Patent ID: 12220753

EMBODIMENTS

<Rotary Tools>

Rotary tools in non-limiting embodiments of the present disclosure may be described in detail with reference to the drawings. Specifically, a drill may be described in detail with reference to the drawings as a non-limiting embodiment of the rotary tools. Examples of the rotary tools may include, besides the drills, end mills and reamers. Hence, the drill described in the following may be replaced with the rotary tool, such as the end mill.

For the sake of description, the drawings referred to in the following may illustrate, in simplified form, only main members among members constituting the non-limiting embodiments. The rotary tools may therefore be capable of including any arbitrary structural member not illustrated in the drawings referred to in the present specification. Dimensions of the members in each of the drawings may faithfully represent neither dimensions of actual structural members nor dimensional ratios of these members. These points may also be true for a method for manufacturing a machined product described later.

The rotary tool1in a non-limiting embodiment illustrated inFIG.1may be a drill, and may include a base3which has a bar shape extended along a rotation axis X from a first end3atoward a second end3b. The base3having the bar shape may be rotatable in a direction of an arrow Y around the rotation axis X as in the non-limiting embodiment illustrated inFIG.1in a cutting process of a workpiece for the purpose of manufacturing a machined product.

A lower left end of the base3may be the first end3a, and an upper right end may be the second end3bin the non-limiting embodiment illustrated inFIG.1. An upper end part of the base3may be the first end3a, and a lower end part thereof may be the second end3bin non-limiting embodiments illustrated inFIGS.2to6. In general, the first end3amay also be called a front end, and the second end3bmay also be called a rear end.

FIGS.3to6may illustrate a state where the rotary tool illustrated inFIG.2is rotated by a predetermined angle in a rotation direction. Specifically,FIG.3may illustrate a state where the rotary tool illustrated inFIG.2is rotated by 10 degrees in the rotation direction.FIG.4may illustrate a state where the rotary tool illustrated inFIG.2is rotated by 70 degrees in the rotation direction.FIG.5may illustrate a state where the rotary tool illustrated inFIG.2is rotated by 90 degrees in the rotation direction.FIG.6may illustrate a state where the rotary tool illustrated inFIG.2is rotated by 180 degrees in the rotation direction.

The base3in the non-limiting embodiment illustrated inFIG.1may have a columnar shape. The term “columnar shape” may be a concept including not only a strict circular column but also those having a slight concave-convex or curved surface. The shape of the base3is not be limited to the columnar shape.

An outer diameter D in the base3may be settable to, for example, 4-25 mm. A relationship between L and D may be settable to, for example, L=4D to 15D, in which L is a length of the base3in a direction along the rotation axis X.

The base3may include a cutting part5located so as to include the first end3a, and a shank part7located on a side closer to the second end3bthan the cutting part5in the non-limiting embodiment illustrated inFIGS.1to6. The cutting part5may include a portion brought into contact with a workpiece. The portion may perform a major role in a cutting process of the workpiece. The shank part7may be a part which is held by, for example, a spindle to be rotated in a machine tool, and which is designed according to a shape of the spindle. Examples of the shape of the shank part7may include straight shank, long shank, long neck and tapered shank.

The cutting part5may include an outer peripheral surface11, a first cutting edge13, a first flute15and a first ridgeline17in the non-limiting embodiment illustrated inFIG.1.

The outer peripheral surface11may be a surface located on an outer periphery of the cutting part5.FIGS.1to6may illustrate non-limiting embodiments in which a distance from the rotation axis X to the outer peripheral surface11is approximately kept constant.

The first cutting edge13may be located from the first end3atoward the outer peripheral surface11in the non-limiting embodiment illustrated inFIG.1. The first cutting edge13may generally also be called a tip edge. The first cutting edge13may perform a major role in chip generation during the cutting process. These points may also be true for a second cutting edge37described later.

