Abstract: A positional deviation correction pattern includes a first and second pattern image portions adjacent in a sub-scanning direction at the same position in a main-scanning direction, with the same width in the main-scanning direction. Each image portion includes a first side extending in the sub-scanning direction, a second side continuing from one end of the first side and extending in a direction intersecting the sub-scanning direction, and a third side continuing from the other end and extending in a direction intersecting both the sub-scanning direction and the second side. The second sides have the same inclination angle to a virtual line parallel to the main-scanning direction. The third sides have the same inclination angle to the virtual line. A length of one image portion in the sub-scanning direction gradually increases from one end to the other end in the main-scanning direction, a length of the other image portion gradually decreases.

Abstract: An image forming apparatus includes an image bearer to bear a latent electrostatic image thereon, a developing device to supply a development agent to the latent electrostatic image to obtain a visible image, a transfer roller to contact the image bearer to transfer the visible image to a recording medium, a replenishing device to replenish the developing device with the development agent when a density value read from a density detection pattern formed on the image bearer by the developing device is equal to or less than a threshold, a processing device to conduct a predetermined processing to reduce attachment of the development agent to the transfer roller, and a control device to control the number of times the predetermined processing is performed or processing time in performing the predetermined processing for the processing device, based on whether there is replenishment of the development agent to the developing device.

Abstract: An image forming apparatus includes an image bearer to bear a latent electrostatic image thereon, a developing device to supply a development agent to the latent electrostatic image to obtain a visible image, a transfer roller to contact the image bearer to transfer the visible image to a recording medium, a replenishing device to replenish the developing device with the development agent when a density value read from a density detection pattern formed on the image bearer by the developing device is equal to or less than a threshold, a processing device to conduct a predetermined processing to reduce attachment of the development agent to the transfer roller, and a control device to control the number of times the predetermined processing is performed or processing time in performing the predetermined processing for the processing device, based on whether there is replenishment of the development agent to the developing device.

Abstract: A positional deviation correction pattern includes a first and second pattern image portions adjacent in a sub-scanning direction at the same position in a main-scanning direction, with the same width in the main-scanning direction. Each image portion includes a first side extending in the sub-scanning direction, a second side continuing from one end of the first side and extending in a direction intersecting the sub-scanning direction, and a third side continuing from the other end and extending in a direction intersecting both the sub-scanning direction and the second side. The second sides have the same inclination angle to a virtual line parallel to the main-scanning direction. The third sides have the same inclination angle to the virtual line. A length of one image portion in the sub-scanning direction gradually increases from one end to the other end in the main-scanning direction, a length of the other image portion gradually decreases.

Abstract: An image forming apparatus including a main carriage to move and scan in a main scanning direction, a sub-carriage connectable to the main carriage to move and scan in the main scanning direction together with the main carriage, a positioning guide provided on one of the main carriage and the sub-carriage, and a position detector provided on the other one of the main carriage and the sub-carriage. The position detector reads the positioning guide as the main carriage and the sub-carriage connect to each other to detect relative positions of the main carriage and the sub-carriage.

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 includes a base member where a plurality of recording heads is provided, the recording heads being configured to jet liquid drops onto a recording medium; a carriage configured to elevatably support the base member; and an elevating part configured to elevate the base member relative to the carriage, wherein the elevating part is a plurality of slide cam members provided movably in a horizontal direction.

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.

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 main carriage to move and scan in a main scanning direction, a sub-carriage connectable to the main carriage to move and scan in the main scanning direction together with the main carriage, a positioning guide provided on one of the main carriage and the sub-carriage, and a position detector provided on the other one of the main carriage and the sub-carriage. The position detector reads the positioning guide as the main carriage and the sub-carriage connect to each other to detect relative positions of the main carriage and the sub-carriage.

Abstract: An image forming apparatus includes a base member where a plurality of recording heads is provided, the recording heads being configured to jet liquid drops onto a recording medium; a carriage configured to elevatably support the base member; and an elevating part configured to elevate the base member relative to the carriage, wherein the elevating part is a plurality of slide cam members provided movably in a horizontal direction.