JP5301307B2 - Single crystal diamond end mill and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further improve the durability of a single-crystal diamond end mill including a cutting edge and a rake face formed by use of artificial diamond which can provide stable quality as a material by improving the wear resistance thereof. <P>SOLUTION: A first ridge line 66 part of a regular square pole-like diamond material 64 is fitted to a V-shaped groove 62 provided in parallel to a tool axis O in a tool body 52, and a pair of side surfaces 68 adjacent to the first ridge line 66 is positioned and integrally fixed to be closely fitted respectively to a pair of wall surfaces of the V-shaped groove 62. A rake face 72 is formed by removing a second ridge line 70 part located in a diagonal position relative to the first ridge line 66, and one side edge of the rake face 72 is used as a peripheral cutting edge 74. Thus, the wear resistance of the peripheral cutting edge 74 is improved, compared with the case of using a ridge line of artificial diamond as the peripheral cutting edge as it is, and the durability is improved. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a single crystal diamond end mill, and more particularly to a technique for further improving durability by improving wear resistance.

  A diamond end mill is known in which a diamond tip is integrally fixed to a tip attachment portion of a shaft-shaped tool body, and is rotated around a tool axis O to perform cutting with a cutting edge provided on the diamond tip. (See Patent Document 1). As such a diamond, it is considered to use a single crystal artificial diamond as a material. Single crystal artificial diamond is basically a hexahedron shape with six {100} faces, that is, a cube or a rectangular parallelepiped whose adjacent faces are perpendicular to each other. Is small and stable quality can be obtained.

Japanese Patent Laid-Open No. 7-204922

  FIG. 4 is a view for explaining an example of an end mill using the artificial diamond, which is not yet known. The artificial diamond 10 in FIG. 4 (a) is a plate shape in which all planes 12 are constituted by {100} planes. As shown in (c), the tool body 16 is formed with a flat tip mounting seat 14 parallel to the tool axis O at the tip mounting portion as shown in (b). One of the ridge lines that are integrally fixed via a silver solder or the like and parallel to the tool axis O is used as the outer peripheral blade 18. Further, the ridge line at the tip continuous with the outer peripheral blade 18 is used as the bottom blade 20, and the upper surface functions as the rake face 22. That is, since such an artificial diamond 10 is difficult to process, one of the {100} faces is used as the rake face 22 as it is, and the ridge line located at the edge of the rake face 22 is used as the outer peripheral edge 18 and the bottom edge. It is used as 20. These outer peripheral blade 18 and bottom blade 20 are provided with relief as needed, and a chamfered relief 24 is provided at the tip opposite to the outer peripheral blade 18 to avoid interference.

  The “{...}” Is a Miller index and represents a crystal plane in which atoms are arranged in a fixed arrangement. Further, the artificial diamond 30 shown in FIG. 3D has a shape having a chamfered plane 32 at the corner, and this chamfered plane 32 is generated depending on the manufacturing conditions of the artificial diamond 30 and the like. In the present specification, including the artificial diamond 30 having such a chamfered flat surface 32, it will be basically referred to as a hexahedral monocrystalline artificial diamond.

  By the way, since the {100} plane has relatively dense atoms, the rake face 22 has excellent wear resistance, but is parallel to the {100} plane and parallel to the ridgeline, that is, parallel to the ridgeline. The outer peripheral blade 18 and the bottom, which have a low abrasion resistance against the xyz triaxial polishing, and have a polishing action in any one of the three axes (the z axis direction in FIG. 4 (c)). There was a problem that the blade 20 was easily worn and the expected durability could not be obtained.

  The present invention has been made in the background of the above circumstances. The object of the present invention is to provide a single crystal diamond end mill having a diamond tip provided with a cutting edge and a rake face made of an artificial diamond capable of obtaining stable quality. It is to improve the wear resistance and further improve the durability.

  According to the first aspect of the present invention, a diamond tip provided with a cutting edge and a rake face made of hexagonal single crystal artificial diamond having six {100} faces as a material is provided at the tip attachment portion of an axial tool body. In a single crystal diamond end mill that is integrally fixed and is rotated around the tool axis O to perform cutting with its cutting edge. (A) The tip mounting portion includes a tool axis O and A V-shaped groove having a right-angled cross-section forming a right-angled V-shape is provided in parallel with the tool axis O, and the first ridge portion of the hexagonal artificial diamond is fitted into the V-shaped groove. A pair of side surfaces adjacent to one ridge line are positioned and fixed integrally so as to be in close contact with the pair of wall surfaces of the V-shaped groove, respectively. (B) The first ridge line fitted into the V-shaped groove. Versus Said rake face is formed by the second ridge line portion of the position is removed, the edge of the rake face characterized in that it is used as the cutting edge.

