CN112676628A

CN112676628A - Variable-graduation three-edge milling cutter with protective edge and finishing edge

Info

Publication number: CN112676628A
Application number: CN202110050761.8A
Authority: CN
Inventors: 谢叶飞
Original assignee: Astor Precision Tools Shanghai Co ltd
Current assignee: Astor Precision Tools Shanghai Co ltd
Priority date: 2021-01-14
Filing date: 2021-01-14
Publication date: 2021-04-20

Abstract

The invention discloses a variable-resolution three-edge milling cutter with a protective edge and a finishing edge, which comprises a cutter body, wherein the cutter body comprises a handle part and a cutting part, the cutting part is provided with three circumferential edges, a chip discharge groove is arranged between the adjacent circumferential edges, the circumferential edges and the chip discharge grooves spirally extend around the outer side wall of the cutting part, and the chip discharge grooves are distributed on the outer side wall of the cutting part in a non-equal way; the peripheral edge extends to the front end of the cutting part to form three end edges, and a chip groove is formed between the adjacent end edges; a protective knife edge is arranged in the chip groove; the end blade is provided with an end blade rear blade face, and the end blade rear blade face is provided with a smoothing blade. The chip grooves are designed unequally, resonance in the machining process of the end mill is eliminated, and the anti-collapse capability of the cutter is stronger; the edge of the cutter is protected, the strength of the cutting edge of the peripheral edge is increased, the friction between chips and the front cutter face is reduced, and the peripheral edge is prevented from being broken; increase the smoothing sword, the processing is handed over to the level and smooth of a plurality of blades, reduces roughness, strengthens milling cutter's wearability, improves cutter life.

Description

Variable-graduation three-edge milling cutter with protective edge and finishing edge

Technical Field

The invention relates to a processing cutter, in particular to a variable-graduation three-edge milling cutter with a protective edge and a smoothing edge.

Background

Aiming at the processing of aluminum alloy materials, several three-edge milling cutters commonly used in the market at present are almost designed in a three-edge equal division mode, a single large groove front angle and a single large groove rear angle or arc ligaments are reserved, and end teeth are designed in a single-edge inclination angle mode. The advantages are that: the manufacturing is convenient, the rigidity of the cutter is good, but in the processing process, due to the halving design, the cutting vibration is easily generated in the processing process, so that the vibration lines are generated on the processing surface; although the cutting of a single large groove front angle is very sharp, the cutting edge is weak in rigidity and insufficient in strength due to lack of cutting edge protection, and the phenomenon of edge breakage is easy to occur; the design of two sharp relief angles is adopted to week tooth relief angle simultaneously, and cutting force can be little a lot, and cutting process is lighter and faster, but also has the cutting back knife face to support not enough, and the phenomenon of processing surface roughness difference, straight line relief angle and circular arc relief angle are compared simultaneously, and the bulk strength is weak slightly, and easy wearing and tearing, end tooth adopt the design of single-blade inclination, cut light and fast, and the cutting resistance is smaller, but also meets the poor problem of processing back roughness simultaneously. Therefore, the defects encountered in the machining process of the three-edge aluminum milling cutter on the market at present need to be analyzed, optimized and improved in design in a targeted manner.

Disclosure of Invention

The invention aims to solve the technical problem of providing a variable-graduation three-edge milling cutter with a protective edge and a smoothing edge, and solves the problems that the existing three-edge milling cutter generates vibration lines due to cutting vibration, is easy to break edges and has poor roughness of the processing surfaces of end edges and peripheral edges.

The invention provides a variable-graduation three-edge milling cutter with a protective edge and a smoothing edge for solving the technical problems, which comprises a cutter body, wherein the cutter body comprises a handle part and a cutting part, the cutting part is provided with three circumferential edges, a chip removal groove is arranged between every two adjacent circumferential edges, the circumferential edges and the chip removal groove spirally extend around the outer side wall of the cutting part, and the chip removal grooves are distributed on the outer side wall of the cutting part in a non-equal distribution manner; the peripheral edge extends to the front end of the cutting part to form three end edges, and a chip groove is formed between the adjacent end edges; the chip groove is communicated with the chip groove; a protective knife edge is arranged in the chip groove; the end blade is provided with an end blade rear blade face, and the end blade rear blade face is provided with a smoothing blade.

Further, the non-equal distribution of the division difference of the chip grooves on the outer side wall of the cutting part is 10-13 degrees.

Further, the chip flutes are distributed unequally on the cutting portion front end surface, the end edges are divided into an over-center first end edge and a non-over-center second end edge and a non-over-center third end edge, and the chip flutes are divided into an over-center first chip flute and a non-over-center second chip flute and a non-over-center third chip flute.

