JP2012011475A - Diamond-coated tool, and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure the excellent cutting quality by grinding a surface of a diamond film provided on a blade part so as to be sharpened until the blade tip width Φ is ≤100 nm.SOLUTION: In a scribing wheel (a diamond-coated tool) 10 including a blade part 16 with a diamond film 14 being coated thereon on a surface of a tool base material 12, a fore end ground part 24 is provided on a fore end part of the blade part 16, which is sharpened by grinding the diamond film 14 by applying ion beams so that the blade tip angle θis larger than the original blade tip angle θa, and the blade tip width Φ is 10-100 nm. The excellent cutting quality can be obtained irrespective of the diamond coating while ensuring the predetermined blade tip strength. In other words, the grinding by applying ion beams is executed in a non-contact manner, and any grinding load is not applied to the blade tip 20, and the blade tip can be ground sharp until the blade tip width Φ is ≤100 nm.

Description

  The present invention relates to a diamond-coated tool, and more particularly to a diamond-coated tool sharpened until the blade tip width Φ at the tip of the blade becomes 100 nm or less and a manufacturing method thereof.

  There has been proposed a diamond-coated tool in which a predetermined blade portion is formed by coating a surface of a tool base made of cemented carbide or ceramic with a diamond coating (see Patent Document 1). If the diamond film is coated in this way, the wear of the blade portion accompanying use is suppressed, and the tool life can be greatly improved.

JP 2002-370107 A JP 2007-137743 A

  However, when the diamond film is coated in this way, the film thickness of the diamond film is generally about 10 to 20 μm, and the tip of the blade portion is rounded with a radius close to the film thickness of the diamond film, resulting in poor sharpness. In some cases, the intended processing cannot be performed properly. For example, in the case of a glass cutting tool (see Patent Document 2) that scratches the glass with the tip of the blade part to cut the glass, or presses the tip of the blade part against the glass to make the hook. When coating is applied, the cutting edge becomes round and the glass cannot be cut appropriately. On the other hand, in Patent Document 1, it is proposed to polish the tip portion of the blade portion using a diamond grindstone or the like, but such mechanical polishing is easily chipped because a polishing load is applied to the blade edge. In addition, it is difficult to sharpen until the edge width Φ of the tip becomes 100 nm or less, and there are cases where it is still not fully satisfactory depending on the type of tool. The cutting edge width Φ is a width dimension such as roundness of the cutting edge.

  The present invention has been made against the background of the above circumstances, and its purpose is to polish the surface of the diamond coating provided on the blade portion until the cutting edge width Φ at the blade tip becomes 100 nm or less. The object is to sharpen and obtain an excellent sharpness regardless of the diamond coating.

  In order to achieve such an object, the first invention provides a diamond-coated tool in which a predetermined blade portion is formed by coating a diamond coating on the surface of a tool base material made of cemented carbide or ceramics. By polishing the surface of the provided diamond film by irradiating it with an ion beam, the tip of the blade is sharpened so that the tip of the blade has a blade width Φ within a range of 10 to 100 nm. A portion is provided.

According to a second aspect of the present invention, there is provided a diamond-coated tool in which a surface of a tool base material made of cemented carbide or ceramic is coated with a diamond coating to form a triangular-shaped blade portion having a predetermined cutting edge angle θa. By irradiating the surface of the diamond coating with an ion beam and polishing it, the tip portion of the blade portion has a cutting edge angle θ ₁ larger than the cutting edge angle θa and the cutting edge width Φ of the tip is 10 to 100 nm. A tip polishing portion sharpened so as to be inside is provided.

According to a third aspect of the present invention, in the diamond-coated tool of the second aspect, the diamond coating provided on the blade portion has a cutting edge angle θ ₂ that is larger than the cutting edge angle θa and smaller than the cutting edge angle θ _1. A polished intermediate polishing portion is provided, and the tip polishing portion is provided on the tip side of the intermediate polishing portion.

  According to a fourth invention, in the diamond-coated tool according to any one of the first to third inventions, the diamond-coated tool has a disk shape as a whole, and the entire circumference of the outer periphery of the disk shape. The scribing wheel is characterized in that the blade portion is provided so as to protrude toward the outer peripheral side, and a scribing wheel for scoring the glass at the tip of the blade portion when cutting the glass.

The fifth invention relates to a diamond-coated tool in which a diamond base is coated on the surface of a tool base material made of a cemented carbide or ceramics to form a triangular section with a predetermined cutting edge angle θa. A manufacturing method for polishing and sharpening a coating, comprising: (a) irradiating the surface of a diamond coating provided on the blade portion by irradiating with an ion beam so that the blade edge angle θa A first polishing step for forming an intermediate polishing portion having a larger cutting edge angle θ _2, and (b) changing the irradiation condition of the ion beam to irradiate the surface of the intermediate polishing portion to further polish, the blade width and the tip with a large included angle theta ₁ than the cutting edge angle theta ₂ [Phi forms the tip grinding unit which sharpened so as to be in the range of 10~100nm at the tip portion of the intermediate polisher And having a second polishing step.

