Abstract: The present invention provides a cutting tool assembly having a tool shank with an elongated hole extending axially through the tool shank. An elongated support bar having threaded bore at its forward end is retained in the elongated hole. A cutting head having a forward cutting portion and a rear threaded portion is retained in the support bar with its rear threaded portion threadingly engaged with the threaded bore in the forward end of the support bar.

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 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: 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: A tool for cutting machining includes a holder, a cutting head and a threaded fastener for fastening the cutting head to the holder. The cutting head is formed of injection molded cemented carbide and includes at least one cutting edge. The holder has a front surface and the cutting head has a support surface provided to releasably abut the front surface substantially in a radial plane. A central blind hole is provided in the support surface. An insert formed of a material softer than injection molded cemented carbide is secured in the blind hole. The insert includes a thread cooperating with a thread of the fastener for pulling the cutting head toward the holder in response to rotation of the fastener. By further tightening the fastener after the support surface abuts the front surface of the holder, the contact between the thread of the fastener and the thread of the insert forces the insert radially outwardly against a wall of the blind bore.

Abstract: A spotting drill and milling cutter (10) having a shank (30) and a pocket (50) for receiving an insert (52). The cutter is capable of forming a spotting hole (12) having a concentric circular cavity (16) at the bottom of the spotting hole. Insert (52) includes a primary cutting edge (54), a secondary cutting edge (64) and a tertiary edge (68) having a cutting portion (68a). The primary cutting edge terminates at a point (56) which is radially offset about 0.001″ to 0.100″ with respect to rotation axis (36) of the cutter. Primary radial relief surface (76) associated with the primary cutting edge and secondary radial relief surface (78) associated with the secondary cutting edge are provided to reduce back dragging relative to the primary and secondary cutting edges.

Abstract: A twist drill includes a shank which defines a longitudinal center axis and has a helical, chip-transporting flute formed therein. A cutting insert is arranged at a front end of the flute. The insert includes a body forming a cutting edge and a flank surface arrangement situated behind the cutting edge. The flank surface arrangement includes first and second flank surfaces extending at respective first and second acute angles relative to a reference plane which contains the center axis. The sizes of the first and second acute angles are different from one another. In one embodiment, each of the first and second flank surfaces intersects the cutting edge. In a second embodiment, only the second flank surface intersects the cutting edge, with the first flank surface extending from a rear end of the second flank surface.

Abstract: A cutting insert for a borer or reamer comprising a flat blade having a front face with at least one cutting edge, the front face having at least one depression, or dimple, having clamping faces therein which are frustoconical and which in use engage a clamping screw whereby the blade is held in the reamer. The clamping faces extend in a direction parallel to the cutting edge, and the depth of the depression changing continuously in longitudinal cross-section.

Abstract: Proposed is a drilling tool for drilling in solid material, having a base body (1) containing chip flutes (5, 5a) and at least two interchangeable inserts (3, 3a) at the face of the base body (1). The inserts are arranged on the base body at different radial distances such that their working ranges partially overlap. The blades (12) of the inserts (3, 3a) are formed by two cutting edges (8, 9) which together form an obtuse angle, that is the point angle (11). The face (13) of the blades (12) has parallel profile ribs (14, 14a) which act as runners and which in the region of the cutting edges (8, 9), aligned in the direction of chip removal, extend radially inwards over a curved course relative to their installed position, toward a flank region (17) of the insert (3, 3a) near the drilling tool axis (7).

Abstract: A milling cutter is provided including a tool holder and a cutting tool insert. The tool holder includes a mounting end portion and a cutting end portion. The cutting end portion includes a slot defined by first and second diagonal surfaces provided in an end of the cutting end portion. The first and second diagonal surfaces form a substantially V-shaped pocket for receiving the cutting tool insert. The cutting tool insert includes a substantially flat body member having a V-shaped seat portion and a cutting portion, the cutting portion includes a first cutting lobe and a second cutting lobe. A hole is provided which passes through the body member. A screw hole passes through the cutting end portion of the milling cutter which intersects the U-shaped pocket. A threaded portion of the screw hole is offset from a clearance portion of the screw hole to positively seat the V-shaped seat portion of the insert in the V-shaped pocket of the tool holder.

