JP7473711B1

JP7473711B1 - Rotary cutting tool and manufacturing method thereof

Info

Publication number: JP7473711B1
Application number: JP2023079278A
Authority: JP
Inventors: 康友高橋; 茂平松; 亜紗日南野
Original assignee: Dijet Industrial Co Ltd
Current assignee: Dijet Industrial Co Ltd
Priority date: 2023-05-12
Filing date: 2023-05-12
Publication date: 2024-04-23
Anticipated expiration: 2043-05-12

Abstract

【課題】ねじれ溝を設けた工具本体の先端部に超高圧焼結チップを取り付け、超高圧焼結材料で構成された切れ刃をねじれ溝に沿って工具本体の軸方向に長く設けるようにする。【解決手段】一対のねじれ溝11を設けた工具本体10の先端部に超高圧焼結体20を取り付け、超高圧焼結材料で構成された切れ刃21をねじれ溝に沿って設けた回転式切削工具Xにおいて、工具本体の中心Oを通るようにして両側のねじれ溝に至る取付用ねじれ溝12を設け、超高圧焼結材料で構成された切れ刃が径方向両側に設けられた複数の超高圧焼結チップ20A～20Dを、取付用ねじれ溝内に工具本体の軸方向に複数段積層させて、超高圧焼結材料で構成された切れ刃を一対のねじれ溝に沿って形成した。【選択図】図４[Problem] An ultra-high pressure sintered tip is attached to the tip of a tool body with a helical groove, and a cutting edge made of ultra-high pressure sintered material is provided long along the helical groove in the axial direction of the tool body. [Solution] In a rotary cutting tool X in which an ultra-high pressure sintered body 20 is attached to the tip of a tool body 10 with a pair of helical grooves 11, and a cutting edge 21 made of ultra-high pressure sintered material is provided along the helical groove, a mounting helical groove 12 is provided that passes through the center O of the tool body and reaches the helical grooves on both sides, and multiple ultra-high pressure sintered tips 20A-20D with cutting edges made of ultra-high pressure sintered material provided on both radial sides are stacked in multiple stages in the mounting helical groove in the axial direction of the tool body, forming a cutting edge made of ultra-high pressure sintered material along the pair of helical grooves. [Selected Figure] Figure 4

Description

本発明は、回転して樹脂やセラミックスや非鉄金属等の被削材を切削加工するのに使用する回転式切削工具及びその製造方法に関するものである。特に、工具本体の外周に一対のねじれ溝が形成されると共に、工具本体の先端部に超高圧焼結材料で構成された切れ刃を有するねじれた超高圧焼結チップが取り付けられて、ねじれ溝に沿って超高圧焼結材料で構成された切れ刃が設けられた回転式切削工具において、超高圧焼結材料で構成された切れ刃をねじれ溝に沿って工具本体の軸方向に長く設けることができると共に、前記のような超高圧焼結材料で構成された切れ刃を有する複数の超高圧焼結チップを回転式切削工具のねじれ溝に沿って取り付けることにより、ねじれ溝のねじれ角が異なる様々な回転式切削工具においても、超高圧焼結材料で構成された切れ刃をねじれ溝に沿って簡単に設けることができるようにした点に特徴を有するものである。 The present invention relates to a rotary cutting tool that rotates to cut workpieces such as resins, ceramics, and non-ferrous metals, and a method for manufacturing the same. In particular, in a rotary cutting tool in which a pair of helical grooves are formed on the outer periphery of the tool body, and a twisted ultra-high pressure sintered tip having a cutting edge made of ultra-high pressure sintered material is attached to the tip of the tool body, and a cutting edge made of ultra-high pressure sintered material is provided along the helical grooves, the cutting edge made of ultra-high pressure sintered material can be provided long in the axial direction of the tool body along the helical grooves, and by attaching multiple ultra-high pressure sintered tips having cutting edges made of ultra-high pressure sintered material as described above along the helical grooves of the rotary cutting tool, the cutting edge made of ultra-high pressure sintered material can be easily provided along the helical grooves even in various rotary cutting tools with different helical angles of the helical grooves.

従来から、回転して被削材を切削加工するのに使用する回転式切削工具としては、エンドミルやドリルが使用されている。 Conventionally, end mills and drills have been used as rotary cutting tools that rotate to cut workpieces.

そして、このような回転式切削工具において、樹脂やセラミックス等の非鉄金属からなる被削材を切削加工するにあたって、従来から、工具本体の先端部に、ダイヤモンドや立方晶窒化硼素等の超高圧焼結材料で構成された切れ刃を有するチップを取り付けたものが示されている。 When cutting workpieces made of non-ferrous metals such as resins and ceramics, such rotary cutting tools have traditionally been equipped with a tip having a cutting edge made of ultra-high pressure sintered material such as diamond or cubic boron nitride attached to the tip of the tool body.

また、前記のような回転式切削工具としては、工具本体の先端部に切削された切り屑を排出させる複数のねじれ溝が形成されたものが使用されており、このように複数のねじれ溝が形成された工具本体の先端部に、前記の超高圧焼結材料で構成された切れ刃を有する超高圧焼結チップを取り付けるにあたって、特許文献１、２においては、各ねじれ溝のすくい面を座ぐりし、超高圧焼結材料で構成された切れ刃が形成された超高圧焼結チップを設けた台座を、前記の座ぐりした部分にろう付けするようにしたエンドミルが示されており、また特許文献３においては、各ねじれ溝のすくい面に沿って設けた取付凹部に、超高圧焼結材料で構成された切れ刃が形成された超高圧焼結チップの一部を嵌め込むようにして、超高圧焼結チップをろう付けするようにしたエンドミルが示されている。 In addition, the rotary cutting tool used has a tip portion of the tool body with multiple helical grooves that discharge the cutting chips. In attaching an ultra-high pressure sintered tip having a cutting edge made of the ultra-high pressure sintered material to the tip portion of the tool body with multiple helical grooves, Patent Documents 1 and 2 show an end mill in which the rake face of each helical groove is countersunk and a base with an ultra-high pressure sintered tip with a cutting edge made of the ultra-high pressure sintered material is brazed to the countersunk portion. Patent Document 3 shows an end mill in which an ultra-high pressure sintered tip with a cutting edge made of the ultra-high pressure sintered material is brazed by fitting a part of the ultra-high pressure sintered tip into an attachment recess provided along the rake face of each helical groove.

