Rotary Cutting Tools
Patent Information
- Application Number
- JP2024550806
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2024-01-24
- Publication Date
- 2025-12-23
- Estimated Expiration
- 2044-01-24
AI Technical Summary
Existing rotary cutting tools face challenges in effectively supplying coolant from within the main body, particularly for large diameters, leading to inefficiencies and potential tool damage during coolant hole formation.
A rotary cutting tool design featuring a main body with a coolant reservoir groove and a cover with a recess that directs coolant to the groove, along with specific geometric relationships between diameters and distances to ensure effective coolant supply and minimize leakage, even at high pressures.
The design enables efficient coolant supply to cutting inserts, reducing tool breakage during coolant hole formation and extending the life of cutting inserts by minimizing coolant leakage.
Smart Images
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Abstract
Description
[Technical field]
[0001] The present disclosure relates to rotary cutting tools. [Background technology]
[0002] JP 2021-94680 A (Patent Document 1) discloses a mounting member for a slotting cutter with a coolant hole. JP 2010-516483 A (Patent Document 2) discloses a milling cutter assembly in which coolant is supplied to the milling cutter from a coolant supply source. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Patent Publication No. 2021-94680 [Patent Document 2] Special Publication No. 2010-516483 Summary of the Invention [Problem to be solved by the invention]
[0004] An object of the present disclosure is to provide a large diameter rotary cutting tool that can be supplied with coolant from within the body portion. [Means for solving the problem]
[0005] The rotary cutting tool according to the present disclosure is rotatable around a rotation axis and includes a main body and a cover attached to the main body. The main body includes a fitting portion into which coolant is introduced and which is attached to a holder, a coolant reservoir groove located radially outward of the fitting portion, a first mounting hole into which a bolt for fixing the main body to the holder is inserted, and a coolant hole that is connected to the coolant reservoir groove and discharges the coolant. The cover includes a recess for sending the coolant to the coolant reservoir groove. If the maximum diameter of the main body is D1, the outer diameter of the coolant reservoir groove is D2, and the distance between the rotation axis and the center of the first mounting hole in the radial direction is R, and D1, D2, and R are expressed in mm, D1 satisfies Formula 1, D1 and D2 satisfy Formula 2, and R and D2 satisfy Formula 3.
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[0009] According to the present disclosure, it is possible to provide a large diameter rotary cutting tool to which coolant can be supplied from inside the main body. [Brief description of the drawings]
[0010] [Figure 1] FIG. 1 is a first perspective schematic view showing the configuration of a rotary cutting tool according to this embodiment. [Diagram 2] FIG. 2 is an exploded perspective view showing the configuration of the rotary cutting tool according to this embodiment. [Diagram 3]FIG. 3 is a second perspective schematic view showing the configuration of the rotary cutting tool according to this embodiment. [Figure 4] FIG. 4 is a schematic plan view showing the configuration of the main body. [Diagram 5] FIG. 5 is a schematic plan view showing the configuration of the cover. [Figure 6] FIG. 6 is a schematic plan view perspective view showing a state in which the cover is attached to the main body. [Figure 7] FIG. 7 is a first schematic cross-sectional view showing a state in which a holder is attached to a rotary cutting tool. [Figure 8] FIG. 8 is a second schematic cross-sectional view showing a state in which the holder is attached to the rotary cutting tool. [Figure 9] FIG. 9 is a schematic perspective view showing a state in which a workpiece is being machined using a rotary cutting tool. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] [Description of the embodiments of the present disclosure] First, embodiments of the present disclosure (also referred to as the present embodiment) will be listed and described.
[0012] (1) The rotary cutting tool according to the present disclosure is rotatable around a rotation axis and includes a main body and a cover attached to the main body. The main body includes a fitting portion into which coolant is introduced and which is attached to a holder, a coolant reservoir groove located radially outward of the fitting portion, a first mounting hole into which a bolt for fixing the main body to the holder is inserted, and a coolant hole that is connected to the coolant reservoir groove and discharges the coolant. The cover includes a recess for sending the coolant to the coolant reservoir groove. If the maximum diameter of the main body is D1, the outer diameter of the coolant reservoir groove is D2, and the distance between the rotation axis and the center of the first mounting hole in the radial direction is R, and D1, D2, and R are in mm, D1 satisfies Formula 1, D1 and D2 satisfies Formula 2, and R and D2 satisfies Formula 3. This makes it possible to provide a large-diameter rotary cutting tool that can supply coolant from inside the main body.
