Abstract: A multi-flute reamer includes a cutting portion having a forward end and a rearward end, and a chip flute with a chip gash opening, and a cutting insert mounted on the cutting portion. A leading edge is formed at an intersection between a top surface and a radially-outward side surface, and a front edge is formed at an intersection between the top surface and a forward side surface. The cutting insert includes a rounded lead cutting edge formed at the intersection between the leading edge and the front edge, and the top surface includes a chip breaker having a bottom surface formed with a radius, R.

Abstract: The drill bit comprises a cutting blade formed at one end of a shank. The cutting blade has a pair of cutting shoulders that extend inwardly from the outer sides of the blade toward the bit axis. A tip having converging sides that create a point extends from the shoulders. The cutting edge of each shoulder is beveled with respect to the plane of the face of the blade. A flute is provided on the leading portion of each blade face adjacent the cutting edges. Each flute is a smooth curve that creates a substantially uninterrupted recess on each face of the blade that facilitates chip removal, increases the drill rate and lowers the power required to drill a hole. A non-stick coating may be applied to the blade to further facilitate chip removal.

Abstract: Chips are segmented to have a desired width and the chip controllability is improved and the tool rigidity is improved. A drilling tool is provided that includes: a tool body; a chip discharge groove formed at the outer periphery of the tool body; at least one sub-groove formed at an inner face facing the front side in the tool rotation direction T of the chip discharge groove; a rake face; a tip end flank face; and a cutting edge formed at a ridge line at which the tip end flank face intersects with the rake face. The plurality of rake faces form a step-like shape having at least one step section. The drilling tool is configured so that the turnup section of the sub-groove is turned up in a different direction from the direction along which the turnup section of the chip discharge groove is turned up.

Abstract: An indexable drill includes an insert attachment seat and a chip discharging groove formed so as to extend from a leading end surface to a trailing end side of the drill in the direction of the axis of rotation and through which chips generated by the cutting insert are discharged, and in that a wall surface defining the chip discharging groove at least partly includes a smoothed surface with a surface roughness of at most 0.5 ?m in terms of arithmetic average roughness Ra, the wall surface of the chip discharging groove is partly formed on a thinned wall portion thinned by the central edge attachment seat and the outer peripheral edge attachment seat, and a crossing portion between the first wall surface and the second wall surface in the thinned wall portion is rounded.

Abstract: The invention relates to a multi-edged machining tool for the post-machining or precision machining of bores. The tool has at least one cutting insert with a pre-determined nominal diameter measurement and with cutting edges that are distributed substantially uniformly around the periphery, in addition to a guide body assembly that is axially offset in relation to said edges. The guide body assembly can be an integral component of a substantially cylindrical guide body that consists of a solid carbide. In some embodiments, said guide body forms at least n helical guide ribs which are equidistant around the periphery and which have a nominal diameter substantially smaller than the nominal diameter measurement of the cutting insert by a value equating to double the dimension of the lubricant gap that is formed during the operation of the tool.

Abstract: The invention relates to a drilling tool (1) comprising a support shank (2) and an interchangeable cutting insert (3) which is fitted to the support shank (2) and which has an asymmetrical main lip (15) divided into a guide lip (10) having a supporting land (12) and a guide land (23) trailing the supporting land (12), and into a clearance lip (13) having a trailing clearance portion (14), wherein a guide land (28) and a supporting land (29) are formed on the lateral surface of the support shank (2) and continuously extend the guide land (23) and the supporting land (12), respectively, on the cutting insert (3) and additionally guide the drilling tool (1) on the inner wall of a drill hole during a drilling operation.

Abstract: A tool comprising a cutting section, on which a multiplicity of blades or cutting edges and flutes are formed; a shank section, which forms a chucking section on a side which faces away from the cutting section, wherein a number of fluid channels which corresponds to the number of flutes is formed in the chucking section, which channels in each case have an axial discharge opening and lead along the shank to an associated flute of the cutting section. Also, a method for supplying the blades of such a tool with a pressurized fluid.

