nozzle according to the read result.

Abstract: A side wall surface of a carriage is disclosed with two first projection parts and a second projection part that define the inclination of a reflective optical sensor in its vertical direction. The two first projection parts are arranged at the same height position with a detection surface as a reference, and the second projection part is arranged at a position higher than the first projection parts with the detection surface as the reference. The second projection part has a first part higher in position from the side wall surface of the carriage than the first projection parts and has a second part lower in position than the first part. The second part has a screw hole into which a clamping member for fixing the reflective optical sensor to the second part is tightened.

Abstract: An adjustment pattern, which is composed of a reference pattern made of plural independent liquid droplets and a pattern to be measured made of plural independent liquid droplets ejected under an ejection condition different from the reference pattern, is formed on a water-repellent conveying belt. Then, light is applied to the adjustment pattern to receive the regular reflection light from the adjustment pattern, so that the adjustment pattern is scanned. The distance between the respective patterns is measured based on the measured result. Finally, liquid droplet ejection timing of the recording head is corrected based on the result thus measured.

Abstract: A disclosed image forming apparatus includes a recording head configured to jet liquid droplets; a pattern forming unit configured to form, on a water-repellent surface of a water-repellent sheet member, an adjustment pattern used for correcting shifts in landing positions of the liquid droplets, wherein the adjustment pattern includes plural liquid droplets that are separated from each other, and the water-repellent surface having a water-repellent property is formed on at least a part of a surface of the water-repellent sheet member; a reading unit including a light emitting unit configured to irradiate light onto the adjustment pattern and a light receiving unit configured to receive specular reflection light from the adjustment pattern; and a landing position correction unit configured to correct, based on a reading result obtained by the reading unit, the shifts in the landing positions of the liquid droplets that are jetted from the recording head.

Abstract: A disclosed image forming apparatus includes a carriage having a head for jetting droplets; a pattern forming unit configured to form, on a belt, a pattern used for detecting displacement of landing positions of the droplets; a reading unit configured to scan the belt before the pattern formation to output a first result, and scan the pattern to output a second result; a correcting unit configured to correct the displacement based on the second result; a frequency analyzing unit configured to calculate frequencies of the belt and amplitudes of respective frequency components based on the first result; and a peak frequency calculating unit configured to calculate peak frequencies of the belt based on the frequencies of the belt and the amplitudes of the frequency components, the peak frequencies being frequency components whose amplitude exceeds a predetermined level. The pattern is formed at a frequency different from the peak frequencies.

Abstract: An image forming apparatus includes a carriage carrying a recording head configured to discharge a droplet. A landing position error detecting pattern is formed on a pattern forming member. Based on a result of reading the landing position error detecting pattern, a landing position error of the droplet discharged by the recording head is corrected. Either a first pattern or a second pattern is selected as the landing position error detecting pattern, depending on a surface condition of the pattern forming member. The first pattern produces a relatively small amount of specular reflection compared with diffused reflection, while the second pattern produces a relatively large amount of specular reflection compared with diffused reflection, upon irradiation with light.

Abstract: In a carriage of a liquid drop discharging device, an encoder sensor is arranged to read slits on a linear scale at a slit reading position. The carriage includes a stain detection part that detects a stain on the linear scale based on position information output from the encoder sensor. An encoder sensor moving part moves the encoder sensor from the slit reading position in a width direction of the linear scale. An encoder sensor movement control part controls movement of the encoder sensor from the slit read position by the encoder sensor moving part based on stain information output from the stain detection part.

Abstract: A disclosed transfer apparatus includes an endless belt to transfer a recording member by attaching the recording member on a surface thereof by an electrostatic force; a driving device to rotate the endless belt; and a holding device to temporarily hold the recording member to hinder a movement thereof caused by a movement of the endless belt rotated by the driving device so that a part of the recording member slides on the surface of the endless belt.

Abstract: A disclosed image forming apparatus includes a carriage on which a recording head is mounted that has a nozzle array where plural nozzles for ejecting droplets are arranged, the carriage being configured to be moved in a direction orthogonal to a nozzle arrangement direction; a transport belt facing the recording head and configured to transport a sheet; a print pattern forming unit configured to form a print pattern on the transport belt by causing at least the nozzles at opposing ends of the nozzle array to eject the droplets onto the transport belt while stopping the carriage; a reading unit configured to read the print pattern; a measuring unit configured to measure print positions of plural points of the print pattern in a direction orthogonal to the nozzle arrangement direction; and a detecting unit configured to detect an inclination of the recording head.