[0013] (2) In the rotary cutting tool according to (1) above, the inner diameter of the coolant hole is D3, the length of the coolant hole as viewed along the rotation axis is L, and D3 and L are in mm, D3 may satisfy Formula 4, and D3 and L may satisfy Formula 5. This can reduce breakage of the long drill when forming a coolant hole in the rotary cutting tool using the long drill.
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[0016] (3) In the rotary cutting tool according to (1) or (2) above, the recess may be cross-shaped when viewed along the rotation axis. This allows the coolant to be evenly directed toward the coolant reservoir groove. The recess may be formed in the cover so as not to overlap with the first mounting hole into which the bolt is inserted.
[0017] (4) According to the rotary cutting tool according to any one of (1) to (3) above, the cover may be provided with a second mounting hole into which a screw for fixing the cover to the main body is inserted. In the radial direction, the second mounting hole may be located inside the coolant reservoir groove. This can reduce leakage of coolant from the gap between the main body and the cover even when the coolant pressure is high. Therefore, coolant can be effectively supplied to the cutting insert during cutting. As a result, the life of the cutting insert can be extended.
[0018] (5) According to the rotary cutting tool according to any one of (1) to (4) above, the cover may be provided with a third mounting hole into which a screw for fixing the cover to the main body is inserted. The third mounting hole may be located radially outward of the coolant reservoir groove. This can reduce leakage of coolant from the gap between the main body and the cover even when the coolant pressure is high. Therefore, coolant can be effectively supplied to the cutting insert during cutting. As a result, the life of the cutting insert can be extended.
[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific example of a rotary cutting tool according to an embodiment of the present disclosure will be described below with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and the description thereof will not be repeated.
[0020] Fig. 1 is a first perspective schematic view showing the configuration of a rotary cutting tool 100 according to this embodiment. Fig. 2 is an exploded perspective schematic view showing the configuration of the rotary cutting tool 100 according to this embodiment.
[0021] As shown in FIG. 1 and FIG. 2, the rotary cutting tool 100 according to this embodiment is a side cutter that can rotate around a rotation axis A. The rotary cutting tool 100 mainly includes a main body 1, a cover 2, a bolt 41, a cover locking screw 44, a cutting insert 4, and an insert fastening portion 3. The main body 1 has a first side surface 31, a second side surface 32, and an outer peripheral surface 33. The second side surface 32 is located on the opposite side of the first side surface 31. The outer peripheral surface 33 is continuous with each of the first side surface 31 and the second side surface 32. The outer peripheral surface 33 surrounds the rotation axis A. The cutting insert 4 is disposed on the outer peripheral surface 33.
[0022] As shown in Fig. 2, the main body 1 is provided with a fitting portion 16, a first mounting hole 11, a fifth mounting hole 12, and a sixth mounting hole 13. The fitting portion 16 is a portion that is attached to a holder 7, which will be described later. The fitting portion 16 is, for example, a spigot portion. The fitting portion 16 extends along the rotation axis A. The fitting portion 16 is a through hole. The fitting portion 16 opens to each of a first side surface 31 and a second side surface 32.
[0023] A cover arrangement groove 17 is provided on the first side surface 31. The cover arrangement groove 17 is composed of a bottom surface 17a and an inner peripheral surface 17b. The inner peripheral surface 17b is continuous with the bottom surface 17a. The fitting portion 16, the first mounting hole 11, the fifth mounting hole 12, and the sixth mounting hole 13 each open to the bottom surface 17a. The first mounting hole 11 is a through hole. The first mounting hole 11 opens to the second side surface 32. The fifth mounting hole 12 and the sixth mounting hole 13 each are holes with bottoms.
