Abstract: The invention relates to drilling or rockbolting machines, for the execution of underground works, in particular in mining operations. The carrier vehicle comprises a chassis and four wheels, all driving wheels, with two wheels situated on the right-hand side of the chassis of the vehicle and two other wheels situated on the left-hand side of the chassis. The four wheels are of the independent suspension type, having a jack-controlled height, and each comprise rotation-drive means, especially hydraulic motors. The chassis receives, at the front and at the rear, working equipment, such as drilling arms with respective guides, the basic position of which is horizontal and transverse to the direction of displacement of the vehicle. This carrier vehicle is applicable to the realization of a machine, which can be used in mine galleries of low height.

Abstract: The drilling and bolting head (7) of compact structure, is designed for use in mine galleries of small height. It comprises: a transverse table (8) connected to the carrying vehicle, preferably with a device (9 to 12) for lifting this table (8); a slide (13) displaceable along the table (8); an intermediate support (16) displaceable vertically on the slide (13); a vertical beam (21) mounted pivotally on the intermediate support (16); a vertical slideway (23) guided vertically on the beam (21); a drill (26), with a device (33, 34) for the drilling and setting of bolts, which is guided vertically on the slideway (23); motorized device (14, 18, 30) for controlling the various movements. The intermediate support (16) possesses an upper part (20) which can be used as a prop, in combination with a jack (18) arranged along the vertical pivot axis (19) of the beam (21).

Abstract: The drilling and bolting head (7) of compact structure, is designed for use in mine galleries of small height. It comprises: a transverse table (8) connected to the carrying vehicle, preferably with means (9 to 12) for lifting this table (8); a slide (13) displaceable along the table (8); an intermediate support (16) displaceable vertically on the slide (13); a vertical beam (21) mounted pivotally on the intermediate support (16); a vertical slideway (23) guided vertically on the beam (21); a drill (26), with means (33, 34) for the drilling and setting of bolts, which is guided vertically on the slideway (23); motorized means (14, 18, 30) for controlling the various movements. The intermediate support (16) possesses an upper part (20) which can be used as a prop, in combination with a jack (18) arranged along the vertical pivot axis (19) of the beam (21).

Abstract: The invention relates to drilling or rockbolting machines, for the execution of underground works, in particular in mining operations. The carrier vehicle comprises a chassis (2) and four wheels, all driving wheels, with two wheels (4) situated on the right-hand side of the chassis (2) of the vehicle and two other wheels (5, 6) situated on the left-hand side of the chassis. The four wheels are of the independent suspension type, having a jack-controlled height, and each comprise rotation-drive means, especially hydraulic motors. The chassis (2) receives, at the front and at the rear, working equipment, such as drilling arms (25, 26) with respective guides (27, 29), the basic position of which is horizontal and transverse to the direction of displacement (F) of the vehicle. This carrier vehicle is applicable to the realization of a machine which can be used in mine galleries of low height.

Abstract: A fluid-powered hammer drill has a bore in which a tool shaft is normally coaxially engaged. A piston displaceable in the bore defines a front return chamber of small effective piston surface area and a rear drive chamber of larger effective surface area. A passage permanently connects the front chamber with the high-pressure side of a pressure source. A reversible control valve is connected between both sides of the source and the rear chamber for alternately pressurizing and depressurizing same and thereby alternately displacing the piston axial forward to strike the rear end of the tool shaft and axially backward. A recoil-damping sleeve surrounds the piston axially ahead of the front chamber and has a front end axially forwardly engageable with the tool shaft in a frontmost position and a rear end defining with the bore a recoil chamber separate from the front return chamber. The housing is formed with a vent passage connected to the low-pressure side of the source and opening into the recoil chamber.

Abstract: A hydraulic percussion apparatus has an elongated housing having a front nose piece and forming a chamber extending along an axis, a tool projecting axially backward through the nose piece into the housing and having in the nose piece an axially forwardly directed shoulder, and a piston axially reciprocal in the chamber and axially forwardly engageable with the tool. A high-pressure line, a low-pressure line, and a control valve can axially oppositely pressurize the piston and thereby hammer the piston against the tool. A sleeve surrounding the tool in the nose piece is displaceable axially in the nose piece between a full-forward end position axially forwardly abutting the housing and a full-rear end position axially abutting the housing and through an intermediate position between the end positions. This sleeve is formed with a radially outwardly open groove defining in the nose piece a damping compartment.