  According to a second aspect of the present invention, in the single crystal diamond end mill of the first aspect, the rake face is a flat {110} plane formed by being removed symmetrically across the second ridgeline, or its {110} It is a flat surface formed by being removed asymmetrically across the second ridge line so as to incline within a range of ± 10 ° from the surface.

  A third invention is the single crystal diamond end mill according to the first or second invention, wherein the V-shaped groove passes through the tool axis O and the groove bottom vertex of the V-shaped groove in a cross section perpendicular to the tool axis O. It is characterized in that the straight line and the center line S of the V-shaped groove coincide with each other or are inclined in a range of ± 10 °.

  A fourth invention is the single crystal diamond end mill according to any one of the first to third inventions, wherein the artificial diamond material has a quadrangular prism shape, and the center line of the quadrangular prism shape is the tool axis O. The V-groove is integrally fixed in a parallel posture.

  A fifth invention is a method for producing a single-crystal diamond end mill according to any one of the first to fourth inventions, wherein (a) the artificial diamond material is integrated with the V-shaped groove of the tool body by brazing. And (b) in a state where the artificial diamond material is integrally fixed to the tool body, the second ridge line portion in the tool axis direction, that is, the direction parallel to the second ridge line. And polishing to form the rake face by polishing and removing.

  In such a single crystal diamond end mill, a first ridge line portion of hexahedral hexagonal diamond is fitted into a V-shaped groove provided in the tool body in parallel with the tool axis O, and a pair adjacent to the first ridge line. The side surfaces of the ridges are positioned so as to be in close contact with the pair of wall surfaces of the V-shaped groove and are integrally fixed, and the second ridge line portion at a diagonal position with respect to the first ridge line is removed to rake Since the surface is formed and the edge of the rake face is used as a cutting edge, the wear resistance of the cutting edge is improved and durable compared to the case where the ridgeline of hexagonal artificial diamond is used as it is as a cutting edge. Improves.

  In addition, the artificial diamond material, or the diamond tip formed with the rake face and the cutting edge, has a first ridge line portion fitted into the V-shaped groove, and a pair of side surfaces adjacent to the first ridge line are V-shaped grooves. Therefore, the accuracy of the diamond tip mounting position and mounting posture relative to the tool body can be easily and stably obtained. Further, since the contact area is larger than that of a single flat surface, the fixing strength by brazing or the like is increased, and the present invention can be suitably applied to a small-diameter end mill that cannot sufficiently secure the tip mounting portion.

  In the second aspect of the invention, the rake face is inclined within a range of ± 10 ° from the flat {110} plane formed by being removed symmetrically across the second ridgeline, or the {110} plane. Since this is a flat surface formed by being removed asymmetrically across the second ridge line, the wear resistance of the cutting edge formed on the side edge can be improved appropriately.

  In the third invention, in a cross section perpendicular to the tool axis O, the straight line passing through the tool axis O and the groove bottom apex of the V-shaped groove coincides with the center line S of the V-shaped groove or ± 10 °. Since the V-shaped groove is provided so as to incline within the range, the diamond chip is fixed in a balanced manner by this V-shaped groove, and the single crystal diamond end mill can be appropriately configured.

  In the fourth invention, the artificial diamond material has a quadrangular prism shape, and the center line of the quadrangular prism shape is integrally fixed to the V-shaped groove so as to be parallel to the tool axis O. Since the contact area between the artificial diamond material and the V-shaped groove is increased, a high mounting strength can be easily ensured.

