JP2001038517A - Throwaway type side cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a discharge of chip and to certainly prevent a generation of burr by forming an outer side surface of throwaway tip to which a clearance angle is imparted to a trapezoid and attaching the tip to a tool body in the form of staggered tooth in which an upper surface of the trapezoid is made to a seating surface and a lower surface is made to a side surface. SOLUTION: A throwaway tip 7 is alternately attached to both end surface sides of a tool body in the form of staggered tooth in the state that a sharp angle corner 13 is projected to the outside in a width direction of the tool body. At this time, both upper and lower surfaces 8 are formed to a rectangular shape respectively and a clearance angle is previously imparted thereto. Both outer side surfaces 10, 11 are formed to a trapezoid respectively, this upper surface is made to a seating surface and a lower surface is made to a side surface. One outer side surface 10 is made to a face and the other outer side surface 11 is made to a flank. A cutting blade 14 having a long side in a groove depth direction is disposed on a side ridgeline portion at one outer side surface 10 and a cutting blade 15 having a short side in the groove depth direction is provided thereon. A corner R is formed on a sharp angle corner 13 at which these are crossed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away type side cutter in which a throw-away tip is incorporated on the outer periphery of a disk-shaped tool body, and is particularly suitable for cutting stainless steel and mild steel.

[0002]

2. Description of the Related Art FIGS. 8 and 9 show such a throwaway type side cutter disclosed in, for example, Japanese Utility Model Laid-Open No. 5-12027.

A tip 22 is mounted on a tip mounting seat 21 formed on an outer peripheral side surface of a tool body 20 made of a disk-shaped steel material or the like. The tip 22 is a square flat plate made of a cemented carbide or the like, and has a cutting edge formed at the intersection ridge line between the upper and lower surfaces and the outer surface. A mounting hole 24 for fixing the chip 22 to the chip mounting seat 22 is formed in the center of the upper and lower surfaces of the chip 22.

The chip mounting seat 2 on which the chip 22 is seated
1 is formed in a concave groove shape so that the upper and lower surfaces of the chip 22 can be mounted in the radial direction of the tool main body 20. A screw hole is screwed to match the hole 23.
Such tip mounting seats 21 are arranged in a staggered manner at equal intervals in the circumferential direction of the outer peripheral surface of the tool body 20.

[0005] The chip 22 is placed on the chip mounting seat 21, a tightening screw is inserted into the mounting hole, and the tightening screw is screwed into the screw hole of the chip mounting seat 21. It is directly fixed in a state where the thickness direction faces the radial direction of the tool body 20.

[0006]

Here, the problems of the prior art will be described below.

The prior art described above is an improvement of the chip arrangement and clamping method. That is, in order to improve the rigidity of the tool main body, the insert is arranged so that the thickness direction of the chip is made to coincide with the radial direction of the tool main body, and a fixing method using a tightening screw is adopted.

However, in the throw-away type side cutter having this configuration, the groove of the chip pocket is formed shallow to increase the rigidity of the tool body. Further, the gap between adjacent chips is narrow, and the groove width of the chip pocket provided in front of the chip in the rotation direction is inevitably narrow.

[0009] For this reason, in particular, when machining a material that discharges flow-type chips, such as mild steel or stainless steel, or when machining under a condition of a deep cut and a high feed rate, high efficiency. Insufficient discharge of chips caused chips to accumulate in the chip pockets, leading to an increase in cutting resistance, deformation of the tool body, and vibration.

Further, in the above-mentioned prior art, although the rake angle in the axial direction of the insert is inclined rearward in the rotational direction as the rake angle in the axial direction from the both end surfaces of the tool body to the center,
The angle was small, and the generation of burrs could not be completely prevented.

