JP2948962B2 - Milling 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 cutting tool such as a face mill and an end mill, and more particularly to a cutting tool in which a cutting tip is disposed on an inner peripheral side of a tip end portion of a tool body.

[0002]

2. Description of the Related Art As a cutting tool for performing a plane processing on a work material, for example, as disclosed in Japanese Patent Publication No. 3-5925, a disc-shaped A concave portion is formed to be depressed toward the other end in the axial direction, and a plurality of cutting edge chips are detachably mounted on the inner peripheral wall portion of the concave portion at appropriate intervals in the circumferential direction. Type face milling cutters are known. In this kind of inner peripheral face milling cutter, the tool body is rotated around the axis and a relative movement in the radial direction of the tool body is given between the tool body and the work material. The cutting edge of the blade tip is cut into the work material, and the work material is flattened.

[0003]

In the above-mentioned conventional inner peripheral face type face milling cutter, since the cutting edge tip is provided on the inner peripheral wall of the recess of the tool body, the rake face of the cutting edge tip is provided. Chips that grow along the gap are confined in the recesses, and there is a disadvantage that the cutting edge is easily lost or the machined surface is easily damaged due to the bite of the chips. The present invention has been made under such a background, and an object of the present invention is to provide a milling tool that has good chip dischargeability and is less likely to cause defects such as cutting edge defects and machining surface damage.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a milling tool according to the present invention is provided at one axial end of a tool body.
A recess is formed that is depressed toward the other axial end of the tool body.
The cutting edge tip is attached to the inner peripheral wall of this recess,
The tool body in front of the rake face of the cutting edge tip on the inner peripheral wall
Chip pockets that are depressed toward the outer peripheral surface of the
In a milling tool, the outer peripheral surface and inner peripheral wall
A communicating chip discharge hole is formed, and one of the chip discharge holes is formed.
Make sure that the opening is located in the tip pocket on the inner peripheral wall.
Features. In addition, the milling tool mentioned here includes not only a face milling machine but also any cutting tool such as an end mill or a side milling machine which is configured to perform a cutting process by rotating a tool body around its axis. The milling tool of the present invention
To the center from both ends of the wall
It may be formed on a curved surface that is depressed as large as possible.

[0005]

[0006]

In the case of the milling tool of the present invention, the rotation of the tool body
The cutting edge of the cutting edge provided on the inner peripheral wall
The generated chips are placed on the rake face of the cutting insert.
Guided along the tip pocket along the curl and breaking
Etc. to the chip discharge hole as it is in the chip pocket
Chip discharge by the centrifugal force accompanying the rotation of the tool body guided
The inside of the hole is moved to the outer peripheral surface side and discharged from the outer peripheral surface to the outside.
It is. And along the curved shape of the tip pocket wall
Chips rolled out and fall out of tip pocket
The chip is guided to the chip discharge hole without any
It is made easier.

[0007]

[0008]

An embodiment of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 3, an inner peripheral type face milling machine 1 according to the present embodiment includes a disk-shaped tool body 2 made of a metal material such as tool steel. A tip mounting hole (concave) 3 which is cylindrically depressed from the tip end surface 2a of the tool main body 2 is formed so that its axis coincides with the axis X of the tool main body 2, and the inner peripheral wall portion 4 of the tip mounting hole 3 is formed.
The surface 4a of the inner peripheral wall portion 4 and the tip surface 2 of the tool body 2
are formed at regular intervals in the circumferential direction, and a cutting edge chip 6 is formed in these chip mounting grooves 5 by forming a hard material such as a cemented carbide into a square plate shape. ..., each rake face 6a is oriented in the direction of rotation of the tool body 2 (the direction of the arrow A1 in FIG. 2), and the main cutting edge 7 and the sub cutting edge 8 are respectively arranged on the surface 4a of the inner peripheral wall portion 4 and the tool body. The cutting edge tips 6 are arranged so as to slightly protrude from the distal end surface 2a of the second tip 2 and are firmly fixed in the tip mounting groove 5 by the clamp mechanism 10 so as to be roughly configured.

The clamp mechanism 10 includes a supporter 11 provided with a concave portion 11a for accommodating the cutting blade tip 6 on the upper surface side,
A wedge member 12 having a pair of wall surfaces 12a and 12b gradually approaching from the upper end side to the lower end side, and a male screw portion 13a is formed on one end side, and the opposite end is twisted in the opposite direction to the male screw portion 13a on the other end side. A male screw portion 13a of the clamp screw 13 is screwed into a screw hole 14 of the tool body 2 and a reverse screw portion 13b is screwed into the wedge member 12. The wedge member 12 is screwed into the hole 12c and the lower end side thereof (the wall surfaces 12a, 12b).
Of the tool body 2 is directed toward the radially outer peripheral side of the tool body 2, while the supporter 11 is held at its lower surface 11b.
And the side surfaces 11c and 11d are seated on the seating surface 5a of the chip mounting groove 5.
And fixed to the wall surfaces 5b and 5c with the bolts 10a while being in contact with the wall surfaces 5b and 5c.
The wedge member 1 is rotated by rotating the clamp screw 13 so that the male screw portion 13a moves to the outer peripheral side of the tool body 2.
2 is drawn toward the wall surface 5b side of the chip mounting groove 5, whereby the wall surfaces 12a and 12b of the wedge member 12 are brought into firm contact with the rake face 6a of the cutting blade tip 6 and the wedge support surface 5d of the chip mounting groove 5 so that the cutting blade Insert the tip 6 into the seating surface 5a of the tip mounting groove 5.
It is designed to press against the side.