  In the fifth invention, the artificial diamond material is integrally fixed to the V-shaped groove of the tool body by brazing, and then the second ridge line portion is ground and removed in the tool axis direction, that is, in a direction parallel to the second ridge line. Although the surface is formed, polishing in the direction parallel to the ridgeline is relatively easy, and since the material of the artificial diamond is fixed to the tool body, the rake face and cutting edge are easily processed with high accuracy. can do. In addition, the diamond tip is integrally fixed to the V-shaped groove of the tool body by brazing, but a large bonding area is obtained compared to a single flat surface, and a relatively small tip mounting portion can be obtained. Can be attached with a sufficient adhesive strength, and can be suitably applied to a small-diameter end mill that cannot sufficiently secure a tip attaching portion.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a single crystal diamond end mill according to an embodiment of the present invention, in which (a) is a front view, (b) is an enlarged view of a portion taken along arrow IB in (a), and (c) is a right direction of (b). (D) is a perspective view of a tool tip portion to which a diamond tip is attached. It is a figure explaining the manufacturing process of the single crystal diamond end mill of FIG. FIG. 4 is a diagram for explaining another embodiment of the present invention, in which (a) to (c) are front end views corresponding to FIG. 1 (c), and (d) is a perspective view of an artificial diamond corresponding to FIG. 2 (a). It is. It is a figure explaining an example of the end mill which uses the ridgeline of a single crystal artificial diamond as a cutting edge as it is.

  The single crystal diamond end mill of the present invention is suitably applied to, for example, a square end mill having a peripheral edge and a bottom edge as a cutting edge, a radius end mill, etc., but can also be applied to a ball end mill having a ball blade as a cutting edge, etc. The cutting edge should just be provided in the edge of the rake face at least. The cutting edge is provided with relief by polishing or the like as necessary, and on the opposite side across the tool center line, relief such as chamfering is provided as necessary to avoid interference.

  In the present invention, since the V-shaped groove provides high fixing strength and positioning accuracy, the outer diameter of the cutting edge (such as the edge diameter of the outer peripheral blade) is suitably applied to a small-diameter end mill having a diameter of about 3 mm or less, for example. It can also be applied to end mills exceeding 3 mm.

  Artificial diamonds are not only cubes or cuboids as shown in FIG. 4 (a), but also have chamfered planes at the corners of these cubes and cuboids as shown in FIG. 3 (d). Things can be used.

  A cemented carbide is preferably used as the material of the tool body, but other metal materials such as molybdenum can also be used. In the case of a tool body made of cemented carbide, it can be molded and sintered in a state having a V-shaped groove, but it is also possible to provide a V-shaped groove later by grinding or the like. In order to avoid interference between the bottom of the V-shaped groove and the ridgeline of the artificial diamond, a clearance groove having a rectangular cross section or an arc cross section is provided on the bottom of the V-shaped groove, or the ridgeline portion of the artificial diamond is polished and removed with a grindstone or the like. It is desirable. The polishing in this case only needs to remove the ridge line portion, and since accuracy is not required, it can be easily removed with a diamond grindstone or the like.

  The second ridge line portion can be removed by polishing or the like after attaching the artificial diamond to the tool body, but can also be removed by polishing or the like in the state of the artificial diamond alone before being attached to the tool body. The polishing process is preferably performed using a diamond polishing machine such as a Skyf machine, but can be removed by other processing techniques such as laser processing or a diamond grindstone. However, it is desirable to finish and polish with a Skyf board etc. at the end. By removing the second ridge line portion, for example, a flat rake face parallel to the tool axis O is formed, but a rake face such as a curved shape is formed so as to obtain a predetermined rake angle. Also good.

  In the single crystal diamond end mill of the present invention, it is appropriate to use the {110} plane or the vicinity thereof (inclination angle is ± 10 ° or less) as a rake face, and the substantially {110} plane having an inclination angle of ± 5 ° or less. However, if the rake face is formed by removing the second ridge, the tilt angle may exceed ± 10 °, and the balance and breakage around the tool axis O It is appropriately set in consideration of the rake angle of the blade.

  The V-shaped groove has a symmetrical orientation in which a straight line passing through the tool axis O and the groove bottom apex of the V-shaped groove coincides with the center line S of the V-shaped groove in a cross section perpendicular to the tool axis O, or ± 10 °. It is suitable to be provided in a posture that is inclined within the range of, and is preferably provided in a substantially symmetrical posture with an inclination of ± 5 ° or less, but it is also possible to provide an inclined posture exceeding ± 10 °, and the tool axis O It is set as appropriate in consideration of the balance around and the rake angle of the cutting edge.

