Abstract: A rock drill for percussive drilling includes a shank, a collar connected to a front end of the shank, and a rod portion which at one end connects to the collar while the other end carries a rock cutting means. A central flush channel extends from the front free end of the shank in a direction towards the front end. The central flush channel has a substantially constant diameter (d) along essentially its entire length; a ratio of the diameter (d) to a smallest outer cross sectional width (D) of the rod portion being in the range of 0.35 to 0.43.

Abstract: A percussion drill bit for drilling bores, comprises a drill body having a plurality of gauge row inserts embedded in a front end of the drill body. Each gauge row insert comprises a cemented carbide body having a mounting portion embedded in the drill body, and a front end protruding from the drill body. A polycrystalline diamond layer is provided on the front end of the carbide body. The diamond layer has a rear edge disposed in the vicinity of a maximum diameter of the insert. That rear edge is spaced from the wall of the bore during drilling by tilting the gauge row insert at an acute angle of 41.degree. to 51.degree. relative to the rotational axis of the drill bit. The front end of the carbide body is defined by a radius whose origin lies on a center axis of the insert. That origin is disposed axially rearwardly of a plane containing the rear edge of the diamond layer. The length of that radius is 50% to 52% of a diameter of the mounting portion of the insert.

Abstract: A down-the-hole rock drill includes a top sub, a driver sub having a bore therein, and a piston case extending between and detachably connected to the top sub and the driver sub. A piston is located within the piston case, and a drill device is detachably connected to the driver sub. The drill device includes a shank and a head. The drill device also has a central passageway for a flushing medium. A tube is secured in the central passageway at a free end of the shank. The tube extends beyond the free end of the shank, and the piston has a central piston passageway that receives the tube. The piston is slidably movable relative to the tube. A first portion of the shank located closest to the head has a cross section, normal to a longitudinal center axis of the shank, in the shape of a multi-lobed figure that is continuously non-concave, and the bore of the driver sub is of a matching cross-sectional shape.

Abstract: The present invention related to a drill bit (10) for rock drilling, preferably a down-the-hole drill bit, said drill bit (10) including a head (11) and a shaft (12), said head (11) defining a cutting face (14) that carries a number of hard material button inserts (15) having end portions extending outwardly of said cutting face (14), means (16,17) for transporting flushing medium from the free end (13) of the shaft (12) to the cutting face (14) of the head (11), said means for transporting flushing medium including a central passage (16) extending from the free end (13) of the shaft (12) and terminating in the head (11) short of the cutting face (14) and at least one branch passage (17) emanating from the central passage (16) and emerging in the cutting facc (14).In the field of down-the-hole drill bits big volumes of flushing medium, normally compressed air, are used since the flushing medium is also activating the down-the-hole hammer.

Abstract: A down-the-hole drill tool comprises a one-piece shaft and pilot bit. The shaft is adapted for connection to a down-the-hole hammer. A reamer and a guide body are detachably mounted to the one-piece shaft/pilot bit. The guide body has a downwardly facing shoulder for pushing a casing tube downwardly along with the tool.

Abstract: A tool for cutting solid material includes a tool body having a recess, and a cutting insert received in the recess. The cutting insert has spacing buttons which engage a surface of the recess to create a space for accommodating a brazing material which secures the insert to the tool body. The surface of the recess includes an annular retaining groove which receives the buttons in order to prevent tilting of the insert prior to brazing.

Abstract: The present invention relates to a tool for cutting solid material, the tool including a tool body having a supporting surface, and a cutting insert having a generally conical tip portion and a shoulder portion that is intended to rest against a supporting surface, the cutting insert being secured to the tool body, e.g., by brazing. The invention also relates to the cutting insert per se. The cutting insert has a concave portion between its tip and bottom which concave portion extends circumferentially around the cutting insert. In addition, a special type of cemented carbide is used for the cutting insert.

Abstract: A tool is mounted in a holder, the holder including a fluid passage for discharging drilling fluid toward a cutting zone. Fluid flow is regulated by a valve in the holder. The valve includes a housing and a valve element movable in the housing. The valve element opens the valve in response to rearward displacement of the tool relative to the holder. The housing of the valve is also rearwardly displaceable relative to the holder whenever rearward forces transmitted from the tool are excessive, thereby avoiding the occurrence of damage to the valve. The valve housing is yiealdably biased forwardly by fluid pressure in the conduit.

Abstract: A tool for breaking, cutting, and working solid materials includes a rearwardly extending shaft adapted to be inserted into the bore of a holder. The shaft includes an annular groove located adjacent a rearmost end thereof. A cylindrical clip is mounted on the shaft for retaining the tool within the holder. The clip includes a longitudinal slot extending longitudinally completely therethrough. A rear free end of the clip is inwardly bent into the groove of the shaft to oppose longitudinal forward movement of the shaft relative to the clip.

Abstract: A cutter (10) intended for use on a planing blade on a road planing machine is provided with a plurality of tools (14) rotatably mounted in the cutter. The tools (14) are mounted side by side and are adapted to carry out the working of the road surface (17).

Abstract: A device for supplying fluid at a socket for axial not displaceably mounted tools for breaking of solid material, fluid is arranged to be supplied to a nozzle adjacent to the tool when a working tool is subjected to a counteracting force.

Abstract: The invention relates to a device for supplying fluid to a tool for breaking solid material, said tool being mounted in a holder, and that a nozzle is arranged in or in connection to the tool. A connection element for fluid transmission is arranged to bridge the opposing contact surfaces on the holder and the machine part in such a way that fluid is prevented to enter between said contact surfaces.