Further, the peripheral edge forms a peripheral edge rake angle RA1 of 14-16 °; the protection tool edge is arranged on the wall surface of the chip groove facing the rotation direction of the tool body, the protection tool edge front angle RAA formed by the protection tool edge is 7-9 degrees, and the width LRA of the protection tool edge is 0.1-0.5 mm.

Further, an end edge clearance angle WQ1 of the end edge rear cutter face is 3-5 degrees, the finishing edge is arranged at the position, close to the peripheral edge, of the end edge rear cutter face, the finishing edge clearance angle WQ2 is 0.1-0.5 degrees, and the width of the finishing edge is 0.1-1.0 mm.

Furthermore, the peripheral edge is provided with a circular arc-shaped peripheral edge rear cutter face, the rear angle formed by the peripheral edge rear cutter face is 2-5 degrees, and the width of the peripheral edge rear cutter face is 0.04-0.3 mm.

Further, the flute helix angle WA is 35 to 40.

Further, the cutter main body is made of hard alloy.

Compared with the prior art, the invention has the following beneficial effects: according to the variable-division three-edge milling cutter with the protective edge and the smoothing edge, the chip grooves are designed in an unequal manner, resonance in the processing process of the end milling cutter is eliminated, processing vibration is reduced, and the anti-collapse capability of the cutter is stronger; the cutter edge is protected, the strength of the cutting edge of the peripheral edge is increased, the contact length and the tangential force between the cutting edge and chips are reduced, the friction effect between the chips and a front cutter face is reduced, and the phenomenon that the peripheral edge of the milling cutter is cracked when large allowance is cut is prevented; increase the smoothing sword, the processing is handed over to the level and smooth of a plurality of blades, reduces the roughness of work piece, strengthens milling cutter's wearability effectively, and length and life are long when improving the operation of cutter.

Drawings

FIG. 1 is a schematic structural view of a variable-graduation three-edge milling cutter with a protective edge and a smoothing edge according to an embodiment of the invention;

FIG. 2 is a cross-sectional view of a variable-index three-edged milling cutter with a protective cutting edge and a wiper edge in an embodiment of the present invention;

FIG. 3 is a side view of a variable index three-edged milling cutter with a protective cutting edge and a wiper edge in an embodiment of the present invention;

FIG. 4 is an enlarged view of a cutting portion in an embodiment of the present invention;

in the figure:

1. a handle; 2. a cutting portion; 3. a peripheral edge; 4. a chip groove; 5. an end blade; 6. a chip pocket; 7. protecting the knife edge; 8. an end blade flank; 9. smoothing the edge; 10. a peripheral edge relief surface; 51. a first end blade; 52. a second end blade; 53. a third end blade; 61. a first chip pocket; 62. a second chip pocket; 63. a third chip pocket; WA, flute helix angle; A1/A2/A3, flute index angle; RA1, peripheral edge rake angle; RAA, protecting a rake angle of a knife edge; LRA, protecting the width of the knife edge; WQ1, end edge relief angle; WQ2, wiper edge relief angle.

Detailed Description

The invention is further described below with reference to the figures and examples.

FIG. 1 is a schematic structural view of a variable-graduation three-edge milling cutter with a protective edge and a smoothing edge according to an embodiment of the invention; fig. 2 is a cross-sectional view of a variable-index three-edge milling cutter with a protective cutting edge and a wiper edge in an embodiment of the invention.

Referring to fig. 1 and 2, the variable-division three-edge milling cutter with the protective cutting edge and the smoothing edge according to the embodiment of the invention comprises a cutter body, wherein the cutter body comprises a shank 1 and a cutting part 2, the cutting part 2 is provided with three peripheral edges 3, a chip discharge groove 4 is arranged between adjacent peripheral edges 3, the peripheral edges 3 and the chip discharge groove 4 spirally extend around the outer side wall of the cutting part 2, and the chip discharge grooves 4 are non-equally distributed on the outer side wall of the cutting part 2; the peripheral edge 3 extends to the front end of the cutting part 2 to form three end edges 5, and chip flutes 6 are formed between the adjacent end edges 5; the chip groove 6 is communicated with the chip groove 4; a protective knife edge 7 is arranged in the chip groove 4; the end blade 5 is formed with an end blade flank 8, which is provided with a wiper blade 9.