  As the artificial diamond material, a quadrangular prism shape having a square or rectangular cross section, that is, a long one is preferably used, but a relatively short artificial diamond material such as a cube can also be used.

  As the means for fixing the artificial diamond material or the diamond tip after the rake face and cutting edge are formed on the tool body, brazing is desirable, but mechanical fixing means such as clamps and screws are adopted. It is also possible. An active metal braze is preferably used for brazing. Adhesion with an active metal braze produces an active metal film such as titanium (Ti) or chromium (Cr) on the surface by heating artificial diamond in a deoxygenated atmosphere (metallized), and a silver braze containing silver and copper. The artificial diamond is directly bonded to a tool body such as cemented carbide. In order to obtain a sufficient adhesion strength with the active metal brazing, a sufficient adhesion area is necessary. However, in the present invention, a large adhesion area can be secured by the V-shaped groove as compared with a single plane.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1A and 1B are diagrams for explaining a single crystal diamond end mill 50 according to an embodiment of the present invention. FIG. 1A is a front view seen from a direction perpendicular to the tool axis O, and FIG. (a) is a partial enlarged view as seen from the direction where the phase is 90 ° different, (a) is an enlarged view of the IB arrow portion, (c) is a front end view as seen from the right direction of (b), (d ) Is a perspective view of a tool tip portion to which a diamond tip is attached. The single crystal diamond end mill 50 includes a shaft-shaped tool body 52 and a diamond tip 56 that is integrally fixed to a cylindrical tip mounting portion 54 that is integrally provided at the tip of the tool body 52. Yes. The tool main body 52 has a tip mounting portion 54 concentrically and integrally provided on the tip side of a cylindrical shank 58 via a tapered portion 60, and the tip mounting portion 54 has a cross section perpendicular to the tool axis O. V-shaped groove 62 having a right-angled V-shape is provided in parallel to the tool axis O and is open at the tip of the tool. In a cross section perpendicular to the tool axis O, the V-shaped groove 62 has a symmetrical posture in which a straight line passing through the tool axis O and the groove bottom vertex of the V-shaped groove 62 and the center line S of the V-shaped groove 62 substantially coincide with each other. Is provided. The shape of the tip attachment portion 54 and the diamond tip 56 in the tip view of FIG. 1C is substantially the same as the cross section perpendicular to the tool axis O. The tool body 52 is made of cemented carbide.

  As shown in FIG. 2, the diamond tip 56 is manufactured using a regular quadrangular prism-shaped diamond material 64 cut out from the artificial diamond 10. In the diamond material 64, all the outer surfaces are constituted by {100} planes like the artificial diamond 10. The diamond material 64 has a longitudinal first ridge 66 fitted into the V-shaped groove 62 in a posture in which the center line is parallel to the tool axis O, and is adjacent to the first ridge 66. The pair of side surfaces 68 are positioned so as to be in close contact with the pair of wall surfaces of the V-shaped groove 62, and are integrally bonded (fixed) to the pair of wall surfaces of the V-shaped groove 62 by brazing with an active metal solder. In the bottom portion of the V-shaped groove 62, a relief groove having a rectangular cross section is provided in order to avoid interference with the first ridgeline 66. Further, the upper half of the second ridge line 70 at the diagonal position with respect to the first ridge line 66 fitted in the V-shaped groove 62 is removed in parallel with the tool axis O, and a flat rake face 72 is formed. While being formed, one side edge of the rake face 72 functions as the outer peripheral edge 74, and the front end edge of the rake face 72 functions as the bottom edge 76, and is used as a square end mill. The rake face 72 is symmetrically removed with the second ridge line 70 in between, and is constituted by a substantially {110} plane.

  The tip portion of the diamond tip 56 protrudes forward by a predetermined dimension from the tip mounting portion 54 of the tool main body 52, and cutting is mainly performed at the protruding portion, and on the opposite side across the tool axis O. In order to avoid interference, a chamfered relief 78 is provided. The outer peripheral blade 74 and the bottom blade 76 are also provided with relief as required. The cutting edge diameter d of the outer peripheral edge 74 is a small diameter of 3 mm or less, and is about 1 mm in this embodiment.