According to a sixth aspect of the present invention, in the method for manufacturing a diamond-coated tool according to the fifth aspect, in the first polishing step, the acceleration voltage of the ion beam is changed and the processing angle α of polishing by irradiation of the ion beam is adjusted. The intermediate polishing portion that is inclined symmetrically with the cutting edge angle θ ₂ with respect to the blade center plane S is formed, and symmetrical with the cutting edge angle θ ₁ with respect to the blade center plane S in the second polishing step. The tip polishing portion that is inclined is formed.

  In the diamond-coated tool according to the first aspect of the invention, the diamond coating is polished by an ion beam, whereby a tip having a triangular cross section is sharpened at the tip of the blade so that the blade tip width Φ is in the range of 10 to 100 nm. Since the polishing portion is provided, an excellent sharpness can be obtained regardless of the diamond coating while ensuring a predetermined cutting edge strength. That is, since polishing by ion beam irradiation is non-contact, a polishing load does not act on the cutting edge, and sharp polishing can be performed until the cutting edge width Φ becomes 100 nm or less. This makes diamond coating possible even for glass cutting tools, paper cutting tools, and CFRP (carbon fiber reinforced plastic) processing tools that could not be applied in the past because of the roundness caused by the diamond coating. , Durability can be greatly improved. In addition, since polishing is performed in a non-contact manner, for example, even if the blade portion is long or has a curved shape such as an arc shape, it can be uniformly polished with a certain machining allowance. The target shape can be polished with higher accuracy than polishing.

The second invention is a case where a blade portion having a predetermined blade edge angle θa having a triangular cross section is provided, and the diamond coating is polished by an ion beam, so that the blade edge angle θ is larger than the blade edge angle θa at the tip portion of the blade portion. ₁ and a sharpened tip polishing part is provided so that the tip edge width Φ is in the range of 10 to 100 nm, so that an excellent sharpness can be obtained regardless of diamond coating while ensuring a predetermined edge strength. The same effects as the first invention can be obtained. In addition, since the tip polishing portion has a cutting edge angle θ ₁ larger than the original cutting edge angle θa, it is possible to sharpen the tip by locally polishing only the tip portion of the cutting edge, and the machining allowance is as much as possible The polishing cost can be reduced by reducing the amount.

According to a third aspect of the present invention, there is provided an intermediate polishing portion that is polished so as to have a cutting edge angle θ ₂ that is larger than the cutting edge angle θa and smaller than the cutting edge angle θ _1, and the cutting edge is located on the tip side of the intermediate polishing section. Since the tip polishing portion having the angle θ ₁ is provided, for example, when the polishing is performed by irradiating with a certain cutting edge angle θ ₁ or θ ₂ by ion beam irradiation until the cutting edge width Φ is in the range of 10 to 100 nm. In comparison with the above, the allowance for removing the diamond coating on the blade edge portion is reduced, and the decrease in strength and durability due to polishing is suppressed. The intermediate polishing portion is also preferably polished by ion beam irradiation, but can also be polished by mechanical polishing with a diamond grindstone or the like.

  The fourth invention relates to a scribing wheel for scratching the glass by cutting the glass at the tip of the blade when cutting the glass. The scribing wheel is provided with a blade on the entire circumference of the disk shape. By irradiating the outer periphery with an ion beam while polishing it, it is possible to uniformly polish with a certain machining allowance over the entire circumference, and the blade edge width Φ is almost constant over the entire circumference. Can be formed. That is, in the case of a circular diamond-coated tool having a blade portion provided on one circumference like a scribing wheel, the outer peripheral blade portion is polished while rotating the diamond-coated tool around the axis. However, in the case of mechanical polishing with a diamond grindstone, it is inevitable that the distance to the grindstone changes due to the eccentricity of the diamond-coated tool, and it is practical to perform polishing with a uniform allowance on the entire circumference in the micron order. Is impossible.

The fifth aspect of the invention relates to a manufacturing method for manufacturing the diamond-coated tool of the third aspect of the invention, and the same effects as those of the third aspect of the invention can be obtained. Further, the intermediate polishing portion having a cutting edge angle θ ₂ larger than the cutting edge angle θa, and the sharpening so that the cutting edge angle θ ₁ is larger than the cutting edge angle θ ₂ and the cutting edge width Φ of the tip is in the range of 10 to 100 nm. Since all the tip polishing parts are polished by ion beam irradiation, the intermediate polishing part can be polished to a target shape with higher accuracy than when the intermediate polishing part is polished by mechanical polishing with a grindstone, etc. A series of polishing operations can be easily performed simply by changing the irradiation conditions such as the irradiation angle.

