Having Peripherally Spaced Cutting Edges Patents (Class 408/227)
  • Patent number: 5217332
    Abstract: A high performance drill bit is presented for precision drilling of holes in hard-to-drill materials, such as a carbon fiber reinforced plastic material. The drill is a gun drill type having a pair of flat flutes and a pair of air holes for delivering coolant and/or lubricant. The main feature of the drill is the provision of two pairs of cutting edges formed on the intersecting ridges formed at the leading sides of the flank surfaces with the flute surfaces. At the tip of the drill bit, a pair of primary cutting edges, having a point angle .alpha., is disposed. It is followed by another pair of secondary cutting edges, having a point angle .beta., where .alpha.>.beta.. Physically, this means that the secondary cutting edges are inclined more toward the drill axis than the primary cutting edges. The secondary cutting edge is followed further by another flank surfaces which are even more inclined toward the drill axis.
    Type: Grant
    Filed: May 7, 1992
    Date of Patent: June 8, 1993
    Assignees: Mitsubishi Materials Corporation, Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Kazuo Takasaki, Yasunori Murakami, Hiroshi Kasutani, Koji Hashimoto, Yutaka Adachi
  • Patent number: 5203653
    Abstract: A reamer for shaping a socket, such as a hip socket, comprising a cutter head located at one end of a rotatably driven shaft and having a hemispherical portion with a hemispherical exterior surface, the hemispherical portion containing a closed hollow chamber, and helical openings, such as slots, in said hemispherical portion connecting between the exterior surface and the chamber, the trailing portion of each of the openings having a cutting edge raised slightly above the hemispherical surface to move material from the socket into the chamber during rotation of the cutter head, and an attachment element for connecting and disconnecting the cutter head and the drive shaft.
    Type: Grant
    Filed: December 30, 1991
    Date of Patent: April 20, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventor: John W. Kudla
  • Patent number: 5181810
    Abstract: A deburring tool has at least one cutting blade mounted in a guide recess of the tool for deburring and chamfering bores. The blade is of rectangular shape with forward, non-cutting end face and longitudinal side faces extending rearwardly from the end face. At least one side face has a non-cutting glide surface extending rearwardly from the end face at a first angle, and a cutting edge extending rearwardly from the glide surface at a second, different angle.
    Type: Grant
    Filed: June 11, 1991
    Date of Patent: January 26, 1993
    Inventor: Heinrich Heule
  • Patent number: 5149231
    Abstract: A counterbore for enlarging an existing hole in the presence of a wire having an end extending through the hole. The counterbore includes a twist drill bit of a size of the enlarged hole to be drilled, a shank at the rear end of the bit for engagement with a drill chuck, and a pilot shank extending from the cutting end of said bit. A swivel is mounted at the leading end of the pilot for engagement with the wire during counterbore drilling. The swivel and pilot guides the wire into the hole without twisting during drilling of the counterbore and extracts the wire from the counterbore as the twist drill bit and pilot shank is withdrawn.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: September 22, 1992
    Inventor: Roy E. Bowling
  • Patent number: 5094571
    Abstract: A drill produced from a substantially rod-like blank containing high speed steel has at one end thereof a pointed tip which is intended to penetrate the material to be drilled. The drill is preferably a helical drill having edge parts which extend essentially from the outer part of the drill tip to the periphery of the drill cross-section, and further includes a radially open groove which extends helically along the drill, for the purpose of removing chippings from the drill.The drill is particularly characterized in that the blank, and therewith also the drill, in cross-section includes a central steel part, which is intended to exhibit high compressive stength, and which therewith forms the outer part of the drill tip, and a concentrical outer layer of high-speed steel which is intended to exhibit high thermal stability and which is applied with the aid of a casting technique.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: March 10, 1992
    Inventor: Sven Ekerot
  • Patent number: 5078554
    Abstract: A drill, which is excellent in sharpness and strength, capable of preventing burrs at an exit of a machined bore and of suppressing an excessive enlargement of the machined bore size, and is low in manufacturing costs, and easy te re-grind.A rake face (30) is provided to improve sharpness of a single chisel edge (3) formed between the tip of the drill and a first main cutting edge (1), and a non-chisel-edge-forming portion (B.sub.1 OB.sub.2) is provided between the drill tip end and a second main cutting edge (2) to improve strength of the drill.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: January 7, 1992
    Inventor: Masao Kubota
  • Patent number: 5071294
