JPH11188509A - Cutting tools - Google Patents

Abstract

(57) [Problem] A cutting tool of a type in which a rear end portion of a tip is pressed and fixed to a tip seat portion recessed in a lateral side of a tip end of a holder with a holding plate, and a large tip fixing force is applied uniformly. Provided is a cutting tool characterized in that it can be quickly and firmly fixed, has high mechanical strength, and hardly generates chatter vibration. A through hole (7) provided in a holding plate (6) with a fixing screw (8).
Through the chip seat portion 4 of the holder 2 and the back surface 9 thereof.
Then, the holding plate 6 is pressed by a screw head 11 having a large diameter of the fixing screw 8. in addition,
The rear end surface 6a of the holding plate 6 and the inclined surface 2a of the holder 2 facing the rear end surface 6a are also formed in a tapered shape, and a mutual angle difference α ° = 1 ° to 5 ° is provided so that both of them come into contact with each other. At the same time, the center axis P1 of the through hole 7 provided in the holding plate 6 and the center axis of the screw hole 10 provided in the holder 2 are d =
Eccentrically by about 0.2 to 0.5 mm.

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 columnar work or forming a circumferential groove on the outer or inner periphery thereof.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. A cutting tool 30 of a type that is fixed to the tip seat portion 35 by pressure contact is used.

[0003] Since the cutting tool 30 is installed so that the back surface 36 side of the chip seat portion 35 is exposed from the machine, a fixing screw 37 is inserted from the back surface 36 and fixed to a screw hole 38 provided in the holding plate 33. By screwing the tip of the screw 37, the holding plate 33 is drawn toward the chip seat 35, and as a result, the holding plate 33
4 and is fixed to the tip seat portion 35 by pressure.

However, in the above-mentioned conventional cutting tool 30, since the holding plate 33 and the fixing screw 37 are engaged only in the screw groove fitting in the screw hole 38, the pulling force cannot be sufficiently increased. Further, since the force acts only on a very narrow area near the screw hole 38, the force for pressing and fixing the chip is transmitted unevenly to the part,
Is unstable, and when cutting under a high load, there are problems such as chatter vibration and damage of the chip 32 and the holder 34 due to the chatter vibration.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, the present invention provides a cutting machine of the type in which the rear end of a chip is pressed and fixed to a chip seat recessed in a lateral side of the front end of a holder by a holding plate. In a cutting tool, a cutting tool is characterized in that a chip fixing force is large, a force is uniformly applied to the chip, strong fixing can be quickly performed, mechanical strength is large, and chatter vibration is hardly generated. Make it an issue.

[0006]

In order to solve the above-mentioned problems in the prior art, a cutting tool according to the present invention is provided with a large-diameter cutting screw which is screwed from a tip seat portion toward a back side and provided at a rear end thereof. The holding plate is pressed from the outside with a screw head, and further, a fixing screw is inserted in a tapered shape with an angle difference so that the rear end surface of the holding plate and the inclined surface of the facing holder face each other. By eccentrically aligning the hole provided in the holding plate with the hole provided in the holder in the axial direction of the tool, the rear end face and the oblique cut face are gradually pressed from top to bottom in accordance with the screwing of the fixing screw. Then, as a reaction to the pressure contact, a force of the pressing plate for strongly pressing the chip toward the front lower side is applied, and as a result, the fixing force of the chip is increased, and the problem of chatter vibration is less likely to occur.

That is, according to the present invention, the rear end face of the holding plate and the inclined surface of the holder facing the rear end surface are tapered, and the rear end surface and the inclined surface are engaged with each other so as to engage with the upper end. An angle difference α = 1 to 5 ° is generated, and a fixing screw through-hole provided in the holding plate and a screw hole provided in the holder are arranged in the axial direction of the tool by 0.2 to 0.5.
mm, the rear end face and the inclined plane are gradually pressed from top to bottom in accordance with the screwing of the fixing screw when the fixing screw is screwed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of a cutting tool 1 according to the present embodiment. This cutting tool 1 has a tip seat portion 4 on a tip side surface 3 of a holder 2 made of hardened tool steel or carbide. A fixing screw 8 is inserted through a through hole 7 provided in the holding plate 6 so as to press-fix the cutting tip 5 to the tip seat portion 4 with a holding plate 6 by pressing.
The holding plate 6 is screwed into a screw hole 10 provided from the tip seat portion 4 to the back surface 9 thereof, and the holding plate 6 is pressed with a large-diameter screw head 11 of the fixing screw 8. It is designed to be fixed.

