Abstract: An image forming apparatus includes a latent image carrier, a charging device, a latent image forming device, a developing device, a transfer device, a toner amount detector, and a control circuit to execute an imaging condition determination process. The control circuit obtains a linear approximation formula of a developing potential and an amount of toner according to an exposure potential of the patch pattern and a detected amount of toner to calculate a developing gamma and a developing start voltage according to a gradient of the linear approximation formula, determines target charging potential, exposure potential and developing bias according to the developing gamma and the developing start voltage, determines an amount of a background potential to be corrected according to a difference between the developing start voltage and a target developing start voltage obtained according to environmental information, and corrects the target charging potential.

Abstract: The image forming apparatus includes a process unit, a latent image writer, a power source, and a controller. The process unit is detachably attachable relative to the image forming apparatus and includes, as a single integrated unit, a latent image bearing member to bear a latent image on a surface thereof, a charging device to charge the surface of the latent image bearing member, and a development device to develop the latent image with toner. The controller causes the power source to output a charging bias at a predetermined target level supplied to the charging device. The process unit includes a first storage device to store correction information for calculating the predetermined target level of the charging bias in accordance with a combination of the latent image bearing member and the charging device. The controller corrects the predetermined target level based on the correction information in the first storage device.

Abstract: An image forming apparatus includes a driving device, a transfer body, a toner detector, an error notification device, and a controller. The toner detector detects, at a preparation running and while the driving device drives a latent image bearer, one of a toner adhesion amount at a background portion of the latent image bearer and a toner adhesion amount at a background corresponding region of a transfer body. The error notification device notifies a user of an error with the toner adhesion being equal to or greater than a predetermined threshold value. The driving device stops only a developer bearer after driving both the latent image bearer and the developer bearer at the preparation running, but before a trailing edge of a detection target region of one of the background portion of the latent image bearer and the background corresponding region advances to an opposite position to the toner detector.

Abstract: An image forming apparatus includes a latent image carrier to carry a latent image on a surface thereof, a developing device to develop the latent image with toner to form a toner image on the surface of the latent image carrier, a transfer unit to transfer the toner image onto a recording medium, and a controller. The controller executes an image density adjustment control of adjusting a developing bias to obtain a target image density. The controller further executes a forced toner consumption control of forcibly consuming the toner contained in the developing device by attaching the toner to the latent image carrier to form a toner pattern on the surface of the latent image carrier. The controller executes the forced toner consumption control to forcibly consume a smaller amount of toner in response to a higher developing bias as adjusted by the image density adjustment control.

Abstract: The image forming apparatus includes a process unit, a latent image writer, a power source, and a controller. The process unit is detachably attachable relative to the image forming apparatus and includes, as a single integrated unit, a latent image bearing member to bear a latent image on a surface thereof, a charging device to charge the surface of the latent image bearing member, and a development device to develop the latent image with toner. The controller causes the power source to output a charging bias at a predetermined target level supplied to the charging device. The process unit includes a first storage device to store correction information for calculating the predetermined target level of the charging bias in accordance with a combination of the latent image bearing member and the charging device. The controller corrects the predetermined target level based on the correction information in the first storage device.

Abstract: An image forming apparatus includes a latent image bearing member, a charging unit, a charging power source, a latent image writing unit, a development unit, a transfer unit, a toner detector, and a controller. The controller causes a background fog pattern to be formed on a surface of the latent image bearing member. In addition to the background fog pattern, the controller causes a latent image to be developed to form a toner image used for position identification on the surface of the latent image bearing member. The controller identifies a time when the toner image used for position identification has entered a detection range of the toner detector based on a change in outputs of the toner detector to determine a time when each of sections of the background fog pattern enters the detection range based on the identified time.