    Abstract: A burnishing drill includes a cylindrical drill body connected at its forward end integrally with a shank. The forward end of the drill body includes a first pair of cutting edges inclined radially and rearwardly from the forwardmost central end of the drill body toward the shank at a first cutting angle. A second pair of cutting edges formed of diamond chips are disposed in a plane intersecting the plane in which the first pair of cutting edges are located. The second pair of cutting edges are inclined radially and rearwardly from a position inside a circle including the maximum external margins of the first pair of cutting edges toward the shank at a second cutting angle.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: December 10, 1991
    Assignees: Aisan Kogyo Kabushiki Kaisha, Fuji Seiko Limited
    Inventors: Yasuhiro Suzuki, Tuguo Yoshikawa, Kazuhiro Shibata, Akio Fukui, Kiyotaka Shiga
  • Patent number: 5054972
    Abstract: A rotatable arbor-type tool for use in a portable power drill is provide for sharpening the ends of metal studs and particularly snowmobile tread studs or spikes. The tool has a cylindrical head with a tapered central opening axially aligned with the axis of rotation of the head. Radial grooves extend from the central opening through the wall of the head to the outer surface thereof. One wall of each groove constitutes an abutment wall against which a preferably triangular cutting blade having a thickness substantially less than the groove width is positioned. The cutting blade is forceably held against the abutment wall by a set screw extending against the cutting blade from the opposite wall leaving an opening extending along the groove past the cutting tool sufficiently wide to provide an exit from the central opening for chips cut from the end of the stud by the cutting edges of the cutting tool. The abutment wall is that wall which faces the direction of rotation of said head.
    Type: Grant
    Filed: May 15, 1990
    Date of Patent: October 8, 1991
    Inventor: Kevin G. Cooney
  • Patent number: 5022801
    Abstract: The present invention is directed to a twist drill which is coated with a layer of CVD diamond and which has slots in its head which are filled with CVD diamond. The invention twist drill is made by forming slots in the head of the twist drill and then subjecting the slotted twist drill to a CVD diamond deposition process for coating said twist drill with a layer of CVD diamond and for filling said slots with CVD diamond. The performance of CVD diamond-coated twist drills does not depend on retaining the diamond film over most of the areas of the drill; but, rather, drill performance is dependent upon retaining a layer of diamond on the cutting edge of the drill. The diamond-filled slots in the head of the twist drill function as wear stops and additional cutting edges as the surrounding drill material is worn away during use.
    Type: Grant
    Filed: July 18, 1990
    Date of Patent: June 11, 1991
    Assignee: The General Electric Company
    Inventors: Thomas R. Anthony, James F. Fleischer
  • Patent number: 5004384
    Abstract: A drill having a shank formed with helical or straight flutes for discharging chips therethrough and a pair of cutting edges formed at one end of the shank and extending continuously from the center of rotation of the drill to the periphery thereof. Each of the flutes is defined by a wall which is positioned rearward with respect to the direction of rotation of the drill and against which a flat plate portion of the chip formed by the portion of the cutting edge on the peripheral side is to be pressed, and by a wall positioned forward with respect to the direction for a side edge portion of the chip to come into contact with. The forward wall is inclined with respect to the rearward wall so as to prevent the chip from curling in its entirety. The drill is given improved rigidity and adapted to discharge chips as broken into fragments of suitable length.
    Type: Grant
    Filed: March 6, 1989
    Date of Patent: April 2, 1991
    Inventor: Toshiaki Hosoi
  • Patent number: 4984944
    Abstract: A drill bit blade for masonry and rock drills incudes first and second lateral side surfaces, first and second flank side surfaces, and converging first and second tip face surfaces. A first lateral cutting edge is defined by the intersection of the first tip face surface with the first lateral side surface, and a first lateral trailing edge is defined by the intersection of the first tip face surface with the second lateral side surface. A first lateral cutting edge is defined by the intersection of the first tip face surface with the second lateral side surface, and a second lateral trailing edge is defined by the intersection of the second tip face surface with the first lateral side surface. A chisel edge is defined at the converging intersection of the first and second tip face surfaces.
    Type: Grant
    Filed: April 4, 1988
    Date of Patent: January 15, 1991
    Assignee: Vermont American Corporation
    Inventors: Donald C. Pennington, Jr., John D. Knox
  • Patent number: 4975003
    Abstract: A drill having a shank formed with helical or straight flutes for discharging chips therethrough and a pair of cutting edges formed at one end of the shank and extending continuously from the center of rotation of the drill to the periphery thereof. Each of the flutes is defined by a wall which is positioned rearward with respect to the direction of rotation of the drill and against which a flat plate portion of the chip formed by the portion of the cutting edge on the peripheral side is to be pressed, and by a wall positioned forward with respect to the direction for a side edge portion of the chip to come into contact with. The forward wall is inclined with respect to the rearward wall so as to prevent the chip from curling in its entirety. The drill is given improved rigidity and adapted to discharge chips as broken into fragments of suitable length.
