Holder, cutting tool, and method for producing cut workpiece

Abstract

A holder according to a non-limiting aspect of the present disclosure comprises a body that is columnar and extends from a first end to a second end along a rotational axis. The body comprises an end surface positioned on the first end side, an outer peripheral surface, a plurality of pockets opening on the end surface and the outer peripheral surface, and a flow path through which a coolant flows. The flow path comprises a linear first flow path extending toward the outer peripheral surface, and a linear second flow path extending from the first flow path toward the outer peripheral surface. The flow paths are provided with a protruding section that is positioned at a connection part between the first flow path and the second flow path and protrudes from the second flow path toward the central axis of the first flow path.

Description

Holder, cutting tool, and method for manufacturing machined product CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Japanese Patent Application No. 2023-044064, filed on March 20, 2023, the entire disclosure of which is incorporated herein by reference.

[0002] The present disclosure generally relates to a holder and a cutting tool used in cutting a workpiece, and a method for manufacturing a machined product, and more particularly to a cutting tool used in milling.

[0003] Milling cutters and the like are known as cutting tools used to cut workpieces such as metals. Known examples of such cutting tools include those described in International Publication No. 2016 / 121870 (Patent Document 1) and Japanese Patent Laid-Open Publication No. 2018-86716 (Patent Document 2).

[0004] The cutting tool described in Patent Document 1 includes a holder and an insert. The holder has a pocket, a first flow path located therein, and an outlet located in the pocket. Coolant flows through the first flow path. The coolant flows through the first flow path toward the outlet. The pocket also has a mounting portion where the insert is located, and a cutout portion adjacent to the mounting portion and located forward of the mounting portion in the direction of rotation. The cutout portion has a recess. The coolant is sprayed toward the recess.

[0005] The cutting tool described in Patent Document 2 includes a holder and an insert. The holder has a pocket in which the insert is located and an outlet located in the pocket. The pocket has a first surface facing the side surface of the insert on the outer periphery of the holder. The first surface has a first groove through which a coolant flows.

[0006] A non-limiting one-sided holder of the present disclosure includes a columnar body extending from a first end to a second end along a rotation axis. The body includes an end face located on the first end side, an outer circumferential surface, a plurality of pockets opening to the end face and the outer circumferential surface, and a flow path through which a coolant flows. The flow path includes a first flow path having a linear shape extending toward the outer circumferential surface, and a second flow path having a linear shape extending from the first flow path toward the outer circumferential surface. The flow path includes a protrusion located at a connection portion between the first flow path and the second flow path, protruding from the second flow path toward the central axis of the first flow path.

[0007] 1 is a perspective view showing one surface of a holder (cutting tool) of the present disclosure, which is not limited thereto. FIG. 1 is an enlarged view of region II shown in FIG. 1. FIG. 1 is an enlarged view of the vicinity of a pocket in the holder (cutting tool) shown in FIG. 1, and is a see-through view of the flow paths and the like. FIG. 1 is a plan view of the holder (cutting tool) shown in FIG. 1, seen from the first end side. FIG. 1 is the same plan view as FIG. 4, and is a see-through view of the flow paths. FIG. 1 is an enlarged view of region VI shown in FIG. 4. FIG. 5 is an enlarged view of a portion of the holder (cutting tool) shown in FIG. 5. FIG. 7 is a cross-sectional view of section VIII in the holder (cutting tool) shown in FIG. 7, which includes the central axis of the first flow path. FIG. 8 is a cross-sectional view of section IX in the holder (cutting tool) shown in FIG. 7, which includes the central axis of the second flow path. FIG. 11 is a perspective view of the holder (cutting tool) shown in FIG. 1, seen from a different direction, and is a partially enlarged see-through view of the flow paths. FIG. 12 is a cross-sectional view of section XI in the holder (cutting tool) shown in FIG. 10, which includes the central axes of the first flow path and the second flow path. 12 is a plan view of the holder shown in FIG. 1 as seen from the first end side, and is a view seen through the flow path. FIG. 12 is an enlarged view of region XIII shown in FIG. 12. FIG. 13 is a perspective view of a cutting insert in the cutting tool shown in FIG. 1. FIG. 14 is a perspective view of the cutting insert shown in FIG. 14 as seen from another direction. FIG. 15 is a cross-sectional view showing a non-limiting one-sided holder (cutting tool) of the present disclosure, and is a view corresponding to FIG. 11. FIG. 16 is a schematic view showing one step in a non-limiting method for manufacturing a one-sided machined product of the present disclosure. FIG. 17 is a schematic view showing one step in a non-limiting method for manufacturing a one-sided machined product of the present disclosure. FIG. 18 is a schematic view showing one step in a non-limiting method for manufacturing a one-sided machined product of the present disclosure.

