摘要:
The present invention relates to a developing device for developing images formed on an image carrier. The device is capable of regulating toner amount such that the amount of toner conveyed by the toner control to the developing area is reduced, as well a appropriately changing the carrier.
摘要:
A low-heat loss, belt nip-type fixing device achieves good recording medium separation performance without increasing the size of the device, prevents image misalignment, and achieves a high-quality image without placing a major burden on the recording medium. This fixing device comprises a heat-fixing roller having an elastic layer and a heat source; and a pressurizing unit having an elastic member with a flat surface for pressing an endless member. The endless member conveys a recording medium, against the elastic layer. A pressurizing spring biases the elastic member toward the side of the recording medium. Biasing is carried out using the pressurizing spring such that the amount of deformation of the elastic member approaches the saturation region (maximum amount of deformation) inside a region of a nip portion, which is formed between the elastic layer of the heat-fixing roller and the endless member of pressurizing unit, and through which is passed a recording medium carrying an unfixed toner image.
摘要:
A fusing apparatus for fusing a toner image onto a recording medium using heat and pressure includes a fusing roller; an endless pressing belt disposed opposite the fusing roller; and a pressing member for pressing the endless pressing belt onto the fusing roller. A recording medium with a transferred toner image is passed through a fusing nip between the fusing roller and the pressing belt. The fusing roller includes positive and negative crown portions along the axial direction. The pressing member includes convex and concave surface portions along the longitudinal direction. When the pressing member is pressed onto the fusing roller, the positive and negative crown portions of the fusing roller are engaged with the concave and convex surface portions, respectively, of the pressing member. The pressing member exerts a greater pressing force on the fusing roller at a central portion than at an end portion.
摘要:
A fixing device includes a fixing member of which surface is deformable, a heating unit that heats the fixing member, a pressurizing unit having an endless member and a pressurizing member. The pressurizing member includes an elastic layer and presses the endless member against the fixing member to bring the endless member into pressure contact with the fixing member. The elastic layer has an apparent hardness (ASKER-C) which is larger than that at a point where an apparent hardness starts to change rapidly with respect to a rubber thickness in a load application direction.
摘要:
A pressurizing unit includes an elastic member that has an entering portion on a side from where a recording medium enters a nip portion, an exit portion on a side from where the recording medium exits the nip portion, and a center portion between the entering portion and the exit portion. The elastic modulus of the center portion is higher than elastic moduli of the entering portion and the exit portion.
摘要:
A belt device includes an endless belt and a rotary driver contacting an outer circumferential surface of the belt to drive and rotate the belt. An opposed belt support is disposed opposite the rotary driver and in contact with an inner circumferential surface of the belt. A rotary belt support is disposed opposite the rotary driver via the opposed belt support and in contact with the inner circumferential surface of the belt. A belt support holder holds the opposed belt support and the rotary belt support to retain a predetermined interval between the opposed belt support and the rotary belt support. A biasing assembly presses against the belt support holder to move the opposed belt support and the rotary belt support collectively with respect to the rotary driver and bias the opposed belt support against the rotary driver.
摘要:
An image forming apparatus includes an image forming device to form a cleaning toner image in a cleaning region on a cleaning sheet and a check toner image in a check region on the cleaning sheet. The image forming apparatus further includes a fixing device including a first rotator and a heater to heat the first rotator to a cleaning temperature that is lower than a fixing temperature to which the first rotator is heated in a print job and higher than a cold offset temperature at which toner adheres to the first rotator by cold offset. Each of the cleaning region and the check region has a length greater than a circumferential length of the first rotator. The cleaning region and the check region are disposed at a leading section and a trailing section of the cleaning sheet in a cleaning sheet conveyance direction, respectively.
摘要:
A fixing device includes a first member. The first member extends along a first longitudinal axis, and has an external surface whose thickness varies along the first longitudinal axis to define at least one first convex portion and at least one first concave portion. A thickness of the first convex portion is larger than a thickness of the first concave portion. A heating source is disposed in the first member. The heating temperature of an inner circumference side of the first convex portion is higher than the heating temperature of the inner circumference side of the first concave portion.
摘要:
A fixing device includes a first member and a second member. The first member extends along a first longitudinal axis, and has a first elastic layer whose thickness varies along the first longitudinal axis to define at least one first convex portion and at least one first concave portion. The second member extends along a second longitudinal axis parallel to the first longitudinal axis, and has a second elastic layer whose thickness varies along the second longitudinal axis to define at least one second convex portion and at least one second concave portion. At least one of the first and second members is heated, and at least one of the first and second members is pressed against the other, with the first convex portion engaging the second concave portion and the first concave portion engaging the second convex portion, to define a fixing nip therebetween.
摘要:
A fixing device to fix a toner image on a recording medium, including a pressure roller to press the toner image on the recording medium; an elastically-deformable cylindrical fixing roller to contact the pressure roller to form a nip and transfer the recording medium to the nip to fix the toner image; and a holder to rotatably hold both ends of the fixing roller, wherein the holder is located at least two positions at both sides on an outer circumference of the fixing roller across the longest diameter thereof, and the nip is formed between the two holders at the side of the pressure roller.