  In the sixth invention, since the intermediate polishing portion and the tip polishing portion are formed by adjusting the processing angle α by changing the acceleration voltage of the ion beam, a series of polishing operations can be performed more easily in succession.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the scribing wheel (diamond coating tool) which is one Example of this invention, (a) is the front view seen from the direction orthogonal to an axial center, (b) is the side view seen from the right direction of (a). FIG. 4C is an enlarged cross-sectional view of the IC part in FIG. It is a figure explaining the manufacturing process of the scribing wheel of FIG. FIG. 3 is a diagram for specifically explaining a first polishing step and a second polishing step in FIG. 2. It is an electron micrograph of the front-end | tip of the blade part of the scribing wheel of FIG. It is a figure explaining the usage method at the time of cut | disconnecting the optical fiber of a tape core wire using the scribing wheel of FIG. 1, (a) is a perspective view of a 4 core type tape core wire, (b) is the tape core wire. It is a figure which shows the method of attaching a wrinkle to an optical fiber with a scribing wheel. It is a figure explaining the result of the durability test in the case of using a conventional product, the present invention products 1 to 3, and comparative products 1 and 2 to cut an optical fiber with a scissors. It is a figure explaining the other Example of this invention, and all are the cross-sectional enlarged views of the front-end | tip part of the blade part corresponded in FIG.1 (c). FIG. 6 is a diagram for explaining still another embodiment of the present invention, and each is an enlarged cross-sectional view of the tip portion of the blade portion corresponding to FIG. 1 (c). It is a figure explaining another Example of this invention, and is a cross-sectional enlarged view of the front-end | tip part of the blade part corresponded to FIG.1 (c). FIG. 6 is a diagram for explaining still another embodiment of the present invention, and (a) to (c) are perspective views of a diamond-coated tool for cutting glass.

  The diamond-coated tool of the present invention is preferably applied to a glass cutting tool such as a scribing wheel, but can also be applied to a paper cutting tool, a CFRP processing tool, or a cutting tool such as a cutting tool. For the coating of the diamond film, a CVD method such as a microwave plasma CVD method, a hot filament CVD method, or a high frequency plasma CVD method is preferably used, but other coating techniques such as an ion beam method can also be adopted. The diamond coating is polycrystalline, and is coated with a substantially constant film thickness within a range of, for example, 10 to 20 μm. When the diamond coating has a triangular section with a cutting edge angle θa as in the second invention, the tool base material has substantially the same cutting edge. It has a triangular cross section with an angle θa. In order to ensure adhesion (adhesion strength) to the tool base material made of cemented carbide or ceramics, the surface of the tool base material is subjected to pretreatment such as acid treatment or a predetermined underlayer is provided under the diamond coating. It is also possible to do.

For example, the blade portion of the diamond-coated tool is suitably a triangular one having a predetermined cutting edge angle θa as in the second invention. However, in the practice of the first invention, the shape of the tool base material and the diamond coating itself is particularly There is no limitation, and the cross section of the blade portion may be oval or oval, and the surface of the diamond coating is polished by irradiation with an ion beam, so that the blade width Φ is in the range of 10 to 100 nm. It is only necessary to provide a sharpened tip polishing portion having a triangular cross section. The tip polishing portion does not necessarily have a triangular shape, and has a concave shape in which two sides intersecting at the tip of the blade portion are recessed inward, or a convex shape that bulges outward. Also good. The tip polishing portion of the second and fifth inventions is the same, and the blade edge angle θ ₁ may be constant, but may be continuously changed in an angle range larger than the blade edge angle θa. The same applies to the intermediate polishing portions of the third and fifth inventions, and the cutting edge angle θ ₂ may be constant, but continuously changes in an angle range larger than the cutting edge angle θa and smaller than the cutting edge angle θ _1. You may let them. However, in the sixth invention, the intermediate polishing portion is provided at a substantially constant included angle theta _2, the tip grinding unit is provided at a substantially constant included angle theta _1.

As the ion beam, inert gas ions such as argon and xenon are preferably used, but other gas ions such as oxygen ions can also be used, and gallium (Ga ⁺ ) emitted from the target by arc discharge or the like. It is also possible to use predetermined metal ions. Such an ion beam is, for example, a diamond using an ion beam and an electron beam disclosed in JP-A-10-172502, JP-A-2002-187793, or “Mechanical Research Vol. 55 No. 8” (2003). It can be generated using the technique described in "Microfabrication".

  If the cutting edge width Φ is smaller than 10 nm, the cutting edge becomes brittle and chipping easily occurs. On the other hand, if it is larger than 100 nm, the sharpness is deteriorated, so that it is set to 100 nm or less. A range of 20 to 80 nm is more desirable. When the blade portion is observed with an electron microscope from the blade edge side, the edge line portion of the blade edge looks like a white streak. Therefore, the width dimension of the white streak can be measured as the blade width Φ. Further, from the electron micrograph of a cross section cut perpendicularly to the blade edge, the width dimension of the apex portion having the cutting edge roundness or the like may be measured as the blade edge width Φ. When the blade portion is provided with a predetermined length, the blade width Φ has a variation in the longitudinal direction of the blade portion, and therefore the average value may be within the range of 10 to 100 nm.

