Abstract: An image forming apparatus includes: a plurality of development units having developing-agent carriers which are provided in correspondence to three or more developing agents, and developing electrostatic latent images on surfaces of image carriers to form developing-agent images on the image carriers; and a recovery unit that recovers the developing agent adhering to the developing-agent carrier during non-development operation. The recovery unit is provided for at least the development unit other than the development unit that transfers the developing-agent image first in sequence among the plurality of development units. When one of the plurality of development units performs development by the developing agent whose charge capability is higher than that of the developing agent of the development unit that transfers the developing-agent image later in sequence, the recovery unit starts recovery of the developing agent or performs recovery operation for improving recovery capability of the developing agent.

Abstract: An image forming apparatus includes: a plurality of development units having developing-agent carriers which are provided in correspondence to three or more developing agents, and developing electrostatic latent images on surfaces of image carriers to form developing-agent images on the image carriers; and a recovery unit that recovers the developing agent adhering to the developing-agent carrier during non-development operation. The recovery unit is provided for at least the development unit other than the development unit that transfers the developing-agent image first in sequence among the plurality of development units. When one of the plurality of development units performs development by the developing agent whose charge capability is higher than that of the developing agent of the development unit that transfers the developing-agent image later in sequence, the recovery unit starts recovery of the developing agent or performs recovery operation for improving recovery capability of the developing agent.

Abstract: An image forming apparatus includes: a plurality of development units having developing-agent carriers which are provided in correspondence to three or more developing agents, and developing electrostatic latent images on surfaces of image carriers to form developing-agent images on the image carriers; and a recovery unit that recovers the developing agent adhering to the developing-agent carrier during non-development operation. The recovery unit is provided for at least the development unit other than the development unit that transfers the developing-agent image first in sequence among the plurality of development units. When one of the plurality of development units performs development by the developing agent whose charge capability is higher than that of the developing agent of the development unit that transfers the developing-agent image later in sequence, the recovery unit starts recovery of the developing agent or performs recovery operation for improving recovery capability of the developing agent.

Abstract: A system of printers uses replicable toner boxes, which each has a unique serial number. Each printer determines once the toner box is empty. At this time, the printer registers the serial number of the used toner box in used toner box list in a memory. Each time a toner box is mounted in the printer, the printer reads and compares the serial number of the freshly inserted toner box with the serial numbers in the list in the memory. If the serial number of the presently mounted toner box matches any in the list, this means that the toner box has previously been judged to reach life end, so the printer displays a message that the toner box is not suitable for use in the printer and prevents further printing operations until the toner box is replaced with a new one.

Abstract: During a first rotation of a photoconductor, latent electrostatic images for color correction processing patterns are formed on the photoconductor, and the latent electrostatic images are developed into the color correction processing patterns in each of four colors, and then densities of the patterns on the photoconductor are detected. During a second rotation of the photoconductor, each color of the patterns is recovered back into a developer device.

Abstract: A tandem color laser printer 1 is provided with a photosensitive drum unit 15, a developing unit 14, and a scanning unit 13 for each color. The developing units 14, each including a main developer unit 25 and a toner hopper 24, and the scanning units 13, which irradiate laser beam, are alternately stacked vertically to overlap with each other in the vertical direction. This arrangement eliminates space required when arranging the developing units 14 and scanning units 13 side by side, thereby reducing the footprint of the color laser printer 1.

Abstract: During a first rotation of a photoconductor, latent electrostatic images for color correction processing patterns are formed on the photoconductor, and the latent electrostatic images are developed into the color correction processing patterns in each of four colors, and then densities of the patterns on the photoconductor are detected. During a second rotation of the photoconductor, each color of the patterns is recovered back into a developer device.

Abstract: An image forming apparatus includes: a plurality of development units having developing-agent carriers which are provided in correspondence to three or more developing agents, and developing electrostatic latent images on surfaces of image carriers to form developing-agent images on the image carriers; and a recovery unit that recovers the developing agent adhering to the developing-agent carrier during non-development operation. The recovery unit is provided for at least the development unit other than the development unit that transfers the developing-agent image first in sequence among the plurality of development units. When one of the plurality of development units performs development by the developing agent whose charge capability is higher than that of the developing agent of the development unit that transfers the developing-agent image later in sequence, the recovery unit starts recovery of the developing agent or performs recovery operation for improving recovery capability of the developing agent.

Abstract: A replaceable unit is detachably attached into an image forming apparatus. The replaceable unit includes: a first cover member provided with a through hole that indicates a direction of the attachment and the detachment of the replaceable unit with respect to the image forming apparatus; and a second cover member having a color different from a color of the first cover member, and being formed to block the through hole from inner side of the replaceable unit when the first cover member is attached to the second cover member.