[0008] <Holder> A non-limiting example of the holder 1 of the present disclosure will be described in detail below with reference to the drawings. However, for the sake of convenience, the figures referred to below show only the main components necessary for explaining the embodiment in a simplified form. Therefore, the holder 1 may include optional components not shown in the figures referred to. Furthermore, the dimensions of the components in the figures do not faithfully represent the actual dimensions of the components or the dimensional ratios of the components.

[0009] The holder 1 may include a main body 3, as shown in Figures 1 to 13 as a non-limiting example. The main body 3 may be a columnar body extending from a first end 3a to a second end 3b along the rotation axis O1, as shown in Figure 1 as a non-limiting example. In general, the first end 3a is referred to as the "front end" and the second end 3b is referred to as the "rear end."

[0010] The main body 3 is rotatable around a rotation axis O1. Note that the arrow Y1 in Fig. 1 and other figures may indicate the rotation direction of the rotation axis O1, or may indicate the rotation direction of the main body 3 around the rotation axis O1.

[0011] The main body 3 may be a cylindrical body. Note that the cylindrical body may be a roughly cylindrical body, and does not necessarily have to be a cylindrical body in the strict sense.

[0012] The size of the main body 3 is not limited to a specific size. For example, the length of the main body 3 in the direction along the rotation axis O1 may be set to approximately 30 to 80 mm. Furthermore, the width (diameter) of the main body 3 in the direction perpendicular to the rotation axis O1 may be set to approximately 20 to 400 mm.

[0013] 2 , the main body 3 may include an end surface 5 located on the first end 3a side and an outer circumferential surface 7. The main body 3 may also include a plurality of pockets 9. Each of the plurality of pockets 9 may open to the end surface 5 and the outer circumferential surface 7. A cutting insert can be attached to each of the plurality of pockets 9.

[0014] The pockets 9 may be positioned at equal intervals around the rotation axis O1, or may be positioned at uneven intervals. The number of pockets 9 may be about 2 to 40.

[0015] The main body 3 may include a flow path 11 through which the coolant flows, as shown in a non-limiting example in Fig. 5. The flow path 11 may be located inside the main body 3. The flow path 11 may have, for example, a circular, elliptical, or polygonal shape in a cross section perpendicular to the direction in which the coolant flows. The inner diameter of the flow path 11 may be set to, for example, about 0.5 to 5 mm.

[0016] The flow path 11 may include a first flow path 13 and a second flow path 15, as shown in a non-limiting example in FIG.

[0017] The first flow passage 13 may extend toward the outer circumferential surface 7. The first flow passage 13 may also have a linear shape.

[0018] The second flow passage 15 may extend from the first flow passage 13 toward the outer peripheral surface 7. In other words, the second flow passage 15 may branch off from the first flow passage 13 and extend toward the outer peripheral surface 7. In this case, a portion of the coolant flowing through the first flow passage 13 may flow into the second flow passage 15. The second flow passage 15 may also have a linear shape.

[0019] Here, the flow path 11 may include a protrusion 17, as in a non-limiting example shown in Fig. 11 . The protrusion 17 may be located at a connection portion 19 between the first flow path 13 and the second flow path 15. The protrusion 17 may also protrude from the second flow path 15 toward the central axis O2 of the first flow path 13. In these cases, the protrusion 17 makes it possible to increase the amount of coolant flowing into the second flow path 15. Therefore, with the holder 1, when the flow paths 11 through which the coolant flows, formed within the holder 1, branch, it is possible to adjust the amount of coolant flowing into each of the flow paths 11.