Abstract: The invention relates to a drill tip (2) comprising a base body (6) having chip flutes (22A,B) and extending in the axial direction along an axis of rotation (8) and having at least two main cutting edges (14A,B) on the front face thereof extending outward in the radial direction to a cutting corner (16A,B). Seen in cross section, the base body is asymmetric relative to rotation about the axis of rotation (8) at the height of the cutting corner (16A,B). The cross section of the base body is simultaneously designed having symmetrical spacing from the main cutting edges (14A,B). The drill tip (2) is in particular designed as an interchangeable modular part of a modularly designed drill tip (5). A drill base body (4) in which the drill tip (2) can be inserted can therefore in turn be designed symmetrically.

Abstract: A metal cutting tool has a cutting head releasably mounted on a front end of a tool shank, in a self-clamping manner. The tool shank's forward end is provided with a pair of shank coupling portions, each having a forwardly facing shank support surface. A pocket recess is defined between the shank's coupling portions. Within the pocket recess are a plurality of shank fixation surfaces which are parallel to a longitudinal axis of the tool shank. The cutting head has a cap portion and a fixation portion extending in rearward direction therefrom. The cap portion includes a pair of head segments, each having a rearwardly facing head base surface. The cutting head's fixation portion has a plurality of head fixation surfaces which are parallel to a longitudinal axis of the cutting head.

Abstract: A reusable low cost drill bit element for operative, removable attachment to a turning implement for drilling anchor installation holes, particularly of at least ½? diameter, in drywall. The drill bit is comprised of a section to be engaged with the turning implement and to be turned therewith, a drilling section with angled step sections in common planes perpendicular to the drill bit axis to perpendicularly bore into the drywall and form a perpendicular through aperture of a desired diameter, and an element to prevent the drill bit from falling behind the wall so that it can be reused to bore additional holes for other anchor.

Abstract: A surgical rotary reamer including a shaft and a cutting head connected to the shaft. The cutting head has a plurality of cutting teeth. At least one cutting tooth has a forward portion, a rearward portion and a mid-portion therebetween. The forward portion has a first cutting edge that cuts in a first rotary direction. The rearward portion has a second cutting edge that cuts in the first rotary direction and/or a second rotary direction. The mid-portion interconnects the forward portion and the rearward portion and includes a recessed portion.

Abstract: A cutting tool for drilling has cutting inserts in the same shape and is capable of discharging a chip in a chip flute. The cutting tool includes: a body having a lower end facing a direction of drilling, a central axis of rotation and at least two chip flutes; and indexable inner and outer cutting inserts each disposed in an insert pocket formed at the lower end of the body and at a forward end of a corresponding chip flute. The inner cutting insert is located closer to the central axis of the body than the outer cutting insert. The inner and outer cutting inserts have the same shape and include lower cutting edges for depth cutting during drilling. The lower cutting edge of the inner cutting insert is disposed lower than the lower cutting edge of an imaginary cutting insert at a position where the inner cutting insert is overlapped with the imaginary cutting insert where the outer cutting insert is rotated by approximately a half-turn relative to the central axis.

Abstract: A guide portion prevents the drilling hole from curving due to a skipping rope phenomenon, and also prevents the inner wall face of the drilling hole from being damaged, so that its surface roughness can be improved. Chip evacuating flutes 4 are formed in the periphery of a drill body 1 which has a stick shape and is rotatable on its axis O, from its front flank 3 toward the rear side. Cutting edges 2A are formed along ridge lines where the front flanks 3 intersect with wall faces 4A which are in the chip evacuating flutes 4 and face in a drill rotational direction T. A cutting edge section 2, where the cutting edges 2A are formed, is provided in the front side of the drill body 1. A cutting edge section 2 has an external diameter which is smaller toward the rear side in the axis O direction than the external diameter D at the cutting edges 2A. A guide portion 6 has a maximum external diameter part 6A at the front periphery side, and is provided to the rear side of the cutting edge section 2.