    Type: Grant
    Filed: March 21, 1990
    Date of Patent: December 4, 1990
    Inventor: Toshiaki Hosoi
  • Patent number: 4948306
    Abstract: A drill has a solid material shank (10), which is provided in its front region with a cold-forged drill point (11) with two cutting edges (12) approximately parallel to one another in projection and two flutes (13) running approximately in the longitudinal direction of the shank (10).
    Type: Grant
    Filed: August 5, 1988
    Date of Patent: August 14, 1990
    Assignee: Aldof Wurth GmbH & Co. KG
    Inventors: Karl Wiedner, Katsumi Shinjo
  • Patent number: 4932815
    Abstract: A tool in the form of a tapering borer or reamer has cutting portions adjacent the body of the tool with chip-receiving grooves therebetween, arranged alternately around the periphery of the tool. The cutting portions and the grooves may be of a helical configuration or may extend in a straight configuration parallel to the longitudinal axis of the tool. Each cutting portion has a cutting face and a relief face which intersect at a cutting edge. The cutting face defines a rake angle with respect to a first reference plane while the relief face defines a relief angle with respect to a second reference plane which is normal to the first reference plane.
    Type: Grant
    Filed: February 17, 1989
    Date of Patent: June 12, 1990
    Assignee: H. Willy Krauss GmbH & Co.
    Inventor: Helmut Krauss
  • Patent number: 4927303
    Abstract: In a ball end mill, a rotational locus is described by cutting edges of respective throw-away tips mounted to a tool body. The cutting edge of one of the tips and the cutting edge of the adjacent tip overlap with each other, and the center of the overlapping portion is located at a position that is substantially 45.degree. from a forward end of the cutting edge along a 1/4 arc of the rotational locus therefrom. The overlapping length is 1/4 to 1/3 of a diameter of the rotational locus in an arcuate length thereof. A planar section is formed at a side surface of at least one of the tips, which is located at a forward end of the tool body. The side surface is located adjacent a forward end of the cutting edge. A planar surface is formed at at least one of the tip pockets formed in the tool body, at a position facing toward the planar section. The planar surface is subject to a radial cutting force acting from the throw-away tip having the planar section. The planar section is abutted against the planar surface.
    Type: Grant
    Filed: September 26, 1989
    Date of Patent: May 22, 1990
    Assignee: Mitsubishi Metal Corporation
    Inventors: Osamu Tsujimura, Masaaki Nakayama, Masayuki Okawa
  • Patent number: 4913603
    Abstract: A two-flute drill bit includes two drill webs each provided with a cutting lip. The cutting lips are unequally angularly spaced from each other and the smaller one of two pitch angles included between two cutting lips is preferably 160.degree.. One of the webs has two peripheral margin lands spaced from each other whereby a three-point guidance of the drill bit is obtained.
    Type: Grant
    Filed: July 18, 1988
    Date of Patent: April 3, 1990
    Assignee: Sphinzwerke Muller AG
    Inventors: Paul Friedli, Georges Petignat, Jean-Marc Salomon
  • Patent number: 4906146
    Abstract: A drill bit having an elongated, stiffly flexible shank and integral, hardened, enlarged cutting head and tip is adapted to maintain a penetration angle through a plurality of spaced wooden objects while being rotatably driven by a drill. The tip of the drill bit forms a portion of a cutting head and is of generally triangular shape having two relatively enlarged opposed flat surfaces joined by two tapered surfaces. The tapered surfaces intersect at a tip edge defined by a line which makes an acute angle with a plane bisecting said drill bit along the longitudinal axis thereof, and which plane is perpendicular to the flat surfaces.
    Type: Grant
    Filed: June 13, 1984
    Date of Patent: March 6, 1990
    Inventor: Roy E. Bowling
  • Patent number: 4904130
    Abstract: A drill bit, circular saw blade, milling head or other cutting tool on which are disposed a repeating series of color coded marks spaced uniformly at small predetermined increments so that they can be seen and distinguished while the tool is in use and can therefore be used as depth gauges for cutting, shaping or drilling to a desired depth.
