A percussion device is an inversion of the marketing authorisation holder

摘要

The invention relates to the public works machines. / p & & p & the device forming the subject of the invention is characterizes in that the projections 14 of the bushing 10 are placed in the grooves 20 of the control element 9, the bearing 10 itself - even being encased in a frame 11 provided with openings and willing between the body 1 and the control element 9 with the possibility of displacement along the axis of the device. / p & & p & the device is intended mainly to the embodiment, in the ground, of the well to the laying of lines of communication without digging of underground trenches.