Abstract: A developing device includes two developer-transporting members, a container, and four gap retainers. The container contains a developer and rotatably supports rotation shafts of the developer-transporting members using side walls located on both end portions. The gap retainers are supported at end portions of the developer-transporting members and are brought into contact with a subjected-to-development member or a supporter to maintain a gap between the subjected-to-development member and each developer-transporting member. A force with which the two developer-transporting members are pressed toward the subjected-to-development member is applied to the container and all the gap retainers are brought into contact with the subjected-to-development member or the supporter, while axes of rotation of the two developer-transporting members are allowed to become non-parallel with an axis of rotation of the subjected-to-development member.

Abstract: A developing device includes developing units each including a first gear and a development roller; a rotation supporting member; a cam member having a cam surface surrounding the rotation axis, and being secured to and rotating together with the rotation supporting member; and a driving force transmission member including a cam receiving roller and a second gear. The cam surface includes a curved surface whose curvature is less than a curvature of the cam receiving roller so that, as the first gear approaches a driving position where the first gear receives the driving force from the second gear by the rotation of the cam member, the cam receiving roller is moved away from the rotation axis once, after which the cam receiving roller is moved towards the rotation axis, thereby starting engagement of the first gear with the second gear before the first gear reaches the driving position.

Abstract: A developing device includes: a casing that has a housing part, an upstream edge and a downstream edge, and a rectangular opening that opposes a development region, the rectangular opening being provided between the upstream and downstream edges; a cylindrical developer conveying body to rotate in a state of passing the rectangular opening, the cylindrical developer conveying body conveying the developer to the development region; and a flexible sheet member that has an upstream end part and a downstream end part, the upstream end part being fixed at the downstream edge of the casing, the downstream end part being a free end and coming into contact with a layer of the developer in a rotation axis direction of the developer conveying body at a position of the developer conveying body which passes the downstream edge of the opening.

Abstract: The invention provides a developer container that comprises a container main unit having a partition arranged at a position dividing a first transport space and a second transport space that are spaces in which developer is transported respectively, and an opening, and a lid that blocks the opening, and contacts the partition in a state in which the partition is bent when the opening is blocked, and the lid dividing the first transport space and the second transport space using a portion of the lid, which contacts the partition.

Abstract: A developing device includes developing units each including a first gear and a development roller; a rotation supporting member; a cam member having a cam surface surrounding the rotation axis, and being secured to and rotating together with the rotation supporting member; and a driving force transmission member including a cam receiving roller and a second gear. The cam surface includes a curved surface whose curvature is less than a curvature of the cam receiving roller so that, as the first gear approaches a driving position where the first gear receives the driving force from the second gear by the rotation of the cam member, the cam receiving roller is moved away from the rotation axis once, after which the cam receiving roller is moved towards the rotation axis, thereby starting engagement of the first gear with the second gear before the first gear reaches the driving position.

Abstract: A developing device includes a developer transport body that transports developer to develop an electrostatic latent image on an image carrier, a housing that holds the developer transport body and defines an exposed portion and an unexposed portion, the housing including a storage portion storing the developer, and a layer-thickness regulation member that regulates a layer thickness of the developer transported to the exposed portion and includes one side close to a surface of the developer transport body, a first portion, and a second portion. The housing includes first faces that define both ends of the storage portion in the rotation axis direction of the developer transport body, a second face, and a third face. The developing device further includes a closing member that closes a gap between the layer-thickness regulation member and the second and third faces, and a magnet provided between the second and third faces.

Abstract: The image forming apparatus is provided with: an image carrier; an exposure member that exposes the image carrier and forms an electrostatic latent image on the image carrier; a developing member that develops the electrostatic latent image formed on the image carrier; and a contact-retracting unit that rotates the developing member taking a predetermined position as the rotational center, and brings the developing member in contact with or proximity to the image carrier or retracts the developing member from the image carrier.

Abstract: There is provided a development apparatus including: a first developer storage container and a second developer storage container that store developer, having a first a and second openings, respectively; a first transport member provided within the first developer storage container, and that causes the developer to move to the second developer storage container via the first opening; a second transport member provided within the second developer storage container, and that causes the developer to move to the first developer storage container via the second opening; a developer holding member that performs development by causing the developer to move to a position facing an image holding body on which a latent image is formed; and a moving member provided so as to fit between an inner wall face of the second developer storage container and an outer edge of the second transport member.

Abstract: A developing device includes: a developing roll; a bearing member that supports the developing roll rotatably, the bearing member including plural outer side surfaces, and distances from a center of a rotation axis of the developing roll to the outer side surfaces being different; and a supporting member that supports the bearing member in a positioning state where one of the plural outer side surfaces is in contact with a reference surface, the outer side surface in contact with the reference surface being changeable.

Abstract: The invention provides a developer container that comprises a container main unit having a partition arranged at a position dividing a first transport space and a second transport space that are spaces in which developer is transported respectively, and an opening, and a lid that blocks the opening, and contacts the partition in a state in which the partition is bent when the opening is blocked, and the lid dividing the first transport space and the second transport space using a portion of the lid, which contacts the partition.

Abstract: A developing device includes: a casing that has a housing part, an upstream edge and a downstream edge, and a rectangular opening that opposes a development region, the rectangular opening being provided between the upstream and downstream edges; a cylindrical developer conveying body to rotate in a state of passing the rectangular opening, the cylindrical developer conveying body conveying the developer to the development region; and a flexible sheet member that has an upstream end part and a downstream end part, the upstream end part being fixed at the downstream edge of the casing, the downstream end part being a free end and coming into contact with a layer of the developer in a rotation axis direction of the developer conveying body at a position of the developer conveying body which passes the downstream edge of the opening.

Abstract: There is provided a development apparatus including: a first developer storage container and a second developer storage container that store developer, having a first a and second openings, respectively; a first transport member provided within the first developer storage container, and that causes the developer to move to the second developer storage container via the first opening; a second transport member provided within the second developer storage container, and that causes the developer to move to the first developer storage container via the second opening; a developer holding member that performs development by causing the developer to move to a position facing an image holding body on which a latent image is formed; and a moving member provided so as to fit between an inner wall face of the second developer storage container and an outer edge of the second transport member.

Abstract: The image forming apparatus is provided with: an image carrier; an exposure member that exposes the image carrier and forms an electrostatic latent image on the image carrier; a developing member that develops the electrostatic latent image formed on the image carrier; and a contact-retracting unit that rotates the developing member taking a predetermined position as the rotational center, and brings the developing member in contact with or proximity to the image carrier or retracts the developing member from the image carrier.