    Type: Grant
    Filed: January 11, 1989
    Date of Patent: February 27, 1990
    Inventor: Jeremy W. Gorman
  • Patent number: 4897001
    Abstract: An apparatus and method for removing a head gimbal from a head stack assembly without causing damage to adjacent head gimbals and minimizing damage to the head stack assembly. The tool driver of a miniature drill is inserted through holes in the stack assembly and attached head gimbals to the position of the head gimbal to be removed. A removable cutting tool is attached to the tool driver and the head gimbal is drilled free of the head stack assembly.
    Type: Grant
    Filed: February 25, 1988
    Date of Patent: January 30, 1990
    Assignee: Computer & Communications Technology Corp.
    Inventor: Allen G. Rumpler
  • Patent number: 4889456
    Abstract: In a drilling tool for drilling in solid metal material, in particular for drilling in plate stacks (plate drill), two geometrically similar reversible carbide tips (2, 3) are arranged at different radial distances at the end of the shank (1) and offset from each other by 180.degree. in the circumferential direction, whose working ranges overlap, and each of which comprises several cutting edges (2a, 2b, 3a, 3b) of equal length. Of the cutting edges (2a, 2b, 3a, 3b), respectively two adjacent cutting edges at an obtuse angle (.alpha.) to each other are simultaneously in contact, wherein the radially inner, first reversible carbide tip (2) extends by its cutting edge (2b) which is in contact slightly beyond the drill axis (A), and the radially outer, second reversible carbide tip (3) is axially set back from the first reversible carbide tip (2), and its two operative cutting edges (3a, 3b) form acute angles (.beta.1, .beta.2) of different size with the drill axis (A).
    Type: Grant
    Filed: January 19, 1989
    Date of Patent: December 26, 1989
    Assignee: Komet Stahlhalter- und Werkzeugfabrik Robert Breuning GmbH
    Inventor: Bernd Killinger
  • Patent number: 4889455
    Abstract: A drill for stack drilling comprises a drill body, a central cutting insert, and a peripheral cutting insert. The inserts have active cutting edges arranged such that the drill successively cuts radially outwardly from the center of the drill in order to avoid the formation of break-out slugs. The active cutting edge of the central insert has three cutting edge portions forming obtuse angles with one another. The radially innermost one of those cutting edge portions is shorter than each of the other two cutting edge portions.
    Type: Grant
    Filed: May 18, 1988
    Date of Patent: December 26, 1989
    Assignee: Sandvik AB
    Inventors: Kurt O. Karlsson, Leif E. Karlsson
  • Patent number: 4859123
    Abstract: An insert boring tool includes radially outward and inward cutting inserts mounted thereon. The radially outward and inward inserts are arranged such that end cutting edges of the respective inserts are intersected with each other at a point of intersection in loci of rotation of the respective inserts in a plane containing an axis of a tool body. The radially outward and inward inserts are positioned such that, assuming that a radial distance between the point of intersection and a radially outermost end of the end cutting edge of the radially outward insert is A, and a radial distance between the point of intersection and a radially innermost end of the end cutting edge of the radially inward insert is B, a ratio of A/B takes a value of from 2/8 to 45/55.
    Type: Grant
    Filed: October 13, 1987
    Date of Patent: August 22, 1989
    Assignee: Mitsubishi Kinzoku Kabushiki Kaisha
    Inventors: Yuzo Koesashi, Yasuhiko Kawade, Yoshikazu Iwata
  • Patent number: 4844670
    Abstract: A cutter for the deburring of bores comprises a rectangular edged cutter element having taperingly extending cutting edges, having clearance surfaces ground undercut and comprising a convexly ground contact surface on one end of the cutter head for contact with the internal surface of a bore. Two oppositely aligned cutter elements are mounted for displacement in a radial direction in a guide recess of a tool holder, and while in the operative position during the deburring of a bore, the cutting elements are displaced inwards radially because of the tool holder feed and because of the tapered extension of the cutting edges, against a spring force in the guide recess, until they finally reach the inner area of the bore in the non-cutting mode.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: July 4, 1989
    Inventor: Heinrich Heule
  • Patent number: 4818156
    Abstract: A drill for performing a roughing cut in a workpiece as the drill is advanced, and performing a finishing cut as the drill is retracted. A blade carrier is mounted eccentrically on the drill to be movable between first and second positions. In the first position, the blade is located for a roughing cut. In the second position, the blade is shifted radially for a finishing cut. A spring biases the carrier toward the second position and yields when the carrier moves to the first position. The spring bias is too weak to overcome reaction forces acting on the blade during a roughing cut, wherein the roughing cut reaction forces cause the carrier to be shifted to the first (roughing cut) position. The spring bias is strong enough to overcome the weaker reaction forces occurring during a finishing cut, so that the carrier is automatically shifted to the second (finishing cut) position when the drill is withdrawn through the workpiece.
