| 摘要 |
A nightlatch is provided with an internal spring clip located inside the key cylinder with the spring clip and the key cylinder housing being electrically isolated and forming opposing terminals of a low voltage solenoid 4, such that when a key is inserted it completes the circuit and activates the solenoid causing a bolt 3 to project outwards and engages with the striker plate 5. The bolt engaging with the door frame prevents the door closing until the key is withdrawn which breaks the circuit allowing the bolt to return to neutral (retracted position). |
