JPH0691406A - Cutting tool - Google Patents

Abstract

PURPOSE:To transmit a torque from a turning movement central shaft securely and smoothly to a throwaway chip by using no key. CONSTITUTION:In a turning movement central shaft 3 for rotatably supporting a throwaway chip 5, a brim 3a is provided with which a rake face 5d not concerning cutting machining out of rake faces 5c and 5d of the throw away chip 5 comes in contact. On the rake faces 5c, and 5d of the throw away chip 5, plural recess parts and/or project parts are formed concentrically with a cutting edge 5d project parts and/or recess parts which regulate a mutual sliding movement in turning movement direction, being engaged with the recessed parts and/or project parts formed on the rake faces 5c and 5d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting tool used for cutting a work piece.

[0002]

2. Description of the Related Art Conventionally, as a cutting tool used for cutting a work piece, there is a so-called cutting tool in which a cutting edge portion is integrally provided on a tool body. Therefore, when the cutting edge portion was worn out, it was polished and reused.

On the other hand, in recent years, a cutting tool in which a throw-away tip is attached to a tip holder corresponding to a conventional tool body is used, and when the cutting edge of the throw-away tip is worn by cutting, it is made disposable without polishing. , Increasingly, a new throw-away tip is attached to the tip holder to perform cutting again.

As such a throw-away tip, a round one having a cutting edge provided on the outer peripheral edge of the rake face is used, and the throw-away tip is rotated by the cutting resistance between the throw-away tip and the work piece. A cutting tool for cutting has also been developed (for example, Japanese Patent Laid-Open No. 61-279402).

On the other hand, when cutting is performed while rotating the throw-away tip only by the cutting resistance between the round throw-away tip and the work piece, the material of the work piece, the cutting depth, etc. When the cutting force changes, the cutting force may change and the rotation of the throw-away tip may become unstable. Therefore, a cutting tool that forcedly turns the throw-away tip was also developed.

FIG. 11 shows an example of a cutting tool for forcibly controlling and turning the throw-away tip.
This cutting tool 51 has a tip holder 52, and a throw-away tip mounting space 52a and a gear train installation space 52b are formed at the tip end portion of this tip holder 52, and the tip ends are located in both spaces 52a and 52b. A rotation center shaft 53 is rotatably provided via a bearing 54.

A round throw-away tip 55 as shown in FIG. 12 is inserted from the upper end of the rotation center shaft 53, and a mounting hole 55 for the throw-away tip 55 is provided.
A key 56 is provided between the key groove 55b formed in a and the key groove formed in the rotation center shaft 53 so that the rotation center shaft 53 and the throw-away tip 55 rotate integrally. .

This throw-away tip 55 is shown in FIG.
As described above, the key groove 55b is formed in the mounting hole 55a as described above, and the cutting edges 55 are formed on the outer peripheral edge portions of the upper rake face 55c and the lower rake face 55d, respectively.
e, 55e are formed, and the chip breaker forming groove 55f is formed concentrically with the cutting edges 55e, 55e.

A spacer 57 is inserted from the upper end of the rotation center shaft 53, and a pressing plate 58 is attached to the spacer 57 to fasten a bolt 59 on the upper surface side of the chip holder 52. The pressing plate 58 is thereby fixed, and the upper end small diameter portion of the rotation center shaft 53 is supported by the shaft support hole 58a formed in the pressing plate 58.

On the other hand, the gear 6 is provided on the lower end side of the rotation center shaft 53.
1 is fixed by a nut member 62, and the gear 6
The gear 63 meshing with 1 is the shaft member 64 and the nut member 6
5, a gear 66 meshing with the gear 63 is fixed to a rotation shaft 67a of a motor 67, and the motor 67 is fixed to the tip holder 52 side by a bracket 68 and a screw 69, and is rotated. The rotational driving force of the motor 67 serving as a drive source is transmitted to the rotation center shaft 53 through the gear train (66, 63, 61) in a decelerated manner, and then the throw-away tip 55 is arbitrarily rotated through the key 56 and the key groove 55b. It is supposed to rotate in any direction and at any number of rotations.

[0011]

However, in such a conventional cutting tool 51, the rotational driving force from the motor 67, which is the rotational driving source, is applied to the gear train (66, 63, 6).
1), because the structure is such that it is transmitted to the throw-away tip 55 via the rotation center shaft 53, the key 56 and the key groove 55b, a crack may occur at the corner portion of the key groove 55b, and this crack develops. Throwaway tip 55 is damaged, and keyway 55b and key 56
If a gap is formed between the and the gap, rattling occurs at the time of rotation, and it is difficult to smoothly rotate the throw-away tip 55. Therefore, such a problem is solved. That was a challenge.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and eliminates any problems caused by transmitting a rotational driving force through a key and a key groove, and makes it possible to use a throw-away tip. It is an object of the present invention to provide a cutting tool capable of smoothly rotating in a rotating direction and an arbitrary number of rotations.