  Such a single crystal diamond end mill 50 is driven to rotate clockwise around the tool axis O as viewed from the shank 58 side (counterclockwise in FIG. 1 (c)), and at the same time with respect to the workpiece (not shown) By being relatively moved in a direction intersecting the center O, the outer peripheral blade 74 and the bottom blade 76 perform cutting. Specifically, for example, shoulder machining for corners, grooving for surfaces, and planar machining with continuous grooves can be performed.

  On the other hand, such a single crystal diamond end mill 50 is manufactured, for example, according to the procedure shown in FIG. FIG. 2 (a) shows the artificial diamond 10 having a thin plate shape and a hexahedron shape in which all the planes 12 are constituted by {100} planes, and this is processed by laser processing or grinding by a diamond blade along the ridgeline. By cutting the diamond material 64, a diamond material 64 having a regular quadrangular prism shape with a substantially square cross section is cut out as shown in FIG. Further, (c) is a cemented carbide tool body 52 prepared separately from the diamond material 64, and the V-shaped groove 62 can be provided at the stage of forming the shank 58, the tapered portion 60, or the like. It is also possible to form by grinding after sintering. In order to increase the bonding strength of the diamond material 64, finish grinding or the like may be performed so that the pair of wall surfaces of the V-shaped groove 62 has a predetermined surface accuracy.

  And, as shown in (d), before the rake face 72 is formed on the regular quadrangular prism-shaped diamond material 64, the first ridge line 66 in the longitudinal direction is in a posture in which the center line is parallel to the tool axis O. A pair of side surfaces 68 that are fitted into the V-shaped groove 62 and are adjacent to the first ridge line 66 are in close contact with the pair of wall surfaces of the V-shaped groove 62, and are integrally bonded by brazing with an active metal solder ( (Fixed). The active metal brazing is a silver brazing containing an active metal such as titanium (Ti) or chromium (Cr) at a ratio of about 2 to 4%, and the diamond material 64 is about 800 ° C. to 1000 ° C. in a deoxygenated atmosphere. By heating to a thickness, an active metal film such as titanium or chromium is formed on the surface of the side surface 68 (metallization), and the side surface 68 is directly bonded to the wall surface of the V-shaped groove 62 by silver brazing containing silver and copper. In this case, as shown in FIG. 1 (c), the relief groove is provided at the bottom of the V-shaped groove 62, so that the side surface 68 and the wall surface of the V-shaped groove 62 can be securely adhered to each other. The area is sufficiently secured and high adhesive strength can be obtained. Thus, the process of integrally bonding the diamond material 64 to the V-shaped groove 62 by the active metal brazing is a fixing process. In FIG. 2, the relief groove at the bottom of the V-shaped groove 62 is omitted.

  Thereafter, in a state in which the regular prismatic diamond material 64 is integrally fixed to the tool body 52 in this manner, a direction parallel to the tool axis O with respect to the diamond material 64 by a diamond polishing technique such as a Skyf machine. That is, by performing a polishing process in a direction parallel to the second ridge line 70, a flat rake face 72 parallel to the tool axis O is formed. By pressing in a linear direction connecting the first ridge line 66 and the second ridge line 70 so as to be polished symmetrically across the second ridge line 70, a rake face 72 constituted by a substantially {110} plane is formed. It is formed. Thereby, the diamond tip 56 provided with the rake face 72, the outer peripheral edge 74, and the bottom edge 76 is manufactured, and the single-crystal diamond end mill 50 of the present embodiment in which such a diamond tip 56 is integrally fixed. Is manufactured. In this step, reliefs are formed in the outer peripheral edge 74 and the bottom edge 76 as necessary, and the relief 78 is provided at the tip by a diamond grinding technique such as a slife board or a diamond grindstone. The process of forming the rake face 72 by removing the second ridge line 70 by polishing as described above is the polishing process.

  In such a single crystal diamond end mill 50 of this embodiment, the first ridge 66 portion of a regular square prism-shaped diamond material 64 is fitted into a V-shaped groove 62 provided in the tool body 52 in parallel with the tool axis O. The pair of side surfaces 68 adjacent to the first ridge line 66 are positioned and fixed integrally so as to be in close contact with the pair of wall surfaces of the V-shaped groove 62, and are also paired with the first ridge line 66. The rake face 72 is formed by removing the second ridge line 70 portion at the corner position, and one side edge of the rake face 72 is used as the outer peripheral edge 74. For example, as shown in FIG. Compared with the case where the ridgeline is used as the outer peripheral blade 18 as it is, the wear resistance of the outer peripheral blade 74 is improved and the durability is improved.

