JP3264540B2 - Rotary cutting tool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary cutting tool in which a chip having a circular flat surface is rotatably mounted, and more specifically, a cutting load applied to a cutting edge of the chip during cutting. The present invention relates to a face mill and a rotary cutting tool suitable for turning and boring, in which a tip is rotated around an axis center for cutting by being added.

[0002]

2. Description of the Related Art Conventionally, in a rotary cutting tool such as a face mill, since a chip is used for a long time,
A chip has been developed in which a chip having a circular flat surface is rotatably mounted, and the chip is rotated during cutting so that the cutting edge of the chip is uniformly worn.

[0003] As such a rotary cutting tool, for example, a disk-shaped blade is rotatably mounted on a blade mounting shaft by a mounting bolt, such as a face milling machine disclosed in Japanese Patent Publication No. 58-30090. A rotor is inserted into a stator spindle via a ball bearing, a needle bearing and a thrust bearing, as in a rotary cutting tool disclosed in Japanese Patent Publication No. 64-3604, and a rotary cutting blade is attached to the rotor with a nut. And a rotary cutting blade is rotated together with the rotor by a load at the time of cutting.

However, in the above-mentioned Japanese Patent Publication No. 58-30090, the disk-shaped blade is rotatably fixed by the mounting bolts as described above. There is a danger that the above-mentioned mounting bolts will loosen and rattle on the disk-shaped blade, causing the disk-shaped blade to be broken. They may be arrested and lose their intended purpose.

[0005] In addition, the above-mentioned Japanese Patent Publication No. 64-3604 requires a thrust bearing, a needle bearing, a ball bearing, and the like. When attaching the blade to the tool body, the end of the stator and the end of the spindle are fitted and fixed in the recesses provided in the tool body, so the rigidity of the rotary cutting tool is reduced and cutting performance is reduced. May be deteriorated.

[0006] Moreover, the conventional rotary cutting tool is
Since a normal bearing system is used as a means for holding the rotating shaft, the structure is complicated and costs are high, and because of structural limitations, the tool becomes large, and cutting of the outer circumference, flat surface and curved surface with a large radius of curvature is performed. There is also a problem that only processing can be performed.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem in a rotary cutting tool, and a chip having a circular plane is smoothly rotated. The objective is to improve the cutting performance and wear resistance of the insert, reduce the number of parts and keep costs low, and increase the rigidity of this rotary cutting tool to greatly improve the accuracy of the work surface. It is.

[0008]

SUMMARY OF THE INVENTION In the rotary cutting tool according to the present invention, in order to solve the above problems,
A holder 2 for rotatably holding a circular chip 3 in a pocket 11 provided on the outer peripheral side of the tool body 1, an adjusting tool 4 for adjusting the deflection of the holder 2, and fixing the holder 2 In a rotary cutting tool provided with a tightening tool 5 to be tightened and a fixing tool 6 for preventing the tip 3 from jumping out, the tapered hole 21 is provided in the holder 2 while the tapered hole 21 is formed in the tip 3. A corresponding tapered shaft portion 32 is provided, and the tapered hole 21 in the holder 2 is provided.
A predetermined number of balls 8 are filled between the chip 3 and the tapered shaft portion 32 of the chip 3, and the chip 3 is rotatably held by the holder 2.

[0009]

In the rotary cutting tool according to the present invention, the tip 3 having the tapered shaft portion 32 is rotatably mounted on the holder 2 as described above.
During cutting, a vertical cutting force is applied to the cutting edge of the tip 3 so that the tip 3 is automatically held firmly in the tapered hole 21 of the holder 2, and a conventional rotary cutting tool is used. Thus, the need for a radial and thrust bearing system is eliminated. Therefore, the structure of the rotary cutting tool can be reduced in size and simplified, and the rigidity of the rotary cutting tool and the rotation accuracy thereof can be increased.

In the rotary cutting tool according to the present invention, the holder 2 for holding the chip 3 by the adjusting tool 4 is provided.
Can be freely adjusted in the axial direction of the tool main body 1, an extremely small number of uneven cutting edges can be easily obtained, and a highly accurate finished surface can be obtained.

