JP2005238349A - Method of manufacturing dry processing tool and dry processing drill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a dry processing tool and a dry processing drill further inexpensive in maintenance cost, by sufficiently restraining welding of cutting chips to a rake surface and a blade groove, in dry processing. <P>SOLUTION: This dry processing drill 10 with a diamond coating film forms the diamond coating film 17 in a processing blade part 16. Here, the diamond coating film 17 is formed on the rake surface 14 and an outer peripheral surface 16 for forming a blade surface among the processing blade part 16, and the diamond coating film 17 is not formed on a thinning surface 11, a flank 12 and a third surface 13. Thus, the thinning surface 11, the flank 12 and the third surface 13 can be easily repolished. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a dry machining tool and a dry machining drill manufacturing method.

  In recent years, dry machining technology has been actively researched and developed as an environmental conservation initiative in the machining field. Here, the dry processing technique is such that the cutting oil is not used at the time of processing, or a small amount of mist is used as the cutting oil. Thus, it can be said that it is an environment-friendly processing technique because the amount of cutting oil used is very small or very small in dry processing. In addition, what uses no cutting oil is called complete dry processing, and what uses a trace amount mist is called semi-dry processing. In the present specification, the dry processing includes the complete dry processing and the semi-dry processing.

  However, when an aluminum material or the like is drilled, cutting scraps of the aluminum material generated by the drilling are welded to the rake face and the blade groove of the drill, and the rake face and the blade groove are likely to be blocked by the cutting waste. If the rake face or blade groove of the drill is clogged with cutting waste, the drill may break. Therefore, it is necessary to suppress the welding of cutting waste to the rake face or blade groove as much as possible.

As a technique for suppressing welding of cutting scraps to such a rake face or blade groove, for example, as disclosed in Japanese Patent Application Laid-Open No. 2002-79406 (the following Patent Document 1), the entire processing blade portion of the drill is superfluous. There is a technique of covering with a microcrystalline diamond film. In this way, by coating the entire drilling blade with a diamond coating, the rake face and blade groove of the drill and the cutting scrap of the workpiece are prevented from being welded. Cutting clogging can be suppressed. Thereby, high-efficiency machining with complete dryness can be realized.
Japanese Patent Laid-Open No. 2002-079406

  Here, when the sharpness of the drill-like tool is inferior from the initial stage of use, it is necessary to re-grind the machining blade. This re-grinding of the machining blade is caused by the thinning surface or flank of the drilling blade. This is done for the face. However, in the prior art as described above, a diamond film is also formed on the thinning surface, the flank surface, and the third surface in addition to the rake surface and the blade groove of the machining blade portion. Since the diamond film has a very high hardness, it is difficult to re-polish the thinning surface, the flank surface and the third surface when re-polishing the tool. Therefore, when the processing accuracy of the tool is lowered, it is necessary to replace the processing tool of the tool, and there is a problem that the cost of the tool becomes very expensive.

  The present invention has been made in view of the above-described problems. In dry processing, the present invention is intended for dry processing that sufficiently suppresses welding of cutting swarf to a rake face and a blade groove and has lower maintenance costs. It is an object to provide a tool.

  In order to solve the above problems, a first aspect of the present invention is a dry processing tool in which a diamond film is formed on the surface of a processing blade portion, and the polishing blade portion needs to be re-polished. It is a dry processing tool characterized in that the diamond film is not formed on the blade portion. In the present specification, the processing blade portion does not directly indicate only a portion for processing a workpiece. That is, the processing blade portion includes a portion that does not directly contact the base material of the workpiece and is not involved in the processing itself. Specifically, the processing blade portion may have a blade surface that directly processes the workpiece and a flank that allows the blade surface to escape from the workpiece. In this case, the flank face of the machining blade portion does not directly affect the machining of the workpiece.

  In the present invention, the dry processing tool is a general term for tools used in semi-dry processing or complete dry processing. Specific examples of the tool shape include a drill, a tap, a reamer, and an end mill.