The first flute15may be spirally extended from the first cutting edge13toward a side of the second end3bin the non-limiting embodiment illustrated inFIG.1. The first flute15may be a flute for discharging the chips generated by the first cutting edge13during cutting of the workpiece. The first flute15may therefore also be called a chip discharge flute. These points may also be true for a second flute39described later.

In the non-limiting embodiment illustrated inFIG.1, the first flute15may be spirally extended around the rotation axis X so as to extend to a side opposite to the rotation direction Y as going from the first cutting edge13toward the second end3b. The term “spirally extending” may denote that the first flute15extends approximately twistingly as going from the first cutting edge13toward the side of the second end3b. Therefore, the first flute15may include a partially untwisted part. These points may also be true for the second flute39described later.

In the non-limiting embodiment illustrated inFIG.1, the first ridgeline17may be a ridgeline formed by the first flute15and the outer peripheral surface11adjacent to the first flute15on a rear side in the rotation direction Y of the rotation axis X.

The base3may further include a flow path9which is located inside the base3and is extended along the rotation axis X in the non-limiting embodiment illustrated inFIG.1. The flow path9may be a part that permits passage of fluid therethrough.

The fluid passing through the flow path9may generally be called a coolant. Examples of the coolant may include water-insoluble cutting fluids, water-soluble cutting fluids and compressed air. Examples of the water-insoluble cutting fluids may include cutting fluids represented by oil-based cutting fluids, inert extreme pressure-based cutting fluids and active extreme pressure-based cutting fluids. Examples of the water-soluble cutting fluids may include emulsion-type, soluble-type and solution-type cutting fluids. The coolant may be used by suitably selecting according to a material of the workpiece.

Examples of shape of the flow path9may include straight line shape and curvilinear shape. Examples of the curvilinear shapes may include spiral shapes. The shape of the flow path9is not particularly limited as long as it permits passage of the fluid. This may also be true for a sectional shape of the flow path9. A cross-section of the flow path9orthogonal to a flow direction of the fluid may have, for example, a circular shape, an elliptical shape or a polygonal shape.

The flow path9may include a main flow path19and a first sub flow path21in the non-limiting embodiment illustrated inFIG.1.

The main flow path19may be extended from a side of the second end3btoward a side of the first end3ain the non-limiting embodiment illustrated inFIG.1. The main flow path19may have a spiral shape in the non-limiting embodiment illustrated inFIG.1. In other words, the main flow path19may be spirally extended from the side of the second end3btoward the side of the first end3ain the non-limiting embodiment illustrated inFIG.1. The shape of the main flow path19is not limited to the spiral shape. For example, the main flow path19may have a straight line shape. An inner diameter of the main flow path19may be settable to, for example, 0.5-3 mm.

One or a plurality of the main flow paths19may be included. In the case of the plurality of the main flow paths19, these main flow paths19may have the same or different configurations. The two main flow paths9may be included as in the non-limiting embodiment illustrated inFIG.1. In other words, the flow path9may include a first main flow path19aand a second main flow path19bas in the non-limiting embodiment illustrated inFIG.1. The first main flow path19aand the second main flow path19bmay have the same configuration as in the non-limiting embodiment illustrated inFIG.1.

The main flow path19may include an inflow port19cand an outflow port19din the non-limiting embodiment illustrated inFIG.1.

The inflow port19cmay be a part that permits inflow of an outwardly supplied fluid into the main flow path19. The inflow port19cmay be located on an end surface at the second end3bin the non-limiting embodiment illustrated inFIG.1. A position of the inflow port19cis not limited to the end surface at the second end3b. For example, the inflow port19cmay be located on an outer peripheral surface of the shank part7. One or a plurality of the inflow ports19cmay be included.

The outflow port19dmay be a part that permits discharge of the fluid. The outflow port19dmay be located at an end surface on the side of the first end3aso that the fluid can be ejected toward a direction away from the base3in the non-limiting embodiment illustrated inFIG.1. A position of the outflow port19dis not limited to the end surface on the side of the first end3a. One or a plurality of the outflow ports19dmay be included.