Abstract: A rotary cutting tool includes a generally cylindrical body having a first end, a second end and a longitudinal axis therebetween. A mounting portion is disposed about the first end, a head portion having an outer diameter is disposed about the second end, and a body relief portion having an outer diameter less than the head portion is disposed therebetween. The head portion is structured to engage and cut a workpiece. A number of flutes extend from the second end of the cylindrical body along the head portion and along at least a portion of the body relief portion. The head portion includes a number of margin relief surfaces, each disposed between adjacent flutes and inset a distance from the outer diameter of the head portion and extending from the second end of the cylindrical body and terminating at a margin seal within the head portion.

Abstract: Drill with a straight chucking groove, with a convexly curved main cutting edge with, adjacent to the main cutting edge, a convexly designed region of groove base and with, adjacent to the convexly designed region of the groove base, a concavely designed groove base or a concavely curved main cutting edge with, adjacent to the main cutting edge, a concavely designed groove base with, adjacent to the concavely design region of the groove base, a convexly design region of the groove base.

Abstract: The drill bit comprises a cutting blade formed at one end of a shank. The cutting blade has a pair of cutting shoulders that extend inwardly from the outer sides of the blade toward the bit axis. A tip having converging sides that create a point extends from the shoulders. The cutting edge of each shoulder is beveled with respect to the plane of the face of the blade. A flute is provided on the leading portion of each blade face adjacent the cutting edges. Each flute is a smooth curve that creates a substantially uninterrupted recess on each face of the blade that facilitates chip removal, increases the drill rate and lowers the power required to drill a hole. A non-stick coating may be applied to the blade to further facilitate chip removal.

Abstract: A reamer for the precision machining of a drilled hole, having a plurality of cutting bars which are separated from one another by chip grooves and extend in the longitudinal direction of the tool, wherein a plurality of chip divider grooves which run in the transverse direction of the tool and divide each cutting bar into cutting segments are provided.

Abstract: A drill bit, has a front side (5) and a circumferential surface (19) adjoining the front side (5). The front side (5) has a main cutting edge (7) including a transverse cutting edge (3) extending through a center axis (11) of the drill bit (1), and has two first and second main cutting-edge regions (13, 15) adjoining the transverse cutting edge (9) and extending radially toward the circumferential surface (19). The circumferential surface (19) comprises at least two chip flutes (21, 23), which between them delimit a first and a second web (25, 27), and three lands, of which a first land adjoins the end of the first main cutting-edge region (13) facing away from the transverse cutting edge (9), and serves as a free cutting-edge land (33), and additionally has a free cutting edge (39), a second land adjoins the end of the second main cutting-edge region (15) facing away from the transverse cutting edge (9), and serves as a guide land (35), and a third land serves as a support land (37).

Abstract: A twist drill includes a cutting portion and a drill body. The cutting portion has a chisel edge, a segment relief surface, a chamfer relief surface and at least two flutes extending longitudinally to the drill body. Each flute has a rake surface and a gash extending away from the chisel edge. The cutting portion further has at least two cutting segments, each cutting segment having a first curved cutting edge, a second curved cutting edge and a chamfer cutting edge.

Abstract: The drill bit comprises a cutting blade formed at one end of a shank. The cutting blade has a pair of cutting shoulders that extend inwardly from the outer sides of the blade toward the bit axis. A tip having converging sides that create a point extends from the shoulders. The cutting edge of each shoulder is beveled with respect to the plane of the face of the blade. A flute is provided on the leading portion of each blade face adjacent the cutting edges. Each flute is a smooth curve that creates a substantially uninterrupted recess on each face of the blade that facilitates chip removal, increases the drill rate and lowers the power required to drill a hole. A non-stick coating may be applied to the blade to further facilitate chip removal.

Abstract: The drill bit comprises a cutting blade formed at one end of a shank. The cutting blade has a pair of cutting shoulders that extend inwardly from the outer sides of the blade toward the bit axis. A tip having converging sides that create a point extends from the shoulders. The cutting edge of each shoulder is beveled with respect to the plane of the face of the blade. A flute is provided on the leading portion of each blade face adjacent the cutting edges. Each flute is a smooth curve that creates a substantially uninterrupted recess on each face of the blade that facilitates chip removal, increases the drill rate and lowers the power required to drill a hole. A non-stick coating may be applied to the blade to further facilitate chip removal.