  Further, a second aspect of the present invention is the dry processing tool according to the first aspect of the present invention, wherein the dry machining tool is a drill-like tool having at least a flank on the machining blade portion, and the diamond coating is formed on the flank. It can not be. Here, the flank of the drill-like tool is the cutting edge of the drill-like tool, considering the strength of the blade and the friction between the blade and the workpiece. It is a part formed in the processing blade part in order to keep the angle appropriate.

  Further, according to a third aspect of the present invention, in the first aspect of the present invention, a third surface is formed on the processing blade portion, and the diamond film is not formed on the third surface. it can. Here, the third surface is a portion formed on the machining blade portion so that the machining blade portion and the workpiece do not interfere when the machining blade portion moves relative to the workpiece.

  Furthermore, a fourth aspect of the present invention is that in the second or third aspect of the present invention, a thinning surface is formed on the processing blade portion, and the diamond film is not formed on the thinning surface. Can do. Here, the thinning surface of the drill-like tool is a portion formed at the center of the tip of the processing blade portion, and is mainly in charge of processing the workpiece in the radial direction of the processing blade portion around the thinning surface. A blade surface is formed. Furthermore, in the present invention, in the first aspect of the present invention, it is possible that no diamond film is formed on all of the flank face, the third face and the thinning face of the machining blade portion.

  The thinning surface, flank surface, and surface No. 3 are not the parts (surfaces) that are primarily responsible for machining, such as the blade surfaces, but the parts (surfaces) that greatly affect the machining efficiency of the drill-like tool. It is a portion that is re-polished when the machining efficiency of the drill-like tool decreases.

  In order to solve the above-mentioned problem, a fifth aspect of the present invention is a method for manufacturing a drill for dry processing in which a diamond film is formed on a processing blade portion for processing a workpiece, A rake face forming step for forming a rake face on a predetermined portion of the machining blade portion that is planned to be a machining blade portion, and forming the diamond film on the surface of the predetermined portion of the machining blade portion on which the rake face is formed. A dry processing drill manufacturing method comprising: a coating forming step; and a blade attaching step of forming a thinning surface or a flank from the processing blade portion planned portion on which the diamond coating is formed.

  Further, a sixth aspect of the present invention further includes a tip dropping step of cutting the tip portion of the processing blade portion planned portion on which the diamond coating is formed in the fifth aspect of the invention, and the step after the coating forming step A tip dropping process is performed, and then the blade attaching process is performed.

  According to the first aspect of the present invention, in a dry processing tool, a diamond coating is not formed on a portion of a processing blade portion for processing a workpiece that requires re-polishing. The part can be easily re-polished. Therefore, even if a tool with a diamond coating is formed, when the processing accuracy is lowered, the processing efficiency of the tool can be improved again by re-polishing the processing blade portion of the tool. Therefore, it is not necessary to replace the processing blade of the tool, and the blade cost can be reduced.

  In addition, as in the second aspect of the present invention, it is easy to re-polish the flank face of the drill-like tool by not forming a diamond film on the flank face in the machining blade portion of the drill-like tool. Furthermore, as in the third aspect of the present invention, the third surface of the drill-like tool can be easily re-polished by preventing the diamond film from being formed even on the third surface in the machining blade portion of the drill-like tool. It becomes. In addition, as in the fourth aspect of the present invention, it is easy to re-polish the thinning surface of the drill-like tool by preventing the diamond coating from being formed on the thinning surface in the machining blade portion of the drill-like tool. There are two types of drill-like tools, one with and without a thinning surface, but in the case of a drill-like tool with a thinning surface, it is necessary to re-polish this thinning surface when the machining accuracy decreases. There is. Therefore, in the case of a drill-like tool having a thinning surface, it is preferable not to form a diamond film on this thinning surface.

  Furthermore, by avoiding the formation of the diamond film on all of the thinning surface, the flank surface, and the third surface, it becomes even easier to re-polish the processing blade portion of the drill-like tool. Thereby, even if the machining efficiency of the drill-like tool is lowered, it is not necessary to replace the machining blade portion of the drill-like tool, and the cutting tool cost can be greatly reduced. In addition, when polishing the processing blade portion of the drill-like tool with the grindstone, the polishing time can be shortened, and damage to the grindstone itself can be suppressed by the diamond film formed on the surface of the processing blade portion. .

