Abstract: A developing unit and a developer stirring and transporting method are provided that enable smooth discharge of a developer in the developing unit without being affected by the inclination of the developing unit. A developing unit 10 has a developing roller 12, a housing unit 16 configured to house a developer and having in its sidewall a discharge port 14 which discharges overflowing developer, a stirring and transporting member 20 configured to stir and transport the developer along a passage 18 formed in the housing unit 16, and a deposit structure unit 22 provided in the passage 18 and configured to raise the height position of a bottom surface 18a part of the passage 18 corresponding at least to the discharge port 14 to a position higher than the other areas of the passage 18, and thereby deposit the developer near the discharge port 14.

Abstract: A developer vent is provided on the wall of the developer container housing developer including toner and carrier for the developing device to overflow developer. The sectional shape of the discharge dam forming the developer vent in the vertical direction to the developer vent is such that the top part of the dam is made thinner than the wall thickness of the developer container and the slanting angle of the dam to the wall of the developer container is made larger than the repose angle of the developer.

Abstract: An image forming apparatus that forms an image using a photoconductor body includes a switching unit which effects switching between a state in which a cleaner is operated for the photoconductor body, and a state in which the cleaner is not operated for the photoconductor body. A control unit is provided which controls a setting change of an image formation condition between a case where the cleaner is operated by the switching unit, and a case where the cleaner is not operated by the switching unit. The switching unit includes a detection unit which detects the kind of paper on which an image is formed, and the switching unit switches on/off the cleaner in accordance with a detection result of the detection unit.

Abstract: There are provided a developing unit and a developer stirring and transporting method in which the amount of developer in the developing unit can always be kept at a specified amount without being influenced by a use environment. A developing unit 10 includes a developing roller 12, a containing unit 16 to contain the developer and having a discharge port 14 to discharge the overflown developer in its side wall, a stirring and transporting member 20 to stir and transport the developer along a passage 18 formed in the containing unit 16, and a guide unit 22 provided in the passage 18 correspondingly to the discharge port 14 of the containing unit 16 and to guide the developer transported in the passage 18 by the stirring and transporting member 20 to the discharge port 14 side.

Abstract: There are provided a developing apparatus and a developer collecting method, in which a collection unit to collect a developer discharged from a developing unit by overflow is disposed not to largely protrude to the outside of an installation space of the developing unit. There are included a developing unit 12 including a discharge port 30 to discharge a developer by overflow, and a developer collecting unit 34 that is disposed so that at least a part overlaps with the developing unit 12 when the developing unit 12 is viewed from above, and contains the developer discharged from the discharge port 30 of the developing unit 12.

Abstract: A cleanerless cartridge in which a photoconductor body and a charger are integrated, and a cleaner-equipped cartridge in which a photoconductor body, a charger and a cleaner are integrated are prepared. An image forming apparatus body is configured such that the cartridges are attachable to first- to fourth-stage image forming sections. When the cleanerless cartridge is attached to the first- to fourth-stage image forming sections, an image forming operation is controlled under an image formation condition for a cleanerless process. When the cleaner-equipped cartridge is attached to the first- to fourth-stage image forming sections, an image forming operation is controlled under an image formation condition for a cleaner-equipped process.

Abstract: In a color image forming apparatus of the invention, a developing roller of a developing device includes a magnet roller that is configured such that a developer supply pole, a developer convey pole and a developer release pole are properly arranged and fixed. The developer roller also includes an outer cylindrical roller that is formed of an electrically conductive material such as aluminum. A surface of the cylindrical roller is processed to have irregularities. Using the developing roller, simultaneous development/cleaning is executed. Thus, 100% of toner contributes to image formation, and no waste toner is produced. Post-transfer residual toner on a photoconductor body is efficiently recovered to the developing roller, and occurrence of an image defect such as development memory can be prevented.

Abstract: A cleanerless cartridge in which a photoconductor body and a charger are integrated, and a cleaner-equipped cartridge in which a photoconductor body, a charger and a cleaner are integrated are prepared. An image forming apparatus body is configured such that the cartridges are attachable to first- to fourth-stage image forming sections. When the cleanerless cartridge is attached to the first- to fourth-stage image forming sections, an image forming operation is controlled under an image formation condition for a cleanerless process. When the cleaner-equipped cartridge is attached to the first- to fourth-stage image forming sections, an image forming operation is controlled under an image formation condition for a cleaner-equipped process.

Abstract: A CPU controls a shutter of a developing device so as to enable movement of a developer between a first chamber and a second chamber that store the developer. The CPU rotates a developing roller and mixers of the first and second chambers for a predetermined time T, and stirs and conveys the developer. Thereby, the developer is moved from the first chamber into the second chamber. The amount of movement of the developer is understandable from the rotational speed and shape of each mixer. Hence, the amount of developer, which is moved from the first chamber to the second chamber, is estimated in advance, and about half the developer in the first chamber is replaced.

Abstract: There is provided an image forming apparatus comprising a developing device containing a toner having an average particle diameter of 2 to 5 ?m and a spherical degree of 1 to 1.2, and a transfer member which is pressed against the image carrier by a pressing force having a total load of 150 g to 1500 g and a surface load of 10 to 150 g/cm2 at the time of transfer.