    Type: Grant
    Filed: June 17, 1988
    Date of Patent: April 4, 1989
    Inventor: Walter Bauer
  • Patent number: 4802799
    Abstract: A drill bit tip construction wherein the cutting edge at the tip of the drill bit is arranged to cause fragmentation of the chips being removed from the work metal during the drilling operation. The cutting edge of the drill bit at the drilling tip is made to be wavy and, in the illustrated embodiment, is defined by a plurality of segmentally cylindrical grooves extending parallel to the longitudinal extent of the flutes at the tip. In the illustrated embodiment, the grooves have a radius of approximately 0.05" and a length substantially greater than the radius to permit repeated resharpening of the drill bit with resultant reforming of the desired wavy cutting edge in the resharpened tip. In the illustrated embodiment, the cutting edge is formed in an insert secured as by brazing in a diametric slot at the tip. The insert may be formed of a carbide material having optimum cutting characteristics. The grooves are provided in the insert by use of an electric discharge wire cutting machine.
    Type: Grant
    Filed: June 10, 1987
    Date of Patent: February 7, 1989
    Assignee: Marken Tool Company
    Inventor: Marko I. Rachev
  • Patent number: 4776241
    Abstract: A cutting tool comprising a shank having a substantially diametrical cut through one end of the shank and having the diametrically opposed limbs formed by such a cut bent radially outwardly from the axis of the shank. Cutting blades are secured to the flat surfaces of the limbs formed by the cut. Preferably, the limbs are bent outwardly in opposite directions along the plane of the cut, and the edges of overlapping portions of the limbs are welded together to strengthen the cutting tool.
    Type: Grant
    Filed: February 13, 1984
    Date of Patent: October 11, 1988
    Inventor: Bernard Pollington
  • Patent number: 4768901
    Abstract: A drill having two or more cutting edges is provided with interchangeable cutting members. The cutting members are fastened by screws in corresponding recesses formed in the drill bit. The cutting members are embodied by interchangeable plates and provided with fastening portions behind the main cutting edge, in the direction of cutting. The screws engage through these fastening portions in threaded bores formed in the front face of the drill bit.
    Type: Grant
    Filed: March 30, 1987
    Date of Patent: September 6, 1988
    Assignee: Firma Gottlieb Guhring
    Inventors: Josef Reinauer, Hans G. Kuhl
  • Patent number: 4759667
    Abstract: A four surface point type drill has its primary clearance faces configured so that their circumferential width decreases as the longitudinal axis of the drill is approached. The trailing edge and cutting edge of the primary clearance face surfaces substantially intersect each other at a point where they both intersect the opposite ends of the chisel edge of the drill point. The chisel edge itself is totally defined by a line formed by the intersection of the two secondary clearance face surfaces of the drill point. This new improved drill point geometry permits the use of reduced primary and secondary clearance face relief angles at the drill point which improves the structural integrity of the cutting edge of the drill and hence reduces chipping at the cutting edge.
    Type: Grant
    Filed: November 8, 1985
    Date of Patent: July 26, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Technologies, Inc.
    Inventor: Charles R. Brown
  • Patent number: 4756650
    Abstract: A twist drill including a body characterized by the outer portion of each of the heels bulging toward the main flute as compared with that of the standard twist drill, the main lips each bulging in a triangular shape in cross section toward the main flute as compared with that of the standard twist drill, and a subflute having a substantially U-shaped cross section and axially formed in the inner portion adjacent to the axis of the twist drill of each of the heels along the main flute for a predetermined distance from the tip.
    Type: Grant
    Filed: November 26, 1986
    Date of Patent: July 12, 1988
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Koichiro Wakihira, Michitaka Katsuta, Masayasu Hino, Kouhei Matsumoto, Yoshio Nakahara, Tosio Sasayama
  • Patent number: 4725175
    Abstract: A drilling and thread forming fastener is provided having a threaded shank and a pilot end.A pair of cutting surfaces are provided on the pilot end, each surface terminating in a cutting edge having a linear groove, arcuate in cross-section disposed adjacent the cutting edge.
