Abstract: This electrophotographic photosensitive body (20) comprises a supporting body (20a) and a photosensitive layer (20b) that is formed on the surface of the supporting body (20a). The surface of the photosensitive layer (20b) has an arithmetic mean roughness Ra within the range of from 20 nm to 100 nm (inclusive), a ten-point average roughness Rz within the range of from 0.2 ?m to 1.0 ?m (inclusive) and a mean spacing of profile irregularities Sm of 20 ?m or less in the initial stage of use.

Abstract: This electrophotographic photosensitive body (20) comprises a supporting body (20a) and a photosensitive layer (20b) that is formed on the surface of the supporting body (20a). The surface of the photosensitive layer (20b) has an arithmetic mean roughness Ra within the range of from 20 nm to 100 nm (inclusive), a ten-point average roughness Rz within the range of from 0.2 ?m to 1.0 ?m (inclusive) and a mean spacing of profile irregularities Sm of 20 ?m or less in the initial stage of use.

Abstract: An image forming apparatus includes an image carrying member, a driving device, a charging member, a cleaning member, a voltage applying device, a torque detector for detecting the torque of the driving device, a storage for storing a predetermined torque value Tc, and a control portion. The control portion obtains as Ton the torque when the charging voltage is applied to the charging member and obtains as Toff the torque when no charging voltage is applied to the charging member. Let the torque observed when no charging voltage is applied at an early stage of use of the image carrying member be represented by Toff(0), then, when the relations Toff(0)<Toff and Tc<Ton/Toff hold, the control portion determines that the degree of smoothness of the surface of the image carrying member is equal to or higher than a predetermined degree of smoothness.

Abstract: An image forming device includes an image carrier on the surface of which a toner image is formed, a cleaning member arranged in contact with, for cleaning, the surface of the image carrier, a charging member for electrostatically charging the image carrier, a bias applying device, and a control portion. The bias applying device applies a charging bias having DC and AC biases superimposed on each other to the charging member. The control portion controls the charging bias applied to the charging member by the bias applying device. As the AC bias applied to the charging member, the control portion uses, in a first period from the start of use of the image carrier to a predetermined time thereafter, a first AC bias and, in a second period subsequent to the first period, a second AC bias higher than the first AC bias.

Abstract: An image forming apparatus includes an image carrying member, a driving device, a charging member, a cleaning member, a voltage applying device, a torque detector for detecting the torque of the driving device, a storage for storing a predetermined torque value Tc, and a control portion. The control portion obtains as Ton the torque when the charging voltage is applied to the charging member and obtains as Toff the torque when no charging voltage is applied to the charging member. Let the torque observed when no charging voltage is applied at an early stage of use of the image carrying member be represented by Toff(0), then, when the relations Toff(0)<Toff and Tc<Ton/Toff hold, the control portion determines that the degree of smoothness of the surface of the image carrying member is equal to or higher than a predetermined degree of smoothness.

Abstract: An image forming device includes an image carrier on the surface of which a toner image is formed, a cleaning member arranged in contact with, for cleaning, the surface of the image carrier, a charging member for electrostatically charging the image carrier, a bias applying device, and a control portion. The bias applying device applies a charging bias having DC and AC biases superimposed on each other to the charging member. The control portion controls the charging bias applied to the charging member by the bias applying device. As the AC bias applied to the charging member, the control portion uses, in a first period from the start of use of the image carrier to a predetermined time thereafter, a first AC bias and, in a second period subsequent to the first period, a second AC bias higher than the first AC bias.

Abstract: An image forming apparatus is provided with an image forming portion, a collecting duct, a toner collecting device, a toner collecting device, and a first control portion. Into the collecting duct, unnecessary toner generated in the image forming portion flows together with an airflow. The toner collecting device communicates with the collecting duct, has a path of the airflow formed therein, and collects, by using a filter, the toner together with the airflow generated by an airflow generating portion. The first control portion controls an operation condition of a vibrating operation of a vibrating portion that vibrates the filter, in accordance with at least one of setting conditions relating to environment of the image forming portion, a coverage rate of a toner image, the number of printed sheets, and an image density of the toner image.

Abstract: An image forming apparatus is provided with an image forming portion, a collecting duct, a toner collecting device, a toner collecting device, and a first control portion. Into the collecting duct, unnecessary toner generated in the image forming portion flows together with an airflow. The toner collecting device communicates with the collecting duct, has a path of the airflow formed therein, and collects, by using a filter, the toner together with the airflow generated by an airflow generating portion. The first control portion controls an operation condition of a vibrating operation of a vibrating portion that vibrates the filter, in accordance with at least one of setting conditions relating to environment of the image forming portion, a coverage rate of a toner image, the number of printed sheets, and an image density of the toner image.

Abstract: Provided is a toner dispersing mechanism arranged between a toner storage container and a developing device, for dispersing toner replenished from the toner storage container. The toner dispersing mechanism includes a housing, a toner dispersing member, and a projecting portion formed continuously at least at a part of an inner wall surface in a longitudinal direction of the housing. The housing includes a toner filling port communicating to the toner storage container, and a toner discharge port communicating to the developing device. The toner dispersing member includes a rotary shaft rotatably supported in the housing, and a large number of dispersing protrusions made of an elastic material and formed on an outer peripheral surface of the rotary shaft. The large number of dispersing protrusions face the part and come into contact with the projecting portion.

