An image forming apparatus includes a detachable unit attachable to and detachable from an apparatus body, a preceding unit configured to move relative to the apparatus body before the detachable unit is attached to or detached from the apparatus body, and an adhesion-suppressing component provided on the preceding unit and configured to suppress adhesion of floating matter in the apparatus body to a grip of the detachable unit by covering the grip.

A transfer device includes: a transfer drum that has a groove-like recess extending in an axial direction in an outer circumferential portion thereof, rotates about an axis thereof, and comes into contact with a medium being transported at a portion thereof on an upstream side of the recess in a rotation direction; a nip member, the nip member and the transfer drum forming therebetween a nip part where the medium is nipped; an application member that applies a voltage to the nip part where the medium is nipped, so that an image is transferred to the medium; and a contact mechanism that causes the nip member to come into contact only with a portion on the upstream side of the recess in the transfer drum in the rotation direction at a transfer-start time when the transfer of the image to the medium starts.

In an example of the disclosure, service rotation of a drum along a longitudinal axis of the drum is caused. The service rotation is to apply a centrifugal force upon a liquid held by the drum. The centrifugal force pushes gas bubbles in the drum away from a curved surface of the drum and towards the longitudinal drum axis. The gas bubbles evacuate from the drum via an outlet tube positioned adjacent to the longitudinal drum axis. A production rotation of the drum is caused after the service rotation.

In an example of the disclosure, service rotation of a drum along a longitudinal axis of the drum is caused. The service rotation is to apply a centrifugal force upon a liquid held by the drum. The centrifugal force pushes gas bubbles in the drum away from a curved surface of the drum and towards the longitudinal drum axis. The gas bubbles evacuate from the drum via an outlet tube positioned adjacent to the longitudinal drum axis. A production rotation of the drum is caused after the service rotation.

An image forming apparatus includes a unit horizontally insertable and drawable with respect to a main body frame, and a lock mechanism for the unit. The lock mechanism includes a lock member which has an engagement projection engageable with an engaged portion formed in the main body frame, and a biasing member which biases the lock member in a first direction toward engagement of the engagement projection with the engaged portion. Along with insertion of the unit, the lock member moves in a second direction, and when the unit is inserted to a predetermined position, biasing force of the biasing member causes the lock member to move in the first direction and the engagement projection engages with the engaged portion. By moving the lock member in the second direction, engagement between the engagement projection and the engaged portion is released to make it possible to draw the unit.

An image forming apparatus includes a photosensitive member, a transfer unit having a transfer belt, a primary transfer roller, a secondary transfer inner roller below the primary transfer roller in a vertical direction, and a stretching roller, a secondary transfer outer roller, a support unit, and an air duct provided in the transfer unit. The secondary transfer outer roller faces the secondary transfer inner roller via the transfer belt and forms a nip portion for secondarily transferring a toner image on the transfer belt to a sheet. The air duct is located downstream of the nip portion in a sheet conveyance direction and below a portion of the transfer belt stretched between the secondary transfer inner roller and the stretching roller in the vertical direction. The air duct includes an air intake port and moves with the transfer unit with movement of the transfer unit from the support unit.

An image forming apparatus includes an main body, a processing unit, and a pressing member. The main body includes a transfer belt wound around a plurality of rollers. The processing unit can be inserted into and removed from the main body. The processing unit includes a drum that faces the transfer belt in a state of being inserted into the main body. The processing unit forms an image on the surface of the drum. The pressing member is provided on the main body and includes a contacted portion and a contacting portion. The contacted portion comes into contact with the processing unit when the processing unit is inserted into and removed from the main body. The contacting portion comes contact with the transfer belt due to contact with the processing unit to push the transfer belt in a direction away from the processing unit.

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.

A transfer device includes: a transfer drum that has a groove-like recess extending in an axial direction in an outer circumferential portion thereof, rotates about an axis thereof, and comes into contact with a medium being transported at a portion thereof on an upstream side of the recess in a rotation direction; a nip member, the nip member and the transfer drum forming therebetween a nip part where the medium is nipped; an application member that applies a voltage to the nip part where the medium is nipped, so that an image is transferred to the medium; and a contact mechanism that causes the nip member to come into contact only with a portion on the upstream side of the recess in the transfer drum in the rotation direction at a transfer-start time when the transfer of the image to the medium starts.

An image forming apparatus for forming an image on a sheet includes a rotatable image bearing member, a transfer roller, a fan, and a duct. The duct extends in a parallel direction to a shaft direction of the transfer roller and includes an inflow port to guide air. The duct further includes, in an area opposing the transfer roller, a first opening portion that is provided at a position closer to a first end side of the duct than to a second end side of the duct, and a second opening portion that is provided at a position closer to the second end side than to the first end side, in the parallel direction. The air supplied to the duct by the fan through the inflow port passes through the first opening portion and the second opening portion, and is supplied to the transfer roller.