| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect crushing powder or explosive accurately regardless of the conductivity or permittivity of an object to be blasted, e.g. rock, bed rock or concrete, even if an electromagnetic wave reflecting material, e.g. iron rod, is mixed. SOLUTION: A detecting element 10 comprising an antenna coil 11 and a capacitor 13 connected across the antenna coil 11 to form a resonance circuit 12 along with the antenna coil 11 is set at a specified place along with a crushing powder or explosive 15. After the crushing powder or explosive 15 is combusted, a radio wave having resonance frequency of the resonance circuit 12 is transmitted to the specified place and the detecting element 10 is detected based on the presence of reflected radio wave from the antenna coil 11 thus detecting misfired crushing powder or detonator 15.</p> |
