| 摘要 |
PURPOSE:To shorten a span of time of up to being fully closed since door- bitingness has occurred by lowering the extent of pressure in a fluid out of a driving pressure source so as to reduce the driving force of a door after detecting such a state only at a time when a man or article is pinched in the door, and when nothing is caught in the door, feeding a door driving part with a pressure fluid at usual high pressure. CONSTITUTION:When door-bitingness is detected, a selector signal is outputted out of a decompressive command output part 26. This selector signal is given to a selector solenoid valve 4, and a pressure air supply source 10 is connected to a driving cylinder 12 via a pipeline 30 and a pressure reducing value 3. Air pressure to be fed to this driving cylinder 12 is decompressed, whereby force acting on a door is reduced to some extnet. After the elapse of the specified time so far set to a timer 25, output of the selector signal is stopped and the solenoid valve 4 is selected to its origonal state, thereby turning to a supply state of high pressure air. |