しかし、工具本体の径が小さく、ねじれ溝を深くすることができない回転式切削工具の場合、前記のように複数の各ねじれ溝のすくい面を座ぐりし、超高圧焼結材料で構成された切れ刃が形成された超高圧焼結チップを設けた台座を、座ぐりした部分にろう付けしたり、各ねじれ溝のすくい面に沿って取付凹部を設け、この取付凹部に、超高圧焼結材料で構成された切れ刃が形成された超高圧焼結チップの一部を嵌め込むようにして、超高圧焼結チップをろう付けする作業は非常に困難であり、さらにろう付けした超高圧焼結チップが工具本体から外れたりする等の問題もあった。 However, in the case of rotary cutting tools in which the diameter of the tool body is small and the helical flutes cannot be made deep, the work of brazing the ultra-high pressure sintered tip by countersinking the rake face of each of the multiple helical flutes as described above and brazing the base with the ultra-high pressure sintered tip with a cutting edge made of ultra-high pressure sintered material to the countersink, or by providing a mounting recess along the rake face of each helical flute and fitting a part of the ultra-high pressure sintered tip with a cutting edge made of ultra-high pressure sintered material into this mounting recess, is extremely difficult, and there are also problems such as the brazed ultra-high pressure sintered tip coming off the tool body.

また、特許文献３においては、先端切れ刃を有する超高圧焼結チップを、工具本体の先端部の径方向に設けられた取付凹部内に嵌め込むようにしてろう付けしたドリルが示されている。 Patent Document 3 also shows a drill in which an ultra-high pressure sintered tip having a cutting edge is brazed so as to be fitted into a mounting recess provided radially at the tip of the tool body.

しかし、工具本体の先端部の径方向に設けられた取付部内に、先端切れ刃を有する超高圧焼結チップを嵌め込むようにしてろう付けさせるようにした場合、工具本体の軸方向の長さが長くなった超高圧焼結チップを製造することは非常に困難であり、工具本体の先端部が鋭角になって先端切れ刃が軸方向に長くなったドリルや、工具径が大きくなって先端切れ刃の軸方向に長さも長くなったドリルを得ることは非常に困難であった。 However, when an ultra-high pressure sintered tip with a tip cutting edge is fitted and brazed into a mounting portion provided radially at the tip of the tool body, it is very difficult to manufacture an ultra-high pressure sintered tip with a long axial length of the tool body, and it is very difficult to obtain a drill with a sharp tip angle and a long axial tip cutting edge, or a drill with a large tool diameter and a long axial tip cutting edge.

また、従来においては、特許文献４に示されるように、超高圧焼結材料で構成された超高圧焼結体が軸方向に溝状に一体焼結されたチップを用い、このチップを工具本体の先端部に取り付けた後、溝状になった超高圧焼結体の部分に切れ刃を形成するようにして、軸方向に伸びた切り屑排出溝を設けるようにしたものが示されている。 Also, as shown in Patent Document 4, a conventional tool uses a tip in which an ultra-high pressure sintered body made of ultra-high pressure sintered material is sintered as a single piece into a groove in the axial direction, and after this tip is attached to the tip of the tool body, a cutting edge is formed in the grooved part of the ultra-high pressure sintered body, providing a chip discharge groove extending in the axial direction.

しかし、特許文献４に示されるものにおいては、工具本体の先端部における複数のねじれ溝に沿うようにして、超高圧焼結材料で構成された切れ刃を形成することはできなかった。 However, in the method shown in Patent Document 4, it was not possible to form a cutting edge made of ultra-high pressure sintered material along the multiple helical grooves at the tip of the tool body.

特開平１－９６３０７号公報Japanese Patent Application Laid-Open No. 1-96307 特開２００２-１７８２１１号公報JP 2002-178211 A ＵＳ２００８／０２４７８９９Ａ１US2008/0247899 A1 特表２００２-５０４０２７号公報JP 2002-504027 A

本発明は、工具本体の外周に一対のねじれ溝が形成されると共に、工具本体の先端部に超高圧焼結材料で構成された切れ刃を有するねじれた超高圧焼結チップが取り付けられて、一対のねじれ溝に沿って超高圧焼結材料で構成された切れ刃が設けられた回転式切削工具における前記のような問題を解決することを課題とするものである。 The present invention aims to solve the above-mentioned problems in a rotary cutting tool in which a pair of helical grooves are formed on the outer periphery of the tool body, and a twisted ultra-high pressure sintered tip having a cutting edge made of ultra-high pressure sintered material is attached to the tip of the tool body, and a cutting edge made of ultra-high pressure sintered material is provided along the pair of helical grooves.

すなわち、本発明においては、前記のような回転式切削工具において、工具本体の径が小さい場合にも、一対のねじれ溝に沿って超高圧焼結材料で構成された切れ刃を簡単に設けることができると共に、超高圧焼結材料で構成された切れ刃を工具本体の軸方向に長く設けることができ、さらにねじれ溝のねじれ角が異なる様々な回転式切削工具においても、超高圧焼結材料で構成された切れ刃を、一対のねじれ溝に沿って簡単に設けることができるようにすることを課題とするものである。 In other words, the present invention aims to make it possible to easily provide cutting edges made of ultra-high pressure sintered material along a pair of helical grooves in a rotary cutting tool such as the one described above, even when the diameter of the tool body is small, and to provide cutting edges made of ultra-high pressure sintered material long in the axial direction of the tool body, and further to make it possible to easily provide cutting edges made of ultra-high pressure sintered material along a pair of helical grooves even in various rotary cutting tools with different helical angles of the helical grooves.

本発明に係る回転式切削工具においては、前記のような課題を解決するため、工具本体の外周に一対のねじれ溝が形成されると共に、工具本体の先端部に超高圧焼結材料で構成された切れ刃を有する超高圧焼結体が取り付けられて、一対のねじれ溝に沿って超高圧焼結材料で構成された切れ刃が設けられた回転式切削工具において、工具本体の中心を通るようにして両側のねじれ溝に至る取付用ねじれ溝を設け、超高圧焼結材料で構成された切れ刃が径方向両側に設けられた超高圧焼結チップを、前記の取付用ねじれ溝内に工具本体の軸方向に複数段積層させて、超高圧焼結材料で構成された切れ刃を一対のねじれ溝に沿って設けるようにした。 In order to solve the above problems, the rotary cutting tool according to the present invention has a pair of twist grooves formed on the outer periphery of the tool body, and an ultra-high pressure sintered body having cutting edges made of ultra-high pressure sintered material is attached to the tip of the tool body, and cutting edges made of ultra-high pressure sintered material are provided along the pair of twist grooves. A twist groove for attachment is provided that passes through the center of the tool body and reaches the twist grooves on both sides, and ultra-high pressure sintered tips having cutting edges made of ultra-high pressure sintered material on both radial sides are stacked in multiple stages in the axial direction of the tool body within the twist groove for attachment, so that cutting edges made of ultra-high pressure sintered material are provided along the pair of twist grooves.

