JPS6334010A - Roughing end mill - Google Patents

Abstract

PURPOSE:To decrease a cutting burden per one full rotation and to increase a life, by a method wherein a cutting section is divided radially in addition to a radial direction in a way that the waveform cutting baldes of a blade part situated along a groove are orderly displaced in a phase by a length shown by a specified formula at each blade part. CONSTITUTION:Cutting blades in a waveform with a pitch P' at each blade part at an end mill, being, for example, 6 (I VI) in the number of blade parts, are positioned in a manner that phases are displaced, in order, by (P'/6X2). In the size, in a radial direction on a line D-D' of cross section extending at right angles with an axis, of a waveform cutting blade 5 based on an apex T of a blade part I, the sizes of the blade parts I and IV are equal to an outer size virtual line L, that of a blade part II is minus (a), and that of a blade part III is minus (b). Thus, since two or more cutting blades, having the same size and same shape to each other, appear on a cross section extending at right angles with an axis in the arbitrary position of the blade part, a cutting cross section is divided radially in addition to an axial direction, a cutting quantity per one cutting blade is reduced to 1/2 that of a conventional type, wear of a cutting blade is also reduced, and a life can be sharply increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a roughing end mill in which a corrugated cutting edge is formed along a helical groove formed on the outer periphery of a main body.

(Prior art) A general roughing end mill is shown in Fig. 1 and enlarged in Fig. 2. When viewed in the direction of the arrow in Fig. 2, that is, from the rake face, the pitch (P) is the radius (R). A corrugated cutting edge with
By the way, in the conventional roughing end mill, the position of the corrugated cutting edge is sequentially shifted in phase for each blade part (3). The phase amount is "waveform pitch (p) ÷ number of blade parts (3) (N)", and in any axis-perpendicular cross section of the blade part, the radial dimension of each cutting edge is different, and the same-shaped chips There are no blades. This is shown in an axis-perpendicular cross-sectional view taken along the line A-A' in Figure 1.
As shown in FIG. 9, if the number of blade portions (3) is 6, a total of 6 blades will be formed from 1 blade to (1) to &6 blades. The dimensions of the A1 blade (1) are the same as the tool virtual diameter (4), but the dimensions from JFL2 blade (II) to Ni6 blade (VI) are the same as the tool virtual diameter (4).
4) Yo.

It is negative.

Fig. 10 is a developed view of this waveform cutting edge, and the positions of the waveform cutting edge from A1 blade (I) of the blade part (3); Q- to A6 blade (end) are sequentially phased. It is shifted. In this case, the phase amount for each blade is (pitch (p) ÷ number of blades (6 blades)
). The line D-D' is a cross section perpendicular to the axis of the end mill with reference to the apex (T) of the blade (1), but the radial dimension of each blade is 7!11 for the blade (1), which is the virtual tool diameter. line(
4), and from &2 blade (I [) to Ya6 blade (b) are (a), (b), (C), from the tool diameter virtual line (4),
Only (a) and (e) are negative. As is clear from this, the radial dimension of each waveform cutting edge and the cutting shape of the waveform on the axis-perpendicular section D-D' edge line are different for each blade portion (3). Note that the angle is the helix angle of the blade with respect to the axial direction of the end mill.

Furthermore, FIG. 11 shows a cutting action diagram (envelope line) when cutting is performed with the cutting feed rate e (F) per rotation of this roughing end mill. The hatched part on the drawing indicates the cutting cross-sectional area (PXF) per rotation of the end mill in the axial length corresponding to one pitch (P) of the corrugated cutting edge (5) of the end mill, It shows that cutting is performed using six wave-shaped cutting edges (5). Furthermore, from Fig. 11 to Fig. 15, the radius (R) of the corrugated cutting edge of the conventional roughing end mill is the same, and the waveform pitch (p) and the number of blade parts (N)'! r is a cutting action diagram (envelope) obtained by cutting with end mills having different values (cutting feed amount F is constant).

Table 1 shows the cutting cross section of each corrugated cutting edge in the cases shown in FIGS. 11 to 15.

