Back to results
US 8,577,253 B2Granted
Image forming apparatus
AssigneeBrother Kogyo Kabushiki Kaisha
InventorsHirotaka Mori, Masato Makino
Life of this patent
Estimating the term…
Abstract
An image forming apparatus may include a removable/attachable belt unit. In operation, the belt unit may be secured to a main body of the image forming apparatus using a lock mechanism to prevent extraneous or unexpected shifts and/or other movements. The lock mechanism may be located closer to a rotation pivot than to a midpoint between the rotation pivot and a rotation axis of a driven roller. This positioning of the lock mechanism may allow easier attachment and removal of the belt unit. Additionally, the lock mechanism may include an urging member configured to sandwich a protruding member of the belt unit against a contact surface in a front-rear direction. This reduces the potential for elastic or creep deformation of the belt unit.
Claims20
An image forming apparatus comprising:
- a main body having an opening;
- an image forming unit disposed in the main body and having an image carrier, the image forming unit being configured to form an image on the image carrier;
- a belt unit detachably attached in an operation position where the belt unit faces the image forming unit in the main body, the belt unit including:
- a first roller disposed at a first end of the belt unit,
- a second roller disposed at a second end of the belt unit,
- an endless belt extending between the first roller and the second roller, and
- a pivot shaft portion disposed at the first end;
- a fixing mechanism configured to fix the belt unit in the operation position;
- and
- an engaging portion configured to engage the fixing mechanism and to receive an urging force from the fixing mechanism, such that the belt unit is fixed in the operation position, wherein the engaging portion is disposed between the pivot shaft portion and a midpoint between a rotation axis of the second roller and the pivot shaft portion,
- wherein the main body further includes a pivot support portion configured to support the pivot shaft portion such that the belt unit pivots around a pivot axis disposed along the pivot shaft portion, and
- wherein the fixing mechanism is configured to fix the belt unit in the operation position by applying the urging force to the engaging portion when the belt unit pivots around the pivot axis.
9 more elements
An image forming apparatus comprising:
- a main body having an opening;
- an image forming unit disposed in the main body and having an image carrier, the image forming unit being configured to form an image on the image carrier;
- a belt unit detachably attached in an operation position where the belt unit faces the image forming unit in the main body, the belt unit including:
- a first roller disposed at a first end of the belt unit,
- a second roller disposed at a second end of the belt unit,
- an endless belt extending between the first roller and the second roller, and
- a pivot shaft portion disposed at the first end;
- a fixing mechanism configured to fix the belt unit in the operation position;
- and
- an engaging portion configured to engage the fixing mechanism and to receive an urging force from the fixing mechanism, such that the belt unit is fixed in the operation position, wherein the engaging portion is disposed between a rotation axis of the second roller and the pivot shaft portion,
- wherein the main body further includes a pivot support portion configured to support the pivot shaft portion such that the belt unit pivots around a pivot axis disposed along the pivot shaft portion,
- wherein the fixing mechanism is configured to fix the belt unit in the operation position by applying the urging force to the engaging portion when the belt unit pivots around the pivot axis,
- wherein the first roller of the belt unit is a drive roller and the second roller of the belt unit is a driven roller, and
- wherein the belt unit further includes:
- a belt unit body;
- and
- an urging member configured to apply a tension to the endless belt by urging the driven roller in a direction away from the drive roller, wherein the endless belt is wound around the drive roller and the driven roller.
14 more elements
An image forming apparatus comprising:
- a main body having an opening;
- an image forming unit disposed in the main body and configured to form an image on a recording medium;
- a belt unit detachably attached in an operation position where the belt unit faces the image forming unit in the main body, the belt unit including, a first roller, a second roller, and an endless belt wound around the first roller and the second roller and being configured to rotatably hold the endless belt to feed the recording medium;
- and
- a lock mechanism disposed in the main body, the lock mechanism being configured to fix the belt unit in the operation position by applying an urging force to the belt unit,
- wherein the belt unit is attached in the operation position along an attachment direction in which the belt unit is inserted from outside of the main body through the opening into the main body and toward the operation position,
- wherein the belt unit includes a pivot shaft portion that is disposed on a front side relative to the attachment direction and an engaging protruding portion that protrudes outward in a width-wise direction of the endless belt,
- wherein the engaging protruding portion is disposed between a rotation axis of the second roller disposed on a rear side relative to the attachment direction and the pivot shaft portion,
- wherein the main body includes a pivot support portion that is disposed on the front side relative to the attachment direction and is configured to engage the pivot shaft portion and support the belt unit pivotally around a pivot axis, wherein the pivot axis is horizontal and perpendicular to the attachment direction, and
- wherein the lock mechanism is configured to fix the belt unit in the operation position by applying the urging force to the engaging protruding portion when the belt unit pivots around the pivot axis.
7 more elements
Dependencies are inferred from the claim text.