[0024] The cover 2 is attached to the main body 1. The cover 2 is placed in the cover placement groove 17. The cover 2 is provided with a second attachment hole 22, a third attachment hole 23, and a fourth attachment hole 21. Each of the second attachment hole 22, the third attachment hole 23, and the fourth attachment hole 21 is a through hole.
[0025] The first mounting hole 11 is positioned in the fourth mounting hole 21. The bolt 41 passes through each of the first mounting hole 11 and the fourth mounting hole 21. The cover locking screw 44 has an inner mounting screw 42 and an outer mounting screw 43. The second mounting hole 22 is positioned in the fifth mounting hole 12. The inner mounting screw 42 passes through the second mounting hole 22 and reaches the fifth mounting hole 12. The inner mounting screw 42 is fastened to the main body 1 at the fifth mounting hole 12.
[0026] The third mounting hole 23 is positioned in the sixth mounting hole 13. The outer mounting screw 43 passes through the third mounting hole 23 and reaches the sixth mounting hole 13. The outer mounting screw 43 is fastened to the main body 1 at the sixth mounting hole 13. Each of the inner mounting screw 42 and the outer mounting screw 43 fixes the cover 2 to the main body 1.
[0027] Fig. 3 is a second perspective schematic diagram showing the configuration of the rotary cutting tool 100 according to this embodiment. As shown in Fig. 3, a protrusion 5 is provided on the second side surface 32 of the main body 1. The first mounting hole 11 opens into the protrusion 5. The protrusion 5 is provided with a groove 8 extending in the radial direction. The radial direction is the direction extending radially from the rotation axis A. The fitting portion 16 opens into the protrusion 5. The groove 8 is continuous with the fitting portion 16.
[0028] FIG. 4 is a schematic plan view showing the configuration of the main body 1. As shown in FIG. 4, the main body 1 is provided with a coolant reservoir groove 15. The coolant reservoir groove 15 is provided on the bottom surface 17a. The coolant reservoir groove 15 is located radially outward of the fitting portion 16. When viewed along the rotation axis A, the coolant reservoir groove 15 is, for example, annular. The coolant reservoir groove 15 surrounds the rotation axis A. The coolant reservoir groove 15 is not limited to being annular. The coolant reservoir groove 15 may be, for example, arc-shaped.
[0029] The bottom surface 17a is provided with a first mounting hole 11, a fifth mounting hole 12, and a sixth mounting hole 13. The number of the first mounting holes 11 is, for example, four. When viewed along the rotation axis A, the first mounting holes 11 are disposed at equal intervals along the rotation direction B of the rotary cutting tool 100. The number of the fifth mounting holes 12 and the sixth mounting holes 13 is, for example, eight. When viewed along the rotation axis A, the fifth mounting holes 12 and the sixth mounting holes 13 are disposed at equal intervals along the rotation direction B of the rotary cutting tool 100.
[0030] In the radial direction, the fifth mounting hole 12 is located outside the fitting portion 16. In the radial direction, the fifth mounting hole 12 is located inside the coolant reservoir groove 15. In the radial direction, the center of the fifth mounting hole 12 is located outside the center of the first mounting hole 11.
[0031] In the radial direction, the sixth mounting hole 13 is located outside the fitting portion 16. In the radial direction, the sixth mounting hole 13 is located outside the coolant reservoir groove 15. In the radial direction, the center of the sixth mounting hole 13 is located outside the center of the first mounting hole 11.
[0032] As shown in Fig. 4, the maximum diameter of the main body 1 is D1. The outer diameter of the coolant reservoir groove 15 is D2. The distance in the radial direction between the rotation axis A and the center of the first mounting hole 11 is R. The units of D1, D2, and R are mm. D1 satisfies Formula 1. D1 and D2 satisfy Formula 2. R and D2 satisfy Formula 3.
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[0036] D1 may be 200 mm or more, 250 mm or more, or 300 mm or more. D1 may be 650 mm or less, 600 mm or less, or 550 mm or less.
[0037] D2 may be 0.2 times or more than D1, or 0.3 times or more than D1. D2 may be 0.8 times or less than D1, or 0.6 times or less than D1. R is larger than the radius of the fitting portion 16. R is smaller than half the inner diameter of the coolant reservoir groove 15.
