Cutting tool and method for manufacturing cut workpiece

Abstract

Provided is a cutting tool in which a clamper resists tilting and fixes an insert with higher precision. A cutting tool according to the present disclosure comprises a holder, a clamper, an insert, and a fixing member. The holder has a rod shape, and has a tip surface, a side surface, a first hole, a second hole, and a pocket. The clamper has a body part and a projection part. The body part has a slit that opens toward the second hole. The fixing member has a screw part and an abutting part capable of restraining the clamper by abutting on the clamper.

Description

Cutting tool and method for manufacturing machined product

[0001] The present disclosure relates to a cutting tool used when cutting a workpiece such as a metal, and a method for manufacturing a machined product.

[0002] 2. Description of the Related Art Conventionally, as an example of a method for fixing a cutting insert to a holder in an insert-type cutting tool, a lever-lock type clamping mechanism as described in Patent Documents 1 and 2 has been used.

[0003] The cutting tool described in Patent Document 2 has a structure in which an L-shaped clamper clamps an insert by operating a screw through a hole provided on the side (back) of the holder.

[0004] Japanese Unexamined Patent Publication No. 02-097504 Japanese Unexamined Patent Publication No. 2015-139839

[0005] A cutting tool according to one aspect of the present disclosure includes a rod-shaped holder extending from a front end to a rear end along a first central axis, an insert, a clamper, and a fixing member. The holder has a front end surface located on the front end side, a side surface adjacent to the front end surface, a first hole extending from the front end surface toward the rear end, a second hole extending from the side surface to the first hole, and a pocket located on the front end side and having a bottom surface parallel to the first central axis. The insert is located in the pocket and has a through hole. The clamper is capable of restraining the insert and includes a main body portion inserted into the first hole and a protrusion extending from the main body portion toward the insert and inserted into the through hole of the insert. The main body portion has a slit opening toward the rear end and the second hole. The fixing member is rod-shaped and extends along the second central axis, and has a threaded portion having a thread groove on its outer surface, and an abutment portion adjacent to the threaded portion, inserted into the slit, and abutting against the clamper to restrain the clamper.

[0006] 1 is a perspective view showing a cutting tool in a non-limiting embodiment of the present disclosure. FIG. 1 is an enlarged view of an area A1 shown in FIG. 1 , with the cutting tool disassembled. FIG. 2 is a view showing a holder and an insert in the enlarged view shown in FIG. 2. FIG. 3 is a side view of the cutting tool shown in FIG. 1 , as viewed from direction B1. FIG. 4 is a cross-sectional view taken along line V-V in FIG. 4. FIG. 1 is a side view of the cutting tool shown in FIG. 1 , as viewed from direction B2. FIG. 1 is a side view of the cutting tool shown in FIG. 1 , as viewed from direction B3. FIG. 3 is a perspective view of a clamper in a non-limiting embodiment of the present disclosure. FIG. 8 is a side view of the clamper shown in FIG. 8 , as viewed from direction C1. FIG. 9 is a cross-sectional view taken along line X-X in FIG. 9. FIG. 8 is a partial cross-sectional view of the clamper shown in FIG. 8. FIG. 11 is a partial cross-sectional view of the clamper shown in FIG. 11 , as viewed from another direction. FIG. 11 is a partial cross-sectional view of the clamper shown in FIG. 11 , as viewed from another direction. FIG. 12 is a side view of a fixing member in a non-limiting embodiment of the present disclosure. FIG. 13 is a simplified view showing a state in which the clamper is restrained by the fixing member in the present disclosure. FIG. 14 is a schematic view showing one step of a non-limiting example method for manufacturing a machined product in the present disclosure. Fig. 1 is a schematic diagram showing a step in a manufacturing method of a machined product as a non-limiting example in the present disclosure. Fig. 2 is a schematic diagram showing a step in a manufacturing method of a machined product as a non-limiting example in the present disclosure. Fig. 3 is a schematic diagram showing a step in a manufacturing method of a machined product as a non-limiting example in the present disclosure.

[0007] Hereinafter, a cutting tool 1 according to the present disclosure will be described in detail with reference to the drawings. Examples of cutting tools include turning tools and milling tools. Examples of turning tools include grooving tools and cut-off tools.