Abstract: A short-hole drill, including a drill body being rotatable about a center axis and having a rotationally symmetrical envelope surface, one or more replaceable cutting inserts mounted in pockets in a front end of the drill body, one or more outwardly open flutes being countersunk in the envelope surface and extending rearwardly from the front end of the drill body to evacuate chips from the cutting inserts, and a number of replaceable first support pads being mounted in countersunk seats proximate the front end of the drill body to support and guide the drill against a hole wall generated by the cutting inserts. A number of second support pads are mounted in countersunk seats that are axially spaced apart from the first support pads by an envelope surface portion having a predetermined axial extension to support and guide the drill when the first support pads leave the hole wall.

Abstract: A rotary cutting tool that is composed of a tool shank with at least one chucking groove or chip flute and one exchangeable cutting insert. At the tip of the shank a recess for accommodating the cutting insert is provided. The tool shank, on its circumference, has a limb with a bearing surface that is inclined relative to the tool axis and that corresponds to a likewise inclined bearing surface on a wing of the cutting insert. The inclination of the bearing surfaces produces an axial force that retains the cutting insert on the tool shank.

Abstract: A cutting drill includes a shank having a hole and formed to be gripped in a tool holder, and a drill body having a rod shape and locked into the hole of the shank. The shank has an axis around which the drill body rotates. The drill body has a cutting-edge portion forming a tip portion of the drill body and a neck portion having a diameter smaller than a diameter of the cutting-edge portion. The cutting-edge portion has a first cutting-edge portion and a second cutting-edge portion formed between the first cutting-edge portion and the neck portion. The first cutting-edge portion is contiguous to the second cutting-edge portion by a step portion such that the second cutting-edge portion has a diameter which is smaller than a diameter of the first cutting-edge portion.

Abstract: A rotatable drilling tool has cutting edges (on a face side) that merge inwardly into a chisel edge, with the chisel edge(s) running on the face side about a central region surrounding the tool axis, with the chisel edges forming, in the innermost region (or about a point thinning region), a residual chisel edge, with cutting edge corners being formed at the outer ends of the main cutting edges, with a straight connecting line that runs through two cutting edge corners of main cutting edges situated opposite one another in relation to the tool axis, or if an opposite main cutting edge is not present, through a cutting edge corner and the tool axis, with the chisel edge inner region running from the outer end of the residual chisel edge within a region with an angle of between ?15° and +15° in relation to a parallel to the connecting line.

Abstract: A loose top for drilling tools, including front and rear ends, a pair of envelope part surfaces concentric with a center axis, and two chip flutes countersunk in relation to the pair of envelope part surfaces between which two bars project radially from a central core, the front end including a cutting edge and at least one clearance surface positioned rotationally behind the cutting edge, the rear end forming an axial contact surface.

Abstract: The invention discloses a drilling toll having at least one chip groove for chip removal, having an insert seat which is formed at the end of the chip groove and serves as a holder for an indexable insert with at least one main cutting edge on the two narrow sides and with at least one secondary cutting edge on the two longitudinal sides of one face side wherein the indexable insert has two face sides facing away from one another and bears with its inactive face side on a holding surface of the insert seat, and a partial region of the inactive secondary cutting edge of its active face side lies in the insert seat at a distance from the adjoining side wall of the insert seat created by a slot, and wherein a guide lip which covers the slot protrudes out of the top side of the side wall in the direction of the inactive secondary cutting edge.

