| 摘要 |
<p>PURPOSE: A door closer and a device for opening and closing an entrance door using the same are provided to maintain the opened state of an entrance door when loads are placed on the inlet of the entrance door. CONSTITUTION: A door closer is composed as follows. A box-shaped case(11) is installed in a door frame. A rotary housing is hinged on one side of the case. A lower plate and an upper plate are installed in the rotary housing and form a shaft hole and a motor mounting unit, respectively. A hinge pin, protruded from one end of the rotary housing, is hinged on the case. A double gear, composed of upper and lower gears, is rotatably installed in a gap between the upper and lower plates. A motor with a drive screw is installed in the motor mounting unit. The drive screw is meshed with the lower gear.</p> |
