Cutting Edge of a Micro Tooth Milling Cutter and Micro Tooth Milling Cutter

Abstract

The present invention provides a cutting edge of a micro-tooth milling cutter and a micro-tooth milling cutter. The cutting edge takes the sum of the projection lengths of a right-handed cutting edge and a left-handed groove in the axial direction of the cutter as a cutting unit length L. The cutting unit length L includes the projection length L1 of the right-handed cutting edge in the axial direction of the cutter and the projection length L2 of the left-handed groove in the axial direction of the cutter, and the height difference L3 between two adjacent right-handed cutting edges in the axial direction; the right-handed helix angle β R ranges from 5 to 35°, and the left-handed helix angle β L ranges from 25 to 70°. The beneficial effects of the present invention are as follows: There is a clear logical relationship among the number of cutting edges, the left-handed helix angle, the right-handed helix angle, and the cutting edge length of the series of micro-tooth milling cutters of the present invention. The adjustment of parameters has a restrictive relationship, which can ensure the stability of the tool performance. And after adjusting the main parameters according to requirements, a series of micro-tooth milling cutters suitable for different machining conditions can be formed.

Description

Technical Field

[0001] The present invention relates to the technical field of machining, and in particular to a cutting edge of a micro-tooth milling cutter and a micro-tooth milling cutter. Background Art

[0002] Fiber-reinforced composites represented by carbon fiber-reinforced composites (CFRP) have the advantages of high specific strength, high specific stiffness, excellent fatigue resistance, corrosion resistance, etc., and are widely used in the fields of aerospace, wind power generation, rail transit, sports goods, etc. Fiber-reinforced composites are typical difficult-to-machine materials, and processing defects such as burrs, tears, and delaminations are extremely likely to occur during the machining process. These processing defects will seriously damage the mechanical properties of the materials, resulting in random and uncontrollable decreases in the load-bearing capacity, tensile strength, and fatigue life of the materials.

[0003] In the milling of carbon fiber composites, research needs to be carried out in three directions: tool structure, matrix material, and coating. In the existing solutions, a typical solution is to use a micro-tooth milling cutter to perform micro-element removal on the material to achieve a machining method of milling instead of grinding, thereby reducing material damage.

[0004] The common problem in the current solutions is the lack of consideration for the arrangement design of the micro-tooth structure. Jia Zhenyuan et al. from Dalian University of Technology invented the "Micro-tooth Arrangement Design Method for Suppressing Edge Breakage of the Cutting Edge of a Multi-edge Micro-tooth Milling Cutter", patent application number 201810495696.8, which invented a micro-tooth arrangement design method to suppress the performance of the micro-tooth edge against chipping and wear and improve the tool life and cutting performance. Wang Fujie et al. from Dalian University of Technology invented the "Multi-tooth Design Scheme Capable of Realizing Alternate Cutting of Left- and Right-handed Cutting Edges", patent application number 201910075656.2, which invented a micro-tooth arrangement design method that can achieve a machining method in which the effective cutting parts of a multi-edge milling cutter perform alternate cutting of right-handed and left-handed cutting edges on different cross-sections, ensuring that the surface fibers of CFRP are continuously affected by axial forces in different directions, thereby achieving the purpose of suppressing the generation of surface burrs during high-speed milling of carbon fiber composites. However, the micro-tooth milling cutter designs in the above patents only optimize the design of adjacent two micro-tooth edges locally in the micro-tooth, without considering the micro-tooth design from the overall tool. The tool structure form is single, and there is no clear logical relationship between the parameters of the tool. A slight adjustment of some parameters will cause a large fluctuation in the tool performance. Summary of the Invention

[0005] The present invention provides a cutting edge of a micro-tooth milling cutter, including a cutting edge body, a left-handed groove, and a right-handed groove, and the left-handed helix angle is β L , and the right-handed helix angle is β R ;

[0006] When the cutting edge body is a right-handed edge, the right-handed groove is the main chip evacuation groove. The sum of the projected lengths of a right-handed edge and a left-handed groove in the tool axis direction is taken as a cutting unit length L. The cutting unit length L includes the projected length L1 of the right-handed edge in the tool axis direction and the projected length L2 of the left-handed groove in the tool axis direction, the height difference L3 between adjacent two right-handed edges in the axis direction, and the right-handed helix angle β R The range is 5 to 35°, and the left-handed helix angle β L The range is 25 to 70°;

[0007] When the cutting edge body is a left-handed edge, the left-handed groove is the main chip evacuation groove. The sum of the projected lengths of a left-handed edge and a right-handed groove in the tool axis direction is taken as a cutting unit length L. The cutting unit length L includes the projected length L1 of the left-handed edge in the tool axis direction and the projected length L2 of the right-handed groove in the tool axis direction, the height difference L3 between adjacent two left-handed edges in the axis direction, and the left-handed helix angle β L The range is 5 to 35°, and the right-handed helix angle β R The range is 25 to 70°;

[0008] The value range of L1 is (L-(n - 1)L3) to 0.75L, where n is the micro-tooth circumferential cycle period.