[0008] For convenience of explanation, the drawings referred to below show only the main components necessary for explaining the cutting tool 1 of the embodiment in a simplified form. Therefore, the cutting tool 1 of the present disclosure may include any components not shown in the drawings referred to. Furthermore, the dimensions of the components in the drawings do not faithfully represent the actual dimensions of the components and the dimensional ratios of each component. Furthermore, the present disclosure is not limited to the following aspects. Furthermore, in the following description, "A to B" indicating a numerical range means "greater than or equal to A and less than or equal to B" unless otherwise specified.

[0009] As shown in the example in FIGS. 1 to 3, the cutting tool 1 includes a holder 100, an insert 200, a clamper 300, and a fixing member 400.

[0010] <Holder> The holder 100 may be rod-shaped and extend along the first central axis L1 from the front end 100a to the rear end 100b. As an example shown in Figures 1, 4 and 6, the holder 100 may be square prism-shaped.

[0011] The size of the holder 100 is not particularly limited. For example, the length in the direction along the first central axis L1 can be set to approximately 50 mm to 250 mm. The maximum width in the direction perpendicular to the first central axis L1 can be set to approximately 3 mm to 50 mm.

[0012] Steel, cast iron, etc. may be used as the material of the holder 100. In particular, when steel is used among these materials, the toughness of the holder 100 is high.

[0013] 1 , the holder 100 may have a head 101 and a shank 103. The head 101 may be located on the front end 100a side of the holder 100. The shank 103 may be located on the rear end 100b side of the head 101.

[0014] The shank 103 may be a portion that is gripped by a machine tool when the cutting tool 1 is attached to the machine tool. On the other hand, the head 101 is a portion for gripping the insert 200, and has a pocket 109 (described later). The shank 103 generally has a simple cylindrical or prismatic shape. Therefore, the central axis of the shank 103 can be regarded as a first central axis L1 of the holder 100.

[0015] <Head> As an example shown in FIGS. 2 and 3 , the head 101 of the holder 100 may have a tip surface 105 , a side surface 107 , a pocket 109 , a first hole 111 and a second hole 113 .

[0016] The tip surface 105 may be located on the tip 100a side of the head 101. The tip surface 105 does not have to be formed by a single flat surface. For example, the tip surface 105 may be formed by a plurality of flat surfaces, as in the example shown in Figure 7, or may be formed by a curved surface.

[0017] 2 and 3, the pocket 109 may be located on the tip 100a side of the head 101. In this case, the pocket 109 may be configured by cutting out a portion of the head 101 on the tip 100a side. The pocket 109 may be adjacent to the tip surface 105, or may extend from the tip surface 105 toward the rear end 100b. An insert 200 can be attached to the pocket 109.

[0018] The pocket 109 may be aligned along the first central axis L1 or may be inclined in the vertical direction relative to the first central axis L1. Here, the inclination angle of the pocket 109 relative to the first central axis L1 may be, for example, approximately 0° to 60°.

[0019] The side surface 107 may be adjacent to the tip surface 105. The side surface 107 may be inclined with respect to the first central axis L1, or may be parallel to the first central axis L1, as in the example shown in FIGS. 1 to 6. The side surface 107 may also be composed of multiple flat surfaces. For example, as in the example shown in FIGS. 1 to 3, the side surface 107 may have an upper surface 107a located above, a lower surface 107b located below, a first side surface 107c to which a pocket 109 is connected, and a second side surface 107d located opposite the first side surface 107c. In the example shown in FIG. 2, the pocket 109 is connected to the tip surface 105, the upper surface 107a, and the first side surface 107c.

[0020] As shown in the example in FIGS. 2 and 3 , the pocket 109 may have a bottom surface 115. The bottom surface 115 may be aligned along the first central axis L1 or may be inclined relative to the first central axis L1. For example, the bottom surface 115 may be inclined so as to approach the first central axis L1 as it approaches the rear end 100b. Here, the inclination angle of the bottom surface 115 relative to the first central axis L1 may be, for example, approximately 0° to 20°. The bottom surface 115 may be a surface in the pocket 109 against which the insert 200 abuts. Furthermore, the insert 200 may be fixed in the pocket 109 by sandwiching the insert 200 between the bottom surface 115 and a clamper 300.

