WO2003066261A1 - Rotary tool and its cutting part - Google Patents

Abstract

A rotary tool T comprising a rotator (10) having a surface opposite to a plane being machined, and a plurality of cutting parts (20) arranged on the opposite surface, and ensuring a good work for removing a coating by preventing seizure while avoiding undue biting of a tip. The cutting part (20) is composed of a grindstone (22) produced by bonding abrasive grains by a metallic binder at the inner part in the direction of turning radius of the tip, and of a sintered body (24) harder than the grindstone (22) at the outer part in the direction of turning radius thereof. The rotary tool (T) comprises tips (22a) each composed of a grindstone produced by bonding abrasive grains by a metallic binder, and tips (24a) each composed of a sintered body harder than the grindstone, wherein the cutting parts (20) are arranged such that the tips (24a) are located on the outside of the tips (22a) in the direction of turning radius of the rotator.

Description

 Description Rotary tools and their blades

 TECHNICAL FIELD The present invention relates to a rotary tool for constructing a surface of a wall or floor in a building, a ship, a bridge, or the like to remove paint, an adhesive, and the like attached to the surface, and a blade portion thereof. Background art

 2. Description of the Related Art Conventionally, as a tool for processing a floor surface or a wall surface of various structures, a rotary grinding tool in which a plurality of grindstones are arranged on an outer peripheral portion of a cup-shaped rotating body is known. For example, a large amount of diamond abrasive particles sintered in a metal binder is used for each of the grinding wheels constituting the grinding tool. Each of the grinding wheels is rotated while rotating the entire grinding tool including the grinding wheel at a high speed. By contacting the construction surface, the construction surface can be ground.

However, when the grinding tool is used to remove old paint films (especially rubber-based elastic paints and adhesives) adhered to, for example, floors and walls, etc. during repair work on concrete structures, etc. The coating film or the like is thermally fused by the frictional heat between the coating film or the like and each of the above-mentioned grindstones to cause seizure. In addition, there is a disadvantage that the wear speed of the grindstone is relatively high and it is difficult to obtain a long life of the cutting edge. Therefore, Japanese Patent Laid-Open Publication No. It discloses that a plurality of sintered diamond cutting tools are arranged at equal intervals in the circumferential direction on the obtained cutting tool mounting surface. According to this tool, while the rotating body is attached to the drive shaft of the electric motor and is rotated at a high speed, each of the cutting tools is pressed against the work surface, thereby achieving this application. The surface can be smoothly removed without seizure.

 However, the tool disclosed in this publication has a problem in that the cutting edge made of a diamond sintered body has a very high sharpness, and the cutting edge is too deeply cut into a construction surface. Such excessive biting of the cutting edge may cause cutting marks to be left on the base of the construction surface, or may cause an unnecessary load on the cutting edge to induce breakage, etc., which may shorten the life of the cutting edge. .

 Accordingly, an object of the present invention is to prevent seizure while avoiding excessive biting of the cutting edge, and to enable good removal processing. Disclosure of the invention

 In order to solve the above problems, the present invention employs the following configuration.

 That is, the present invention provides a rotary tool provided with a rotating body having a facing surface facing a construction surface, provided on the facing surface, and the rotating body is driven to rotate about an axis perpendicular to the facing surface. The surface of the construction surface is wiped off when pressed against the construction surface while being pressed.The blade part of the rotary tool having a cutting edge, and the inner part in the rotating radial direction of the cutting edge combines abrasive grains with a metal binder. The cutting edge is formed of a sintered body that is harder than the grinding stone. According to this blade portion, the outer portion in the rotational radius direction of the blade edge, that is, the portion having a high rotational circumferential speed and a large amount of cutting work, is formed of a sharply-cut hard sintered body. The surface part of the construction surface can be removed at a high speed and shallowly by the part, and seizure can be prevented. The portion with a small amount is composed of a relatively low-sharpness grindstone (a grindstone in which abrasive grains are bonded with a metal binder) having a lower hardness than that of the sintered body. You.

Further, as described above, the outer portion in the rotation radial direction having a large amount of cutting work at the cutting edge is hardened. By using the above-mentioned grindstone, the wear rate of the cutting edge can be made uniform over the radial direction of rotation by forming the inner portion in the direction of rotation radius having a relatively small cutting work amount from the sintered body. Thus, unlike the case where the entire cutting edge is made of the same material, the outer portion in the rotating radial direction of the cutting edge is worn ahead of the inner portion in the rotating radial direction, so-called settling can be prevented. Therefore, the life of the cutting edge can be maintained long.