The present invention has been made in view of such a technical background, and an object of the present invention is to provide a throw-away type side cutter capable of improving chip evacuation and preventing the generation of burrs. Is what you do.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has a flat plate-shaped throw-away tip mounted on a tip mounting seat recessed on an outer peripheral side surface of a disk-shaped tool body. However, in a throwaway type side cutter whose outer surface is made to be detachably mounted as a rake surface, a clearance angle is given to the throwaway tip, and the outer surface is formed in an external trapezoidal shape. A pair of outer surfaces is a rake surface, and a corner R is formed at a trapezoidal acute angle corner of the outer surface, and the trapezoid has an upper base as a seating surface and a lower base as a side surface. The throw-away tip is mounted in a staggered blade format.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

First, FIGS. 1 to 6 show a first embodiment of the present invention. FIGS. 1 and 2 show a state in which a throw-away tip (hereinafter, referred to as a “tip”) 7 is mounted on a disk-shaped tool body 1. The tool main body 1 is formed of a steel material or the like, and has a mounting hole 2 at the center thereof for mounting to a spindle end of a machine tool. Chip mounting seats 3 are formed on the outer periphery of the tool body 1 at equal intervals in the circumferential direction, and a V-groove-shaped chip pocket 6 is formed in front of the tool rotation direction N in an end view. .

The chip mounting seat 3 is formed by cutting out a concave groove so that the lower surface 9 of the chip 7 can be mounted in the axial direction of the tool body 1. Is screwed. The chip 7 is directly connected to the tool body 1 by the tightening screw 5 through a mounting hole 12 penetrating through the center thereof.
Is screwed on. The reason why the chips 7 are arranged vertically is to process a narrow groove and to improve strength in the main component direction of the cutting resistance.

FIG. 3 is a view of the throw-away type side cutter viewed from the outer peripheral surface. The tips 7 are mounted alternately on both end faces of the tool body 1 in a so-called staggered blade form with the sharp corners 13 protruding outward in the width direction of the tool body 1. The staggered blade type is adopted because the cutting edge of the tip 7 is alternately involved in the inner wall of the groove, so that the tool body 1
This is for avoiding deformation and performing well-balanced processing.

The short side cutting edge 15 formed on the side ridge of the outer surface 10 of the tip 7 is inclined at a predetermined angle (hereinafter referred to as “axial rake”) α with respect to the axial direction of the tool body 1. It is arranged. The direction of the inclination is a direction of retreating backward in the rotation direction N from the end face side of the tool body 1 toward the center of the width (hereinafter, this direction is referred to as “positive”). This angle is set at 3 ° to 25 °. If the angle is smaller than 3 °, the effects of the present invention described later cannot be obtained. If the angle is larger than 25 °, the cutting edge strength decreases and the life becomes short.

The reason why the axial rake α is set to be positive is to firstly improve the biting property and prevent the generation of burrs due to sharp cutting. Secondly, it is for reducing cutting resistance and avoiding generation of vibration. Third, it is for controlling the chip outflow direction to obtain excellent accuracy of the inner wall surface of the groove. When the axial rake α is negative, that is, when it comes into contact with the center of the width of the tool body 1 and separates from the end side, the chip also flows from the center to the end side, so that the chip discharge property is good. There is a problem that chips may collide with and come into contact with the inner wall surface of the processing groove and damage the wall surface. On the other hand, when the axial rake α is positively formed as in the configuration of the present invention,
It comes into contact with the end side of the tool main body 1 and separates from the center of the width, and the chips flow in the same manner, so that it is possible to prevent the inner wall surface of the groove from being damaged. On the other hand, however, another problem that the chip discharge performance is reduced and the chip is clogged occurs. Therefore, the present invention sets the angle of the axial rake α to be sufficiently large,
The chip pocket 6 is made deeper and formed in a V-groove shape on the outside of the tool body 1 in the radial direction to prevent chip clogging and prevent deterioration of wall surface accuracy. Since stainless steel, mild steel, and the like are generally materials that easily generate burrs and are easily stretched, the present invention is particularly suitable for groove processing of such materials, and a remarkable effect has been recognized. In the case of processing a material that discharges shear-type chips and crack-type chips, setting the axial lake α to a positive value is not preferable because it may cause adverse effects. For example, stress concentrates on the cutting edge, which may cause a decrease in cutting edge strength.

The radial lake β is set at -5 ° to -30 °. The radial rake β is set to be negative in order to increase the cutting edge strength and to reduce the contact area between the rake face and the chips. This is because stainless steel, mild steel, and the like discharge flow-type chips, so that the contact area between the chips and the chip tends to be large, which may increase the cutting resistance. Therefore, attaching a carved breaker or the like to the rake face of the chip makes the radial lake β positive,
Improper. The upper limit value and the lower limit value are set in this manner in order to obtain the effects of the present invention and not to reduce the chip disposability.