    Type: Grant
    Filed: September 17, 1986
    Date of Patent: February 16, 1988
    Assignee: USM Corporation
    Inventor: George Jesson
  • Patent number: 4712952
    Abstract: The invention relates to a drill for generating of holes in a work piece, preferably in a composite material. The drill comprises a cylindrical shank portion, two cutting portions projecting in the axial and radial direction of the drill and two chip gullets. The cutting portions are arranged symmetrically about the center axis of the drill and each comprising a cutting tip, a minor cutting edge and a free-cutting edge. The cutting portions are shaped such that they require a small feed force in order to drill in the work piece.
    Type: Grant
    Filed: March 4, 1986
    Date of Patent: December 15, 1987
    Assignee: Santrade Limited
    Inventors: Karl B. Isaksson, Bror G. K. Svahn
  • Patent number: 4710072
    Abstract: The countersink to form a conical chamfer at the mouth of a bore hole has a conical chamfering head, on which three separate cutting plates are arranged, symmetrically, the cutting plates being fastened to the chamfering head, but removable and changeable. A compatible sharpening device permits the introduction and mounting of the cutting plates, wherein the sharpening device has the same form or shape as the countersink, so that it is easy to resharpen the cutting plates to their original specifications.
    Type: Grant
    Filed: June 5, 1984
    Date of Patent: December 1, 1987
    Inventor: Heinrich Heule
  • Patent number: 4710070
    Abstract: A device in back spot facing tools of the kind comprising a spindle (11), at one front end portion (12) of which, at least one wing (14) is arranged in a recess (13) and pivotally mounted parallel with and eccentrically with respect to the spindle about an axle (15, 16). The wing is at the rotation of the spindle arranged to pivot from an inactive position within the circumference of the spindle to an active position outside it. It is at the part of the wing located outside of the spindle provided with at least one cutting edge and/or a cutter (17). The pivoted part of the wing (14) outside the spindle (12) is at least at its one preferably its front end surface (21) designed with an inclined ramp (22), which in the extended position of the wing, has its maximum height, as seen in the axial direction of the wing, in a portion located closest to the circumference of the spindle (12) and is arranged to incline towards the external, curved envelope surface (23 ) of the wing.
    Type: Grant
    Filed: February 18, 1986
    Date of Patent: December 1, 1987
    Assignee: Erix Tool AB
    Inventors: Per Alsen, Timo Salo
  • Patent number: 4688972
    Abstract: In a twist drill in which the outer portion in each of the chisel edge lines at the drill point is made permanently efficient in cutting by a wall surface of an additional inner groove united to the original flute, an improvement resides in that the inner portion thereof adjacent to the center also functions as an efficient cutting edge in creating a built-up edge deposited over a specified resting face of a narrow triangular shape close to the center, in which the resting face is bordered by the inner portion and an intersecting curve passing through an intermediate point in the chisel edge line, whereby a permanent cutting effect is achievable all over the length of each of the chisel edge lines in regrinding the drill point.
    Type: Grant
    Filed: March 26, 1986
    Date of Patent: August 25, 1987
    Inventor: Masao Kubota
  • Patent number: 4687388
    Abstract: A drill bit is provided with a pair of cutting edges which are positioned so that a narrow slot is formed therebetween in an area including the rotational axis of the drill bit and so that the lines joining the rotational axis of the drill bit and the innermost points of the respective cutting edges are at an angle not larger than about 160.degree. with each other as viewed in the axial direction of the drill bit.
    Type: Grant
    Filed: May 22, 1986
    Date of Patent: August 18, 1987
    Assignee: Toshiba Tungaloy Co., Ltd.
    Inventors: Yuzo Yokota, Atsushi Endo
  • Patent number: 4678380
    Abstract: A deburring tool for reaming inner and outer diameter end portions of tube and pipe-like workpieces includes a cast housing having an integrally formed conical support member therein. The conical support member has a base portion disposed adjacent one end of the housing and an apex area spaced toward the other end of the housing. Radially disposed apertures having a predetermined width dimension divide the conical support member into a plurality of wedge portions. A blade assembly is comprised of a plurality of separate blades which are fixedly secured to each other in a pattern identical to the pattern of apertures in the support member. The blades have a thickness dimension which is greater than the width dimension of the apertures in order that the blade assembly will be retained in the conical support member by a press-fit relationship established between the blades and apertures.
    Type: Grant
    Filed: January 17, 1986
    Date of Patent: July 7, 1987
    Assignee: Crawford Fitting Co.
    Inventors: Emery J. Zahuranec, James C. Musil
  • Patent number: 4645389
    Abstract: A multiple-toothed drill bit having at least three teeth is provided with front end cutting edges having respective outer and inner cutting edge sections oriented angularly to each other and meeting at respective frontwardmost cutting points located in a common plane, and with an axial centering spur having laterally outwardly and rearwardly inclined center cutting edges merging with the inner front end cutting edge sections via respective frontwardly concave cutting edge sections.
