Abstract: The present invention provides a novel drill insert having chipbreakers, or chip splitting grooves formed through the cutting surfaces. The cutting tool insert has a specialized geometry including a chip splitting groove formed at a negative rake angle. The chip splitting grooves increase the cutting efficiency of the tool while allowing the edge strength to be increased while also allowing higher feed rates.

Abstract: A rotatable tool for chip removing machining having a rotatable holder part and a cutting part that is detachably connected to a front end of the holder part. In a front end portion of the holder part, a forwardly open slot is formed, which separates two elastically flexible branches of the holder part. For clamping of the cutting part on the holder part, a male/female coupling is arranged, which comprises a centrical, male-like pin on one of the parts and a corresponding seat in the other part. Disposed on the holder part radially outside of the male/female coupling are thrust load carrying support surfaces, which surfaces are at least partially conical and are engaged by corresponding support surfaces of the cutting part. During a cutting operation, axial thrust loads transmitted to the axial thrust support surfaces cause the branches to be pressed in a direction intensifying the radial contact between the pin and the seat.

Abstract: Rotatable tool for chip removing machining includes a rotatable holder part and a cutting part that is detachably connected to a front end of the holder part. In the front end of the holder part, a forwardly open slot is formed, which separates two elastically flexible branches of the holder part. For clamping of the cutting part on the holder part, a male/female coupling is provided, which comprises a pin on either the holder part or the cutting part and a corresponding pin-receiving seat in the other part. If the pin is on the holder part, then a manually induced elastic deformation of the branches towards one another reduces the diameter of the pin to enable the pin to enter the female part. Subsequent return of the branches toward a rest state thereof causes the diameter of the pin to expand and tightly hold the cutting part.

Abstract: This invention describes a drilling plate and bracket for the drilling plate for machining drilled holes in work pieces, whereby the bracket for the drilling plate is designed so that it is somewhat pin-shaped and holds the drilling plate on its front side. It is characterized in that the drilling plate (1) is designed with an enlarged sheet thickness in the area of the cutting geometry in which chip breaking contours (15, 16, 20) are formed.

Abstract: A rotary chip-removing tool includes a rotary tool body and a tool tip fastened on a front end thereof. The tool tip is formed of an injection molded body which has an integral cutting edge at its front end, and a coupling structure at its rear end. The coupling structure can be in the form of a threaded hole, or a rearward projection, for coupling the tool tip against the tool body. The tool tip is formed of first and second materials. The first material forms at least part of the cutting edge, and the second material forms the coupling structure. The first material is more brittle than the second material, and the second material is tougher than the first material.

Abstract: A deburring tool capable of removing burrs and placing chamfers on circumferential edges surrounding both front and back side openings of a borehole, wherein the tool includes an elongated cylindrical arbor, a resilient arm section, and a replaceable cutting insert. In use, the rotating deburring tool is steadily advanced in a forward axial direction until the replaceable cutting insert encounters the circumferential edge of a front side opening, whereby the tool removes any burrs and creates a chamfer on that opening. Continued forward axial movement causes the replaceable cutting insert to retract within the arbor such that the tool continues through the borehole without damaging its interior surface. As the tool emerges from the back side opening of the borehole, the replaceable cutting insert is again allowed to extend out of the arbor and into a deburring position.

Abstract: A rotatable tool has a replaceable tip mounted thereon. The tool includes a tool body having a cutting seat in which the tip is received. The tip has edges for chip removing machining. The cutting seat and the replaceable tip have mutually cooperating support surfaces extending transverse to the longitudinal center axis of the tool. The cutting seat and the replaceable tip have mutually cooperating guide surfaces which are symmetrical about the longitudinal center axis as well as clamp portions for clamping the replaceable tip in the axis direction of the tool. A locking screw is received in the tool body to bring the replaceable tip into cooperation with the clamping portions.