 Furthermore, it is possible to supplementarily process a portion that cannot be completely removed by the cutting edge made of the hard sintered body by the cutting edge made of the grindstone. When a scratch is generated on the machined surface by the removal processing by the cutting edge, the scratch can be reduced or eliminated by the cutting edge made of the grinding stone. As the hard sintered body, for example, a cemented carbide, ceramic, cermet, etc. may be used, but a polycrystalline diamond sintered body (PCD) and a polycrystalline cubic boron nitride sintered body (PCBN) are particularly preferable ( Claim 2). By using a particularly hard sintered body, seizure can be more reliably prevented, and a longer tool life can be enjoyed.

 Further, as the abrasive grains bonded by the metal binder, diamond abrasive grains and CBN abrasive grains are suitable.

 Japanese Utility Model No. 3-7470 microfilm discloses a katsuyu bit in which metal-bonded diamond wheels and cemented carbide are alternately arranged for cutting reinforced concrete. However, since the cutter bit has a configuration in which the grindstone and the cemented carbide are arranged side by side in the circumferential direction (not in the radial direction), seizure is prevented while preventing excessive biting of the cutting edge as in the present invention. The effect of doing this cannot be obtained.

In the present invention, not only the inner part in the rotational radius direction of the cutting edge, but also the entire cutting part including the part, except for the cutting edge part formed of the sintered body, is a grindstone in which abrasive grains are combined with a metal binder. More preferably, it is composed of (Claim 3). According to this configuration, the above-described effects can be obtained while simplifying the structure of the entire blade portion.

 In the present invention, the ratio of the length of the cutting edge portion (rotating radially outer portion) composed of the hard sintered body to the length of the other portion (rotating radial direction inner portion) is determined by the material and rotational speed of each portion. In general, in order to prevent both seizure and excessive cutting, the length of the cutting edge composed of the sintered body should be 1% to 67% of the total cutting edge length. It is better to set it in the range of% (Claim 4).

 Further, the present invention provides a rotating body having an opposing surface facing the construction surface, and a plurality of blade portions provided side by side on the opposing surface and having a cutting edge for removing a surface portion of the construction surface in a rotational circumferential direction. A rotary tool that removes a surface portion of the construction surface by pressing each of the blades against the construction surface while rotating the rotating body about an axis orthogonal to the facing surface. A grindstone in which abrasive grains are combined with a metal binder is provided on the facing surface; and the cutting edge of the blade portion includes a cutting edge made of a sintered body harder than the grinding stone, and Is provided at a position outside the grinding wheel in the rotational radius direction of the rotating body (claim 5).

According to this rotary tool, the cutting edge composed of a sharply-cut hard sintered body removes the surface portion of the construction surface at a high speed and shallowly, thereby preventing burn-in, while being positioned radially inward of the cutting edge. In addition, the presence of a grindstone having a lower hardness than that of the sintered body and a relatively low sharpness prevents the entire cutting edge from being too deeply bitten. Further, the removal processing by the cutting edge made of the hard sintered body is assisted by the grindstone, and when the processing surface is scratched by the removal processing by the cutting edge made of the hard sintered body, It is also possible to reduce or eliminate the scratches by the grindstone. As a specific form of the rotary tool, as a blade of the blade portion, a blade configured by the grindstone, and a harder than the grindstone A cutting edge made of a sintered body, and The blades may be arranged such that the cutting edge made of the sintered body is positioned outside the cutting edge made of the whetstone in the radial direction of rotation of the rotating body. ), The grindstone has a shape that is continuous in the circumferential direction of rotation of the rotating body, and has a cutting edge made of the sintered body at a position outside the rotating body in the rotating radial direction of the rotating body. A blade portion may be provided (Claim 7).

 Further, the present invention provides a rotating body having an opposing surface facing the construction surface, and a plurality of blade portions provided side by side on the opposing surface and having a cutting edge for removing a surface portion of the construction surface in a rotational circumferential direction. A rotary tool that contacts the surface portion of the construction surface by pressing each of the blades against the construction surface while the rotating body is rotationally driven around an axis perpendicular to the facing surface. At least a part of the blade portion is configured by the blade portion according to any one of claims 1 to 4 (claim 8).