[0009] As a further improvement of the present invention, the right-handed helix angle β R + the left-handed helix angle β L ≥40°.

[0010] As a further improvement of the present invention, the number of right-handed grooves is Z R , and the number of left-handed grooves is Z L， The cutting edge diameter is D, and the unit of D is mm;

[0011] When the right-handed groove is the main chip evacuation groove, the selection range of the number of right-handed grooves Z R is:

[0012] 1 < D ≤ 3, Z R takes values 4 to 8;

[0013] 3 < D ≤ 6, Z R takes values 6 to 12;

[0014] 6 < D ≤ 10, Z R takes values 8 to 14;

[0015] 10 < D ≤ 20, Z R takes values 10 to 18;

[0016] When the left-handed groove is the main chip evacuation groove, the selection range of the number of left-handed grooves Z L is:

[0017] 1 < D ≤ 3, ZL The value ranges from 4 to 8;

[0018] 3 < D ≤ 6, Z L The value ranges from 6 to 12;

[0019] 6 < D ≤ 10, Z L The value ranges from 8 to 14;

[0020] 10 < D ≤ 20, Z L The value ranges from 10 to 18.

[0021] As a further improvement of the present invention, for the cutting edge diameter D, the value range of the cutting unit length L is (0.1 - 0.3)D.

[0022] As a further improvement of the present invention, the calculation formula for the micro - tooth circumferential cycle period n is as follows: (Z R , Z L ) is the greatest common divisor of the number of right - hand grooves Z R and the number of left - hand grooves Z L of.

[0023] As a further improvement of the present invention, the calculation formula for L3 is as follows: D is the cutting edge diameter.

[0024] As a further improvement of the present invention, when the cutting edge body is a right - hand cutting edge, the cutting edge diameter D = 10 mm, the right - hand helix angle β R = 15°, the left - hand helix angle β L = 40°, the number of right - hand grooves Z R = 12, the number of left - hand grooves Z L = 18, L = 1.58 mm, n = 2, L3 = 0.79 mm.

[0025] As a further improvement of the present invention, the value range of L1 is 0.79 - 1.19 mm.

[0026] As a further improvement of the present invention, L1 = 0.84 mm, L2 = 0.74 mm.

[0027] As a further improvement of the present invention, when the cutting edge body is a left - hand cutting edge, the cutting edge diameter D = 10 mm, the right - hand helix angle β R = 35°, the left - hand helix angle β L = 20°, the number of right - hand grooves Z R = 10, the number of left - hand grooves Z L = 12, L = 2.95 mm, n = 6, L3 = 0.49 mm.

[0028] As a further improvement of the present invention, the value range of L1 is 0.5 - 2.21 mm.

[0029] As a further improvement of the present invention, L1 = 1.8 mm and L2 = 1.15 mm.

[0030] The present invention also provides a micro-tooth milling cutter, which includes a tool shank, a transition section, and the cutting edge described in the present invention. The tool shank is connected to the transition section, and the transition section is connected to the cutting edge.

[0031] The beneficial effects of the present invention are as follows: There is a clear logical relationship among the number of teeth, the left-handed helix angle, the right-handed helix angle, and the cutting edge length of the series of micro-tooth milling cutters of the present invention. The adjustment of parameters has a restrictive relationship, which can ensure the stability of the tool performance. And after adjusting the main parameters according to the requirements, a series of micro-tooth milling cutters suitable for different machining conditions can be formed. Description of the Drawings

[0032] Figure 1 is a schematic structural diagram of a right-handed micro-tooth milling cutter;

[0033] Figure 2 is a schematic diagram of the right-handed micro-tooth arrangement;

[0034] Figure 3 is a schematic structural diagram of a left-handed micro-tooth milling cutter;

[0035] Figure 4 is a schematic diagram of the left-handed micro-tooth arrangement. Detailed Embodiments

[0036] The present invention discloses a micro-tooth milling cutter, which includes three parts: a cutting edge 10, a transition section 20, and a tool shank 30. The tool shank 30 is connected to the transition section 20, and the transition section 20 is connected to the cutting edge 10. The content involved in the present invention is in the cutting edge 10 part, and the main technical parameters include: the number of right-handed grooves, the right-handed helix angle, the number of left-handed grooves, the left-handed helix angle, and the projection length L1 of the right-handed cutting edge on the tool axis.

[0037] The cutting edge 10 includes a cutting edge body, a left-handed groove 13, and a right-handed groove 12.

