| 摘要 |
PURPOSE:To make automatic closing of a door surely feasible by constructing the title device in a structure wherein a cam of a main shaft and a roller separate from each other while a cam of a counter shaft and a roller contact each other as the angle of opening of the door becomes larger. CONSTITUTION:As a door is opened counterclockwise at an angle of about 5 degrees, a main shaft 2 turns counterclockwise and a counter shaft 5 turns clockwise at an angle of about 2.9 degrees. A conversion curve 3c on the upper side of a cam 3 of the main shaft 2 pushes a roller C1 leftward, and a sliding plate 10 is moved leftward thereby, making a piston 14 move leftward. As the door is opened clockwise at an angle of about 190 degrees, a cam 6 of the counter shaft 5 turns at an angle of about 111.7 degrees, making a loose curve 6a of the cam 6 engaged with a roller C4, and the piston 14 is moved leftward thereby. When the door is set free, the counter shaft 5 turns in the opposite direction being urged by restoring force of a returning spring 13 and the main shaft 2 turns in the direction opposite to the turning of the counter shaft 5 and a force is given thereby to the door in the closing direction. |
