Patents Assigned to Euro-Matsushita Electric Works AG.
  • Patent number: 5571985
    Abstract: A sequential blasting system for use in particular in mining comprises a plurality of detonator stages S1, S2, . . . , each of which contains a series circuit consisting of a thyristor T and a detonator means ZE, said series circuit being interposed between two supply leads A, O; B, 0. The signal voltage for the thyristor T in each stage is derived solely from the switching state of the thyristor T of the preceding stage. This causes activation to be transferred from stage to stage independently of the detonator means ZE, in particular irrespectively of whether or not a detonator has been attached and whether or not this detonator becomes highly resistive or not as it should upon being activated. This eliminates the errors that have occurred in known circuits. Upon firing the blasting system, such errors can cause the detonation to occur not only at the first detonator stage, but simultaneously at a location where a detonator is missing as well.
    Type: Grant
    Filed: April 25, 1995
    Date of Patent: November 5, 1996
    Assignee: Euro-Matsushita Electric Works AG.
    Inventors: Heinz Ritter, Wolf Steinbichler