In the second invention, the tip grinding portion is provided with a blade edge angle θ ₁ larger than the blade edge angle θa with respect to the blade section of the triangular section of the blade edge angle θa, but the blade edge angle θ ₁ is 10 more than the blade edge angle θa. An angle larger than ° is desirable. When the intermediate polishing portion is provided as in the third aspect of the invention, the edge angle θ ₂ of the intermediate polishing portion is made, for example, 10 ° or more larger than the blade edge angle θa, and the edge angle θ ₁ of the tip polishing portion is set to the intermediate polishing portion. It is desirable that the edge angle θ ₂ be larger by 10 ° or more.

  The fourth invention relates to a scribing wheel having a circular blade portion facing outward on the outer peripheral portion, but having a straight blade portion, and other glass cutting members having a blade portion having a conical shape, a pyramid shape or the like. It can also be applied to tools. The scribing wheel can be scratched with a predetermined depth of cut by pressing the outer peripheral blade against the glass while rotating around the axis, but it moves relative to the glass without rotation. You can scratch it to make it wrinkled, or just press it against the glass.

In the sixth aspect of the invention, the machining angle α is adjusted according to the cutting edge angles θ ₁ and θ ₂ by changing the acceleration voltage of the ion beam, but other irradiation conditions such as the irradiation angle of the ion beam are further set. It is also possible to adjust the machining angle α by changing. In carrying out the fifth invention, it is also possible to adjust the processing angle α only by changing other irradiation conditions such as the irradiation angle without changing the acceleration voltage of the ion beam. The intermediate polishing portion of the third invention may be polished by a polishing method other than polishing by ion beam irradiation, such as mechanical polishing with a diamond grindstone.

  In the sixth aspect of the invention, the intermediate polishing portion and the tip polishing portion are formed so that the both side surfaces of the blade portion are symmetrically inclined with respect to the blade portion center plane S. By irradiating the side surfaces on both sides separately with the ion beam and polishing, an intermediate polishing portion and a tip polishing portion whose both side surfaces are inclined asymmetrically or symmetrically with respect to the blade center surface S are formed. You can also. When having a long blade part such as a straight blade part or a circular blade part, in order to make the blade edge width Φ within the range of 10 to 100 nm, for example, each side surface of the blade part is irradiated with an ion beam. It is only necessary to polish both sides. In the case of having a cone-shaped or pyramid-shaped blade portion, it may be polished by irradiating the entire circumference with an ion beam, for example, by rotating it around an axis.

  The diamond-coated tool has a polishing range of the tip polishing portion so that, for example, only the tip polishing portion is involved in processing, but depending on the type of tool, the intermediate polishing portion or ion beam polishing is performed. The part which does not exist may be involved in processing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1A and 1B are diagrams for explaining a scribing wheel 10 according to an embodiment of the present invention. FIG. 1A is a front view seen from the outer peripheral side perpendicular to the axis, and FIG. 1B is a right direction of FIG. (C) is an enlarged cross-sectional view of the IC part in (a). The scribing wheel 10 is formed by coating a polycrystalline diamond film 14 on the surface of a tool base material 12 made of a cemented carbide, and has a disc shape as a whole, and the outer periphery of the disc shape. A blade portion 16 is provided so as to protrude toward the outer peripheral side on the entire circumference of the shaft, and is rotatable around the axis via a support shaft 18 provided on a disk-shaped axis. The scribing wheel 10 corresponds to a diamond-coated tool, the outer diameter of the blade portion 16 to the cutting edge is about 20 mm, the plate thickness is about 5 mm, and the film thickness of the diamond coating 14 is about 20 μm.

In the cross section including the axis shown in (c), the blade portion 16 has a triangular shape in which the blade tip 20 at the tip protrudes toward the outer peripheral side (upward in FIG. 1 (c)). It is configured symmetrically with respect to a right-angled blade center plane S (a plane perpendicular to the paper surface of FIG. 1 (c)). The entire blade edge angle θa of the blade portion 16 is about 70 ° in the present embodiment, and the diamond coating 14 is coated with a substantially constant film thickness. The section has a triangular shape with a cutting edge angle of 70 °. The blade portion 16 is also irradiated with an ion beam on the surface of the diamond coating 14 and both sides are polished symmetrically, so that the tip portion of the blade portion 16 has a substantially constant blade edge larger than the blade edge angle θa. A triangular intermediate polishing portion 22 that is symmetrically inclined with respect to the blade center plane S at an angle θ ₂ is provided, and is substantially constant at a tip side of the intermediate polishing portion 22 that is larger than the blade edge angle θ ₂ . A triangular tip polishing portion 24 is provided that is symmetrically inclined with respect to the blade center plane S at the blade edge angle θ ₁ and is sharpened so that the blade tip width Φ is within the range of 10 to 100 nm. Yes. The intermediate polishing portion 22 includes a pair of polishing surfaces 22a and 22b symmetrically with the blade center surface S interposed therebetween, and the tip polishing portion 24 symmetrically includes a pair of polishing surfaces with the blade center surface S interposed therebetween. 24a and 24b are provided.