Abstract: A developer includes a developer carrying body that carries a two-component developer having a magnetic toner and a carrier. A toner carrying body opposes the developer carrying body and receives toner from the developer carrying body. An image carrying body develops an electrostatic latent image by toner carried on the toner carrying body. A first magnetic member is inside the developer carrying body and opposes a surface of the toner carrying body. A second magnetic member is inside the toner carrying body and opposes the surface of the developer carrying body. The second magnetic member is magnetized to an opposite polarity to the first magnetic member and generates a magnetic force at least on the surface of the toner carrying body in a range of 25 mT to 40 mT in a direction perpendicular to the surface of the toner carrying body.

Abstract: Provided is a toner dispersing mechanism arranged between a toner storage container and a developing device, for dispersing toner replenished from the toner storage container. The toner dispersing mechanism includes a housing, a toner dispersing member, and a projecting portion formed continuously at least at a part of an inner wall surface in a longitudinal direction of the housing. The housing includes a toner filling port communicating to the toner storage container, and a toner discharge port communicating to the developing device. The toner dispersing member includes a rotary shaft rotatably supported in the housing, and a large number of dispersing protrusions made of an elastic material and formed on an outer peripheral surface of the rotary shaft. The large number of dispersing protrusions face the part and come into contact with the projecting portion.

Abstract: A developing device includes a container storing a two-component developer including a toner and a carrier, a toner carrying body carrying the toner in the container and supplying the toner to a predetermined image carrying body by rotation, a restricting member held in press contact with the toner carrying body, and a restricting nip section formed between the toner carrying body and the restricting member. The restricting nip section selects only the toner in the two-component developer to form a uniform toner layer on the toner carrying body.

Abstract: An image forming apparatus is provided with a photoconductor to have an electrostatic latent image formed thereon, a developing device for developing the electrostatic latent image with a toner, a toner replenishing device for replenishing the toner into the developing device, and a controller for controlling an image developing operation by the developing device and a toner replenishing operation by the toner replenishing device. The controller executes a non-replenishment mode for causing the developing device to perform image development without being replenished with the toner from the toner replenishing device, a discharge mode, following the non-replenishment mode, for discharging the toner remaining in the developing device and a refill mode, following the discharge mode, for refilling the toner into the developing device by the toner replenishing device.

Abstract: A developing device supplies developer to an electrostatic latent image bearing body of an image forming apparatus. The developing device includes a container housing with an opening in a position opposite to the electrostatic latent image bearing body and stores developer to be supplied to the electrostatic latent image bearing body. A developing roller is rotatably disposed so that a part of the developing roller is exposed from the opening. A regulator is disposed along an axial direction of the developing roller and has a leading end facing the developing roller to regulate the thickness of developer layer on the developing roller. Two holders support the developing roller and the regulator on the container housing. Each holder includes a developing roller support for supporting an end part of the developing roller and a regulator retainer for retaining the regulator on the container housing.

Abstract: A developing device includes a container storing a two-component developer including a toner and a carrier, a toner carrying body carrying the toner in the container and supplying the toner to a predetermined image carrying body by rotation, a restricting member held in press contact with the toner carrying body, and a restricting nip section formed between the toner carrying body and the restricting member. The restricting nip section selects only the toner in the two-component developer to form a uniform toner layer on the toner carrying body.

Abstract: A developer includes a developer carrying body that carries a two-component developer having a magnetic toner and a carrier. A toner carrying body opposes the developer carrying body and receives toner from the developer carrying body. An image carrying body develops an electrostatic latent image by toner carried on the toner carrying body. A first magnetic member is inside the developer carrying body and opposes a surface of the toner carrying body. A second magnetic member is inside the toner carrying body and opposes the surface of the developer carrying body. The second magnetic member is magnetized to an opposite polarity to the first magnetic member and generates a magnetic force at least on the surface of the toner carrying body in a range of 25 mT to 40 mT in a direction perpendicular to the surface of the toner carrying body.

Abstract: A low cost image forming apparatus can be provided in which the amount of remaining toner of each color in each development apparatus can be detected by a single detection sensor device and at the same time whether the development apparatus is attached to or detached from the image forming apparatus can be discerned by the detection sensor device. The image forming apparatus includes development apparatuses for each color for developing an electrostatic latent image and supply of the developer is controlled based on the detected amount of toner in each of the development apparatuses. The detection sensor device includes a light emitting member and a light receiving member which receives the light emitted from the light emitting member and output a detection signal in accordance with the intensity of received light.

Abstract: An image forming apparatus is provided with a photoconductor to have an electrostatic latent image formed thereon, a developing device for developing the electrostatic latent image with a toner, a toner replenishing device for replenishing the toner into the developing device, and a controller for controlling an image developing operation by the developing device and a toner replenishing operation by the toner replenishing device. The controller executes a non-replenishment mode for causing the developing device to perform image development without being replenished with the toner from the toner replenishing device, a discharge mode, following the non-replenishment mode, for discharging the toner remaining in the developing device and a refill mode, following the discharge mode, for refilling the toner into the developing device by the toner replenishing device.

Abstract: In an image forming apparatus that uses toners of a plurality of different colors, amorphous toner is used during image forming with a first color. Then, a controller, by using a toner remaining-removing switching device, causes toner scraped off from an image carrier by a blade during cleaning to remain at a predetermined region near the blade. Spherical toner is used during image forming with a second color and thereafter. The controller switches the toner remaining-removing switching device during any one of processes starting from the process of the second color until the end of image formation to remove toner remaining at the predetermined region, and the toner subsequently scraped off, from the image carrier.

Abstract: In image formation of a black-line image, the image is developed with black toner, and in addition parts of the black-line image corresponding to an intersection between at least two black lines and a middle portion of a black line are developed with toner of at least one of cyan, yellow, and magenta colors overlaid. This makes it possible to prevent central voids in a black-line image. In a black-line image transferred onto a transfer medium by this full-color image forming apparatus, not only are central voids eliminated, but degradation of image quality is also prevented.