| 摘要 |
<p>An alarm call point comprises a housing 4 and having a pivotably mounted window 6 for operation of the device. The window 6 carries a conductive track l0 along one edge which is in electrical contact with a pair of resilient contact members l2 when the call point is in the unoperated condition. When the call point is activated the contact between the track l0 and contact members l2 is broken, activating the alarm. The contact members l2 are shaped to provide a tactile feel to the operation of the device and may allow a limited degree of movement to the window in the operated condition to provide a continued indication of the the device having been operated. The call point enables a microswitch usually incorporated in such devices to be obviated and enables the device to be tested by actual operation rather than by a simulation technique. <IMAGE></p> |