Abstract: A cutting insert for a during includes a broken main cutting edge, the ends of which join respective additional edges of the insert by curved nose portions. Each curved nose portion forms a curved cutting edge defined by at least three sequentially arranged curved cutting edge segments defined by respective radii of different sizes. A first of the segments joins one end of the main cutting edge and has a first radius. The next segment has a radius of different length than the first radius and projects farther laterally than the first segment to perform a wiping function.

Abstract: A tool tip and tool body assembly includes a tool tip having a first end for contacting a workpiece and a second end, the second end having a patterned surface of recesses and protrusions, and at least one through hole extending through the tool tip from the second end. A tool body has a first end having a patterned surface corresponding to the patterned surface of the tool tip for mating with the patterned surface of the tool tip, and at least one threaded hole adapted to align with the at least one through hole in the tool tip. At least one fastener having a threaded end and a securing end is provided, the fastener extending through the at least one through hole such that the securing end abuts against a surface in the at least one through hole, the threaded end mating with threads in the threaded hole. Torque is transmitted between the tool tip and the tool body solely by the at least one fastener and the patterned surface of the tool tip and the patterned surface of the tool body.

Abstract: The invention relates to a boring tool comprising a retaining device which extends in the direction of a longitudinal axis and which comprises a shaft section and a head section. A groove which runs orthogonal in relation to the longitudinal axis and in the direction of a transversal axis is configured in said head section. The boring tool also comprises a cutting insert which is inserted in the groove, and comprises a clamping element. Said clamping element passes through a receiving boring configured in the cutting insert and through a boring configured in at least one of the groove limbs. In addition, the clamping element clamps the cutting insert against the at least one groove limb.

Abstract: A rotary boring tool adapted to include a locator insert for precision positioning of cutting tips provided on multiple cutting elements or inserts is disclosed. The boring tool comprises a tool body, a plurality of replaceable cutting inserts and an insert locator. The tool body includes a first end having a shank portion and a second end having a plurality of cutter insert supports, a plurality of cutter insert recesses and an insert locator recess. The outside surfaces of the shank portion and the flat portions of the insert locator are jig ground to a 0.000 variance relative to a central rotational axis of the tool body. The insert locator is secured to the tool body at a base surface of the insert locator recess. The cutting inserts are secured to the second end of the tool body so that they contact base surfaces of the cutting insert recesses, first radially and axially extending lateral or side surfaces of the cutting insert supports, and the flat portions of the insert locator.

Abstract: A throw-away tip for use in drilling work that has a convexly curved cutting edge portion at one end side of a cutting edge is provided. Chips are prevented from being sheared and packed, and cutting edge strength is secured to extend the service life of the tip. The tip is used with a drilling tool having a tool body rotatable about an axis and has a convexly curved surface formed on a rake face thereof on the one end side of the cutting edge, which forms a curve toward a seat face thereof as it proceeds toward the one end side of the cutting edge.

Abstract: A separable rotary cutting tool is disclosed. The tool comprises a shank and a head. The shank has a receiver comprised of a shank guide at a trailing end of the receiver, opposing shank drive keys at a leading end of the receiver, and a shank locator located axially between the shank guide and the shank drive keys. The shank drive keys each comprises an axially extending shank drive key radial stop surface that is disposed at an angle relative to a plane extending through a central axis of the receiver. The head has a connector comprised of a head guide at a trailing end of the connector, opposing head drive keys at a leading end of the connector, and a head locator located axially between the head guide and the head drive keys. The head drive keys each comprises an axially extending head drive key radial stop surface that is disposed at an angle relative to a plane extending through a central axis of the connector.

Abstract: A reamer for the fine machining of surfaces of drilled holes in metal workpieces has a reamer body and at that body has at least one main blade and at least one auxiliary blade, a chip surface adjoining the blades at one side and a chip deflector step limiting the chip surface. That deflector step falls away in the zone of the auxiliary blade, exhibiting an increasing distance from the auxiliary blade. The chip deflector step rises in the zone of the main blade, exhibiting a decreasing distance from the main blade. The blades, chip surface and deflector step may be on a cutter plate attached to the reamer body or be part of the body itself. The invention also concerns that cutter plate.

