| 摘要 |
An arrangement for operating a door includes a power cylinder 36 connectible to a door (not shown) for controlling its movements. A control means (not shown) controls the driving motor 7 operating a pressure pump 5 and thereby to actuate the power cylinder 36 of a door closer unit 1 of the kind having a main cylinder housing a first piston member 12 moving in accordance with the movements of the door and thereby pumping pressure medium from a first chamber I to another chamber II through a first flow duct 16 interconnecting the chambers I and II. The door closer unit 1 is provided with a spring member 11 urging the door to closed position and with a throttling means 18 for damping the closing movement of the door. The chambers I and II, the first flow duct 16 and the pump 5 are parts of a closed pressure medium system, in which the chamber II is connected to the suction side of the pump and the chamber I to the pressure side of the pump. Valve means 17 prevents direct pressure medium flow between the two chambers and for leading the pressure medium to pass through the pump 5 so as to be pumped from one of the chambers to the other in a direction giving the door an opening movement. The control means for the motor 7 is able to disconnect the door closer unit 1 from the influence of the pump 5 and leave it free to work as a normal door closer. <IMAGE> |
