Image reading device and image forming apparatus therewith

An image reading device comprising:

• a contact glass which is fixed to a top face of a scanner frame and which is divided into a manual placement document glass and an automatic read glass;
• a document transport device which is openable/closable with respect to the contact glass in an up-down direction and which transports a document over a top face of the automatic read glass;
• a first reading module which is arranged under the contact glass so as to be reciprocatable in a sub-scanning direction, the first reading module being capable of reading an image on an obverse side of a document placed on the manual placement document glass while moving in the sub-scanning direction and capable of reading an image on an obverse side of a document transported over the top face of the automatic read glass while remaining at rest at a reading position facing the automatic read glass;
• a second reading module which is arranged inside the document transport device, the second reading module being capable of reading an image on a reverse side of the document transported over the top face of the automatic read glass;
• an opposite roller which is arranged opposite an image reading surface of the second reading module and which transports the document while keeping the document in close contact with the image reading surface;
• and
• roller holders which rotatably support opposite end parts of a rotary shaft of the opposite roller,
• wherein
• on faces of the roller holders facing the second reading module, a pair of patterns for detection is provided that is formed, inside a readable region of the second reading module, but outside a reading region of a document image, on the opposite end parts of the rotary shaft of the opposite roller in an axial direction thereof perpendicular to a document transport direction,
• the patterns for detection are each formed so as to have an intersection in a central part thereof with respect to the document transport direction, be increasingly wide toward a first end side in the axial direction upstream from the intersection with respect to the document transport direction, and be increasingly wide toward a second end side which is opposite from the first end side downward from the intersection with respect to the document transport direction,
• the second reading module reads the patterns for detection to detect an inclination of the opposite roller,
• on the faces of the roller holders facing the second reading module, a pair of positioning protrusions is provided that is formed on a straight line passing through a center of an axis of the opposite roller and that regulates a gap between the opposite roller and the image reading surface of the second reading module by staying in contact with the image reading surface, and
• the positioning protrusions protrude toward the second reading module beyond the patterns for detection.

An image reading device comprising:

• a contact glass which is fixed to a top face of a scanner frame and which is divided into a manual placement document glass and an automatic read glass;
• a document transport device which is openable/closable with respect to the contact glass in an up-down direction and which transports a document over a top face of the automatic read glass;
• a first reading module which is arranged under the contact glass so as to be reciprocatable in a sub-scanning direction, the first reading module being capable of reading an image on an obverse side of a document placed on the manual placement document glass while moving in the sub-scanning direction and capable of reading an image on an obverse side of a document transported over the top face of the automatic read glass while remaining at rest at a reading position facing the automatic read glass;
• a second reading module which is arranged inside the document transport device, the second reading module being capable of reading an image on a reverse side of the document transported over the top face of the automatic read glass;
• an opposite roller which is arranged opposite an image reading surface of the second reading module and which transports the document while keeping the document in close contact with the image reading surface;
• and
• roller holders which rotatably support opposite end parts of a rotary shaft of the opposite roller,
• wherein
• on faces of the roller holders facing the second reading module, a pair of patterns for detection is provided that is formed, inside a readable region of the second reading module, but outside a reading region of a document image, on the opposite end parts of the rotary shaft of the opposite roller in an axial direction thereof perpendicular to a document transport direction,
• the patterns for detection are each formed so as to have an intersection in a central part thereof with respect to the document transport direction, be increasingly wide toward a first end side in the axial direction upstream from the intersection with respect to the document transport direction, and be increasingly wide toward a second end side which is opposite from the first end side downward from the intersection with respect to the document transport direction,
• the second reading module reads the patterns for detection to detect an inclination of the opposite roller, and
• the image reading device can perform an inclination adjustment mode comprising:
• reading the patterns for detection;
• displaying an output value of the second reading module as obtained when the patterns for detection are read as a measured output value, and displaying an output value of the second reading module as obtained when the opposite roller is not inclined as a reference output value;
• and
• moving the roller holders based on an inclination direction and an inclination amount of the opposite roller that are calculated based on the measured output value and the reference output value that are displayed.