Abstract: In a cylindrical drill bit comprising a tool body with a head having a front face and a cylindrical shaft for chucking the tool body, a hard metal cutting plate structure is mounted on the front face of the head and includes cutting edges formed integrally with the hard metal cutting plate.

Abstract: The present invention provides a new cutting tool assembly comprising a replaceable cutting head and a tool body having a common longitudinal axis and mating peripheral surfaces. The cutting head has a cutting portion forming a leading end, a pilot portion forming a trailing end, and a cutting head mounting portion adjacent the trailing end of the cutting head. The tool body has a cutting head receiving portion formed at a leading end of the tool body and a pilot recess disposed in the leading end of the tool body to matingly receive the pilot portion of the cutting head. The cutting head mounting portion and the cutting head receiving portion of the tool body each have at least two coupling portions. The cutting head coupling portions and the tool body coupling portions are bound by their peripheral surfaces and generally mate in shape and dimensions. Each coupling portion has a pair of base surfaces, including upper and lower surfaces.

Abstract: In order to improve durability, machining stability, machining accuracy, etc. of a throwaway cutting tool in which a cutting head having a cutting edge is detachably mounted to the tip of a tool body using a clamping tool so that its function can be regenerated by replacing the cutting head, protrusions 8, 16 having their height gradually increasing and recesses 9, 15 having their depth gradually increasing from the center toward outer periphery of the tool are formed alternately with each other in a radial arrangement on the front surface of the tool body 2 and a support surface of the cutting head 3, which is formed by sintering, respectively. The protrusions and recesses, which are provided so that their positions correspond to each other, are conically engaged, thereby centering the cutting head and preventing its movement.

Abstract: A drilling tool includes a shaft having a front end to which a cutting body provided with cutting edges is detachably connected. In the front end of the shaft, a seat is formed which is delimited by spaced-apart protrusions between which there is a bottom surface. In the protrusion, there is a threaded hole for a screw, which when tightened applies pre-stressing forces to the cutting body. On the inside of the opposite protrusion, there is a supporting shoulder against which the cutting body is pressed when the screw is tightened and applies a lateral pre-stressing force to the cutting body. The protrusions are laterally displaced in relation to each other in order to freely expose the screw beside one of the protrusions.

Abstract: The present invention provides a new cutting tool assembly comprising a replaceable cutting head and a tool body having a common longitudinal axis and mating peripheral surfaces. The cutting head has a cutting portion forming a leading end, a pilot portion forming a trailing end, and a cutting head mounting portion adjacent the trailing end of the cutting head. The tool body has a cutting head receiving portion formed at a leading end of the tool body and a pilot recess disposed in the leading end of the tool body to matingly receive the pilot portion of the cutting head. The cutting head mounting portion and the cutting head receiving portion of the tool body each have at least two coupling portions. The cutting head coupling portions and the tool body coupling portions are bound by their peripheral surfaces and generally mate in shape and dimensions. Each coupling portion has a pair of base surfaces, including upper and lower surfaces.

Abstract: A twist drill, having a replaceable drill tip, comprising a drill bit shaft (1), a cutting insert (2) which is detachably fixed thereto and which forms the tip area of the twist drill, and comprises a flute (3) that continues into the cutting insert (2). The cutting insert rests, with a bearing surface (6) extending orthogonal to the center longitudinal axis (8) of the drill bit, on the face (7) of the drill bit shaft (1) and extends with a fixing stud (9), which centrally protrudes from the bearing surface (6), into a receiving recess (10) which is configured complementary thereto and which is provided in the face (7) of the drill bit shaft (1).

Abstract: The present invention provides a novel drill insert having chipbreakers, or chip splitting grooves formed through the cutting surfaces. The cutting tool insert has a specialized geometry including a chip splitting groove formed at a negative rake angle. The chip splitting grooves increase the cutting efficiency of the tool while allowing the edge strength to be increased while also allowing higher feed rates.