In the present embodiment, as shown in the invention 2 in FIG. 6, the cutting edge width Φ≈30 nm at the tip, the cutting edge angle θ ₂ ≈80 ° of the intermediate polishing portion 22, and the cutting edge angle θ ₁ ≈100 ° of the polishing tip 24. The film thickness d of the diamond coating 14 at the blade edge 20 is d≈14.3 μm. FIG. 4 is an electron micrograph of the tip of the blade portion 16, and the central white stripe-like portion is the ridge line portion of the blade edge 20, and the width dimension of this white stripe is the blade edge width Φ. The value is about 30 nm. The cutting edge angles θ ₁ and θ ₂ can be measured from an electron micrograph of a cross section cut perpendicular to the cutting edge 20, and the average values measured at several places are θ ₁ ≈100 ° and θ ₂ ≈80. °. The film thickness d of the diamond coating 14 on the blade edge 20 is also measured from an electron micrograph of a cross section cut perpendicularly to the blade edge 20, and the average value at some locations is about 14.3 μm.

  FIG. 2 is a view for explaining a method of manufacturing the scribing wheel 10 configured as described above. First, a disk-shaped tool base material in which a blade portion 16 is provided at the outer peripheral portion with a blade edge angle θa protruding toward the outer peripheral side. 12 is prepared, and at least the surface of the blade portion 16 of the tool base 12 is coated with a polycrystalline diamond film 14 to a thickness of about 20 μm by a microwave plasma CVD apparatus or the like. Prior to diamond coating, the surface of the tool base 12 may be subjected to pretreatment such as acid treatment or a predetermined underlayer so as to obtain predetermined adhesion (adhesion strength). In FIG. 1C, the alternate long and short dash line is the state in which the diamond coating 14 is still coated, and the tip of the blade portion 16 is rounded with a radius of about 15 μm by the coating of the diamond coating 14.

  Subsequently, by irradiating the tip portion of the blade portion 16 provided with the diamond coating 14 with an ion beam, the first polishing process is performed to form the intermediate polishing portion 22, and the tip of the intermediate polishing portion 22 is further formed. By irradiating the portion with an ion beam, the second polishing process is performed to form the tip polishing portion 24. The two-dot chain line in FIG. 1 (c) is a state where the first polishing process is performed and the intermediate polishing part 22 is formed, and the tip of the blade part 16 at this stage is not a diamond coating indicated by the one-dot chain line. Although it is small, it is still rounded with a relatively large radius, and as shown by the solid line, the tip is sharpened until the tip width Φ reaches about 30 nm.

In the first polishing process and the second polishing process, for example, as shown in FIG. 3 (a), the diamond-coated scribing wheel 10 is rotated about 3 rotations / minute around the axis through the support shaft 18. Irradiation with an Ar ⁺ (argon) ion beam using the ion generator 30 is performed substantially perpendicularly to the blade 16 on the outer peripheral portion, that is, perpendicular to the axis of the scribing wheel 10 while rotating at a speed. To do. The beam diameter (diameter) of the Ar ⁺ ion beam is about 20 mm. Then, the processed surface to be polished by irradiation with the Ar ⁺ ion beam is polished so as to be inclined by a processing angle α from a direction perpendicular to the irradiation direction as shown in (b). Changes according to the acceleration voltage of the Ar ⁺ ion beam as shown in (c). In this example, in the first polishing process, the acceleration voltage is set to about 3000 eV and irradiation with an argon ion beam is performed so that the polishing process is performed at a processing angle α≈50 ° and the cutting edge angle θ ₂ ≈80 ° is intermediate. A polishing portion 22 is formed. In the second polishing process, the acceleration voltage is set to about 1000 eV and irradiation with an Ar ⁺ ion beam is performed so that the polishing process is performed at a processing angle α≈40 °, and the tip polishing portion is at a cutting edge angle θ ₁ ≈100 °. 24 is formed. The current density is 0.1 to 2.0 × 3 mA / cm ² and the gas flow rate is about 0.50 to 2.0 SCCM. The polishing amount (removal allowance) can be adjusted by the polishing time. In this embodiment, the polishing time is about 1 hour in both the first polishing process and the second polishing process.