Here, the male screw portion 13 of the clamp screw 13
The screw hole 14 of the tool body 2 screwed with the a is opened in the outer peripheral surface 2b of the tool body 2, and the end face side of the male screw portion 13a of the clamp screw 13 has a wrench hole 1 having a polygonal cross section.
3c is formed. This means that a work wrench (not shown) for rotating the clamp screw 13 is fitted to the clamp screw 13 from the outer peripheral side of the tool main body 2 so that the clamp screw 13 can be operated from the outer peripheral side of the tool main body 2, This is to facilitate the clamping operation.

The inner peripheral wall 4 of the tip mounting hole 3 is formed with a tip pocket 15 which is located in front of the rake face 6 a of the cutting edge tip 6 and which is depressed toward the outer periphery of the tool body 2.
These tip pockets 15 are provided to promote cutting by rolling chips extending along the rake face 6a of the cutting edge tip 6, and each wall face 15a is viewed from the tip end face 2a side of the tool main body 2. It is formed in a curved surface which is depressed in an arc shape toward the outer peripheral side of the tool body 2. here,
The upper surface 12d of the wedge member 12 is also formed into a curved surface and forms a part of the wall surface 15a of the chip pocket 15. The wall surfaces 15a of these chip pockets 15 constitute a part of the surface 4a of the inner peripheral wall portion 4 of the chip mounting hole 3 in this embodiment.

Further, the tool main body 2 includes
Are formed in the same number as the number of the cutting edge chips 6. Ends of the chip discharge holes 16 on the outer peripheral side are opened to the outer peripheral surface 2b of the tool body 2, while ends of the chip discharge holes 16 on the inner peripheral side are particularly wedges of the wall surface 15a of the chip pocket 15. Upper surface 12 of member 12
An opening is provided at a portion closer to the rear end side in the axial direction of the tool main body 2 than d. In FIGS. 1 and 2, reference numeral 17 denotes a bolt hole for connecting the tool body 2 to an arbor (not shown), and reference numeral 18 denotes a boss surface which is in close contact with an end surface of the arbor.

Next, the operation of the face mill configured as described above will be described with reference to FIGS. FIGS. 4 and 5 show a work W by the face mill 1 of the present embodiment.
This shows a state in which the flange F is machined around the boss B. The tool main body 2 is rotated around its axis X while the tool main body 2 is rotated about its rotation center P _{0 in} a plan view from the axis X direction. Is moved relative to the work material W so as to draw an arc trajectory C ₁ having a diameter L ₁ around the center P ₁ of the boss B of the work material W. And minor cutting edge 8
Is moved along the outer periphery of the boss B to process a desired flange F. The arc C ₂ in FIG.
3 shows the rotation locus of the main cutting edge 7 about the axis X of FIG.

In the above-described cutting process, chips growing along the rake face 6a of the cutting edge chip 6 are guided to the upper surface 12d of the wedge member 12 constituting the wall surface 15a of the tip pocket 15, and are curved by the curvature of the upper surface 12d. It is rounded after imitation. Subsequently, the chips rounded at an appropriate curvature are pressed against the wall surface 15a by the centrifugal force caused by the rotation of the tool body 2 while being newly generated by the cutting edges 7 and 8 at the rear end of the tool body 2. And is guided to the open end of the chip discharge hole 16. The chips guided to the chip discharge holes 16 move inside the chip discharge holes 16 to the radially outer peripheral side of the tool body 2 due to centrifugal force caused by the rotation of the tool body 2, and further, the outer periphery of the tool bodies of the chip discharge holes 16. The tool body 2 from the open end on the surface 2b side
Is discharged radially outward.

As described above, according to the face milling machine 1 of this embodiment, the chips generated by the cutting blades 7 and 8
The tool is discharged radially outward of the tool body 2 through the chip discharge hole 16 without being enclosed in the inside of the workpiece, so that defects such as chipping of the cutting blades 7 and 8 and damage to the machined surface due to biting of the chip occur. As a result, the tool life and the quality of the machined surface are improved. In this embodiment, in particular, each cutting tip 6
And the same number of chip discharge holes 16 as
a, the chips generated by the cutting blades 7, 8 are inserted into the chip mounting holes 3.
Since the chips are confined in the chip pocket 15 and guided into the chip discharge holes 16 without being scattered inside, the chips are quickly and reliably discharged from the chip discharge holes 16. Since the chip is rounded before reaching the chip discharge hole 16 by making the wall surface 15a of the chip pocket 15 a curved surface, the resistance when the chip passes through the chip discharge hole 16 is small, and the discharge of the chip is further enhanced. Made easy.