[0038] Fig. 5 is a schematic plan view showing the configuration of the cover 2. As shown in Fig. 5, the cover 2 has an opposing surface 25 that faces the main body 1. The diameter of the cover 2 is D4. D4 is smaller than D1 and larger than D2. The cover 2 has a recess 24. The recess 24 opens to the opposing surface 25. The recess 24 does not open to the surface opposite the opposing surface 25. In other words, the recess 24 is a hole having a bottom.
[0039] As shown in Fig. 5, when viewed along the rotation axis A, the recess 24 is, for example, cross-shaped. The recess 24 intersects with the rotation axis A. The recess 24 extends radially from the rotation axis A. The center of the cross-shaped recess 24 is located on the rotation axis A. The recess 24 is a flow path that sends coolant to the coolant reservoir groove 15. The shape of the recess 24 is not limited to a cross. The recess 24 may be, for example, linear.
[0040] 5, the opposing surface 25 is provided with second mounting holes 22, third mounting holes 23, and fourth mounting holes 21. The number of each of the second mounting holes 22 and third mounting holes 23 is, for example, eight. When viewed along the rotation axis A, the second mounting holes 22 and the third mounting holes 23 are disposed at equal intervals along the rotation direction B of the rotary cutting tool 100. The number of the fourth mounting holes 21 is, for example, four. When viewed along the rotation axis A, the fourth mounting holes 21 are disposed at equal intervals along the rotation direction B of the rotary cutting tool 100.
[0041] 6 is a plan view schematic perspective view showing a state in which the cover 2 is attached to the main body 1. In the radial direction, the second mounting hole 22 and the fourth mounting hole 21 are each located on the inner side of the coolant reservoir groove 15. In the radial direction, the third mounting hole 23 is located on the outer side of the coolant reservoir groove 15.
[0042] 6, when viewed along the rotation axis A, the recess 24 overlaps with each of the fitting portion 16 and the coolant reservoir groove 15. The first mounting hole 11, the second mounting hole 22, and the third mounting hole 23 overlap with the fourth mounting hole 21, the fifth mounting hole 12, and the sixth mounting hole 13, respectively. The first mounting hole 11, the second mounting hole 22, the third mounting hole 23, the fourth mounting hole 21, the fifth mounting hole 12, and the sixth mounting hole 13 do not overlap with the recess 24.
[0043] Coolant holes 14 are provided in the main body 1. The coolant holes 14 open to an outer peripheral surface 33 of the main body 1. The coolant holes 14 communicate with a coolant reservoir groove 15. The coolant holes 14 extend from the coolant reservoir groove 15 to the outer peripheral surface 33. The coolant is discharged from the coolant holes 14 to the outside. The number of the coolant holes 14 is, for example, 10. When viewed along the rotation axis A, the openings of the coolant holes 14 in the outer peripheral surface 33 may be provided at equal intervals in the rotation direction B.
[0044] The outer peripheral surface 33 is provided with an outer peripheral groove 33a, an insert arrangement groove 33b, and an outermost peripheral surface portion 33c. In the radial direction, the outer peripheral groove 33a is located inside the outermost peripheral surface portion 33c. The coolant hole 14 opens at the bottom of the outer peripheral groove 33a. The cutting insert 4 is arranged in the insert arrangement groove 33b. The cutting insert 4 is attached to the outer peripheral surface 33 of the main body portion 1 by using the insert fastening portion 3.
[0045] The inner diameter of the coolant hole 14 is defined as D3. The length of the coolant hole 14 as viewed in the direction along the rotation axis A is defined as L. The units of D3 and L are mm. D3 satisfies the mathematical formula 4. D3 and L satisfy the mathematical formula 5. The length of the coolant hole 14 is defined as the maximum length of the inner wall that constitutes the coolant hole 14.
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[0048] D3 may be 1.2 mm or more, or may be 1.4 mm or more. D3 may be 2.8 mm or less, or may be 2.6 mm or less. L / D3 may be 12 or more, or may be 14 or more. L / D3 may be 28 or less, or may be 26 or less.
