A developing device includes: a storage part in which a developer is stored; a transport body that includes a spiral blade and transports the developer via a rotation thereof; a developing body to which the developer is supplied from the transport body; an attachment part which is disposed between the transport body and the developing body and includes an opening allowing the developer supplied from the transport body to the developing body to pass and to which a sealing member sealing the opening is detachably attached; and a connection portion which extends to cross the opening at a spiral angle of the blade as viewed from the developing body toward the transport body and of which one end portion and the other end portion are connected to the attachment part.

The developing device includes a developing roller, a developer conveying unit, a developer discharge unit, and an air discharge port. The developer conveying unit includes a developing chamber provided with the developing roller and extending in a longitudinal direction of the developing roller, a stirring chamber arranged in parallel to the developing chamber, and a barrier wall having a first communication port and a second communication port, at respective ends in the longitudinal direction, to connect the developing chamber with the stirring chamber. The developer discharge unit extends from the developer conveying unit in the longitudinal direction of the developing roller and includes a developer discharge port to discharge excess developer. The air discharge port is to house a filter to filter a developer, the air discharge port being provided between the developer conveying unit and the developer discharge unit to discharge air in the developer conveying unit.

A toner sealing system is described including a seal having first and second alignment features. The seal is selectably installable on one of a first toner container of a first type and a second toner container of a second type. The first alignment feature is matable with a first corresponding alignment feature on the first toner container when the seal is installed on the first toner container for aligning the seal to the first toner container. The second alignment feature is matable with a second corresponding alignment feature on the second toner container when the seal is installed on the second toner container for aligning the seal to the second toner container. Embodiments include those wherein the first alignment feature does not align the seal to the second toner container, and the second alignment feature does not align the seal to the first toner container.

A powder transport apparatus includes a housing and first and second transport members. The housing includes first and second transport paths that are separated by a partition wall extending in one direction. The first and second transport paths are connected by first and second connection ports. The first and second connection ports are separated in the one direction with the partition wall interposed therebetween. The first transport member is provided in the first transport path. The first transport member transports powder. The second transport member is provided in the second transport path. The second transport member transports the powder. A transport force of the second transport member at a portion of the second transport member where the second transport member faces the first connection port is smaller than a transport force of the second transport member at a portion where the second transport member faces the partition wall.

A powder transport apparatus includes a housing and first and second transport members. The housing includes first and second transport paths that are separated by a partition wall extending in one direction. The first and second transport paths are connected by first and second connection ports. The first and second connection ports are separated in the one direction with the partition wall interposed therebetween. The first transport member is provided in the first transport path. The first transport member transports powder. The second transport member is provided in the second transport path. The second transport member transports the powder. A transport force of the second transport member at a portion of the second transport member where the second transport member faces the first connection port is smaller than a transport force of the second transport member at a portion where the second transport member faces the partition wall.

A developing apparatus for use in an image forming apparatus includes a developing frame, a rotatable developing member, a regulation blade to regulate developer borne on a developing member surface, and a seal member to prevent developer from leaking outside the developing frame. The regulation blade includes a support plate, a plate-shaped member, and a regulation member. The seal member is fixed to a facing surface of the plate-shaped member, is arranged at a plate-shaped member end portion, is arranged side by side with the regulation member in a rotational axis direction, contacts an end surface of the regulation member, and is disposed between the plate-shaped member and the developing member in a direction intersecting with the rotational axis direction. The plate-shaped member is welded to a region of the support plate excluding a region outside the end surface of the regulation member in the rotational axis direction.

A process cartridge includes a photosensitive member and a developing unit. The developing unit includes a frame to store toner, a developing roller to carry the toner, a side seal to contact an end portion of the developing roller and prevent the toner from leaking out, and a sealing sheet to contact a center portion of the developing roller and prevent the toner from leaking out. A toner receiving portion of the frame includes an opening facing the developing roller and is disposed on an upstream side of the side seal and a downstream side of a contact portion where the developing roller contacts the photosensitive member, and moreover is disposed at a position overlapping with the side seal. The developing unit includes a blocking member to block at least a part of the opening, and the blocking member is disposed between the opening and the developing roller.

A developing device includes a developing member to carry developer stored by a developing frame, and a regulating blade having a support plate fixed to the developing frame, a plate-like member, and a regulating member. One end portion of the plate-like member is opposed to the developing member, and the other end portion is welded to the support plate. The regulating member is fixed to a plate-like member surface, and contacts the developing member to regulate a developer thickness on a developing surface. The regulating member is provided with a recessed portion recessed at a regulating member end portion. The regulating member end portion is lower than a regulating member central portion. A plate-like member region welded to the support plate is located at the plate-like member other end portion and overlaps the regulating member central portion and the regulating member end portion at which the recessed portion is provided.

A process cartridge includes a first unit including an image bearing member to bear a developing agent image, a second unit including a development frame member in which a developing agent bearing member to bear a developing agent to be supplied to the image bearing member is supported, and a coupling portion that can couple the first and second units such that the second unit is swingable with the coupling portion as a rotation center. The development frame member includes a replenishing opening for the developing agent, and an elastically-deformable sealing member that seals the supply portion and the replenishing opening. As viewed along a compression direction of the sealing member, in a section orthogonal to a longitudinal direction of the process cartridge, the rotation center is disposed at a position overlapping with the sealing member.

A toner sealing system is described including a seal having first and second alignment features. The seal is selectably installable on one of a first toner container of a first type and a second toner container of a second type. The first alignment feature is matable with a first corresponding alignment feature on the first toner container when the seal is installed on the first toner container for aligning the seal to the first toner container. The second alignment feature is matable with a second corresponding alignment feature on the second toner container when the seal is installed on the second toner container for aligning the seal to the second toner container. Embodiments include those wherein the first alignment feature does not align the seal to the second toner container, and the second alignment feature does not align the seal to the first toner container.