The tip seat 4 of the holder 2 has a bottom surface 12
Are provided horizontally, and β = 5 ° with respect to the vertical direction.
A taper restraining surface 13 having an inclination of up to 45 ° is formed, and this taper restraining surface 13 comes into contact with a corresponding taper restraining surface 14 of the chip 5.
Further, the holder 2 has a pin 24 protruding from the chip seat portion 4 and fitted into a concave hole 25 provided at a corresponding position of the chip 5 so that the cutting edge height and the cutting edge position of the chip 5 are accurately set. You can do it.

Next, the tip 5 has a strip-shaped cutting edge 15 on the front side, a cutting edge 16 provided on the upper edge of the cutting edge, and a fixed portion 17 having the tapered restraint surface 14 on the rear side. A stepped pressing portion 18 is provided on the rear end side to engage with the pressing plate 6.

The holding plate 6 is provided with a tapered surface 19 at the opening of the through hole 7, and the large diameter screw head 11 provided at the rear end of the fixing screw 8 is provided with the tapered surface 19.
Is pressed.

FIG. 2 is a perspective view showing the back surface 9 of the cutting tool 1. As shown in FIG. 2, a tip end of a hexagon wrench 21 and a driver (not shown) A turning groove 22 is provided for engaging with the tip of the fixing screw 8.
An external screw and an internal screw of the screw hole 10 of the holder 2 are formed on the fixing screw 8 so that the screw becomes a right-handed screw or a left-handed screw when rotating. The rotation of the fixing screw 8 can be performed by a right-handed screw or a left-handed screw.

The right-handed screw or the left-handed screw may be arbitrarily selected. Although the cutting tool 1 of the present embodiment is of the back-constrained type as described above, it is not necessary to limit the present invention to the back-constrained cutting tool. However, as an advantage of using the back-constrained type as in the above-described cutting tool 1, since the rotation of the fixing screw 8 can be performed from the back 9 side of the chip seat portion 4, the holder 2
There is a point that the chip 5 can be replaced without removing the chip 5 from a machine tool (not shown).

FIG. 3 is a front view showing a tip portion of the cutting tool 1, but for the sake of explanation, the fixing screw is not screwed. As shown in the drawing, the rear end face 6a of the holding plate 6 is formed in a tapered shape, and the inclined face 2a of the holder 2 facing the rear end face 6a is also formed in a tapered shape, and furthermore, both of them become upper hits. A mutual angle difference α ° = 1 ° to 5 ° was provided so that the distance between the two gradually increased toward the lower side. Further, the center axis P1 of the through hole 7 provided in the holding plate 6 and the screw hole 1 provided in the holder 2 are provided.
0 is eccentric about d = 0.2 to 0.5 mm, and when a fixing screw (not shown) is screwed in, the rear end face 6a of the holding plate 6 is screwed in according to the screwing of the fixing screw. The inclined face 2a of the holder 2 facing the workpiece is gradually pressed from top to bottom. As a result, when the fixing screw is screwed, a force F that the pressing plate 6 strongly pushes the chip 5 toward the front lower side acts as a reaction of the pressure contact between the rear end surface 6a and the inclined surface 2a, and as a result, The fixing force of the tip 5 is increased, and the problem of chatter vibration is less likely to occur. When the mutual angle difference α ° is less than 1 °, the force F of the pressing plate 6 for strongly pushing the chip 5 to the front lower side becomes insufficient, which may cause blurring or the like. If it is large, the strength of the chip 5 may be low. When the eccentric distance d between the through hole 7 and the screw hole 10 is less than 0.1 mm, the force F becomes insufficient, and there is a possibility that blurring or the like may occur. May be reduced in strength.

In the cutting tool 1 thus configured, as shown in FIG. 1, a large-diameter screw head 11 provided at the rear end of the fixing screw 8 presses the tapered seat turning surface 19. Large force can be transmitted to the holding plate 6, and the fixing screw 8 and the holding plate 6 come into contact with a relatively large area. The chip 5 can be fixed.

