Abstract: A percussion apparatus driven by a pressurized incompressible fluid includes a body with two coaxial bores for slidably mounting of a tool, and separately slidably mounting a striking piston having a stepped configuration. A control device varies a stroke of the striking piston between a long and a short stroke, and is connected to the directional flow valve and to a bottom chamber of the piston cylinder. The control device includes a cylinder in which a spool is mounted. A first face of the spool is situated in a first chamber permanently subjected to a determined pressure, and a second face of the spool is situated in a second chamber connected to the braking chamber for controlling the varying of the stroke of the striking piston.

Abstract: According to the invention, the body of the apparatus includes a flow rate adjustment device including a calibrated opening provided on a high-pressure fluid supply circuit, a bore formed in the body and in which is mounted a slider having a first face located in a first chamber connected to a high-pressure fluid supply circuit upstream from the calibrated opening and a second face located in a second chamber connected to the high-pressure fluid supply circuit downstream from the calibrated opening, the bore receiving the slide including an annular groove connected to a low pressure feedback circuit. The slider is adapted for connecting the annular groove to the first chamber when the pressure difference on either side of the calibrated opening increases beyond a predetermined value in order to divert a portion of the fluid flow supplied by the high-pressure fluid supply circuit to the feedback circuit.

Abstract: The equipment comprises a body (2) inside which there are a bore in which a tool (3) is slideably mounted and a stepped bore forming a cylinder for a stepped piston (1) which together with this bore delimits a top chamber (5) and a bottom chamber (4) which chambers are sequentially supplied with incompressible fluid under high pressure under the action of a directional control valve (6), a control device varying the stroke of the striking piston between a long stroke and a short stroke and vice versa. The control device comprises a cylinder into which there opens at least one port (14) which also opens into the cylinder of the striking piston (1), and a port (13) connected to the directional control valve and in which a spool (12) is mounted, a first face of which spool lies in a first chamber (17) constantly subjected to a determined pressure and the second face of which spool lies in a second chamber (21) connected to a braking chamber (10).

Abstract: The invention relates to a hydraulic rotary percussive device of the drill type, intended for drilling boreholes, comprising: a striking mechanism equipped with a piston which is able to move translationally along a striking axis and is intended to strike a tool; a hydraulic motor which rotates the tool about an axis of rotation, the axis of rotation of the motor being substantially coincident with the striking axis of the piston, wherein it comprises a support-forming casing, the striking mechanism being hydraulic and having a longitudinal body rotatably mounted in the casing about the axis of the body, the body being rotated directly by the motor and coupled to the tool.

Abstract: The invention relates to a bucket-, claw-, scraper-blade- or compacting-type attachment (1) which is intended to be fitted at one end (18) of a rock breaker (15) comprising a tool (17). The inventive attachment comprises: (i) means (7, 8, 9, 12) enabling the correct positioning thereof in relation to the rock breaker and the tool; and (ii) means (13, 14, 20) for fixing same temporarily and removably to the end of the rock breaker, without dismantling the tool (17).

Abstract: A percussive apparatus comprises a body inside of which a striking piston is mounted in a cylinder bore. Two axially offset pieces are mounted inside the cylinder bore of the body while being concentric to the piston, and a deformable washer is placed between said pieces. One of the pieces is stationary with regard to the other piece that, however, is mounted in a manner that enables it to slide inside the cylinder bore and to be displaced in the direction of the stationary piece while being subjected to the action of the supply pressure of the hydraulic fluid that acts upon the surface of the moving piece facing away from the side opposite the stationary piece. The displacement of the moving piece causes the elastic washer to deform in order to create a passage with a variable cross-section on the return circuit of the hydraulic fluid to the reservoir or on a circuit that diverts, to the return circuit, a portion of the delivery flow of the apparatus whereby regulating the input pressure.