そして、このように工具本体の中心を通るようにして両側のねじれ溝に至る取付用ねじれ溝を設け、超高圧焼結材料で構成された切れ刃が径方向両側に設けられた超高圧焼結チップを、前記の取付用ねじれ溝内に工具本体の軸方向に複数段積層させて、超高圧焼結材料で構成された切れ刃を一対のねじれ溝に沿って設けるようにすると、工具本体の径が小さい場合にも、一対のねじれ溝に沿って超高圧焼結材料で構成された切れ刃を簡単に設けることができると共に、超高圧焼結チップを工具本体の軸方向に積層させる数を多くすることによって、超高圧焼結材料で構成された切れ刃を工具本体の軸方向に長く形成することができ、さらにねじれ溝のねじれ角が異なる回転式切削工具を得る場合にも、ねじれ溝に対応して取付用ねじれ溝のねじれ角を変更させて、これに対応した超高圧焼結チップを工具本体の軸方向に積層させることにより、ねじれ溝のねじれ角等が異なる各種の回転式切削工具を簡単に製造できるようになる。 In this way, by providing a mounting helical groove that passes through the center of the tool body and reaches the helical grooves on both sides, and stacking ultra-high pressure sintered chips with cutting edges made of ultra-high pressure sintered material on both radial sides in the mounting helical groove in multiple stages in the axial direction of the tool body, cutting edges made of ultra-high pressure sintered material can be provided along the pair of helical grooves, even if the diameter of the tool body is small, cutting edges made of ultra-high pressure sintered material can be easily provided along the pair of helical grooves, and by increasing the number of ultra-high pressure sintered chips stacked in the axial direction of the tool body, cutting edges made of ultra-high pressure sintered material can be formed long in the axial direction of the tool body. Furthermore, when obtaining rotary cutting tools with different helical angles of the helical grooves, it is possible to easily manufacture various rotary cutting tools with different helical angles of the helical grooves by changing the helical angle of the mounting helical groove corresponding to the helical groove and stacking the corresponding ultra-high pressure sintered chips in the axial direction of the tool body.

また、本発明の回転式切削工具においては、前記の取付用ねじれ溝内で積層させる各超高圧焼結チップの積層部分に段部を設け、積層させる超高圧焼結チップに形成された段部相互を接合させて、超高圧焼結チップを積層させることが好ましい。このようにすると、接合された各超高圧焼結チップにおける一方のねじれ溝側と他方のねじれ溝側とにおける切れ刃の接合位置が、軸方向においてずれた状態になり、回転式切削工具を回転させて切削を行う場合に、一方のねじれ溝側における切れ刃の接合部分と、他方のねじれ溝側におけるに切れ刃の接合部分との何れもが、接合された超高圧焼結チップにおける反対のねじれ溝側の切れ刃によって切削されて、切削加工面の仕上りがよくなる。 In addition, in the rotary cutting tool of the present invention, it is preferable to provide a step in the stacked portion of each ultra-high pressure sintered chip to be stacked in the mounting helical groove, and to stack the ultra-high pressure sintered chips by joining the steps formed on the stacked ultra-high pressure sintered chips to each other. In this way, the joining positions of the cutting edges on one helical groove side and the other helical groove side of each joined ultra-high pressure sintered chip are shifted in the axial direction, and when cutting is performed by rotating the rotary cutting tool, both the joining portion of the cutting edge on one helical groove side and the joining portion of the cutting edge on the other helical groove side are cut by the cutting edge on the opposite helical groove side of the joined ultra-high pressure sintered chip, resulting in a good finish on the machined surface.

また、本発明の回転式切削工具においては、前記の各超高圧焼結チップの半径方向両側の外周に切れ刃が形成された超高圧焼結チップを用い、前記の超高圧焼結チップを取付用ねじれ溝内で積層させて、一対のねじれ溝の外周に沿った切れ刃を形成したエンドミルとして使用することができる。 In addition, in the rotary cutting tool of the present invention, ultra-high pressure sintered tips having cutting edges formed on the outer periphery on both radial sides of each of the ultra-high pressure sintered tips are used, and the ultra-high pressure sintered tips are stacked within a mounting helical groove, allowing the tool to be used as an end mill with cutting edges formed along the outer periphery of a pair of helical grooves.

そして、このように各超高圧焼結チップの半径方向両側の外周に設けた切れ刃によって、一対のねじれ溝の外周に沿った切れ刃を形成したエンドミルとして使用する場合、工具本体の先端側に設けられた超高圧焼結チップの先端面に底刃を形成すると、工具本体の先端側に設けられた超高圧焼結チップの先端面に設けた底刃によって座ぐり加工等も行えるようになる。 When used as an end mill with cutting edges along the outer periphery of a pair of twisted grooves formed by cutting edges on both radial sides of each ultra-high pressure sintered tip, if a bottom cutting edge is formed on the tip surface of the ultra-high pressure sintered tip provided on the tip side of the tool body, countersinking and other processes can also be performed by the bottom cutting edge on the tip surface of the ultra-high pressure sintered tip provided on the tip side of the tool body.

また、本発明に係る回転式切削工具の製造方法においては、工具本体の外周に一対のねじれ溝が形成されると共に、超高圧焼結材料で構成された切れ刃を有するねじれた超高圧焼結チップが、工具本体の先端部に形成されたねじれ溝に沿って取り付けられた回転式切削工具の製造方法において、棒状になった工具本体の先端から軸方向に、超高圧焼結材料で構成されたねじれた超高圧焼結チップを取り付ける取付用ねじれ溝を設け、前記の取付用ねじれ溝内に、超高圧焼結材料で構成された超高圧焼結チップ片を工具本体の軸方向に複数段積層させて取り付け、その後、前記の工具本体の先端部の外周に、一対のねじれ溝を加工して、前記の超高圧焼結材料で構成された超高圧焼結チップ片によってねじれ溝のすくい面を形成すると共に、前記の各超高圧焼結チップ片の径方向両側に切れ刃を形成するようにした。 In addition, in the method of manufacturing a rotary cutting tool according to the present invention, a pair of helical grooves are formed on the outer periphery of the tool body, and a twisted ultra-high pressure sintered tip having a cutting edge made of ultra-high pressure sintered material is attached along the helical grooves formed at the tip of the tool body. In the method of manufacturing a rotary cutting tool according to the present invention, a mounting helical groove for mounting the twisted ultra-high pressure sintered tip made of ultra-high pressure sintered material is provided in the axial direction from the tip of the rod-shaped tool body, and ultra-high pressure sintered tip pieces made of ultra-high pressure sintered material are attached in the axial direction of the tool body by stacking them in multiple stages within the mounting helical groove. After that, a pair of helical grooves are machined on the outer periphery of the tip of the tool body, and the rake face of the helical groove is formed by the ultra-high pressure sintered tip pieces made of the ultra-high pressure sintered material, and cutting edges are formed on both radial sides of each ultra-high pressure sintered tip piece.

