| 摘要 |
The invention provides a device for holding open a sliding door 1 such as a fire-protection door. An electromagnet 14 is mounted on a common carrier element 24 together with a latching mechanism 15, the latching mechanism comprising a twin-armed lever mounted on a pivot pin 18, one lever arm 16 is provided with an armature plate 21 positioned adjacent to the electromagnet 14, whilst the other lever arm 17 is provided with a latch 30 for engaging with a detent 28 mounted along the upper edge of the door. When the electromagnet is energised, the door can be opened and will be held in its open position due to co-operation between the latch 30 and the detent 28, but when the electromagnet is de-energised, the twin-armed lever can pivot about the pin 18 and allows the door to close. The electromagnet 14 may be coupled with a smoke detector or heat-sensitive switch and is de- energised in the event of smoke or heat generation. <IMAGE> |