[0021] 2 and 3, the first hole 111 may extend from the tip surface 105 toward the rear end 100b. As will be described later, a clamper 300 may be attached to the first hole 111. The first hole 111 may have a certain angle with respect to the first central axis L1 of the holder 100, or may extend parallel to the first central axis L1. When the first hole 111 extends parallel to the first central axis L1 of the holder 100, the insert 200 can be easily replaced.

[0022] The outer diameter of the first hole 111 may be constant or may vary. When the outer diameter of the first hole 111 varies, the outer diameter of the first hole 111 may become smaller as it approaches the rear end 100b.

[0023] The second hole 113 may extend from the side surface 107 to the first hole 111. As shown in an example in Fig. 7 , the second hole 113 may open at a location on the side surface 107 opposite the pocket 109. Specifically, as shown in an example in Fig. 5 , the second hole 113 may extend from the second side surface 107d to the first hole 111. As will be described later, a fixing member 400 can be attached to the second hole 113.

[0024] 5 , the second hole 113 may be inclined with respect to the first hole 111. For example, the second hole 113 may be perpendicular to the first hole 111. Furthermore, as long as the second hole 113 extends from the side surface 107 to the first hole 111, the central axis of the second hole 113 may intersect with the central axis of the first hole 111, or the central axis of the second hole 113 and the central axis of the first hole 111 may be in a twisted relationship.

[0025] <Insert> The insert 200 positioned in the pocket 109 is not limited to a particular shape. As an example shown in Figures 2 and 3, the insert 200 may have a polygonal plate shape. The polygonal plate-shaped insert 200 may have an upper surface 201, a lower surface 203, a pair of lateral surfaces 205, and a through hole 207.

[0026] 2 and 3 , the upper surface 201 may be a surface located at the top of the insert 200. The lower surface 203 may be a surface located at the bottom of the insert 200. The pair of lateral side surfaces 205 may be surfaces located between the upper surface 201 and the lower surface 203. Of the pair of lateral side surfaces 205, a surface that abuts against the bottom surface 115 may be a first lateral side surface 205a, and a surface of the pair of lateral side surfaces 205 that is located opposite the first lateral side surface 205a may be a second lateral side surface 205b. The upper surface 201, the lower surface 203, and the pair of lateral side surfaces 205 may each extend in a direction along the first central axis L1.

[0027] 2 and 3 , the insert 200 may further have a front side surface 209 and a rear side surface 211. The front side surface 209 is a surface of the insert 200 located on the side of the tip 100a of the holder 100, and may protrude forward from the tip 100a of the holder 100 in the cutting tool 1. The rear side surface 211 is a surface of the insert 200 located on the side of the rear end 100b.

[0028] 2 and 3 , the through-hole 207 may open in each of the pair of lateral side surfaces 205. In other words, the through-hole 207 may extend from the first lateral side surface 205 a to the second lateral side surface 205 b. In this case, the through-hole 207 may open in the center portion of each of the pair of lateral side surfaces 205. A clamper 300 is inserted into the through-hole 207.

[0029] The size of the insert 200 is not particularly limited. For example, the length in the direction along the first central axis L1 can be set to approximately 1 mm to 50 mm. The height from the upper surface 201 to the lower surface 203, in other words, the width in the vertical direction, can be set to approximately 1 mm to 50 mm. The width between the pair of lateral surfaces 205 can be set to approximately 0.01 mm to 20 mm.

[0030] Examples of the material of the insert 200 include cemented carbide and cermet. Examples of the composition of the cemented carbide include WC-Co, WC-TiC-Co, and WC-TiC-TaC-Co. Here, WC, TiC, and TaC may be hard particles, and Co may be a binder phase.

[0031] The cermet may also be a sintered composite material in which a ceramic component is combined with a metal. An example of a cermet is a titanium compound primarily composed of titanium carbide (TiC) or titanium nitride (TiN). The material of the insert 200 is not limited to the above composition.

