JP3183716B2 - Indexable 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 holder for milling, especially for small diameters, and a throw-away tip.
The present invention relates to a tool applied to plunging, traversing, spiral cutting, and the like.

[0002]

2. Description of the Related Art Conventionally, in order to manufacture a groove that does not reach the outer edge of a workpiece, a type in which a hole not so deep is formed, and then the feed direction is changed to cut in a direction perpendicular to the direction of the previous hole. Mainstream. These include, for example, grooves for receiving adjustment springs. Therefore, in the case of the above-mentioned cutting tool, a hole is first made by sitting on one end of the groove of the workpiece, and then cutting is performed toward the other end of the groove of the tool. Therefore, the cutting is repeated at right angles to the axis of the shank, and the cutting is repeated toward the starting point of the groove.

However, in the conventional tool, the axial feed (drilling depth) performed during the drilling operation is limited to several tenths of 1 mm. If not repeated, no grooves can be formed, and therefore considerable processing time is required.

[0004]

Problems to be Solved by the Invention Therefore, reduction of the processing time requires a great amount of time especially for vertical feed. To reduce this time, an end mill capable of simultaneous vertical and horizontal feed was examined. It has been reached. Simultaneous vertical / horizontal feed is a well-known cutting method in profiling such as a ball end mill, but it has hardly been used in a square end mill, particularly in groove cutting.

[0005]

The basic shape of the present invention is the same as that of the above-mentioned type. However, the arrangement and shape of the chips are examined so that the axial feed is performed at an angle, the production cost is low, and the supply is low. It is an object of the present invention to provide a throw-away end mill which can be easily and deeperly drilled and shortens the machining time.

[0006] Therefore, as shown in FIG.
At the tip of the shank, at the front end of the shank, its cutting edge extends in the axial and radial directions from the outer periphery of the shank, in the axial direction, substantially parallel to the center of rotation, and in the radial direction, at an angle of inclination of 2 to 15 degrees,
As it extends beyond the center of rotation, it is arranged to incline slightly behind the center of rotation. The second TA chip has a structure in which the second TA chip is displaced by 180 degrees from the first TA chip to the outer periphery, and has two blades to increase the cutting efficiency. It is also possible to increase the number of blades as the blade diameter increases.

[0007] In addition, by using a rhombus and / or a parallelogram for the throw-away tip, an inclination angle of 2 to 15 degrees is provided in the radial direction beyond its axis, and furthermore, its rotation center is changed. As it extends further beyond, it is arranged to incline slightly behind the center line of rotation. The reason why the inclination angle is set to 2 to 15 degrees is the same as the squash angle provided in the conventional end mill when the inclination angle is less than 2 degrees, and when the inclination angle exceeds 15 degrees, the distance to the rotation center becomes too long, so the above range is set. . As a result, when performing inclined cutting, the bottom blade is always cut on the work material to perform cutting at the same time,
The balance during cutting is improved, and vibration and chatter are reduced. In the case of only lateral feed, cutting can be performed in the same manner as usual.

As described above, in the indexable end mill of the present invention, since the cutting at the center of rotation is performed smoothly, a groove deeper than the conventional one can be formed in one step. That is, the groove is formed by the tool of the present invention by cutting while simultaneously feeding vertically and horizontally from one end of the required groove to the other end, and when reaching the other end, inverting the tool, similarly cutting and completely cutting the groove. After cutting to a certain depth, this is achieved by using only the lateral feed. Hereinafter, an embodiment will be described in detail.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments. The shank 1 has at its front end a tip seat 2 for accommodating a TA tip made of cemented carbide. The shape of the TA chip 3 is a rhombus. Each edge of the rhombus forms a cutting edge. The blades of the TA tip 2 are designated by reference numerals 4, 5, and 6. T
It is desirable to provide a chip pocket 7 extending in the axial direction on each blade of the A-tip 3. A central opening is formed in each of the TA chips 3 and fixed to the shank 1 with set screws 8.

A TA tip 3 is provided at the front end of the shank 1 and its effective blade extends radially from the periphery of the shank 1 toward its axis, and is inclined by 15 ° from its radially outer end to its radially inner end. I have. Further, in a portion overlapping the axis, a chamfering blade 5 is attached to a corner as shown in FIG. Tip seat 2
A second TA tip 9 at the front end of the shank in another tip seat that is offset 180 ° around the shank from
Are arranged in the same manner as the first TA. However, since the center of the shaft is not cut, the TA chip is slightly smaller and no chamfering blade is provided.

The working procedure is as follows. The cutting tool according to the present invention is simultaneously fed vertically and horizontally to carry out machining. If the desired cutting depth is larger than the axial cutting edge length of the first TA chip, Can be placed on the same radius as the first TA tip 2 and then shifted axially, placing the third TA tip with its effective blade parallel to the axis A of the shank,
It is performed by repeating vertical and horizontal feed several times.

The effect of performing vertical and horizontal simultaneous feed is as follows.
In addition to shortening the time, the cutting force is greatly changed as shown in FIG. FIG. 4 shows a cutting speed of 100 m / m
The results of cutting at a feed rate of 0.1 mm / blade, an inclination angle of 5 °, a cutting depth of 0 to 3 mm, and measuring the cutting resistance are shown. In addition, general cutting was performed at a cutting depth of 3 mm.
From Fig. 4, the feed component of cutting (component force acting in the feed direction)
Is the same, but the main component (the component acting at right angles to the feed direction of the holder) decreases, and the back component (the component acting in the axial direction of the holder) increases at almost the same ratio. You can see that.

That is, in the inclined cutting, the holder receives a large force in the axial direction, but this component force merely presses the holder against the arbor, and has little influence on the performance and dimensions. Furthermore, the decrease in the back force reduces the fall of the holder, suppresses the occurrence of vibration and chatter, and indicates that chipping and chipping of the cutting blade are less likely to occur.

[0014]

As described above, the indexable end mill according to the present invention has a rhombic and / or parallelogram T shape.
By using the A-tip, cutting efficiency is improved by performing simultaneous vertical and horizontal feeds.

[Brief description of the drawings]

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

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is an explanatory view of a throw-away tip of the present invention.

FIG. 4 is an explanatory diagram showing measurement results of cutting resistance.

[Explanation of symbols]

 Reference Signs List 1 shank 2 tip seat 3 TA tip (parent blade) 4 TA tip cutting edge (radial direction) 5 TA tip cutting edge (chamfering edge) 6 TA tip cutting edge (axial direction) 7 Chip pocket 8 Set screw 9 TA chip (child blade)

Claims (1)

(57) [Claims] 1. A first TA insert, wherein the cutting edge is a cutting edge provided on a rhombus and / or a parallelogram throw-away end mill having a shank having a cutting edge at a tip and an outer periphery. At the front end of the shank, the cutting edge extends in the axial and radial directions from the outer periphery of the shank, and is substantially parallel to the center of rotation in the axial direction, and is rotated at an inclination angle of 2 to 15 degrees in the radial direction. A chamfering blade was provided near the center and arranged so as to be inclined behind the rotation center line, and the second TA chip was arranged so that the second TA chip was shifted 180 degrees from the first TA chip to the outer periphery. A throwaway end mill characterized by the following.