Abstract: The ramming device comprises a ramming element to be assigned to the end of a rock breaker. The inventive device receives the shocks generated by the rock breaker and transmits them to fragments to be compacted. The ramming device also has a frame comprising: positioning structure for positioning relative to the rock-breaker so that the axis of the frame is coincident with the axis of the rock breaker; joining structure that enable the temporary and removable fixing of the frame to the end of the rock breaker; axially translational guiding structure for guiding the ramming element relative to the frame; structure for blocking the rotation of the ramming element about the axis of the frame, and; structure for limiting the amplitude of this translation.

Abstract: The inventive device includes a casing, inside of which the body is accommodated that has the hydraulic striking mechanism, inside of which a bush is mounted for guiding a tool. Said tool is held in a manner that enables it to rotate in the guiding bush and its horizontally displacement therein is limited by a cotter. The guiding bush includes at least one non-circular peripheral area that interacts with an area having a complementary shape that is made in the front of the casing in order to limit the rotation of the bush and thus of the body relative to the casing.

Abstract: The invention relates to a bucket-, claw-, scraper-blade- or compacting-type attachment (1) which is intended to be fitted at one end (18) of a rock breaker (15) comprising a tool (17). The inventive attachment comprises: (i) means (7, 8, 9, 12) enabling the correct positioning thereof in relation to the rock breaker and the tool; and (ii) means (13, 14, 20) for fixing same temporarily and removably to the end of the rock breaker, without dismantling the tool (17).

Abstract: The tool mounted in a body of an apparatus is retained by a cotter engaging inside a notch of the tool, the cotter being engaged in a borehole of the body. The area of the body containing this borehole for engagement of the cotter is equipped with a covering ferrule. This ferrule is provided for occupying a first position in which it at least partially occludes the borehole and a second position in which the borehole is cleared for enabling the cotter to be inserted or removed.

Abstract: The ramming device comprises a ramming element to be assigned to the end of a rock breaker. The inventive device receives the shocks generated by the rock breaker and transmits them to fragments to be compacted. The ramming device also has a frame comprising: positioning means for positioning relative to the rock-breaker so that the axis of the frame is coincident with the axis of the rock breaker; joining means that enable the temporary and removable fixing of the frame to the end of the rock breaker; axially translational guiding means for guiding the ramming element relative to the frame; means for blocking the rotation of the ramming element about the axis of the frame, and; means for limiting the amplitude of this translation.

Abstract: A hydraulic rotary percussive hammer drill includes a body containing a reciprocating percussion piston sliding under the effect of a main hydraulic supply circuit, this main circuit also being intended to cause the sliding of a roughly annular abutment piston housed in a cavity of the body, and having, on the one hand, a front face in contact with a shank and intended to place this shank a predetermined distance away from the percussion piston and, on the other hand, a rear face facing a rear wall of the cavity, characterized in that an external hydraulic supply circuit is able, when the main circuit is shut down, to introduce fluid under pressure between the rear face of the abutment piston and the rear wall of the cavity so as to maintain a space between these items.

Abstract: The inventive device includes a casing, inside of which the body is accommodated that has the hydraulic striking mechanism, inside of which a bush is mounted for guiding a tool. Said tool is held in a manner that enables it to rotate in the guiding bush and its horizontally displacement therein is limited by a cotter. The guiding bush includes at least one non-circular peripheral area that interacts with an area having a complementary shape that is made in the front of the casing in order to limit the rotation of the bush and thus of the body relative to the casing.

Abstract: A percussive apparatus comprises a body inside of which a striking piston is mounted in a cylinder bore. Two axially offset pieces are mounted inside the cylinder bore of the body while being concentric to the piston, and a deformable washer is placed between said pieces. One of the pieces is stationary with regard to the other piece that, however, is mounted in a manner that enables it to slide inside the cylinder bore and to be displaced in the direction of the stationary piece while being subjected to the action of the supply pressure of the hydraulic fluid that acts upon the surface of the moving piece facing away from the side opposite the stationary piece. The displacement of the moving piece causes the elastic washer to deform in order to create a passage with a variable cross-section on the return circuit of the hydraulic fluid to the reservoir or on a circuit that diverts, to the return circuit, a portion of the delivery flow of the apparatus whereby regulating the input pressure.

