Document conveying device and image forming apparatus including the same

A document conveying device, comprising:

• a document stacking tray on which a plurality of document sheets are stacked:
• a feeding unit that has a unit frame body that is swingably supported, at an end portion thereof on a downstream side in a document conveying direction, on a first swinging fulcrum on a main body side of the document conveying device, and a pickup roller that is rotatablv supported on a swingable end side of the unit frame body, and is disposed selectively at a paper feeding position where the pickup roller is brought in press-contact with an upper surface of a stack of document sheets stacked on the document stacking tray or at a retracted position where the upper surface of the stack of document sheets and the pickup roller are separated by a predetermined distance from each other;
• a stopper that is swingably supported on a second swinging fulcrum provided on the swingable end side of the unit frame body, and has a document restriction portion that extends from the second swinging fulcrum to become opposed to tip ends of the stack of document sheets stacked on the document stacking tray and an engagement piece that is provided to protrude from the second swinging fulcrum in an opposite direction to the document restriction portion:
• and
• a restriction surface that is provided on the main body side of the document conveying device, and extends downward from a position coinciding with a first trajectory, along which the engagement piece moves as the stopper is swung about the second swinging fulcrum, toward an inner side of the first trajectory, while extending downward from a position coinciding with a second trajectory, along which the engagement piece moves as the feeding unit is swung about the first swinging fulcrum, toward an inner side of the second trajectory,
• wherein when the feeding unit is at the retracted position, the engagement piece is engaged with the restriction surface, so that the document restriction portion is brought into a position opposed to the tip ends of the stack of document sheets, and thus an opposed fixed state is brought about where swinging of the stopper is restricted, and when the feeding unit is at the paper feeding a position, the engagement between the engagement piece and the restriction surface is released, and thus a fixing released state is brought about where the swinging of the stopper is allowed, and
• the second swinging fulcrum is made up of a stopper spindle that is formed on the unit frame body and a bearing hole that is formed in the stopper and through which the stopper spindle slidably penetrates, and
• a maximum value d1 of a gap between an outer peripheral surface of the stopper spindle and an inner peripheral surface of the bearing hole is not less than a maximum value d2 of a length by which the restriction surface protrudes to the inner side of the second trajectory.