このようにして回転式切削工具を製造すると、前記のように工具本体の径が小さい場合にも、一対のねじれ溝に沿って超高圧焼結材料で構成された切れ刃を簡単に設けることができると共に、超高圧焼結材料で構成された切れ刃を工具本体の軸方向に長くすることができ、また、ねじれ溝のねじれ角が異なる各種の回転式切削工具を簡単に製造できるようになる。 By manufacturing a rotary cutting tool in this manner, even if the diameter of the tool body is small as described above, it is possible to easily provide cutting edges made of ultra-high pressure sintered material along a pair of helical grooves, and the cutting edges made of ultra-high pressure sintered material can be lengthened in the axial direction of the tool body. It is also possible to easily manufacture various rotary cutting tools with different helical angles for the helical grooves.

また、前記の回転式切削工具の製造方法において、前記の取付用ねじれ溝内に超高圧焼結チップを積層させるにあたって、積層させる各超高圧焼結チップの積層部分に段部を設け、積層させる超高圧焼結チップに形成された段部相互を接合させて、超高圧焼結チップを積層させるようにすると、前記のように接合された各超高圧焼結チップにおける一方のねじれ溝側と他方のねじれ溝側とにおける切れ刃の接合位置が、軸方向においてずれた状態になり、回転式切削工具を回転させて切削を行う場合に、一方のねじれ溝側における切れ刃の接合部分と、他方のねじれ溝側におけるに切れ刃の接合部分との何れもが、接合された超高圧焼結チップにおける反対のねじれ溝側の切れ刃によって切削されて、切削加工面の仕上りがよくなる。 In addition, in the manufacturing method of the rotary cutting tool, when stacking the ultra-high pressure sintered chips in the mounting helical groove, a step is provided in the stacked portion of each ultra-high pressure sintered chip to be stacked, and the step portions formed on the ultra-high pressure sintered chips to be stacked are joined to each other to stack the ultra-high pressure sintered chips. In this way, the joining positions of the cutting edges on one helical groove side and the other helical groove side of each joined ultra-high pressure sintered chip are shifted in the axial direction, and when the rotary cutting tool is rotated to perform cutting, both the joining portion of the cutting edge on one helical groove side and the joining portion of the cutting edge on the other helical groove side are cut by the cutting edge on the opposite helical groove side of the joined ultra-high pressure sintered chip, resulting in a good finish on the machined surface.

また、前記の回転式切削工具の製造方法において、前記の棒状になった工具本体に対して、前記の取付用ねじれ溝を放電ワイヤー加工により加工すると共に、前記の各超高圧焼結チップを放電加工により超高圧焼結基材から切り出し加工し、さらに放電加工により、工具本体の先端部に一対のねじれ溝を加工して、前記の超高圧焼結材料で構成された超高圧焼結チップによってねじれ溝のすくい面を形成すると共に、各超高圧焼結チップの径方向両側に切れ刃を形成するようにすると、ねじれ溝のねじれ角やねじれ方向等が異なる各種の回転式切削工具を簡単に製造できるようになる。 In addition, in the manufacturing method of the rotary cutting tool, the mounting twist groove is machined on the rod-shaped tool body by electric discharge wire machining, each ultra-high pressure sintered tip is cut out from the ultra-high pressure sintered base material by electric discharge machining, and a pair of twist grooves is machined on the tip of the tool body by electric discharge machining, the rake face of the twist groove is formed by the ultra-high pressure sintered tip made of the ultra-high pressure sintered material, and cutting edges are formed on both radial sides of each ultra-high pressure sintered tip, making it easy to manufacture various rotary cutting tools with different twist angles and twist directions of the twist groove.

また、前記の回転式切削工具の製造方法において、前記の工具本体の先端部の外周に、一対のねじれ溝を加工して、前記の超高圧焼結材料で構成された超高圧焼結チップによってねじれ溝のすくい面を形成すると共に、前記の各超高圧焼結チップの径方向両側の外周に切れ刃を設けて、一対のねじれ溝の外周に沿った切れ刃を形成することにより、この回転式切削工具をエンドミルとして使用することができ、さらに工具本体の先端側に設けられた超高圧焼結チップの先端面に底刃を形成すると、超高圧焼結チップの先端面に設けた底刃によって座ぐり加工等も行えるようになる。 In addition, in the manufacturing method of the rotary cutting tool, a pair of twisted grooves is machined on the outer periphery of the tip of the tool body, and the cutting surface of the twisted groove is formed by the ultra-high pressure sintered tip made of the ultra-high pressure sintered material. At the same time, cutting edges are provided on the outer periphery on both radial sides of each ultra-high pressure sintered tip to form cutting edges along the outer periphery of the pair of twisted grooves, so that the rotary cutting tool can be used as an end mill. Furthermore, if a bottom blade is formed on the tip surface of the ultra-high pressure sintered tip provided on the tip side of the tool body, countersinking and other processes can also be performed by the bottom blade provided on the tip surface of the ultra-high pressure sintered tip.