 According to this rotary tool, the cutting edge made of a sharply-cut hard sintered body removes the surface portion of the construction surface at a high speed and shallowly to prevent seizure, but has a lower hardness than the sintered body. The presence of the cutting edge composed of a relatively dull grindstone prevents the entire cutting edge from penetrating too deeply. Further, the removal processing by the cutting edge made of the hard sintered body is assisted by the cutting edge made of the grinding stone, and the scratch generated by the removal processing by the cutting edge made of the hard sintered body is removed by the grinding stone. It can also be reduced or eliminated by the configured cutting edge.

 In the rotary tool according to claim 8, not all the blades need necessarily be constituted by the blades according to any one of claims 1 to 4, but all the blades need to be If the blades according to any one of claims 1 to 4 are arranged at equal intervals in the circumferential direction (claim 9), the cutting ability is made uniform in the circumferential direction. As a result, smoother removal processing can be realized.

Further, at least a first blade portion having a blade edge made of the sintered body, and a second blade portion having a blade edge made of the whetstone, the blade edge of the second blade portion is the The second blade portion may be arranged so as to be located radially inward of the rotary body in the rotation radial direction with respect to the blade edge formed of the sintered body in the first blade portion. 0), it is possible to enjoy the effect of preventing image sticking and suppressing excessive biting. BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a perspective view of a rotary tool according to a first embodiment of the present invention as viewed from a bottom surface side.

 FIG. 2 is a perspective view of the rotary tool as viewed from above.

 FIG. 3 is a side view of the rotary tool.

 FIG. 4 is a perspective view showing an example of a driving machine to which the rotary tool is mounted.

 FIG. 5 is a perspective view of the rotary tool according to the embodiment of the present invention, which is viewed from the bottom side, and which is configured for painting a floor.

 FIG. 6 is a perspective view of the rotary tool according to the second embodiment of the present invention as viewed from the bottom side.

 FIG. 7 is a bottom view of the rotary tool of FIG.

 FIG. 8 is a perspective view of a rotary tool according to a third embodiment of the present invention as viewed from a bottom surface side.

 FIG. 9 is a bottom view of the rotary tool of FIG.

 FIG. 10 is a bottom view of the rotary tool according to the fourth embodiment of the present invention.

 FIG. 11 (a) is a bottom view of a rotary tool according to a fifth embodiment of the present invention, and (b) is a cross-sectional front view thereof. BEST MODE FOR CARRYING OUT THE INVENTION

A first embodiment of the present invention will be described with reference to the drawings. In this embodiment, Shows the case where the coating film applied to the surface of the construction surface s is removed.However, the processing object of the present invention is not limited thereto. It can be widely applied for removing and processing construction surfaces made of other "coats" or other materials.

 The rotating tool T shown in FIGS. 1 to 4 includes a rotating body 10 made of a metal plate and a plurality of blades 20 attached to the rotating body 10.

 The rotating body 10 integrally has a flat outer peripheral portion 11 and an inner portion 12 formed inside the outer peripheral portion 11.

 The inner portion 12 bulges upward from the inner edge of the outer peripheral portion 11 in a substantially truncated cone shape, and a flat plate portion 14 parallel to the outer peripheral portion 11 is formed in the center portion. A drive shaft through hole 18 is formed in the center of the flat plate portion 14, and a drive shaft of a drive source (not shown) is mounted in the through hole 18, so that the drive shaft and the drive shaft are integrally rotated. The entire tool is driven to rotate around the center axis 〇 (Fig. 2). Further, a plurality of through holes 17 arranged in the circumferential direction are formed in a bulged portion outside the flat plate portion 14 in the radial direction of rotation (ie, a portion between the rotation center axis 0 and the outer peripheral portion 11). Have been.

 The bottom surface of the outer peripheral portion 11 is a surface (hereinafter, simply referred to as “opposed surface”) that is disposed so as to face in parallel with the construction surface S as shown in FIG. A plurality of blade portions 20 are arranged on the surface in the circumferential direction. In the illustrated example, eight blade portions 20 are arranged at equal intervals in the circumferential direction, and are fixed to the facing surface by means such as brazing or screwing.

 Each blade portion 20 includes a blade portion main body 22 and a hard sintered body 24 partially fixed to the blade portion main body 22 via a cemented carbide 23.

The blade main body 22 is formed in a block shape by hardening abrasive grains (for example, diamond abrasive grains or CBN abrasive grains) with a metal binder (for example, iron, cono-nort, or tungsten). In the example shown in the figure, an outer peripheral surface having an arc shape in bottom view along the outer peripheral edge of the outer peripheral portion 11 is provided. It has an arc-shaped inner peripheral surface along the inner peripheral edge of the portion 11 and both side surfaces that are linear in a bottom view and extend in the radial direction of the tool T, and the whole has a uniform thickness dimension. The blade main body 22 has a shape in which a portion on the downstream side in the rotational direction and an outer portion in the radial direction of rotation is locally notched, and the notched portion has a shape supplementing the notched portion. 23 and the hard sintered body 24 are fixed.