[0020] 11 , in a cross section including the central axis O2 of the first flow passage 13 and the central axis O3 of the second flow passage 15, at least a portion of the protrusion 17 may be located outside the connecting portion 19. In other words, in the cross section, at least a portion of the protrusion 17 may be located at the outermost portion of the connecting portion 19. In this case, the protrusion 17 is likely to increase the amount of coolant flowing into the second flow passage 15. Note that the term "outside" may refer to the side away from the rotation axis O1. In addition, the central axis O2 of the first flow passage 13 may be referred to as the first central axis O2, and the central axis O3 of the second flow passage 15 may be referred to as the second central axis O3.

[0021] The protruding portion 17 may be referred to as a protrusion. The protruding portion 17 does not have to protrude beyond the central axis O2 of the first flow passage 13. That is, the tip 17a of the protruding portion 17 may be located closer to the connection portion 19 than the central axis O2 of the first flow passage 13. In this case, it is easy to avoid an excessive amount of coolant flowing into the second flow passage 15.

[0022] The protruding portion 17 may protrude along the extension direction of the second flow path 15. In other words, the protruding portion 17 may protrude along the central axis O3 of the second flow path 15.

[0023] The protrusion 17 may be formed integrally with the main body 3. For ease of visual understanding, in the non-limiting example shown in Fig. 11, the protrusion 17 is hatched differently from the main body 3. This also applies to Fig. 16, which will be described later.

[0024] The connecting portion 19 may be referred to as a branch port. The connecting portion 19 may be ring-shaped. The protrusion 17 may be located around the entire circumference of the ring-shaped connecting portion 19, or may be located partially around the circumference.

[0025] There is no particular limitation on the method for processing the flow channel 11. For example, a method using a tool such as a drill, a method using a 3D printer, or the like can be mentioned.

[0026] 7 and 13 , the pocket 9 may have a first pocket 21 and a second pocket 23. The first flow passage 13 may open at the first pocket 21. The second flow passage 15 may open at the second pocket 23. The openings of the first flow passage 13 and the second flow passage 15 in the pocket 9 may function as outlets for allowing the coolant to flow out.

[0027] 8, the first flow passage 13 may extend from the second end 3b toward the first pocket 21. Alternatively, the first flow passage 13 may be inclined so as to approach the first end 3a as it approaches the first pocket 21 (outer peripheral surface 7).

[0028] 8, the first flow passage 13 may also open on the side of the rotation axis O1 of the main body 3. This opening can function as an inlet for allowing coolant to flow into the inside of the first flow passage 13. The position of this opening is not particularly limited.

[0029] The inner diameter of the second flow passage 15 may be the same as the inner diameter of the first flow passage 13. In this case, it is possible to adjust the amount of coolant using only the protrusion 17. Furthermore, the first flow passage 13 and the second flow passage 15 can be machined using the same tool, making it easy to manufacture the holder 1.

[0030] Note that the inner diameter of the second flow path 15 being the same as the inner diameter of the first flow path 13 does not necessarily mean that the two values ​​are exactly the same. For example, there may be a difference of about 10% between the two values. Furthermore, the inner diameters of the two are not necessarily the same. They may be different. The inner diameters of the first flow path 13 and the second flow path 15 may be constant.

[0031] 7 and 13, the second pocket 23 may be adjacent to the first pocket 21 at the rear in the rotation direction Y1 of the rotation axis O1. In this case, the length of the second flow path 15 can be easily shortened. Therefore, the thickness of the main body 3 between the first pocket 21 and the second pocket 23 can be easily ensured. Therefore, the durability of the holder 1 is high.

[0032] Examples of materials that can be used for the main body 3 include aluminum alloy, steel, and cast iron. When the main body 3 is made of steel, the main body 3 has high toughness.