As shown in Table 1 (opening force from Figures 11 to 15 above), the roughing end mill improves cutting by increasing the number of teeth (N) in the blade section and reducing the waveform pitch (P). The number of corrugated cutting edges involved can be increased, and the number of cutting edges per cutting edge can be increased. However, as mentioned above, with conventional end mills, the cutting cross section per tooth can only be divided in the axial direction of the end mill. However, it cannot be divided at all in the radial direction. For example, as the number (N) of the cutting edge (3) increases, the cutting cross section (Hl) of the wave-shaped cutting edge (5) in FIG. When the waveform pitch (P) is reduced, the cut section (H2) in Fig. 13 is obtained.Also, the blade section (3)
If the number (N) is increased and the waveform pitch (P) is reduced at the same time, the cut cross section (H4) shown in FIG. 15 is obtained, and both are subdivided only in the axial direction.

No matter how finely the cutting section is divided only in the axial direction, the specific cutting force only increases, and the cutting feed cannot be increased. For this reason, no particular effect on extending tool life or improving machining efficiency can be expected. In the above conventional products, in the radial direction (cutting feed direction) of the end mill, the cutting feed amount (F) per rotation of the end mill is the number of blades (N), the waveform pitch (Pl), and the waveform cutting edge - blade. Since it is the same as the cutting feed amount per hit, the cutting section cannot be divided in the radial direction.

Figure 16 (10 shows the blade part of a conventional roughing end mill (
The cutting life test results of roughing end mills with different number of teeth and waveform pitch (p) in 3) are shown. There is no significant difference in the cutting length when the surface wear is 0.251u.

(Means for solving the problem) This invention sequentially changes the position of the waveform blade of the peripheral blade to p for each peripheral blade.
By shifting the phase by xE''N (m=-1-), all 21 or more cutting blades having the same size and the same shape in the cross section perpendicular to the axis of the blade portion are provided, thereby solving the above problem.

(However, P: Pitch of the wave-shaped cutting edge, N: Number of blade parts having the wave-shaped cutting edge on the outer periphery of the tool body, m: Natural number, E:
1<E<N, and is a natural number having a common divisor other than 1 with N.

For example, if the number of peripheral teeth (N) is 4, E=2, so s
= z + 4 (m - t) and S = 2.6, 10°...
(Function) The end mill according to the present invention has twice the number of cutting edges of the waveform involved in cutting per revolution compared to conventional products, and the number of cutting edges of the waveform per revolution is twice as large as that of the conventional product. The cutting load on the cutting edge will be reduced to 100%, allowing for light cutting. In addition, even if the cutting feed amount is doubled from the above case, the cutting amount of the corrugated cutting edge is not different from that of the conventional product.

(Implementation ψ) Next, an embodiment of the present invention will be explained with reference to the drawings. Fig. 3 is a cross-sectional view taken at right angles to the axis from the line A-A" in Fig. 1, and shows a six-blade roughing end mill. The pitch (P) of the corrugated cutting edge is half that of the conventional product, that is, P'2F/2, where P is the pitch of the corrugated cutting edge and S=2. This is an enlarged view of the rake face side force/radial cutting edge (5) indicated by the arrow.The position of the wave-shaped cutting edge (5) of each cutting edge (3) is -moon of the cutting edge (5). The phase is shifted sequentially by pitch (p) Although the section is perpendicular to the axis, the radial dimension of each cutting blade on the D-D line is the virtual outer diameter, W (L
) is the same as &2 blade (It) and A5 blade (■ is virtual H
(L) It is located at the position where the upstream a is minus, and the ya 3 blade ([
10 and 6 blades (Vf is an imaginary line (D is located at the position minus D, La, b). Figure 5 shows this Rough Inogue/Domiru ti end mill - Cutting action line when cutting with cutting feed per revolution IIF Figure (envelope) is shown.

The 7'n part with hatching is the end mill axial length 2
End mill at F' - Cutting cross-sectional area per revolution (2P
'XF) is shown, but f'L has a cross-sectional area equal to the cutting cross-sectional area ( )/notching portion PXF ) per revolution of the conventional product shown in FIG. However, in this invention, the number of corrugated cutting edges (5) involved in cutting per rotation of the etmill is doubled in the radial direction. That is, in FIG. 11, the cutting cross-sectional area of the six blade pairs is divided not only in the axial direction but also in the radial direction.

