A developing device includes a developer holder that holds a developer containing toner and carrier and being supplied to an image holder forming an electrostatic latent image; and a conveyance section that agitates and conveys the developer flowing in from an inlet using a rotation member to cause the developer to flow out toward the developer holder at an outlet, that includes, as a part constituting a portion of the rotation member, a first blade part for conveyance to the outlet and a second blade part for conveyance in a direction opposite to the outlet, and in which a greater amount of the developer flows in from the inlet than the developer flows out from the outlet.

A developing device in an apparatus main body of an image forming device includes a developing container having an accommodation chamber to accommodate a developer and a developing chamber communicating with the accommodation chamber through a communication port, with the accommodation chamber and developing chamber being integrally formed such that the developing chamber is disposed below the accommodation chamber in a state where the developing device is in use in the apparatus main body. The developer container includes an abutting surface which forms the accommodation chamber and abuts a second end portion of a sheet opposite to a first end portion such that the sheet is maintained in a bent state until the second end portion of the sheet passes in front of an upstream end of the communication port in a rotation direction of the conveyance member and then reaches a light guide provided in the accommodation chamber.

According to an embodiment, a developer-supplying container includes a container and a paddle. The container includes an opening for supplying the image forming apparatus with developer contained in the container. The paddle conveys the developer to the opening by rotating within the container. The paddle includes a first arm. The first arm has a shape that is wider on an upstream side in a direction of the rotation of the paddle and narrower toward a downstream side. In addition, the first arm is disposed such that a narrowest portion of the first arm is located at the same position as the opening in a direction of a shaft.

A replaceable unit for an electrophotographic image forming device according to one example includes a housing having a toner reservoir. An electrical connector mounted on the housing is movable between a retracted position and an operative position. The electrical connector includes an electrical contact for contacting a corresponding electrical contact in the image forming device. The electrical contact is electrically connected to processing circuitry on the housing. In the retracted position, the electrical connector is tucked into a portion of the housing. In the operative position, the electrical connector is exposed to permit the electrical contact to contact the corresponding electrical contact in the image forming device. A linkage is operatively connected to the electrical connector and includes an engagement surface accessible on an exterior of the housing to receive an actuation force. Movement of the actuation linkage moves the electrical connector between the retracted position and the operative position.

The developing device includes a first rotatable member, a first magnet, a second rotatable member, and a second magnet. When a position where on a second rotatable member surface, a magnetic flux density of the receiving pole is maximum is a point T, of positions each where the magnetic flux density of the receiving pole is a half value of the maximum, the position on an upstream side is a point Hu, the position, the position on a downstream side is a point Hd, an angle formed by a rectilinear line L20 connecting a rotation center R2 of the second rotatable member and the point T and a rectilinear line L21 connecting the rotation center R2 and the point Hu is w21, and an angle formed by L20 and a rectilinear line L22 connecting R2 and Hd is w22, the following relationship is satisfied: w22w210.

A device for use in an apparatus main body of an image forming apparatus includes first and second chambers accommodating a developer and which is provided with a communicating port through which the first and second chambers communicate, a roller to bear the developer accommodated in the second chamber, and a conveyance member to convey, by being rotated, the developer in the first chamber toward the second chamber through the communication port. A detecting member is provided above the communication port. The conveyance member and the container are configured so that a second end portion of a sheet is maintained in a bent state by contacting an inner surface constituting the first chamber of the container until the second end portion of the sheet passes in front of an upstream end of the communication port in a rotation direction of the conveyance member and then reaches the detecting member.

A drum cartridge includes: a drum frame to which a developing cartridge including a storage medium having an electrical contact surface is detachably attachable; a photosensitive drum; a transfer roller; and a conveying roller. The drum is rotatable about a first axis extending in a first direction and positioned at one end portion of the frame in a second direction. The transfer roller is rotatable about a second axis extending in the first direction and in contact with the drum. The conveying roller is rotatable about a third axis extending in the first direction and separated from the transfer roller in the second direction. A first opening of the frame is positioned between the transfer roller and the conveying roller in the second direction. The electrical contact surface is exposed to an outside through the first opening in a case where the developing cartridge is attached to the frame.

The developing device includes a development container, a developer carrier, and a toner trapping mechanism. The development container includes a first conveyance chamber and a second conveyance chamber placed in parallel juxtaposition and communicated with each other at their longitudinal both end portions, and the development container contains a toner-containing developer to be fed to an image carrier. The toner trapping mechanism includes a duct, an air inlet port, a trapping filter, and a fan. The duct is connected to the second conveyance chamber, and allows air present in the second conveyance chamber to flow therethrough. The development container has an air vent opened in the first conveyance chamber and communicated with outside of the development container.

A drum cartridge includes: a drum frame to which a developing cartridge including a storage medium having an electrical contact surface is detachably attachable; a photosensitive drum; a transfer roller; and a conveying roller. The drum is rotatable about a first axis extending in a first direction and positioned at one end portion of the frame in a second direction. The transfer roller is rotatable about a second axis extending in the first direction and in contact with the drum. The conveying roller is rotatable about a third axis extending in the first direction and separated from the transfer roller in the second direction. A first opening of the frame is positioned between the transfer roller and the conveying roller in the second direction. The electrical contact surface is exposed to an outside through the first opening in a case where the developing cartridge is attached to the frame.

A developer container is used, including developing roller, rotatable developer supplying roller, developing chamber provided with the developing roller and the supplying roller, developer housing configured to store the developer, and having opening that communicably connects the developer housing and the developing chamber, and stirring member provided inside the developer housing and configured to be rotatable in the same direction as the direction in which the supplying roller is rotated. A height of a rotation shaft of the stirring member is equal to or higher than a height of the rotational shaft of the supplying roller. The opening of the housing is provided with a sealing member. The sealing member is bonded on the upstream and downstream sides of the opening in the rotating direction of the stirring member, and is configured to peel off from the upstream side toward the downstream side.