 The hard sintered body 24 may be made of a sintered body that is harder than the blade main body 22, and may be, for example, a cemented carbide, ceramics, cermet, or the like, but is particularly excellent in hardness. A polycrystalline diamond sintered body and a polycrystalline cubic boron nitride sintered body having the second highest hardness are preferred. As a method of manufacturing such a hard sintered body 24 and fixing it to the blade main body 22, for example, the raw material of the hard sintered body 24 is provided on the surface of a substrate made of the cemented carbide 23. A diamond sintered body tool material is produced by placing a diamond powder on the body and applying pressure to sinter the whole to form a diamond sintered body tool material.The tool material is cut into a shape corresponding to the cutout portion of the blade body 22. It is preferable to use a method in which the surface of the cemented carbide 23 is fixed to the blade main body 22 by mouth.

 With the hard sintered body 24 fixed to the blade main body 22, the lower edge 24 of the hard sintered body 24 on the downstream side in the rotational radius direction and the downstream side in the rotary radial direction of the blade main body 22 are And the lower edge 2 2 a of the blade body 2 2 are aligned with each other. a constitutes the inner portion of the cutting edge in the radial direction of rotation.

 In the example shown in the figure, the blade edge angle is 90 ° and the rake angle is 0 °, but these angles may be appropriately set according to the specific material and use of the blade portion.

The ratio of the length Ls of the lower edge 24a to the total length L0 of the cutting edge as shown in FIG. 1 depends on the material of the hard sintered body 24. In the case of a diamond sintered body or a polycrystalline cubic boron nitride sintered body, the content is preferably 1% to 67%. If it is less than 1%, there is a high possibility that image sticking will occur. Inconvenience due to the notch is likely to occur.

 The thickness of the hard sintered body 24 may be smaller than the thickness of the blade main body 22. However, by making the thicknesses equal, the life of the blade 20 can be maximized. Next, the operation and operation of the tool T will be described.

 1) Mounting on drive machine

 First, the tool T is mounted on the drive. FIG. 4 shows a hand-held type driving device 30 as an example. The drive unit 30 has a gripper 32 and a tool cover 36 provided at the tip thereof. A drive shaft (not shown) protrudes into the tool cover 36, and the drive shaft is connected to the drive cover 30. A motor or the like that rotates at a high speed is built in the drive body. The inside of the tool cover 36 is connected to an unillustrated air pump via an air pipe 34. The drive shaft of the drive unit 30 is passed through the drive shaft through hole 18 of the tool T, and the rotating body 10 is driven by attaching a nut to a male screw portion formed at the tip of the drive shaft. Connect to the shaft end and fix. As a result, the entire tool T is mounted in the tool cover 36 shown in FIG. 4 and is covered by the tool cover 36 from the back side (the side opposite to the construction surface S).

 2) Construction with tool T

 The drive shaft and the tool T are integrally rotated at a high speed (that is, rotated around an axis perpendicular to the facing surface), and while the inside of the tool cover 36 is evacuated by an exhaust pump (not shown), The gripper 32 of the drive unit 30 is gripped, and each cutting tool 20 is pressed against a construction surface (for example, a wall surface) S, and scanning is performed along the construction surface S. As a result, the cutting edge of each of the high-speed rotating cutting tools 20 thinly removes the coating film on the construction surface S.

Here, the outer part in the rotational radius direction of the cutting edge, i.e., the part having a high rotational speed and a large amount of cutting work, is composed of a sharply hardened sintered body 24. The coating film on the surface S can be removed at a high speed and shallowly, and seizure due to thermal fusion of the coating film can be prevented. On the other hand, the inner part in the radial direction of rotation, The portion having a low rotational circumferential speed and a small amount of cutting work is made of a metal binder grindstone having a lower hardness than the sintered body and a relatively dullness (a grindstone constituting the blade body 22). Therefore, it is possible to prevent the entire cutting edge from biting too deeply.