[0038] As Figure 1 shown, when the cutting edge body is a right-handed cutting edge 11, the three-dimensional micro-tooth milling cutter structure is unfolded into a two-dimensional milling cutter micro-tooth structure arrangement diagram with the axis as the center, and a part of the effective cutting unit is intercepted as Figure 2 shown, the right-handed helix angle is β R , and the left-handed helix angle is β L, the sum of the projected lengths of a right-handed cutting edge 11 and a left-handed groove 13 in the axial direction of the tool (the tool refers to the micro-tooth milling cutter of the present invention) is taken as the length L of a cutting unit, which includes the projected length L1 of the right-handed cutting edge 11 in the axial direction of the tool and the projected length L2 of the left-handed groove 13 in the axial direction of the tool, and the height difference L3 between two adjacent right-handed cutting edges 11 in the axial direction. The cutting edge diameter of the tool is D, and the number of right-handed grooves is Z R , the number of left-handed grooves is Z L .

[0039] Right-handed helix angle β R ranges from 5 to 35°, β L ranges from 25 to 70°. At the same time, in order to ensure the strength of the micro-tooth tip angle, it is necessary to ensure that β R +β L ≥40°.

[0040] Number of right-handed grooves Z R is selected according to the cutting edge diameter of the tool and the tool processing parameters. The selection range of Z R is shown in the following table. Within a certain range, the chip evacuation groove chip capacity and the micro-tooth strength of the tool can be adjusted by the number of right-handed cutting edges to adapt to different composite material processing:

[0041] Table 1 Number of right-handed grooves Z R Selection range

[0042]

[0043] Number of left-handed grooves Z L determines the cutting unit length L. The cutting unit length L ranges from (0.1 to 0.3)D. Generally, in the case of higher material fiber strength and easy generation of processing defects, it is suitable to select a smaller unit length.

[0044] The selection of the length L1 of the right-handed cutting edge needs to satisfy the full coverage of the right-handed cutting edge 11 in the axial direction of the tool. The range of L1 is (L-(n-1)L3) to 0.75L.

[0045] where n is the circumferential cycle period of the micro-teeth, which is affected by the ratio of the number of left-handed grooves Z L and the number of right-handed grooves Z R . Generally, under a larger feed, when the micro-teeth of the tool need to bear a larger cutting force, the number of circumferential cycle periods n of the micro-teeth should be taken as a smaller value. The calculation formula is as follows:

[0046]

[0047] L3 is the height difference between two adjacent right-handed cutting edges 11 in the axial direction. The calculation formula is as follows:

[0048]

[0049] Explanation: (Z R , Z L ) is the greatest common divisor of Z R and Z L .

[0050] As shown in Figure 3 and 4 , when the cutting edge body is the left-handed edge 14, the sum of the projected lengths of a left-handed edge 14 and a right-handed groove 12 in the tool axis direction is taken as a cutting unit length L, where the cutting unit length L includes the projected length L1 of the left-handed edge 14 in the tool axis direction and the projected length L2 of the right-handed groove 12 in the tool axis direction, the height difference L3 between adjacent left-handed edges 14 in the axis direction, and the right-handed helix angle β R ranges from 25 to 70°, and the left-handed helix angle β L ranges from 5 to 35°. The left-handed groove 13 is the main chip removal groove.

[0051] As the first preferred embodiment of the present invention:

[0052] The tool in this embodiment is right-handed and right-cutting, and the right-handed groove is the main chip removal groove.

[0053] The processing material object is the high-strength carbon fiber reinforced composite material T800;

[0054] The cutting edge diameter D = 10 mm;

[0055] The right-handed helix angle β R = 15°;

[0056] The left-handed helix angle β L = 40°;

[0057] The number of right-handed grooves Z R = 12;

[0058] The number of left-handed grooves Z L = 18;

[0059] L = 1.58 mm;

[0060] L1 = 0.84 mm;

[0061] L2 = 0.74 mm.

[0062] In this first preferred embodiment, the tool cutting life verification was carried out at the user site. Under the processing parameters of a rotational speed of 8000 rpm and a feed of 1000 mm / min, when grooving a 4-mm-thick T300 CFRP copper clad laminate, the tool life is shown in Table 2. Compared with domestic and foreign competing products, the tool life has increased by more than 50%, and the advantage is obvious.

[0063] Table 2 Comparison test results of tool life

[0064]

[0065] As the second preferred embodiment of the present invention:

[0066] The cutting tool in this embodiment is left-handed and right-cutting, and the left-handed groove is the main chip removal groove.