The main flow path19may not include the outflow port19d. Specifically, a first sub flow path21described later may be extended from the main flow path19, and the fluid may be discharged from a first opening23of the first sub flow path21as in the non-limiting embodiment illustrated inFIG.2. In this case, for example, the main flow path19may not include the outflow port19d.

The first sub flow path21may be extended from the main flow path19toward a side of the second end3bin the non-limiting embodiment illustrated inFIG.2. The first sub flow path21may include a first opening23that opens into the first flute15. The first sub flow path21may be a part which connects to the main flow path19and permits discharge of the fluid from the first opening23toward the side of the second end3b. The first opening23may correspond to an edge of the first sub flow path21which opens into the first flute15. These points may also be true for a second sub flow path31and a third sub flow path41described later.

The first sub flow path21may have a straight line shape and may be extended from the first main flow path19atoward the side of the second end3b. Alternatively, the first sub flow path21may be extended from the second main flow path19btoward the side of the second end3b.

A first angle θ1formed by the rotation axis X and the first sub flow path21may be smaller than a helix angle θ2formed by the rotation axis X and the first ridgeline17in a non-limiting embodiment illustrated inFIGS.8,9and11. With this configuration, even if the helix angle θ2is increased to increase the amount of cutting, the fluid discharged from the first opening23toward the side of the second end3bmay tend to flow in a direction approaching the rotation axis X. Hence, chips generated by the first cutting edge13during the cutting process may tend to flow toward the side of the second end3bby the fluid ejected from the first opening23. The rotary tool1may therefore have excellent discharge performance. The rotary tool1may also have good cutting performance because the helix angle θ2can be increased to increase the amount of cutting.

As to the first angle θ1and the helix angle θ2, θ1and θ2, each being a value of the angle, may be indicated by an absolute value. Specifically, a magnitude relationship between the first angle θ1and the helix angle θ2may be indicated by |θ2|>|θ1|.

The first angle θ1may be evaluated in a state where an angle formed by the rotation axis X and a central axis Q1of the first sub flow path21becomes maximum if the cutting part5is viewed from a direction orthogonal to the rotation axis X, as in the non-limiting embodiment illustrated inFIG.8. The central axis Q1of the first sub flow path21may be obtainable by a continuous existence of the center of the first inner diameter of the first sub flow path21. The first angle θ1may be settable to, for example, −20 to 25 degrees.

The helix angle θ2may be evaluated by an angle formed by the rotation axis X and the first ridgeline17if the cutting part5is viewed from the direction orthogonal to the rotation axis X, as in the non-limiting embodiment illustrated inFIGS.9and11. Alternatively, the helix angle θ2may be evaluated using, instead of the rotation axis X, an imaginary straight line which passes through one point on the first ridgeline17and is parallel to the rotation axis X. The helix angle θ2may be settable to, for example, −5 degrees to 40 degrees.

The first opening23may be located closer to the first end3athan a center5aof the cutting part5in a direction along the rotation axis X as in the non-limiting embodiment illustrated inFIG.2. If satisfying the above configuration, the first opening23may be located in the vicinity of the first cutting edge13, so that the chips generated by the first cutting edge13during the cutting process may tend to flow to the side of the second end3bby the fluid ejected from the first opening23, thus leading to enhanced chip discharge performance.

The first ridgeline17may include a first portion25and a second portion27located closer to the side of the second end3bthan the first portion25as in the non-limiting embodiment illustrated inFIGS.3and5. A first helix angle θ2aformed by the rotation axis X and the first portion25may be different from a second helix angle θ2bformed by the rotation axis X and the second portion27as in the non-limiting embodiment illustrated inFIGS.9and11. If satisfying these configurations, it may be possible to achieve both an increased amount of cutting and enhanced strength of the rotary tool1. Specifically, the amount of cutting can be increased if the helix angle is large. The strength of the rotary tool1can be enhanced if the helix angle is small. If the first helix angle θ2ais different from the second helix angle θ2b, the first angle θ1may be smaller than each of the first helix angle θ2aand the second helix angle θ2b.

