Abstract: An edge regulating member provided in a belt rotation device that tensions a belt via a belt tensioning roller and rotates the belt in a rotation direction includes a body that comes into contact with an inner surface of the belt and a regulating portion that extends, at a position adjacent to the body, further outward in a radial direction of the belt tensioning roller than the body, and comes into contact with an edge of the belt. Tension of the belt acting on the body while the inner surface of the belt is in contact with the body causes the regulating portion to tilt, turned outward in the rotation axis direction from a fold-back portion of the belt toward an upstream side in the rotation direction.

Abstract: A rotational force transmission device includes a transmission mechanism disposed on an input gear, and a ratchet member disposed on an output gear. The transmission mechanism includes a first sleeve having a first interlocker, a second sleeve having a second interlocker that engages with the first interlocker with a rotation clearance in the circumferential direction, and a coil spring disposed between the first and second sleeves. When a drive source is stopped, the second sleeve can idly rotate within the rotation clearance between the first and second interlockers. The first sleeve has a first retainer, and the second sleeve has a second retainer engaging with the first retainer in the axial direction. The first sleeve, the second sleeve, and an urging member are unitized by the engagement of the first and second retainers.

Abstract: A conduction mechanism includes: a conductive bearing that rotatably supports a rotary shaft; a non-conductive axial positioner that has a cylinder externally fitted to the bearing; and a contact terminal attached to an outer circumferential surface side of the cylinder. The cylinder has a slit, and the contact terminal has an abutment piece that is exposed to an inner circumferential surface side of the cylinder from the slit and abuts an outer circumferential surface of the bearing.

Abstract: A driving force transmission mechanism is a mechanism for transmitting rotational force of the second rotor having a driving-side coupling to a first rotor having a driven-side coupling. The driving-side coupling includes a body and a plurality of second engaging members engaging with first engaging members of the driven-side coupling, each of the plurality of second engaging members has at an abutting point on an abutting surface of a corresponding first engaging member a first inclined surface inclined so as to be away from a rotation axis of the body from a downstream side toward an upstream side in a rotation direction of the body.

Abstract: In a lock member of a pull-out lock device, while two adjacent sheet containers are both located at an accommodated position in an image-forming apparatus main body, a contact member is in contact with one of the sheet containers and thus the lock member rotates around a rotation axis, and a lock moves to an unlock position to allow the other sheet container to move in a pull-out direction, and while the other sheet container is located at the accommodated position and the one of the sheet containers is pulled out from the accommodated position in the pull-out direction and thus the contact between the one of the sheet containers and the contact member is removed, the lock member rotates around the rotation axis and the lock moves to a lock position to prohibit the other sheet container from moving in the pull-out direction.

Abstract: A conduction mechanism includes: a conductive bearing that rotatably supports a rotary shaft; a non-conductive axial positioner that has a cylinder externally fitted to the bearing; and a contact terminal attached to an outer circumferential surface side of the cylinder. The cylinder has a slit, and the contact terminal has an abutment piece that is exposed to an inner circumferential surface side of the cylinder from the slit and abuts an outer circumferential surface of the bearing.

Abstract: A driving force transmission mechanism is a mechanism for transmitting rotational force of the second rotor having a driving-side coupling to a first rotor having a driven-side coupling. The driving-side coupling includes a body and a plurality of second engaging members engaging with first engaging members of the driven-side coupling, each of the plurality of second engaging members has at an abutting point on an abutting surface of a corresponding first engaging member a first inclined surface inclined so as to be away from a rotation axis of the body from a downstream side toward an upstream side in a rotation direction of the body.

Abstract: An image forming apparatus comprises a housing including a resin frame. The resin frame is divided in a sheet feeding direction to include a conveyance frame, a process frame and a fixation frame. Moreover, the image forming apparatus comprises a driving unit and a drive frame. The driving unit is attachably and detachably provided in the drive frame, and applies a rotational driving force to rotating bodies. The drive frame is positioned with respect to the conveyance frame or the process frame, supports the rotating bodies, and has an attaching portion for the driving unit. Moreover, the drive frame is attached to one surface of the resin frame.

Abstract: An image forming apparatus comprises a housing including a resin frame. The resin frame is divided in a sheet feeding direction to include a conveyance frame, a process frame and a fixation frame. Moreover, the image forming apparatus comprises a driving unit and a drive frame. The driving unit is attachably and detachably provided in the drive frame, and applies a rotational driving force to rotating bodies. The drive frame is positioned with respect to the conveyance frame or the process frame, supports the rotating bodies, and has an attaching portion for the driving unit. Moreover, the drive frame is attached to one surface of the resin frame.

Abstract: A secondary transfer portion includes a transfer roller, a fixing member, a movable member, and a detector. The transfer roller is configured to rotate about an axis thereof when the secondary transfer portion is attached to an apparatus body. The fixing member is fixed to the axial end portion of the transfer roller. The movable member is caught on the fixing member. The detector is configured to indicate different detection states depending on a position of the movable member. The fixing member and the movable member are connected to each other through a guide mechanism (a guide groove and a guide protrusion) that is configured to move the movable member in an axial direction of the transfer roller. The movable member is moved to a detection position of the detector by rotation of the transfer roller.

Abstract: A secondary transfer portion includes a transfer roller, a fixing member, a movable member, and a detector. The transfer roller is configured to rotate about an axis thereof when the secondary transfer portion is attached to an apparatus body. The fixing member is fixed to the axial end portion of the transfer roller. The movable member is caught on the fixing member. The detector is configured to indicate different detection states depending on a position of the movable member. The fixing member and the movable member are connected to each other through a guide mechanism (a guide groove and a guide protrusion) that is configured to move the movable member in an axial direction of the transfer roller. The movable member is moved to a detection position of the detector by rotation of the transfer roller.

Abstract: A roller device includes a roller main body, a shaft member, flanges, a position restricting member, a plate-shaped member, a biasing member, and a securing member. The shaft member is inserted into the roller main body and the flanges in contact with both ends of the roller main body. The position restricting member is secured to the shaft member at an end portion side of the shaft member with respect to the flange. The position restricting member restricts an axial position of the flange. Movement of the plate-shaped member toward the end portion side in an axial direction is restricted by the position restricting member. The biasing member biases the flange toward a center side in the axial direction. The securing member is disposed at the end portion side of the shaft member with respect to the plate-shaped member. The securing member engages the position restricting member.

Abstract: An intermediate transfer unit includes a shaft, a joint member, an apparatus frame and a supporting member. The joint member includes a first concave portion in which a first end portion in a longitudinal direction of the shaft is fittable at a plurality of angles around a first axis of the shaft, and a first peripheral portion having a second axis that is parallel to but does not share the same straight line with the first axis. The apparatus frame has a through hole. The supporting member has a second concave portion which the first peripheral portion is attachable to and removable from at a plurality of angles around the second axis, and is insertable into and removable from the through hole in the longitudinal direction.

Abstract: A roller device includes a roller main body, a shaft member, flanges, a position restricting member, a plate-shaped member, a biasing member, and a securing member. The shaft member is inserted into the roller main body and the flanges in contact with both ends of the roller main body. The position restricting member is secured to the shaft member at an end portion side of the shaft member with respect to the flange. The position restricting member restricts an axial position of the flange. Movement of the plate-shaped member toward the end portion side in an axial direction is restricted by the position restricting member. The biasing member biases the flange toward a center side in the axial direction. The securing member is disposed at the end portion side of the shaft member with respect to the plate-shaped member. The securing member engages the position restricting member.