[0013]

SUMMARY OF THE INVENTION According to the present invention, a round throw-away tip having a cutting edge provided on the outer peripheral edge of a rake face and the throw-away tip are rotatably supported via a turning central shaft. And a turning drive source for the throw-away tip, and the turning drive force by the turning drive source is transmitted to the throw-away tip via the turning center shaft to continuously connect the throw-away tip. Or, in a cutting tool for cutting a workpiece while rotating discontinuously, a collar that makes the rake face of the throw-away tip abutting the rake face of the rake face of the throw-away tip that does not participate in the cutting process. With the provision, on the rake face of the throw-away tip, a plurality of concave portions and / or convex portions are formed concentrically with the cutting edge, on the contact surface with the rake face of the collar, It is characterized in that a convex portion and / or a concave portion that engages with the concave portion and / or the convex portion formed on the rake face and regulates mutual sliding in the rotation direction is formed. The structure of the invention relating to such a cutting tool serves as means for solving the above-mentioned conventional problems.

[0014]

In the cutting tool according to the present invention, the rake face of the throw-away tip, which is not involved in the cutting process, comes into contact with the rotation center shaft for rotatably supporting the throw-away tip. With a tsuba that makes it
On the rake face of the throw-away tip, a plurality of concave portions and / or convex portions are formed concentrically with the cutting edge,
A convex portion and / or a concave portion that engages with a concave portion and / or a convex portion formed on the rake surface on a contact surface of the flange with the rake surface to regulate mutual sliding in a rotating direction. Therefore, even if the keyway is not formed in the throw-away tip and the key is not inserted in the key way, the concave portion and / or the convex portion formed on the rake face of the throw-away tip and By engaging the convex portion and / or the concave portion formed on the flange of the moving center shaft, the rotation of the rotating center shaft is surely transmitted to the throw-away tip, and the throw-away tip has a key groove. The problems such as cracks originating from the keyway and rattling in the keyway are eliminated and the rotation of the rotation center axis is smoothly transmitted to the throw-away tip. Further, the rake face that does not contact the flange of the rotation center shaft, that is, the concave portion and / or the convex portion formed on the rake face that participates in the cutting work effectively function as a chip breaker for cutting chips. It will be.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of a cutting tool according to the present invention. The cutting tool 1 has a tip holder 2, and a tip of the tip holder 2 has a throw-away tip mounted thereon. A space 2a and a gear train installation space 2b are formed, and a rotation center shaft 3 whose tip ends are located in both spaces 2a, 2b is rotatably provided via a bearing 4.

From the upper end of the rotation center shaft 3, FIG.
The circular throw-away tip 5 as shown in FIG. 4 is inserted, and as shown in FIG. 4, it is brought into contact with the collar 3a provided in the middle of the rotation center shaft 3.

In this embodiment, the throw-away tip 5 has a round shape as shown in FIG.
A mounting hole 5a is formed in the center, and cutting edges 5 are formed on the outer peripheral edge portions of the upper rake face 5c and the lower rake face 5d, respectively.
e and 5e are provided, and chip breaker forming grooves 5f are formed concentrically with the cutting edges 5e and 5e on the upper rake face 5c and the lower rake face 5d as shown in FIG. In addition, a large number of convex portions 5g are formed in the chip breaker forming groove 5f concentrically with the cutting edges 5e, 5e. Further, in FIG. 2, the lower rake face 5d
Chip breaker forming groove 5f and convex portion 5g formed on
Is not shown.

Further, as shown in FIG. 4, the rotation center shaft 3 is provided with a collar 3a having a diameter substantially equal to or slightly smaller than the diameter of the throw-away tip 5 and at the same time, of the collar 3a. Among them, a large number of concave portions 3g that engage with the convex portions 5g formed on the lower rake surface 5d are concentrically formed on the contact surface with the lower rake surface 5d of the throw-away tip 5, By engaging a large number of convex portions 5g formed on the away tip 5 with a large number of concave portions 3g formed on the collar 3a of the rotation center shaft 3, the throw away tip 5 and the rotation center shaft 3 are separated from each other. Therefore, it is possible to prevent the sliding drive force from the rotation center shaft 3 to be surely and smoothly transmitted to the throw-away tip 5 by preventing mutual sliding in the rotation direction.