[0032] The surface of the insert 200 may be coated with a film formed by chemical vapor deposition (CVD) or physical vapor deposition (PVD). The film may have a composition of titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), and alumina (Al ２ O ３ ) and the like can be mentioned.

[0033] 1 to 3 and 5, a clamper 300 may be inserted into the first hole 111 provided in the holder 100. The clamper 300 may be capable of restraining the insert 200 and may be used to fix the position of the insert 200 relative to the holder 100. For example, the position of the insert 200 may be fixed by applying a pressing force from the clamper 300 to the insert 200, pressing it against the bottom surface 115 of the pocket 109.

[0034] 5 and 8 to 14, the clamper 300 may have a main body 301 and a protrusion 303. As an example shown in FIGS. 1 to 3 and 5, the main body 301 may be inserted into the first hole 111, and the protrusion 303 may be inserted into the through-hole 207.

[0035] The clamper 300 may be generally L-shaped, with the main body 301 and the protrusion 303 corresponding to two sides of the L. For example, the rod-shaped main body 301 may correspond to the long side of the L, and the rod-shaped protrusion 303 may protrude laterally from near one end of the main body 301, thereby corresponding to the short side of the L.

[0036] 5 , the protrusion 303 may fix the position of the insert 200 while being inserted into the through-hole 207. Specifically, the protrusion 303 may be inserted into the through-hole 207, and a portion of the protrusion 303 may be abutted against the vicinity of the opening of the through-hole 207 on the second lateral side surface 205 b.

[0037] By moving the fixing member 400 in one direction along a second central axis L2 (a direction away from the insert 200 in the example shown in FIG. 5 ), which will be described later, the fixing member 400 can press the main body 301 in a direction toward the rear end 100b. This causes the protrusion 303 to move in a direction toward the rear end 100b, and a force pressing the insert 200 toward the bottom surface 115 of the pocket 109 can be applied from the clamper 300 to the insert 200.

[0038] Furthermore, when the fixing member 400 is moved in the opposite direction (in the direction toward the insert 200 in the example shown in FIG. 5 ), the fixing member 400 can press the main body 301 toward the tip 100 a. This causes the protrusion 303 to move toward the tip 100 a, and the insert 200 can be removed from the pocket 109.

[0039] 8 , the main body portion 301 may have a slit 305. The slit 305 may open toward the rear end 100b and the second hole 113. The slit 305 may open to face the second hole 113 when the main body portion 301 is inserted into the first hole 111. In other words, the second hole 113 and the slit 305 form a space into which the fixing member 400 is inserted. Furthermore, the slit 305 may open toward the rear end 100b when the main body portion 301 is inserted into the first hole 111.

[0040] The main body 301 has the slit 305, which makes it easy to attach the main body 301 to the holder 100. Specifically, even when the fixing member 400 is inserted into the second hole 113, the clamper 300 can be easily inserted into the first hole 111.

[0041] 9 and 10 , the slit 305 is partially located on the rear end 100b side of the main body 301. In other words, as in the example shown in FIGS. 9 and 10 , the main body 301 may have a first portion 307 and a second portion 309. The first portion 307 has the slit 305. The second portion 309 is located closer to the front end 100a of the holder 100 than the first portion 307.

[0042] According to the cutting tool 1 of the above aspect, the fixing member 400 is positioned in the slit 305 provided in the clamper 300. When the fixing member 400 presses a clamper 300 that does not have the slit 305, the fixing member 400 abuts against the end of the clamper 300 on the rear end 100b side. However, with the cutting tool 1 of the above aspect, the fixing member 400 can press the clamper 300 at a location away from the end of the clamper 300. In other words, the location of the clamper 300 that is pressed by the fixing member 400 can be moved closer to the center of the clamper 300, rather than the end of the clamper 300. Therefore, according to the cutting tool 1 of the above aspect, the clamper 300 is less likely to tilt, improving the accuracy of fixing the insert 200.

[0043] If the central axis of the fixing member 400 described later is defined as the second central axis L2, the width W1 of the first portion 307 in the direction along this second central axis L2 and the width W2 of the second portion 309 in the direction along the second central axis L2 may be constant or may be different from each other.