The first helix angle θ2amay be larger than the second helix angle θ2bas in the non-limiting embodiment illustrated inFIGS.9and11. If satisfying this configuration, it is may be possible to facilitate the flow of chips in the vicinity of the first cutting edge13to the side of the second end3b.

Although the first helix angle θ2amay be larger than the second helix angle θ2b, it is not intended to limit thereto. For example, the first helix angle θ2amay be smaller than or equal to the second helix angle θ2b.

The first opening23may be located in the vicinity of a boundary29between the first portion25and the second portion27in the non-limiting embodiment illustrated inFIG.5. If satisfying this configuration, chip clogging may be less likely to occur at the boundary29where a chip flow may change. As used herein, the phrase that “the first opening23is located in the vicinity of the boundary29” may be a concept including not only a state where the first opening23is strictly located on the boundary29, but also a state where the first opening23is located in surroundings of the boundary29as long as the above effect is obtainable. For example, the first opening23may be located at a position shifted slightly from the boundary29to the side of the first end3ain the first flute15.

The flow path9may further include other sub flow path in addition to the first sub flow path21. One or a plurality of other sub flow paths may be included. For example, the flow path9may further include a second sub flow path31which is located closer to the side of the second end3bthan the first sub flow path21, and which is extended from the main flow path19to the side of the second end3bas in the non-limiting embodiment illustrated inFIG.1. The second sub flow path31may include a second opening33that opens into the first flute15in the non-limiting embodiment illustrated inFIG.4. If satisfying these configurations, enhanced chip discharge performance may be attainable because the fluid can be discharged from the second opening33of the second sub flow path31in addition to the first opening23of the first sub flow path21toward the side of the second end3b.

The second sub flow path31may have a straight line shape and may be extended from the first main flow path19atoward the side of the second end3bin the non-limiting embodiment illustrated inFIG.4. The second sub flow path31may be extended from the second main flow path19btoward the side of the second end3b.

A second angle θ3formed by the rotation axis X and the second flow path31may be different from the first angle θ1as in a non-limiting embodiment illustrated inFIG.10. If satisfying this configuration, it may be easy to individually control the fluid in the first sub flow path21and the second sub flow path31. The rotary tool1may therefore have good chip discharge performance.

Specifically, a route of the first sub flow path21may tend to become shorter with increasing the first angle θ1. A route of the second sub flow path31may tend to become smaller with increasing the second angle θ3. A path loss may become shorter with decreasing the route of the first sub flow path21or the second sub flow path31. Accordingly, a large amount of the fluid may flow out from the first sub flow path21or the second sub flow path31. This may lead to a large force to push out the chips by the fluid flowing out from the first sub flow path21or the second sub flow path31.

Meanwhile, the fluid flowing out from the first sub flow path21may tend to flow toward the second end3bwith decreasing the first angle θ1. The fluid flowing out from the second sub flow path31may tend to flow toward the second end3bwith decreasing the second angle θ3. Consequently, the chips washed away by the fluid may tend to be stably discharged toward the second end3b.

A fluid control suitable for each of the first sub flow path21and the second sub flow path31can be carried out by suitably adjusting magnitude of the first angle θ1and the second angle θ3. The second angle θ3may be smaller than the helix angle θ2as in the non-limiting embodiment illustrated inFIG.10.

The second angle θ3may be larger than the first angle θ1as in the non-limiting embodiment illustrated inFIGS.8and10. If satisfying this configuration, a chip discharge direction can be stabilized by the fluid flowing out from the first sub flow path21located closer to the side of the first end3athan the second sub flow path31. Additionally, a chip discharge speed can be increased by the fluid flowing out from the second sub flow path31located closer to the side of the second end3bthan the first sub flow path21.