 Further, as described above, the outer portion in the rotating radial direction having a large amount of cutting work at the cutting edge is formed of the hard sintered body 24, while the inner portion in the rotating radial direction having a relatively small amount of cutting work is formed of the grinding stone (the blade body). The wear speed of the cutting edge can be made uniform over the radial direction of rotation, and unlike the conventional one, the entire cutting edge is made of the same material. It is possible to prevent the outer part in the rotational radius direction of the cutting edge from being worn before the inner part in the radial direction of rotation (so-called "sagging"), thereby maintaining the life of the cutting edge longer.

 Further, removal processing by a cutting edge composed of the lower surface 24 a of the hard sintered body 24 (hereinafter referred to as “hard sintered body cutting edge 24 a”) is performed by the blade main body made of the whetstone. It is possible to assist with the cutting edge composed of 22 (hereinafter referred to as “grinding stone cutting edge 2 2a”). For example, when this tool is used for removing the coating film, the coating film that could not be removed with the hard sintered body cutting edge 24a can be auxiliary removed by the whetstone cutting edge 22a. Further, when a scratch is generated by the removal processing using the hard sintered body cutting edge 24a, an effect of reducing or eliminating the scratch by the grinding stone cutting edge 22a is expected.

 Chips generated by such stripping are sucked toward the tool cover 36 (the side opposite to the construction surface S) through the through holes 17.

By the way, FIGS. 1 to 4 show a mode in which a tool T is mounted on a hand-held type driving machine 30 and used. However, the present invention is not limited to this. In this case, it is possible to efficiently remove the paint film in a comfortable posture by attaching the tool T to a hand-operated processing machine or a riding-type processing machine that can travel on the floor. Fig. 5 shows an example of the tool T for that purpose. In the illustrated rotating tool T, the rotating body 10 Is formed in a simple disk shape, and a plurality of blade portions 20 are arranged on an outer peripheral portion thereof. In the illustrated blade portion 20, the blade portion main body 22 is formed in a triangular shape when viewed from the bottom. 1 to 4 are exactly the same as those shown in FIG.

 The construction surface to be constructed according to the present invention is not limited to the walls and floors of buildings, and the present invention can be effectively applied to, for example, painting and repair of ships and bridges.

 Further, in the illustrated blade portion 20, the metal binder whetstone forming the inner portion in the rotation radial direction of the blade edge forms the blade portion main body 22 as it is. However, the present invention is not limited to this. Is composed of a different material (such as a cemented carbide). The blade body contains a hard sintered body that constitutes the outer part of the cutting edge in the radial direction of rotation and a grindstone (abrasive grains that constitute the inner part of the cutting edge in the radial direction of rotation). It is also possible to fix side by side with a grindstone fixed with a binder.

 In the present invention, a plurality of blade portions may be disposed on the opposing surface in an inner or outer double or multiple (ie, on a plurality of concentric circles).

 Further, in the rotary tool according to the present invention, not all the blade portions need to have both the grindstone cutting edge 22 a and the hard sintered body cutting edge 24 a like the blade portion 20. A first blade portion including at least a hard sintered body blade, and a second blade portion whose entire blade edge is formed of a grindstone in which abrasive grains are hardened with a metal binder are provided on an opposed surface in a mixed manner. A little.

For example, as shown in FIG. 6 and FIG. 7 as a second embodiment, a blade portion (first blade portion) 20 having both the above-mentioned grindstone blade tip 22 a and a hard sintered body 24 a is provided with a peripheral portion. The blade section (the second section) which is arranged intermittently in the direction and has only a cutting edge 26 a formed between the blade sections 20 and composed of the above-mentioned grindstone (a grindstone in which abrasive grains are bonded by a metal binder). (2 blades) 26 may be interposed. Further, as shown in FIGS. 8 and 9 as the third embodiment, as shown in FIGS. 8 and 9, the circumcircle C of the cutting edge 26 a of the blade portion 26 is larger than that of the hard sintered body cutting edge 24 a of the blade portion 20. If it is located inside the rotating body 10 in the radial direction of rotation, each blade 26 It is possible to reduce the load on the cutting edge 22 a made of whetstone in each blade portion 20. That is, as shown in FIG. 10 as the fourth embodiment, a blade portion having only a hard sintered body blade edge 24 a was provided at a position outside the blade portion 26 in the rotation radial direction. (In the illustrated example, the blade portion made of the hard sintered body 24 is fixed in the concave groove 16 formed on the opposing surface of the rotating body 10). In other words, the grindstone cutting edge shown in FIG. Even with the configuration in which 22 a is omitted, excessive cutting is suppressed by the cutting edge 26 a of the blade portion 26 made of the whetstone, and the cutting action by the cutting edge 24 a and the cutting It is possible to reduce or eliminate the generated scratches.

