| 摘要 |
<p>Electric energy sent from a blasting machine is received via a pair of input terminals and charged to a charging circuit to drive an electronic timer. The electronic timer performs, by issuing an enable signal a preset time later and detecting the charging voltage level of the charging circuit, a first operation leading to detonation and a second operation for setting detonation conditions. The first operation issues a trigger signal a second reference time later set by the second operation and discharges the accumulated electric energy to cause detonation. Since a detonation start signal need not be received and, therefore, there is little possibility of detonation being erroneously started, a blasting operation will not fail to ensure a safe and erro-free blasting operation.</p> |