With reference to fig. 2, in the variable-graduation three-edge milling cutter with the protective cutting edge and the smoothing edge according to the embodiment of the present invention, the division angles corresponding to the chip groove 4 are a1, a2 and A3, respectively, wherein a1 is not equal to a2 is not equal to A3, and the division difference of the chip groove 4 in the non-uniform distribution on the outer side wall of the cutting portion 2 is 10 ° to 13 °; when the cutter rotates at a high speed and uses the peripheral edge 3 to process an aluminum piece, because the graduation is unequal, each cutting edge cuts into a material and leaves a workpiece material at different time intervals, the generated cutting force is not generated at fixed time intervals and is transmitted and superposed to the same wave, the superposition and resonance of the force are avoided, the resonance in the milling cutter processing process can be eliminated through the unequal design, the processing vibration is reduced, and the anti-collapse capability of the cutter is stronger.

Specifically, the peripheral edge 3 forms a peripheral edge rake angle RA1 of 14 ° to 16 °; the protective cutting edge 7 is arranged on the wall surface of the chip groove 4 facing the rotation direction of the cutter body, the protective cutting edge rake angle RAA formed by the protective cutting edge 7 is 7-9 degrees, and the width LRA of the protective cutting edge is 0.1-0.5 mm. The peripheral edge rake angle RA1 is the flute rake angle of the chip groove 4, since aluminum alloy is soft material, when machining, it is desirable to use a sharp cutting edge with a large rake angle to machine, so that a very high metal removal rate can be obtained, but the sharp rake cutting edge means a relatively weak cutting strength, so that during machining, because of poor cutting edge strength, a cutting edge chipping or plastic deformation occurs again, in order to find an optimal balance point between sharpness and strength, a protection edge 7 is added in the chip groove 4, the rake angle RAA of the protection edge 7 is smaller, so that the sharpness of a point cutting edge is slightly reduced, but the strength of the cutting edge is greatly enhanced, and through experiments and application, the angle of the protection edge 7 is found to be between 7 and 9 degrees, the width is found to be between 0.1 and 0.5, and the optimal balance between sharpness and strength is obtained; the specific numerical value is comprehensively determined according to the diameter of the cutter and the silicon content of the aluminum alloy material. The protection arris 7 protects the 3 blade intensity of peripheral sword, reduces the contact length and the tangential force of cutting edge and smear metal, reduces the frictional action of smear metal and rake face, prevents when the cutting of big surplus, and the peripheral sword 3 of milling cutter takes place to collapse and lacks the phenomenon.

Specifically, the peripheral edge 3 is formed with a circular arc-shaped peripheral edge flank 10, the clearance angle formed by the peripheral edge flank 10 is 2 ° to 5 °, and the width of the peripheral edge flank 10 is 0.04 mm to 0.3 mm. The peripheral edge rear cutter face 10 enhances the strength of the peripheral edge 3, can improve the durability of the milling cutter, increases the contact area between the peripheral edge 3 and the processing surface, has the functions of supporting, guiding, stabilizing and eliminating vibration, and has a certain ironing effect on the regular and smooth peripheral edge rear cutter face 10 to improve the quality of the processing surface.

Referring to fig. 3, in the variable-division three-edge milling cutter with the protective cutting edge and the wiper edge according to the embodiment of the present invention, the chip flutes 6 are distributed on the front end surface of the cutting portion 2 in a non-equal manner, the end edges 5 are divided into the first over-center chip flutes 51 and the second and third over-center

chips

52 and 53, and the chip flutes 6 are divided into the first over-center chip flutes 61 and the second and third over-center

chips

62 and 63. The different rake angles of the chip flutes 6 cause different cutting resistances, reducing vibrations. By adopting the design of unequal chip-containing grooves 6, the vibration generated by cutting processing is effectively reduced, and the chip-containing space is ensured.

Referring to fig. 4, in the variable-degree three-edge milling cutter with the protective cutting edge and the wiper edge according to the embodiment of the present invention, an end edge relief angle WQ1 of an end edge flank 8 is 3 ° to 5 °, the wiper edge 9 is disposed at a position close to the peripheral edge 3 on the end edge flank 8, a relief angle WQ2 of the wiper edge 9 is 0.1 ° to 0.5 °, and a width of the wiper edge 9 is 0.1 mm to 1.0 mm. The end edge back angle WQ1 is the inclination angle value of the milling cutter edge processed by the conventional aluminum alloy, and is between 3 degrees and 5 degrees, and the inclination angle of the edge can lead the end edge to participate in the cutting with smaller contact area in the processing process, thereby leading the cutting to be very light and fast, leading the feeding to be also large and achieving larger metal cutting rate in unit time. However, the large edge inclination angle causes the surface roughness of the processed workpiece to be less ideal, and in order to obtain better roughness at the same time, a wiper edge is added on the end edge flank 8, the wiper edge relief angle WQ2 is set to be 0.1-0.5 degrees, and the width of the wiper edge 9 is 0.1-1.0 mm. The polishing edge 9 adds the contact area between the milling cutter and a processed workpiece, so that the effect of common processing of a plurality of cutting edges is formed, and the wear resistance of the milling cutter is improved; meanwhile, the polishing edge 9 is added, so that the milling of the milling cutter is smoother during processing, the cutter is not easy to shake during large-allowance processing, the processing delay time caused by the shaking cutter is reduced, and the efficiency is improved; meanwhile, because the aluminum material is soft, the traditional milling cutter is easy to be stained with a cutter in the processing process, and scratches and color difference are easily caused in the processing process. Through the design that increases smoothing sword 9, the processing is handed over smoothly to a plurality of blades, is consequently difficult to be stained with the sword, and the effectual roughness that has reduced the work piece has reduced scratch and colour difference.