本発明における回転式切削工具及び回転式切削工具の製造方法においては、前記のように工具本体の中心を通るようにして両側のねじれ溝に至る取付用ねじれ溝を設け、超高圧焼結材料で構成された切れ刃が径方向両側に設けられた超高圧焼結チップを、前記の取付用ねじれ溝内に工具本体の軸方向に複数段積層させて、超高圧焼結材料で構成された切れ刃を一対のねじれ溝に沿って設けるようにしたため、工具本体の径が小さい場合にも、一対のねじれ溝に沿って超高圧焼結材料で構成された切れ刃を簡単に設けることができると共に、超高圧焼結チップを工具本体の軸方向に積層させる数を多くすることによって、超高圧焼結材料で構成された切れ刃を工具本体の軸方向に長く形成することができ、さらにねじれ溝のねじれ角等が異なる回転式切削工具を得る場合にも、ねじれ溝に対応して取付用ねじれ溝のねじれ角を変更させて、これに対応した超高圧焼結チップを工具本体の軸方向に積層させることにより、ねじれ溝のねじれ角等が異なる各種の回転式切削工具を簡単に製造できるようになる。 In the rotary cutting tool and the manufacturing method of the rotary cutting tool of the present invention, as described above, a mounting helical groove is provided that passes through the center of the tool body and reaches the helical grooves on both sides, and ultra-high pressure sintered chips with cutting edges made of ultra-high pressure sintered material on both radial sides are stacked in multiple stages in the axial direction of the tool body within the mounting helical groove, so that the cutting edges made of ultra-high pressure sintered material are provided along the pair of helical grooves. Therefore, even if the diameter of the tool body is small, cutting edges made of ultra-high pressure sintered material can be easily provided along the pair of helical grooves, and by increasing the number of ultra-high pressure sintered chips stacked in the axial direction of the tool body, the cutting edges made of ultra-high pressure sintered material can be formed long in the axial direction of the tool body. Furthermore, even when obtaining rotary cutting tools with different helical angles, etc. of the helical grooves, the helical angle of the mounting helical grooves can be changed to correspond to the helical grooves, and the corresponding ultra-high pressure sintered chips can be stacked in the axial direction of the tool body, making it easy to manufacture various rotary cutting tools with different helical angles of the helical grooves.

本発明の実施形態に係る回転式切削工具において、工具本体における取付用ねじれ溝から各超高圧焼結チップを取り出した状態を示した分解斜視図である。FIG. 2 is an exploded perspective view showing a rotary cutting tool according to an embodiment of the present invention with each ultra-high pressure sintered tip removed from a mounting helical groove in a tool body. 同実施形態に係る回転式切削工具において、取付用ねじれ溝から各超高圧焼結チップを取り出した工具本体の先端側の概略正面図である。13 is a schematic front view of the tip side of the tool body with each ultra-high pressure sintered tip removed from the mounting spiral groove in the rotary cutting tool according to the embodiment. FIG. 同実施形態に係る回転式切削工具において、取付用ねじれ溝から取り外した各超高圧焼結チップを、工具本体の先端側から後方側に向けて積層させるようにして接合させた状態を示した概略斜視図である。This is a schematic oblique view showing the state in which each ultra-high pressure sintered tip removed from the mounting spiral groove is joined by stacking from the tip side to the rear side of the tool body in the rotary cutting tool of the same embodiment. 同実施形態に係る回転式切削工具において、取付用ねじれ溝から取り外した各超高圧焼結チップを、工具本体の先端側から後方側に向けて積層させるようにして接合させた状態を示した概略側面図である。This is a schematic side view showing the state in which each ultra-high pressure sintered tip removed from the mounting spiral groove is joined by stacking from the tip side to the rear side of the tool body in the rotary cutting tool of the same embodiment. 同実施形態に係る回転式切削工具において、各超高圧焼結チップを工具本体の取付用ねじれ溝内に工具本体の先端側から後方側に向けて積層させて取り付けた状態を示した概略斜視図である。FIG. 11 is a schematic oblique view showing the state in which each ultra-high pressure sintered tip is stacked and attached from the tip side to the rear side of the tool body in the mounting spiral groove of the tool body in the rotary cutting tool according to the same embodiment. 本発明の実施形態に係る回転式切削工具の製造方法において、棒状になった工具本体の先端から軸方向に、超高圧焼結材料で構成されたねじれた超高圧焼結チップを取り付ける取付用ねじれ溝を設けた状態を示した概略斜視図である。FIG. 11 is a schematic perspective view showing a state in which a twisted mounting groove for mounting a twisted ultra-high pressure sintered tip made of ultra-high pressure sintered material is provided in the axial direction from the tip of a rod-shaped tool body in a manufacturing method for a rotary cutting tool according to an embodiment of the present invention. 本発明の実施形態に係る回転式切削工具の製造方法において、各超高圧焼結チップを製造するのに使用する基板の上に超高圧焼結基材を設けたものを示した概略側面図である。1 is a schematic side view showing a method for manufacturing a rotary cutting tool according to an embodiment of the present invention, in which an ultra-high pressure sintered base material is provided on a substrate used to manufacture each ultra-high pressure sintered tip. FIG. 同実施形態に係る回転式切削工具の製造方法において、棒状になった工具本体に設けた取付用ねじれ溝内に取り付ける用いる各超高圧焼結チップの状態を示した概略斜視図である。FIG. 11 is a schematic perspective view showing the state of each ultra-high pressure sintered tip to be attached to a rod-shaped tool body in a spiral attachment groove in the manufacturing method for the rotary cutting tool according to the embodiment. 同実施形態に係る回転式切削工具の製造方法において、棒状になった工具本体に設けた取付用ねじれ溝内に各超高圧焼結チップを取り付ける前に、各超高圧焼結チップを工具本体の先端側から後方側に向けて積層させるようにして接合させた状態を示した概略斜視図である。FIG. 11 is a schematic oblique view showing a state in which each ultra-high pressure sintered tip is joined by stacking it from the tip side to the rear side of the tool body before attaching it to a spiral mounting groove provided in a rod-shaped tool body in a manufacturing method of a rotary cutting tool according to the same embodiment. 同実施形態に係る回転式切削工具の製造方法において、棒状になった工具本体に設けた取付用ねじれ溝内に、各超高圧焼結チップを工具本体の先端側から後方側に向けて積層させて取り付けた状態を示した概略斜視図である。FIG. 11 is a schematic perspective view showing a state in which each ultra-high pressure sintered tip is stacked from the tip side to the rear side of the tool body and attached within a spiral attachment groove provided in the rod-shaped tool body in the manufacturing method of the rotary cutting tool according to the same embodiment.

以下、本発明の一実施形態における回転式切削工具及び回転式切削工具の製造方法を添付図面に基づいて具体的に説明する。なお、本発明における回転式切削工具及び回転式切削工具の製造方法は、下記の実施形態に示したものに限定されず、その要旨を変更しない範囲において適宜変更して実施できるものである。 The rotary cutting tool and the method for manufacturing the rotary cutting tool according to one embodiment of the present invention will be specifically described below with reference to the attached drawings. Note that the rotary cutting tool and the method for manufacturing the rotary cutting tool according to the present invention are not limited to the embodiment shown below, and can be modified as appropriate without departing from the gist of the present invention.

