A developing device includes a developer container to contain developer including toner and magnetic carrier, the developer container; a developer bearer to carry, by rotation, the developer to a developing range facing a latent image bearer; a communication opening in a wall defining the developer container; a toner conveyance passage connected to the communication opening; and a cylindrical magnet having a magnetic pole arrangement parallel to an axis of the cylindrical magnet. The cylindrical magnet is disposed to enclose a space overlapping with the communication opening on a cross section perpendicular to the axis of the cylindrical magnet.

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.

Provided is an image forming apparatus including an image carrier, an exposure device, a developing device that supplies a developer to form a toner image, and a hardware processor that controls the image carrier, the exposure device, and the developing device. The image forming apparatus further includes a fume prevention plate that covers a part of an internal space of the developing device where the developing roller is disposed and the developer is stored and that prevents the developer from scattering outside from the internal space, a suction duct, and an air suction device. One end of the suction duct is connected to the internal space and another end of the suction duct is connected to the air suction device. The fume prevention plate includes a movable portion. A position of the movable portion can be changed between a first position and a second position different from the first position.

A developing device includes a developing case, a filter, and a filter holder. The developing case stores developer inside to develop a latent image formed on a surface of an image bearer and has an opening portion that communicates between an inside and an outside of the developing device. The filter has a lower weight density per unit volume at a first side of the filter facing the inside of the developing device than a weight density per unit volume at a second side of the filter facing the outside of the developing device. The filter holder is detachably attached to the opening portion of the developing case with the filter held by the filter holder.

An image forming apparatus (1) includes a casing (21) having a toner conveyance path (34); a screw (24) conveying a toner in the toner conveyance path (34) in a predetermined conveyance direction; and a downstream side bearing (25) rotatably supporting a downstream side end portion of the screw (24) in the conveyance direction, wherein the screw (24) includes: a shaft (51) extending in the conveyance direction; and a spiral fin (52) provided around an outer circumferential face of the shaft (51), the shaft (51) has a downstream side insertion part (54) inserted into the downstream side bearing (25), and the downstream side insertion part (54) has an outer diameter larger than an outer diameter of a downstream side end portion of the fin (52) in the conveyance direction.

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.

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 developing roller, a housing, and a film member. A side opening provided in the housing communicates with a suction device at an end in a rotation axis direction of the developing roller. A downstream cover portion of the housing covers the developing roller from a downstream side in a rotation direction of the image carrying member. Concave portions of the downstream cover portion and a portion of a film member bonded to the downstream cover portion form ducts that communicate from openings facing the image carrying member to the side opening.

A developing device includes a developing container, a developer carrier, a seal member, and a pair of pressing members. The developing container has an opening. The seal member includes a contact end part that makes contact with an entire region of an outer circumferential surface of the developer carrier in its rotary shaft direction and is one of end edges of the seal member in a longitudinal direction thereof on a side near the developer carrier and an interposed end part that is interposed between each of both end parts of the developer carder and a corresponding one of the pressing members and is an end edge of the seal member orthogonal to the contact end part, and a chamfered shape is formed at a corner between the contact end part and the interposed end part.

A toner cartridge according to one embodiment includes an outlet port positioned on the front of a housing for exiting toner from the toner cartridge. The toner cartridge includes an engagement member having a first engagement surface and a second engagement surface. The first engagement surface is positioned proximate the rear of the housing to receive an actuation force in a frontward direction of the housing at the rear of the housing. The second engagement surface is positioned proximate the front of the housing below the outlet port. The engagement member is movable from a first position to a second position upon receiving the actuation force. As the engagement member moves from the first position to the second position, the second engagement surface moves in the frontward direction and protrudes from the front of the housing with at least a portion of the front of the second engagement surface unobstructed.