[0049] 7 is a first cross-sectional schematic diagram showing a state in which the holder 7 is attached to the rotary cutting tool 100. The first cross section is a plane that is parallel to the rotation axis A and does not include the rotation axis A and intersects the two bolts 41.
[0050] 7, the retainer 7 is provided with a bolt insertion hole 9. The bolt 41 is fastened to the retainer 7 through the bolt insertion hole 9. The bolt 41 fixes the main body 1 to the retainer 7. The bolt 41 is inserted into the first mounting hole 11. The bolt 41 passes through the first mounting hole 11 and reaches the bolt insertion hole 9.
[0051] 8 is a second cross-sectional schematic diagram showing a state in which the holder 7 is attached to the rotary cutting tool 100. The second cross section is parallel to the rotation axis A and is a plane including the rotation axis A.
[0052] As shown in FIG. 8, the holder 7 has a first region 7a and a second region 7b. The second region 7b is continuous with the first region 7a. The outer diameter of the first region 7a is larger than the outer diameter of the second region 7b. The second region 7b protrudes from an end face of the first region 7a. The second region 7b is inserted into the fitting portion 16. The front end face of the first region 7a may contact the protruding portion 5. The outer peripheral surface of the second region 7b may contact the inner peripheral surface of the protruding portion 5. The holder 7 is provided with a coolant introduction hole 7c. The coolant introduction hole 7c penetrates each of the first region 7a and the second region 7b.
[0053] The arrows shown in FIG. 8 indicate the flow of the coolant. The coolant is introduced into the coolant introduction hole 7c provided in the holder 7. The coolant is introduced from the holder 7 into the fitting portion 16 of the main body 1. After passing through the fitting portion 16, the coolant flows toward the recess 24 provided in the cover 2. The coolant flows through the recess 24 toward the coolant reservoir groove 15. The coolant flows through the coolant reservoir groove 15 toward the coolant hole 14. The coolant is discharged to the outside of the main body 1 through the coolant hole 14.
[0054] FIG. 9 is a schematic perspective view showing a state in which a workpiece is being machined using the rotary cutting tool 100. As shown in FIG.
[0055] As shown in FIG. 9, the rotary cutting tool 100 is attached to a holder 7. The holder 7 is, for example, an arbor. A plurality of cutting inserts 4 are attached to the outer peripheral surface 33 of the main body 1 of the rotary cutting tool 100. When the holder 7 rotates, the rotary cutting tool 100 rotates around the rotation axis A. The rotary cutting tool 100 can move along a plane perpendicular to the rotation axis A while rotating around the rotation axis A. The workpiece 60 is cut by the cutting inserts 4. During cutting, coolant is discharged from a coolant hole 14 provided in the main body 1 toward the cutting inserts 4.
[0056] Next, the effects of the rotary cutting tool 100 according to this embodiment will be described. According to the rotary cutting tool 100 of this embodiment, if the maximum diameter of the main body 1 is D1, the outer diameter of the coolant reservoir groove 15 is D2, the distance between the rotation axis A and the center of the first mounting hole 11 in the radial direction is R, and D1, D2, and R are in mm, D1 satisfies the formula 1, D1 and D2 satisfies the formula 2, and R and D2 satisfies the formula 3. This makes it possible to provide a large-diameter rotary cutting tool 100 capable of supplying coolant from inside the main body 1. Specifically, by making D2 and R satisfy the formula 3, the coolant reservoir groove 15 can be formed outside the first mounting hole 11. Furthermore, by making D1 satisfy the formula 1, and making D1 and D2 satisfy the formula 2, when a long drill is used to form the coolant hole 14 in the main body 1, the long drill can be prevented from breaking and the coolant hole 14 can be formed in the main body 1.
[0057] According to the rotary cutting tool 100 of this embodiment, if the inner diameter of the coolant hole 14 is D3 and the length of the coolant hole 14 viewed along the rotation axis A is L, and the units of D3 and L are mm, D3 satisfies Formula 4, and D3 and L may also satisfy Formula 5. This makes it possible to reduce breakage of the long drill when forming the coolant hole 14 in the rotary cutting tool 100 using the long drill.