Abstract: A drilling tool is proposed comprising a shaft which has both a chuck shaft suitable for fitting in machine tools and a drill-holding shaft, known per se, with chuck grooves and (optionally) coolant ducts. A replaceable drill bit (1) is fitted in a positive fit and detachably on the shaft. The drill bit can consist of a homogenous material and has cutting edges (2) inclined radially outwards and backwards; these cutting edges can be formed in one piece from the drill bit material or are composed of blades mounted in the central region and made from the drill bit material and complementary blades orignating from a cutter plate screwed onto the drill bit. The invention proposes that the cutting edges (2) should be aligned symmetrically about the drill bit axis and the cutting edges should be in cutting engagement over the entire radius of the bore to be drilled.

Abstract: A drilling tool comprises a drill tip, a chip removal part which axially adjoins the drill tip, and a drill shank which is positioned at the end of the chip removal part. Two chip flutes extend in a helical manner over the chip removal part starting at the main cutting edges of the drill tip. The drilling tool is separated into two parts in the region of the chip removal part and consists of a base body which is connected to the drill shank as one part and an exchangeable tip made of a harder material which is connected to the drill tip as another part. The exchangeable tip is connectable to the base body in a form-fitting and/or frictional-fitting manner at an axial separation point.

Abstract: In a cutting head with exchangeable hard metal cutting blades for woodworking, wherein the cutting head includes a body with a center hub portion and arms extending radially therefrom and having support surfaces with cutting blades mounted thereon, the support surfaces and the cutting blades have cooperating stop means for axially and radially positioning the cutting blades on the support surfaces and clamping means are provided for firmly engaging the cutting blades with the support surfaces while they are held in contact with the stop means, and a cutting blade is mounted on each arm of the cutting head.

Abstract: Proposed is a drilling tool for drilling in solid material, having a base body (1) containing chip flutes (5, 5a) and at least two interchangeable inserts (3, 3a) at the face of the base body (1). The inserts are arranged on the base body at different radial distances such that their working ranges partially overlap. The blades (12) of the inserts (3, 3a) are formed by two cutting edges (8, 9) which together form an obtuse angle, that is the point angle (11). The face (13) of the blades (12) has parallel profile ribs (14, 14a) which act as runners and which in the region of the cutting edges (8, 9), aligned in the direction of chip removal, extend radially inwards over a curved course relative to their installed position, toward a flank region (17) of the insert (3, 3a) near the drilling tool axis (7).

Abstract: A rotatable machine tool such as a precision boring tool has a head (2) that is detachably mounted on a shank type driving element (3). The head carries a removable cutting tip (9) and includes a bearing point (8) that wedgingly seats within a transverse slideway (7) in driving element (3). A slide (11), which is mounted in through bore (20) in head (2), has a male member (10) attached thereto which passes through a slot (24) extending between the bore (20) and an end face (19) of the head (2). Male member (10) is received within a bore (12) in driving element (3). A clamping screw (13) in drive element (3) interacts with male member (10) to cam it inwardly thereby clamping head (2) in position on drive element (3). The head (2) is transversely adjustable within slideway (7) by loosening screw (13) and adjusting opposed screws (32, 33) in head (2) which act on male member (10).

Abstract: A tool for cutting machining comprises a tool body, a cutting member and a fastener for fastening the cutting member to the tool body. The tool body has a shank, a central bore formed therethrough, and a front surface having grooves formed therein. The cutting member includes a cemented carbide body having a cutting edge formed in a front surface thereof, and a rear supporting surface. The supporting surface includes ridges received in the grooves, and a rearwardly open blind hole. The fastener extends through the central bore and is threadedly connected to the blind threadedly connected to the blind bore for pulling the cutting member against the tool body.

Abstract: A drill including a cutter member and a shank which are formed separately from each other and fixed to each other for rotation as a unit, wherein the shank has an engaging groove formed in a distal end face thereof such that the engaging groove extends in an axial direction of the shank and is aligned with a center of the distal end face, and the cutter member consists of a rectangular plate including a proximal end portion fixed to the shank by engagement thereof with the engaging groove, and a distal end portion which is remote from the shank and which has at least one cutting edge.