Abstract: In a cylindrical drill bit comprising a tool body with a head having a front face and a cylindrical shaft for chucking the tool body, a hard metal cutting plate structure is mounted on the front face of the head and includes cutting edges formed integrally with the hard metal cutting plate.

Abstract: A throwaway tip comprises a base which is to be held between a pair of holder pieces of a holder. A cutting edge is provided on a front edge of the base. A pair of holder bearing faces to be respectively brought into abutment against the holder pieces are respectively provided on sides of the base. A rear bearing face to be brought into abutment against a bottom of a pocket of the holder is provided on a rear side of the base. The rear bearing face is substantially orthogonal to the holder bearing faces. Most of a thrust load exerted on the tip during a drilling operation is stably received by the bottom of the pocket.

Abstract: On a drill with a base body and a replaceable cutting insert, the cutting insert lies in a receptacle that runs through the base body at a right angle to the latter's longitudinal axis and is open toward the drill tip, whereby the cutting insert is in contact by means of two diametrically opposite contact surfaces against the side walls of the receptacle. Between each contact surface of the cutting insert and a side wall of the receptacle, there is a groove that extends in the direction of the longitudinal axis, in which groove a clamping wedge sits with a form-fit and a friction-fit, and interacts with the base body and the cutting insert in the manner of a self-locking device that acts toward the drill tip.

Abstract: This invention describes a drilling plate and bracket for the drilling plate for machining drilled holes in work pieces, whereby the bracket for the drilling plate is designed so that it is somewhat pin-shaped and holds the drilling plate on its front side. It is characterized in that the drilling plate (1) is designed with an enlarged sheet thickness in the area of the cutting geometry in which chip breaking contours (15, 16, 20) are formed.

Abstract: The present invention relates to a throwaway tip of single tip type having an inner cutting edge for cutting a center area of a hole being drilled and an outer cutting edge for cutting a circumference area of the hole, and to a drill holder for holding the throwaway tip. The tip is characterized in that a step gap between a first rake face and a second bearing face on the side of the inner cutting edge are spanned by a first curved surface, and the drill holder is characterized in that a connection surface thereof adjacent to the first rake face is inclined in the same direction as an inclination of the helix of a flute, whereby chip ejection is facilitated.

Abstract: A junction is proposed between two tool parts, where a first tool part has a recess in hollow cone shape, and a second tool part has a cone-shaped projection that can be inserted into the recess. The junction is characterized by the fact that the recess (7) and the projection (33) have practically the identical angle of taper, that the projection (33) is structured to be practically non-resilient, and the wall (9) that surrounds the recess (7) of the first tool part (holder (1)), is structured to be resilient, and that the two tool parts (1, 31) are provided with flat surfaces (23, 37) that rest against one another when the two tool parts (1, 31) are connected. It is essential that the two tool parts are secured together in the assembled state of the junction (1), in an axial direction by means of a clamping device in such a way that the wall (9) of the first tool part (1) is expanded.

Abstract: A rotatable cutting tool includes a rotatable tool body and a replaceable cutting tip for chip removing machining. The tool body includes a forward free end having a first dovetail coupling part formed thereon. The cutting tip includes a front cutting end and a rear mounting end. The mounting end includes a second dovetail coupling part joined to the first dovetail coupling part. An actuator, such as a screw, is provided which is arranged for elastically deforming one of the dovetail coupling parts to create a tightly clamped relationship between the first and second dovetail coupling parts. Insertion of a replacement cutting tip is performed by laterally mating the dovetail coupling parts until one of the coupling parts abuts a laterally facing stop surface of the other coupling part.

Abstract: In a machine tool, a cradle of a bit holder is in the form of a rectangular trihedron and is inclined transversely about an axis of inclination corresponding to a generatrix of the conical bearing surface of a valve seat that has to be produced, while the cutting edges of the bit are produced from a blank having three bearing faces forming a rectangular trihedron, including a back face, a longitudinal face and a rear face, and another longitudinal face and a forward face of which, remaining in the as-produced state, are flanks with respect to the front face, a main cutting edge being produced so that its mid-point coincides with a reference point on the axis of inclination and lies on the axis of inclination at a constant distance from the vertex of the trihedron of the cradle.

