An imaging system includes a casing with a developing chamber, a developing roller which is located inside the developing chamber and which carries a toner, and a conveying path which is located adjacent to the developing chamber inside the casing and is used to circulate the toner and to supply the toner to the developing roller. A discharge path includes an inlet, an outlet, and an intermediate portion between the inlet and the outlet. The inlet communicates with the developing chamber in the casing and is located outside the conveying path. The outlet is located between the developing roller and a photoreceptor. The intermediate portion is located outside the casing.

A first replaceable unit is provided for use with a second replaceable unit in an electrophotographic image forming device. The first replaceable unit includes a latch movable between a latching position for latching the first replaceable unit to the second replaceable unit and an unlatching position for permitting the first replaceable unit to separate from the second replaceable unit. The latch is positioned to contact a latch catch on the second replaceable unit in order to prevent the first replaceable unit from separating from the second replaceable unit when the first replaceable unit is mated with the second replaceable unit and the latch is in the latching position. The latch includes a cam follower surface for contacting a camming surface on the second replaceable unit during mating of the first replaceable unit with the second replaceable unit to cause the latch to move toward the latching or unlatching position.

An image forming apparatus includes a main body casing, a drum cartridge, a developing cartridge and an intermediate transfer belt. The drum cartridge is removably insertable into to the main body casing in a first direction. The developing cartridge is removably insertable into the main body casing in the first direction. The drum cartridge includes a first handle. The first handle has a first recess having a first hollow. The developing cartridge includes a second handle. The second handle has a second recess having a second hollow.

A print material cartridge may include a hopper to maintain an amount of print material therein; and an atmospheric pressure seal to seal the hopper from atmosphere; wherein a pressure within the hopper and sealed by the atmospheric pressure seal is lower than atmosphere.

An image forming apparatus includes: a housing; a drawer; and first and second process cartridges attachable to the drawer. The first process cartridge includes a first drum cartridge including a first photosensitive drum and a first developing cartridge including a first developing roller. When attached to the first drum cartridge, the first developing cartridge is movable between a first position where the first developing cartridge is detachable from the first drum cartridge and a second position where the first developing cartridge is not detachable from the first drum cartridge. In a state where the first and second process cartridges are attached to the drawer at positions adjacent to each other, the first developing cartridge comes into contact with the second process cartridge during movement of the first developing cartridge from the second position to the first position before the first developing cartridge reaches the first position.

A developing cartridge includes: a casing; a developing roller; a shaft; and a cam. The casing is configured to accommodate developer therein. The developing roller is rotatable about a first axis extending in an axial direction. The shaft extends along a second axis extending in the axial direction. The shaft is movable along the second axis. The cam is movable along the second axis in response to axial movement of the shaft. The cam has a cam surface non-parallel with the second axis.

An image forming apparatus includes an accommodating portion, a motor, and a development sensor. In the accommodating portion, a replacement developing component is fitted. The replacement developing component is fitted with a rotary member including an operating member, and stores toner. The motor rotates the rotary member on the replacement developing component fitted in the accommodating portion. When a new replacement developing component is fitted, the development sensor is not in contact with the operating member before the motor rotates the rotary member and is in contact with the operating member on the rotary member that has moved as the motor rotates. The development sensor outputs a first level when in contact with the operating member and outputs a second level when not in contact with the operating member.

A first replaceable unit is provided for use with a second replaceable unit in an electrophotographic image forming device. The first replaceable unit includes a latch movable between a latching position for latching the first replaceable unit to the second replaceable unit and an unlatching position for permitting the first replaceable unit to separate from the second replaceable unit. The latch is positioned to contact a latch catch on the second replaceable unit in order to prevent the first replaceable unit from separating from the second replaceable unit when the first replaceable unit is mated with the second replaceable unit and the latch is in the latching position. The latch includes a cam follower surface for contacting a camming surface on the second replaceable unit during mating of the first replaceable unit with the second replaceable unit to cause the latch to move toward the latching or unlatching position.

An image forming apparatus, including a process cartridge and a main body with an opening and a cartridge supporter is provided. The process cartridge includes a drum cartridge; a toner cartridge attachable to the drum cartridge; and a switching member switchable states in the process cartridge between a first state, wherein detachment of the toner cartridge is restricted, and a second state, wherein the toner cartridge is released from the restriction. The cartridge supporter is movable between a first position, wherein the cartridge supporter supports the process cartridge to be placed entirely in an inner space in the main body on an inner side of the opening, and a second position, wherein the cartridge supporter supports the process cartridge to be at least partly placed outside the inner space. When the cartridge supporter is in the second position, the switching member is at least partly placed outside the inner space.

Movement and/or urging of a developer carrying memer is carried out with high precision. A cartridge that is mountable to an apparatus main assembly of an image forming apparatus, the cartridge includes a developing roller; a frame supporting the developing roller; a movable part movably supported by the frame and movable to a first position and to a second position relative to the frame; and an elastic part provided between the frame and the movable part to urge the movable part. The movable part includes a first force receiving part that receives force from the apparatus main assembly, in a direction of moving from the first position to the second position, and a second force receiving part that receives force from the apparatus main assembly, in a direction of moving from the second position to the first position. When the movable part receives force from the apparatus main assembly at the first force receiving part and is at the second position, the movable part receives urging force from the elastic part in a direction of moving the movable part from the second position to the first position.