    Type: Grant
    Filed: December 10, 1984
    Date of Patent: February 24, 1987
    Assignee: Hartmetallwerkzeugfabrik Andreas Maier GmbH & Co.
    Inventor: Andreas Maier
  • Patent number: 4624830
    Abstract: A method of manufacturing by a powder metallurgy process a rotary drill bit including a bit body having a plurality of cutting elements mounted on the outer surface thereof comprises the steps of forming a hollow mould for moulding at least a portion of the bit body, packing the mould with powdered matrix material, and infiltrating the material with a metal alloy in a furnace to form a matrix. Before packing the mould with powdered matrix material, there are positioned in spaced locations on the interior surface of the mould a plurality of cutting elements, each of which is formed of a material, such as a polycrystalline diamond material, which is thermally stable at the temperature necessary to form the matrix. Also positioned in the mould, adjacent the rearward side of each cutting element, is a support material such that, at least after formation of the matrix, the support material has a higher modulus of elasticity than the matrix.
    Type: Grant
    Filed: November 30, 1984
    Date of Patent: November 25, 1986
    Assignee: NL Petroleum Products, Limited
    Inventor: John D. Barr
  • Patent number: 4621637
    Abstract: This invention is directed to an improved surgical tool to remove tissue or bone from a bone joint member prior to installing a prosthetic device wherein the device basically comprises a cutting head and a rotary device member. The cutting head comprises a support base coupled to the rotary drive, a hollow shell with one or more slots, and one or more cutting or skiving blades projecting through the slots and supported by the support base.
    Type: Grant
    Filed: July 30, 1984
    Date of Patent: November 11, 1986
    Inventor: Meyer Fishbein
  • Patent number: 4591303
    Abstract: A plurality of cutting tips are mounted on the distal end of the cylindrical main body of a drilling tool for performing trepanning. These tips are disposed along the circumferential direction of the main body and equidistantly spaced apart from one another. The force, which is produced by all of the cutting tips and acting at right angles to the axis of the main body, is smaller than the component of the cutting force, which is produced by each tip and acting at right angles to the axis of the main body. The cutting widths of the tips in the radial direction of the main body are substantially equal. One of the tips, which is located at an intermediate position in the radial direction, has a V-shaped leading portion.
    Type: Grant
    Filed: December 13, 1983
    Date of Patent: May 27, 1986
    Assignees: Tokyo Shibaura Denki Kabushiki Kaisha, Toshiba Tungaloy Co., Ltd.
    Inventors: Yoshihiro Sato, Kenichi Sasaki, Tatsuo Miyamoto, Hideo Tsuzaka
  • Patent number: 4585375
    Abstract: A cutter insert is provided which is adapted to be supported on a flat platform on a cutter body and abutting edgewise against walls upstanding from said platform. The insert comprises a flat block of cutting material in the geometric shape of a parallelogram having a hole extending therethrough between the upper surface and the mounting surface of the block to receive a screw for securing the block to the platform. The upper surface of the block terminates at opposite ends in radii. The cutter insert further includes a rake face and a clearance face on opposite sides of the hole with said upper surface and said faces constituting cutting edges defined by the intersections of said faces and said upper surface, and an angular facet at diagonally opposed ends of said radii so as to form a chip splitter at the juncture of the cutting edge of the rake face and the cutting edge of the angular facet.
    Type: Grant
    Filed: February 10, 1984
    Date of Patent: April 29, 1986
    Assignee: General Electric Company
    Inventor: Donald S. Erkfritz
  • Patent number: 4580934
    Abstract: A rotary hole sizing tool for enlarging a pre-existing hole comprising a shank portion, a disk-like cutting member having cutting edges formed on the axially advancing face thereof, a pilot member for engaging the walls of the pre-existing hole and aligning the cutting member on the center of the pre-existing hole, the pilot member including a stepped shoulder of reduced diameter forming an undercut clearance between the pilot member and the cutting member, and screw means for securing the pilot member and the cutting member to the mandrel.
    Type: Grant
    Filed: December 12, 1983
    Date of Patent: April 8, 1986
    Inventor: Wallace W. McCormick
  • Patent number: 4568227
    Abstract: An asymmetrical drill bit. A masonry-type bit having diametrically opposed, oppositely inclined top walls converging at an apex and having upstanding sidewalls is broken so that diametrically opposed, hollow ground, dished surfaces are formed such that the respective lengths of the top and sidewalls are diminished. The dished portions so formed are asymmetrical to the axis of rotation of the bit, and the structure exhibits a durability that substantially exceeds the durability of symmetrically ground bits.