Abstract: A spade blade drill having blended open notch forms on either side of an apex. The notches transition into elliptical flutes which extend outwardly toward sides of the insert. The elliptical flute profiles inhibit chip curling and packing. The sides incorporate a pair of surfaces having a reduced clearance angle for preventing chip packing. The blended open notches are deep and extend across the entire width of the flutes, enhancing heat transfer surface area and allowing chips to flow along the entire flute surfaces. A plurality of chip splitters extend from the flutes across two relief surfaces. The chip splitters have a rounded profile, inhibiting chips from becoming hung in the splitters.

Abstract: A tool for chip removing machining includes a drill and a countersinker mounted thereto. The countersinker comprises two half-sections that are clamped to each other and to the drill. The drill includes helical flutes defining respective chip-removal channels. Each half-section includes a connection portion received in a respective flute of the drill. The connection portion has a shape generally corresponding to that of the chip flute, so as to be form-locked within the flute. Each connection portion includes a convex surface facing the flute, and a concave surface facing away from the convex portion. The convex surface can be pressed against the concave wall of the flute, whereby the concave surface forms a section of a wall of a respective chip-removal channel.

Abstract: A valve insertion method without stopping passage of fluid, wherein, first, a part of an already-installed pipe is enclosed air-tightly with a valve casing, a milling type cutting tool which has cutting edges on a free end surface and an outer circumferential surface thereof, and a gate being housed in the valve casing with the gate and the cutting tool fixed thereto. The gate and cutting tool are provided in positions spaced from each other in the axial direction of the already-installed pipe. A worker then feeds the cutting tool in the radial direction of the already-installed pipe as he has the cutting tool make cutting motions for cutting the pipe by the rotation of the cutting tool. The valve casing is then turned in the circumferential direction of the already-installed pipe as the cutting motions are kept made, whereby a cut groove cut in the direction of the range of the whole circumference of the pipe is formed.

Abstract: A cutting tool having a shank held in a chuck. Mounted in the shank is an insert holder and a carbide insert held therein. The insert holder extends radially beyond the shank, with the insert on its extended end. The insert can be adjusted as to radial extension, by swingable adjustment, and held in adjusted position by tightening the holder. A gear is provided for swinging the holder, and a visual dial is provided to show the position of adjustment.

Abstract: A reamer for the fine machining of surfaces of drilled holes in metal workpieces has a reamer body and at that body has at least one main blade and at least one auxiliary blade, a chip surface adjoining the blades at one side and a chip deflector step limiting the chip surface. That deflector step falls away in the zone of the auxiliary blade, exhibiting an increasing distance from the auxiliary blade. The chip deflector step rises in the zone of the main blade, exhibiting a decreasing distance from the main blade. The blades, chip surface and deflector step may be on a cutter plate attached to the reamer body or be part of the body itself. The invention also concerns that cutter plate.

Abstract: A tool for simultaneously machining multiple surfaces on a stationary workpiece can include a rotary tool body having multiple cutter assemblies spaced circumferentially around the tool body. Different ones of the cutter assemblies can include differently angled cutting elements for machining different frusto-conical surfaces in the workpiece. At least some of the cutting elements can have two separate cutting edges.

Abstract: In an interference fit type cutting tool according to the present invention, a head section and a shank section are fitted together by shrinkage fitting. The shank section is provided with a shaft portion and a taper portion. The head section is provided with a hole portion to be fitted on the shaft portion, and a tapered portion to be fitted on the taper portion. The hole portion and the tapered portion have an interference, and the inner diameters thereof are smaller than the outer diameters of the shaft portion and the taper portion. Two-surface restraint is established by fixing the shaft portion and the hole portion, and the taper portion and the tapered portion with the interference pressure by shrinkage fitting. A key is formed on the leading end face of the-shaft portion, a key groove is formed in the bottom face of the hole portion, and the key and the key groove are fitted together.