Abstract: A drill with a drill point part that contains the drill cutter and is made of a solid hard material. The drill point part is replacably attached to the end face of a drill shaft. The drill shaft is penetrated by a shaft groove which extends in an axial direction of the shaft to accomodate the drill point part and can center the drill point part in the groove region. The drill shaft has grooves on its periphery which run in the axial direction and extend into the region of the shaft groove and continue into the region of the drill point part. The drill point part can be clamped on its side faces corresponding to and opposite the groove flanks in a force-locking manner by an insertion-clamping fit in the shaft groove.

Abstract: An arbor for a hole saw includes a shaft and a plurality of pins having either bearing surfaces, drive portions or both for engaging the hole saw. The arbor further includes a fixed position flange and a locking plate located above the flange, to which the pins are connected. The saw is mounted to the arbor and has a cylindrical body portion having a closed end defined by a drive plate and an opposite end defining a cutting edge for performing sawing operations on a work piece. The drive plate includes apertures for receiving the drive portions of the pins which pass through holes in the flange. When assembled the drive ends of the pins extend through the holes in the flange and into the mating drive plate apertures such that the bearing surfaces on the pins engage and support the drive plate of the hole saw.

Abstract: A metal cutting tool includes a tool body rotatable about a center axis and a tool tip mounted on a front surface of said tool body for performing a cutting operation. A draw bar mounted axially in the tool body draws a rear surface of the tool tip toward the front surface of the tool body. Those front and rear surfaces include radial projections and radial recesses receiving the projections. The projections are wedgingly connected in the recesses to transmit all axial and rotational forces between the tool body and tool tip.

Abstract: A throwaway ball end mill comprising an end mill body and a tip pressed by a clamp screw onto a cutout formed at the forward end of the end mill body. The cutout is formed in a longitudinal direction with respect to the end mill body, and a pair of lateral regions forked by the cutout have opposite flat surfaces, the lateral regions have clamp holes formed in a direction making a right angle with the cutout, one clamp hole has a conical surface extending toward the periphery of the corresponding lateral region, and the other clamp hole has a female thread formed therein,the centerline of the conical surface is deviated from that of the clamp holes toward the base end of the end mill body. When the clamp screw is tightened with the tip inserted in the cutout, the tip is pressed against the end of the cutout accordingly, and at the same time one lateral region is bent toward the other lateral region.

Abstract: For the purpose of rigid connection of the cutter holder (9) to the tool carrier (5), the tool carrier (5) has a driving key (11) on its end side, which driving key is inserted into a corresponding transverse groove (13). The driving key (11) has a specified excess size compared to the transverse groove (13), such that when a setscrew (10) is tightened the tool carrier (5) and the cutter holder (9) are elastically deformed. Laterally next to the transverse groove (13) the surface of the cutter holder (9) is supported on the tool carrier (5).

Abstract: A boring bar includes an insert pocket formed on the back side of a relief in the working end of the bar, for the removable installation of a cutting insert therein. The insert pocket may be formed to provide a positive rake angle for the insert installed therein, relative to the axis of the bar, and further may include a positive angle relative to the radius of the bar as well. The force imparted to the insert as the bar is forced against the workpiece, tends to force the insert upwardly and inwardly into the pocket of the bar, thus assisting in holding and securing the insert to the bar. The bar is also thicker at the upper portion of the insert pocket than at the lower portion of the pocket, thus providing additional strength and stiffness to the bar in this critical area to reduce the possibility of chatter and breakage of the bar. Either the tool moves and the workpiece is stationary, or the workpiece moves and the tool is stationary.

Abstract: A method and machine for repairing overhead cam engine cylinder heads and the like. The method includes the steps of removing the caps from the bases of the bearing towers or housings, removing material from the legs of the caps to reduce their height, replacing the caps on the bases, and boring the resulting bearings to produce bearings of the proper diameter. The machine includes a device for machining a bearing cap and a device for boring the bearings. The device for boring the bearings has a boring bar that is supported only at opposite ends of the cylinder head. The bar does not sag or chatter because it is made of an extremely hard and dense material such as a dense tungsten alloy or a ceramic-coated metal.

Abstract: A drill including a substantially columnar tool body having an axis. The tool body includes a pair of chip ejection grooves formed in an outer peripheral surface thereof. The tool body further includes, in a distal end portion thereof, a pair of cutting edges provided at respective distal ends of the pair of chip ejection grooves and a recess communicating with the pair of chip ejection grooves. The pair of cutting edges have radially inner ends located in positions slightly offset from the axis radially outward, and the recess extends along the axis while passing a gap between the radially inner ends of the pair of cutting edges, and has a bottom surface facing a distal end of the tool body. The bottom surface of the recess includes one slope and another slope.

