PURPOSE: To obtain a trigger device which operates securely even if it is separated from a work, by constituting it so that two pieces each of metallic plates and insulating plates are superimposed alternately in a shape of a sandwich and a small hole is pierced, and a high voltage is applied between said two pieces of metallic plates.
CONSTITUTION: The trigger device 5 is positioned without contact to a work 9 by providing a small through-hole 24 on metallic plates 23, 26 and insulating plates 21, 22 superposed alternately, and inserting an induction coil 8 between the metallic plates 23, 26. When a switch 12 is closed and the high voltage of the coil 8 is applied between the metallic plates 23, 26, a large quantity of secondary electrons are generated in a rod-shaped electrode 4 by a discharge ion generated on the end face 25 of the insulating plate 22. When a main electric discharge is induced by said secondary electron, a charge charged to a capacitor, too gives a shock to the work 9 through the small hole 24 in a moment. In this way, a trigger device which operates surely even if it does not contact to a work is obtained.
ASANUMA YOSHIMITSU