Abstract: A rotating tool includes a tool body, an outer cartridge, an inner cartridge and one or more setting plates. The tool body includes a pocket for the inner cartridge and a pocket for the outer cartridge. The outer cartridge has at least one cutting insert and a bolt through-hole extending toward a peripheral portion of the tool body. The outer cartridge is mounted on the pocket for the outer cartridge by means of a bolt. The setting plate is positioned to contact both the outer cartridge and the pocket for the outer cartridge. Screw holes for mounting the setting plate are formed on a side face of the outer cartridge adjacent to a rotating axis and through-holes are formed on the setting plate. This is so that the setting plate can be mounted on the side face of the outer cartridge by setting screws.

Abstract: A holder of the present invention has a first insert pocket and a second insert pocket at the tip end thereof. The first insert pocket is located closer to the central axis thereof than the second insert pocket. The axial rake of the first insert pocket is larger than the axial rake of the second insert pocket.

Abstract: A tool bit (1) ready for use consists of a sintered material. It has a longitudinal axis (3). At least one swarf chamber (4) spaced from the longitudinal axis (3) land extending along the longitudinal axis (3) is formed in the tool bit (1). The tool bit (1) has at least one cutting edge (8, 10), which is formed in the tool bit (1) by grinding the already sintered tool bit (1), adjoining the swarf chamber (4). According to the invention the swarf chamber (4) is ground only partly and is otherwise unground.

Abstract: The drill bit comprises a cutting blade formed at one end of a shank. The cutting blade has a pair of cutting shoulders that extend inwardly from the outer sides of the blade toward the bit axis. A tip having converging sides that create a point extends from the shoulders. The cutting edge of each shoulder is beveled with respect to the plane of the face of the blade. A flute is provided on the leading portion of each blade face adjacent the cutting edges. Each flute is a smooth curve that creates a substantially uninterrupted recess on each face of the blade that facilitates chip removal, increases the drill rate and lowers the power required to drill a hole. A non-stick coating may be applied to the blade to further facilitate chip removal.

Abstract: A drilling tool extends in a longitudinal direction and has a drill point and first and second major cutting edges, which extend approximately radially outward. The drill point is arranged eccentrically relative to a central axis, which is the same as the axis of rotation. The second major cutting edge is arranged by a cutting-height difference higher than the first major cutting edge. The first major cutting edge has a shorter radial edge length than the second major cutting edge. A method of utilizing the tool is also disclosed.

Abstract: A depth gauge for use with a drill bit includes a body configured to receive a drill bit, a retention mechanism coupled to the body and configured to removably couple the body to the drill bit, and a cap configured to be removably coupled to the body. The cap can be coupled to the body in one of a first position relative to the body where the cap contacts a workpiece surface to prevent the drill bit from entering the workpiece more than a first depth, and a second position relative to the body where the cap contacts the workpiece surface to prevent the drill bit from entering the workpiece more than a second depth that is different from the first depth.

Abstract: A rotating cutting tool (10, 110) includes a body (12, 112) with a longitudinal axis (14, 114) and at least one flute (16, 116) and one active part (18, 118). Each active part has a peripheral surface including: a radial cutting edge (20, 120) that is at a cutting distance (Rc) from the longitudinal axis, a clearance face (30, 130) that is at a final clearance distance (Rd) from the longitudinal axis, and a control face (40, 140) that is at a penetration control distance (Rp) from the longitudinal axis. These distances satisfy the relation: 0<?p<?d, with ?p=|Rc?Rp| and ?d=|Rc?Rd|.

Abstract: A small-diameter drill for deep hole drilling is provided which is capable of inhibiting the cutting chips from getting bitten and producing a straightness for a drilled hole, thus suitable for drilling a hole having a depth (L) which is 15 or more times the diameter (D) of a drilled hole. The small-diameter drill 1 has a diameter 2 which is 1 mm or less and a drill section 5 including cutting edge(s) 3 and flute(s) 4. The length 11 of the flute 4 is at least 5 times and at most 10 times the drill diameter 2. The diameter of the drill section 5, after being reduced in diameter from the cutting edge 3 toward the rear of the drill section 5, is expanded in diameter so that the outer diameter at the end of the flute 4 becomes at least 0.9 times and at most 0.98 times the drill diameter 2.