  And the scribing wheel 10 comprised as mentioned above is used suitably, for example, when cut | disconnecting the optical fiber (material is quartz glass) 42 etc. of the tape core wire 40, as shown in FIG. FIG. 5A is a perspective view showing an example of the tape core 40. The tape core 40 is a four-core type, and four optical fibers 42 are embedded in parallel to each other at a constant interval. The diameter of the optical fiber 42 is about 0.125 mm, and each is coated with a synthetic resin material to form a strand 44 having a diameter of about 0.25 mm. Four strands 44 are arranged in parallel and further UV-curable synthetic resin material. Thus, the tape core wire 40 is formed by integration. FIG. 5B shows a state in which the optical fiber 42 is scratched by the scribing wheel 10 in order to cut the optical fiber 42, and a cover such as a synthetic resin is peeled off from the optical fiber 42 by a remover. Each of the four optical fibers 42 is positioned in the groove, and the scribing wheel 10 is moved on the optical fiber 42 without rotating around the axis, and a scissors are cut at a cutting depth of about 0.01 mm. That is, by cutting the cutting edge 20 of the blade portion 16 into the optical fiber 42 at a depth of about 10 μm, a V-shaped groove corresponding to the tip polishing portion 24 is formed on the outer peripheral surface of the optical fiber 42. The tip polishing portion 24 is provided in a sufficient range in which a wrinkle having a predetermined depth can be attached only by the tip polishing portion 24 as described above.

FIG. 6 is a diagram for explaining the results of a durability test in the case where the optical fiber 42 is cut as described above using the conventional product, the present invention products 1 to 3 and the comparative products 1 and 2 as described above. . The conventional product is a case where the tool base material 12 of the above-described embodiment is used as it is, and the cutting edge width Φ is about 500 nm. Since the cemented carbide is coarse, it is difficult to make the edge width Φ smaller than this. Inventive product 1 is a case where polishing is performed by irradiation with an Ar ⁺ ion beam until the cutting edge width Φ is about 30 nm with the same cutting edge angle ≈80 ° as that of the intermediate polishing portion 22, and the film thickness d of the cutting edge 20 ≈8.2 μm. become. The invention product 2 is the same as the scribing wheel 10 of the above embodiment. Inventive product 3 is a case where the cutting edge width Φ≈80 nm of the tip polishing portion 24 is larger than that of the above embodiment, and the machining allowance of the diamond coating 14 is reduced. Therefore, the polishing time is shortened and the film thickness d of the cutting edge 20 is reduced. Become thicker. The comparative product 1 is a case where the cutting edge width Φ≈150 nm of the tip polishing portion 24 exceeds 100 nm, and the film thickness d of the cutting edge 20 is approximately 15.6 μm. The comparative product 2 is the one in which the diamond film 14 is still coated in the above example and is not subjected to the polishing treatment by the ion beam irradiation, and the tip of the blade portion 16 is shown by a one-dot chain line in FIG. 1 (c). And the film thickness d of the blade edge 20 is approximately 20 μm.

  The “endurance number” in FIG. 6 is the number of processing until the optical fiber 42 cannot be lightly folded by hand. When reaching the endurance limit, the scribing wheel 10 is rotated to shift the processing site, and until the endurance limit is reached. Although it repeats using, it is the number of processing until it reaches the endurance limit in one processing part about this invention products 1-3 and comparative product 1. The conventional product has a predetermined current state that can be brazed with a single scribing wheel 10 when brazing is performed at a total of 12 machining sites by changing the machining site with a predetermined number of treatments. Is the number of settings.

  From the results of FIG. 6, according to the products 1 to 3 of the present invention that were coated with the diamond coating 14 and polished so that the blade edge width Φ was within the range of 10 to 100 nm by ion beam irradiation, compared with the conventional products. It is clear that the durability is greatly improved. In particular, when the polishing is performed in two stages as in Invention Product 2, the film thickness d of the blade edge 20 is increased even when the cutting edge width Φ≈30 nm is the same as that of Invention Product 1 polished in one stage, and the durability number is increased. Becomes about 1.5 times. The comparative product 1 coated with the diamond film 14 also has improved durability as compared with the conventional product, but the number of durability is less than that of the products 1 to 3 of the present invention, and considering the polishing treatment with diamond coating or ion beam. Unsatisfactory in terms of cost effectiveness. The comparative product 2 had a large roundness at the tip of the blade portion 16 and could not be wrinkled to such an extent that the optical fiber 42 could be cut.

As described above, according to the scribing wheel 10 of this embodiment, the diamond coating 14 is polished by the ion beam, so that the tip portion of the blade portion 16 has a blade edge angle θ ₁ larger than the original blade edge angle θa and the blade edge width. Since the tip polished portion 24 having a triangular cross section sharpened so that Φ is in the range of 10 to 100 nm is provided, an excellent sharpness can be obtained regardless of the diamond coating while ensuring a predetermined cutting edge strength. become. That is, since polishing by ion beam irradiation is non-contact, a polishing load does not act on the cutting edge 20 and sharp polishing can be performed until the cutting edge width Φ becomes 100 nm or less. As a result, the diamond coating 14 can be coated even on the scribing wheel 10 that could not be applied in the past due to the roundness caused by the diamond coating, and the durability can be greatly improved.