[0044] 5 and 10 , the width W1 of the first portion 307 in the direction along the second central axis L2 may be smaller than the width W2 of the second portion 309 in the direction along the second central axis L2. In the above-described configuration, the clamper 300 can easily move inside the first hole 111, and the insert 200 can easily be fixed by the clamper 300.

[0045] The outer diameter D1 of the first hole 111 at a portion facing the first portion 307 may be smaller than the outer diameter D2 of the first hole 111 at a portion facing the second portion 309. In the above-described configuration, when the fixing member 400 presses the clamper 300, the slit 305 is prevented from opening excessively. Therefore, the main body 301 is less likely to be damaged.

[0046] The outer diameter of the first hole 111 may become smaller as it approaches the rear end 100b. In the above-described configuration, when the fixing member 400 presses the clamper 300, the slit 305 is prevented from being opened excessively. Therefore, the main body 301 is less likely to be damaged.

[0047] 8 to 14, the slit 305 may have a bottom 311 extending in a direction along the second central axis L2. The bottom 311 may be located on the side of the slit 305 that is closer to the tip 100a of the holder 100. Since the slit 305 opens toward the second hole 113, the bottom 311 extends in a direction along the second central axis L2. When viewed from a direction along the second central axis L2 as shown in FIG. 9, the bottom 311 may have an arc-shaped portion.

[0048] As shown in the example in Figures 10 to 14, the bottom portion 311 may have a first end 311a, a second end 311b, and a central portion 311c. The first end 311a may open toward the second hole 113. The second end 311b may open on the opposite side of the first end 311a. As shown in the example in Figures 10 to 14, the central portion 311c may be located between the first end 311a and the second end 311b.

[0049] 10, the first end 311a and the second end 311b may each have a tapered shape in which the inner diameter increases with increasing distance from the central portion 311c. In this configuration, the clamper 300 is likely to come into contact with the fixing member 400, and the fixing member 400 is likely to move the clamper 300. This makes it easy to attach and detach the insert 200 to and from the holder 100.

[0050] 15, the abutment portion 403 may have a tapered shape. Furthermore, the abutment portion 403 may be able to abut against at least one of the first end 311a and the second end 311b. In the above-described configuration, the fixing member 400 is likely to come into contact with the clamper 300, and the fixing member 400 is likely to move the clamper 300. This makes it easy to attach and detach the insert 200.

[0051] As shown in the example in Figures 8 and 11 to 14, the first portion 307 may have a first jaw 313a and a second jaw 313b facing each other. In Figures 10 and 11, the second jaw 313b is indicated by a thick line for ease of visual understanding. The first jaw 313a and the second jaw 313b may be located on the rear end 100b side of the main body 301. The first jaw 313a and the second jaw 313b may also be connected to the bottom 311.

[0052] 8 and 11 to 14, second jaw 313b may have second opposing surface 315b facing first jaw 313a. In other words, the area surrounded by the thick line in Fig. 10 may be second opposing surface 315b. Second opposing surface 315b may have second protrusion 317b protruding toward tip 100a.

[0053] First jaw 313a may have the same configuration as second jaw 313b. That is, first jaw 313a may have first opposing surface 315a facing second jaw 313b. Furthermore, first opposing surface 315a may have first protrusion 317a protruding toward tip 100a. In the case of the above configuration, when clamper 300 is moved by fixing member 400, the movement of clamper 300 is easily controlled.

[0054] Here, second jaw 313b may be a region of first portion 307 where second opposing surface 315b and second opposing surface 315b are overlapped downward. That is, in Fig. 11, the region surrounded by the thick line may be second jaw 313b. Furthermore, first jaw 313a, like second jaw 313b, may be a region of first portion 307 where first opposing surface 315a and first opposing surface 315a are overlapped upward.

[0055] The bottom portion 311 may be the portion of the first portion 307 excluding the first jaw portion 313 a and the second jaw portion 313 b.

