Mine detonator with electric ignition

Claim 1

In an electrically ignited detonator particularly for use with tank mines, a piezoelectric crystal transmitter having opposite output terminals, an ignition circuit interconnecting said output terminals, a primer capsule in said circuit, a condenser in said circuit connected in series with said primer capsule, normally open switch means in said circuit connected in series with said primer capsule between said condenser and said primer capsule, said circuit being closed when the sum of a plurality of voltage impulses generated by an equal number of mechanical impacts on said piezoelectric transmitter reaches a predetermined total value, rectifier means in said circuit between said piezoelectric transmitter and said condenser, and high-ohmic resistor means in said circuit connected in parallel with said condenser so that upon each of said mechanical impacts on said piezo-electric transmitter said condenser is successively charged by the resulting voltage impulses from said piezoelectric transmitter and is partially discharged through said high-ohmic resistor means until the sum of the residual charges on said condenser reaches said predetermined total value thereby to close said switch means and cause said primer capsule to ignite and detonate the mine.