  Further, since the scribing wheel 10 provided with the blade portion 14 on the entire circumference of the disk shape is rotated around the axis while being irradiated with an ion beam on the outer circumference, the polishing is performed in a non-contact manner, so that the entire circumference is constant. The cutting edge 16 can be polished uniformly, and the cutting edge width Φ can be formed with high accuracy over the entire circumference. That is, when the blade portion 16 is provided on one circumference like the scribing wheel 10, polishing is performed while rotating the scribing wheel 10 around the axis, but in the case of mechanical polishing with a diamond grindstone, scribing is performed. It is unavoidable that the distance between the wheel 10 and the grindstone changes due to the eccentricity of the wheel 10, and it is practically impossible to perform polishing with a uniform machining allowance on the entire circumference in the order of microns.

In addition, since the tip polishing portion 24 has a blade edge angle θ ₁ that is larger than the original blade edge angle θa, it is possible to sharpen the tip by locally polishing only the tip portion of the blade portion 16, and the machining allowance is reduced. The polishing cost can be reduced as much as possible.

Further, in this embodiment, an intermediate polishing portion 22 is provided which is polished so as to have a cutting edge angle θ ₂ which is larger than the cutting edge angle θa and smaller than the cutting edge angle θ _1. 6 is provided with a tip polishing portion 24 having a cutting edge angle θ ₁ , and as shown in the product 1 of FIG. 6, the polishing is performed at a constant cutting edge angle until the cutting edge width Φ is in the range of 10 to 100 nm. In comparison with this, the amount of polishing (removal allowance) of the diamond coating 14 at the blade edge 20 is reduced, the film thickness d is increased, and the decrease in strength and durability due to polishing is suppressed.

Further, in the present embodiment, the intermediate polishing portion 22 having a cutting edge angle θ ₂ larger than the cutting edge angle θa, and the cutting edge angle θ ₁ larger than the cutting edge angle θ ₂ and the cutting edge width Φ of the tip is in the range of 10 to 100 nm. Since each of the sharpened tip polishing portions 24 is polished by ion beam irradiation, the intermediate polishing portion 22 is polished to a target shape with higher accuracy than when the intermediate polishing portion 22 is polished by mechanical polishing with a grindstone or the like. In addition, a series of polishing operations can be easily performed continuously only by changing the acceleration voltage.

  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.

7A has a substantially constant cutting edge angle θ ₁ larger than the cutting edge angle θa without providing an intermediate polishing section in the scribing wheel 10 and has a cutting edge width Φ of 10 to 100 nm. In the case where the tip polishing portion 52 sharpened so as to be within the range is provided symmetrically with respect to the blade center surface S, it substantially corresponds to the product 1 of FIG. The tip polishing portion 52 includes a pair of polishing surfaces 52a and 52b symmetrically across the blade center surface S.

  The blade portion 60 of FIG. 7B is a case where the tip polishing portion 62 is provided asymmetrically with respect to the blade center surface S as compared with the blade portion 50 of FIG. It is located at a portion offset from the blade center plane S by a predetermined dimension. The tip polishing portion 62 includes a pair of polishing surfaces 62a and 62b that are asymmetric with respect to the blade center surface S on both sides of the blade portion 60. These polishing surfaces 62a and 62b are separately provided under different irradiation conditions. It can be formed by irradiating with an ion beam and polishing.

The blade portion 70 in FIG. 8A is a case where the blade edge angle θ ₁ continuously changes in an angle range larger than the blade edge angle θa as compared with the blade portion 50 in FIG. The pair of polishing surfaces 72a and 72b of the tip polishing portion 72 has a concave shape that is recessed so as to curve inward. The blade edge angle θ ₁ is smaller toward the tip side, and can be formed by changing the ion beam irradiation condition continuously or stepwise. It is also possible to change the cutting edge angle θ _{1 including an} angle smaller than the cutting edge angle θa.

8B, the pair of polishing surfaces 76a and 76b of the tip polishing portion 76 are smoothly curved outward as compared with the blade portion 70 of FIG. 8A. It has a bulging convex shape. The blade edge angle θ ₁ increases toward the tip side, and can be formed by changing ion beam irradiation conditions continuously or stepwise.