[0056] As shown in the examples in Figures 11 and 14, the bottom portion 311 may have a first step portion 319 connecting the first end portion 311a and the central portion 311c. The height H of the first step portion 319 may be constant or may not be constant. Here, the height H of the first step portion 319 refers to the width of the first step portion 319 in the direction from the outer periphery of the bottom portion 311 toward the second central axis L2, as shown in the example in Figure 14. As shown in the example in Figure 14, the height H of the first step portion 319 may increase as it approaches the tip 100a.

[0057] 11 to 14, the inner diameter at the first end 311a may be larger than the inner diameter at the central portion 311c. Furthermore, the bottom portion 311 may have a first step portion 319 connecting the first end 311a and the central portion 311c. The height H of the first step portion 319 may increase toward the tip 100a. With the above configuration, when the clamper 300 is moved by the fixing member 400, the movement of the clamper 300 is easily controlled.

[0058] The clamper 300 is not limited to a particular shape, but may be configured so that it slides easily in the direction of extension of the first central axis L1 of the holder 100 but does not slide easily around the first central axis L1 of the holder 100. For example, the clamper 300 may be shaped like a polygonal pillar or an elliptical pillar. This configuration makes it easy to align the opening of the slit 305 of the clamper 300 with the second hole 113 of the holder 100. This makes it easy to align the clamper 300 with the fixing member 400, making it easier to replace the insert 200.

[0059] The clamper 300 may be made of, for example, steel or cast iron. In particular, when steel is used among these materials, the clamper 300 has high toughness.

[0060] <Fixing Member> The fixing member 400 may be inserted into the second hole 113 and the bottom 311. As an example, the fixing member 400 is inserted into the second hole 113, and the clamper 300 is further inserted into the first hole 111. Here, the clamper 300 is inserted into the first hole 111 so that the fixing member 400 is sandwiched between the first jaw portion 313 a and the second jaw portion 313 b. When the clamper 300 is further pushed in, the fixing member 400 is inserted so as to penetrate the bottom 311. Through the above process, the clamper 300 and the fixing member 400 may be attached to the holder 100.

[0061] 15 , the fixing member 400 may have a pair of threaded portions 401, a pair of abutting portions 403, and a connecting portion 405. In the fixing member 400 of the example shown in FIG. 15 , the pair of threaded portions 401 are located at the ends in the direction along the second central axis L2, and the connecting portion 405 is located in the center in the direction along the second central axis L2. The pair of abutting portions 403 are located so as to be sandwiched between the pair of threaded portions 401 and the connecting portion 405.

[0062] 15 , the pair of threaded portions 401 may extend along the second central axis L2 and have thread grooves on their outer circumferential surfaces. Here, only one of the pair of threaded portions 401 may have thread grooves, or both of the pair of threaded portions 401 may have thread grooves.

[0063] 15 , the abutment portion 403 may have a tapered shape. In the case of a tapered shape, the abutment portion 403 may be able to abut against at least one of the first end 311 a and the second end 311 b. The abutment portion 403 may be connected to the threaded portion 401. The connecting portion 405 may be connected to the abutment portion 403.

[0064] The material of the fixing member 400 may be, for example, steel or cast iron. In particular, when steel is used among these materials, the fixing member 400 has high toughness.

[0065] <Method of Attaching and Removing Insert> As shown in an example in Fig. 16, the clamper 300 can be operated using the fixing member 400. When the fixing member 400 is operated so that the fixing member 400 changes from the state shown in Fig. 16(b) to the state shown in Fig. 16(a), in other words, so that the fixing member 400 approaches the second side surface 107d of the holder 100, the abutment portion 403 of the fixing member 400 and the second end portion 311b of the clamper 300 may abut against each other.

[0066] When the abutting portion 403 and the second end portion 311b abut, their respective tapered portions may slide relative to each other. In the above case, as shown in the example of FIG. 16, the clamper 300 may move toward the rear end 100b, in other words, move so as to be drawn into the first hole 111. By moving in this manner, the clamper 300 applies a force to the insert 200 that presses it against the bottom surface 115, thereby fixing it to the holder 100.

