| 摘要 |
1450521 Land mines FORENADE FABRIKSVERKEN 25 March 1975 [29 March 1974] 12484/75 Heading F3A A device for detonating a land mine if an attempt is made to remove the land mine from the ground, comprises: a magnetic field sensing device for detonating the mine, e.g. a coil 1, and an annular tube 2 containing a magnetized ball 3 which, when the mine is disturbed, rolls around the tube and induces a current in the coil. The ball is prevented from rolling, when subjected to small vibrations, by being wedged between oppositely inclined internal surfaces of the tube or by being seated on a surface formed with a plurality of radial grooves or ridges. In the latter instance, rolling of the ball may be facilitated by the provision of an inclined planar surface on to which the ball moves when the mine is tilted. |
