JP3391850B2 - 1-flute end mill - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-flute end mill used for machine tools such as a milling machine or a machining center, and is a one-flute end mill mainly used for cutting low melting point and low hardness materials such as aluminum or aluminum alloy. Regarding

[0002]

2. Description of the Related Art End mills conventionally used for cutting low melting point and low hardness materials such as aluminum or aluminum alloy are
By setting a large rake angle and chip pocket, it improves sharpness, suppresses welding, and improves machinability.By increasing the number of blades to 1, the chip pocket is further widened and clogging of chips. It was also possible to prevent cutting, such as plunging. (As an example, Jikken 62-36571)

However, in the conventional single-blade end mill, the rigidity of the tool body is insufficient because the chip pocket is widened and the chip disposal is prioritized, and even a slight change in the cutting resistance is likely to cause breakage. . Therefore, in order to improve the rigidity, it has been devised that the blade groove is tapered and the inscribed circle (hereinafter referred to as the core thickness) in a cross section perpendicular to the tool axis is gradually increased from the tool end portion toward the shank portion. (As an example, Shokai Sho 58-80120)

[0004]

However, in the current machining method, if the blade groove is tapered, the rake angle becomes smaller as the core thickness becomes larger, and the chip pocket becomes narrower, resulting in sharpness and chipping. There was a problem with the dischargeability.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and provides a one-flute end mill having rigidity and excellent sharpness and chip discharge.

[0006]

In order to achieve the above object, the present invention provides a one-flute end mill having a twisted cutting edge on the outer periphery of a tool body, from a tool end portion to a shank portion. One-flute end mill characterized by increasing the core thickness toward the end, making the arcuate shape R1 of the rake face in a cross section perpendicular to the blade part axis constant, and gradually increasing the arcuate shape R2 of the back part of the outer peripheral cutting edge. Is.

The above-mentioned shape can be obtained by a special processing method, and further sharpness is obtained by the synergistic effect of setting the twist angle of the outer peripheral cutting edge in the range of 25 ° to 50 °. It is a technical measure to secure it. . Here, it is possible to obtain a shape by applying an injection molding method as the processing method. further,
Needless to say, coating a hard film such as TiN, TiCN, TiAlN or diamond improves the welding resistance and the tool life. Further, if the cutting edge portion is formed of a diamond sintered body and fixed by a method such as brazing, the performance can be further improved.

[0008]

By applying the present invention, the core thickness can be increased from the tool end portion to the shank portion without changing the shape on the rake face side, and the tool rigidity and sharpness, and chip discharge performance can be improved. Was good. As a result, when cutting low melting point and low hardness materials such as aluminum or aluminum alloy, stable cutting can be performed without causing welding, chip clogging, breakage, etc. .

[0009]

1 to 4 show an embodiment of the present invention in which a tool blade die 10 mm, a tool end portion toward a shank portion,
Without changing the arc shape R1 of the rake face in the cross section perpendicular to the blade axis, only the arc shape R2 of the back of the cutting blade is gradually increased, and the twist angle of the outer peripheral cutting edge is set to 30 °. It is a single-flute end mill.

FIG. 9 shows the results of a comparative test between the present invention product and the conventional single-blade end mills shown in FIGS. Aluminum alloy is used as the work material, cutting speed 100 m / min Depth of cut 1
A groove of 0 mm was cut, and a limit test of one blade feed was performed for evaluation. Conventional product is 1 blade feed 0.15-0.2 mm /
While the number of blades was the limit, the product of the present invention was one blade feed 0.2
High feed of 5 to 0.3 mm / blade was possible, and vibration and chatter were also small at the same time.

[0012]

As described above, according to the present invention, it is possible to obtain a one-flute end mill which is rigid and has excellent sharpness and chip discharge property.

[Brief description of drawings]

FIG. 1 is a front view of one embodiment of the present invention.

FIG. 2 is a sectional view taken along the line A-A ′ of FIG.

FIG. 3 is a sectional view taken along the line B-B ′ of FIG.

FIG. 4 is a sectional view taken along the line C-C ′ of FIG.

FIG. 5 is a front view of an example of a conventional product.

6 is a cross-sectional view taken along the line D-D ′ of FIG.

7 is a sectional view taken along the line E-E ′ of FIG.

FIG. 8 is a sectional view taken along the line F-F ′ of FIG.

FIG. 9 is an explanatory diagram showing a comparison between the product of the present invention and the conventional product.

[Explanation of symbols]

1 body 2 cutting edges 3 end part 4 Shank part 5 core thickness R1 rake face arc shape R2 back arc shape θ twist angle

Claims (2)

(57) [Claims] 1. A single-flute end mill having a twisted cutting edge on the outer periphery of a tool body, wherein the core thickness increases from the tool end portion toward the shank portion, and the rake face in a cross section perpendicular to the blade axis. The single-edged end mill is characterized in that the circular arc shape R1 is constant and the circular arc shape R2 of the back of the outer peripheral cutting blade is gradually increased. 2. The single-flute end mill according to claim 1, wherein the helix angle of the outer peripheral cutting edge is set in the range of 25 ° to 50 °.