Abstract: Developing cartridges, each including a developing roller for carrying toner, are detachably mounted in a color laser printer. A drive current of a motor driving the developing rollers is detected as a load applied to a driving motion of the motor. If appropriate toner is being used, then the detected drive current is equal to or less than a predetermined value. However, if inappropriate toner is being used, then the detected drive current is greater than the predetermined value. In this case, printing is canceled so as to prevent formation of images with inappropriate toner and potential damage to the color laser printer.

Abstract: A latent image formed on a photosensitive member in exposure operations is developed into a toner image, which is then transferred onto an image bearing member in primary transfer operations. Afterward, the toner image is transferred onto a recording sheet in secondary transfer operations. A cleaning unit for cleaning the image bearing member by removing residual toner therefrom is brought into and out of contact with the surface of the image bearing member at a time when neither the exposure operations nor primary transfer operations are being performed.

Abstract: A tandem color laser printer 1 is provided with a photosensitive drum unit 15, a developing unit 14, and a scanning unit 13 for each color. The developing units 14, each including a main developer unit 25 and a toner hopper 24, and the scanning units 13, which irradiate laser beam, are alternately stacked vertically to overlap with each other in the vertical direction. This arrangement eliminates space required when arranging the developing units 14 and scanning units 13 side by side, thereby reducing the footprint of the color laser printer 1.

Abstract: A heat fixing device capable of preventing deterioration of a temperature sensor by measuring the surface temperature of a heating roller at all times, and an image forming apparatus. The heat fixing device includes a temperature measurement unit for measuring the surface temperature of the heating roller. The temperature measurement unit further includes the temperature sensor, a conduit having a reflective surface formed inside thereof to lead infrared rays radiating from the heating roller to the temperature sensor, and a thermal insulation member installed between the conduit and the temperature sensor.

Abstract: During a first rotation of a photoconductor, latent electrostatic images for color correction processing patterns are formed on the photoconductor, and the latent electrostatic images are developed into the color correction processing patterns in each of four colors, and then densities of the patterns on the photoconductor are detected. During a second rotation of the photoconductor, each color of the patterns is recovered back into a developer device.

Abstract: A tandem color laser printer 1 is provided with a photosensitive drum unit 15, a developing unit 14, and a scanning unit 13 for each color. The developing units 14, each including a main developer unit 25 and a toner hopper 24, and the scanning units 13, which irradiate laser beam, are alternately stacked vertically to overlap with each other in the vertical direction. This arrangement eliminates space required when arranging the developing units 14 and scanning units 13 side by side, thereby reducing the footprint of the color laser printer 1.

Abstract: An image forming device includes a housing, a photosensitive drum, a developing unit, and a developing-agent moving configuration. The developing unit is freely detachably attached to the housing and includes an exchangeable toner box and a developing chamber, which are freely detachably attached to each other. The toner box has a through hole for supplying toner to the developing chamber. The developing portion includes a developing roller that rotates to transport toner from the toner box to a latent image on the photosensitive drum. The developing-agent moving configuration functions to move residual toner from the developing chamber into the present toner box before the toner box is exchanged for a new toner box.

Abstract: A color blindness dialog box in a Properties window includes a color blindness process mode checkbox enabling a user to select a printing process designed for color blindness. When the color blindness process mode checkbox is checked, it is determined whether the image to be printed includes problematic areas for people with color blindness. If so, image data for these areas is extracted and displayed in a popup window. Subsequently, a borderline process is performed to form a borderline on either or both of the border areas and of text data and graphics data. Thus, the problematic areas are extracted and processed properly so that the problematic areas will become easy to distinguish.

Abstract: A system of printers uses replicable toner boxes, which each has a unique serial number. Each printer determines once the toner box is empty. At this time, the printer registers the serial number of the used toner box in used toner box list in a memory. Each time a toner box is mounted in the printer, the printer reads and compares the serial number of the freshly inserted toner box with the serial numbers in the list in the memory. If the serial number of the presently mounted toner box matches any in the list, this means that the toner box has previously been judged to reach life end, so the printer displays a message that the toner box is not suitable for use in the printer and prevents further printing operations until the toner box is replaced with a new one.

Abstract: Developing cartridges, each including a developing roller for carrying toner, are detachably mounted in a color laser printer. A drive current of a motor driving the developing rollers is detected as a load applied to a driving motion of the motor. If appropriate toner is being used, then the detected drive current is equal to or less than a predetermined value. However, if inappropriate toner is being used, then the detected drive current is greater than the predetermined value. In this case, printing is canceled so as to prevent formation of images with inappropriate toner and potential damage to the color laser printer.

Abstract: A thermal fixing device is for thermally fixing an image to a recording medium. The thermal fixing device includes an induction coil, a propagation member, and a thermal roller. The propagation member is made from a magnetic material that propagates magnetic flux induced by the induction coil. The thermal roller has a thermal region including an outer peripheral surface and an inner peripheral surface. One or both of the outer peripheral surface and the inner peripheral surface of the thermal region is formed from a magnetic material. The propagation member is magnetically connected to both axial lengthwise ends of magnetic-material ones of the outer peripheral surface and at the inner peripheral surface.