[0033] Examples of coolants include water-insoluble oils and water-soluble oils. Examples of water-insoluble oils include cutting oils such as oil-based, inert extreme pressure, and active extreme pressure types. Examples of water-soluble oils include cutting oils such as emulsions, solubles, and solutions. The coolant is not limited to a liquid, but may be a gas such as an inert gas. The coolant may also be referred to as a cooling fluid. The coolant may be appropriately selected and used depending on the material of the workpiece.

[0034] Next, another non-limiting aspect of the holder 1A of the present disclosure will be described with reference to the drawings. Below, differences between the holder 1A and the holder 1 will be mainly described, and detailed descriptions of the same configurations as the holder 1 may be omitted. Therefore, the description of the holder 1 may be used to understand the configuration of the holder 1A.

[0035] 16 , in the holder 1A, in a cross section including the central axis O2 of the first flow passage 13 and the central axis O3 of the second flow passage 15, at least a portion of the protrusion 17 may be located inside the connecting portion 19. In other words, in the cross section, at least a portion of the protrusion 17 may be located at the innermost portion of the connecting portion 19. In this case, the protrusion 17 can easily increase the amount of coolant flowing into the second flow passage 15. Note that the inside may mean the side closer to the rotation axis O1.

[0036] <Cutting Tool> Next, a non-limiting one-sided cutting tool 101 according to the present disclosure will be described with reference to the drawings, taking as an example a case where the cutting tool 101 includes the holder 1 described above.

[0037] 1 to 15, the cutting tool 101 may include a holder 1 and a cutting insert 103. When the cutting tool 101 includes the holder 1, it is possible to adjust the amount of coolant flowing through the branched flow paths 11, and therefore, excellent cutting performance can be exhibited. The cutting tool 101 may also be used for milling.

[0038] The cutting insert 103 may be simply referred to as the insert 103. The insert 103 can be used to cut a workpiece in a cutting process.

[0039] There may be a plurality of inserts 103. That is, the cutting tool 101 may include a plurality of inserts 103. The plurality of inserts 103 may be positioned in a plurality of pockets 9. The number of inserts 103 may be the same as the number of pockets 9.

[0040] The insert 103 may be a columnar body, as shown in a non-limiting example in Figures 14 and 15. The insert 103 may also have a cutting edge 105. The cutting tool 101 can perform cutting by bringing the cutting edge 105 of the insert 103 into contact with a workpiece.

[0041] 2, the insert 103 may be positioned in the pocket 9 so that at least a portion of the cutting edge 105 protrudes from the holder 1. The cutting edge 105 may have a first cutting edge 107 located on the first end 3a side and a second cutting edge 109 located on the outer periphery side. Note that the outer periphery side may mean the side away from the rotation axis O1.

[0042] 7, the insert 103 may include a first insert 111 and a second insert 113. The first insert 111 may be located in the first pocket 21. The second insert 113 may be located in the second pocket 23.

[0043] The first flow passage 13 may extend toward a side surface 115 of the first insert 111 that faces the main body 3, as in a non-limiting example shown in Fig. 8. The second flow passage 15 may extend toward the cutting edge 105 of the second insert 113, as in a non-limiting example shown in Fig. 9. In these cases, it is possible to appropriately supply coolant to the required location.

[0044] The material of the insert 103 may include, for example, cemented carbide, cermet, ceramics, PCD (polycrystalline diamond), and cBN (cubic boron nitride).

[0045] Cemented carbide compositions may include, for example, WC—Co, WC—TiC—Co, and WC—TiC—TaC—Co, where WC, TiC, and TaC may be hard particles and Co may be a binder phase.

[0046] The cermet may be a sintered composite material in which a ceramic component is combined with a metal. An example of a cermet is a titanium compound mainly composed of titanium carbide (TiC) or titanium nitride (TiN). It goes without saying that the material of the insert 103 is not limited to the above composition.

[0047] The insert 103 may be made of only one member, or may be made of multiple members. When the insert 103 is made of multiple members, the member where the cutting edge 105 is located may be made of a material with a relatively high hardness, such as PCD or cBN. Furthermore, the member where the cutting edge 105 is not located may be made of, for example, cemented carbide, cermet, ceramics, or the like.