  In the fifth aspect of the present invention, a dry processing drill having a drill-like shape can be manufactured among the above-described dry processing tools according to the present invention. In the conventional dry machining drill manufacturing method, the diamond coating is formed on the entire machining blade portion because the processing blade portion of the dry machining drill is completely formed and then coated with a diamond coating. It must be done. In addition, it is not impossible to form a diamond film only on the surface where the diamond film is required in the processing blade portion, but for example, it is necessary to mask the surface where the diamond film is not required, which is very complicated. It becomes. Therefore, as in the present invention, first, only a portion (specifically, a blade surface, a rake surface, a blade groove, or the like for cutting the workpiece) is formed from the tool base material and requires machining. Before forming the entire blade part, after forming the diamond film on the planned part of the processing blade part that is to be the processing blade part, the part of the processing blade part that does not require the diamond film (specifically, the thinning surface, By forming the flank and the third surface), a dry processing drill in which a diamond coating is not formed on a portion of the processing blade that does not require a diamond coating without performing particularly complicated operations. It can be manufactured easily. In the drill-like tool, the rake face and the blade groove formed on the machining blade portion constitute the same geometric surface, and hence these are collectively referred to as a rake face.

  In the sixth aspect of the present invention, the flank face, the third face, and the thinning face can be easily formed from the planned cutting edge portion where the diamond film is formed by further including a tip dropping step. This is because the cutting edge portion where the diamond coating is not formed can be formed by cutting off the tip of the cutting edge portion where the diamond coating is formed by cutting. This is because the influence of the diamond film in the blade attaching process can be eliminated. In addition, in the tip dropping process, it is possible to make a large allowance when cutting the tip of the processing blade portion planned portion, so when cutting directly from the processing blade portion planned portion where the diamond film is formed Can be processed relatively easily.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The present invention can be applied to various cutting tools such as a drill, a tap, a cutting tool, and an end mill. Here, an embodiment in which the present invention is applied to a dry machining drill will be described. FIG. 1 shows a plan view seen from the tip side (upper side) and a plan view seen from the side of an example of a dry machining drill produced by the production method of the present invention. is there. A dry processing drill 10 shown in FIG. 1 (hereinafter simply referred to as a drill 10) is a drill with a diamond coating in which a diamond coating 17 is formed on a processing blade portion 16. In FIG. 1, the hatched portion is the portion where the diamond film 17 is formed. As described above, although the diamond coating 17 is formed on the rake face 14 and the outer peripheral face 16 of the machining blade portion 16, the thinning face 11, the flank face 12, and the third face 13 have diamonds. The film 17 is not formed.

  The diamond film 17 formed on the surface of the tool base material is a general diamond film formed by CVD. The film thickness can be 5 μm to 20 μm.

  The drill 10 as described above is suitably used for cutting nonferrous metals such as aluminum castings, aluminum alloys, copper, and copper alloys. As the tool base material before the diamond film 17 is formed, a cemented carbide can be suitably used. Other than that, tool materials, such as a cermet and a ceramic, can be employ | adopted suitably.

  Moreover, as cutting conditions, it can be used for complete dry processing using no cutting oil or semi-dry processing using a small amount of mist.