In the rotary cutting tool according to the present invention, a predetermined number of balls 8 are provided between the tapered shaft portion 32 provided in the tip 3 and the tapered hole 21 provided in the holder 2.
Therefore, even if a cutting load is applied to the above-described chip 3, rattling or displacement of the chip 3 is prevented, damage to the chip 3 is reduced, and the precision of the work surface is greatly improved.

Further, in the rotary cutting tool according to the present invention, a predetermined number of balls 8 are provided between the tapered shaft portion 32 provided on the tip 3 and the tapered hole 21 provided on the holder 4 as described above. Because of the interposition, the tip 3 rotates extremely smoothly during cutting, improving the cutting performance with the cutting edge, and the entire circumference of the circular cutting edge is effectively used for cutting, greatly reducing the wear of the cutting edge. Is done.

In the rotary cutting tool according to the present invention, the structure of the rotary cutting tool is reduced in size and simplified, so that a small-diameter hole, which has been difficult with a conventional rotary cutting tool, can be formed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotary cutting tool according to an embodiment of the present invention will be specifically described below with reference to the accompanying drawings.

In this embodiment, the rotary cutting tool is a face mill, and FIG. 1 is a front view of a cross section of a main part of the face mill of the embodiment, and FIG. 2 is a cross section of a main part. 1 is a bottom view, FIG. 3 is a view taken in the direction of the arrow A in FIG. 1, and FIG. 4 is an enlarged explanatory view of a main part of FIG.

Here, in the face milling machine of this embodiment, as shown in FIG. 1, a mounting hole 10 for mounting to a machine tool (not shown) is provided at the center of the milling body 1.
A predetermined number of pockets 11 are formed on the outer peripheral side of the milling body 1.

In the face milling machine, the pocket 11 is provided with a holder 2 for rotatably holding the chip 3 having a circular plane, and an adjusting tool for adjusting the deflection of the holder 2 above the holder. The adjusting tool 4 adjusts the amount by which the holder 2 projects in the axial direction of the milling body 1. Here, the holding tool 2 is adjusted by the adjusting tool 4.
In adjusting the amount by which the milling body 1 protrudes in the axial direction, the vertical wall 12 of the pocket 11 of the milling body 1 and the rear surface 42 of the adjusting tool 4 are configured so that a wedge effect can be obtained. By moving the adjusting tool 4 back and forth in the radial direction of the milling body 1, the amount by which the holder 2 projects in the axial direction of the milling body 1 is adjusted.

In the face milling machine of this embodiment, as shown in FIG. 2, a sphere 7 is provided at the center of the front surface (squee surface) 31 of the chip 3 in order to prevent the chip 3 from jumping forward. The fixing tool 6 having the wedge effect as in the case of the adjusting tool 4
Is in contact with Then, the fixing tool 6 is connected to the bolt 61
The chip 3 is pressed through the sphere 7 and the chip 3 can be rotated by the sphere 7 so as to be fixed. As shown in FIG. 3, an abutment 62 made of a material having high wear resistance, such as a cemented carbide, is bonded to the contact surface of the fixture 6 pressing the sphere 7 in order to minimize wear. I have.

When attaching the holder 2 to the milling body 1, as shown in FIG. 3, the fastening tool 5 abutting on the holder 2 is tightened by bolts 51, and the pocket 11 of the milling body 1 is tightened. The holder 2 is fixed inside.

As shown in FIGS. 3 and 4, the holder 2 is formed with a tapered hole 21 at a predetermined position on one end side and a shaft 32 of the chip 3. Is also formed in a tapered shape corresponding to the tapered hole 21 of the holder 2, and the tapered hole 2 in the holding portion 2 is formed.
1 and the tapered shaft portion 32 of the chip 3 have a predetermined interval corresponding to the diameter of the ball 8.

The tapered hole 21 in the holding portion 2
A required number of balls 8 are inserted into the gap between the tapered shaft portion 32 of the chip 3 and the tapered shaft portion 32.