The diamond-coated tool 80 of FIG. 9 is a case where the cross section of the tool base material 82 is elliptical and the surface thereof is coated with a diamond coating 84 with a substantially constant film thickness. A blade portion 86 is provided on the blade. Then, by irradiating the tip portion of the blade portion 86 with an ion beam and polishing, a cross section sharpened so that the tip edge angle θ ₁ and the tip edge width Φ is in the range of 10 to 100 nm. Triangular tip grinding | polishing part 88 is provided symmetrically with respect to the blade-part center plane S, for example, is used as a glass cutting tool which cuts a glass with a wrinkle. The tip polishing portion 88 includes a pair of polishing surfaces 88a and 88b symmetrically across the blade center surface S. Also in this example, the diamond coating can provide excellent durability and is sharpened so that the blade width Φ is in the range of 10 to 100 nm by polishing by ion beam irradiation. In spite of this, it is possible to obtain the same effect as in the above-described embodiment, for example, an excellent sharpness can be obtained. As shown in the embodiment of FIG. 1, an intermediate polishing portion having a cutting edge angle θ ₂ smaller than the cutting edge angle θ ₁ is provided on the base side of the tip polishing section 88 (lower side in FIG. 9) prior to the tip polishing section 88. It is also possible to provide it.

  10 (a) is a diamond-coated tool having a straight blade portion 90 having a triangular section, (b) is a diamond-coated tool having a conical blade portion 92, and (c) is a pyramid-shaped blade portion. 94 is a diamond-coated tool, and any of them is a glass-cutting tool in which the tips of the blade portions 90, 92, 94 are pressed against the glass plate and scratched. Also for such a diamond-coated tool, the blade portions 90, 92, and 94 are polished by irradiating with an ion beam as in the above embodiments, and an intermediate polishing portion and a tip polishing portion are provided, and the blade edge width Φ is 10 to 100 nm. By sharpening the blade edge so that it falls within the range, an excellent sharpness can be obtained regardless of the diamond coating.

  As mentioned above, although the Example of this invention was described in detail based on drawing, these are one embodiment to the last, and 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: Scribing wheel (diamond-coated tool) 12, 82: Tool base material 14, 84: Diamond coating 16, 50, 60, 70, 74, 86, 90, 92, 94: Blade portion 22: Intermediate polishing portion 24, 52 , 62, 72, 76, 88: Tip polishing portion 80: Diamond coated tool S: Blade center surface θa, θ ₁ , θ ₂ : Blade angle Φ: Blade width

Claims (6)

In a diamond-coated tool in which a predetermined blade portion is formed by coating a diamond coating on the surface of a tool base material made of cemented carbide or ceramics,
The surface of the diamond coating provided on the blade portion is irradiated with an ion beam and polished, so that the tip of the blade portion is sharpened so that the blade tip width Φ is in the range of 10 to 100 nm. A diamond-coated tool provided with a shaped tip polishing portion. In a diamond-coated tool in which a diamond coating is formed on a surface of a tool base material made of cemented carbide or ceramics to form a triangular triangular blade section having a predetermined cutting edge angle θa,
When the surface of the diamond coating provided on the blade portion is irradiated with an ion beam and polished, the tip portion of the blade portion has a blade edge angle θ ₁ larger than the blade edge angle θa and a tip edge width Φ. A diamond-coated tool characterized in that a sharpened tip polishing portion is provided so as to be within a range of 10 to 100 nm. The diamond coating provided on the blade portion is provided with an intermediate polishing portion polished to have a blade edge angle θ ₂ that is larger than the blade edge angle θa and smaller than the blade edge angle θ _1. The diamond-coated tool according to claim 2, wherein the tip polishing portion is provided on the tip side of the polishing portion. The diamond-coated tool has a disc shape as a whole, and the blade portion is provided so as to protrude toward the outer peripheral side on the entire circumference of the disc-shaped outer peripheral portion. The diamond-coated tool according to any one of claims 1 to 3, which is a scribing wheel for scoring the glass at the tip of the blade portion. The present invention relates to a diamond coated tool in which a diamond coating is coated on the surface of a tool base material made of cemented carbide or ceramics to form a triangular section with a predetermined cutting edge angle θa, and the diamond coating on the cutting section is polished. A manufacturing method for sharpening,
By irradiating the surface of the diamond coating provided on the blade portion with an ion beam and polishing, an intermediate polishing portion having a blade edge angle θ ₂ larger than the blade edge angle θa is formed at the tip portion of the blade portion. 1 polishing step,
By changing the irradiation condition of the ion beam and irradiating the surface of the intermediate polishing portion for further polishing, the tip portion of the intermediate polishing portion has a cutting edge angle θ ₁ larger than the cutting edge angle θ ₂ and the tip of the tip. A second polishing step of forming a tip polishing portion sharpened so that the blade width Φ is in the range of 10 to 100 nm;
A method for producing a diamond-coated tool characterized by comprising: By changing the acceleration voltage of the ion beam and adjusting the processing angle α of the polishing by irradiation of the ion beam, the cutting edge angle θ ₂ is symmetrical with respect to the blade center plane S in the first polishing step. The intermediate polishing portion that is inclined is formed, and the tip polishing portion that is symmetrically inclined at the blade edge angle θ ₁ with respect to the blade center surface S is formed in the second polishing step. A method for producing a diamond-coated tool as described in 1.