Abstract: An image forming apparatus includes a latent image carrier, a charging device, a latent image forming device, a developing device, a transfer device, a toner amount detector, and a control circuit to execute an imaging condition determination process. The control circuit obtains a linear approximation formula of a developing potential and an amount of toner according to an exposure potential of the patch pattern and a detected amount of toner to calculate a developing gamma and a developing start voltage according to a gradient of the linear approximation formula, determines target charging potential, exposure potential and developing bias according to the developing gamma and the developing start voltage, determines an amount of a background potential to be corrected according to a difference between the developing start voltage and a target developing start voltage obtained according to environmental information, and corrects the target charging potential.

Abstract: An image forming apparatus includes a latent image carrier to carry a latent image on a surface thereof, a developing device to develop the latent image with toner to form a toner image on the surface of the latent image carrier, a transfer unit to transfer the toner image onto a recording medium, and a controller. The controller executes an image density adjustment control of adjusting a developing bias to obtain a target image density. The controller further executes a forced toner consumption control of forcibly consuming the toner contained in the developing device by attaching the toner to the latent image carrier to form a toner pattern on the surface of the latent image carrier. The controller executes the forced toner consumption control to forcibly consume a smaller amount of toner in response to a higher developing bias as adjusted by the image density adjustment control.

Abstract: An image forming apparatus including a first carriage having a first recording head to eject black liquid droplets, a second carriage having a second recording head to eject color liquid droplets and separatably dockable with the first carriage, a position detector to detect a position of the second carriage relative to the first carriage in a state in which the first and second carriages are docked with each other, and a landing position corrector to correct landing positions of liquid droplets ejected from at least one of the first and second recording heads. The landing position corrector holds the position of the second carriage obtained by the position detector as a reference position and adjusts a correction amount for correcting the landing positions based on an amount of shift between the reference position and a present position of the second carriage docked with the first carriage.

Abstract: An image forming apparatus including a first carriage having a recording head that ejects black liquid droplets and is movable in a main scanning direction and a second carriage having a recording head that ejects color liquid droplets and is detachably attachable to the first carriage within a scanning range of the first carriage in the main scanning direction. The second carriage when attached to the first carriage is movable in the main scanning direction together with the first carriage. Attachment and detachment of the second carriage to and from the first carriage are performed based on a predetermined reference position of the first carriage in the main scanning direction.

Abstract: An image forming apparatus including a first carriage having at least two first recording heads, a second carriage separatably dockable with the first carriage, a pattern forming unit to control the at least two first recording heads to form on a recording medium adjustment patterns for correcting a shift in landing positions of liquid droplets ejected from the at least two first recording heads, a pattern detector provided to the first carriage to read the adjustment patterns, and a landing position corrector to correct the shift in the landing positions of the liquid droplets based on a result obtained by the pattern detector. The at least two first recording heads form multiple rows of the adjustment patterns, and the pattern detector successively reads at least two rows of the multiple rows of the adjustment patterns without docking and separation of the first and second carriages.

Abstract: An image forming apparatus including a first carriage having a recording head that ejects black liquid droplets and is movable in a main scanning direction, a second carriage having a recording head that ejects color liquid droplets and is detachably attachable to the first carriage to move in the main scanning direction together with the first carriage while attached to the first carriage, and a cap member that caps the recording head of the second carriage while the first carriage is moving with the second carriage separated from the first carriage. Attachment and detachment of the second carriage to and from the first carriage are performed within a scanning range through which the first carriage is movable.

Abstract: An image forming apparatus including a first carriage having a first recording head and a first lifting/lowering unit, a second carriage having a second recording head and a second lifting/lowering unit, a drive source, a drive coupling unit provided to the drive source, a first coupling unit, a second coupling unit, a docking/separation unit that docks and separates the first and second carriages, and an accommodation/coupling unit. A first end of the second coupling unit is coupled to the drive coupling unit, and the accommodation/coupling unit couples the first coupling unit to a second end of the second coupling unit and accommodates the first coupling unit within the first carriage to uncouple the first coupling unit from the second end of the second coupling unit. Accommodation and coupling of the first coupling unit are performed in conjunction with docking and separation of the first and second carriages.