In this case, it is also necessary that the rake surfaces 5c and 5d of the throw-away tip 5 and the contact surface between the rake surface 5d of the rotation center shaft 3 and the rake surface 5d are symmetrical with each other. Desirable depending on.

Furthermore, a spacer 7 is inserted from the upper end of the rotation center shaft 3, and a pressing plate 8 is attached to this spacer 7, and a bolt 9 is provided on the upper surface side of the chip holder 2. The pressing plate 8 is fixed by tightening, and the upper end small diameter portion 3b of the rotation center shaft 3 is supported by the shaft support hole 8a formed in the pressing plate 8.

On the other hand, a gear 11 is fixed to a male screw portion 3c formed on the lower end side of the rotation center shaft 3 by a nut member 12, and a gear 13 meshing with this gear 11 is a shaft member 1.
4 and a nut member 15, and a gear 16 meshing with the gear 13 is a rotary shaft 17a of a motor 17.
The motor 17 is fixed to the tip holder 2 side by a bracket 18 and a screw 19,
The rotation driving force of the motor 17 serving as the rotation driving source is transmitted to the gear train (1
6, 13 and 11) is transmitted to the rotation center shaft 3 through deceleration, and then the throw-away tip 5 is engaged through engagement between the concave portion 3g formed on the collar 3a and the convex portion 5g formed on the rake face 5d. Is transmitted to the throw-away tip 5 in an arbitrary rotation direction and an arbitrary number of rotations.

Therefore, even if the conventional structure in which the keyway is formed in the throw-away tip and the key is inserted in this keyway portion is not adopted, the concave portion 3g formed in the collar 3a of the rotation center shaft 3 is adopted. By engaging the convex portion 5g formed on the lower rake face 5d of the throw-away tip 5 with certainty, the turning force of the rotation center shaft 3 can be reliably and smoothly transmitted to the throw-away tip 5. Therefore, the throw-away tip 5 is unlikely to be cracked, and rattling does not occur between the throw-away tip 5 and the rotation center shaft 3, and the throw-away tip 5 is continuously or The machining accuracy and surface roughness are improved by cutting the workpiece while rotating it discontinuously, and the life of the throw-away tip 5 is extended. Furthermore convex portion 5g formed on the upper rake surface 5c of the cutting insert 5 became as it can further improve the function as a chip breaker.

FIG. 5 shows a comparison of the range of cutting conditions in which the cutting tool 1 according to the present invention and the conventional cutting tool 51 can cut, and simply forms the chip breaker forming groove 55f. Compared with the case of using the conventional throw-away tip 55, the use of the throw-away tip 5 in which a large number of convex portions 5g are formed in the chip breaker forming groove 5f makes it possible to cut chips with a small number of cuts. Was confirmed.

FIGS. 6 and 7 show another example of the shape of the throw-away tip 5 used in the cutting tool 1 according to the present invention. The throw-away tip 5 has a round shape and a mounting hole at the center. 5a is formed, and cutting edges 5e and 5e are provided on the outer peripheral edge portions of the upper rake face 5c and the lower rake face 5d, respectively, and further, the upper rake face 5c and the lower rake face 5d have a structure shown in FIG. As also shown in FIG. 5, the chip breaker forming groove 5 is formed concentrically with the cutting edges 5e, 5e.
f is formed, and the chip breaker forming groove 5 is formed.
The f has a structure in which a large number of concave portions 5h are formed concentrically with the cutting edges 5e, 5e.

Therefore, as shown in FIG. 8, the contact surface of the pivot shaft 3 with the lower rake surface 5d of the flange 3a has a convex shape in which the concave portion 5h of the rake surface 5d is inverted. A large number of concentric portions 3h are formed, and a concave portion 5h is formed on the lower rake face 5d of the throw-away tip 5.
By engaging with the convex portion 3h formed on the flange 3a of the rotation center shaft 3, the rotation driving force of the rotation center shaft 3 is surely and smoothly transmitted to the throw-away tip 5. The case is shown.

FIG. 9 shows still another example of the shape of the throw-away tip 5 used in the cutting tool 1 according to the present invention, in which two tips are formed in the tip breaker forming groove 5f formed concentrically with the cutting edge 5e. It shows a case where a large number of continuous convex portions 5g, 5g are formed in a concentric circle as a set, and the rake face 5c, 5 is formed on the collar 3a of the rotation center shaft 3.
Two consecutive recesses (3
g, 3g) as a set to form a large number of concentric circles.

FIG. 10 shows still another example of the shape of the throw-away tip 5 used in the cutting tool 1 according to the present invention. One is provided in the tip breaker forming groove 5f formed concentrically with the cutting edge 5e. It shows a case where a large number of convex portions 5g and one concave portion 5h are formed concentrically, and the rake face 5 is formed on the collar 3a of the rotation center shaft 3.
One concave part (3g) with the shape reversed in c and 5d
And one convex portion (3h) are combined to form a large number of concentric circles.