Abstract: A tool comprising a cutting section on which a multiplicity of blades or cutting edges and flutes are formed; a shank section, which forms a chucking section on a side which faces away from the cutting section, wherein a number of fluid channels which corresponds to the number of flutes is formed in the chucking section in such a manner that the fluid which emerges from axial discharge openings of the chucking section can be fed in a free jet along the shank into in each case one associated flute of the cutting section. Also, a method for supplying the blades of such a tool.

Abstract: The drill bit comprises a cutting blade formed at one end of a shank. The cutting blade has a pair of cutting shoulders that extend inwardly from the outer sides of the blade toward the bit axis. A tip having converging sides that create a point extends from the shoulders. The cutting edge of each shoulder is beveled with respect to the plane of the face of the blade. A flute is provided on the leading portion of each blade face adjacent the cutting edges. Each flute is a smooth curve that creates a substantially uninterrupted recess on each face of the blade that facilitates chip removal, increases the drill rate and lowers the power required to drill a hole. A non-stick coating may be applied to the blade to further facilitate chip removal.

Abstract: The present invention relates to a tool for machining workpieces, having a shank and a cutting part, wherein the cutting part has a cutting edge section that defines the nominal diameter of the tool, or an insert seat for a cutting insert, the seat having a cutting edge section that defines the nominal diameter of the tool, and wherein the tool has a rotational axis about which the tool rotates in the functionally mounted state.

Abstract: A tool comprising a cutting section, on which a multiplicity of blades or cutting edges and flutes are formed; a shank section, which forms a chucking section on a side which faces away from the cutting section, wherein a number of fluid channels which corresponds to the number of flutes is formed in the chucking section, which channels in each case have an axial discharge opening and lead along the shank to an associated flute of the cutting section. Also, a method for supplying the blades of such a tool with a pressurized fluid.

Abstract: A drill bit has a cylindrical drill head (1) having two essentially diametrically situated primary cutting edges (2) and chip channels (3) associated therewith. The outer surface (5) of the drill head is formed by curved sections (6) whose end faces (4) have teeth (8) which extend in the axial direction (A) and have cutting edges (7) and cutting faces (9). The cutting faces (9) run at an acute angle in the cutting direction (S) and are set back with respect to a radial line (L) passing through the cutting edge (7). The teeth are formed by crenellated elements (8) which with one of their respective side walls form a cutting face (9) of the cutting edges (7). The side walls (10) of the adjoining crenellated element (8) opposite from the cutting face (9) runs parallel to the cutting face (9).

Abstract: An improved cutting tool for drilling complex holes in a workpiece such as an automotive aluminum wheel, in which the tool has a shank and an integrally formed support section. A cutter insert secured in the support section. The cutter insert is formed with opposed flutes along the longitudinal axis of the tool. The tool is improved by reducing cutting forces and optimizing chip disposal, thereby cutting costs by reducing the load requirements for drilling holes, and this is accomplished by creating a positive rake angle at the flutes.

Abstract: A bit for removing a broken fastener comprises a tip from which extend two or more notches separated by traction or biting surfaces formed from two-sided frusto-conically-shaped regions. The surfaces are bounded on one side by a nonlinear cutting edge and on the other side by a non-cutting edge and are configured to cut into the fastener when the bit is rotated in a direction opposite to the fastener's direction of engagement. Specific embodiments include configurations where the cutting edges extend at different angles with respect to the bit axis, where the biting surfaces comprise a plurality of serrations, and where the cutting edges are separated by flutes which spiral along a longitudinally extending periphery of the bit.

Abstract: The invention relates to a drilling tool, in particular for metallic materials, having a clamping shaft and an essentially cylindrical drill body, between whose face side and the clamping shaft at least one groove-shaped chip space extends which is bordered by the side walls, of which one side wall on the face side of the drill body bears a cutting element. The side wall which bears the cutting element has a web which is drawn up from the side wall in the peripheral direction and which extends in the longitudinal direction of the drill.

