| 摘要 |
A security system for detecting the fracture of a pane of glass is disclosed in which a fracture detector means 14 is provided in the form of a resilient sealing member 16, 216, 316 with which the glass 20, 220, 320 is normally in contact. The resilient sealing member 16, 216, 316 has at least one sensor 18, 19; 118, 119; 218, 219; 318, 319 formed as part of it, the state of which is changed when the glass 20, 220, 320 is fractured. A control means 11 upon sensing the change of state of the or each sensor 18, 19; 118, 119; 218, 219; 318, 319 is arranged to energise a warning device 12. <IMAGE> |