Abstract: An image forming apparatus includes a carriage carrying a recording head configured to discharge a droplet. A landing position error detecting pattern is formed on a pattern forming member. Based on a result of reading the landing position error detecting pattern, a landing position error of the droplet discharged by the recording head is corrected. Either a first pattern or a second pattern is selected as the landing position error detecting pattern, depending on a surface condition of the pattern forming member. The first pattern produces a relatively small amount of specular reflection compared with diffused reflection, while the second pattern produces a relatively large amount of specular reflection compared with diffused reflection, upon irradiation with light.

Abstract: A disclosed image forming apparatus includes a carriage having a head for jetting droplets; a pattern forming unit configured to form, on a belt, a pattern used for detecting displacement of landing positions of the droplets; a reading unit configured to scan the belt before the pattern formation to output a first result, and scan the pattern to output a second result; a correcting unit configured to correct the displacement based on the second result; a frequency analyzing unit configured to calculate frequencies of the belt and amplitudes of respective frequency components based on the first result; and a peak frequency calculating unit configured to calculate peak frequencies of the belt based on the frequencies of the belt and the amplitudes of the frequency components, the peak frequencies being frequency components whose amplitude exceeds a predetermined level. The pattern is formed at a frequency different from the peak frequencies.

Abstract: A side wall surface of a carriage is disclosed with two first projection parts and a second projection part that define the inclination of a reflective optical sensor in its vertical direction. The two first projection parts are arranged at the same height position with a detection surface as a reference, and the second projection part is arranged at a position higher than the first projection parts with the detection surface as the reference. The second projection part has a first part higher in position from the side wall surface of the carriage than the first projection parts and has a second part lower in position than the first part. The second part has a screw hole into which a clamping member for fixing the reflective optical sensor to the second part is tightened.

Abstract: An image forming apparatus includes a recording head, a water-repellent transfer belt, a pattern formation controller, a read unit, and a detection unit. The recording head has a plurality of nozzles aligned in a given direction, and ejects droplets of a liquid therefrom. The pattern formation controller directs each of the plurality of nozzles to eject the liquid to form a detection pattern on the transfer belt. The detection pattern has multiple droplets ejected from each of the plurality of nozzles sequentially arranged and spaced apart from each other both in the given direction and in a direction orthogonal to the given direction. The read unit includes a light emitting element and a light receiving element, and reads the detection pattern to output a read result. The detection unit detects a defective nozzle according to the read result.

Abstract: A disclosed image forming apparatus for forming an image on a recording medium being conveyed includes: a recording head discharging droplets; a pattern forming unit forming an adjustment pattern for detecting displacement of landing positions of droplets on a water-repellent member, the adjustment pattern including a minimum block pattern for each detection item and being formed with plural droplets independent of one another; a reading unit including a light emitting unit projecting a light onto the adjustment pattern and a light receiving unit receiving a regular reflection light from the adjustment pattern; and a landing position correcting unit correcting the landing positions of the droplets discharged from the recording head based on a result of reading by the reading unit.

Abstract: An image forming apparatus is provided with a carriage in which recording heads having nozzles for ejecting liquid droplets are mounted and is configured to form an image on a recording medium being transported. The image forming apparatus includes a pattern forming unit that forms an impact position displacement adjustment pattern formed of plural independent liquid droplets on a water repellent member; a reading unit that includes a light emitting unit for emitting light onto the adjustment pattern and a light receiving unit for receiving specular reflection light from the adjustment pattern; and an impact position correcting unit that corrects an impact position of a liquid droplet to be ejected from the recording head based on a read result by the reading unit. The reading unit is disposed on the carriage and is arranged close to the side of a guide member that guides movement of the carriage.

Abstract: A disclosed liquid-jet device includes a liquid-jet head configured to jet liquid droplets; a pattern formation control unit configured to control the liquid-jet head and thereby to form a test pattern composed of separate liquid droplets on a water-repellent part; a detecting unit including a light-emitting element configured to illuminate the test pattern on the water-repellent part and a light-receiving element configured to receive specularly reflected light from the illuminated test pattern and to output a detection signal proportional to the received specularly reflected light; and a landing position adjusting unit configured to adjust landing positions of the liquid droplets based on the detection signal from the light-receiving element.