An example device to develop an electrostatic latent includes first and second passages coupled to each other through first and second openings. A first stir-and-transport member located in the first passage includes a first helical blade to stir and transport a developer along the first passage in a first direction and to supply the developer to a developing roller. A second stir-and-transport member located in the second passage includes a second helical blade to stir and transport the developer along the second passage in a second direction. A developer discharge pipe is coupled to the developer container to communicate with a downstream side of the first passage. The first stir-and-transport member includes a first reverse helical blade having a pitch between approximately 0.5 times and 1.5 times the pitch of the first helical blade and located downstream of the first helical blade and disposed downstream of the second opening.

A molding device for molding a magnet roll with a profiled cross-section comprises a heating and kneading unit that supplies, to a cylindrical metal mold, a kneaded material obtained by heating and kneading a raw mixture including ferromagnetic particles and thermoplastic resin, an extrusion molding unit that molds the supplied kneaded material by the metal mold, and a magnetic field generating unit disposed at an end portion of the metal mold in a lengthwise direction that generates a magnetic field inside the metal mold, and the metal mold has a profiled C-shaped cross-section at an inlet for the kneaded material and a profiled cross-section at an outlet for the kneaded material more complex than the inlet.

At an end, in a longitudinal direction, of an opening in a container containing a magnetic developer, an overlap portion is provided in which a developer bearing member, a regulating member, a sealing member, and the container are arranged so as to sequentially contact one another in a direction orthogonal to a rotation axis direction. A magnetic field generating member provided inside the developer bearing member has a first area where a value of a magnetic flux density is a predetermined value in the rotation axis direction and a second area including a local minimum portion in which the value is a minimum value, within a range from an end of the second area connected to the first area to an outer end of the overlap portion in the rotation axis direction.

An imaging system includes: a housing including a developing chamber, a developing roller located in the developing chamber to transport a developer and spaced apart from the housing; a conveyance path extending along at least part of a periphery of the developing roller in order to form a flow of air including the developer; and a control member. The developing roller includes a peeling pole at a fixed position with respect to the housing, to discharge the developer. The control member is located along the conveyance path in proximity to the peeling pole of the developing roller, to reduce a flow rate of the air flowing through the conveyance path.

An example developing device includes a housing to contain a developer and having an opening, a developing sleeve provided in the housing and partially exposed to the outside of the housing through the opening, a magnetic member including a plurality of magnetic poles and located inside the developing sleeve, and an elastic member blocking an inflow of air through a space between a downstream edge of the opening in a rotation direction of the developing sleeve and an outer circumferential surface of the developing sleeve. The elastic member includes a fixed portion fixed to the housing at a position adjacent to the downstream edge of the opening and an extension portion extending from the fixed portion in a bent form in the rotation direction of the developing sleeve to be elastically in contact with the surface of the developing sleeve.

A developing device includes: a housing in which a developer is contained; a cover member configured to cover an upper opening of the housing; a developer holder that is supported by the housing and holds the developer on an outer surface and rotates; a regulating member that faces the developer holder and configured to regulate an amount of the developer on the outer surface; a first exit path inclined toward an inside of the housing and configured to exit air from the inside of the housing to an outside of the cover member; and a second exit path that connects the first exit path and a filter member provided on the cover member, the filter member preventing passage of the developer and allowing passage of the air.

An example developing device includes a housing to contain a developer and having an opening, a developing sleeve provided in the housing and partially exposed to the outside of the housing through the opening, a magnetic member including a plurality of magnetic poles and located inside the developing sleeve, and an elastic member blocking an inflow of air through a space between a downstream edge of the opening in a rotation direction of the developing sleeve and an outer circumferential surface of the developing sleeve. The elastic member includes a fixed portion fixed to the housing at a position adjacent to the downstream edge of the opening and an extension portion extending from the fixed portion in a bent form in the rotation direction of the developing sleeve to be elastically in contact with the surface of the developing sleeve.

According to an aspect of the invention, a developing device includes a developer holding member that holds developer including toner which is charged to have a predetermined polarity on a surface and performs development of an electrostatic latent image with respect to an image holding member which holds the electrostatic latent image while being rotated; a storage member that stores the developer therein and has an opening portion for discharging air in which flow is generated by the rotation of the developer holding member; and a collection member that is provided in the opening portion of the storage member to be charged to the predetermined polarity, causes air to pass therethrough, and collects toner.

An imaging system includes: a housing including a developing chamber, a developing roller located in the developing chamber to transport a developer and spaced apart from the housing; a conveyance path extending along at least part of a periphery of the developing roller in order to form a flow of air including the developer; and a control member. The developing roller includes a peeling pole at a fixed position with respect to the housing, to discharge the developer. The control member is located along the conveyance path in proximity to the peeling pole of the developing roller, to reduce a flow rate of the air flowing through the conveyance path.

A developing apparatus includes a developer container that stores developer, a conveyance screw including a shaft portion and a blade, a bearing portion configured to engage with an engagement portion of the shaft portion of the conveyance screw, and a magnetic seal member having a magnetic property and disposed along a peripheral surface of the shaft portion in a noncontact manner with respect to the shaft portion between the blade and the engagement portion in the rotational axis direction of the conveyance screw.