  In the drill 10 as described above, since the diamond film 17 is not formed on the thinning surface 11, the flank 12 and the third surface 13, these surfaces can be easily made when the machining efficiency of the drill 10 decreases. Can be re-polished. On the other hand, a diamond film 17 is formed on the rake face 14 for processing the workpiece, and even if the workpiece is machined by the drill 10 in dry machining with almost no use of cutting oil, the rake is raked. It is possible to prevent cutting chips from being welded to the surface 17. That is, the thinning surface 11, the flank 12, the third surface 13, and the like where the diamond film 17 is not formed are portions where welding with the cutting waste is not particularly problematic when the workpiece is processed. This is because the thinning surface 11 is formed at the center of the tip of the processing blade portion 16 and is in direct contact with the workpiece during cutting, but the processing blade portion 16 rotates and the rake surface 14 of the processing blade portion 16 is rotated. This is because when the workpiece is machined, the center of rotation is not particularly involved in the cutting process itself. Further, the flank 12 is for preventing the drill 10 and the workpiece from interfering with each other in the cutting of the workpiece, and is not a portion for directly cutting the workpiece, but is similar to the thinning surface 11. Even if the diamond film 17 is not formed, the welding of the cutting waste is not particularly problematic. The third surface 13 is the same as the flank 12.

  Hereafter, the manufacturing method of the above drills for dry processing of this invention is demonstrated using FIG. First, in step S11, outer diameter polishing is performed on a cylindrical tool base material. At this time, the tool base material can be processed in a state where the tool base material, a part of which becomes the processing blade portion 16, is held by the shank. Next, in step S12, a groove to be the rake face 14 is formed in a portion of the tool base material that is to be a machining blade portion (planning portion of the machining blade portion). This step S12 corresponds to a rake face forming step. This rake face forming step can be performed by, for example, a drill blade groove grinder.

  Next, at the stage where the groove to be the rake face 14 is formed, a diamond coating is coated on the processing blade portion of the tool base material by CVD in step S13. This step S13 corresponds to a film forming process. In forming a diamond film on the surface of the tool base material, a well-known CVD apparatus can be used, for example, a microwave plasma CVD apparatus can be used. By step S13, a diamond film 17 having a film thickness of, for example, 5 μm to 20 μm and a crystal grain size of 2 μm or less on the surface is formed on the surface of the tool base material including the rake surface 14 and the outer peripheral surface 16.

  Next, in step S14, the tip of the processing blade portion planned portion of the tool base material on which the rake face 14 and the diamond coating 17 are formed is cut off by cutting. When cutting the planned cutting edge portion of the tool base material, a method such as wire cutting or cutting with a grindstone can be employed. At this time, a cutting allowance for cutting off the tip of the tool base material can be made relatively large, and processing can be performed relatively easily rather than directly cutting from the tool base material on which the diamond coating 17 is formed. This step S14 corresponds to a tip dropping process. As a result, the diamond film 17 is not formed on at least a part of the tip of the processing blade portion planned portion.

  Next, in step S <b> 15, the flank 12, the third surface 13, and the thinning surface 11 are formed from a part of the tip where the diamond coating 17 of the processing blade portion planned portion is not formed. These surfaces can be formed by grinding the tip of the processing blade portion planned portion. Specifically, it can be performed by a known drill grinding apparatus. At this time, since the diamond film 17 is not formed at the tip of the planned cutting edge portion of the tool base material, the thinning surface 11, the flank 12 and the third surface 13 can be easily ground. Further, when grinding these surfaces, it is difficult to damage the grindstone of the drill grinding apparatus. Step S15 for forming the thinning surface 11, the flank 12 and the third surface 13 corresponds to the blade attaching step.

  In order to verify the effects of the dry machining drill 10 and the manufacturing method thereof according to the present invention as described above, the following experiment was conducted. First, as an example, a diamond film is formed on the rake face and outer peripheral surface of the machining blade portion by the method shown in FIG. 2, but the thinning surface, the flank surface, and the third surface (repolished surface) A drill as shown in FIG. 1 in which a diamond film was not formed was produced. The drill diameter is 5 mm, the tip angle is 120 °, the second clearance angle is 10 °, and the third clearance angle is 30 °. Next, as Comparative Example 1, a drill having the same shape as that of the drill 10 shown in FIG. In the drill manufacturing process, the coating (film forming process) and tip dropping process of FIG. 2 are not performed. Next, as Comparative Example 2, a drill in which a diamond film was formed on the entire processing blade as shown in the related art was produced. Specifically, as shown in FIG. 4, the outer diameter of the tool base is polished in step S21. In step S22, a groove serving as a rake face was ground in the tool base material. In step S23, unlike the example, a thinning surface, a flank surface, and a third surface (reground surface) were formed at the tip of the tool base material before forming a diamond film on the surface of the tool base material. The thinning surface, the flank surface, and the third surface were formed by the same method as in the example. Finally, in step S24, a diamond film was formed on the surface of the tool base material in a state where the machining blade portion was completely formed. The diamond film was formed by CVD similar to the example. The shape of the drill according to Comparative Example 2 is also the same shape as the drill of the example shown in FIG.