[0067] Conversely, when the fixing member 400 is operated so that it changes from the state shown in Figure 16(c) to the state shown in Figure 16(d), in other words, so that the fixing member 400 moves away from the side surface 107 of the holder 100, the abutment portion 403 of the fixing member 400 and the first end portion 311a of the clamper 300 may abut.

[0068] When the abutting portion 403 and the second end portion 311b abut, their respective tapered portions may slide relative to each other. In the above case, as shown in the example of FIG. 16, the clamper 300 may move toward the rear end 100b. By moving in this manner, the force pressing the insert 200 against the bottom surface 115 is weakened, making it easier to remove the insert 200 from the holder 100.

[0069] The attachment and detachment of the insert 200 by the clamper 300 is not limited to the example shown in Fig. 16. When the fixing member 400 is operated so that the fixing member 400 approaches the second side surface 107d of the holder 100, the clamper 300 may move so as to approach the tip 100a of the holder 100.

[0070] Furthermore, when the fixing member 400 is operated so that the fixing member 400 moves away from the second side surface 107d of the holder 100, the clamper 300 may move closer to the rear end 100b.

[0071] In the example shown in Figure 8, the main body 301 has the above-mentioned slit 305, and the fixing member 400 is partially positioned within this slit 305. With this configuration, the fixing member 400 can press the clamper 300 at a location away from the end face of the clamper 300. This makes it difficult for the clamper 300 to tilt with respect to the first central axis L1, allowing the insert 200 to be accurately fixed. In addition, the slit 305 makes it possible to insert the clamper 300 into the first hole 111 of the holder 100 without removing the fixing member 400 from the holder 100.

[0072] Furthermore, the fixing member 400 is configured to pass through the clamper 300, and it is possible to change whether the fixing member 400 contacts the first end 311 a or the second end 311 b of the clamper 300 simply by changing the direction in which the fixing member 400 is turned. Therefore, the movement of the clamper 300 in the direction along the first central axis L1 can be controlled by the fixing member 400.

[0073] <Method for Manufacturing Machined Product> The machined product 501 can be produced by cutting a workpiece 503. A method for manufacturing a machined product in a non-limiting embodiment of the present disclosure may include the following steps: (1) a step of rotating the workpiece 503; (2) a step of bringing a cutting tool 1, such as that exemplified in the above embodiment, into contact with the rotating workpiece 503; and (3) a step of separating the cutting tool 1 from the workpiece 503.

[0074] More specifically, first, as shown in the example in Fig. 17 , the workpiece 503 is rotated around the axis O, and the cutting tool 1 is brought relatively close to the workpiece 503. Next, as shown in the examples in Figs. 18 and 19 , the ridge line (cutting edge) of the cutting tool 1 is brought into contact with the workpiece 503 to cut the workpiece 503. Then, as shown in the example in Fig. 20 , the cutting tool 1 is moved relatively away from the workpiece 503.

[0075] In Fig. 17, the axis O is fixed and the workpiece 503 is rotated around the axis O while the cutting tool 1 is moved in the Y1 direction to approach the workpiece 503. In Figs. 18 and 19, the cutting edge of the insert 200 is brought into contact with the rotating workpiece 503 to cut the workpiece 503. In Fig. 20, the cutting tool 1 is moved in the Y2 direction while the workpiece 503 is being rotated to move it away.

[0076] In the cutting process in the manufacturing method of the embodiment, the cutting tool 1 is moved in each step to bring the cutting tool 1 into contact with the workpiece 503 or to move the cutting tool 1 away from the workpiece 503, but of course, this is not limited to this form.

[0077] For example, in step (1), the workpiece 503 may be brought closer to the cutting tool 1. Similarly, in step (3), the workpiece 503 may be moved away from the cutting tool 1. To continue the cutting process, the workpiece 503 may be kept rotating, and the step of bringing the cutting edge of the insert 200 into contact with different locations on the workpiece 503 may be repeated.

[0078] Typical examples of materials for the workpiece include carbon steel, alloy steel, stainless steel, cast iron, and non-ferrous metals.