[0067] The processing material object is a glass fiber reinforced composite material;

[0068] The cutting edge diameter D = 10 mm;

[0069] The left-handed helix angle β L = 20°;

[0070] The right-handed helix angle β R = 35°;

[0071] The number of left-handed grooves Z L = 12;

[0072] The number of right-handed grooves Z R = 10;

[0073] L = 2.95 mm;

[0074] L1 = 1.8 mm;

[0075] Then L2 = 1.15 mm.

[0076] The above content is a further detailed description of the present invention in combination with specific preferred embodiments. It cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, without departing from the concept of the present invention, several simple deductions or substitutions can be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. The cutting edge of a micro-tooth milling cutter, characterized in that: Including a cutting edge body, a left-handed groove, and a right-handed groove, with a left-handed helix angle of β L , and a right-handed helix angle of β R ; When the cutting edge body is a right-handed edge, the right-handed groove is the main chip evacuation groove. The sum of the projected lengths of a right-handed edge and a left-handed groove in the tool axis direction is taken as the cutting unit length L. The cutting unit length L includes the projected length L1 of the right-handed edge in the tool axis direction and the projected length L2 of the left-handed groove in the tool axis direction, the height difference L3 between adjacent right-handed edges in the axis direction, and the right-handed helix angle β R ranges from 5 to 35°, and the left-handed helix angle β L ranges from 25 to 70°; When the cutting edge body is a left-handed edge, the left-handed groove is the main chip evacuation groove. The sum of the projected lengths of a left-handed edge and a right-handed groove in the tool axis direction is taken as a cutting unit length L. The cutting unit length L includes the projected length L1 of the left-handed edge in the tool axis direction and the projected length L2 of the right-handed groove in the tool axis direction, the height difference L3 between adjacent two left-handed edges in the axis direction, and the left-handed helix angle β L ranges from 5 to 35°, and the right-handed helix angle β R ranges from 25 to 70°; The value range of L1 is (L - (n - 1)L3) to 0.75L, where n is the circumferential cycle period of the micro teeth; The calculation formula for the micro-tooth circumferential cycle period n is as follows: (Z R , Z L ) is the greatest common divisor of the number of right-handed grooves Z R and the number of left-handed grooves Z L .

2. The cutting edge according to claim 1, characterized in that: Right-handed helix angle β R + Left-handed helix angle β L ≥ 40°.

3. The cutting edge according to claim 1, characterized in that: The number of right-handed grooves is Z R , and the number of left-handed grooves is Z L， The cutting edge diameter is D, and the unit of D is mm; When the right-handed groove is the main chip removal groove, the number of right-handed grooves Z R is selected within the range of: 1 < D ≤ 3, Z R takes values from 4 to 8; 3 < D ≤ 6, Z R The value ranges from 6 to 12; 6 < D ≤ 10, Z R takes values from 8 to 14; 10 < D ≤ 20, Z R takes values from 10 to 18; When the left-handed groove is the main chip evacuation groove, the selection range of the number of left-handed grooves Z L is as follows: 1 < D ≤ 3, Z L takes values from 4 to 8; 3 < D ≤ 6, Z L takes values from 6 to 12; 6 < D ≤ 10, Z L takes values from 8 to 14; 10 < D ≤ 20, Z L takes values from 10 to 18.

4. The cutting edge according to claim 1, wherein: The cutting edge diameter is D, and the value range of the cutting unit length L is (0.1 to 0.3)D.

5. The cutting edge according to claim 1, characterized in that: The calculation formula of L3 is as follows: D is the cutting diameter.

6. The cutting edge according to claim 1, characterized in that: When the cutting edge body is a right-handed edge, the cutting edge diameter D = 10 mm, the right-handed helix angle β R = 15°, the left-handed helix angle β L = 40°, the right-handed groove number Z R = 12, the left-handed groove number Z L = 18, L = 1.58 mm, n = 2, L3 = 0.79 mm.

7. The cutting edge according to claim 6, characterized in that: The value range of L1 is 0.79 to 1.19 mm.

8. The cutting edge according to claim 7, characterized in that: L1 = 0.84 mm, and L2 = 0.74 mm.

9. The cutting edge according to claim 1, wherein: When the cutting edge body is a left-handed edge, the cutting edge diameter D = 10 mm, the right-handed helix angle β R = 35°, the left-handed helix angle β L = 20°, the right-handed flute number Z R = 10, the left-handed flute number Z L = 12, L = 2.95 mm, n = 6, L3 = 0.49 mm.

10. The cutting edge according to claim 9, characterized in that: The value range of L1 is 0.5 to 2.21 mm.

11. The cutting edge according to claim 10, characterized in that: L1 = 1.8 mm, and L2 = 1.15 mm.

12. A micro-tooth milling cutter, characterized in that: It includes a tool shank, a transition section, and the cutting edge according to any one of claims 1 to 11, the tool shank is connected to the transition section, and the transition section is connected to the cutting edge.

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