この実施形態においては、回転式切削工具がエンドミルである場合について説明する。 In this embodiment, the rotary cutting tool is an end mill.

この実施形態における回転式切削工具Ｘにおいては、外周に一対のねじれ溝１１が形成された超硬合金で構成された工具本体１０の先端部に、ダイヤモンドや立方晶窒化硼素等の超高圧焼結材料で構成された切れ刃２１を有する超高圧焼結体２０を取り付けて、一対のねじれ溝１１に沿って超高圧焼結材料で構成された切れ刃２１を設けるようにしている。 In this embodiment, the rotary cutting tool X has a tool body 10 made of cemented carbide with a pair of helical grooves 11 formed on its outer periphery, and an ultra-high pressure sintered body 20 having a cutting edge 21 made of an ultra-high pressure sintered material such as diamond or cubic boron nitride is attached to the tip of the tool body 10, so that the cutting edge 21 made of the ultra-high pressure sintered material is provided along the pair of helical grooves 11.

ここで、この実施形態における回転式切削工具Ｘにおいては、図１，図２等に示すように、工具本体１０の軸心Ｏを通るようにして両側のねじれ溝１１に至る取付用ねじれ溝１２を設けるようにしている。 In this embodiment, the rotary cutting tool X has a mounting helical groove 12 that passes through the axis O of the tool body 10 and reaches the helical grooves 11 on both sides, as shown in Figures 1 and 2.

また、この実施形態においては、前記の超高圧焼結体２０として、図１に示すように、ダイヤモンドや立方晶窒化硼素等の超高圧焼結材料で構成された切れ刃２１が径方向両側の外周に設けられた４種類の超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄを、前記の取付用ねじれ溝１２における工具本体１０の軸方向の位置に対応するようにして形成すると共に、工具本体１０の先端側における超高圧焼結チップ２０Ａの両側の先端面に、それぞれ底刃２２を形成するようにしている。 In this embodiment, as shown in FIG. 1, the ultra-high pressure sintered body 20 is formed as four types of ultra-high pressure sintered tips 20A, 20B, 20C, and 20D, each of which has a cutting edge 21 made of ultra-high pressure sintered material such as diamond or cubic boron nitride on the outer periphery on both radial sides, so as to correspond to the axial position of the tool body 10 in the mounting helical groove 12, and a bottom cutting edge 22 is formed on each of the tip surfaces on both sides of the ultra-high pressure sintered tip 20A at the tip side of the tool body 10.

そして、この実施形態における回転式切削工具Ｘにおいては、前記の各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄを、図３及び図４に示すように、工具本体１０の先端側から後方側に向けて積層させるようにして接合させ、各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄを、図５に示すように、前記の取付用ねじれ溝１２内に順々に嵌め込んで、ろう付け等によって工具本体１０に取り付けるようにしている。 In the rotary cutting tool X in this embodiment, the ultra-high pressure sintered tips 20A, 20B, 20C, and 20D are joined by stacking them from the tip side to the rear side of the tool body 10 as shown in Figures 3 and 4, and the ultra-high pressure sintered tips 20A, 20B, 20C, and 20D are fitted in order into the mounting helical groove 12 as shown in Figure 5, and attached to the tool body 10 by brazing or the like.

このように、各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄを、工具本体１０の先端側から後方側に向けて積層させて接合させ、前記の取付用ねじれ溝１２内に順々に嵌め込んで、ろう付け等によって工具本体１０に取り付けるようにすると、工具本体１０の径が小さい場合にも、各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄにより、一対のねじれ溝１１に沿って超高圧焼結材料で構成された切れ刃２１を簡単に設けることができると共に、各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄにおける超高圧焼結材料で構成された切れ刃２１が接合されて、超高圧焼結材料で構成された切れ刃２１を一対のねじれ溝１１に沿って工具本体１０の軸方向に長く設けることができるようになる。 In this way, the ultra-high pressure sintered tips 20A, 20B, 20C, and 20D are stacked and joined from the tip side to the rear side of the tool body 10, fitted one by one into the above-mentioned mounting twist groove 12, and attached to the tool body 10 by brazing or the like. Even if the diameter of the tool body 10 is small, the ultra-high pressure sintered tips 20A, 20B, 20C, and 20D can easily provide cutting edges 21 made of ultra-high pressure sintered material along a pair of twist grooves 11. Furthermore, the cutting edges 21 made of ultra-high pressure sintered material in the ultra-high pressure sintered tips 20A, 20B, 20C, and 20D are joined, so that the cutting edges 21 made of ultra-high pressure sintered material can be provided long in the axial direction of the tool body 10 along a pair of twist grooves 11.

また、この実施形態においては、前記の超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄを積層させるようにして接合させるにあたり、図１、図３及び図４に示すように、積層させる各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄの積層部分に段部２３を設け、積層させる超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄに形成された段部２３相互を接合させて、超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄを積層させるようにしている。 In addition, in this embodiment, when the ultra-high pressure sintered chips 20A, 20B, 20C, and 20D are joined by stacking them, as shown in Figures 1, 3, and 4, a step portion 23 is provided in the stacked portion of each of the ultra-high pressure sintered chips 20A, 20B, 20C, and 20D to be stacked, and the step portions 23 formed on the ultra-high pressure sintered chips 20A, 20B, 20C, and 20D to be stacked are joined to each other to stack the ultra-high pressure sintered chips 20A, 20B, 20C, and 20D.

このように、積層させる超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄに形成された段部２３相互を接合させて、超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄを積層させると、図４に示すように、接合された各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄにおける一方のねじれ溝側と他方のねじれ溝側とにおける切れ刃２１の接合位置が、軸方向にずれた状態になり、この回転式切削工具Ｘを回転させて切削を行う場合に、一方のねじれ溝側における切れ刃２１の接合部分と、他方のねじれ溝側におけるに切れ刃２１の接合部分との何れもが、接合された超高圧焼結チップにおける反対のねじれ溝側の切れ刃２１によって切削されて、切削加工面の仕上りがよくなる。 In this way, when the step portions 23 formed on the stacked ultra-high pressure sintered chips 20A, 20B, 20C, 20D are joined together and the ultra-high pressure sintered chips 20A, 20B, 20C, 20D are stacked, as shown in FIG. 4, the joining positions of the cutting edges 21 on one twist groove side and the other twist groove side of each joined ultra-high pressure sintered chip 20A, 20B, 20C, 20D are shifted in the axial direction. When cutting is performed by rotating this rotary cutting tool X, both the joining portion of the cutting edge 21 on one twist groove side and the joining portion of the cutting edge 21 on the other twist groove side are cut by the cutting edge 21 on the opposite twist groove side of the joined ultra-high pressure sintered chips, resulting in a good finish on the machined surface.