[0048] The surface of the insert 103 may be coated with a coating using a chemical vapor deposition (CVD) or physical vapor deposition (PVD) method, and the coating composition may include, for example, titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), and alumina (AlO).

[0049] The cutting tool 101 may include a fixing member 117, as shown in a non-limiting example in Fig. 1 . The fixing member 117 may be a member for fixing the insert 103 to the holder 1. The number of fixing members 117 may be the same as the number of inserts 103. The fixing member 117 may be a screw, as shown in a non-limiting example in Fig. 1 . Note that the fixing member 117 is not limited to a screw.

[0050] In a non-limiting example shown in Fig. 1, cutting tool 101 includes holder 1, but is not limited to such a form. As a non-limiting example shown in Fig. 16, cutting tool 101A may include holder 1A.

[0051] <Method for Manufacturing Machined Product> Next, a non-limiting method for manufacturing the machined product 201 having one surface according to the present disclosure will be described with reference to the drawings.

[0052] The machined product 201 may be produced by cutting the workpiece 203. The manufacturing method of the machined product 201 may include the following steps: (1) a step of rotating the cutting tool 101 typified by the non-limiting embodiment described above; (2) a step of bringing the rotating cutting tool 101 into contact with the workpiece 203; and (3) a step of separating the cutting tool 101 from the workpiece 203.

[0053] Specifically, first, as shown in a non-limiting example in Fig. 17 , the cutting tool 101 may be rotated around the rotation axis O1 and moved relatively close to the workpiece 203. Next, as shown in a non-limiting example in Fig. 18 , the cutting edge 105 of the insert 103 in the cutting tool 101 may be brought into contact with the workpiece 203 to cut the workpiece 203. Then, as shown in a non-limiting example in Fig. 19 , the cutting tool 101 may be moved in a direction relatively away from the workpiece 203.

[0054] By going through the above steps, it is possible to obtain a machined product 201 with a highly accurate finished surface. Specifically, in the manufacturing method of the machined product 201, when the cutting tool 101 including the holder 1 is used, it is possible to adjust the amount of coolant flowing into the branched flow paths 11, and therefore it is possible to exhibit excellent workability. As a result, it is possible to obtain a machined product 201 with a highly accurate finished surface.

[0055] In the non-limiting example shown in FIGS. 17 to 19, the workpiece 203 is fixed and the cutting tool 101 is moved in each step, but the present invention is not limited to this configuration.

[0056] For example, in step (1), the workpiece 203 may be brought closer to the cutting tool 101. In step (3), the workpiece 203 may be moved away from the cutting tool 101. When continuing the cutting process, the cutting tool 101 may be kept rotating, and the step of bringing the cutting tool 101 into contact with different locations of the workpiece 203 may be repeated.

[0057] Examples of the material of the workpiece 203 include aluminum alloy, carbon steel, alloy steel, stainless steel, cast iron, and non-ferrous metals.

[0058] 17 to 19, a cutting tool 101 including a holder 1 is used, but the present invention is not limited to this. For example, a cutting tool 101A including a holder 1A may be used.

[0059] The above provides examples of the non-limiting one-sided holder 1, 1A, cutting tool 101, 101A, and method for manufacturing the machined product 201 of the present disclosure, but it goes without saying that the present disclosure is not limited to the above embodiments and can be any as long as it does not deviate from the gist of the present disclosure.

[0060] For example, in the above embodiment, the first flow passage 13 opens in the first pocket 21, and the second flow passage 15 opens in the second pocket 23, but the first flow passage 13 and the second flow passage 15 are not limited to opening in the pocket 9. The first flow passage 13 and / or the second flow passage 15 may open in a region of the outer circumferential surface 7 other than the pocket 9, for example.

