Abstract: A reversible percussion device, having a casing 1 in which is installed a movable striker and a system for distributing fluid under pressure for causing the striker 4 to move for both forward and rearward movement functions of the device. The system comprises a control member 9 for controlling the distribution of fluid under pressure for both functions, which is movably coupled to the striker 4 and has a mechanism for locking it with respect to the casing 1 in two control positions, corresponding to the two functions of the device. According to the invention, the mechanism for locking the control member 9 in the position enabling the forward movement functions of the device comprises a body 11 movable relative to the control member 9.

Abstract: A specific feature of the apparatus according to the invention which incorates a percussion unit to a tail piece whereof there is attached a rope connecting to a means of extracting is that fitted into said tail piece coaxially therewith and with a clearance is a ring, the clearance between said ring and said tail piece containing a resilient member with passages reeved wherethrough are the ends of the rope and the inside surface of said tail piece being provided with stops in the body whereof there are also passages for reeving the ends of the rope.

Abstract: The percussive action pneumatic device for drilling holes in a soil by cocting same has a cylinder-shaped housing with a conically pointed head portion. This pointed head portion of the housing is engaged in the internal surface of the tail portion of a hollow tip with a pointed end. A transverse partition is provided internally of the hollow tip, in the tail portion thereof, the head portion of the housing is detachably connectable with the transverse partition.

Abstract: The device comprises a hollow cylindrical body, pointed front at its end which device accommodates a striker forming the front working chamber in said body, and has a cylindrical space at its rear end. Said space receives an air-distributing and reversing mechanism, thus forming the rear working chamber. The air-distributing and reversing mechanism has a bushing which is fixed relative to the body, and an axially movable bushing, both bushings being arranged coaxially, spring-loaded in the axial direction relative to each other, and forming a chamber located in the front part of said mechanism, with the chamber communicating with a source of compressed air and intended to move the movable bushing during reversal of the device.