次に、前記の実施形態における回転式切削工具Ｘを製造する実施形態について説明する。 Next, an embodiment for manufacturing the rotary cutting tool X in the above embodiment will be described.

この実施形態においては、前記の回転式切削工具Ｘを製造するにあたり、図６に示すように、超硬合金で構成された棒状になった工具本体１１０の先端から軸方向にねじれた取付用ねじれ溝１１２を、放電ワイヤー加工により加工するようにしている。 In this embodiment, when manufacturing the rotary cutting tool X, as shown in FIG. 6, a mounting helical groove 112 that is twisted in the axial direction from the tip of a rod-shaped tool body 110 made of cemented carbide is machined by electric discharge wire machining.

また、この実施形態においては、各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを得るにあたり、図７に示すような基板Ｐの上に超高圧焼結基材Ｙされたものを用い、この超高圧焼結基材Ｙから放電加工により、図８に示すように、前記の工具本体１１０における取付用ねじれ溝１１２に沿うようにして、ねじれた各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを切り出し加工するようにしている。 In addition, in this embodiment, to obtain each of the ultra-high pressure sintered chips 120A, 120B, 120C, and 120D, an ultra-high pressure sintered base material Y is placed on a substrate P as shown in FIG. 7, and each of the twisted ultra-high pressure sintered chips 120A, 120B, 120C, and 120D is cut out from this ultra-high pressure sintered base material Y by electric discharge machining so as to follow the mounting helical groove 112 in the tool body 110 as shown in FIG. 8.

そして、この実施形態においては、図９に示すように、前記の各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを、工具本体１１０の先端側から後方側に向けて積層させるようにして接合させ、図１０に示すように、各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを前記の工具本体１１０における取付用ねじれ溝１１２内に順々に嵌め込んで、各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを、ろう付け等によって工具本体１１０に取り付けるようにしている。 In this embodiment, as shown in FIG. 9, the ultra-high pressure sintered tips 120A, 120B, 120C, and 120D are joined by stacking them from the tip side to the rear side of the tool body 110, and as shown in FIG. 10, the ultra-high pressure sintered tips 120A, 120B, 120C, and 120D are fitted in order into the mounting helical grooves 112 in the tool body 110, and the ultra-high pressure sintered tips 120A, 120B, 120C, and 120D are attached to the tool body 110 by brazing or the like.

ここで、この実施形態において、前記の各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを積層させるようにして接合させるにあたっては、図８及び図９に示すように、積層させる各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄの積層部分に段部１２３を設け、積層させる超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄに形成された段部１２３相互を接合させて、各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを積層させるようにしている。 In this embodiment, when the ultra-high pressure sintered chips 120A, 120B, 120C, and 120D are joined together by stacking them, as shown in Figures 8 and 9, steps 123 are provided in the stacked portions of the ultra-high pressure sintered chips 120A, 120B, 120C, and 120D, and the steps 123 formed on the ultra-high pressure sintered chips 120A, 120B, 120C, and 120D are joined together to stack the ultra-high pressure sintered chips 120A, 120B, 120C, and 120D.

そして、前記のようにして工具本体１１０における取付用ねじれ溝１１２内に、４種類の超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄをろう付け等によって工具本体１１０に取り付けた後は、前記の工具本体１１０と各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄに対して放電ワイヤー加工を行い、前記の図５に示すように、工具本体１０の先端部に一対のねじれ溝１１を形成して、各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄがねじれ溝１１のすくい面になるようにすると共に、各超高圧焼結チップ２０Ａ，２０Ｂ，２０Ｃ，２０Ｄの径方向両側の外周に切れ刃２１を形成し、さらに工具本体１０の先端側における超高圧焼結チップ２０Ａの両側の先端面にそれぞれ底刃２２を形成するようにしている。 Then, after the four types of ultra-high pressure sintered tips 120A, 120B, 120C, and 120D are attached to the tool body 110 by brazing or the like in the mounting helical groove 112 in the tool body 110 as described above, the tool body 110 and each ultra-high pressure sintered tip 120A, 120B, 120C, and 120D are subjected to discharge wire machining, and as shown in FIG. 5, a pair of helical grooves 11 are formed at the tip of the tool body 10, so that each ultra-high pressure sintered tip 20A, 20B, 20C, and 20D becomes the rake face of the helical groove 11, and cutting edges 21 are formed on the outer periphery on both radial sides of each ultra-high pressure sintered tip 20A, 20B, 20C, and 20D, and further bottom edges 22 are formed on the tip faces on both sides of the ultra-high pressure sintered tip 20A at the tip side of the tool body 10.

このようにして回転式切削工具Ｘを製造するようにした場合、放電ワイヤー加工により、工具本体１１０に設ける取付用ねじれ溝１１２のねじれ角やねじれ方向を自由に変更することができると共に、この取付用ねじれ溝１１２のねじれ角やねじれ方向に対応させて、適切なねじれ状態になって各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄを放電加工により簡単に切り出し加工することができ、このような工具本体１１０と各超高圧焼結チップ１２０Ａ，１２０Ｂ，１２０Ｃ，１２０Ｄとを用いることにより、一対のねじれ溝１１のねじれ角やねじれ方向が異なる各種の回転式切削工具Ｘを簡単に製造できるようになる。 When the rotary cutting tool X is manufactured in this manner, the twist angle and twist direction of the mounting helical groove 112 provided in the tool body 110 can be freely changed by discharge wire machining, and the ultra-high pressure sintered tips 120A, 120B, 120C, and 120D can be easily cut out by discharge machining in an appropriate twist state corresponding to the twist angle and twist direction of the mounting helical groove 112. By using such a tool body 110 and each ultra-high pressure sintered tip 120A, 120B, 120C, and 120D, it is possible to easily manufacture various rotary cutting tools X with different twist angles and twist directions of the pair of helical grooves 11.

なお、前記の実施形態においては、回転式切削工具Ｘがエンドミルである場合について説明したが、本発明の回転式切削工具Ｘは、エンドミルに限定されるものではない。 In the above embodiment, the rotary cutting tool X is an end mill, but the rotary cutting tool X of the present invention is not limited to an end mill.