Abstract: A milling cutter is provided including a tool holder and a cutting tool insert. The tool holder includes a mounting end portion and a cutting end portion. The cutting end portion includes a slot defined by first and second diagonal surfaces provided in an end of the cutting end portion. The first and second diagonal surfaces form a substantially V-shaped pocket for receiving the cutting tool insert. The cutting tool insert includes a substantially flat body member having a first side having a cutting surface on one edge thereof and a second identical side having a cutting surface on one edge thereof. A hole is provided through the body member from the first side to the second side. First and second surfaces are provided adjacent and substantially perpendicular to the first and second sides. The first and second surfaces define a V-shaped seat portion for seating the cutting tool insert in the V-shaped pocket of the tool holder.

Abstract: A valve seat tool assembly has a body adapted for selective rotation about a longitudinal axis. The body includes recesses that receive removable cartridges therein. Preferably, the cartridges have a cylindrical shank received in the recesses and carry cutting inserts on each cartridge. The cartridge and cutting inserts may be mounted in any of three desired manners, all of which advantageously permit axial adjustment of the cartridge relative to the body.

Abstract: A speed-increasing spindle device in an assembly structure in a separable form of device main body and shank, capable of using a coupling bolt of large diameter, high in rigidity, and sufficient in strength. The head of the coupling bolt is rotatably engaged in a bolt head engaging part provided at one side of the device main body and shank, while the threaded part of the coupling bolt is engaged with a screw hole provided at the other side of the device main body and shank, and the engaging part for rotary operation tool provided on the outer end plane in the axial direction of the coupling bolt confronts outside through the insertion hole of the shank. The bolt head engaging part has a bolt head accommodating space larger than the maximum hole diameter permitted in the shank in terms of strength, and therefore the shaft diameter of the coupling bolt may be set, at least, as large as the maximum hole diameter of the shank.

Abstract: A Forstner bit including a cutter having radial major cutting edges, circumferential cutting edges and a shank adapted to be clamped in a chuck. The cutter is threadably attached to the shank by a rear stem of the cutter being accommodated in a threaded hole provided in the shank. The cutter is formed as a monolithic casting fashioned of a precision-casting steel alloy, with the cutter being subjected to additional grinding only along the major cutting edges and the circumferential cutting edges.

Abstract: A tungsten carbide boring bar has a mechanism for securing the cutter insert in a passage in the boring bar. The boring bar has a transverse bore through the body of the tool. A steel plug is received in the bore closely adjacent the position of the insert. The plug has a central threaded passage. A retainer is threadably received in the plug and has an inner end seated in a notch in the shank of the insert to retain the tool in position, and an outer end adapted to receive a turning tool.

Abstract: A drill including a bit having an extension received in and axially extending groove formed in the end face of the drill base body, a side cutting edge projecting beyond the base body circumference, and two active end cutting edges projecting beyond the end face of the base body, with the drill further including clamping elements for securing the bit extension in the base body groove with a possibility of radial adjustment.

Abstract: A drill for drilling in metal with improved performance in the smaller diameter range. The drill comprises a drill shaft, the front end of which is provided with radially outer and radially inner inserts, each insert having elongated rhomboidic shape, in which each of the short sides is broken at its middle to form a V-shape having an internal obtuse angle. The inserts are arranged such that the longitudinal axis of the radially outer insert is inclined at an angle from the longitudinal axis that is different from the angle of inclination between the longitudinal axis of the radially inner insert and the longitudinal axis of the drill.

Abstract: A cutting tool having a cutting plate with at least one blade and a central axial hole through which a head screw can be used to connect the cutting plate to a holder having an axial bore through its center for receiving the screw and a recess around the bore for receiving a complimentary projection located around the central hole of the cutting plate which is longer than the recess is deep. Alternate embodiments are provided in which the projection is located on the holder and the recess in the face of the cutting plate. In all embodiments, the recess and projection have contacting surfaces which substantially eliminate axial forces on the head screw.