The wall surface 15a of the chip pocket 15
Needless to say, depending on the material of the work material, it is not necessary to form a curved surface. Also, the number of the chip discharge holes 16 does not necessarily have to be the same as the number of the chip inserts 6. For example, when the cutting volume is small, one chip discharge hole 1 is provided for every several chip inserts 6.
6 may be provided. Further, in this embodiment, a throw-away type front milling cutter to which a plurality of cutting edge tips 6 are detachably attached is taken as an example. However, a single-edge type milling tool or a brazing method in which a cutting edge tip is brazed. Naturally, the present invention can also be applied to a solid-type milling tool or a solid-type milling tool in which a cutting edge tip is integrally formed with a tool body.

Here, as shown in FIGS. 4 and 5, when a flange F is formed around the boss B by an inner peripheral face type face mill, the outer peripheral side of the tool body provided with a cutting edge tip is provided. There is a possibility that the time required for the cutting work can be shortened as compared with the case where the same shape is machined by the blade type face milling machine. As shown in FIGS. 4 and 5, when the flange F is formed by the inner peripheral face type face mill 1, the diameter of the minimum circumscribed circle C of the flange F is d ₀ , and the rotation locus about the rotation center P ₀ of the main cutting blade 7. Assuming that the diameter of C ₂ is D ₁ and the inner diameter of the flange F is d, the center of rotation P ₀ of the tool body 2 at the time of cutting is the circumference L of the rotation trajectory C ₁ drawn around the boss center P ₁ of the workpiece W. ₁ is given by L ₁ = π · (D ₁ −d) (a). Incidentally, the turning diameter D ₁ of the main cutting edge 7 is set according to the number of blades in the range greater than d _0.

On the other hand, as shown in FIG. 6 and FIG. 7, when the flange F is machined by the outer peripheral face type face mill 21 having the outer peripheral side of the tool main body 20 and the outer peripheral side, the main part of the If the diameter of the rotation trajectory C ₃ drawn around the rotation center P ₀ of the tool body 20 by the cutting blade 7 is D ₂ , the rotation center P ₀ of the tool body 20 is equal to the boss center P ₁ of the workpiece W during cutting. The circumference L ₂ of the rotation locus C ₄ drawn around is L ₂ = π · (D ₂ + d) (b). Incidentally, D ₂ are determined according to the number of cutting edge tip 6.

Thus, from the above equations (a) and (b), L ₁ ≤L _{2 in} the range of D ₁ ≤D ₂ + 2d (c). That is, the above equation (c)
If the range is satisfied, the above-described embodiment using the inner peripheral face type face mill 1 requires less movement of the milling cutter relative to the workpiece W, and as a result, the time required for the cutting work is reduced.

[0020]

As described above, according to the milling tool according to the present invention , the outer peripheral surface and the inner peripheral wall of the tool main body communicate with each other.
A chip discharge hole is formed, and one of the chip discharge holes is opened.
Since the mouth is located in the tip pocket on the inner peripheral wall,
Debris is guided from the rake face of the cutting edge into the tip pocket.
Chip discharge without falling off the chip pocket
It can be discharged to the outside of the tool body through the hole,
Chip accumulation in the recess without sacrificing the strength of the tool body
To prevent chips from being caught due to debris and scattering
Excellent ability to suppress defects such as damage and damage to the machined surface
The effect is obtained.

[Brief description of the drawings]

FIG. 1 is an axial sectional view of a face mill according to an embodiment of the present invention.

FIG. 2 is a bottom view of the front milling machine shown in FIG.

FIG. 3 is a view as seen from the direction of arrow III in FIG. 1;

FIG. 4 is a plan view showing an example of plane processing using the face mill shown in FIGS. 1 to 3;

5 is a view of the processing example shown in FIG. 4 as viewed from the radial direction of the face mill.

FIG. 6 is a plan view showing an example of plane machining using an outer peripheral type face milling machine.

7 is a view of the processing example shown in FIG. 6 as viewed from the radial direction of the face milling machine.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 inner peripheral face type face milling tool 2 tool body 2b outer peripheral surface of tool body 3 chip mounting hole (recess) 4 inner peripheral wall 4a surface of inner peripheral wall 6 cutting edge chip 6a rake face of cutting edge tip 15 tip pocket 15a tip Pocket wall 16 Chip discharge hole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 55-98516 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23C 5/06 B23C 9/00 B23Q 11 / 02

Claims (1)

(57) [Claims] A recess is formed at one end of the tool body in the axial direction to be depressed toward the other end of the tool body in the axial direction, and a cutting edge tip is attached to an inner peripheral wall of the recess.
Of the tool body in front of the rake face of the cutting edge tip
Milling with chip pockets that sink into the surface
A cutting tool for communicating the outer peripheral surface of the tool body with the inner peripheral wall portion.
A chip discharge hole is formed, and one opening of the chip discharge hole is
A milling tool characterized by being located in a chip pocket on an inner peripheral wall .