Cover opening and closing mechanism and image forming apparatus

A cover opening and closing mechanism, comprising:

• a first cover member that is a part of a housing and swings between an open position and a close position about a first rotation point;
• having a first sheet placing surface, a direction from the open position to the close position being defined as a close direction, and
• a second cover member that swings about a second rotation point in conjunction with a movement of the first cover member, having a second sheet placing surface, wherein
• the first cover member has a first engagement part at a distal end of the first sheet placing surface,
• the second cover member has a second engagement part, which engages with the first engagement part when the first cover member is positioned at the close position, at a distal end of the second sheet placing surface so that the first sheet placing surface is flush with the second sheet placing surface,
• during a process in which the first cover member swings in the close direction, a first contact part of the first cover member, which is other than the first sheet placing surface, contacts to a second contact part of the second cover member, which is other than the second sheet placing surface, before the first engagement part contacts to the second engagement part,
• the first engagement part is provided with a guide rib that is at a distal end thereof, extends toward the downstream and the first rotation point,
• seen from a axial direction of the first rotation point, a moving path of a front end of the guide rib is defined as a third engagement path, a moving path of the second engagement part is defined as a second engagement path,
• the third engagement path and the second engagement path are arranged to intersect at a first cross point, and
• the first cross point is located at a downstream in the close direction from a second cross point where the first contact part contacts to the second contact part.

A cover opening and closing mechanism for a printer, comprising:

• a first cover member that is a part of a housing and swings between an open position and a close position about a first rotation point, a direction from the open position to the close position being defined as a close direction, the first cover member having,
• in an axial direction of the first rotation point, a first sheet placing surface arranged at a middle and a first contact part arranged at one of side ends of the first sheet placing surface, and
• the first sheet placing surface having a first engagement part at a distal end of the first sheet placing surface,
• a second cover member that swings between an open position and a close position about a second rotation point, a direction from the open position to the close position being defined as a close direction, the second cover member having,
• in the axial direction, a second sheet placing surface arranged at a middle and a second contact part arranged at one of side ends of the second sheet placing surface, and
• the second sheet placing surface having a second engagement part, which engages with the first engagement part when the first cover member is positioned at the close position, at a distal end of the second sheet placing surface so that the first sheet placing surface is flush with the second sheet placing surface for stacking sheets, and
• seen from the axial direction,
• moving paths of the first engagement part and the first contact part are respectively defined as a first engagement path and a first contact path, both of which swinging about the first rotation point,
• moving paths of the second engagement part and the second contact part are respectively defined as a second engagement path and a second contact path, both of which swinging about the second rotation supporting point,
• the first engagement path and the second engagement path intersect at a first cross point, and
• the first contact path and the second contact path intersect at a second cross point, wherein
• in the close direction, the first cross point is at a downstream from the second cross point so that the first contact part of the first cover member contacts to the second contact part of the second cover member before the first engagement part contacts to the second engagement part.