[0079] 1 Cutting tool 100 Holder 100a Tip 100b Rear end 101 Head 103 Shank 105 Tip surface 107 Side 107a Upper surface 107b Lower surface 107c First side 107d Second side 109 Pocket 111 First hole 113 Second hole 115 Bottom surface 200 Insert 201 Upper surface 203 Lower surface 205 Pair of lateral sides 205a First lateral side 205b Second lateral side 207 Through hole 209 Front side 211 Rear side 300 Clamp 301 Main body 303 Projection 305 Slit 307 First portion 309 Second portion 311 Bottom 311a...First end 311b...Second end 311c...Central portion 313a...First jaw portion 313b...Second jaw portion 315a...First opposing surface 315b...Second opposing surface 317a...First convex portion 317b...Second convex portion 319...First step portion 400...Fixing member 401...Threaded portion 403...Abutment portion 405...Connection portion 501...Machine processed product 503...Workpiece D1...Outer diameter of a portion of the first hole facing the first portion D2...Outer diameter of a portion of the first hole facing the second portion H...Height of the first step portion L1...First central axis L2...Second central axis O...Rotation axis of the workpiece W1...Width of the first portion in the direction along the second central axis L2 W2: Width of the second portion in the direction along the second central axis L2

Claims

1. A cutting tool comprising: a holder having a rod shape extending along a first central axis from a front end to a rear end, the holder having a front end face located on the front end side, a side face adjacent to the front end face, a first hole extending from the front end face toward the rear end, a second hole extending from the side face to the first hole, and a pocket having a bottom face located on the front end side; an insert located in the pocket and having a through hole; a clamp inserted into the first hole; and a fixing member having a rod shape extending along a second central axis and inserted into the second hole, wherein the clamp has a main body portion inserted into the first hole and a protrusion portion extending from the main body portion toward the insert and inserted into the through hole of the insert, the main body portion has a slit opening toward the rear end and the second hole, and the fixing member has a threaded portion extending along the second central axis and having a thread groove on an outer peripheral surface, and a contact portion adjacent to the threaded portion, inserted into the slit, and contacting the clamp.

2. The cutting tool according to claim 1, wherein the main body portion has a first portion having the slit and a second portion located on the front end side of the first portion, and a width of the first portion of the main body portion in a direction along the second central axis is smaller than a width of the second portion of the main body portion in a direction along the second central axis.

3. The cutting tool according to claim 2, wherein an outer diameter of a portion of the first hole facing the first portion is smaller than an outer diameter of a portion of the first hole facing the second portion.

4. The cutting tool according to claim 3, wherein an outer diameter of the first hole becomes smaller as it approaches the rear end.

5. The slit is located on the front end side and has a bottom portion extending in a direction along the second central axis, the bottom portion has a first end portion including an end opening toward the second hole, a second end portion including an end opening on the opposite side of the first end portion in the direction along the second central axis, and a central portion located between the first end portion and the second end portion, and the first end portion and the second end portion each have a tapered portion where an inner diameter increases as it moves away from the central portion. The cutting tool according to any one of claims 1 to 4.

6. The cutting tool according to claim 5, wherein the contact portion has a tapered shape and is capable of contacting at least one of the first end portion and the second end portion.

7. The slit has a bottom portion located on the tip side and extending in a direction along the second central axis, and a first jaw portion and a second jaw portion located on the rear end side and connected to the bottom portion. The first jaw portion has a first opposing surface facing the second jaw portion, the second jaw portion has a second opposing surface facing the first jaw portion, the first opposing surface has a first convex portion protruding toward the tip, and the second opposing surface has a second convex portion protruding toward the tip. The cutting tool according to any one of claims 1 to 6.

8. The bottom portion has a first end portion including an end opening toward the second hole, a second end portion including an end opening on the opposite side of the first end portion in the direction along the second central axis, and a central portion located between the first end portion and the second end portion. The inner diameter at the first end portion is larger than the inner diameter at the central portion, the bottom portion further has a first stepped portion connecting the first end portion and the central portion, and the height of the first stepped portion increases as it approaches the tip. The cutting tool according to claim 7.

9. A method for manufacturing a machined product, comprising the steps of rotating a workpiece, bringing the cutting tool according to any one of claims 1 to 8 into contact with the rotating workpiece, and separating the cutting tool from the workpiece.

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