Figure 6 shows the cutting action diagram (envelope 1) at 9 o'clock when the cutting feed amount F in Figure 5 is doubled, but the cutting cross-sectional area (H6) per stroke of the corrugated cutting edge is as shown in Figure 11. The area is equal to the cutting cross section fJ(H) per waveform cutting edge-to-edge of the conventional product shown in FIG.

In Figure 7, (S) = 2, the waveform pitch is (Pl2P/2)
Fig. 8 shows a cutting action diagram when cutting is performed with this end mill at twice the cutting feed rate (2F). The hatched part in each figure is
) shows the cutting cross section per rotation of the ethythm mill at K.

(Effects) As described above, the cutting edges are arranged so that two or more cutting edges having the same dimensions and the same shape appear on the exclusive plane perpendicular to the axis at any position of the blade portion. As a result, the cutting cross-sectional area is divided not only in the axial direction but also in the radial direction, and the depth of cut per corrugated cutting edge is half that of conventional products.
This reduces the amount of wear on the cutting edge and significantly improves the life of the cutting edge. In addition, even if the cutting feed rate is twice that of a conventional roughing end mill, the cutting load per corrugated blade is 17 to 18 when compared with the conventional cutting life test results shown in the same figure (A). It has doubled its lifespan.

[Brief explanation of the drawing]

Figure 1 is a side view of a normal roughing end mill, and Figure 2 is the force in the direction of the arrow in Figure 1. JAlso, a side view of a corrugated cutting blade, FIG. 3 is a sectional view of an embodiment of the present invention taken along line A-A' due to the first factor, FIG. 4 is a developed view of the cutting edge of the same embodiment, and FIG.
The figure is a cutting action diagram of the same embodiment, Fig. 6 is a cutting action diagram of the embodiment when the feed is doubled, Fig. 7 is a cutting action diagram of another embodiment, and Fig. 8 is a cutting action diagram of the embodiment in which the feed rate is doubled. Fig. 9 is a cutting action diagram of another embodiment, Fig. 9 is a production line diagram of the conventional product taken from line A-A' in Fig. 1, and Fig. 16 is a cutting life test result diagram of this invention in comparison with the conventional product. It is. 1...Body 2...Groove 3...Blade part 5...Corrugated cutting edge θ...
Torsion Angle Agent Patent Attorney Kawauchi Riku Ni Deaf A' Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Notebook 8 Figure 11 Figure 12 Figure 13 Solid Figure 14 Figure 15 Figure 1 Lifespan Sj *Z;1! ：Iin transparent face width gloss 7ax
F Agony (q, Otsu General No. 16 Figure Proceedings? Ho Seisho (self-proposal) October 3, 1985 Commissioner of the Patent Office Kuro 1) Akihiro 1, Indication of the case 1985 Patent Application No. 177847 2, Invention Name of Roughing End Mill 3, Relationship with the case of the person making the amendment Patent Applicant name (519) Fujikoshi Co., Ltd. 4, Agent residence 25, World Trade Center Building, 2-4-1 Hamamatsucho, Minato-ku, Tokyo Article 7, Contents of the amendment (7, 1) Delete ``in the direction of the arrow in Figure 2, that is,'' in the 6th line of page 2 of the specification. (7,2) “The blade is N00” on page 2, line 17.
1 blade (I) #・ra No, 6J, “The blade is No.
Correct from 1st blade (I) to No. 6J I-ko. (7, 3) rD-D on page 8, lines 7 to 8
line, is corrected to rD-D' line j. (7, 4) '(S)=2, y in the 14th line of page 9 is corrected to r(S=2), j. (7, 5) On page 10, line 9, ``The amount of wear also decreases, and 1.'' is corrected to ``The amount of rg wear also decreases.'' (7, 6) Figure 1 of the drawings shall be amended as shown in the attached sheet.

Claims (1)

[Claims] A plurality of grooves having a predetermined helix angle are formed on the outer periphery of the main body,
In a roughing end mill equipped with a blade having a wave-shaped cutting edge along the groove, the waveform of the cutting edge was sequentially shifted in phase by Px [[E+N(m-1)]/N] for each blade. A roughing end mill characterized by: However, P: Pitch of wavy cutting edge m: Natural number N: Number of blade parts having wavy cutting edge on the outer periphery of the tool body E: 1<E<N and has a common divisor other than 1 with N. Natural number