 Further, as a fifth embodiment, as shown in FIG. 11, a grinding wheel 28 having a shape (a ring shape in the figure) continuous in the rotating circumferential direction of the rotating body 10 is provided. The rotary tool may be provided with a cutting part having a cutting edge 24 a made of a hard sintered body at a position outside the rotating body 10 in the rotating radial direction. Thus, even when the grindstone 28 does not have a cutting edge, it is possible to assist the cutting by the hard sintered body cutting edge 24a by its grinding action. It is possible to reduce or eliminate scratches caused by cutting with 24a by grinding with the grinding wheel 28. Of course, the effect of preventing excessive cutting can be enjoyed.

 However, as in the first embodiment, if all the blades are configured by the blades according to the present invention and the blades are arranged at equal intervals in the circumferential direction, the cutting performance is improved. Can be made uniform in the circumferential direction, and an advantage that smoother removal processing and a longer tool life can be realized can be obtained.

Claims

The scope of the claims 1. A rotary tool provided with a rotating body having an opposing surface facing the construction surface is provided on the opposing surface, and the rotating body is driven to rotate about an axis perpendicular to the opposing surface. The blade of a rotary tool that has a cutting edge that removes the surface of the construction surface when pressed against the construction surface, and the inside of the cutting edge in the radial direction of rotation is a grindstone that combines abrasive grains with a metal binder. A blade portion of a rotary tool, wherein a portion of the blade edge in a rotation radial direction outside is formed of a sintered body harder than the grindstone.  2. The blade portion of the rotary tool according to claim 1, wherein an outer portion in the rotation radial direction of the blade edge is made of a polycrystalline diamond sintered body or a polycrystalline cubic boron nitride sintered body. Blade part of rotating tool.  3. The blade portion of the rotary tool according to claim 1, wherein the entire blade portion excluding the blade tip portion formed of the sintered body is formed of a grindstone in which abrasive grains are bonded by a metal binder. A feature of rotating tool blades.  4. The cutting edge of the rotary tool according to claim 1, wherein a length of the cutting edge made of the sintered body is set in a range of 1% to 67% of a total length of the cutting edge. The blade part of the rotating tool. 5. A rotating body having an opposing surface facing the construction surface, and a plurality of blade portions provided side by side on the opposing surface and having a cutting edge for removing a surface portion of the construction surface in a rotational circumferential direction, A rotating tool for rotating the rotating body about an axis perpendicular to the facing surface and pressing each blade portion against the working surface to remove a surface portion of the working surface; A grindstone in which abrasive grains are bonded to the surface with a metal binder is provided, and the cutting edge of the blade portion includes a cutting edge made of a sintered body harder than the grinding stone. The rotary tool, wherein the cut edge is provided at a position radially outward of the rotating body from the grinding stone. 6. The rotating tool according to claim 5, wherein the cutting edge of the blade portion includes a cutting edge formed of the grindstone, and a cutting edge formed of a sintered body harder than the grindstone, A rotating tool, wherein the blades are arranged such that a blade made of the sintered body is located outside of the rotating body in the radial direction of rotation of the rotating body with respect to a blade made of the whetstone. .  7. The rotating tool according to claim 5, wherein the grindstone has a shape that is continuous in a rotating circumferential direction of the rotating body, and at a position radially outward of the rotating body relative to the grinding stone, A rotary tool comprising a blade portion having a blade edge made of the sintered body.  8. A rotating body having an opposing surface facing the construction surface, and a plurality of blade portions provided side by side on the opposing surface and having a cutting edge for removing a surface portion of the construction surface in a circumferential direction of rotation. A rotating tool that removes a surface portion of the construction surface by pressing each blade portion against the construction surface while the rotating body is rotationally driven around an axis in a direction orthogonal to the facing surface; A rotary tool, characterized in that at least a part of the blade portion is constituted by the blade portion according to any one of claims 1 to 4.  9. The rotary tool according to claim 8, wherein all the blades are constituted by the blades according to any one of claims 1 to 4, and the blades are equally spaced in a circumferential direction. A rotary tool, wherein the rotary tool is disposed.  10. The rotary tool according to claim 8, wherein at least a first blade portion having a cutting edge made of the sintered body and a second blade portion having a cutting edge made of the whetstone are provided. And the second blade portion is disposed such that the blade edge of the second blade portion is located on the rotation radial direction inner side of the rotating body with respect to the blade edge formed of the sintered body in the first blade portion. A rotary tool characterized by being made.