[0058] According to the rotary cutting tool 100 of this embodiment, the recess 24 may be cross-shaped when viewed along the rotation axis A. This allows the coolant to be evenly sent toward the coolant reservoir groove 15. Also, the recess 24 can be formed in the cover 2 so as not to overlap with the first mounting hole 11 into which the bolt 41 is inserted.
[0059] According to the rotary cutting tool 100 of this embodiment, the second mounting hole 22 may be located radially inward of the coolant reservoir groove 15. This can reduce leakage of the coolant from the gap between the main body 1 and the cover 2 even when the coolant pressure is high (for example, 7 MPa or more and 10 MPa or less). Therefore, the coolant can be effectively supplied to the cutting insert 4 during cutting. As a result, the life of the cutting insert 4 can be extended.
[0060] According to the rotary cutting tool 100 of this embodiment, the third mounting hole 23 may be located radially outward of the coolant reservoir groove 15. This makes it possible to reduce leakage of the coolant from the gap between the main body 1 and the cover 2 even when the coolant pressure is high (for example, 7 MPa or more and 10 MPa or less). Therefore, the coolant can be effectively supplied to the cutting insert 4 during cutting. As a result, the life of the cutting insert 4 can be extended.
[0061] The embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is defined by the claims, not by the embodiments described above, and is intended to include the equivalent meanings of the claims and all modifications within the scope of the claims. [Explanation of symbols]
[0062] 1 main body portion, 2 cover, 3 insert fastening portion, 4 cutting insert, 5 protrusion portion, 7 holder, 7a first region, 7b second region, 7c coolant introduction hole, 8 groove portion, 9 Bolt insertion hole, 11 first mounting hole, 12 fifth mounting hole, 13 sixth mounting hole, 14 coolant hole, 15 coolant reservoir groove, 16 fitting portion, 17 cover arrangement groove, 17a bottom surface, 17b inner peripheral surface, 21 fourth mounting hole, 22 second mounting hole, 23 third mounting hole, 24 recess, 25 opposing surface, 31 first side surface, 32 second side surface, 33 outer peripheral surface, 33a outer peripheral groove, 33b insert arrangement groove, 33c outermost peripheral surface portion, 41 Bolt, 42 inner placement screw, 43 outer placement screw, 44 cover set screw, 60 workpiece, 100 rotating cutting tool, A rotation axis, B rotation direction.
Claims
1. A rotary cutting tool rotatable around a rotation axis, a main body; a cover attached to the main body, The main body portion is provided with a fitting portion into which coolant is introduced and which is attached to a holder, a coolant reservoir groove located radially outward of the fitting portion, a first mounting hole into which a bolt that fixes the main body portion to the holder is inserted, and a coolant hole that is connected to the coolant reservoir groove and discharges the coolant, The cover is provided with a recess for directing the coolant to the coolant reservoir groove, A rotary cutting tool wherein D1 is a maximum diameter of the main body portion, D2 is an outer diameter of the coolant reservoir groove, R is a distance in the radial direction between the rotation axis and the center of the first mounting hole, and D1, D2, and R are all in mm, D1 satisfies Formula 1, D1 and D2 satisfy Formula 2, and R and D2 satisfy Formula 3. [Equation 1] [Equation 2] [Equation 3]
2. 2. The rotary cutting tool of claim 1, wherein an inner diameter of the coolant hole is D3, a length of the coolant hole as viewed along the rotation axis is L, and D3 and L are expressed in mm, D3 satisfies Formula 4, and D3 and L satisfies Formula 5. [Equation 4] [Equation 5]
3. The rotary cutting tool according to claim 1 or 2, wherein the recess is cross-shaped when viewed along the rotation axis.
4. The cover is provided with a second mounting hole into which a screw is inserted to fix the cover to the main body portion, The rotary cutting tool according to claim 1 or 2, wherein the second mounting hole is located radially inward of the coolant reservoir groove.
5. The cover is provided with a third mounting hole into which a screw is inserted to fix the cover to the main body portion, The rotary cutting tool according to claim 1 or 2, wherein the third mounting hole is located radially outward of the coolant reservoir groove.