| 摘要 |
FIELD: radio engineering, communication.SUBSTANCE: noise is generated and door actuators are damaged if the delay time of an electromagnet operating on disengagement is exceeded. The device consists of an additional switch connected in series or in parallel to exit buttons of a doorphone. The additional switch is mounted on the door frame. The additional switch is triggered by the entrance door at the end of the motion mechanically or by a magnet and triggers a new count of the delay time of the electromagnet. The door quietly sits at its place. The electromagnet is then triggered. Use of this device prevents slamming of the entrance door when the delay time of an electromagnet operating on disengagement is exceeded. The door closing time can increase during exit of several people, when carrying in carriages, loads, children, at low ambient temperature etc. The service life of the door actuator is prolonged. Electric power is saved.EFFECT: low maintenance cost.2 dwg |