Abstract: A cutting insert for a during includes a broken main cutting edge, the ends of which join respective additional edges of the insert by curved nose portions. Each curved nose portion forms a curved cutting edge defined by at least three sequentially arranged curved cutting edge segments defined by respective radii of different sizes. A first of the segments joins one end of the main cutting edge and has a first radius. The next segment has a radius of different length than the first radius and projects farther laterally than the first segment to perform a wiping function.

Abstract: A drilling tool includes a shaft having a front end to which a cutting body provided with cutting edges is detachably connected. In the front end of the shaft, a seat is formed which is delimited by spaced-apart protrusions between which there is a bottom surface. In the protrusion, there is a threaded hole for a screw, which when tightened applies pre-stressing forces to the cutting body. On the inside of the opposite protrusion, there is a supporting shoulder against which the cutting body is pressed when the screw is tightened and applies a lateral pre-stressing force to the cutting body. The protrusions are laterally displaced in relation to each other in order to freely expose the screw beside one of the protrusions.

Abstract: A clamping mechanism for clamping a cutting head to an adaptor; the adaptor having a shank receiving bore and three forwardly slanted unthreaded through bores; the cutting head for clamping to the adaptor having a shank with three forwardly slanted threaded bores. The arrangement being such that with the shank inserted into the shank receiving bore the cutting head is clamped to the adaptor by three retaining screws which pass through the unthreaded through bores and are threadingly engaged by the threaded bores.

Abstract: A throwaway tip comprises a base which is to be held between a pair of holder pieces of a holder. A cutting edge is provided on a front edge of the base. A pair of holder bearing faces to be respectively brought into abutment against the holder pieces are respectively provided on sides of the base. A rear bearing face to be brought into abutment against a bottom of a pocket of the holder is provided on a rear side of the base. The rear bearing face is substantially orthogonal to the holder bearing faces. Most of a thrust load exerted on the tip during a drilling operation is stably received by the bottom of the pocket.

Abstract: The present invention relates to a throwaway tip of single tip type having an inner cutting edge for cutting a center area of a hole being drilled and an outer cutting edge for cutting a circumference area of the hole, and to a drill holder for holding the throwaway tip. The tip is characterized in that a step gap between a first rake face and a second bearing face on the side of the inner cutting edge are spanned by a first curved surface, and the drill holder is characterized in that a connection surface thereof adjacent to the first rake face is inclined in the same direction as an inclination of the helix of a flute, whereby chip ejection is facilitated.

Abstract: A helically fluted twist drill device is disclosed for cutting materials. The device includes a cylindrical core having a first diameter, a longitudinal axis and a first and a second extremity, the second extremity defining a cutting point. At least three portions extend helically outwardly away from the core so that the portions define a second diameter. The arrangement is such that adjacent portions define therebetween a helical flute. Each of the flutes has a flute surface which is of S-shaped configuration when viewed as a cross section disposed normal to the longitudinal axis, the cross section being viewed in a direction from the first towards the second extremity. Each of the portions further defines a helical bore connected to a source of a cutting fluid for permitting a flow of the cutting fluid through the bore towards the cutting point. The arrangement is such that in use of the device, the cutting fluid conveys the materials away from the cutting point through each flute.

Abstract: A replaceable cutting head is adapted for co-axial coupling thereof, along a coupling axis, with a tool shank in a self-clamping fashion. Both the cutting head and the tool shank have a mounting portion comprising a centering section and a positioning section. The centering section is formed with a peripheral centering surface which extends circumferentially with respect to the coupling axis and has a substantially conical shape at least at two portions thereof. The positioning section has at least two peripherally disposed and circumferentially extending and spaced apart positioning surfaces adapted for the provision of an axial support of the cutting head on the tool shank. Each positioning surface is inclined with respect to the coupling axis so that an axial distance therefrom to a broad end of the peripheral centering surface increases in a direction generally corresponding to the direction of cutting forces acting on the cutting edge during a cutting operation.