A relationship between the first angle θ1and the second angle θ3is not limited to a relationship that the second angle θ3is larger than the first angle θ1. For example, the second angle θ3may be smaller than the first angle θ1as in a rotary tool1ain a non-limiting embodiment illustrated inFIG.13. If satisfying this configuration, a chip discharge speed can be increased by the fluid flowing out from the first sub flow path21located closer to the side of the first end3athan the second sub flow path31. Additionally, the chips may tend to be stably discharged toward the second end3bby the fluid flowing out from the second sub flow path31located closer to the side of the second end3bthan the first sub flow path21.FIG.13may be a diagram corresponding to the enlarged view illustrated inFIG.10.

The second angle θ3may be evaluated in the same manner as in the first angle θ1. That is, the second angle θ3may be evaluated in a state where an angle formed by the rotation axis X and a central axis Q2of the second sub flow path31may become maximum if the cutting part5is viewed from the direction orthogonal to the rotation axis X, as in the non-limiting embodiment illustrated inFIG.10. The second angle θ3may be settable to, for example, −20 to 25 degrees.

A relationship between the first angle θ1and the second angle θ3is not limited to a relationship that the second angle θ3is larger or smaller than the first angle θ1. For example, the second angle θ3may be equal to the first angle θ1.

A first inner diameter of the first sub flow path21may be different from a second inner diameter of the second sub flow path31as in the non-limiting embodiment illustrated inFIGS.8and10. If satisfying this configuration, it may be possible to adjust an injection pressure of the fluid ejected from the first opening23and the second opening33.

The second inner diameter may be larger than the first inner diameter as in the non-limiting embodiment illustrated inFIGS.8and10. If satisfying this configuration, a volume of the fluid ejected from the second inner diameter can be increased to enhance chip discharge performance in the vicinity of the second inner diameter.

That is, it may be possible to rephrase that the first inner diameter is smaller than the second inner diameter. If satisfying this configuration, a speed of the fluid ejected from the first inner diameter can be increased.

The first inner diameter may be settable to, for example, 0.3-0.9 mm. The second inner diameter may be settable to, for example, 0.3-1.5 mm. A relationship between the first inner diameter and the second inner diameter is not limited to a relationship that the second inner diameter is larger than the first inner diameter. For example, the second inner diameter may be smaller than or equal to the first inner diameter.

The cutting part5may further include a second ridgeline35as in a non-limiting embodiment illustrated inFIG.7. The second ridgeline35may be a ridgeline formed by the first flute15and the outer peripheral surface11adjacent to the first flute15on a front side in the rotation direction Y in the non-limiting embodiment illustrated inFIG.7. The first opening23may be located closer to the first ridgeline17than the second ridgeline35as in the non-limiting embodiment illustrated inFIG.8. If satisfying these configurations, the fluid ejected from the first opening23may be ejected along the first ridgeline17in the first flute15, so that chips generated from the first ridgeline17can be discharged suitably.

The cutting part5may further include other cutting edge in addition to the first cutting edge13. The cutting part5may also include other flute in addition to the first flute15. One or more other cutting edges and other flutes may be included. For example, the cutting part5may further include a second cutting edge37and a second flute39as in the non-limiting embodiment illustrated inFIG.7. The second cutting edge37may be located from the first end3atoward the outer peripheral surface11, and the second flute39may be spirally extended from the second cutting edge37toward the second end3bin the non-limiting embodiment illustrated inFIG.7.

A configuration of the second cutting edge37may be identical with or different from a configuration of the first cutting edge13. Similarly, a configuration of the second flute39may be identical with or different from a configuration of the first flute15. The configuration of the second cutting edge37may be identical with the configuration of the first cutting edge13, and the configuration of the second flute39is identical with the configuration of the first flute15in the non-limiting embodiment illustrated inFIG.7. The second cutting edge37may be located so as to have 180-degree rotational symmetry with respect to the first cutting edge13on the basis of the rotation axis X1in a front view from the side of the first end3a.