Abstract: A drill includes a substantially cylindrical holder (10) with a longitudinal axis (X) and a transverse axis (Y) perpendicular thereto, a drill tip (12) in which there is a groove (14) running along the transverse axis (Y) with a groove bottom (16) and groove sides (18',18"), and a cutting insert fitted in the groove having two main cuts (26',26") with forwardly adjacent cutting surfaces (32',32") and two rear surfaces (30',30") opposite a cutting surface on the other side of the transverse axis (Y). The holder has two bores (20',20") in a radial plane (R) of the drill, each of which is in the region of a rear surface (30',30") of the insert (25) and opens into a groove side (18',18"). The longitudinal axes (24',24") of the drillings (20',20") run at an acute angle to the groove side (18',18") and the adjacent rear surface (30',30") of the insert (25).

Abstract: A cutting insert having a cutting head and a coupling shank integral at one end thereof with the cutting head and including a screw threaded portion. The cutting insert is formed by a powder metallurgy process of compacting and sintering and the screw threaded portion is constituted by a substantially cylindrical body having a pair of diametrically opposed, longitudinally truncated planar portions interposed between substantially curved cylindrical portions having arcuate surfaces on which there are formed a non-continuous screw thread, the arcuate surfaces extending between 50 to 85% of the total peripheral extent of the cylindrical body of which they form part. There is also disclosed a powder metallurgy process for manufacturing the cutting insert.

Abstract: A cutting tool particularly adapted for machining brittle plastics in which the cutting head has its cutting edges in the first and fourth quadrants of the x-y axes and contained in a common plane on opposite sides of the axis of tool rotation. The cutting edges are on two planar inserts, which can be either integral or separate elements, which meet at the common plane and each of which is relieved or cut away in the opposite quadrant from its own cutting edge to expose the cutting edges of the other. The walls defining the reliefs have 2 or more non-aligned sections forming different angles with the axis of rotation with the steepest angle beginning at the axis and preferably inwardly of the tip of the tool and, overall, exposing not less than a full quadrant of the cutting edge of the other insert while providing cavities and contours which control the movement of the chips and the flow of coolant fluids.

Abstract: A cutting insert having a cutting head and a coupling shank integral at one end thereof with the cutting head and including a screw threaded portion. The cutting insert is formed by a powder metallurgy process of compacting and sintering and the screw threaded portion is constituted by a substantially cylindrical body having a pair of diametrically opposed, longitudinally truncated planar portions interposed between substantially curved cylindrical portions having arcuate surfaces on which there are formed a non-continuous screw thread, the arcuate surfaces extending between 50 to 85% of the total peripheral extent of the cylindrical body of which they form part. There is also disclosed a powder metallurgy process for manufacturing the cutting insert.

Abstract: A thread cutting tool which can be configured to cut threads in a variety of bore sizes using universal thread cutting chasers mounted in select radial extension such as by using variable length tool blocks which are themselves interfit within retaining slots in the head portion of the tool, or by providing alternate radial position notches an the head portion for mounting the cutting chasers. By using variable tool blocks mounted to the head portion of the tool, universal thread cutting chasers having a preselected thread pitch can be utilized for multiple bore sizes, thus saving the expense of providing chasers or head portions corresponding to each bore size. Alternately, by providing alternate radial position notches in the head portion for mounting the cutting chasers, a single tool can be used for different bore sizes, such as for undertaking a start thread cut in a bore and then undertaking a finish thread cut in the pre-cut bore using an alternate radial position for the chasers.

Abstract: A Drilling tool for metallic materials comprises a holder (1) having an axial clamping slot in which a plate-shaped drilling blade (2) is inserted and clamped against a limb (8) of the clamping slot by means of a threaded pin (3), which is provided with a head (21) and which engages in a bore (15) in the drilling blade (2) and in a bore (12) in said limb (8). The center axis (13) of the limb bore (12) is offset relative to the center axis (24) of the drilling blade bore (15). The mutually facing circumferential edges of the head (21) of the threaded pin and the bore (15) of the drilling blade is bevelled. A centering pin (11) is inserted in the holder (1) and engages in a centering slot (18) in that side (17) of the drilling blade (2), which is contacting the base surface (9) of the clamping slot (4) to center the drilling blade (2) with respect to the rotational axis (6) of the holder (1).

