초록 ▼

A primer assembly is provided for use in vertical boreholes wherein the primer charge is initiated by means of electric blasting caps, the electric caps, in turn, being initiated electromagnetically. A covered, cup-shaped primer assembly contains a toroid transformer element and connected electric b

A primer assembly is provided for use in vertical boreholes wherein the primer charge is initiated by means of electric blasting caps, the electric caps, in turn, being initiated electromagnetically. A covered, cup-shaped primer assembly contains a toroid transformer element and connected electric blasting cap in detonating relationship with a primer explosive charge. The assembly is arranged to receive therethrough a looped wire conductor which conductor passes freely through the toroid transformer. When an energy source is coupled to the looped conductor, a magnetic flux is induced in the toroid transformer which sets off the cap and primer charge. The assembly may be passed freely or slid along the looped conductor to any location in the borehole. The assembly permits the use of electric time-delay, deck-charge blasting without the usual hazards associated with normal electric cap blasting.

대표청구항 ▼

A primer assembly for initiating explosives in a vertical borehole by means of electric blasting caps which are initiated electromagnetically comprising: (a) a priming charge of high explosives, (b) a cylindrical, open-top, cup-like container body having means thereon to support a toroid transformer

A primer assembly for initiating explosives in a vertical borehole by means of electric blasting caps which are initiated electromagnetically comprising: (a) a priming charge of high explosives, (b) a cylindrical, open-top, cup-like container body having means thereon to support a toroid transformer element and attached lead wires and electric blasting cap, said blasting cap being positioned in detonating relationship with the said priming charge of high explosives, and (c) an interlocking cover for said cylindrical cup-like container, the said cylindrical cup-like container and interlocking cover having apertures therein at a location in alignment with the hollow center of the said toroid transformer element, said apertures being at least of a size to permit free slidable passage therethrough of an insulated electric wire having a diameter of at least 1.15 mm.