ELECTRIC PULSE DRILLING BIT Russian patent published in 2013 - IPC E21C37/18 E21B10/00 

FIELD: mining.

SUBSTANCE: electric pulse drilling bit comprises cylindrical, coaxially arranged and separated with a high-voltage insulator outer and inner crowns made with side washing windows. The bottomhole part of the outer crown is equipped with evenly arranged radial ribs-electrodes, between every pair of which there is one outer radial rib-electrode of the inner crown installed in an equidistant manner. The value of the gap between the outer and inner crowns, in which a high-voltage bushing is installed, is more than electrode-to-electrode distance in the bottomhole part of the electric pulse drilling bit. As an option, width and height or diametre of upper washing windows of the inner crown are more than the maximum electrode-to-electrode distance. As an option, upper washing windows of the inner crown are arranged at height from its bottomhole end surface that is higher than height of largest core pieces.

EFFECT: increased service life of a bit and a high-voltage bushing included into its composition.

3 cl, 6 dwg