[0061] Furthermore, the manufacturing method of the holder 1, 1A, the cutting tool 101, 101A, and the machined product 201 may be configured as follows. (1) The holder includes a columnar main body extending from a first end to a second end along a rotation axis, the main body including an end face located on the first end side, an outer circumferential surface, a plurality of pockets opening to the end face and the outer circumferential surface, and a flow path through which a coolant flows, the flow path including a first flow path having a linear shape extending toward the outer circumferential surface and a second flow path having a linear shape extending from the first flow path toward the outer circumferential surface, the flow path including a protrusion located at a connection portion between the first flow path and the second flow path and protruding from the second flow path toward a central axis of the first flow path. (2) In the holder described in (1) above, at least a part of the protrusion may be located outside the connection portion in a cross section including the central axis of the first flow path and the central axis of the second flow path. (3) In the holder of (2) above, at least a portion of the protrusion may be located more inward than the connecting portion in the cross section. (4) In the holder of any one of (1) to (3) above, the pocket may have a first pocket and a second pocket, the first flow path may open in the first pocket, and the second flow path may open in the second pocket. (5) A cutting tool may include the holder of any one of (1) to (4) above and a plurality of cutting inserts positioned in the plurality of pockets. (6) In the cutting tool of (5) above, the pocket may have a first pocket and a second pocket, the first flow path may open in the first pocket, and the second flow path may open in the second pocket, and the cutting inserts may include a first cutting insert positioned in the first pocket and a second cutting insert positioned in the second pocket, the first flow path may extend toward a side surface of the first cutting insert facing the body, and the second flow path may extend toward a cutting edge of the second cutting insert. (7) A method for manufacturing a machined product can include the steps of rotating the cutting tool described above in (5) or (6), bringing the rotating cutting tool into contact with a workpiece, and removing the cutting tool from the workpiece.

[0062] DESCRIPTION OF SYMBOLS 1...Holder 3...Main body 3a...First end 3b...Second end 5...End face 7...Outer peripheral surface 9...Pocket 11...Flow path 13...First flow path 15...Second flow path 17...Protrusion 17a...Tip 19...Connecting portion 21...First pocket 23...Second pocket 101...Cutting tool 103...Cutting insert (insert) 105...Cutting edge 107...First cutting edge 109...Second cutting edge 111...First cutting insert (first insert) 113...Second cutting insert (second insert) 115...Side surface 117...Fixed member 201...Cutted workpiece 203...Workpiece O1...Rotation axis O2...Central axis (first central axis) O3...Central axis (second central axis) Y1...Rotation direction

Claims

1. a cylindrical body extending from a first end to a second end along a rotation axis; The body includes: an end surface located on the first end side; The outer surface, a plurality of pockets opening to the end surface and the outer circumferential surface; a flow path through which the coolant flows; The flow path is a first flow path having a linear shape extending toward the outer circumferential surface; a second flow path having a linear shape extending from the first flow path toward the outer circumferential surface, The flow path includes a protrusion located at a connection portion between the first flow path and the second flow path, the protrusion protruding from the second flow path toward a central axis of the first flow path.

2. In a cross section including the central axis of the first flow path and the central axis of the second flow path, The holder according to claim 1 , wherein at least a portion of the protrusion is located outside the connecting portion.

3. In the cross section, The holder according to claim 2 , wherein at least a portion of the protrusion is located inwardly of the connecting portion.

4. The pocket includes a first pocket and a second pocket, the first flow path opens at the first pocket; 4. The holder according to claim 1, wherein the second flow path opens in the second pocket.

5. A holder according to any one of claims 1 to 3; and a plurality of cutting inserts positioned in the plurality of pockets.

6. The pocket includes a first pocket and a second pocket, the first flow path opens at the first pocket; the second flow path opens at the second pocket; The cutting insert comprises: a first cutting insert located in the first pocket; a second cutting insert located in the second pocket; the first flow passage extends toward a side surface of the first cutting insert facing the body, The cutting tool of claim 5 , wherein the second channel extends toward a cutting edge of the second cutting insert.

7. rotating the cutting tool of claim 5; contacting the rotating cutting tool with a workpiece; and removing the cutting tool from the workpiece.