Abstract: A developer bent is provided on the wall of the developer container housing developer comprising toner and carrier for the developing device to overflow developer. The sectional shape of the discharge dam forming the developer bent in the vertical direction to the developer bent is such that the top part of the dam is made thinner than the wall thickness of the developer container and the slanting angle of the dam to the wall of the developer container is made larger than the repose angle of the developer.

Abstract: In a color image forming apparatus of the invention, a developing roller of a developing device includes a magnet roller that is configured such that a developer supply pole, a developer convey pole and a developer release pole are properly arranged and fixed. The developer roller also includes an outer cylindrical roller that is formed of an electrically conductive material such as aluminum. A surface of the cylindrical roller is processed to have irregularities. Using the developing roller, simultaneous development/cleaning is executed. Thus, 100% of toner contributes to image formation, and no waste toner is produced. Post-transfer residual toner on a photoconductor body is efficiently recovered to the developing roller, and occurrence of an image defect such as development memory can be prevented.

Abstract: A CPU controls a shutter of a developing device so as to enable movement of a developer between a first chamber and a second chamber that store the developer. The CPU rotates a developing roller and mixers of the first and second chambers for a predetermined time T, and stirs and conveys the developer. Thereby, the developer is moved from the first chamber into the second chamber. The amount of movement of the developer is understandable from the rotational speed and shape of each mixer. Hence, the amount of developer, which is moved from the first chamber to the second chamber, is estimated in advance, and about half the developer in the first chamber is replaced.

Abstract: A cleanerless cartridge in which a photoconductor body and a charger are integrated, and a cleaner-equipped cartridge in which a photoconductor body, a charger and a cleaner are integrated are prepared. An image forming apparatus body is configured such that the cartridges are attachable to first- to fourth-stage image forming sections. When the cleanerless cartridge is attached to the first- to fourth-stage image forming sections, an image forming operation is controlled under an image formation condition for a cleanerless process. When the cleaner-equipped cartridge is attached to the first- to fourth-stage image forming sections, an image forming operation is controlled under an image formation condition for a cleaner-equipped process.

Abstract: An image forming apparatus includes a charging device that, by allowing a brush roller to be rotated so as to be set in contact with a surface of a photosensitive body, charge the surface of an image carrier, a light exposure device that radiates image information light onto the surface of the image carrier to form an electrostatic latent image, a developing device that develops the electrostatic latent image into a developing agent image, a transfer device that transfers the developing agent to a sheet, and a guide device that guides an outer periphery of the brush roller so as to prevent the image information light from being blocked by the brush roller.

Abstract: An image forming apparatus comprises a charging device configured to, by allowing a brush roller to be rotated in such a state as to be set in contact with a surface of a photosensitive body, charge the surface of that image carrier, a light exposure device configured to radiate image information light onto the surface of the image carrier charged by the charging device to form an electrostatic latent image, a developing device configured to develop the electrostatic latent image formed by the light exposure device into a developing agent image, a transfer device configured to transfer the developing agent image which is developed by the developing device to a sheet, and a guide device configured to guide an outer periphery of the brush roller so as to prevent the image information light which is radiated toward the photosensitive body from being blocked by the brush roller of the charging device.

Abstract: After a printer section is used to form an image on one surface of a sheet, the sheet is once discharged into a sheet discharge tray disposed outside an apparatus main body. Thereafter, the sheet is supplied into the apparatus main body, and the printer section is used to form an image on the other surface of the sheet. The sheet having the opposite surfaces printed in this manner is discharged to an upper portion of the sheet discharge tray. It is unnecessary to dispose a conventional stack cassette for reversing the sheet and a sheet conveyance path having sharp corners inside the apparatus main body.

Abstract: A developing roller according to the invention has an outer circumferential surface, which can be set in frictional contact with a photosensitive belt that is stretched to be driven in a prescribed direction. The outer surface is divided into two mirror surfaces and a rough surface. The mirror surfaces are provided on the end portions of the roller, they do not retain developer. The rough surface extends between the mirror surfaces, for retaining developer. Spacer means prevents the photosensitive belt from coming into frictional contact with the mirror surfaces. The mirror surfaces are therefore prevented from scraping the photosensitive belt. This prolongs the lifetime of the photosensitive belt.

Abstract: An image forming apparatus which includes a platen for transporting a recording medium at a prescribed speed, a ribbon drive for transporting a thermoplastic ink ribbon which has a thermoplastic agent and thermal expansible particles contained in the thermoplastic agent in parallel with the recording medium at a speed slower than the transporting speed of the recording medium and a heater for selectively heating the thermoplastic ink ribbon so as to transfer the thermoplastic agent onto the recording medium.

Abstract: An image formation cartridge employed to a printer includes a movable image formation sheet supported between a pair of rotatable shafts, a rotatable ink applying roller unit contacting the image formation sheet and an ink feeding unit for feeding ink from an ink storing container to the ink applying roller unit. The image formation sheet may be wound on one of the pair of rotatable shafts as the shafts rotate in the same direction. Ink may continuously be applied to the image formation sheet through the ink feeding unit and the ink applying roller unit as the shafts rotate.