An image forming apparatus includes an image forming portion, a belt unit including a cleaning unit and an opposing roller, and a swinging mechanism. The swinging mechanism includes a swingable member which is provided in a position different from a rotation center of the opposing roller while holding the opposing roller and the cleaning unit without changing a relative positional relationship between the opposing roller and the cleaning unit and which is swingable about a swing axis.

An image forming apparatus includes: an image carrier body to be transported; an image forming unit that forms an image on the image carrier body; a change roller that is in contact with an inner peripheral surface of the image carrier body so as to be rotatable around a rotation axis and that is capable of changing an angle of the rotation axis with respect to a width direction of the image carrier body; a flywheel provided at the change roller; and a driving mechanism that applies a driving force for changing an angle of the rotation axis with respect to the width direction to an applied portion that moves together with the change roller. A direction of the driving force applied to the applied portion by the driving mechanism is opposite to a direction in which the applied portion moves due to gravity acting on the flywheel.

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.

An image forming apparatus includes: an annular endless belt; a drive roller, around which the endless belt is wound and which moves the endless belt; a first tension roller, around which the endless belt moved by the drive roller is wound; a biasing mechanism connected to the first tension roller and including an elastic member that applies a tension to the endless belt via the first tension roller; a second tension roller, around which the endless belt moved by the drive roller is wound at a different position from the first tension roller; and a moving mechanism connected to the second tension roller to move the second tension roller in directions closer to and away from the endless belt. A range of adjustment of a circumferential length of the endless belt by the moving mechanism is larger than a range of adjustment of the circumferential length of the endless belt by the biasing mechanism.

An image forming apparatus includes: a belt to be transported; an image forming body that forms an image on the belt or a recording medium that is transported by the belt; a moving mechanism that moves the belt in a movement direction extending in a thickness direction of the belt; a rotational member including a rotation shaft extending in the movement direction and a contact portion that is rotatable around the rotation shaft and that is in contact with a side surface of the belt regardless of a position of the belt in the movement direction; an acquirer that acquires a physical amount that changes due to rotation of the contact portion around the rotation shaft when the belt moves in a width direction; and a detector that detects a movement amount of the belt in the width direction based on the physical amount acquired by the acquirer.

A motor control apparatus includes: a switching power supply; a first motor configured to operate with a voltage from the switching power supply; and a control unit configured to control the first motor, wherein the control unit is further configured to cause the switching power supply to supply power of the switching power supply to a load other than the first motor before detecting an initial position of a rotor of the first motor using a current flowing through the first motor.

An image forming apparatus includes: a belt to be transported; an image forming body that forms an image on the belt or a recording medium that is transported by the belt; a moving mechanism that moves the belt in a movement direction extending in a thickness direction of the belt; a rotational member including a rotation shaft extending in the movement direction and a contact portion that is rotatable around the rotation shaft and that is in contact with a side surface of the belt regardless of a position of the belt in the movement direction; an acquirer that acquires a physical amount that changes due to rotation of the contact portion around the rotation shaft when the belt moves in a width direction; and a detector that detects a movement amount of the belt in the width direction based on the physical amount acquired by the acquirer.

A transport device includes: a rotating member that rotates; a circulating member that is loop-shaped and wrapped around the rotating member, the circulating member being circulated by rotation of the rotating member; and a pair of pinching members attached to an attachment portion of the circulating member and circulated together with the circulating member, the pair of pinching members changing from a separated state, in which the pair of pinching members are separated from each other, to a closely positioned state to pinch a transport object that has entered a space between the pair of pinching members in the separated state. The attachment portion of the circulating member is in contact with the rotating member when the transport object starts to enter the space between the pair of pinching members in the separated state.

A biasing force adjusting device includes a roller, a roller holder, a first biasing member, and a second biasing member. The roller faces a mover. The roller holder holds the roller and is displaceable with respect to the mover. The first biasing member applies a first biasing force to the roller holder to press the roller against the mover. The second biasing member applies a second biasing force greater than the first biasing force to the roller holder to press the roller against the mover.

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.