  Using the drill as described above, the working efficiency at which continuous machining was possible when an aluminum alloy casting (ADC12) was cut as a workpiece was compared between the example and the comparative example. The machining efficiency that allows continuous machining is the machining efficiency at which machining waste can be machined without welding to the machining blade portion and the rake face (blade groove). The cutting conditions are complete dry machining without using cutting oil, the machining shape is φ5 × 15, and the cutting speed is 157 m / min. The results are shown in FIG. In FIG. 3, (1) is Comparative Example 1, (2) is Comparative Example 2, and (3) is an Example. As can be seen from FIG. 3, compared to Comparative Example 1 having no diamond coating, Comparative Example 2 and Example in which the diamond coating is formed on the processing blade portion has significantly higher processing efficiency that allows continuous processing. It has improved. And when the comparative example 2 and an Example are compared, also in the Example in which the diamond membrane | film | coat is not formed in the re-polishing surface (a thinning surface, a relief surface, and the 3rd surface) of a processing blade part, the whole processing blade part It turns out that the processing efficiency similar to the comparative example 2 with which the diamond membrane | film | coat is formed is realizable. In other words, in the embodiment according to the present invention, even if the diamond film is not formed on the re-polished surfaces (thinning surface, flank surface, and third surface) that need to be re-polished, the cutting waste does not adhere to the processing blade portion. High processing efficiency can be realized.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to these. In the present embodiment, the drill-shaped tool has been described. However, welding of cutting waste becomes a problem, and the present invention can be applied to other tools having a surface that needs re-polishing such as a flank.

The figure explaining embodiment of the drill for dry processing concerning this invention. The figure explaining the manufacturing method of the drill for dry processing concerning this invention. The figure which shows the processing efficiency which can be continuously processed of an Example and a comparative example. The figure explaining the manufacturing process of the process blade part in a comparative example.

Explanation of symbols

10 Dry processing drill (Dry processing tool)
11 Thinning surface 12 Relief surface 13 3rd surface 14 Rake surface (blade surface)
15 outer peripheral surface 16 machining blade portion 17 diamond film

Claims (6)

A tool for dry machining in which a diamond film is formed on the surface of the machining blade,
The dry cutting tool, wherein the diamond coating is not formed on a blade portion that needs to be reground among the processing blade portions. 2. The dry processing tool according to claim 1, wherein the dry processing tool is a drill-shaped tool having at least a flank on the processing blade portion, and the diamond film is not formed on the flank. 3. The dry cutting tool according to claim 2, wherein a third surface is formed on the processing blade portion, and the diamond film is not formed on the third surface. The dry cutting tool according to claim 2 or 3, wherein a thinning surface is formed on the processing blade portion, and the diamond coating is not formed on the thinning surface. In a manufacturing method of a drill for dry processing in which a diamond film is formed on a processing blade portion for processing a workpiece,
A rake face forming step of forming a rake face on the processing blade part planned portion that is supposed to be the processing blade part of the tool base material;
A film forming step of forming the diamond film on the surface of the processing blade portion planned portion where the rake face is formed;
And a cutting step for forming a thinning surface or a flank surface from the predetermined portion of the processing blade portion on which the diamond film is formed. A tip dropping step of cutting a tip portion of the processing blade portion planned portion on which the diamond coating is formed, performing the tip dropping step after the coating forming step, and thereafter performing the blade attaching step. The method for manufacturing a dry machining drill according to claim 5, wherein the drill is a dry machining drill.

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