例えば、図示していないが、前記の特許文献３に示されるように、工具本体の先端部の径方向に設けられた取付部内に嵌め込むようにして先端切れ刃を有する超高圧焼結チップを取り付けるようにしたドリルにおいても、工具本体の中心を通るようにして両側のねじれ溝に至る取付用ねじれ溝を設け、超高圧焼結材料で構成された切れ刃が径方向両側に設けられた超高圧焼結チップを、前記の取付用ねじれ溝内に工具本体の軸方向に複数段積層させて、超高圧焼結材料で構成された切れ刃を一対のねじれ溝に沿って設けるようにすることができる。 For example, although not shown, as shown in the above-mentioned Patent Document 3, even in a drill in which an ultra-high pressure sintered tip having a tip cutting edge is attached by fitting it into an attachment portion provided radially at the tip of the tool body, a mounting twist groove is provided that passes through the center of the tool body and reaches the twist grooves on both sides, and ultra-high pressure sintered tips having cutting edges made of ultra-high pressure sintered material provided on both radial sides are stacked in multiple stages in the mounting twist groove in the axial direction of the tool body, so that the cutting edges made of ultra-high pressure sintered material are provided along the pair of twist grooves.

１０：工具本体
１１：ねじれ溝
１２：取付用ねじれ溝
２０：超高圧焼結体
２０Ａ：超高圧焼結チップ
２０Ｂ：超高圧焼結チップ
２０Ｃ：超高圧焼結チップ
２０Ｄ：超高圧焼結チップ
２１：切れ刃
２２：底刃
２３：段部
１１０：工具本体
１１２：取付溝
１２０Ａ：超高圧焼結チップ
１２０Ｂ：超高圧焼結チップ
１２０Ｃ：超高圧焼結チップ
１２０Ｄ：超高圧焼結チップ
１２３：段部
Ｏ：軸心
Ｐ：基板
Ｘ：回転式切削工具
Ｙ：超高圧焼結基材 10: Tool body 11: Twist groove 12: Mounting twist groove 20: Ultra-high pressure sintered body 20A: Ultra-high pressure sintered tip 20B: Ultra-high pressure sintered tip 20C: Ultra-high pressure sintered tip 20D: Ultra-high pressure sintered tip 21: Cutting edge 22: Bottom edge 23: Step 110: Tool body 112: Mounting groove 120A: Ultra-high pressure sintered tip 120B: Ultra-high pressure sintered tip 120C: Ultra-high pressure sintered tip 120D: Ultra-high pressure sintered tip 123: Step O: Shaft center P: Substrate X: Rotary cutting tool Y: Ultra-high pressure sintered base material

Claims

A rotary cutting tool in which a pair of twist grooves are formed on the outer periphery of the tool body, an ultra-high pressure sintered body having cutting edges made of ultra-high pressure sintered material is attached to the tip of the tool body, and cutting edges made of ultra-high pressure sintered material are provided along the pair of twist grooves, a twist groove for attachment is provided that passes through the center of the tool body and reaches the twist grooves on both sides, and ultra-high pressure sintered tips having cutting edges made of ultra-high pressure sintered material on both radial sides are stacked in multiple stages in the axial direction of the tool body within the twist groove for attachment, and cutting edges made of ultra-high pressure sintered material are provided along the pair of twist grooves.

The rotary cutting tool according to claim 1, characterized in that a step is provided in the stacked portion of each ultra-high pressure sintered chip to be stacked in the mounting helical groove, and the steps formed on the ultra-high pressure sintered chips to be stacked are joined to each other, thereby stacking the ultra-high pressure sintered chips.

The rotary cutting tool according to claim 1 or 2 is characterized in that it is an end mill using ultra-high pressure sintered tips with cutting edges formed on the outer circumference on both radial sides of each ultra-high pressure sintered tip, and stacking the ultra-high pressure sintered tips in a mounting helical groove to form cutting edges along the outer circumference of a pair of helical grooves.

The rotary cutting tool according to claim 3, characterized in that a bottom cutting edge is formed on the tip surface of the ultra-high pressure sintered tip provided on the tip side of the tool body.

A method for manufacturing a rotary cutting tool in which a pair of twisted grooves are formed on the outer periphery of the tool body, and a twisted ultra-high pressure sintered tip having a cutting edge made of ultra-high pressure sintered material is attached along the twisted grooves formed at the tip of the tool body, a twisted groove for attaching the twisted ultra-high pressure sintered tip made of ultra-high pressure sintered material is provided in the axial direction from the tip of the rod-shaped tool body, and ultra-high pressure sintered tip pieces made of ultra-high pressure sintered material are attached in the axial direction of the tool body by stacking them in multiple stages within the twisted groove for attachment, and then a pair of twisted grooves are machined on the outer periphery of the tip of the tool body to form a rake face of the twisted groove with the ultra-high pressure sintered tip pieces made of ultra-high pressure sintered material, and cutting edges are formed on both radial sides of each ultra-high pressure sintered tip piece.

The method for manufacturing a rotary cutting tool according to claim 5, characterized in that when stacking ultra-high pressure sintered chips in the axial direction of the tool body within the mounting helical groove, a step is provided in the stacked portion of each ultra-high pressure sintered chip to be stacked, and the steps formed on the ultra-high pressure sintered chips to be stacked are joined to each other to stack the ultra-high pressure sintered chips.

A method for manufacturing a rotary cutting tool according to claim 5 or 6, characterized in that the mounting helical groove is machined on the rod-shaped tool body by electric discharge wire machining, each of the ultra-high pressure sintered tip pieces is cut out from the ultra-high pressure sintered base material by electric discharge machining, and a pair of helical grooves is machined on the tip of the tool body by electric discharge machining, forming a rake face of the helical groove with the ultra-high pressure sintered tip piece made of the ultra-high pressure sintered material, and forming cutting edges on both radial sides of each ultra-high pressure sintered tip piece.

The method for manufacturing a rotary cutting tool according to claim 5 or 6, characterized in that a pair of helical grooves are machined on the outer periphery of the tip of the tool body, the rake faces of the helical grooves are formed by the ultra-high pressure sintered tip pieces made of the ultra-high pressure sintered material, and cutting edges are provided on the outer periphery on both radial sides of each ultra-high pressure sintered tip piece to form cutting edges along the outer periphery of the pair of helical grooves.