The flow path9may further include a third sub flow path41as in the non-limiting embodiment illustrated inFIG.1. The third sub flow path41may be extended from the main flow path19toward the side of the second end3bin the non-limiting embodiment illustrated inFIG.6. The third sub flow path41may include a third opening43that opens into the second flute39. If satisfying these configurations, the fluid can be discharged toward the side of the second end3bfrom the third opening43of the third sub flow path41in addition to the first opening23of the first sub flow path21, thus leading to enhanced chip discharge performance.

The third sub flow path41may have a straight line shape and may be extended from the second main flow path19btoward the side of the second end3bas in the non-limiting embodiment illustrated inFIG.6. Alternatively, the third sub flow path41may be extended from the first main flow path19atoward the side of the second end3b.

The first opening23and the third opening43may be located at different positions in the direction along the rotation axis X as in the non-limiting embodiment illustrated inFIG.6. If satisfying this configuration, stress applied to the first sub flow path21and the third sub flow path41and stress applied to the first opening23and the third opening43may tend to be dispersed in the direction along the rotation axis X. It may therefore be possible to reduce deterioration of the strength of the rotary tool1, so that the rotary tool1may be less likely to be fractured.

The relationship between the first opening23and the third opening43in the direction along the rotation axis X is not limited to the relationship that these two openings are located at the different positions. For example, the first opening23and the third opening43may be located at the same position in the direction along the rotation axis X.

In a non-limiting embodiment illustrated inFIG.12, a third angle θ4formed by the rotation axis X and the third sub flow path41may be evaluated in the same manner as in the first angle θ1. That is, the third angle θ4may be evaluated in a state where an angle formed by the rotation axis X and a central axis Q3of the third sub flow path41may become maximum if the cutting part5is viewed from the direction orthogonal to the rotation axis X, as in the non-limiting embodiment illustrated inFIG.12. The third angle θ4may be settable to, for example, −20 to 25 degrees.

The third angle θ4may be smaller than the helix angle of the second flute39as in the non-limiting embodiment illustrated inFIG.12. Specifically, in the non-limiting embodiment illustrated inFIG.12, the third angle θ4may be smaller than a helix angle formed by the rotation axis X and a third ridgeline in which the third ridgeline is a ridgeline formed by the second flute39and the outer peripheral surface11adjacent to the second flute39on a rear side in the rotation direction Y of the rotation axis X. The third ridgeline may correspond to the first ridgeline17in the non-limiting embodiment illustrated inFIG.12.

As in the non-limiting embodiment illustrated inFIG.12, if the third opening43is located closer to the side of the first end3athan the first opening23in the direction along the rotation axis X, in other words, if the third opening43, the first opening23and the second opening33may be located in this order from the side of the first end3atoward a side of the second end3bin the direction along the rotation axis X, the first angle θ1, the second angle θ3and the third angle θ4may have a relationship that the second angle θ3>the first angle θ1>the third angle θ4.

As in a rotary tool1bin a non-limiting embodiment illustrated inFIG.14, if the first opening23is located closer to the first end3athan the third opening43in the direction along the rotation axis X, in other words, if the first opening23, the third opening43and the second opening33are located in this order from the side of the first end3atoward the side of the second end3bin the direction along the rotation axis X, the first angle θ1, the second angle θ3and the third angle θ4may have a relationship that the second angle θ3>the third angle θ4>the first angle θ1.FIG.14may be a diagram corresponding to the side view illustrated inFIG.6.

The second angle θ3may be smaller than the first angle θ1as described above. In this case, the first angle θ1, the second angle θ3and the third angle θ4may have the following relationship. That is, if the third opening43, the first opening23and the second opening33are located in this order from the side of the first end3atoward the side of the second end3bin the direction along the rotation axis X, the first angle θ1, the second angle θ3and the third angle θ4may have a relationship that the third angle θ4>the first angle θ1>the second angle θ3. Still alternatively, if the first opening23, the third opening43and the second opening33are located in this order from the side of the first end3atoward the side of the second end3bin the direction along the rotation axis X, the first angle θ1, the second angle θ3and the third angle θ4may have a relationship that the first angle θ1>the third angle θ4>the second angle θ3.