Preferably, the flutes 4 have a helix angle WA of 35 to 40, a high angle helix angle facilitating chip evacuation.

Preferably, the cutter main body is made of hard alloy, and high-light high-precision machining operation is facilitated due to the high hardness and wear resistance of the hard alloy material.

In conclusion, the variable-fraction three-edge milling cutter with the protective edge and the smoothing edge of the embodiment of the invention has the advantages that the chip groove 4 is designed in an unequal manner, resonance in the processing process of the end mill is eliminated, processing vibration is reduced, and the anti-collapse capability of the cutter is stronger; the cutter edge 7 is protected to increase the strength of the cutting edge of the peripheral edge 3, the contact length and the tangential force between the cutting edge and chips are reduced, the friction between the chips and the front cutter face is reduced, and the peripheral edge 3 of the milling cutter is prevented from collapsing when large allowance is cut; increase and repair smooth sword 9, the processing is handed over to the smoothness of a plurality of blade, reduces the roughness of work piece, strengthens milling cutter's wearability effectively, and length and life are long when improving the operation of cutter.

Although the present invention has been described with respect to the preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The variable-graduation three-edge milling cutter with the protective edge and the smoothing edge is characterized by comprising a cutter body, wherein the cutter body comprises a handle part and a cutting part, the cutting part is provided with three circumferential edges, a chip discharge groove is formed between every two adjacent circumferential edges, the circumferential edges and the chip discharge grooves spirally extend around the outer side wall of the cutting part, and the chip discharge grooves are distributed on the outer side wall of the cutting part in a non-equal manner; the peripheral edge extends to the front end of the cutting part to form three end edges, and a chip groove is formed between the adjacent end edges; the chip groove is communicated with the chip groove; a protective knife edge is arranged in the chip groove; the end blade is provided with an end blade rear blade face, and the end blade rear blade face is provided with a smoothing blade.

2. The variable-index three-edge milling cutter with the protective cutting edge and the wiper edge as claimed in claim 1, wherein the non-equally distributed index difference of the chip grooves on the outer side wall of the cutting portion is 10 ° to 13 °.

3. The variable-division three-edge milling cutter with the protective cutting edge and the wiper edge as set forth in claim 1, wherein the chip flutes are distributed unequally on the cutting portion front end surface, the end edges are divided into an overcenter first end edge and an overcenter second end edge and a third end edge, and the chip flutes are divided into an overcenter first chip flute and an overcenter second chip flute and a third chip flute.

4. The variable-index three-edged milling cutter with a guard edge and a wiper edge as set forth in claim 1, wherein the peripheral edge forms a peripheral edge rake angle RA1 of 14 ° to 16 °; the protection tool edge is arranged on the wall surface of the chip groove facing the rotation direction of the tool body, the protection tool edge front angle RAA formed by the protection tool edge is 7-9 degrees, and the width LRA of the protection tool edge is 0.1-0.5 mm.

5. The varied-degree three-edge milling cutter with the protective cutting edge and the wiper edge as claimed in claim 1, wherein the end edge relief angle WQ1 of the end edge flank face is 3 ° to 5 °, the wiper edge is disposed at the end edge flank face near the peripheral edge, the wiper edge relief angle WQ2 is 0.1 ° to 0.5 °, and the width of the wiper edge is 0.1 to 1.0 mm.

6. The varied-degree three-edge milling cutter with the protective cutting edge and the wiper edge as set forth in claim 1, wherein the peripheral edge is formed with a peripheral edge relief surface having a circular arc shape, the peripheral edge relief surface is formed with a relief angle of 2 ° to 5 °, and the width of the peripheral edge relief surface is 0.04 to 0.3 mm.

7. The variable-index three-edge milling cutter with a protective cutting edge and a wiper edge as claimed in claim 1, wherein the flute helix angle WA is from 35 ° to 40 °.

8. The variable-index three-edge milling cutter with the protective cutting edge and the wiper edge as set forth in claim 1, wherein the cutter body is made of cemented carbide.