Abstract: Embodiments of the invention comprise an auger bit for use with a power drill including an elongated member including a first end and an opposing second end, a helical surface having a central axis, where the helical surface defines at least one flute, a head portion integrally formed with the first end of the elongated member and including a primary cutting edge adapted to engage and remove material from a workpiece and a secondary cutting edge adapted to engage and remove additional material from the workpiece, a threaded tip integrally formed with the head portion and a shank integrally formed with the second end of the elongated member and adapted to engage the drill.

Abstract: The drill bit comprises a cutting blade formed at one end of a shank. The cutting blade has a pair of cutting shoulders that extend inwardly from the outer sides of the blade toward the bit axis. A tip having converging sides that create a point extends from the shoulders. The cutting edge of each shoulder is beveled with respect to the plane of the face of the blade. A flute is provided on the leading portion of each blade face adjacent the cutting edges. Each flute is a smooth curve that creates a substantially uninterrupted recess on each face of the blade that facilitates chip removal, increases the drill rate and lowers the power required to drill a hole. A non-stick coating may be applied to the blade to further facilitate chip removal.

Abstract: A tool for chip removing machining, including a basic body having a connecting surface included in an insert seat, and an indexable cutting insert mounted in the basic body and having a connecting surface in mechanical engagement with the connecting surface of the basic body, and fixed by a tightening element. The connecting surface of the basic body includes a solitary, polygonal elevation that protrudes from a bottom surrounding the elevation from all sides. The elevation includes two external side support surfaces orientated at an angle to each other. The connecting surface of the cutting insert includes a solitary depression that is wider and deeper than the elevation.

Abstract: A circular truncated cone-shaped cutting section (3) of a chamfering tool (1) is formed with a first blade section (31) which is tilted so that a chip is discharged to a side of a shank section (2), and a second blade section (32) which is tilted so that the chirp is discharged to a direction opposite to the side of the shank section (2) in a peripheral direction with a gap. The chamfering tool (1) is rotated, and the first blade section (31) and the second blade section (32) are alternately brought into contact with an edge of an object to be worked so that the edge is chamfered. As a result, occurrence of a secondary burr on the edge is suppressed.

Abstract: A gun-drill comprises a cutting-head detachably secured to a shank, having a common longitudinal axis and comprising mating peripheral surfaces. A shank coupling portion comprises a forwardly tapering shank fixation surface is formed at a front end of the shank, and a cutting-head coupling portion comprising a forwardly tapering cutting-head fixation surface is formed at a rear end of the cutting-head. Both the shank and the cutting-head coupling portion extend over a peripheral coupling angle ? of more than 180°. The shank and the cutting-head are assembled by positioning the cutting-head leading face in front of the shank trailing face, slidably inserting the cutting-head coupling portion into the shank coupling portion laterally to the axis of rotation A and rotating the cutting-head relative to the shank in a direction opposed to the direction of rotation R so that the cutting-head coupling portion and the shank coupling portion interlock co-axially.

Abstract: In one aspect of the invention a drill bit comprises an axis of rotation a body and a working face. The body comprises a fluid passageway with a first seat and houses a jack element substantially coaxial with the axis. A stop element is disposed within the passageway and has a first near-sealing surface. The jack element has a shaft intermediate an indenting end and a valve portion. The valve portion has a second near-sealing surface disposed adjacent the first near-sealing surface and a second seat disposed adjacent the first seat. As a formation strongly resists the jack element, the distance between the sealing surfaces narrows. This causes an increase in fluid pressure within the passageway and forces the indenting end down into the formation. This movement of the jack element relieves the pressure build up such that the formation pushes the jack element back, thereby oscillating the jack element.

Abstract: An edge-carrying drill body intended for deep hole drilling, is rotatable around a central geometric axis and comprises a through-channel arranged for internal chip evacuation. The channel mouths in front and rear ends of the drill body. A front channel mouth is bridged-over by a bridge on which a plurality of cutting edges are formed, which edges are made integrally with the rest of the bridge. The front mouth includes inlets disposed in front of respective cutting edges with reference to the direction of rotation of the body.