Here, the tool specifications of the throw-away type side cutter according to the present invention are summarized as follows.
00 to 200 mm, blade width W = 4 to 13 mm, number of blades Z = 8
~ 20 sheets, axial rake α = 3 ° ~ 25 °, radial rake β = -5 ° ~ -30 °, outer clearance angle γ = 1 ° ~
It is set to 6 °. Here, the outer clearance angle γ refers to the angle between the long side cutting edge 14 and the inner wall surface of the groove, as shown in FIG.
The chips 7 are arranged in a staggered blade form as described above. When the blade width W is small, as shown in the present embodiment, the right blade and the left blade are each composed of one row in total, and when the blade width W is large, the right blade and the left blade are each composed of two rows. A configuration having a total of four rows may be employed. In order to improve the accuracy of the processing groove, a chamfer surface corresponding to a so-called flickering land may be formed on the short side cutting edge 15 on the outer peripheral side.

FIGS. 5 and 6 clearly show the throwaway tip 7 attached to the throwaway type side cutter. The chip 7 is a so-called positive chip in which a cemented carbide is used as its constituent material, upper and lower surfaces 8 and 9 are formed in a square shape, and a relief angle is given in advance. The outer side surfaces 10 and 11 are formed in a trapezoidal shape, and are mounted so that the upper bottom is a seating surface and the lower bottom is a side surface. A pair of outer surfaces 10 of the outer surfaces 10 and 11 form a rake surface, and the other pair of outer surfaces 11 form a flank surface. A cutting edge is provided at the side ridge of the outer surface 10 which is a rake face, and the short side cutting edge 15 is arranged in the groove width direction X and the long side cutting edge 14 is arranged in the groove depth direction Y. A corner R is formed at an acute corner 13 where the short side cutting edge 15 and the long side cutting edge 14 intersect.

Next, FIG. 7 shows a second embodiment of the present invention. The bottom plate 18 which is in contact with the chip 17 and located rearward in the rotation direction N of the tool main body 16 is fixed by a tightening screw 19 with its thickness direction directed in the axial direction of the tool main body 16. This floor plate 18 prevents deformation and damage of the tool body 16,
This is effective in preventing chip 17 from being lost. The description of the same components as those of the first embodiment is omitted.

[0023]

According to the present invention, the biting property is improved,
Burrs can be prevented from being generated due to sharp sharpness.
In addition, cutting resistance is reduced, and machining can be performed smoothly without generating chatter and vibration. Furthermore, excellent accuracy of the groove inner wall surface can be obtained without the discharged chips coming into contact with the groove inner wall surface.

[Brief description of the drawings]

FIG. 1 is a perspective view of a throw-away type side cutter showing a first embodiment of the present invention.

FIG. 2 is a front view of the throw-away type side cutter shown in FIG.

FIG. 3 is a side view of FIG. 2;

FIG. 4 is a view for explaining a state of grooving processing.

5 (a) is a plan view, FIG. 5 (b) is a front view, and FIG. 5 (c) is a side view showing a throw away tip mounted on the throw away type side cutter shown in FIG.

FIG. 6 is a perspective view of the throw-away tip shown in FIG.

7A and 7B show a second embodiment of the present invention, wherein FIG. 7A is a front view and FIG. 7B is a plan view.

FIG. 8 is a front view showing an example of a conventional throw-away type side cutter.

FIG. 9 is a plan view of the throw-away type side cutter of FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool main body 3 Chip mounting seat 6 Chip pocket 7 Chip 8 Chip upper surface 10, 11 Chip side surface 14 Long side cutting edge 15 Short side cutting edge 18 Base plate

Claims (2)

[Claims] A throw-in insert having a rectangular flat plate-like shape as a rake face is detachably mounted on a tip mounting seat recessed in an outer peripheral side surface of a disk-shaped tool body. In the away type side cutter, the throw away tip is provided with a clearance angle, the outer surface is formed in an external trapezoidal shape, and a pair of outer surfaces facing each other is an outer surface serving as a rake surface. A corner R is formed in a trapezoidal acute angle corner, and the throw away tip is mounted in a staggered blade form such that the trapezoid has an upper base serving as a seating surface and a lower base serving as a side surface. Type side cutter. 2. The cutting edge of the indexable insert,
Axial rake α = 3 ° to 25 °, radial rake β
= A throw-away type side cutter characterized by being set to -5 ° to -30 °.