Firing signal for practice mine - has first gas charge loosening earth above mine and second delayed charge providing smoke signal

摘要

The practice mine is buried in the ground and has a compartment fitted with a grille (37, 38). The compartment is in two parts, the upper containing a gas generating charge (45). Contact pressure fires a detonator (54) and this charge, the high gas pressure forcing up a plunger (46) to compress a rubber gasket (53). The gas escapes through the grille to loosen the earth above. A second fuse (64) is ignited and a charge (60) in the lower compartment generates gas which escapes through the centre (70, 72) of the plunger in the form of a jet. Simultaneously, smoke powder (63) is ignited to provide a visible signal.