| 摘要 |
PURPOSE:To prevent a pressure plate from floating unnecessarily and make possible good free opening and closing by placing the engagement position of an arm and a pressure-contact member within the region where the straight lines connecting the center of gravity of the pressure-contact member and supports intersect. CONSTITUTION:An original pressure plate 1 is held supported to supports 3 turnably around shafts 2. The supports 3 are secured to stanchions 4, which stanchions 4 are supported vertically slidably by being guided with the guide pipes provided to the copying machine body side. An engaging member 5 which receives the opening and closing action force by an arm 7 is secured to the side face of the pressure plate 1, and the position where this engaging member 5 is secured is placed within the region S sandwiched by the two straight lines (a), (b) by extending the straight lines (a), (b) connecting the stanchions 4 and the center of gravity M of the pressure plate 1. Thereby, the pressure plate may be automatically opened and closed well without impairing its function. |