In addition, as described above with reference to FIG. 1, the tip seat 4 of the holder 2 has β = 5 ° to 45 ° with respect to the vertical direction.
The chip 5 is prevented from rattling, chattering, and the like by increasing the restraining force by abutting engagement with the tapered restraining surface 13 having the inclination and the corresponding taper restraining surface 14 of the chip 5. As shown in the exploded perspective view of FIG. 4, the upper side of the pressing portion 18 of the chip 5 is notched horizontally, and the convex portion 23 is formed on the pressing plate 6 so as to correspond to the notched portion. In addition, rattling and chattering of the insert 5 can be suppressed, and the position and height of the cutting edge of the insert 5 can be accurately set.

The inclination angle β of the tapered constraint surface 13
Is less than 5 °, the effect of preventing rattling and chattering vibration may be reduced. On the other hand, when β exceeds 45 °, the strength of the chip 5 may be too small.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments, and it goes without saying that the present invention can take any form without departing from the object of the invention.

[0020]

As described above, according to the cutting tool of the present invention, the fixing screw is screwed from the tip seat portion toward the back side, and the holding screw is provided with a large-diameter screw head provided at the rear end. Since the plate is pressed from the outside, a large force can be transmitted to the holding plate, and furthermore, it is fixed in a tapered shape with an angle difference so that the rear end surface of the holding plate and the inclined surface of the holder facing each other have an upper contact. By displacing the hole provided in the holding plate for inserting the screw and the hole provided in the holder in the axial direction of the tool, the rear end face and the oblique cut face are gradually pressed from top to bottom according to the screwing in of the fixing screw. I will do it. Then, as a reaction of the pressing, a force of the pressing plate strongly pressing the chip toward the front lower side acts, and as a result, the fixing force of the chip is increased, and the problem of chatter vibration is less likely to occur.

As described above, the cutting tool of the present invention is very excellent in that it has a large tip fixing force, can be firmly fixed by being uniformly applied, can be quickly fixed, has high mechanical strength, and hardly generates chatter vibration. It has the effect that it has.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a cutting tool according to the present invention.

FIG. 2 is a perspective view showing a back surface of the cutting tool of FIG. 1;

FIG. 3 is a front view showing a tip portion of the cutting tool of FIG. 1;

FIG. 4 is an exploded perspective view of a cutting tool according to another embodiment of the present invention.

5 (a) is a plan view, FIG. 5 (b) is a top view, FIG. 5 (c) is a front view, and FIG. 5 (d) is a front view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutting tool 2 Holder 2a Beveled surface 3 Tip side surface 4 Tip seat part 5 Tip 6 Holding plate 6a Rear end surface 7 Through hole 8 Fixing screw 9 Back surface 10 Screw hole 11 Screw head 13, 14 Taper restraining surface 20 Tip surface 22 For rotation Groove α Mutual angle difference β Tilt d Eccentric distance

Claims (2)

[Claims] 1. A tip end provided with a cutting blade on a top surface of a tip is pressed and fixed to a tip seat portion recessed on a lateral side of a tip end of a holder by a pressing plate, and is fixed to the tip seat portion and a back surface thereof. A cutting tool that presses the holding plate with a screw head of a fixing screw that is screwed into a penetrating screw hole, wherein a rear end surface of the holding plate and a beveled surface of a holder facing the rear end surface have a tapered shape. None, and an angle difference α = 1 to 5 ° is generated between them so that the rear end surface and the obliquely cut surface are engaged with the upper contact, and a through hole for a fixing screw and a holder provided in the holding plate are provided. The provided screw hole is displaced by 0.2 to 0.5 mm in the axial direction of the tool, and when the fixing screw is screwed, the rear end face and the oblique cut face face downward from above according to the screwing of the fixing screw. Characterized in that it is configured to gradually press in Cutting tools. 2. The apparatus according to claim 1, wherein the tip of the holder is perpendicular to the tip seat.
2. The cutting tool according to claim 1, wherein a tapered constraint surface having an inclination of 5 to 45 [deg.] And a tapered constraint surface corresponding to the tapered constraint surface are formed on the tip.