Abstract: This Improved Rotary End Cutting Tool is a completely new concept in twist-drill theory, design, and method of construction. Which will revolutionize the rotary end cutting tool systems as presently known today; especially in larger drill (30) diameters. The new concept of an incurvate cutting-edge (38), purposely orchestrated and offset volumetric grooves (41) combined with a tapered residual core-area (50) in the forward conical forward-end, along with all other renovative improvements. Has virtually resolved drill-chatter, rapid dulling, poor centering, penetration, and even breakage; naming just a few from a list of problems inhabiting currently marketed twist-drills (30). With the overall combined improvements, being to extensive to list herein, having afforded a uniquely simple insert cutting-unit (47) displaying a fixed and removable version capable of equally performing as well as its one-piece counterpart twist-drill (30).

Abstract: A drilling tool has a drilling crown (12) removably arranged on a shank (10) at its front face, provided with two complementary regions that are mutually separated by chip channels (20) and that have partially circumferential surfaces (48). The drilling tool also has at least two cutting plates (14, 14', 16, 16') secured to the regions of the drilling crown and spaced apart by an angle of 180.degree., as well as a centering drill (26) centrally arranged in the drilling crown in the axial direction that projects over the front face of the latter. The cutting edge (18) of the outermost cutting plate (14) in the radial direction radially projects over the circumferential surfaces (48) of the drilling crown (18), whereas the working area of the innermost cutting plate radially approaches or overlaps the working area of the centering drill (26).

Abstract: A new and improved interchangeable head boring or driving apparatus includes a first head-receiving member which includes a first polygonal-shaped receiving well which is in alignment with a longitudinal axis of the head-receiving member. A plurality of respective interchangeable head assemblies include respective head elements and respective projections which project from the head elements. The respective projections include a first polygonal shape complementary to the first polygonal-shaped receiving well. The respective projections project from the head elements, such that, when the respective projections are inserted into the first polygonal-shaped receiving well, the respective projections and the first polygonal-shaped receiving well arc coaxial along the longitudinal axis. A locking assembly locks the respective projections into the first polygonal-shaped receiving well of the head-receiving member.

Abstract: The present invention relates to a cutting tool, especially the cutting tool having a head segment releasably attached to a shank segment.

Abstract: A drill with indexable inserts has one center insert (11) and one peripheral insert (12), said center insert having a symmetric drill point (25) on the drill axis (10) with a transverse edge which is continuous with one short edge (27) and one long edge (21,23) and a screw hole offset from the symmetry axis of the drill point (25) towards the side of the long edge (21,23).

Abstract: A drill has a pair of cutting edges (4) which are arranged at positions that are substantially uniformly circumferentially spaced about its rotation axis. Each of the cutting edges (4) has a first linear cutting region (4a) and a second linear cutting region (4b) which are aligned with each other on the same straight line, and a curved cutting region (4c) which is located between the first and second linear cutting regions (4a, 4b). The curved cutting region (4c) has a third linear cutting region (4e, 4f) which extends in a direction intersecting with the second linear cutting region (4b) at a prescribed angle. With this structure, it is possible to prevent chip loading etc. which may be caused during perforation drilling operations. In a throw-away tipped drill, a notch (118a) is formed in a received portion of an insert (110) which is mounted on a shank (130). A holding portion (131a, 131b, 133a, 133b) of the shank (130) corresponding to the notch (118a) is provided with a through screw hole (138).

Abstract: The present invention relates to a cutting tool, especially the cutting tool having a head segment releasably attached to a shank segment.

Abstract: An elongated grooving or threading tool has a cutting section and a rearward cemented carbide section which are held together in axial alignment by a drawbolt which extends through an axially aligned bore in the cutting section and engages the respective sections to hold the connection under compression.

Abstract: A spot drilling and centering drill including a body having a cylindrical head portion and a replaceable indexable insert mounted in the head portion. A V-angled slot is formed directly in the head portion. The insert has two V-angled cutting surfaces with a drill point, each cutting surface fitting within the V-angled slot to locate the drill points on the centerline of rotation of the drill.

Abstract: A drill bit includes an elongated shaft with a threaded male end and a cutting head with an axial through-bore having female threads to receive the male end of said shaft in threaded engagement, and there is a bearing surface area between the shaft and the cutting head above the threaded portion which provides for proper alignment and reduced stresses.