  In addition, the diamond material 64 has a first ridgeline 66 portion fitted into the V-shaped groove 62, and a pair of side surfaces 68 adjacent to the first ridgeline 66 are in close contact with the pair of wall surfaces of the V-shaped groove 62. Therefore, the accuracy regarding the mounting position and mounting posture of the diamond material 64 and the diamond tip 56 with respect to the tool main body 52 can be easily and stably obtained.

  Further, in the present embodiment, the rake face 72 is formed by being removed symmetrically with the second ridge line 70 in between, so that the rake face 72 is constituted by a substantially {110} plane. The wear resistance of the outer peripheral edge 74 formed on the side edge and the bottom edge 76 formed on the front edge is appropriately improved.

  In this embodiment, in a cross section perpendicular to the tool axis O, a symmetric posture in which a straight line passing through the tool axis O and the groove bottom apex of the V-shaped groove 62 and the center line S of the V-shaped groove 62 substantially coincide with each other. Since the V-shaped groove 62 is provided so that the diamond tip 56 is fixed in a balanced manner by the V-shaped groove 62, the single crystal diamond end mill 50 can be appropriately configured.

  In the present embodiment, the diamond material 64 has a quadrangular prism shape, and is integrally fixed to the V-shaped groove 62 in such a posture that the center line of the quadrangular prism shape is parallel to the tool axis O. Therefore, the contact area between the diamond material 64 and the V-shaped groove 62 is increased, and high mounting strength can be easily ensured.

  In this embodiment, after the diamond material 64 is integrally fixed to the V-shaped groove 62 of the tool body 52 by brazing, the second ridge line 70 is polished and removed in a direction parallel to the second ridge line 70. Although the rake face 72 is formed, polishing in a direction parallel to the ridge line is relatively easy, and since the diamond material 64 is fixed to the tool body 52, the rake face 72, the outer peripheral edge 74, and the bottom are polished. The blade 76 and the clearance 78 can be easily machined with high accuracy.

  Further, the diamond tip 56 is integrally fixed to the V-shaped groove 62 of the tool body 52 by brazing, but a large bonding area can be obtained compared to a single flat surface, and a relatively small tip mounting portion. The single-crystal diamond end mill 50 having a small diameter that cannot be secured sufficiently and can be appropriately configured can be attached to the terminal 54 with sufficient adhesive strength.

For this reason, the product of the present invention (single crystal diamond end mill 50 of this example) and the comparative product shown in FIG. Compared with the comparative product, which was 300 to 500 m, the product of the present invention was able to process 30000 to 50000 m, and the tool life was greatly improved.
"Processing conditions"
Work material: Aluminum alloy (JIS-A7075)
Cutting edge diameter d: φ1.0
Rotational speed: 20000 min ^-1
Feeding speed: 100mm / min
Cutting depth (groove depth): 5 μm

  Next, another embodiment of the present invention will be described. In the following embodiments, parts that are substantially the same as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  3 (a) to 3 (c) are front end views corresponding to FIG. 1 (c). In the embodiment of FIG. 3 (a), the rake face 80 formed on the diamond material 64 is the above-described embodiment. Is different. That is, the rake face 72 of the above embodiment is symmetrically removed with the second ridge line 70 in between, and is constituted by a substantially {110} plane, but the rake face 80 of this embodiment is { 110} surface is a flat surface formed by being removed asymmetrically across the second ridge line 70 so as to incline within a range of ± 10 °. In this embodiment, the edge angle of the outer peripheral edge 74 is more than 45 °. Is also inclined in the direction of decreasing. Even in this case, since the rake face 80 is only inclined within a range of ± 10 ° from the {110} plane, the wear resistance of the outer peripheral edge 74 and the bottom edge 76 is appropriately improved as in the above embodiment. Be made. Moreover, by setting the inclination of the rake face 80 appropriately, the rake angle of the outer peripheral edge 74 can be adjusted, and the degree of freedom in design is increased.

  FIG. 3 (b) shows a case where a rectangular prism-shaped diamond material 82 having a rectangular cross section is used. The diamond material 82 is reduced in width by reducing the width dimension of the diamond material 82 while ensuring the same edge diameter d as in the above embodiment. In addition, it is possible to reduce the machining allowance for the relief 78 and to reduce the manufacturing cost as a whole.