Abstract: The invention concerns an apparatus comprising a body (1) containing a cylinder wherein is mounted sliding an impact piston (1) of a tool, the motion of the piston being controlled by a distributor (15) which, arranged coaxial to the impact piston, is mounted inside a distribution box (3). The distribution box (3) comprises a part axially overlapping the piston (1) and arranged concentric thereto, and the distribution box (3) defines with the piston a control chamber (13) which, successively put under the high (9) and the low (12) pressure of the fluid, communicates through a passage (16) arranged in the distribution box (3) with a chamber controlling (14) the movement of the distributor (15), to generate alternately low pressure and high pressure.

Abstract: A device for supplying hydraulic power to a rotary apparatus for percussive drilling (2) whereof the tool (3) is driven in one direction or another and subjected to the action of an impact device (6) acting independently of the rotation, of a hydraulic device (9) with forward movement enabling the tool to generate a pressure force on the ground, and optionally of a suction device (14) for the drilling dusts, driven by a hydraulic motor, the various hydraulic actuating elements being driven from a hydraulic liquid source under pressure through a hydraulic flow divider (16), a set of distributors (17, 18, 19, 20) and an assembly of branch pipes outside the apparatus, such as hose pipes. The device includes a branch pipe external to the apparatus (24) for communicating the return branch pipe (22) of the hydraulic device (4) driving the tool in rotation and the supply line (23) of the impact device (6), to add to the supply rate of the impact device the return flow rate of the rotation driving device.

Abstract: The invention concerns an apparatus comprising a body (2) wherein a piston (6) is mounted sliding alternately driven by an incompressible fluid under pressure, said body containing part of a tool (4) which is guided in translation in a wear sleeve (3), the end of the tool located inside the body being subjected to the repeated impacts of the piston (6), while the other end projects beyond the body and is designed to be supported on the rock or analogue to be destroyed, the tool being retained in the body by at least a transverse key (13). One of the keys (13) retaining the tool passes through aligned holes provided in the body (2), into the wear sleeve (3), and overlaps inside the inner cylindrical space of the sleeve, the tool (4) having a transverse groove (12) for the key (13) to pass through.

Abstract: A percussive hydraulic apparatus includes a body inside which is mounted a cylinder in which an impact piston is guided. Fluid distribution providing the motion of the piston is produced by a distributor housed in a distribution box mounted in the body. The cylinder and the distribution box are entirely contained in the enclosure defined by the body, with the cylinder being mechanically supported by one of its ends of the body. The distribution box is mounted coaxial to the cylinder and is mechanically supported thereon. Surfaces perpendicular to the axis of the apparatus, subjected to pressure, are arranged and dimensioned such that the resultant hydraulic forces applied on the cylinder and distribution box during all the phases of the operating cycle thereof are directed in the same direction towards a support located in the body of the apparatus.

Abstract: Drilling device, of the type possessing a drilling unit of which the tool is driven to rotate from a hydraulic motor associated with an advancing device enabling a bearing force of the drilling unit on the ground to be created, the various actuating members being driven from at least one hydraulic pump via a set of hydraulic distributors and a set of tubes, such as hoses, the two feed tubes of the advancing device of the drilling system being equipped with a switch for reversing the direction of circulation of the fluid in the advancing device.

Abstract: Method and apparatus for controlling a percussive machine by determining, during the phase of rebound of a piston following impact, the existence of an instantaneous flow rate of fluid flowing from a top chamber toward the high-pressure fluid feed circuit. The instantaneous flow rate is determined on the basis of the differential pressure between the top chamber and the high pressure fluid feed circuit. If a flow rate is detected, a control device is fed with pressurized fluid so as to shift a selector piston in a direction for lengthening the stroke of the striking piston.