Abstract: A cutting tool or drill insert with chip control geometry comprising a body including a portion securable in a holder and a forward portion. The forward portion defining at least one cutting edge extending from the central axis of the body to an edge of the body. A chip groove is defined by the surface of the body adjacent to the cutting edge. The chip groove incorporates chip control geometry as spaced apart elongate projections.

Abstract: The invention relates to a friction and sinking cutting tool comprising a base member (2) to which a cutting blade (20) is exchangeably clampingly fixed by means of a clamping screw and which is adjustable in terms of its radial position by an adjusting member (40) through the intermediary of an adjusting means (30). The adjusting means (30) is a cutting blade carrier extending into a recess in the base member, and the adjusting member (40) is a differential screw which is in threaded engagement with the adjusting means. Alternatively, the adjusting means (30) can be a cutting blade carrier extending into a recess of the base member and the adjusting member (40) can be a ball member or clamping member which has automatic shape fitting engagement with a complementary recess in the adjusting means such that a movement of the adjustment member causes a movement of the cutting blade (20) in the same direction.

Abstract: A mechanism and method for adjusting the position of a cutting insert relative to the body of a cutting tool is disclosed. The mechanism of the invention comprises a pair of flexible cantilevered walls each defining a wall of cutting insert pocket in the body of a boring bar. A boring bar of the invention comprises a bar body having at least one pocket for receiving a cutting insert and a position-adjusting mechanism including a pair of flexible cantilevered walls each defining a wall of the pocket. In the method of the invention, a boring bar is provided having a plurality of pockets each defined by a pair of cantilevered walls adapted to be flexed by a wedge mechanism. Next, a cutting insert is installed into each pocket. The position of the cutting edge of each cutting insert is then determined. In the last step of the method, the radially inwardmost insert is adjusted outward by using the wedge mechanism to flex the cantilevered walls.

Abstract: A drilling tool including a substantially columnar tool body rotatable about an axis, the tool body having a chip discharge groove formed in the outer periphery thereof opened at a distal end surface of the tool body; and a cutting edge having a rake face and extending from an end adjacent to the axis toward the outer periphery of the tool provided along a crossing ridge between a wall surface of the chip discharge groove facing in a circumferential direction of the tool and the distal end face. In the drilling tool, a concave surface rises in the circumferential direction of the tool with respect to the rake face of the cutting edge, the concave surface forming a concave curve advancing toward the distal end face of the tool in the circumferential direction of the tool, the concave surface being formed between the crossing ridge and the distal end face.

Abstract: A drilling tool includes a tool main body having a cutting edge at its forward end, a groove provided in the outer peripheral surface provided at the forward end of the tool main body, a cartridge accommodated in the groove and capable of elastic deformation in a radial direction of the tool main body, and a burr removing tip in the form of a substantially triangular flat plate detachably mounted to the cartridge and capable of protruding from and retracting into the outer peripheral surface of the tool main body. The cartridge is equipped with two holding walls which are in face contact with the two side surfaces of the three side surfaces corresponding to the three sides of the triangle formed by the burr removing tip. The two side surfaces of the burr removing tip are in face contact with the two holding walls, and the remaining one side surface is mounted to the cartridge in an open state.

Abstract: A cutter insert for a tool for the finish machining by chip removal of bore surfaces in workpieces is proposed, the cutter insert being inserted in a recess introduced into the peripheral surface of the tool and being held by means of at least one clamping shoe which interacts by means of a clamping lip with at least one clamping surface of the cutter insert, which is distinguished by the fact that the cutter insert, which preferably has a substantially rectangular configuration, has a hypothetical center line (39) with which the clamping surface (21; 21′) encloses an acute angle (&agr;; &agr;′).

Abstract: A spade drill is provided including a V-shaped drill cutting end and a pair of reaming edges on each side thereof. The reaming edges have a relatively large radius of curvature and generally define a flat portion at the apex of the reaming edges. The junction between the drill cutting end and the reaming edges has a misblended radius.