  FIG. 3C shows a case where the V-shaped groove 84 is further inclined in the embodiment of FIG. That is, in the V-shaped groove 84, a straight line passing through the tool axis O and the groove bottom apex of the V-shaped groove 84 and a center line S of the V-shaped groove 84 in a cross section perpendicular to the tool axis O is ± 10 °. In this embodiment, the tool is tilted at an angle of 10 ° or less toward the tool rotation direction when performing cutting, that is, in the left-handed direction of the tool axis O in FIG. It has been. Even in this case, the rake face 80 is only inclined within the range of ± 10 ° from the {110} plane as in FIG. 3A, and therefore the wear resistance of the outer peripheral edge 74 and the bottom edge 76 is improved. It can be improved appropriately. Further, by appropriately setting the inclination of the V-shaped groove 84, the rake angle of the outer peripheral blade 74 can be adjusted, and the degree of design freedom is increased.

  FIG. 3 (d) is a perspective view showing an artificial diamond 30 having a chamfered flat surface 32 at a corner, and the artificial diamond 30 is cut into a quadrangular prism shape and used as a material, and the single crystal diamond end mill is used. 50 can also be manufactured. A single-crystal diamond end mill 50 can be manufactured by manufacturing a square pillar-shaped artificial diamond such as the diamond material 64 or 82 and using it as a raw material as it is.

  As mentioned above, although the Example of this invention was described in detail based on drawing, these are one Embodiment to the last, This invention is implemented in the aspect which added the various change and improvement based on the knowledge of those skilled in the art. be able to.

  10, 30: Artificial diamond 50: Single crystal diamond end mill 52: Tool body 54: Tip mounting portion 56: Diamond tip 62, 84: V-shaped groove 64, 82: Diamond material (material) 66: First ridge 70: Second Edges 72, 80: Rake face 74: Peripheral edge (cutting edge) 76: Bottom edge (cutting edge) O: Tool axis S: Center line of V-shaped groove

Claims (5)

Basically, a diamond tip with a cutting edge and a rake face made of hexagonal single crystal artificial diamond with six {100} faces is fixed integrally to the tip mounting portion of the shaft-shaped tool body. In a single crystal diamond end mill that performs cutting with the cutting edge by being rotationally driven around the tool axis O,
The tip mounting portion is provided with a V-shaped groove having a right-angled V-shaped cross section perpendicular to the tool axis O in parallel with the tool axis O, and the first ridge line portion of the hexahedral artificial diamond is While being fitted into the V-shaped groove and positioned so that the pair of side surfaces adjacent to the first ridge line are in close contact with the pair of wall surfaces of the V-shaped groove, respectively, and fixed integrally therewith,
The rake face is formed by removing a second ridge line portion at a diagonal position with respect to the first ridge line fitted into the V-shaped groove, and an edge of the rake face is used as the cutting edge. Single crystal diamond end mill. The rake face is a flat {110} plane formed by being removed symmetrically across the second ridgeline, or the first rake face is inclined within a range of ± 10 ° from the {110} plane. The single crystal diamond end mill according to claim 1, wherein the single crystal diamond end mill is a flat surface formed by being removed asymmetrically across two ridge lines. In the V-shaped groove, in a cross section perpendicular to the tool axis O, a straight line passing through the tool axis O and the groove bottom vertex of the V-shaped groove coincides with the center line S of the V-shaped groove, or ± 10 °. The single-crystal diamond end mill according to claim 1, wherein the single-crystal diamond end mill is provided so as to be inclined within a range of. The artificial diamond material has a quadrangular prism shape, and is integrally fixed to the V-shaped groove in such a posture that the center line of the quadrangular prism shape is parallel to the tool axis O. The single crystal diamond end mill according to any one of claims 1 to 3. A method for producing the single crystal diamond end mill according to any one of claims 1 to 4,
A fixing step of integrally fixing the material of the artificial diamond to the V-shaped groove of the tool body by brazing;
A polishing step of forming the rake face by polishing and removing the second ridge line portion in the tool axis direction in a state where the artificial diamond material is integrally fixed to the tool body;
A process for producing a single crystal diamond end mill, comprising:

Images