    Type: Grant
    Filed: June 20, 1983
    Date of Patent: February 4, 1986
    Inventor: Donald L. Hogg
  • Patent number: 4568229
    Abstract: A drill screw having primary and secondary cutting edges on opposite sides of its longitudinal axis, with the primary cutting edge offset so that it contacts the work-piece first, at a position displaced laterally from the screw axis, and produces initial very rapid drilling of an opening through the work-piece, followed by a period of drilling by both cutting edges. A conical portion is also preferably provided on the screw which extends divergingly from the cutting edges toward the head end of the screw until its diameter matches the root diameter of the screw.
    Type: Grant
    Filed: April 8, 1985
    Date of Patent: February 4, 1986
    Assignee: Construction Fasteners, Inc.
    Inventor: Tommy R. Hulsey
  • Patent number: 4565471
    Abstract: A drill bit comprises a body having a shank portion and an end face at its forward end. The drill bit body has at the forward end a cutting means having at least one cutting edge provided on the end face. The cutting edge is spaced from the axis of rotation of the body. The body has a rake surface which terminates in the cutting edge and extends along the axis of rotation.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: January 21, 1986
    Assignee: Mitsubishi Kinzoku Kabushiki Kaisha
    Inventors: Hideo Negishi, Kaoru Goto, Sueji Takaya
  • Patent number: 4551918
    Abstract: A set of two cutting units are located on the end of a tool to be rotated. The cutting units are radially aligned and on a bevel. Each blade on each cutting unit has a radial rake of at least 60 degrees, a clearance angle, and serrations cut at an angle normal to the cutting edge to provide a series of points extending along that cutting edge.
    Type: Grant
    Filed: March 26, 1984
    Date of Patent: November 12, 1985
    Assignee: The Boeing Company
    Inventor: Dudley G. Smithberg
  • Patent number: 4545711
    Abstract: A milling tool for cutting internally of a bore by means of replaceable bits. The tool comprises an elongate bar member an end portion of which includes a pair of axially outer portions which extend radially outwardly from a central portion and are disposed on respectively opposite sides of the rotational axis. A pair of clamping members are detachably attached to the bar member on respectively opposite sides of the rotational axis and have axially outer portions which together with the axially outer portions of the bar member form an axially outer surface of the tool. The axially outer portions of the bar member and the clamping members cooperate to form four slots in the tool axially outer surface for clamping engagement of radially extending bits.
    Type: Grant
    Filed: March 9, 1982
    Date of Patent: October 8, 1985
    Assignee: The Babcock & Wilcox Company
    Inventor: Jimmy B. Dooley
  • Patent number: 4507028
    Abstract: A cutting tool combining a front drill part and a rear reamer part along one axial line, having twist drill flutes through both parts and reamer cutting edges spiraling in the opposite direction to that of the drill cutting edges, whereby the tool can provide a through hole in a workpiece having a smooth surface with one forward rotating operation.
    Type: Grant
    Filed: September 23, 1982
    Date of Patent: March 26, 1985
    Assignee: Densaburo Sakai
    Inventor: Masahiro Matsushita
  • Patent number: 4505626
    Abstract: A cutting tool having an upper cylindrical body and a lower cylindrical body with flat surfaces on opposite sides of the lower cylindrical body, flutes in said lower cylindrical body and three triangular cutting elements indexible to three separate positions secured in said lower cylindrical body and means for detachably securing said triangular cutting elements, one of said cutting elements having three cutting edges for each position and the other two of said cutting elements having one cutting edge for each position.
    Type: Grant
    Filed: February 24, 1983
    Date of Patent: March 19, 1985
    Assignee: Dexport Tool Company, Inc.
    Inventor: Craig Benhase
  • Patent number: 4473070
    Abstract: An intramedullary reamer comprising a tapered cylindrical body member, a groove extending along the opposite sides and across the small end of the body member, a plurality of longitudinally disposed valleys disposed in advance of the groove to facilitate removal of cutting chips and a replaceable blade adapted to fit into the groove in the body member, the cutting edge of the blade being exposed above said groove, the open end of the blade being provided with locking means to secure the blade to the body member.
    Type: Grant
    Filed: January 5, 1983
    Date of Patent: September 25, 1984
    Assignee: Regents of the University of Michigan
    Inventors: Larry S. Matthews, Steven A. Goldstein