[0028]

In the cutting tool according to the present invention, the rake face of the throw-away tip, which is not involved in the cutting process, comes into contact with the rotation center shaft for rotatably supporting the throw-away tip. With a tsuba that makes it
On the rake face of the throw-away tip, a plurality of concave portions and / or convex portions are formed concentrically with the cutting edge,
A convex portion and / or a concave portion that engages with a concave portion and / or a convex portion formed on the rake surface on a contact surface of the flange with the rake surface to regulate mutual sliding in a rotating direction. Therefore, even if the keyway is not formed in the throw-away tip and the key is not inserted in the key way, the concave portion and / or the convex portion formed on the rake face of the throw-away tip and By engaging the convex portion and / or the concave portion formed on the flange of the moving center shaft, the rotation of the rotating center shaft is surely transmitted to the throw-away tip, and the throw-away tip has a key groove. The problems such as cracks originating from the keyway and rattling in the keyway are eliminated and the rotation of the rotation center axis is smoothly transmitted to the throw-away tip. Further, the rake face that does not contact the flange of the rotation center shaft, that is, the concave portion and / or the convex portion formed on the rake face that participates in the cutting work effectively function as a chip breaker for cutting chips. Since the chips can be cut efficiently, and there is no need to form a key groove in the throw-away tip, it is possible to improve the strength of the throw-away tip and improve the durability of the throw-away tip. As a result, a remarkably excellent effect such as that it can be used even in cutting with impact such as intermittent cutting is brought about.

[Brief description of drawings]

FIG. 1 is a partially cutaway explanatory view showing a cutting tool according to an embodiment of the present invention.

FIG. 2 is an explanatory view of an inclined surface showing a shape example of a throw-away tip used in a cutting tool according to an embodiment of the present invention.

FIG. 3 is a partial vertical cross-sectional explanatory view of the throw-away tip shown in FIG.

FIG. 4 is an explanatory view of an inclined surface of a rotation center shaft used in the cutting tool according to the embodiment of the present invention.

FIG. 5 is a graph showing a range of cutting conditions in which chips can be cut between the cutting tool according to the present invention and a conventional cutting tool.

FIG. 6 is an explanatory view of a slope showing another example of the shape of the throw-away tip used in the cutting tool according to the embodiment of the present invention.

FIG. 7 is a partial vertical cross-sectional explanatory view of the throw-away tip shown in FIG.

FIG. 8 is an explanatory view of a slope of a rotation center shaft used with the throw-away tip shown in FIG.

FIG. 9 is an oblique surface explanatory diagram showing still another example of the shape of the throw-away tip used in the cutting tool according to the embodiment of the present invention.

FIG. 10 is a slope explanatory view showing still another example of the shape of the throw-away tip used in the cutting tool according to the embodiment of the present invention.

FIG. 11 is a partially broken explanatory view showing a conventional cutting tool.

FIG. 12 is an explanatory view of a slope of a throw-away tip used in a conventional cutting tool.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutting tool 2 Tip holder 3 Rotation center shaft 3a Rotation center shaft collar 3g Concave portion (convex portion and / or concave portion) 3h Convex portion (convex portion and / or concave portion) 5 Throw-away tip 5a Throw-away tip mounting hole 5c Upper rake face 5d Lower rake face 5e Cutting edge 5f Chip breaker forming groove 5g Convex portion (concave portion and / or convex portion) 5h Recessed portion (recessed portion and / or convex portion) 17 Motor (rotational drive source)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sadazaki Shiro Shiro, 2 Takaracho, Kanagawa-ku, Kanagawa Yokohama, Japan Nissan Motor Co., Ltd.

Claims (1)

[Claims] 1. A round throw-away tip provided with a cutting edge on an outer peripheral edge of a rake face, a tip holder for rotatably supporting the throw-away tip through a turning central shaft, and the throw-away tip. With a tip rotation drive source,
A cutting tool for cutting a work piece while transmitting the rotational drive force from the rotational drive source to the throw-away tip through the pivot shaft to rotate the throw-away tip continuously or discontinuously. In the rotation center axis, while providing a brim for abutting the rake face of the rake face of the throw-away tip that does not participate in the cutting process, the rake face of the throw-away tip, concentric circles with the cutting edge. A plurality of concave portions and / or convex portions are formed, and the contact surface of the flange with the rake surface is engaged with the concave portion and / or the convex portion formed on the rake surface to rotate. A cutting tool having a convex portion and / or a concave portion for restricting mutual sliding in the directions.