A first inner diameter of the first sub flow path21may be smaller than an inner diameter of the main flow path19as in the non-limiting embodiment illustrated inFIG.7. If satisfying this configuration, a fluid pressure of the fluid ejected from the first opening23may tend to become higher. For the same reason, a second inner diameter of the second sub flow path31may be smaller than the inner diameter of the main flow path19, and a third inner diameter of the third sub flow path41may be smaller than the inner diameter of the main flow path19as in the non-limiting embodiment illustrated inFIG.7. The third inner diameter of the third sub flow path41may be settable to, for example, 0.3-2 mm.

For example, cemented carbide and cermet may be usable as a material of the base3. Examples of composition of the cemented carbide may include WC—Co, WC—TiC—Co and WC—TiC—TaC—Co, in which WC, TiC and TaC may be hard particles, and Co may be a binding phase. The cermet may be a sintered composite material obtainable by compositing metal into a ceramic component. Examples of the cermet may include titanium compounds composed mainly of titanium carbide (TiC) or titanium nitride (TiN).

A surface of the base3may be coated with a coating film by using chemical vapor deposition (CVD) method or physical vapor deposition (PVD) method. Examples of composition of the coating film may include titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN) and alumina (Al2O3).

<Method for Manufacturing Machined Product>

A method for manufacturing a machined product in a non-limiting embodiment of the present disclosure may be described in detail below with reference toFIGS.15to17by exemplifying the case of using the above rotary tool1.

The method for manufacturing the machined product in the non-limiting embodiment may include the following steps:(1) rotating the rotary tool1around the rotation axis X;(2) bringing the first cutting edge13in the rotary tool1being rotated into contact with a workpiece100; and(3) moving the rotary tool1away from the workpiece100.

More specifically, firstly, as in the non-limiting embodiment illustrated inFIG.15, the rotary tool1may be relatively brought near the workpiece100by moving the rotary tool1in a direction Z1along the rotation axis X while rotating the rotary tool1around the rotation axis X.

Subsequently, as in the non-limiting embodiment illustrated inFIG.16, the workpiece100may be cut out by bringing the first cutting edge13of the rotary tool1into contact with the workpiece100. In this case, the workpiece100may be cut out while allowing a fluid to flow out from the first opening23.

Thereafter, as in the non-limiting embodiment illustrated inFIG.17, the machined product may be obtained by moving the rotary tool1in a direction Z2so that the rotary tool1may relatively be moved away from the workpiece100.

With the method for manufacturing the machined product in the non-limiting embodiment, the machined product having highly precise machined surface may be obtainable using the rotary tool1having excellent chip discharge performance.

In the non-limiting embodiment illustrated inFIG.15, the rotary tool1may be brought near the workpiece100in a state where the workpiece100is fixed and the rotary tool1is rotated around the rotation axis X. In the non-limiting embodiment illustrated inFIG.16, the workpiece100may be cut out by bringing the first cutting edge13of the rotary tool1being rotated into contact with the workpiece100. The rotary tool1being rotated may be moved away from the workpiece100as in the non-limiting embodiment illustrated inFIG.17.

Although the machined product is obtained by moving the rotary tool1in the non-limiting embodiment illustrated inFIGS.15to17, it is not intended to limit thereto. For example, the workpiece100may be brought near the rotary tool1in the step (1). Similarly, the workpiece100may be moved away from the rotary tool1in the step (3). If it is desired to continue the cutting process, the step of bringing the cutting edge13of the rotary tool1into contact with different portions of the workpiece100may be repeated while keeping the rotary tool1rotated.

Examples of material of the workpiece100may include aluminum, carbon steel, alloy steel, stainless steel, cast iron and nonferrous metals.

While the rotary tools1and the methods for manufacturing a machined product in the non-limiting embodiments of the present disclosure have been exemplified above, the present disclosure is not limited to the above embodiments. It may be, of course, possible to make any arbitrary ones in so far as they do not depart from the gist of the present disclosure.