摘要:
A developing device (4) includes an accommodating casing (41), a rotatable developer carrying member (44), a regulating portion (42), a magnetic flux generating portion (44a) including a first magnetic pole (S3) and a second magnetic pole (S1) which have the same polarity, and a cover portion (48) provided downstream of the developing region and upstream of a maximum magnetic flux density position of the second magnetic pole with respect to a rotational direction of the developer carrying member. The cover portion is disposed between the casing and the developer carrying member. A downstream end of the cover portion with respect to the rotational direction is in a side upstream, with respect to the rotational direction, of a minimum magnetic flux density position between the first magnetic pole and the second magnetic pole with respect to the rotational direction.
摘要:
Provided is a transfer belt (1) which is capable of implementing a high transfer property even for a recording medium (1000) having concave-convex portions on the surface and suppressing degradation in an image grade by repetitive use. The transfer belt (1) transfers a toner image carried on a first main surface (1a, 21s1') onto a recording medium (1000) and includes at least an elastic layer (3). When the transfer belt (1) is pressed by pressing force at a predetermined pressing speed and then pressed by constant pressing force using a lower block (110) including a curved convex surface (112) having a hole section (113) formed therein and an upper block (120) including a curved concave surface (122), if a maximum value of displacement in a measurement region (MR) which is a portion corresponding to the hole section (113) in the first main surface (1a, 21s1') is indicated by "a" [µm], and displacement of the measurement region (MR) after the displacement of the measurement region (MR) converges is "b" [µm], E [-] calculated by (a - b)/b using "a" and "b" satisfies a condition of 0.2 ≤ E ≤ 3.
摘要:
A transfer assembly includes a counter member having a contact face, an engagement/disengagement unit to engage and disengage the image carrying face of image carrying member and the contact face of counter member using a cam, a pressure device to apply force to a transfer nip between the image carrying face and contact face, and a recording medium feed device to feed the recording medium to the transfer nip. When the cam is at a first rotation position, the image carrying face and contact face are separated, and when the cam is at a second rotation position, the image carrying face and contact face contact. Before the recording medium enters the transfer nip, the cam rotates from the first rotation position toward the second rotation position. After the recording medium enters the transfer nip, the cam is at the second rotation position to press the image carrying face with the contact face.
摘要:
A roller mechanism includes a pair of rollers and an urging unit. The pair of rollers oppose one another sandwiching a conveyance path of a sheet material, and are provided to be capable of increasing and reducing an axis-to-axis separation thereof. The urging unit urges at least one of the pair of rollers in a direction of reducing the axis-to-axis separation of the pair of rollers with an urging force that increases with an increase in the axis-to-axis separation of the pair of rollers, and presses the sheet material with the pair of rollers. The urging unit increases the urging force non-linearly, with a rate of increase of the urging force falling as the axis-to-axis separation of the pair of rollers increases within a range of changes at times of sheet material-pressing.
摘要:
An image forming apparatus (1, 1, 1") includes multiple image forming units (20Y, 20C, 20M) disposed adjacent to and horizontally aligned with each other, a first transfer member (15) to sequentially transfer and overlay respective single non-black color images thereon, a black image forming unit (20K, 20K', 20K") disposed separately from the multiple image forming units (20Y, 20C, 20M) including a black image carrier (2K) and a black image developing unit (4K, 4K'), a second transfer member (12) to transfer the black image from the black image forming unit (20K, 20K', 20K") onto a recording medium, a first cleaning unit (5K) to clean the black image carrier (2K), and a second cleaning unit (13) to clean the second transfer member (12). The black toner removed from the surface of the black image carrier (2K) is collected to the black image developing unit (4K, 4K').
摘要:
An electrophotographic image forming apparatus for enhancing color registration is provided. The electrophotographic image forming apparatus includes a developing unit (110Y,110M,110C,110K) including a photosensitive medium (114Y,114M,114C,114K), an image transferring device (140), and a paper feeding device. The image transferring device includes a pair of conveying rollers (143,145), a conveying belt (141), and a plurality of transfer rollers (150Y,150M,150C,150K). The conveying belt is supported by the conveying rollers and rotates around the conveying rollers and conveys a recording medium by attaching a recording medium to a surface thereof. The plurality of transfer rollers are disposed inside the conveying belt and form a transfer nip between the recording medium and the photosensitive medium. The paper feeding device provides the recording medium to the image transferring device. The force of the image transferring device that maintains the position of the recording medium with respect to the conveying belt (141) during image transferring is equal to or greater than the maximum force applied to the recording medium by the paper feeding device (126,129).
摘要:
A belt (56) is looped around a plurality of rollers including a drive roller (52) and a follow roller (54). The belt has an inner peripheral surface facing inside of a loop of the belt and an outer peripheral surface opposite the inner peripheral surface. The belt has a first widthwise edge (56c) and a second widthwise edge (56d). A widthwise-movement restricting member (81) is disposed on the inner peripheral surface on a first widthwise edge side. The widthwise-movement restricting member restricts widthwise movement of the belt in a direction toward a second widthwise edge side. An expansion-contraction restricting member (82) is disposed on the second widthwise edge side on at least one of the inner peripheral surface and the outer peripheral surface. The expansion-contraction restricting member is less expandable in a peripheral direction of the belt than the widthwise-movement restricting member is. An urging member (85) applies tension to the belt in the peripheral direction.
摘要:
An image forming apparatus (100) which includes an image carrier (1) configured to form a toner image, a transfer roller (5) configured to transfer the toner image to a recording medium, a gap controlling member (7) configured to keep a predetermined distance between the image carrier (1) and the transfer roller (5) and a cleaning member (16) configured to clean a surface of the image carrier, arranged to touch a contacting area on the surface of the image carrier (1) with the gap controlling member (7) and formed of a porous fibrous material in at least a contacting area of the cleaning member (16) contacting with the image carrier (1).