In order to fit the required number of balls 8 between the tapered hole 21 and the tapered shaft portion 32 as described above, a jig prepared separately, for example, A jig having a gap corresponding to the interval between the tapered shaft portion 32 is used, a plurality of balls 8 are inserted into the gap in the jig, and a resin having high lubricity and high mechanical properties flows into the gap. After the resin is solidified, the ball 8 bonded by the resin is taken out of the jig, and the ball 8 bonded by the resin is removed from the tapered hole 21 in the holder 2 and the chip 3 in the chip 3. It is to be inserted between the tapered shaft portion 32. In joining the ball 8 with the resin as described above, the ball 8 may be joined using the tapered hole 21 in the holder 2.

In the above embodiment, the case where the rotary cutting tool according to the present invention is a face mill has been described. However, the rotary cutting tool according to the present invention may be used as a turning tool or a boring tool. It is also possible to use.

[0024]

According to the rotary cutting tool of the present invention, as described above, the holder for holding the chip can be firmly fixed in the pocket of the tool body by the fastening tool. The rigidity and its rotational accuracy are improved, and the cutting performance is greatly improved.In addition, the position of the holder that holds the chip can be freely adjusted in the axial direction of the tool body by the adjustment tool, and the cutting edge with extremely small irregularity It is easy to obtain and a highly accurate finished surface can be obtained.

Further, in the rotary cutting tool according to the present invention, a predetermined number of balls are loaded between the tapered shaft provided in the tip and the tapered hole provided in the holder, so that the above-mentioned tip has a high height. Even when a cutting load is applied, the rattling and movement of the chip are prevented, the damage to the chip is extremely reduced, and the precision of the work surface is greatly improved.

Further, in the rotary cutting tool according to the present invention, a plurality of balls are interposed between the tapered shaft provided on the tip and the tapered hole provided on the holder as described above, so In, the insert rotates extremely smoothly, greatly improving the cutting performance, reducing the wear of the cutting edge, extending the life of the tool, and using the entire circumference of the outer cutting edge for cutting. By doing so, the cutting blade can be used effectively.

The rotary cutting tool according to the present invention does not require a radial and thrust bearing system unlike the conventional rotary cutting tool, and the structure of the tool is reduced in size and simplified, so that the conventional rotary cutting tool is not used. The machining of small diameter holes, which was difficult with a conventional cutting tool, can now be performed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional front view of a main part of a face mill according to an embodiment of the present invention.

FIG. 2 is a bottom view of FIG.

FIG. 3 is a view as viewed in the direction of arrow A in FIG. 1;

FIG. 4 is an explanatory diagram showing an enlarged main part of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool main body (milling main body) 2 Holder 3 Tip 4 Adjusting tool 5 Fastening tool 6 Fixing tool 7 Sphere 8 Ball 11 Pocket 21 Taper hole 32 Shaft

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-111801 (JP, A) JP-A-48-105989 (JP, U) JP-B Showa 64-3604 (JP, B2) JP-B Showa 58- 30090 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) B23C 5 / 24,5 / 06 B23B 27/12

Claims (1)

(57) [Claims] 1. A pocket 1 provided on an outer peripheral side of a tool body 1.
1, a holder 2 for rotatably holding a chip 3 having a circular plane, an adjuster 4 for adjusting the deflection of the holder 2,
In a rotary cutting tool provided with a fastening tool 5 for fixing the holding tool 2 and a fixing tool 6 for preventing the tip 3 from jumping out, the above-mentioned holding tool 2 is provided with a tapered hole 21 while the above-mentioned tip 3 is provided with a tapered hole 21. A tapered shaft portion 32 corresponding to the tapered hole 21 is provided, and the tapered hole 21 in the holder 2 and the tapered shaft portion 3 in the tip 3 are provided.
2. A rotary cutting tool characterized in that a predetermined number of balls 8 are filled between the cutting tool 2 and the holder 3, and the holder 3 is rotatably held by the holder 2.