Up-down vibratory drilling and jarring tool

摘要: A drilling and vibratory jarring device is provided. The has an inner mandrel shiftable upward or downward in outer housing from intermediate position the housing. When within mating splines, one set of splines attached to mandrel, other housing, engage rotatably lock together. shifted said disengage saw-tooth surfaces upper pair jars creating longitudinal forces down-hole when rotated with respect lower may thus be a drill string during normal, rotary operations by shifting used create earth bore.