A drive transmission device, which is included in an image forming apparatus and detachably attached to an apparatus body configured to include a driven body to which a driving force is transmitted, includes a first opposing body and a second opposing body disposed facing each other and forming a gap therebetween, a gear rotatably disposed in the gap formed between the first opposing body and the second opposing body, and a rotary shaft configured to receive the driving force from a drive source and rotate in the gap. One rotational axial end of the rotary shaft being passed through the second opposing body and rotatably supported by the second opposing body in the gap.

Disclosed in the present invention is a developing cartridge, which is detachably mounted in an image forming device, comprising: a housing; a developing roller rotatably supported by the housing, the developing roller rotating about an axis extending in a first direction; a supply roller rotatably supported by the housing and configured to convey a developer to the developing roller, the supply roller having a supply roller shaft made of metal; a driving gear disposed on a driving side of the housing in the first direction; and an electrode electrically connected to the developing roller shaft, comprising a first part, a second part, and an intermediate electrical connection part connecting the first part and the second part; wherein the first part is located on an opposite side of the driving side of the housing, the second part is located on the driving side of the housing, and the opposite side of the driving side and the driving side are opposite ends of the housing in the first direction; and the second part is simultaneously in contact with the supply roller shaft and the developing roller shaft.

An image forming apparatus includes a power transmission member, a bias portion, a cam, and an interlocking mechanism. The power transmission member is displaceable between connected and released positions where the power transmission member is respectively connected to and disconnected from the detachable portion, and transmits the driving force of a drive portion to the detachable portion while connected to the detachable portion. The bias portion biases the power transmission member in a first direction to the connected position. The cam pivots from a first position to a second position to displace the power transmission member from the connected position to the released position, and is biased by the bias portion in a second direction to the first position when in the second position. The interlocking mechanism causes the cam to pivot from the first to the second position as a cover member changes its state from closed to open.

A process cartridge including: a photosensitive member cartridge including a photosensitive member; and a developing cartridge including a developer carrier. The developing cartridge further includes: an inputting portion; a first cover; and a second cover. The first cover has a first engagement portion configured to move the developer carrier away from the photosensitive member. The first engagement portion is positioned between an axis of the developer carrier extending in an axial direction and an axis of the inputting portion extending in the axial direction, when projected in the axial direction. The second cover has a second engagement portion configured to move the developer carrier away from the photosensitive member. The second engagement portion is positioned between the axis of the developer carrier and the axis of the inputting portion, when projected in the axial direction.

A developing cartridge includes: a developing roller; a coupling for rotating the developing roller; a shaft; and a clutch. The developing roller is rotatable about a first axis extending in an axial direction. The coupling is rotatable about a second axis extending in the axial direction. The shaft rotatably supports the coupling. The clutch is rotatable together with the coupling about the shaft in a case where the coupling rotates in a first rotational direction. In a case where the coupling rotates in a second rotational direction opposite to the first rotational direction, the clutch engages with a portion of the shaft and the clutch and the coupling do not rotate.

An image forming apparatus includes a cartridge including a portion-to-be-positioned, and an apparatus main body on which the cartridge is mounted in a mounting direction. The apparatus main body includes a positioning portion and a regulating portion. The positioning portion positions the cartridge by engaging with the portion-to-be-positioned. The regulating portion is provided on an upstream side of the positioning portion in the mounting direction. The cartridge includes a portion-to-be-regulated provided on an upstream side of the portion-to-be-positioned in the mounting direction. The portion-to-be-positioned engages with the regulating portion before engaging with the positioning portion, to regulate movement of the cartridge in the direction orthogonal to the mounting direction. The portion-to-be-regulated engages with the regulating portion before the portion-to-be-positioned engages with the positioning portion, to regulate movement of the cartridge in the direction orthogonal to the mounting direction.

[Problem to be solved] To further develop conventional technique. [Solution] a cartridge includes a casing, a photosensitive drum and a coupling.

the coupling includes a driving force receiving portion for receiving a driving force by engagement with a driving force application member, a braking force receiving portion for receiving in braking force by engagement with a braking force application member, and a guide for moving the braking force application member relative to the driving force application member.

A motor control apparatus excites an excitation phase targeted for excitation among a plurality of excitation phases of a motor. The motor control apparatus, in a state in which a rotor of the motor is stopped, excites an excitation phase corresponding to a stop position of the rotor among the plurality of the excitation phases, and measures a physical quantity which changes in accordance with an inductance of at least one of a plurality of coils configuring the plurality of excitation phases. The motor control apparatus estimates a temperature of the rotor from a measurement value of the measured physical quantity, and decides a parameter value for control of the motor based on the estimated temperature.

An image forming apparatus includes drum shafts supported by a main body, drum cartridges insertable and removable in an axial direction, a regulation side plate having bearings, a projecting portion provided to one of the regulation side plate and the main body, a fitting portion, and an urging force imparting portion. The urging force imparting portion is provided to the regulation side plate in an array direction of the bearings to impart an urging force that urges the regulation side plate toward the main body. At least a part of the urging force imparting portion is provided at a position for imparting the urging force on, with respect to the bearings, a side opposite to a position at which one of the projecting portion and the fitting portion is provided, in a direction orthogonal to the array direction of the bearings and the axial direction of each drum shaft.

An image forming apparatus includes a developing roller, a photo-interrupter, and a separation mechanism. The developing roller is movable between a contact position and a separated position. The photo-interrupter includes a light emitting element and a light receiving element. The separation mechanism includes a cam configured to move the developing roller between the contact position and the separated position. The cam includes a phase detection wall extending in a circumference direction. The phase detection wall has a first slit and a second slit. The first slit allows the light emitted from the light emitting element to pass therethrough when the developing roller is at the separated position. The second slit allows the light emitted from the light emitting element to pass therethrough when the developing roller is at the contact position. A size of the first slit in the circumferential direction is different from that of the second slit.