An image forming apparatus includes a plurality of photosensitive drums, an intermediate transfer belt, a cleaning member to contact an inner surface of the intermediate transfer belt to remove impurities from the intermediate transfer belt, a storage member including a storage to accommodate the impurities removed by the cleaning member, and a shutter movable to a first location at which the storage is opened and a closing location at which the storage is closed.

An image forming apparatus includes a motor, an image formation-transfer section, a switching mechanism, a fixing section, and a controller. The motor generates driving force. The image formation-transfer section state-changes between a first contact state and a first separate state by the driving force. The switching mechanism transmits and cuts off the driving force to the image formation-transfer section. The fixing section includes first and second rotating members, and state-changes between a second contact state and a second separate state by the driving force. The controller controls the motor and the switching mechanism and thereby causes part or all of a first period, in which the fixing section state-changes from the second separate state to the second contact state, and part or all of a second period, in which the image formation-transfer section state-changes from the first separate state to the first contact state, to overlap each other.

An image forming apparatus includes an image bearing member, a developing member, a controller configured to carry out switching control between a first state in which the developing member is caused to act on the image bearing member and a second state in which the developing member is not caused to act on the image bearing member, a transfer member, and a detector configured to read density information of the recording material. The controller detects a fog density on the basis of a difference intensity information between a fog non-occurrence region of a non-image region of the recording material in the second state and a fog occurable region of the non-image region of the recording material in the first state.

An image forming apparatus that has a transfer device that includes an intermediate transfer belt that is tensioned by a plurality of support rollers, a secondary transfer roller that faces one of the support rollers via the intermediate transfer belt, a cam that adjust a pressing force that presses the intermediate transfer belt by the secondary transfer roller, a motor that drives the cam, and a conveyor that conveys a recording medium to a transfer nip formed between the intermediate transfer belt and the secondary transfer roller is provided with a controller that controls an operation of the motor. The controller executes first control of operating the motor with a constant torque and stopping the motor when a rotation angular speed of the motor is less than or equal to a first threshold and second control of operating the motor at a predetermined timing to adjust a transfer nip amount.

An imaging device prints in color and monochromatically, such as black-only. It has a plurality of photoconductive drums, one each for black toner and at least one colored toner. The drums contact and rotate with an intermediate transfer member (ITM) to transfer images at a first transfer. During black-only imaging, the photoconductive drum for the black toner rotates with the ITM at process speed while the drum for the at least one colored toner rotates at less than process speed, often substantially less. The technique reduces consumption of colored toner during black-only imaging and minimizes charge build-up on the drum for the colored toner.

An image forming apparatus includes an endless belt; an image bearing member that bears a toner image and contacts with the outer circumferential surface of the belt at a transfer position for transferring the toner image to the belt, the transfer position being disposed downstream; a transfer roller configured to transfer the toner image from the image bearing to the belt and contact with an inner circumferential surface of the belt at a contact position, the contact position not overlapping with the transfer position as viewed from the thickness direction of the belt; a biasing member that biases the transfer roller toward the inner circumferential surface of the belt, and a position of the transfer roller is set to a balanced position between a biasing force by the transfer roller pressing the inner circumferential surface of the belt and the drag received by the transfer roller from the belt.

An imaging device prints in color and monochromatically, such as black-only. It has a plurality of photoconductive drums, one each for black toner and at least one colored toner. The drums contact and rotate with an intermediate transfer member (ITM) to transfer images at a first transfer. During black-only imaging, the photoconductive drum for the black toner rotates with the ITM at process speed while the drum for the at least one colored toner rotates at less than process speed, often substantially less. The technique reduces consumption of colored toner during black-only imaging and minimizes charge build-up on the drum for the colored toner.

A transfer device includes a transfer drum that rotates in conjunction with a fixing roller, a transfer belt that transfers an image onto a medium while rotating along with the transfer drum in a state where the medium is nipped between the transfer belt and the transfer drum, a pressing member that is disposed in a space enclosed by the transfer belt, and a switching unit that moves the pressing member and switches between a pressed state in which the transfer belt is pressed against the transfer drum and a separated state in which the transfer belt is separated from the transfer drum.

A control unit first drives a photosensitive drum at a normal speed that is faster than a low speed, and the control unit subsequently changes the drive speed of the photosensitive drum from the normal speed to the low speed after a transfer belt is brought into contact with the photosensitive drum that is driven at the normal speed.

An image forming apparatus is configured to, based on a reading result of a test image, generate data that is used to adjust image forming positions of toner images to be formed by an image forming unit, control an image forming position of a first toner image to be formed by the image forming unit in a first contact state based on first data, the first toner image being transferred to a first sheet, and control an image forming position of a second toner image to be formed by the image forming unit in a second contact state based on second data that is different from the first data, the second toner image being transferred to a second sheet, wherein a type of the second sheet is the same type as the type of the first sheet.