| 摘要 |
978,444. Burglar alarms. J. KOWANDA. June 20, 1962, No. 23789/62. Heading G4N. The vibration of a vehicle causes operation of a burglar alarm therefor by vibrating a spring 6 to make and break a switch 2, 3 in the alarm circuit. The spring carries an insulated weight 8 at its free end and at its other end is sheathed in a flattened sleeve 9 of soft metal, e.g. copper, by which it is screwed to a housing 1. The contact 3 is formed by the end of an adjustable bolt 14 locked in position by a nut 17. |