Abstract: An image forming apparatus including a first carriage movable in a main scanning direction, a second carriage separatably dockable with the first carriage, a first positioning unit to position the second carriage relative to the first carriage in a sub-scanning direction, a second positioning unit to position the second carriage relative to the first carriage in a rotary direction, and a third positioning unit to position the second carriage relative to the first carriage in the main scanning direction. The first positioning unit includes a reference shaft and notched positioning members to engage the reference shaft. The second positioning unit contacts one of the first and second carriages in the rotary direction upon docking of the first and second carriages. The third positioning unit includes a positioning member, parallel grooved members in the sub-scanning direction, and parallel shafts extending in the sub-scanning direction to engage the grooved members.

Abstract: An image forming apparatus including a first carriage having at least two first recording heads, a second carriage separatably dockable with the first carriage, a pattern forming unit to control the at least two first recording heads to form on a recording medium adjustment patterns for correcting a shift in landing positions of liquid droplets ejected from the at least two first recording heads, a pattern detector provided to the first carriage to read the adjustment patterns, and a landing position corrector to correct the shift in the landing positions of the liquid droplets based on a result obtained by the pattern detector. The at least two first recording heads form multiple rows of the adjustment patterns, and the pattern detector successively reads at least two rows of the multiple rows of the adjustment patterns without docking and separation of the first and second carriages.

Abstract: An image forming apparatus including a first carriage movable in a main scanning direction, a second carriage separatably dockable with the first carriage, a first positioning unit to position the second carriage relative to the first carriage in a sub-scanning direction, a second positioning unit to position the second carriage relative to the first carriage in a rotary direction, and a third positioning unit to position the second carriage relative to the first carriage in the main scanning direction. The first positioning unit includes a reference shaft and notched positioning members to engage the reference shaft. The second positioning unit contacts one of the first and second carriages in the rotary direction upon docking of the first and second carriages. The third positioning unit includes a positioning member, parallel grooved members in the sub-scanning direction, and parallel shafts extending in the sub-scanning direction to engage the grooved members.

Abstract: An image forming apparatus including a first carriage having a first recording head to eject black liquid droplets, a second carriage having a second recording head to eject color liquid droplets and separatably dockable with the first carriage, a position detector to detect a position of the second carriage relative to the first carriage in a state in which the first and second carriages are docked with each other, and a landing position corrector to correct landing positions of liquid droplets ejected from at least one of the first and second recording heads. The landing position corrector holds the position of the second carriage obtained by the position detector as a reference position and adjusts a correction amount for correcting the landing positions based on an amount of shift between the reference position and a present position of the second carriage docked with the first carriage.

Abstract: An image forming apparatus including a first carriage having a first recording head and a first lifting/lowering unit, a second carriage having a second recording head and a second lifting/lowering unit, a drive source, a drive coupling unit provided to the drive source, a first coupling unit, a second coupling unit, a docking/separation unit that docks and separates the first and second carriages, and an accommodation/coupling unit. A first end of the second coupling unit is coupled to the drive coupling unit, and the accommodation/coupling unit couples the first coupling unit to a second end of the second coupling unit and accommodates the first coupling unit within the first carriage to uncouple the first coupling unit from the second end of the second coupling unit. Accommodation and coupling of the first coupling unit are performed in conjunction with docking and separation of the first and second carriages.

Abstract: An image forming apparatus including a first carriage having a recording head that ejects black liquid droplets and is movable in a main scanning direction, a second carriage having a recording head that ejects color liquid droplets and is detachably attachable to the first carriage to move in the main scanning direction together with the first carriage while attached to the first carriage, and a cap member that caps the recording head of the second carriage while the first carriage is moving with the second carriage separated from the first carriage. Attachment and detachment of the second carriage to and from the first carriage are performed within a scanning range through which the first carriage is movable.